Artykuły w czasopismach na temat „Rhizomic production process”
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Kravchuk, V. I., V. M. Kvak, H. V. Tsvihun, M. V. Ivaniuta, N. O. Kononiuk, O. M. Atamaniuk i Yu O. Humenyuk. "Problems of production of Miscanthus Giganteus planting material". Bioenergy, nr 1-2 (28.12.2022): 35–42. http://dx.doi.org/10.47414/be.1-2.2022.271353.
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Purpose. Justification of directions for improvement of technology and means of production of miscanthus giant planting material through in-depth analysis of theoretical and experimental domestic and international research. Method. Analytical studies of the production processes of miscanthus giant planting material. Comparison of theoretical and experimental data of the analysis of existing information, many years of production and scientific experience of cultivation, collection and preparation of planting material using modern technical means. Results. Technologies for the production of planting material in Ukraine and the leading countries of the world are shown. The promising elements of the production technology of miscanthus giant planting material are substantiated. Conclusion. The priority direction of the development of the production of miscanthus giant planting material can be based on the improved elements of the technology of the comb method of planting rhizomes and the justification of the technical means for their implementation. The improvement of technological processes requires new research, which will be related to the study of planting density in combination with uprooting of plants in a row, establishing optimal terms for harvesting biomass and digging up rhizomes, further processing of biomass with increased humidity and storage of rhizomes in field conditions (in piles).
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Mohammed, Haidar Hasan, Waham Ashaier Laftah, Akos Noel Ibrahim i Mohd Azizi Che Yunus. "Extraction of essential oil from Zingiber officinale and statistical optimization of process parameters". RSC Advances 12, nr 8 (2022): 4843–51. http://dx.doi.org/10.1039/d1ra06711g.
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The main objective of this study is to investigate the effect of process extraction variables (extraction time, volume of solvent, weight of sample) on the production of essential oil from ginger rhizome using Response Surface Methodology (RSM).
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Leonel, Magali, Priscila Aparecida Suman i Emerson Loli Garcia. "PRODUCTION OF ginger vinegar". Ciência e Agrotecnologia 39, nr 2 (kwiecień 2015): 183–90. http://dx.doi.org/10.1590/s1413-70542015000200010.
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Vinegar is a food of condiments group that have great use in the food industry. This study aimed to evaluate the effects of parameters of the acetic fermentation process in the production of ginger vinegar. A suspension of ginger rhizomes with 12% of starch was subjected to enzymatic hydrolysis process to obtain hydrolyzed with 85.6% of glucose. After the alcoholic fermentation the wine was obtained with 40.3% ethanol. The acetic fermentation process of ginger alcoholic solution followed a completely randomized design in a factorial for three factors at two levels. The independent variables were: temperature, nutrients and proportion of "strong vinegar" and alcoholic solution (initial acidity). Results showed variation from 2.74 to 3.70% for dry extract and 2.13 to 2.83 % for ash in vinegars. The profile of organic acids of ginger vinegars showed the presence of acetic, citric, malic and succinic acids in all treatments. The condition of 20°C, initial acidity 1:1,with addition of nutrients allow obtaining good quality vinegars and higher GK yields
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Rodrigues de Amorim, Antonio Carlos, i David Scott. "Learning and the Rhizome: Reconceptualisation in the Qualitative Research Process". Magis, Revista Internacional de Investigación en Educación 11, nr 22 (16.10.2018): 125–36. http://dx.doi.org/10.11144/javeriana.m11-22.lrrq.
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This article explores the concept of learning as a space of exchange and connection between signs, events and bodies, inspired by Gilles Deleuze’s philosophy of difference. This qualitative methodology is based on the rhizome, with, amongst others, its characteristics or principles of heterogeneity, multiplicity and a-signification. It allows a productive conversation with studies of learning environments and sense productions through images and sounds from cinema media, such as the swimmer and swimming. The focus of this article is on learning, its environment and its role in the relationship between mind and world, pointing to an alternative to the representational perspective.
