Articles de revues : « Olio microbico »

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Baker, J., K. Brown, E. Rajendiran, A. Yip, D. DeCoffe, C. Dai, E. Molcan et al. « Medicinal lavender modulates the enteric microbiota to protect against Citrobacter rodentium-induced colitis ». American Journal of Physiology-Gastrointestinal and Liver Physiology 303, n^o 7 (1 octobre 2012) : G825—G836. http://dx.doi.org/10.1152/ajpgi.00327.2011.

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Inflammatory bowel disease, inclusive of Crohn's disease and ulcerative colitis, consists of immunologically mediated disorders involving the microbiota in the gastrointestinal tract. Lavender oil is a traditional medicine used to relieve many gastrointestinal disorders. The goal of this study was to examine the therapeutic effects of the essential oil obtained from a novel lavender cultivar, Lavandula × intermedia cultivar Okanagan lavender (OLEO), in a mouse model of acute colitis caused by Citrobacter rodentium . In colitic mice, oral gavage with OLEO resulted in less severe disease, including decreased morbidity and mortality, reduced intestinal tissue damage, and decreased infiltration of neutrophils and macrophages, with reduced levels of TNF-α, IFN-γ, IL-22, macrophage inflammatory protein-2α, and inducible nitric oxide synthase expression. This was associated with increased levels of regulatory T cell populations compared with untreated colitic mice. Recently, we demonstrated that the composition of the enteric microbiota affects susceptibility to C. rodentium -induced colitis. Here, we found that oral administration of OLEO induced microbiota enriched with members of the phylum Firmicutes, including segmented filamentous bacteria, which are known to protect against the damaging effects of C. rodentium . Additionally, during infection, OLEO treatment promoted the maintenance of microbiota loads, with specific increases in Firmicutes bacteria and decreases in γ-Proteobacteria. We observed that Firmicutes bacteria were intimately associated with the apical region of the intestinal epithelial cells during infection, suggesting that their protective effect was through contact with the gut wall. Finally, we show that OLEO inhibited C. rodentium growth and adherence to Caco-2 cells, primarily through the activities of 1,8-cineole and borneol. These results indicate that while OLEO promoted Firmicutes populations, it also controlled pathogen load through antimicrobial activity. Overall, our results reveal that OLEO can protect against colitis through the microbial-immunity nexus and that a pharmacological agent, in this case OLEO, alters the normal enteric microbiota.

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Engelen, Bert, Kristin Meinken, Friedrich von Wintzingerode, Holger Heuer, Hans-Peter Malkomes et Horst Backhaus. « Monitoring Impact of a Pesticide Treatment on Bacterial Soil Communities by Metabolic and Genetic Fingerprinting in Addition to Conventional Testing Procedures ». Applied and Environmental Microbiology 64, n^o 8 (1998) : 2814–21. http://dx.doi.org/10.1128/aem.64.8.2814-2821.1998.

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Herbogil (dinoterb), a reference herbicide, the mineral oil Oleo (paraffin oil used as an additive to herbicides), and Goltix (metamitron) were taken as model compounds for the study of impacts on microbial soil communities. After the treatment of soil samples, effects on metabolic sum parameters were determined by monitoring substrate-induced respiration (SIR) and dehydrogenase activity, as well as carbon and nitrogen mineralization. These conventional ecotoxicological testing procedures are used in pesticide registration. Inhibition of biomass-related activities and stimulation of nitrogen mineralization were the most significant effects caused by the application of Herbogil. Even though Goltix and Oleo were used at a higher dosage (10 times higher), the application of Goltix resulted in smaller effects and the additive Oleo was the least-active compound, with minor stimulation of test parameters at later observation times. The results served as a background for investigation of the power of “fingerprinting” methods in microbial ecology. Changes in catabolic activities induced by treatments were analyzed by using the 95 carbon sources provided by the BIOLOG system. Variations in the complex metabolic fingerprints demonstrated inhibition of many catabolic pathways after the application of Herbogil. Again, the effects of the other compounds were expressed at much lower levels and comprised stimulations as well as inhibitions. Testing for significance by a multivariate t test indicated that the sensitivity of this method was similar to the sensitivities of the conventional testing procedures. The variation of sensitive carbon sources, as determined by factor weights at different observation times, indicated the dynamics of the community shift induced by the Herbogil treatment in more detail. DNA extractions from soil resulted in a collection of molecules representing the genetic composition of total bacterial communities. Distinct and highly reproducible community patterns, or genetic fingerprints, resulting from application of the different herbicides were obtained by the sequence-specific separation of partial 16S rDNA amplification products in temperature gradient gel electrophoresis. Significant pattern variations were quantified. For detailed analysis, application-responsive bands from the Herbogil and Oleo treatments were sequenced and their tentative phylogenetic positions were identified. Data interpretation and the potentials and biases of the additional observation windows on microbial communities are discussed.

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Kostrzewska-Szlakowska, Iwona, et Bartosz Kiersztyn. « Microbial Biomass and Enzymatic Activity of the Surface Microlayer and Subsurface Water in Two Dystrophic Lakes ». Polish Journal of Microbiology 66, n^o 1 (30 mars 2017) : 75–84. http://dx.doi.org/10.5604/17331331.1234995.

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Nutrient and organic matter concentration, microbial biomass and activities were studied at the surface microlayers (SML) and subsurface waters (SSW) in two small forest lakes of different water colour. The SML in polyhumic lake is more enriched with dissolved inorganic nitrogen (0.141 mg l–1) than that of oligohumic lake (0.124 mg l–1), the former also contains higher levels of total nitrogen (2.66 mg l–1). Higher activities of lipase (Vmax 2290 nmol l–1 h–1 in oligo- and 6098 in polyhumic) and glucosidase (Vmax 41 nmol l–1 h–1 in oligo- and 49 in polyhumic) were in the SMLs in both lakes. Phosphatase activity was higher in the oligohumic SML than in SSW (Vmax 632 vs. 339 nmol l–1 h–1) while in polyhumic lake was higher in SSW (Vmax 2258 nmol l–1 h–1 vs. 1908 nmol l–1 h–1). Aminopeptidase activity in the SSW in both lakes was higher than in SMLs (Vmax 2117 in oligo- and 1213 nmol l–1 h–1 in polyhumic). It seems that solar radiation does inhibit neuston microbial community as a whole because secondary production and the share of active bacteria in total bacteria number were higher in SSW. However, in the oligohumic lake the abundance of bacteria in the SML was always higher than in the SSW (4.07 vs. 2.69 × 106 cells ml–1) while in the polyhumic lake was roughly equal (4.48 vs. 4.33 × 106 cells ml–1) in both layers. Results may also suggest that surface communities are not supplemented by immigration from bulk communities. The SML of humic lakes may act as important sinks for allochthonous nutrient resources and may then generate considerable energy pools for microbial food webs.

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Dong, Zixing, Cunduo Tang, Yunfeng Lu, Lunguang Yao et Yunchao Kan. « Microbial Oligo‐α‐1,6‐Glucosidase : Current Developments and Future Perspectives ». Starch - Stärke 72, n^o 1-2 (25 octobre 2019) : 1900172. http://dx.doi.org/10.1002/star.201900172.

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Suzuki, Natsuhei, Daito Suda, Nguyen Thi Thuy Ngan, Namiko Gibu, Nguyen Lan Huong, To Kim Anh et Daisuke Kasai. « Characterization of Latex-Clearing Protein and Aldehyde Dehydrogenases Involved in the Utilization of poly(cis-1,4-isoprene) by Nocardia farcinica NBRC 15532 ». Microorganisms 10, n^o 12 (24 novembre 2022) : 2324. http://dx.doi.org/10.3390/microorganisms10122324.

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Microbial degradation of natural rubber and synthetic poly(cis-1,4-isoprene) is expected to become an alternative treatment system for waste from poly(cis-1,4-isoprene) products including scrap tires. Nocardia farcinica NBRC 15,532, a gram-positive rubber-degrading bacterium, can utilize poly(cis-1,4-isoprene) as the sole source of carbon and energy to produce oligo-isoprene metabolites containing aldehyde and keto end groups. A homology-based search of the genome revealed a gene encoding a latex-clearing protein (Lcp). Gene disruption analysis indicated that this gene is essential for the utilization of poly(cis-1,4-isoprene) in this strain. Further analysis of the genome sequence identified aldehyde dehydrogenase (ALDH) genes as potential candidates for oxidative degradation of oligo-isoprene aldehydes. Based on the enzymatic activity of the ALDH candidates, NF2_RS14000 and NF2_RS14385 may be involved in the degradation of oligo-isoprene aldehydes. Analysis of the reaction products revealed that these ALDHs oxidized tri- to penta-isoprene aldehydes, which were generated by the reaction of Lcp. Based on the inability of ALDH gene deletion mutants, we concluded that NF2_RS14000 is mainly involved in the utilization of poly(cis-1,4-isoprene) and the oxidative degradation of oligo-isoprene aldehydes in Nocardia farcinica NBRC 15,532.

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Zhao, Liting, Zhongbao Ma, Jian Yin, Guiyang Shi et Zhongyang Ding. « Biological strategies for oligo/polysaccharide synthesis : biocatalyst and microbial cell factory ». Carbohydrate Polymers 258 (avril 2021) : 117695. http://dx.doi.org/10.1016/j.carbpol.2021.117695.

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Li, Ruming, Brian Fristensky et Guixue Wang. « Sequence data analysis and preprocessing for oligo probe design in microbial genomes ». AIMS Bioengineering 4, n^o 1 (2017) : 28–45. http://dx.doi.org/10.3934/bioeng.2017.1.28.

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Varliero, Gilda, Jared Wray, Cédric Malandain et Gary Barker. « PhyloPrimer : a taxon-specific oligonucleotide design platform ». PeerJ 9 (29 avril 2021) : e11120. http://dx.doi.org/10.7717/peerj.11120.