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Gagare, Santosh, V. D. Mudgal, P. S. Champawat i Amit Pisal. "Standardization of Curing and Microwave Drying of Turmeric (Curcuma longa) Rhizomes". International Journal of Food Engineering 11, nr 2 (1.04.2015): 295–300. http://dx.doi.org/10.1515/ijfe-2014-0155.
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Abstract Curing and drying are important unit operations in turmeric processing for production of good quality products. Optimization of the process parameters for curing and microwave drying of turmeric is the need of hour for quality production of dried turmeric. These parameters were optimized by conducting trials for curing (boiling in 0.1% sodium carbonate solution for 15, 30 and 45 min) and microwave drying (power levels of 1, 1.5 and 2 kW). The cured as well as dried rhizomes were evaluated for quality parameters. The optimum boiling time for curing and power level for microwave drying of turmeric rhizomes was found to be 30 min and 1.5 kW for quality production.
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Song, Shibo, Xuanyou Chen, Mei Yang i Rongchuan Zhang. "A Drying system for Rhizoma et Radix Baphicacanthis Cusiae Based on multi-source coupling and efficient energy storag". Journal of Physics: Conference Series 2310, nr 1 (1.10.2022): 012002. http://dx.doi.org/10.1088/1742-6596/2310/1/012002.
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Abstract The traditional Chinese Herbal Medicine Rhizoma et Radix Baphicacanthis Cusiae mostly grows in Southwest China. However, due to the lack of technology, the key drying process in the production of Rhizoma et Radix Baphicacanthis Cusiae has the problems of low efficiency, long time and uneven quality. The paper designed a drying system of Rhizoma et Radix Baphicacanthis Cusiae based on multi-source coupling and efficient energy storage by investigating the production of Rhizoma et Radix Baphicacanthis Cusiae in southwest China and studying the natural effects of geographical advantages and light conditions in the region. The main body of the system is composed of a two-position water tank heat circulation system, a hemispherical Fresnel lens array, an air source heat pump, a dehumidification and waste heat recovery device, a temperature and humidity sensor, and a heat exchange tube group. The drying system can better meet the drying needs of Chinese herbal medicine Rhizoma et Radix Baphicacanthis Cusiae. It has the advantages of high efficiency, energy conservation and environmental protection, stable operation, and can independently adjust according to the drying temperature. It has strong practicability. While saving energy, it saves high drying cost for farmers, and meets the special requirements of building intelligent agriculture and enriching rural economic business forms.
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Slipchenko, G. D. "Determination of the critical parameters of the technological process of obtaining solid dosage forms with dry extract and crushed roots and rootes of Scutellaria baicalensis". Farmatsevtychnyi zhurnal, nr 3 (1.07.2019): 56–64. http://dx.doi.org/10.32352/0367-3057.3.19.07.
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An important condition for obtaining a high-quality drug is the determination of critical points and parameters of the production process, which is divided into several successive stages.
The aim study of the critical parameters of the production of tablets and capsules with vegetable raw materials. For this purpose, validation studies of technological processes were carried out for tablets with dry extract of Scutellaria baicalensis and hard gelatin capsules with vegetable raw materials.
The subject of our research was the technological process of obtaining tablets based on dry extract of the roots and rhizomes of Baikal skullcap and hard gelatin capsules based on crushed raw materials. We have identified critical process parameters for each stage. Validation tests were carried out for certain critical process parameters and acceptance criteria were calculated.
Quality control of finished tablets based on dry extract of Baikal skullcap and finished hard gelatin capsules based on crushed roots and rhizomes of Baikal skullcap was performed according to the following indicators: appearance, identification, average weight, mass uniformity, disintegration, dissolution, abrasion, microbiological purity, quantitative determination .
The obtained validation data of experimental-industrial series meet the acceptance criteria, and the developed technology is reproducible and promising for further validation.
On the basis of the obtained results, it can be concluded that the established critical values of the parameters of the production processes and their conditions of carrying out allow for stable and reliable production of semi-finished and finished products that meet the quality standards in accordance with regulatory documents.
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Bopape, Francina L., Chrizelle W. Beukes, Kopotsa Katlego, Ahmed I. Hassen, Emma T. Steenkamp i Eastonce T. Gwata. "Symbiotic Performance and Characterization of Pigeonpea (Cajanus cajan L. Millsp.) Rhizobia Occurring in South African Soils". Agriculture 13, nr 1 (22.12.2022): 30. http://dx.doi.org/10.3390/agriculture13010030.
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Pigeonpea (Cajanus cajan (L.) Millsp.) is an important grain legume, which, like several other legumes, depends on the process of biological nitrogen fixation for its nitrogen (N2) requirement by forming a symbiotic association with rhizobia. Compared to other tropical legumes, however, the productivity of pigeonpea in South Africa is low, despite the extensive interests in developing it for wider markets. To assist this process, the objectives of the current study were to (i) characterize putative indigenous rhizobial strains that were previously derived from local soils with no previous history of legume cultivation and (ii) confirm their nodulation abilities on a local landrace and a genetically improved (exotic) genotype of pigeonpea. DNA-based analyses using the 16S rRNA and recA genes showed that the strains predominantly represented Rhizobium and Bradyrhizobium, although we also recovered Phyllobacterium and Paraburkholderia. These rhizobia nodulated both the local landrace and the improved pigeonpea genotype that were included for comparative purposes. In many cases, rhizobia performed similarly on the two genotypes, although the locally sourced landrace mostly performed better in terms of nodulation and plant biomass. While the current study generated vital information regarding the diversity of indigenous rhizobia associating with pigeonpea, further screening (including field inoculation trials) would be necessary to identify possible elite nitrogen fixing rhizobial strains for development as inoculants to enhance South African pigeonpea production.
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Phachwisoot, Gittisak, Kamonwat Nakason, Chalathorn Chanthad, Pongtanawat Khemthong, Wasawat Kraithong, Saran Youngjan i Bunyarit Panyapinyopol. "Sequential Production of Levulinic Acid and Supercapacitor Electrode Materials from Cassava Rhizome through an Integrated Biorefinery Process". ACS Sustainable Chemistry & Engineering 9, nr 23 (1.06.2021): 7824–36. http://dx.doi.org/10.1021/acssuschemeng.1c01335.
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Pagano, Marcela C., Mohammad Miransari, Eduardo J. A. Corrêa, Neimar F. Duarte i Bakhytzhan K. Yelikbayev. "Genomic Research Favoring Higher Soybean Production". Current Genomics 21, nr 7 (22.10.2020): 481–90. http://dx.doi.org/10.2174/1389202921999200824125710.
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Interest in the efficient production of soybean, as one of the most important crop plants, is significantly increasing worldwide. Soybean symbioses, the most important biological process affecting soybean yield and protein content, were revitalized due to the need for sustainable agricultural practices. Similar to many crop species, soybean can establish symbiotic associations with the soil bacteria rhizobia, and with the soil fungi, arbuscular mycorrhizal fungi, and other beneficial rhizospheric microorganisms are often applied as biofertilizers. Microbial interactions may importantly affect soybean production and plant health by activating different genomic pathways in soybean. Genomic research is an important tool, which may be used to elucidate and enhance the mechanisms controlling such actions and interactions. This review presents the available details on the genomic research favoring higher soybean production. Accordingly, new technologies applied to plant rhizosphere and symbiotic microbiota, root-plant endophytes, and details about the genetic composition of soybean inoculant strains are highlighted. Such details may be effectively used to enhance soybean growth and yield, under different conditions, including stress, resulting in a more sustainable production.
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Klemencova, Katerina, Barbora Grycova i Pavel Lestinsky. "Influence of Miscanthus Rhizome Pyrolysis Operating Conditions on Products Properties". Sustainability 14, nr 10 (19.05.2022): 6193. http://dx.doi.org/10.3390/su14106193.