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Many environmental and biomedical biomonitoring and detection studies aim to explore the presence of specific organisms or gene functionalities in microbiome samples. In such cases, when the study hypotheses can be answered with the exploration of a small number of genes, a targeted PCR-approach is appropriate. However, due to the complexity of environmental microbial communities, the design of specific primers is challenging and can lead to non-specific results. We designed PhyloPrimer, the first user-friendly platform to semi-automate the design of taxon-specific oligos (i.e., PCR primers) for a gene of interest. The main strength of PhyloPrimer is the ability to retrieve and align GenBank gene sequences matching the user’s input, and to explore their relationships through an online dynamic tree. PhyloPrimer then designs oligos specific to the gene sequences selected from the tree and uses the tree non-selected sequences to look for and maximize oligo differences between targeted and non-targeted sequences, therefore increasing oligo taxon-specificity (positive/negative consensus approach). Designed oligos are then checked for the presence of secondary structure with the nearest-neighbor (NN) calculation and the presence of off-target matches with in silico PCR tests, also processing oligos with degenerate bases. Whilst the main function of PhyloPrimer is the design of taxon-specific oligos (down to the species level), the software can also be used for designing oligos to target a gene without any taxonomic specificity, for designing oligos from preselected sequences and for checking predesigned oligos. We validated the pipeline on four commercially available microbial mock communities using PhyloPrimer to design genus- and species-specific primers for the detection of Streptococcus species in the mock communities. The software performed well on these mock microbial communities and can be found at https://www.cerealsdb.uk.net/cerealgenomics/phyloprimer.

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Jenzsch, Marco, Norbert Volk, Jörg Kressler et Carmen Scholz. « Synthesis of Microbial Poly(β-hydroxybutyrate) Modified with Oligo(pentaerythritol ethoxylate) byRalstonia eutropha ». Biomacromolecules 2, n^o 3 (septembre 2001) : 1055–60. http://dx.doi.org/10.1021/bm010088o.

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Chauhan, Puneet, Saurabh Singh, Shekher Chauhan, Dileep S. Baghel et Kamal Kumar. « An Overview on “Boswellia serrata” ». Asian Pacific Journal of Health Sciences 8, n^o 4 (31 décembre 2021) : 21–24. http://dx.doi.org/10.21276/apjhs.2021.8.4s.4.

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“Boswellia serrata” is a herb used for ages in the Indian system of medicine and other systems of medicines across the world. It comes under the family “Burseraceae”. The Boswellia serrata is called by various local names in different regions, out of which “Kundur” “salai” “guggul” “Shallaki” are very prominently used. “Shallaki” is a widely used active ingredient in the “Unani” “Siddha” and “Ayurvedic” medicines oriented for the treatment of inflammation and pain. It is also used as a component to add fragrance to the products. Boswellia serrata plant contains oleo-gum resins and the ASU drug manufacturer mostly use this resin to prepare Boswellia-oriented drugs and this practice of using resin as the key component of drugs is very old and effective. In ancient ayurvedic texts, particular methods describe the extraction, purification, and usage of this oleo gum resin. Now in the modern era, when a lot of research has been done on this plant and its parts, this plant has come out to be even more important as it is found to be showing specific characteristics beneficial for treating illnesses such as dysentery, urinary tract disorders, hemorrhoids, ulcers, and dyspepsia. The present review provides an overview of some pharmacological activities and the importance of “Salaiguggal” or “ Boswellia serrata “. “Salai guggal” is rich in essential oils, and therefore, it becomes important for the perfume industries as its essential oils are soothing to smell and show therapeutic effects. The essential oils of Boswellia serrata are a mixture of different boswellic acids such as “mono-terpenes”, “di-tepenes” and “sesqui-terpenes”. Whereas the oleo gum resin of “ Boswellia serrata “ comprises monosaccharides such as pentose and hexose sugars. The oleo gum resin of this plant is highly recommended by almost every medical practitioner who deals in herbal medicines as it has shown a huge range of effective characteristics in asthma, cancer, microbial/fungal infections, inflammation, arthritis, diarrhea, and also as an analgesic. A proper systematic literature review was done using different databases that were available online like Google Scholar, PubMed, and ScienceDirect.

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Roche, Adeline, Emmanuelle Vennin, Anthony Bouton, Nicolas Olivier, Aurélia Wattinne, Irina Bundeleva, Jean-François Deconinck, Aurélien Virgone, Eric C. Gaucher et Pieter T. Visscher. « Oligo-Miocene lacustrine microbial and metazoan buildups from the Limagne Basin (French Massif Central) ». Palaeogeography, Palaeoclimatology, Palaeoecology 504 (septembre 2018) : 34–59. http://dx.doi.org/10.1016/j.palaeo.2018.05.001.

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Chaikliang, Chiraphon, Santad Wichienchot, Wirote Youravoug et Potchanapond Graidist. « Evaluation on prebiotic properties of β-glucan and oligo-β-glucan from mushrooms by human fecal microbiota in fecal batch culture ». Functional Foods in Health and Disease 5, n^o 11 (30 novembre 2015) : 395. http://dx.doi.org/10.31989/ffhd.v5i11.209.

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Background: β-glucan is dietary fiber, a structural polysaccharide, β-linked linear chains of D-glucose polymers with variable frequency of branches. β-glucan is isolated from different sources such as cell walls of baker’s yeast (Saccharomyces cerevisiae), cereals (oat and barley) and various species of mushrooms. Among 8 mushrooms in the study, Schizophylum commune Fr and Auricularia auricula Judae had the highest in β-glucan contents and the cheapest cost of mushroom per content of β-glucan, respectively. Even the function of β-glucan on immune modulation has been known however no report on interaction between β-glucan and human gut microbiota. Gut microbiota is thought to have health effects by interaction with non-digestible component particular fermentable dietary fiber. It is important to correlate the specific groups of the microbial communities associated with β-glucan fermentation and the consequential SCFA profiles. β-glucan from mushroom may has potential prebiotic function similar to those from commercial yeast (Saccharomyces cerevisiae) β-glucan. Objective: To evaluate on prebiotic properties of soluble β-glucans and oligo-β-glucans from Schizophylum commune Fr and Auricularia auricula Judae by fecal fermentation in batch culture. Methods: In vitro fecal fermentation in anaerobic batch cultures under simulated conditions similar to human colon with human faecal samples from three donors were performed. Comparison on 3 β-glucans and 2 oligo-β-glucans have been studied. Sample was taken at 0 h, 24 h and 48 h to analyze the numbers of bacterial changes by fluorescent in situ hybridization (FISH) technique. Short chain fatty acids (SCFA) were analyzed by HPLC. The prebiotic index (PI) was calculated according to the change of 5 specific bacterial genus within 48 h fermentation. Results: Soluble β-glucan from Auricularia auricula Judae increased numbers of bifidobacteria and lactobacillus significantly (P<0.05). The PI of soluble β-glucan and oligo-β-glucan from Schizophylum commune Fr were 0.01 and -0.01, respectively. β-glucan and oligo-β-glucan from Auricularia auricula Judae were 0.11 and -0.07, respectively. Whereas PI of β-glucan from commercial yeast (Saccharomyces cerevisiae) was 0.03. Acetate was the most prevalent SCFA found in all treatments followed by propionate, butyrate and lactate, respectively. Conclusion: The study confirmed that β-glucan from Schizophylum commune Fr and Auricularia auricula Judae are candidate prebiotics. Keywords: β-glucan, oligo-β-glucan, prebiotic, mushroom, fecal batch culture

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Hong, Chae Hwan, Si Hwan Kim, Ji-Yeon Seo et Do Suck Han. « Development of Four Unit Processes for Biobased PLA Manufacturing ». ISRN Polymer Science 2012 (15 mars 2012) : 1–6. http://dx.doi.org/10.5402/2012/938261.

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Polylactide (PLA), which is one of the most important biocompatible polyesters that are derived from annually renewable biomass such as corn and sugar beets, has attracted much attention for automotive parts application. The manufacturing method of PLA is the ring-opening polymerization of the dimeric cyclic ester of lactic acid, lactide. For the stereocomplex PLA, we developed the four unit processes, fermentation, separation, lactide conversion, and polymerization. Fermentation of sugars to D-lactic acid is little studied, and its microbial productivity is not well known. Therefore, we investigated D-lactic acid fermentation with a view to obtaining the strains capable of producing D-lactic acid, and we got a maximum lactic acid production 60 g/L. Lactide is prepared by a two-step process: first, the lactic acid is converted into oligo(lactic acid) by a polycondensation reaction; second, the oligo(lactic acid) is thermally depolymerized to form the cyclic lactide via an unzipping mechanism. Through catalyst screening test for polycondensation and depolymerization reactions, we got a new method which shortens the whole reaction time 50% the level of the conventional method. Poly(L-lactide) was obtained from the ring-opening polymerization of L-lactide. We investigated various catalysts and polymerization conditions. Finally, we got the best catalyst system and the scale-up technology.

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Jasser, Iwona, et Iwona Kostrzewska-Szlakowska. « Fading out of the trophic cascade at the base of the microbial food web caused by changes in the grazing community in mesocosm experiments ». Oceanological and Hydrobiological Studies 41, n^o 1 (1 janvier 2012) : 1–11. http://dx.doi.org/10.2478/s13545-012-0001-7.

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AbstractBiomanipulation of consumer populations can have strong top-down impacts on the composition and biomass of lower trophic levels. In this paper, we assess how changes in crustaceans’ biomass influence classical grazing and the microbial food web in an oligo-mesohumic, low-pH lake (Mazurian Lake District, Poland). Removal of mesozooplankton from the experimental mesocosms created a gradient of crustacean biomass resulting in the biomass increase of rotifers, phytoplankton and protozooplankton, while autotrophic eukaryotic picoplankton (eu-APP) and bacteria were not affected. The strongest modifications concerned the rotifer biomass and phytoplankton community structure. Our results imply that the trophic cascade generated in the experiment did not extend to bacteria and eu-APP.

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Rawat, Neelam, Yadevendra Yadav, Shuchi Mitra, Usha Sharma et Khem Chand Sharma. « ANTI-INFLAMMATORY AND ANTI-MICROBIAL ACTION OF TRIPHALA GUGGULU : A REVIEW ». International Journal of Research in Ayurveda and Pharmacy 13, n^o 04 (30 août 2022) : 121–30. http://dx.doi.org/10.7897/2277-4343.1304101.

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Triphala Guggulu, an Ayurvedic herbal formulation, consists of dried powder of fruits of three plants commonly known as Triphala: Emblica officinalis Gaertn. (Euphorbiaceae), Terminalia bellerica Roxb. (Combretaceae) and Terminalia chebula Retz. (Combretaceae) along with Piper longum Linn. (Piperaceae), combined with the oleo-gum resin of Commiphora wightii Arnott. Bhandari (Burseraceae). It is mentioned in the Ayurvedic Formulary of India (AFI) taken from Sharngadhar Samhita for several therapeutic uses. This formulation is indicated in the treatment of Bhagandara (fissure-in-ano), Gulma (Benign growths), Shotha (Inflammation) and Arsha (Piles) by Acharya Sharangdhara Mishra in his book. This review article aims to evaluate all the experimental work done on the anti-inflammatory and anti-microbial action of constituents of Triphala Guggulu. A review of all research work was done from the Central Council of Research in Ayurvedic Sciences (CCRAS) database of medicinal plants and online research journals. The outcome of this study shows that all Triphala Guggulu ingredients can work as anti-inflammatory and antibacterial activity against a wide range of microbes. Thus, Triphala Guggulu is an effective formulation to cure infectious wounds and normalize gut motility, beneficial in health conditions such as Piles, Fistula, Inflammation etc.

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Yanez-Montalvo, Alfredo, Bernardo Aguila, Elizabeth Selene Gómez-Acata, Miriam Guerrero-Jacinto, Luis A. Oseguera, Luisa I. Falcón et Javier Alcocer. « Shifts in water column microbial composition associated to lakes with different trophic conditions : “Lagunas de Montebello” National Park, Chiapas, México ». PeerJ 10 (16 septembre 2022) : e13999. http://dx.doi.org/10.7717/peerj.13999.

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Eutrophication is a global problem causing the reduction of water quality and the loss of ecosystem goods and services. The lakes of the “Lagunas de Montebello” National Park (LMNP), Chiapas, Mexico, not only represent unique and beautiful natural scenic sites in southern Mexico but are also a national protected area and RAMSAR site. Unfortunately, some of these lakes started showing eutrophication signs since 2003. Anthropogenic activities (e.g., land-use change from forested to agricultural and urban development) are leading to water quality and trophic state alterations of the lakes of the LMNP. This study shows the results of a coupled limnological characterization and high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene to analyze the microbial composition of the water column in a set of oligotrophic and eutrophic lakes. Chlorophyll a (Chl-a) was the main environmental parameter correlated with the trophic conditions of the lakes. Although the microbial diversity was similar, the microbial composition changed significantly from oligo to eutrophic lakes. Proteobacteria, Firmicutes, and Cyanobacteria were the main components of oligotrophic lakes, and Cyanobacteria, Proteobacteria, and Bacteroidetes of eutrophic lakes. While Acinetobacter (Proteobacteria) and Cyanobium (a unicellular cyanobacterium) dominated in oligotrophic lakes, the filamentous, bloom-forming, and toxin-producing cyanobacteria Planktothrix was the dominant genus in eutrophic lakes. High-throughput sequencing allowed the detection of changes in the composition of the microbial component in oligotrophic lakes, suggesting a shift towards eutrophication, highlighting the relevance of sensitive monitoring protocols of these ecosystems to implement remediation programs for eutrophicated lakes and conservation strategies for those yet pristine.

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Kaya, İsmet, et Nilüfer Cihangiroğlu. « Synthesis, Characterization and Anti-microbial Activity of Oligo-N-2-aminopyridinylsalicylaldimine and Some Oligomer-metal Complexes ». Journal of Polymer Research 11, n^o 1 (mars 2004) : 37–42. http://dx.doi.org/10.1023/b:jpol.0000021746.50347.34.

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Teper, Paulina, Anna Sotirova, Agnieszka Kowalczuk, Barbara Mendrek et Tsvetelina Paunova-Krasteva. « Effects of cationic polymers on the viability of microbial biofilms ». Folia Medica 65, n^o 1 (28 février 2023) : 124–30. http://dx.doi.org/10.3897/folmed.65.e76154.

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Introduction: The number of published biofilm studies and novel ways for studying them has risen dramatically in recent years, ow-ing to the broad application of biofilms in medicine. Some bacteria develop biofilms that are highly resistant to antimicrobial agents, resulting in persistent infections. This necessitates the development of alternative methods for combating biofilms. In this regard, the application of cationic polymers is a good candidate for realization of this strategy.  Aim: The aim of our study was to investigate the potential of a newly synthesized covalently attached star copolymer of N,N’-dimeth-ylaminoethyl methacrylate and hydroxyl-bearing oligo(ethylene glycol) methacrylate [P(DMAEMA-co-HOEGMA)] to silica surfaces and its quaternized version [P(QDMAEMA-co-HOEGMA)] for destruction of biofilms formed by Bacillus subtilis or Pseudomonas aeruginosa.  Materials and methods: Model strains representing different genera and taxonomic groups were selected for the study. The anti-biofilm activities of two different newly synthesized cationic polymers were investigated by observation (live/dead staining) of the viability of bacterial cells within the biofilm. Results: The results obtained by the live/dead labeling of bacterial biofilms show a substantial decrease in the viability of population in the presence of cationic polymers, better expressed at B. subtilis. Conclusions: The studied two immobilized on silica wafers newly synthesized star copolymers exhibited potential for anti-biofilm effects. The results demonstrated combined potential for reducing the viability of bacterial cells within the biofilms and probably for loosening the biofilm matrix. The effect was better expressed in B. subtilis.

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Knittel, Diana N., Ursula Huber, Florian C. Stintzing et Dietmar R. Kammerer. « Effect of extraction, microbial fermentation and storage on the cardenolide profile of Strophanthus kombé Oliv. seed preparations ». Journal of Pharmaceutical and Biomedical Analysis 129 (septembre 2016) : 96–104. http://dx.doi.org/10.1016/j.jpba.2016.06.036.

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Kaya, Ismet, Adalet R. Vilayeto?lu et Hasan Topak. « Synthesis of oligo-ortho-azomethinephenol and its oligomer-metal complexes : Characterization and application as anti-microbial agents ». Journal of Applied Polymer Science 85, n^o 9 (12 juin 2002) : 2004–13. http://dx.doi.org/10.1002/app.10815.

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Salama, Hatem Ali, Ahmed Noah Badr, Manal F. Elkhadragy, Ahmed Mohamed Said Hussein, Ibrahim Abdel-Salam Shaban et Hany M. Yehia. « New Antifungal Microbial Pigment Applied to Improve Safety and Quality of Processed Meat-Products ». Microorganisms 9, n^o 5 (4 mai 2021) : 989. http://dx.doi.org/10.3390/microorganisms9050989.

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Minced meat is involved within numerous products, where their color attributes are affected by consumer preferences. This study was aimed to ameliorate processed meat color, using a microbial red pigment. Antibacterial, antifungal, citrinin-free, and toxicity of pigment were determined. Meatballs and burgers were manufactured using pigment at 3 mg/g of meat. Texture, color, shelf life extension, and organoleptic properties were estimated for treated meats. Results were expressed by a real antimicrobial for pigment, even via several extracting systems. The MIC and MFC of pigment were 320 µg/g and 2.75 mg/g media, respectively. Bioactive components of pigment were detected using the GC–MS and the FTIR apparatus. The bioactive carbohydrates include oligo and polysaccharides were manifested with real curves. Secretion of ochratoxin A and aflatoxins in fungal media receives pigment was decreased by up to 54% and 45%, respectively. The presence of bioactive carbohydrates may trap mycotoxin out of the recovered amounts. The manufactured products were enhanced for their color and taste with fine texture changes. The shelf life of colored-frying meat was recorded by an extension compared to the control. In conclusion, the results were recommended microbial red-pigment implementation in meats manufacturing for ameliorating recorded of color, as antimycotoxigenic, and shelf life extension.

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Bello Alvarez, Oscar Fernando, José Francisco García Molano et William Javier Cuervo Bejarano. « Cuantificación de diazótrofos en la rizósfera del olivo (Olea europaea L.) cultivado en Boyacá, Colombia ». Acta Agronómica 65, n^o 2 (29 décembre 2015) : 109–15. http://dx.doi.org/10.15446/acag.v65n2.44270.

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La investigación desarrollada tuvo como objeto cuantificar y determinar la actividad de las unidades formadoras de colonias de microorganismos fijadores de nitrógeno asociados a la rizósfera de árboles de olivo, plantados en el municipio de Sutamarchán, finca las Acacias de la provincia del Alto Ricaurte. Se utilizó un diseño en bloques con submuestras, teniendo como tratamientos la poda y el crecimiento libre; se usaron seis unidades experimentales (árboles) tres por tratamiento, los árboles eran jóvenes (<4 años) e iniciaban producción. Se tomaron muestras foliares y edáficas, se evaluaron los niveles poblacionales de microorganismos diazótrofos, se midió a nivel foliar el N% contenido y a nivel del suelo las concentraciones de NH4, NO3, CO y de fosforo, hierro y magnesio, intervinientes directamente en la fijación. En el análisis estadístico se usaron pruebas de supuestos, análisis de varianza y análisis de componentes principales. Se obtuvo que la poda generaba acidez y disminución del pH del suelo en forma significativa, los niveles foliares y edáficos de nitrógeno son bajos, pero, que las poblaciones de microorganismos fijadores son altas con poca eficiencia, al parecer por fijar en vida libre. Las concentraciones de Fe y Mg permiten inducir que la actividad de nitrogenasa es constante, pero el nitrógeno se inmoviliza posiblemente en el metabolismo microbiano, negando la posibilidad de ser absorbido por el olivo de forma directa; los niveles de calcio limitan la nutrición nitrogenada, finalmente es conveniente hacer identificación de las poblaciones, medir la actividad reductora de acetileno y la tasa de mineralización.