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Waste from the Miscanthus production cycle may be a promising source of material for the pyrolysis and biochar production. The biochar can be used to enrich the soil on which the crop grows, thus increasing productivity. A sample of Miscanthus rhizomes was used as a raw material in a series of experiments in order to find the most suitable conditions for the preparation of biochar. Miscanthus biochar was prepared in a laboratory unit using four different temperatures (i.e., 400, 500, 600 and 700 °C). All pyrolysis products were subsequently evaluated in terms of their quality and product yields were determined. For a temperature of 600 °C and a residence time of 2 h, the appropriate properties of biochar were achieved and the process was still economical. The biochar contained a minimal number of polycyclic aromatic hydrocarbons and a high percentage of carbon. Surface area was measured to be 217 m2/g. The aqueous extract of biochar was alkaline.
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Merzeau, Louise. "Digitale Fotografien: für einen öffentlichen Gedächtnisraum". Zeitschrift für Medien- und Kulturforschung 1, nr 1 (2010): 63–76. http://dx.doi.org/10.28937/1000106300.
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The modalities of the production, archiving, distribution (marketing) and societal assimilation of digital photography are producing a new economy of form and perspective. When digital photos become physical surfaces and blogs are organized into active archives, the collective public memory is transformed in the tension between two divergent poles: Privatization and standardization of photomemory in the photo data banks of large agencies on one hand, and, on the other hand rhizomatic interlacing, proliferative network memory, which, during this process, evolves into a virtual, imaginary museum. Digital photos, at this point, participate in the production of the political entity.
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González, Juan E., i Melanie M. Marketon. "Quorum Sensing in Nitrogen-Fixing Rhizobia". Microbiology and Molecular Biology Reviews 67, nr 4 (grudzień 2003): 574–92. http://dx.doi.org/10.1128/mmbr.67.4.574-592.2003.
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SUMMARY Members of the rhizobia are distinguished for their ability to establish a nitrogen-fixing symbiosis with leguminous plants. While many details of this relationship remain a mystery, much effort has gone into elucidating the mechanisms governing bacterium-host recognition and the events leading to symbiosis. Several signal molecules, including plant-produced flavonoids and bacterially produced nodulation factors and exopolysaccharides, are known to function in the molecular conversation between the host and the symbiont. Work by several laboratories has shown that an additional mode of regulation, quorum sensing, intercedes in the signal exchange process and perhaps plays a major role in preparing and coordinating the nitrogen-fixing rhizobia during the establishment of the symbiosis. Rhizobium leguminosarum, for example, carries a multitiered quorum-sensing system that represents one of the most complex regulatory networks identified for this form of gene regulation. This review focuses on the recent stream of information regarding quorum sensing in the nitrogen-fixing rhizobia. Seminal work on the quorum-sensing systems of R. leguminosarum bv. viciae, R. etli, Rhizobium sp. strain NGR234, Sinorhizobium meliloti, and Bradyrhizobium japonicum is presented and discussed. The latest work shows that quorum sensing can be linked to various symbiotic phenomena including nodulation efficiency, symbiosome development, exopolysaccharide production, and nitrogen fixation, all of which are important for the establishment of a successful symbiosis. Many questions remain to be answered, but the knowledge obtained so far provides a firm foundation for future studies on the role of quorum-sensing mediated gene regulation in host-bacterium interactions.
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Motoki, Satoru, Takumi Taguchi, Ayaka Kato, Katsuhiro Inoue i Eiji Nishihara. "Distribution of Growth-inhibitory Activity, Mineral Contents, and Functional Components in Different Tissue Parts of Asparagus (Asparagus officinalis L.) and Availability of Unusable Parts". HortScience 56, nr 11 (listopad 2021): 1340–46. http://dx.doi.org/10.21273/hortsci16057-21.