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Egamberdiyeva, Dilfuza, Muhiddin Mamiev et Svetlana K. Poberejskaya. « The Influence of Mineral Fertilizer Combined With a Nitrification Inhibitor on Microbial Populations and Activities in Calcareous Uzbekistanian Soil Under Cotton Cultivation ». Scientific World JOURNAL 1 (2001) : 108–13. http://dx.doi.org/10.1100/tsw.2001.301.

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Application of fertilizers combined with nitrification inhibitors affects soil microbial biomass and activity. The objective of this research was to determine the effects of fertilizer application combined with the nitrification inhibitor potassium oxalate (PO) on soil microbial population and activities in nitrogen-poor soil under cotton cultivation in Uzbekistan. Fertilizer treatments were N as urea, P as ammophos, and K as potassium chloride. The nitrification inhibitor PO was added to urea and ammophos at the rate of 2%. Three treatments—N200P140K60(T1), N200P140 POK60(T2), and N200P140 POK60(T3) mg kg-1soil—were applied for this study. The control (C) was without fertilizer and PO. The populations of oligotrophic bacteria, ammonifying bacteria, nitrifying bacteria, denitrifying bacteria, mineral assimilating bacteria, oligonitrophilic bacteria, and bacteria group Azotobacter were determined by the most probable number method. The treatments T2 and T3 increased the number of oligonitrophilic bacteria and utilization mineral forms of nitrogen on the background of reducing number of ammonifying bacteria. T2 and T3 also decreased the number of nitrifying bacteria, denitrifying bacteria, and net nitrification. In conclusion, our experiments showed that PO combined with mineral fertilizer is one of the most promising compounds for inhibiting nitrification rate, which was reflected in the increased availability and efficiency of fertilizer nitrogen to the cotton plants. PO combined with mineral fertilizer has no negative effects on nitrogen-fixing bacteria Azotobacter and oligo-nitrophilic bacteria.

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Mateescu, Carmen, Andreea Daniela Dima et Oana Cristina Pârvulescu. « Improving the biogas performance of selected waste materials by substrate ratio optimization and microalgae addition ». Journal of Engineering Sciences and Innovation 4, n^o 3 (3 septembre 2019) : 263–72. http://dx.doi.org/10.56958/jesi.2019.4.3.263.

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"Biogas production has become a common practice for obtaining renewable energy, being implemented or expanded in many countries due to a large number of advantages. The organic material conversion to biogas may be improved and optimized by co-digestion that ensures a better supply of nutrients and oligo-minerals for the microbial population. Comparative assays were conducted on the co-digestion of selected waste under different mixing ratio to identify the optimal feedstock composition for a better biomethane production. Also, experiments investigated the influence of 5% microalgal biomass addition to the selected organic mixtures on biogas production and showed that the microalgal biomass slightly increased the biogas quantity and quality without causing any delay on the mass biodegradability. The anaerobic digestion of microalgae-additivated substrates may be used as optimization method to increase the economic profitability of the biogas plants. Further research is required to establish at which extent different percentages of microalgae may induce changes in the substrates biomethane potential. "

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Roch, Toralf, Konstanze K. Julich-Gruner, Axel T. Neffe, Nan Ma et Andreas Lendlein. « Immuno-compatibility of desaminotyrosine and desaminotyrosyl tyrosine functionalized star-shaped oligo(ethylene glycol)s with different molecular weights ». MRS Proceedings 1718 (2015) : 97–102. http://dx.doi.org/10.1557/opl.2015.327.

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ABSTRACTPolymer-based therapeutic strategies require biomaterials with properties and functions tailored to the demands of specific applications leading to an increasing number of newly designed polymers. For the evaluation of those new materials, comprehensive biocompatibility studies including cyto-, tissue-, and immunocompatibility are essential. Recently, it could be demonstrated that star-shaped amino oligo(ethylene glycol)s (sOEG) with a number average molecular weight of 5 kDa and functionalized with the phenol-derived moieties desaminotyrosine (DAT) or desaminotyrosyl tyrosine (DATT) behave in aqueous solution like surfactants without inducing a substantial cytotoxicity, which may qualify them as solubilizer for hydrophobic drugs in aqueous solution. However, for biomedical applications the polymer solutions need to be free of immunogenic contaminations, which could result from inadequate laboratory environment or contaminated starting material. Furthermore, the materials should not induce uncontrolled or undesired immunological effects arising from material intrinsic properties. Therefore, a comprehensive immunological evaluation as perquisite for application of each biomaterial batch is required. This study investigated the immunological properties of sOEG-DAT(T) solutions, which were prepared using sOEG with number average molecular weights of 5 kDa, 10 kDa, and 20 kDa allowing analyzing the influence of the sOEG chain lengths on innate immune mechanisms. A macrophage-based assay was used to first demonstrate that all DAT(T)-sOEG solutions are free of endotoxins and other microbial contaminations such as fungal products. In the next step, the capacity of the different DAT(T)-functionalized sOEG solutions to induce cytokine secretion and generation of reactive oxygen species (ROS) was investigated using whole human blood. It was observed that low levels of the pro-inflammatory cytokines interleukin(IL)-1β and IL-6 were detected for all sOEG solutions but only when used at concentrations above 250 µg·mL-1. Furthermore, only the 20 kDa sOEG-DAT induced low amounts of ROS-producing monocytes. Conclusively, the data indicate that the materials were not contaminated with microbial products and do not induce substantial immunological adverse effectsin vitro,which is a prerequisite for future biological applications.

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Yan, Jing, Lei Wang, Yu Gu, Huiqin Hou, Tianyu Liu, Yiyun Ding et Hailong Cao. « Dietary Patterns and Gut Microbiota Changes in Inflammatory Bowel Disease : Current Insights and Future Challenges ». Nutrients 14, n^o 19 (27 septembre 2022) : 4003. http://dx.doi.org/10.3390/nu14194003.

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Inflammatory bowel disease (IBD) is a result of a complex interplay between genes, host immune response, gut microbiota, and environmental factors. As one of the crucial environmental factors, diet plays a pivotal role in the modulation of gut microbiota community and the development of IBD. In this review, we present an overview of dietary patterns involved in the pathogenesis and management of IBD, and analyzed the associated gut microbial alterations. A Westernized diet rich in protein, fats and refined carbohydrates tends to cause dysbiosis and promote IBD progression. Some dietary patterns have been found effective in obtaining IBD clinical remission, including Crohn’s Disease Exclusion Diet (CDED), Mediterranean diet (MD), Anti-Inflammatory Diet (AID), the low-“Fermentable Oligo-, Di-, Mono-saccharides and Polyols” (FODMAP) diet, Specific Carbohydrate Diet (SCD), and plant-based diet, etc. Overall, many researchers have reported the role of diet in regulating gut microbiota and the IBD disease course. However, more prospective studies are required to achieve consistent and solid conclusions in the future. This review provides some recommendations for studies exploring novel and potential dietary strategies that prevent IBD.

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Jugnia, Louis B., Rémy D. Tadonléké, T. Sime-Ngando, J. Devaux et C. Andrivon. « Bacterial population dynamics, production, and heterotrophic activity in a recently formed reservoir ». Canadian Journal of Microbiology 45, n^o 9 (1 septembre 1999) : 747–53. http://dx.doi.org/10.1139/w99-058.

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Seasonal and spatial fluctuations in abundance, biomass production, and potential heterotrophic activity (i.e., 14C-glucose uptake) of bacterioplankton assemblages in a 1-year-old reservoir (the Sep Reservoir, Puy-de-Dôme, France) were examined concurrently with water temperature, phytoplankton chlorophyll a concentration, and primary production (PP). Based on the values observed for these biological variables, the Sep Reservoir was considered to have evolved to an oligo-mesotrophic state. Spatiotemporal variations of bacterial variables were a consequence of the seasonal evolution of the reservoir coupled with the resource availability. Multivariate regression analyses suggest that about 14 and 26% of the variance in bacterial standing stock and activity may be explained by the physical environment (i.e., temperature) and a resource availability index (chlorophyll a concentration or primary production), respectively. A carbon budget indicated that 4-126% (mean = 20%) of the ambient PP may be channeled through the microbial loop via bacterial biomass production. Heterotrophic bacterial production in the Sep Reservoir may therefore, on occasion, represent a significant source of carbon for higher order consumers.Key words: reservoirs, plankton, bacteria, heterotrophic uptake, primary and bacterial production.

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Boychenko, T. V., N. K. Khristoforova et A. A. Emelyanov. « MICROBIAL INDICATION OF POLLUTION FOR THE SURFACE WATERS IN THE NOVIK BAY (RUSSKY ISLAND, PETER THE GREAT BAY, JAPAN SEA) ». Izvestiya TINRO 198 (2 octobre 2019) : 186–94. http://dx.doi.org/10.26428/1606-9919-2019-198-186-194.

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The Novik Bay is the largest one among the inlets of Russky Island in Peter the Great Bay. This water area is actively used for aquaculture and commercial and recreational fishery and attracts many tourists, so permanent monitoring of its water quality is necessary. Current environmental situation in the Novik Bay is assessed using microbiological indicators. The following parameters are used: total number of heterotropic bacteria, number of coliform bacteria, and number of metal-resistant microorganisms as indicators of oil and phenolic pollution. The water samples were collected in spring and autumn of 2017 and in spring and summer of 2018, following the standards GOST 31862 and GOST 31861. The number of microorganisms was determined by standard microbiological methods of sowing. The total number of heterotrophic bacteria corresponds to the requirements for oligo- or mesosaprobic waters. The number of metal-resistant microorganisms indicates that the waters of the bay are not subjected to industrial effluents and other man-made effects, its pollution by oil products is noticeable in some local areas only but the major part of the bay is low-polluted. In comparison with the data of previous chemical-ecological and microbiological tests, these assessments show better condition of the Novik Bay waters.

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Reddel, Sofia, Lorenza Putignani et Federica Del Chierico. « The Impact of Low-FODMAPs, Gluten-Free, and Ketogenic Diets on Gut Microbiota Modulation in Pathological Conditions ». Nutrients 11, n^o 2 (12 février 2019) : 373. http://dx.doi.org/10.3390/nu11020373.

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The gut microbiota performs several essential protective, structural, and metabolic functions for host health. The maintenance of a beneficial microbiota requires a homeostatic equilibrium within microbial communities, and between the microorganisms and the host. The gut microbiota composition may be affected by external factors, among them diet habits may be considered most important. In some pathological conditions such as irritable bowel syndrome (IBS), celiac disease (CD), or neurological disorders (ND), specific dietary regimens as low-fermentable, oligo-, di-, mono-saccharides and polyols (FODMAPs), ketogenic (KD), and gluten-free (GFD) diets are considered therapeutic. These kinds of diets are characterized by a reduction or exclusion of a specific nutrient from the entire dietary pattern. Despite these alimentary regimens showing beneficial effects on disease symptoms, they can affect microbiota composition, especially if they are protracted for a long time. To date, only a few studies have reported the effects of these diets on gut microbiota. In this review, we discuss the effects of low-FODMAPs, KD, and GFD on gut microbiota modulation in pathological conditions, advancing the possibility of depicting a balanced diet and developing personalized dietary intervention protocols.

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Nikou, Theodora, Maria Eleni Sakavitsi, Evangelos Kalampokis et Maria Halabalaki. « Metabolism and Bioavailability of Olive Bioactive Constituents Based on In Vitro, In Vivo and Human Studies ». Nutrients 14, n^o 18 (13 septembre 2022) : 3773. http://dx.doi.org/10.3390/nu14183773.

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Consumption of olive products has been established as a health-promoting dietary pattern due to their high content in compounds with eminent pharmacological properties and well-described bioactivities. However, their metabolism has not yet been fully described. The present critical review aimed to gather all scientific data of the past two decades regarding the absorption and metabolism of the foremost olive compounds, specifically of the phenylalcohols hydroxytyrosol (HTyr) and tyrosol (Tyr) and the secoiridoids oleacein (Olea), oleocanthal (Oleo) and oleuropein (Oleu). A meticulous record of the in vitro assays and in vivo (animals and humans) studies of the characteristic olive compounds was cited, and a critical discussion on their bioavailability and metabolism was performed taking into account data from their gut microbial metabolism. The existing critical review summarizes the existing knowledge regarding the bioavailability and metabolism of olive-characteristic phenylalchohols and secoiridoids and spotlights the lack of data for specific chemical groups and compounds. Critical observations and conclusions were derived from correlating structure with bioavailability data, while results from in vitro, animal and human studies were compared and discussed, giving significant insight to the future design of research approaches for the total bioavailability and metabolism exploration thereof.

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Vestrum, Ragnhild Inderberg, Torunn Forberg, Birgit Luef, Ingrid Bakke, Per Winge, Yngvar Olsen et Olav Vadstein. « Commensal and Opportunistic Bacteria Present in the Microbiota in Atlantic Cod (Gadus morhua) Larvae Differentially Alter the Hosts’ Innate Immune Responses ». Microorganisms 10, n^o 1 (24 décembre 2021) : 24. http://dx.doi.org/10.3390/microorganisms10010024.

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The roles of host-associated bacteria have gained attention lately, and we now recognise that the microbiota is essential in processes such as digestion, development of the immune system and gut function. In this study, Atlantic cod larvae were reared under germ-free, gnotobiotic and conventional conditions. Water and fish microbiota were characterised by 16S rRNA gene analyses. The cod larvae’s transcriptional responses to the different microbial conditions were analysed by a custom Agilent 44 k oligo microarray. Gut development was assessed by transmission electron microscopy (TEM). Water and fish microbiota differed significantly in the conventional treatment and were dominated by different fast-growing bacteria. Our study indicates that components of the innate immune system of cod larvae are downregulated by the presence of non-pathogenic bacteria, and thus may be turned on by default in the early larval stages. We see indications of decreased nutrient uptake in the absence of bacteria. The bacteria also influence the gut morphology, reflected in shorter microvilli with higher density in the conventional larvae than in the germ-free larvae. The fact that the microbiota alters innate immune responses and gut morphology demonstrates its important role in marine larval development.

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Adamberg, K., K. Kolk, M. Jaagura, R. Vilu et S. Adamberg. « The composition and metabolism of faecal microbiota is specifically modulated by different dietary polysaccharides and mucin : an isothermal microcalorimetry study ». Beneficial Microbes 9, n^o 1 (29 janvier 2018) : 21–34. http://dx.doi.org/10.3920/bm2016.0198.

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The metabolic activity of colon microbiota is specifically affected by fibres with various monomer compositions, degree of polymerisation and branching. The supply of a variety of dietary fibres assures the diversity of gut microbial communities considered important for the well-being of the host. The aim of this study was to compare the impact of different oligo- and polysaccharides (galacto- and fructooligosaccharides, resistant starch, levan, inulin, arabinogalactan, xylan, pectin and chitin), and a glycoprotein mucin on the growth and metabolism of faecal microbiota in vitro by using isothermal microcalorimetry (IMC). Faecal samples from healthy donors were incubated in a phosphate-buffered defined medium with or without supplementation of a single substrate. The generation of heat was followed on-line, microbiota composition (V3-V4 region of the 16S rRNA using Illumina MiSeq v2) and concentrations of metabolites (HPLC) were determined at the end of growth. The multiauxic power-time curves obtained were substrate-specific. More than 70% of all substrates except chitin were fermented by faecal microbiota with total heat generation of up to 8 J/ml. The final metabolite patterns were in accordance with the microbiota changes. For arabinogalactan, xylan and levan, the fibre-affected distribution of bacterial taxa showed clear similarities (e.g. increase of Bacteroides ovatus and decrease of Bifidobacterium adolescentis). The formation of propionic acid, an important colon metabolite, was enhanced by arabinogalactan, xylan and mucin but not by galacto- and fructooligosaccharides or inulin. Mucin fermentation resulted in acetate, propionate and butyrate production in ratios previously observed for faecal samples, indicating that mucins may serve as major substrates for colon microbial population. IMC combined with analytical methods was shown to be an effective method for screening the impact of specific dietary fibres on functional changes in faecal microbiota.

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Przygrodzka, Katarzyna, Magdalena Charęza, Agnieszka Banaszek, Beata Zielińska, Ewa Ekiert et Radosław Drozd. « Bacterial Cellulose Production by Komagateibacter xylinus with the Use of Enzyme-Degraded Oligo- and Polysaccharides as the Substrates ». Applied Sciences 12, n^o 24 (10 décembre 2022) : 12673. http://dx.doi.org/10.3390/app122412673.

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Bacterial cellulose (BC) is a unique biopolymer synthesised by many bacteria as a critical element of their biofilm matrix. The most known and efficient producers of BC are bacteria from the genus of Komagataeibacter. Bacterial cellulose, with its unique properties, high crystallinity, mechanical strength, and unprecedented ability to hold water, is an object of interest in many industries. Despite the enormous efforts that have been made to develop an effective process, the economic aspect of BC production is still a limiting factor for broadening applications, and new “breaking point” solutions are highly anticipated. In this study, the possibility of using sucrose, lactose, and starch as alternative carbon sources converted to simple sugars directly in the culture medium by microbial glycohydrolases, β-D-fructofuranosidase, β-galactosidase, and glucoamylase in the process of BC synthesis was analysed. The results showed the high potential of the enzyme-assisted fermentation process that, for most used raw carbons sources, was highly efficient, with a yield higher (i.e., lactose 40% more) or comparable to the cultures maintained on standard Hestrin-Schramm media with glucose as a sole carbon source. The X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscope analyses did not reveal any negative influence of enzyme-assisted cultivation on the BC material properties, such as crystallinity, swelling ratio, and moisture content. Applying specific enzymes for converting inaccessible, raw-form carbon sources to the culture medium of Komagateibacter xylinus opens a simple way to use various oligo- and polysaccharides acquired from many kinds of biomass sources in the BC production process.

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Tiwari, Sarika Sharma, Shailesh K. Gupta, Sumeet Dwivedi et Raghvendra Dubey. « Formulation and evaluation of in situ herbal gel containing aqueous and methanolic extract of fruits of Quercus infectoria Oliv. for vaginal application ». Journal of Drug Delivery and Therapeutics 8, n^o 5 (14 septembre 2018) : 495–503. http://dx.doi.org/10.22270/jddt.v8i5.1913.

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Conventional vaginal dosage forms frequently produce leakages and drip. There is a need for the development of innovative vaginal formulation technology that fulfills certain criteria such as desirable product dispersion throughout the vagina, retention for intended intervals, and adequate release of drug. These features can be achieved by the use of bioadhesive based novel delivery systems. In-situ gelation is a process of gel formation at the site of application after the composition or formulation has been applied the site. Formulation and evaluation of one such bioadhesive based novel drug delivery system for an effective and patient friendly use of an antifungal drug to formulated In-situ gel. Quercus infectoria is medicinally important plant grown wildly in India and is useful in the treatment of fungal and microbial infection by tribal’s of India. The plant is used by tribal women to treat vaginal infection as mentioned in folk-lore. Therefore, the present plant as selected to formulate in-situ herbal gel using Quercus infectoria as active ingredients for the treatment of vaginal infection. Keywords: Herbal Gels, Quercus infectoria, bioadhesive, vaginal drug delivery

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Wang, Zhihong, Mijun Peng, Zhigang She, Minglong Zhang et Qiuling Yang. « Development of a flavor fingerprint by gas chromatography ion mobility spectrometry with principal component analysis for volatile compounds from Eucommia ulmoides Oliv. leaves and its fermentation products ». BioResources 15, n^o 4 (16 octobre 2020) : 9180–96. http://dx.doi.org/10.15376/biores.15.4.9180-9196.