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Asparagus is a popular vegetable rich in healthy functional components. However, the process of its production leaves ferns from aboveground parts and roots from underground parts as unusable parts, and this is an issue to be resolved. In our previous studies, large amounts of rutin were noted in the cladophylls and storage roots (brown and epidermis), and the protodioscin content was high in buds, in the soil-covered section of spears, and in rhizomes. This study was conducted to examine the distribution of growth-inhibitory activity and mineral contents in different parts of asparagus. Correlations, including representative functional components (rutin and protodioscin), were examined. The results suggest there are differences in growth-inhibitory activity of different parts of asparagus. The growth-inhibitory activity was strong in the buds, rhizome, and absorptive and storage roots, and weak in the cladophylls and lateral branches. The percent N content of the aboveground part of asparagus was high compared with that in the aboveground part of other crops. Although the percent K content was similar to the mean of the aboveground part of other crops, it was higher than that in general green manure, suggesting the residual stems and leaves of the aboveground part of asparagus are effective green manure. In the aboveground part of asparagus, the rutin content and percent N and K content were higher, whereas growth-inhibitory activity tended to be low, suggesting that when no disease developed in the aboveground part, it can be used as an organic substance.
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SUN, Wenli, i Mohamad H. SHAHRAJABIAN. "The effectiveness of Rhizobium bacteria on soil fertility and sustainable crop production under cover and catch crops management and green manuring". Notulae Botanicae Horti Agrobotanici Cluj-Napoca 50, nr 2 (23.05.2022): 12560. http://dx.doi.org/10.15835/nbha50212560.
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The ability of adaptation of Rhizobia in diverse environment namely, soil, rhizosphere and grown within legume roots may lead to nitrogen fixation, in a complicated process which contain a coordinated exchange of signal between plants and the symbionts. Green manures, cash and cover crops have significant role in soil fertility. Green manuring techniques also can decrease biomass burning known as main source of air pollutant in the atmosphere. Catch crops have positive effects on both physical and chemical properties of soil, subsequent crop yield, decrease nitrogen leaching into the ground water, decrease soil erosion, and decrease nitrogen losses in cropping systems. Cover crops are those crops which cover the ground and protect loss of plant nutrients, the soil from erosion, decrease rate of soil moisture by evaporation, lower ground temperature and improve weed control and nutrient recycling. Rhizobia produce Nod factors during the early development of nodules upon perception of flavonoid molecules secreted by legume roots, and Nod factor’s structure dependents on species, chemical, substitutions added which may influence legume specificity. The benefic effects of rhizobia may depend on rhizobium strain, the genotype of the legume, management practices and bio-physical environment. Rhizobium can directly promote both plant growth and plant health, and modulating root architecture and growth via the release of plant phytohormones. In this manuscript, we want to review the most important advantages and benefits of green manures, catch and cover crops with considering the positive effects of rhizobium on soil fertility and sustainable agricultural production.
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Biffi, Alfredo, Rita Bissola i Barbara Imperatori. "Chasing innovation: a pilot case study of a rhizomatic design thinking education program". Education + Training 59, nr 9 (9.10.2017): 957–77. http://dx.doi.org/10.1108/et-01-2016-0007.
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Purpose The purpose of this paper is to illustrate and discuss the main features and key challenges of an original post-graduate education program designed according to an innovative theoretical framework promoting design thinking in a rhizomatic approach. By involving different stakeholders, the aim of this entrepreneurship education program is to disseminate rhizomatic, design-based learning competencies and thereby contribute to revitalizing a region’s socio-economic fabric. Design/methodology/approach Through the use of a pilot case, the paper exemplifies the application of the design thinking approach combined with the rhizomatic logic. Design thinking enables dealing with the complexity, uncertainty, and ill-defined problems that often characterize a business reality while the rhizomatic process combines the production of collective knowledge through a non-linear, complex and emergent path that nurtures innovation. Findings This entrepreneurship education program exemplifies a viable strategy to deal with a regional economic crisis by engaging different local actors including enterprises, local institutions, municipalities, and universities. It demonstrates the potential value of a new educational approach as a powerful lever to activate the energy of people, their competencies, relationships, shared projects, and new entrepreneurial ventures. The first edition of the program offers ideas, practices, and challenges to all stakeholders of potentially similar education projects. Originality/value The depicted pilot case allows us to exemplify how a design thinking framework reinterpreted on the basis of a Deleuzian rhizomatic perspective can enable developing innovation as a way of overcoming difficulties and succeeding, an essential prerequisite for many entrepreneurial organizations today.