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Data obtained with gas chromatography coupled with ion mobility spectrometry (GC-IMS) was explored to investigate the characteristics of volatile compounds from edible fungus, from Eucommia ulmoides Oliv. leaves (EUl) that served as growth medium, and from their fermentation products. A total of 162 signal peaks were found, of which 68 compounds were identified, including alcohols, aldehydes, ketones, acids, and esters. There were differences in the volatile constituents of the edible fungi. EUl also contained special volatile components. The volatile components in the fermentation product were different compared to the raw material, and the difference in composition and content of the characteristic compounds was also obvious. The best classification performance was obtained by principal component analysis (PCA) based on the signal intensity of the characteristic volatile compounds. The results clearly showed that the samples (edible fungi, EUl and fermentation products) in a relatively independent space would be well distinguished. This further illustrated that the composition and content of volatile components of EUl could be changed by different microbial strains through biofermentation technology. Combining the signal intensity of the flavor substance, the difference was also clearly observed. This result suggested that the flavor compounds fingerprint could be established by GC-IMS and PCA.

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Andresen, Louise C., Anna-Karin Björsne, Samuel Bodé, Leif Klemedtsson, Pascal Boeckx et Tobias Rütting. « Simultaneous quantification of depolymerization and mineralization rates by a novel <sup>15</sup>N tracing model ». SOIL 2, n^o 3 (6 septembre 2016) : 433–42. http://dx.doi.org/10.5194/soil-2-433-2016.

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Abstract. The depolymerization of soil organic matter, such as proteins and (oligo-)peptides, into monomers (e.g. amino acids) is currently considered to be the rate-limiting step for nitrogen (N) availability in terrestrial ecosystems. The mineralization of free amino acids (FAAs), liberated by the depolymerization of peptides, is an important fraction of the total mineralization of organic N. Hence, the accurate assessment of peptide depolymerization and FAA mineralization rates is important in order to gain a better process-based understanding of the soil N cycle. In this paper, we present an extended numerical 15N tracing model Ntrace, which incorporates the FAA pool and related N processes in order to provide a more robust and simultaneous quantification of depolymerization and gross mineralization rates of FAAs and soil organic N. We discuss analytical and numerical approaches for two forest soils, suggest improvements of the experimental work for future studies, and conclude that (i) when about half of all depolymerized peptide N is directly mineralized, FAA mineralization can be as important a rate-limiting step for total gross N mineralization as peptide depolymerization rate; (ii) gross FAA mineralization and FAA immobilization rates can be used to develop FAA use efficiency (NUEFAA), which can reveal microbial N or carbon (C) limitation.

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Rinninella, Emanuele, Marco Cintoni, Pauline Raoul, Antonio Gasbarrini et Maria Cristina Mele. « Food Additives, Gut Microbiota, and Irritable Bowel Syndrome : A Hidden Track ». International Journal of Environmental Research and Public Health 17, n^o 23 (27 novembre 2020) : 8816. http://dx.doi.org/10.3390/ijerph17238816.

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The interactions between diet, gut microbiota, and irritable bowel syndrome (IBS) have many complex mechanisms that are not fully understood. Food additives are one component of the modern human diet that deserves attention from science and government policies. This review aims at identifying the current knowledge about the impact of food additives on gut microbiota and their potential role in the development of IBS. To date, few data on the effect of food additives on gut microbiota in IBS patients are available. However, exposure to food additives could induce the dysbiosis and dysregulation of gut homeostasis with an alteration of the gut barrier and activation of the immune response. These microbial changes could exacerbate the gut symptoms associated with IBS, such as visceral pain, low-grade inflammation, and changes in bowel habits. Some additives (polyols) are excluded in the low fermentable oligo-, di- and monosaccharide, and polyol (FODMAP), diets for IBS patients. Even if most studies have been performed in animals, and human studies are required, many artificial sweeteners, emulsifiers, and food colorants could represent a potential hidden driver of IBS, through gut microbiota alterations. Consequently, food additives should be preventively avoided in the diet as well as dietary supplements for patients with IBS.

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Nafisi, Majse, Maria Stranne, Lisha Zhang, Jan A. L. van Kan et Yumiko Sakuragi. « The Endo-Arabinanase BcAra1 Is a Novel Host-Specific Virulence Factor of the Necrotic Fungal Phytopathogen Botrytis cinerea ». Molecular Plant-Microbe Interactions® 27, n^o 8 (août 2014) : 781–92. http://dx.doi.org/10.1094/mpmi-02-14-0036-r.

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The plant cell wall is one of the first physical interfaces encountered by plant pathogens and consists of polysaccharides, of which arabinan is an important constituent. During infection, the necrotrophic plant pathogen Botrytis cinerea secretes a cocktail of plant cell-wall-degrading enzymes, including endo-arabinanase activity, which carries out the breakdown of arabinan. The roles of arabinan and endo-arabinanases during microbial infection were thus far elusive. In this study, the gene Bcara1 encoding for a novel α-1,5-L-endo-arabinanase was identified and the heterologously expressed BcAra1 protein was shown to hydrolyze linear arabinan with high efficiency whereas little or no activity was observed against the other oligo- and polysaccharides tested. The Bcara1 knockout mutants displayed reduced arabinanase activity in vitro and severe retardation in secondary lesion formation during infection of Arabidopsis leaves. These results indicate that BcAra1 is a novel endo-arabinanase and plays an important role during the infection of Arabidopsis. Interestingly, the level of Bcara1 transcript was considerably lower during the infection of Nicotiana benthamiana compared with Arabidopsis and, consequently, the ΔBcara1 mutants showed the wild-type level of virulence on N. benthamiana leaves. These results support the conclusion that the expression of Bcara1 is host dependent and is a key determinant of the disease outcome.

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Araujo, Kallianna Dantas, Mayara Andrade Souza, Geovânia Ricardo dos Santos, Albericio Pereira de Andrade et José Vicente Ferreira Neto. « Atividade Microbiana no Solo em Diferentes Ambientes da Região Semiárida de Alagoas Microbial Activity in the Soil of Different Environments of the Semiarid Region of Alagoas ». GEOGRAFIA (Londrina) 25, n^o 2 (1 décembre 2016) : 5. http://dx.doi.org/10.5433/2447-1747.2016v25n2p5.

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O objetivo foi avaliar a atividade microbiana em diferentes ambientes (Caatinga nativa, Área com presença de Murici, Área cultivada com Palma forrageira e Área desmatada) utilizando o método da respirometria no campo, na região Semiárida de Olho D’Água do Casado-AL. O trabalho foi realizado em junho de 2012 e em cada área foram selecionados nove pontos de coleta para determinação da atividade microbiana, totalizando 72 amostras, sendo 36 no período diurno (05:00 às17: 00 h) e 36 no noturno (17:00 às 05:00h). O CO2 liberado por uma área de solo foi absorvido pela solução de KOH 0,5 N e titulado com HCl 0,1 N. Foram utilizados os indicadores fenolftaleína e alaranjado de metila a 1%, sendo usado um frasco controle que permaneceu fechado e foi submetido ao processo de titulação. Também foram retiradas amostras de solo na profundidade de 0-10 cm nos diferentes ambientes para determinação do conteúdo de água do solo e realizadas medidas de temperatura do solo na mesma profundidade. A produção de CO2 noturna foi maior do que a diurna, nos quatro agrossistemas estudados; Os diferentes sistemas de manejos influenciam a atividade metabólica dos microrganismos presentes no solo, obedecendo à seguinte sequência: Cultivada > Desmatada > Murici > Caatinga; Dentre as áreas analisadas, a que apresentou menores emissões de CO2 foi à área de Caatinga nativa que funcionou como um receptor de CO2 em contraposição a área cultivada que funcionou como emissor de CO2.The objective was to evaluate the microbial activity in different environments (native Caatinga, area with presence of Murici, cultivated with forage palm area, and deforested area) using the method of respirometry in the field, in the Semiarid region of Olho D’Água do Casado-AL. The research was performed in June 2012 and in each area nine sites were selected for determination of microbial activity, totaling 72 samples, including 36 during the day (05:00 to 17: 00 h) and 36 at night (17:00 to 05:00). The CO2 released by an area of soil was absorbed by KOH solution and titrated with 0.5 N HCl 0.1 N. There were used, the phenolphthalein and methyl orange indicators 1%, using a control flask which remained closed and submitted to the titling process. Soil samples were also collected at a depth of 0-10 cm in different environments to determine the water content of the soil and we measured the temperature of the soil at the same depth. The night CO2 production was higher than the daytime in the four environmental systems; Different managements systems influence the metabolic activity of microorganisms in the soil, in the following sequence: Cultivated > Deforested > Murici > Caatinga; Among the areas examined, the one with lower CO2 emissions was the native Caatinga area that performed as a receiver of CO2 versus cultivated that functioned as CO2 emitter area.

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Weiss, Anna S., Anna G. Burrichter, Abilash Chakravarthy Durai Raj, Alexandra von Strempel, Chen Meng, Karin Kleigrewe, Philipp C. Münch et al. « In vitro interaction network of a synthetic gut bacterial community ». ISME Journal 16, n^o 4 (2 décembre 2021) : 1095–109. http://dx.doi.org/10.1038/s41396-021-01153-z.

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AbstractA key challenge in microbiome research is to predict the functionality of microbial communities based on community membership and (meta)-genomic data. As central microbiota functions are determined by bacterial community networks, it is important to gain insight into the principles that govern bacteria-bacteria interactions. Here, we focused on the growth and metabolic interactions of the Oligo-Mouse-Microbiota (OMM12) synthetic bacterial community, which is increasingly used as a model system in gut microbiome research. Using a bottom-up approach, we uncovered the directionality of strain-strain interactions in mono- and pairwise co-culture experiments as well as in community batch culture. Metabolic network reconstruction in combination with metabolomics analysis of bacterial culture supernatants provided insights into the metabolic potential and activity of the individual community members. Thereby, we could show that the OMM12 interaction network is shaped by both exploitative and interference competition in vitro in nutrient-rich culture media and demonstrate how community structure can be shifted by changing the nutritional environment. In particular, Enterococcus faecalis KB1 was identified as an important driver of community composition by affecting the abundance of several other consortium members in vitro. As a result, this study gives fundamental insight into key drivers and mechanistic basis of the OMM12 interaction network in vitro, which serves as a knowledge base for future mechanistic in vivo studies.

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López-García, Guadalupe, Octavio Dublan-García, Daniel Arizmendi-Cotero et Leobardo Manuel Gómez Oliván. « Antioxidant and Antimicrobial Peptides Derived from Food Proteins ». Molecules 27, n^o 4 (16 février 2022) : 1343. http://dx.doi.org/10.3390/molecules27041343.

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Recently, the demand for food proteins in the market has increased due to a rise in degenerative illnesses that are associated with the excessive production of free radicals and the unwanted side effects of various drugs, for which researchers have suggested diets rich in bioactive compounds. Some of the functional compounds present in foods are antioxidant and antimicrobial peptides, which are used to produce foods that promote health and to reduce the consumption of antibiotics. These peptides have been obtained from various sources of proteins, such as foods and agri-food by-products, via enzymatic hydrolysis and microbial fermentation. Peptides with antioxidant properties exert effective metal ion (Fe2+/Cu2+) chelating activity and lipid peroxidation inhibition, which may lead to notably beneficial effects in promoting human health and food processing. Antimicrobial peptides are small oligo-peptides generally containing from 10 to 100 amino acids, with a net positive charge and an amphipathic structure; they are the most important components of the antibacterial defense of organisms at almost all levels of life—bacteria, fungi, plants, amphibians, insects, birds and mammals—and have been suggested as natural compounds that neutralize the toxicity of reactive oxygen species generated by antibiotics and the stress generated by various exogenous sources. This review discusses what antioxidant and antimicrobial peptides are, their source, production, some bioinformatics tools used for their obtainment, emerging technologies, and health benefits.

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Vandeputte, Doris, et Marie Joossens. « Effects of Low and High FODMAP Diets on Human Gastrointestinal Microbiota Composition in Adults with Intestinal Diseases : A Systematic Review ». Microorganisms 8, n^o 11 (23 octobre 2020) : 1638. http://dx.doi.org/10.3390/microorganisms8111638.

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A diet high in non-digestible carbohydrates is known to promote health, in part through its effect on the gut microbiome. While substantially proven for healthy individuals, these effects are more ambiguous in subjects with intestinal diseases. At the same time, a diet low in these fermentable carbohydrates, the low FODMAP (acronym for Fermentable Oligo-, Di-, Mono-saccharides, And Polyols) diet, is gaining popularity as a treatment option for symptom relief in irritable bowel syndrome and inflammatory bowel disease. There are, however, several indications that this diet induces effects opposite to those of prebiotic supplementation, resulting in gut microbiome changes that might be detrimental. Here, we provide a systematic review of the effects of low and high FODMAP diets on human gastrointestinal microbiota composition in adults with intestinal diseases, through literature screening using the databases PubMed, Embase, and Web of Science. We summarize study findings on dietary impact in patients, including the effect on bacterial taxa and diversity. In general, similar to healthy subjects, restricting non-digestible carbohydrate intake in patients with intestinal diseases has opposite effects compared to prebiotic supplementation, causing a reduction in bifidobacteria and an increase in bacteria associated with dysbiosis. Future studies should focus on assessing whether the induced microbial changes persist over time and have adverse effects on long-term colonic health.

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Warnecke, Falk, Ruben Sommaruga, Raju Sekar, Julia S. Hofer et Jakob Pernthaler. « Abundances, Identity, and Growth State of Actinobacteria in Mountain Lakes of Different UV Transparency ». Applied and Environmental Microbiology 71, n^o 9 (septembre 2005) : 5551–59. http://dx.doi.org/10.1128/aem.71.9.5551-5559.2005.

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ABSTRACT The occurrence, identity, and activity of microbes from the class Actinobacteria was studied in the surface waters of 10 oligo- to mesotrophic mountain lakes located between 913 m and 2,799 m above sea level. Oligonucleotide probes were designed to distinguish between individual lineages within this group by means of fluorescence in situ hybridization (FISH). Bacteria of a single phylogenetic lineage (acI) represented >90% of all Actinobacteria in the studied lakes, and they constituted up to 70% of the total bacterial abundances. In the subset of eight lakes situated above the treeline, the community contribution of bacteria from the acI lineage was significantly correlated with the ambient levels of solar UV radiation (UV transparency, r 2 = 0.72; P < 0.01). Three distinct genotypic subpopulations were distinguished within acI that constituted varying fractions of all Actinobacteria in the different lakes. The abundance of growing actinobacterial cells was estimated by FISH and immunocytochemical detection of bromodeoxyuridine (BrdU) incorporation into de novo-synthesized DNA. The percentages of Actinobacteria with visible DNA synthesis approximately corresponded to the average percentages of BrdU-positive cells in the total assemblages. Actinobacteria from different subclades of the acI lineage, therefore, constituted an important autochthonous element of the aquatic microbial communities in many of the studied lakes, potentially also due to their higher UV resistance.

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Heluane, Humberto, Matthew R. Evans, Sue F. Dagher et José M. Bruno-Bárcena. « Meta-Analysis and Functional Validation of Nutritional Requirements of Solventogenic Clostridia Growing under Butanol Stress Conditions and Coutilization of d-Glucose and d-Xylose ». Applied and Environmental Microbiology 77, n^o 13 (20 mai 2011) : 4473–85. http://dx.doi.org/10.1128/aem.00116-11.

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ABSTRACTRecent advances in systems biology, omics, and computational studies allow us to carry out data mining for improving biofuel production bioprocesses. Of particular interest are bioprocesses that center on microbial capabilities to biotransform both the hexose and pentose fractions present in crop residues. This called for a systematic exploration of the components of the media to obtain higher-density cultures and more-productive fermentation operations than are currently found. By using a meta-analysis approach of the transcriptional responses to butanol stress, we identified the nutritional requirements of solvent-tolerant strainClostridium beijerinckiiSA-1 (ATCC 35702). The nutritional requirements identified were later validated using the chemostat pulse-and-shift technique.C. beijerinckiiSA-1 was cultivated in a two-stage single-feed-stream continuous production system to test the proposed validated medium formulation, and the coutilization ofd-glucose andd-xylose was evaluated by taking advantage of the well-known ability of solventogenic clostridia to utilize a large variety of carbon sources such as mono-, oligo-, and polysaccharides containing pentose and hexose sugars. Our results indicated thatC. beijerinckiiSA-1 was able to coferment hexose/pentose sugar mixtures in the absence of a glucose repression effect. In addition, our analysis suggests that the solvent and acid resistance mechanisms found in this strain are differentially regulated compared to strain NRRL B-527 and are outlined as the basis of the analysis toward optimizing butanol production.

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Mustad, Vikkie A., Dieu T. T. Huynh, José M. López-Pedrosa, Cristina Campoy et Ricardo Rueda. « The Role of Dietary Carbohydrates in Gestational Diabetes ». Nutrients 12, n^o 2 (31 janvier 2020) : 385. http://dx.doi.org/10.3390/nu12020385.

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Gestational diabetes (GDM) is hyperglycemia that is recognized for the first time during pregnancy. GDM is associated with a wide range of short- and long-term adverse health consequences for both mother and offspring. It is a complex disease with a multifactorial etiology, with disturbances in glucose, lipid, inflammation and gut microbiota. Consequently, its management is complex, requiring patients to self-manage their diet, lifestyle and self-care behaviors in combination with use of insulin. In addition to nutritional recommendations for all pregnant women, special attention to dietary carbohydrate (CHO) amount and type on glucose levels is especially important in GDM. Dietary CHO are diverse, ranging from simple sugars to longer-chain oligo- and poly- saccharides which have diverse effects on blood glucose, microbial fermentation and bowel function. Studies have established that dietary CHO amount and type can impact maternal glucose and nutritional recommendations advise women with GDM to limit total intake or choose complex and low glycemic CHO. However, robust maternal and infant benefits are not consistently shown. Novel approaches which help women with GDM adhere to dietary recommendations such as diabetes-specific meal replacements (which provide a defined and complete nutritional composition with slowly-digested CHO) and continuous glucose monitors (which provide unlimited monitoring of maternal glycemic fluctuations) have shown benefits on both maternal and neonatal outcomes. Continued research is needed to understand and develop tools to facilitate patient adherence to treatment goals, individualize interventions and improve outcomes.

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Davies, Gideon J., et Spencer J. Williams. « Carbohydrate-active enzymes : sequences, shapes, contortions and cells ». Biochemical Society Transactions 44, n^o 1 (9 février 2016) : 79–87. http://dx.doi.org/10.1042/bst20150186.