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Khmelevskaya, A. V., I. T. Karaeva, S. K. Cherchesova i V. N. Sorokopudov. "Justification of the feasibility of using wild-growing inulin-containing plants in bread technology". IOP Conference Series: Earth and Environmental Science 1010, nr 1 (1.04.2022): 012154. http://dx.doi.org/10.1088/1755-1315/1010/1/012154.
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Abstract This article discusses the use of additives from the roots and rhizomes of inulin-containing plants in baking. A method has been developed for the production of bread with the addition of powders of wild-growing inulin-containing plants at a dosage of 1.5%, which makes it possible to obtain a new type of bread while reducing the consumption of baker’s yeast by 10-15%, or reducing the duration of dough fermentation by 15-20%. The content of inulin in 100 g of bread made from wheat flour with the addition of 1.5% to the mass of high elecampane powder is 0.41 g/100 g (S.V.), the fructose content is 0.35 g/100 g (S.V. ). It was found that the added additives do not reduce the microbiological safety of bread. So, QMAFAnM in the sample with high elecampane - 3.5 × 102, in the sample with dandelion officinalis - 1.0 × 102, in the sample with greater burdock 2.3 × 102, which meets the requirements of SanPiN. The quality indicators of powders from roots and rhizomes have been determined, their influence on the technological process of bread production has been studied. A rational dosage was established in the amount of 1.5% by weight of flour, which makes it possible to obtain bread with high quality indicators, increased nutritional value.
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Provorov, N. A., U. B. Saimnazarov, I. U. Bahromov, D. Z. Pulatova, A. P. Kozhemyakov i G. A. Kurbanov. "Effect of rhizobia inoculation on the seed (herbage) production of mungbean (Phaseolus aureusRoxb.) grown at Uzbekistan". Journal of Arid Environments 39, nr 4 (sierpień 1998): 569–75. http://dx.doi.org/10.1006/jare.1998.0379.
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Lorkiewicz, Z. "Nodulation genes in the Rhizobium--plant signal exchange." Acta Biochimica Polonica 44, nr 1 (31.03.1997): 1–12. http://dx.doi.org/10.18388/abp.1997_4434.
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The process of the host-plant recognition by rhizobia is complex and multi-step. The interaction between legumes and microorganisms results in the induction of the root nodule. This symbiotic interaction is highly host-specific. Bacteria within nodules fix atmospheric nitrogen. This process is of immense ecological and economic significance. The subject of this presentation is the molecular mechanism by which the bacterium determines its host-specific characteristics. First flavonoids secreted by the plant roots induce the transcription of bacterial genes involved in nodulation, the so-called nod genes. This leads to the next step of the signalling system, i.e. the production and secretion of lipo-oligosaccharide molecules by rhizobia. These signal molecules have various discernible effects on the roots of the host leguminous plants. The bacterial nodulation factors were isolated and structurally identified as substituted and N-acylated chitin oligosaccharides. These prokaryotic signals play a key role in the symbiosis by controlling the host specificity of the bacteria. They constitute a new class of signalling molecules able to elicit nodule organogenesis in leguminous plants in the absence of bacteria. More recent studies implicate involvement of root cell membrane depolarization and ion selective channels in the communication processes that initiate nodule formation.
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Gharzouli, Razika, Marie-Anne Carpéné, François Couderc, Ammar Benguedouar i Véréna Poinsot. "Relevance of Fucose-Rich Extracellular Polysaccharides Produced by Rhizobium sullae Strains Nodulating Hedysarum coronarium L. Legumes". Applied and Environmental Microbiology 79, nr 6 (26.11.2012): 1764–76. http://dx.doi.org/10.1128/aem.02903-12.