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The enzyme-catalysed degradation of oligo and polysaccharides is of considerable interest in many fields ranging from the fundamental–understanding the intrinsic chemical beauty–through to the applied, including diverse practical applications in medicine and biotechnology. Carbohydrates are the most stereochemically-complex biopolymer, and myriad different natural polysaccharides have led to evolution of multifaceted enzyme consortia for their degradation. The glycosidic bonds that link sugar monomers are among the most chemically-stable, yet enzymatically-labile, bonds in the biosphere. That glycoside hydrolases can achieve a rate enhancement (kcat/kuncat) >1017-fold provides testament to their remarkable proficiency and the sophistication of their catalysis reaction mechanisms. The last two decades have seen significant advances in the discovery of new glycosidase sequences, sequence-based classification into families and clans, 3D structures and reaction mechanisms, providing new insights into enzymatic catalysis. New impetus to these studies has been provided by the challenges inherent in plant and microbial polysaccharide degradation, both in the context of environmentally-sustainable routes to foods and biofuels, and increasingly in human nutrition. Study of the reaction mechanism of glycoside hydrolases has also inspired the development of enzyme inhibitors, both as mechanistic probes and increasingly as therapeutic agents. We are on the cusp of a new era where we are learning how to dovetail powerful computational techniques with structural and kinetic data to provide an unprecedented view of conformational details of enzyme action.

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Ogarkov, O. B., S. N. Zhdanova, E. A. Orlova, P. A. Khromova, N. L. Belkova, V. V. Sinkov et I. G. Kondratov. « 16S-ITS-23S rRNA operon segment sequencing provides necessary and sufficient conditions for bacterial species-specific identification ». Russian Journal of Infection and Immunity 12, n^o 5 (16 novembre 2022) : 976–80. http://dx.doi.org/10.15789/2220-7619-ros-1871.

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Introduction. Sequencing of the 16S rRNA gene is the predominant method for assessing microbial communities and strain molecular identification. The short reads (2nd generation sequencing)-based technology does not allow analysis beyond the 16S rRNA gene. The taxonomic verification level of samples usually remains at the genus or even family level. Currently, there have been proposed the latest versions of long-read technologies (Oxford Nanopore MinION, PacBio) for amplicon sequencing of near-complete ribosomal operon, including genes 16S, 23S, 5S, and internal transcribed spacer (ITS). At the moment, this approach has not been sufficiently studied, in addition, it involves PCR amplification of a very extended DNA region (more than 4000 bp-long). Materials and methods. The collection of non-tuberculous mycobacteria strains and their primary identification was carried out in the years 20192021. The strains were obtained by inoculation of positive cultures from the Bactec MGIT 960 bacteriological analyzer lacking MPT64 antigen in the MGIT TB Identification Test (Becton Dickinson, USA) on Lowenstein-Jensen medium. Preliminary species strain identification was carried out with the Speed-oligo Mycobacteria kit (Vircell, Spain) according to the manufacturers protocol. In this work, both known and newly developed universal bacterial primers flanking the near-complete 16S rRNA gene, ITS, and the beginning of the 23S rRNA gene are used. In the present study, both known and newly developed universal bacterial primers are used to flank the near-complete 16S rRNA gene, ITS, and start of the 23S rRNA gene. Results and discussion. Sanger sequencing of the amplicons (about 2000 bp) obtained shows the taxonomic level sufficient to determine species up to 8 strains of non-tuberculous mycobacteria isolated from humans that caused clinically and bacteriologically confirmed diseases. The method proposed for PCR amplification of a bacterial operon a fragment containing most of the 16S rRNA gene, ITS, and the beginning of the 23S rRNA gene is considered by us as an approbation of a methodological approach to study microbial communities in material with a high degree of degradation (necrotic foci, etc.). The results obtained indicate a significantly higher resolution of the approach used than the classical 16S rRNA gene sequencing.

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Elsharkawy, Mohsen Mohamed, Mustafa Almasoud, Yasser Mohamed Alsulaiman, Rowida S. Baeshen, Hayam Elshazly, Roqayah H. Kadi, Mohamed M. Hassan et Rady Shawer. « Efficiency of Bacillus thuringiensis and Bacillus cereus against Rhynchophorus ferrugineus ». Insects 13, n^o 10 (5 octobre 2022) : 905. http://dx.doi.org/10.3390/insects13100905.

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The Red Palm Weevil (Rhynchophorus ferrugineus (Oliv.) (Coleoptera, Dryophthoridae) is a well-known palm tree pest that has caused enormous economic damage all over the globe. Insecticides are still the primary method of controlling this pest at this period. However, field populations of RPW have been shown to be resistant to pesticides. Using Bacillus spp. might be one of the options for controlling R. ferruginous. In this study, 23 species of Bacillus spp. were isolated from the rhizosphere of date palm trees in Al Ahsa Oasis, Saudi Arabia. The isolates were identified using 16S rRNA gene sequencing. R. ferrugineus larvae and adults were tested on sugarcane pieces that were treated with the B. thuringiensis strain PDC-AHSAA1 and B. cereus strains (PDC-AHSAA2, PDC-AHSA3 and PDC-AHSA4). The LC50 values for larvae and adults were quite low when they were compared with those of the other isolated strains. The B. thuringiensis strain PDC-AHSAA1 was more effective against both the larvae and adults. The determined LC50 values for B. thuringiensis ranged from 4.19 × 107 - 3.78 × 109. After 21 days, the data on larval mortality and body weight were evaluated. The surviving larvae that were treated with the bacterial isolates did not acquire a substantial weight. For the RPW larvae and adults, the mortality and corrected mortality death rates were increased by increasing the concentration of B. thuringiensis. In conclusion, Bacillus-treated diets negatively influenced the growth and development of the RPW. This research reported on the interaction between the RPW and the rhizosphere Bacillus spp. and highlighted the tremendous potential for the development of microbial resource-based control strategies for this pest.

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Basit, Anila, Wajeeeha Syed, Nadia Ashiq Hussain, Muhammad Nasir et Laraib Aurangzeb. « Frequency of Gynecological Problems in Women on M.D.R. Tuberculosis Treatment ». Pakistan Journal of Medical and Health Sciences 16, n^o 12 (31 décembre 2022) : 410–12. http://dx.doi.org/10.53350/pjmhs20221612410.

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Multidrug-resistant TB treatment is notorious for being costly, time-consuming, and ineffective. High levels of resistance to isoniazid and rifampicin, with or without resistance to other anti-TB drugs, describe the microbial type of tuberculosis known as multidrug-resistant tuberculosis. Thirdly, MDR-TB has been shown to negatively affect mothers and infants during pregnancy, labor, and the postpartum period. Objective: This Study aimed to determine the frequency of gynecological issues among women receiving therapy for multidrug-resistant T.B. Materials and Methodology: The Obstetrics & Gynecology and department and pulmonology department of Lady Reading Hospital-MTI in Peshawar, K.P., Pakistan, collaborated on a cross-sectional descriptive study. Non-probability sequential sampling was used to get a sample size of 236 using an online G-power tool with a 95% confidence interval. Results: 236 patients were enrolled, with a range of age from 15-24 years (23.3%), 25-34 years (40.4%), 35-44 years (29.2%), and 45-54 years (6.8%). Before treatment, 56.6% were irregular. 42.4% of patients had normal periods. 66.1% had abnormal menstrual cycles after treatment. Before M.D.R. medication, 33.9% of participants had irregular menstrual cycles; throughout MDR-TB treatment, 66.1% of the population had aberrant menstrual cycles. Ploy-menorrhea was 40.7%, and oligo-menorrhea was 59.3%. four contraceptives were surveyed: 3.8% used i.u.c.d., 11.4% pills, 29.7% injectables, and 55.1% barriers. 65.7% had itching and foul-smelling vaginal discharge. 60.2% had dysmenorrhea. infertility was 62%, 55.1% primary, and 44.9% secondary. Conclusion: The Frequency of gynecological disorders that develop in women with MD-TB treatment was determined by this study. Keywords: Multidrug resistance, tuberculosis, Gynaecological problems

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Stockner, John, Arne Langston, Dale Sebastian et Greg Wilson. « The Limnology of Williston Reservoir : British Columbia's Largest Lacustrine Ecosystem ». Water Quality Research Journal 40, n^o 1 (1 février 2005) : 28–50. http://dx.doi.org/10.2166/wqrj.2005.003.

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Abstract In surface area, Williston Reservoir is British Columbia's largest lacustrine ecosystem. The reservoir shows remarkably little spatiotemporal variance among its three major reaches (Finlay, Parsnip and Peace), despite the immensity and biogeoclimatic diversity of its drainage basins. Williston is ultra-oligotrophic with average concentrations of total dissolved phosphorus (TDP) ranging from 3 to 5 µg/L and nitrate-nitrogen (NO3-N) from 60 to 65 µg/L. The pelagic plankton community of Williston Reservoir is dominated by bacteria, pico-cyanobacteria, nano-flagellates and small diatoms, and the zooplankton community is comprised largely of copepods in spring and small cladocerans in summer and fall. Primary production rates are very low and most carbon is produced by the pico- and nano-sized plankters that appear to be primarily light limited due to high turbidity and frequent wind-mixing episodes, i.e., shallow light compensation depth and deep epilimnetic depth. Microbial food webs are predominant in Williston through much of the growing season, with free-living bacteria and pico-cyanobacteria as the primary carbon template, and nano-flagellates, ciliates and micro-zooplankton as the principal grazers. Loading models indicate that after impoundment in 1968, Williston was initially a moderately productive ecosystem, but the system has progressively lost nutrients, namely P, through sedimentation and outflow, but also by the scarcity of littoral carbon production due to severe water level fluctuations (drawdown) and winter ice-scouring. Hence, within the past 2 to 3 decades the ecosystem has gradually lost biogenic productive capacity and now lies within the ultra-oligotrophic trophic status and supports a low level of fish production. Daily rates of carbon production are presently at levels more typical of British Columbia fast-flushing, ultra-oligotrophic coastal ecosystems than large, interior-type oligo- and mesotrophic British Columbia lakes. Based on average values of most limnological variables we demonstrate that the Finlay Reach is currently the most productive region of Williston, and estimates of pelagic fish from hydroacoustic/trawl and gillnet surveys support this contention.

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