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ABSTRACTSpecific and complex interactions between soil bacteria, known as rhizobia, and their leguminous host plants result in the development of root nodules. This process implies a complex dialogue between the partners. Rhizobia synthesize different classes of polysaccharides: exopolysaccharides (EPS), Kdo-rich capsular polysaccharides, lipopolysaccharides, and cyclic β-(1,2)-glucans. These polymers are actors of a successful symbiosis with legumes. We focus here on studying the EPS produced byRhizobium sullaebacteria that nodulateHedysarum coronariumL., largely distributed in Algeria. We describe the influence of the carbon source on the production and on the composition of EPS produced byR. sullaeA6 and RHF strains. High-molecular-weight EPS preserve the bacteria from desiccation. The structural characterization of the EPS produced byR. sullaestrains has been performed through sugar analysis by gas chromatography-mass spectrometry. The low-molecular-weight EPS of one strain (RHF) has been totally elucidated using nuclear magnetic resonance and quantitative time-of-flight tandem mass spectrometry analyses. An unusual fucose-rich EPS has been characterized. The presence of this deoxy sugar seems to be related to nodulation capacity.
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Chen, Wei, Long Luo, Lin-Yan He, Qi Wang i Xia-Fang Sheng. "Distinct Mineral Weathering Behaviors of the Novel Mineral-Weathering Strains Rhizobium yantingense H66 and Rhizobium etli CFN42". Applied and Environmental Microbiology 82, nr 14 (29.04.2016): 4090–99. http://dx.doi.org/10.1128/aem.00918-16.
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ABSTRACTBacteria play important roles in mineral weathering, soil formation, and element cycling. However, little is known about the interaction between silicate minerals and rhizobia. In this study,Rhizobium yantingenseH66 (a novel mineral-weathering rhizobium) andRhizobium etliCFN42 were compared with respect to potash feldspar weathering, mineral surface adsorption, and metabolic activity during the mineral weathering process. Strain H66 showed significantly higher Si, Al, and K mobilization from the mineral and higher ratios of cell numbers on the mineral surface to total cell numbers than strain CFN42. Although the two strains produced gluconic acid, strain H66 also produced acetic, malic, and succinic acids during mineral weathering in low- and high-glucose media. Notably, higher Si, Al, and K releases, higher ratios of cell numbers on the mineral surface to total cell numbers, and a higher production of organic acids by strain H66 were observed in the low-glucose medium than in the high-glucose medium. Scanning electron microscope analyses of the mineral surfaces and redundancy analysis showed stronger positive correlations between the mineral surface cell adsorption and mineral weathering, indicated by the dissolved Al and K concentrations. The results showed that the two rhizobia behaved differently with respect to mineral weathering. The results suggested thatRhizobium yantingenseH66 promoted potash feldspar weathering through increased adsorption of cells to the mineral surface and through differences in glucose metabolism at low and high nutrient concentrations, especially at low nutrient concentrations.IMPORTANCEThis study reported the potash feldspar weathering, the cell adsorption capacity of the mineral surfaces, and the metabolic differences between the novel mineral-weatheringRhizobium yantingenseH66 andRhizobium etliCFN42 under different nutritional conditions. The results showed thatRhizobium yantingenseH66 had a greater ability to weather the mineral in low- and high-glucose media, especially in the low-glucose medium. Furthermore,Rhizobium yantingenseH66 promoted mineral weathering through the increased adsorption of cells to the mineral surface and through increased organic acid production. Our results allow us to better comprehend the roles of different rhizobia in silicate mineral weathering, element cycling, and soil formation in various soil environments, providing more insight into the geomicrobial contributions of rhizobia to these processes.
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Ma, Junnan, Seok Yong Kang, Xianglong Meng, An Na Kang, Jong Hun Park, Yong-Ki Park i Hyo Won Jung. "Effects of Rhizome Extract of Dioscorea batatas and Its Active Compound, Allantoin, on the Regulation of Myoblast Differentiation and Mitochondrial Biogenesis in C2C12 Myotubes". Molecules 23, nr 8 (13.08.2018): 2023. http://dx.doi.org/10.3390/molecules23082023.
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With the aging process, a loss of skeletal muscle mass and dysfunction related to metabolic syndrome is observed in older people. Yams are commonly use in functional foods and medications with various effects. The present study was conducted to investigate the effects of rhizome extract of Dioscorea batatas (Dioscoreae Rhizoma, Chinese yam) and its bioactive compound, allantoin, on myoblast differentiation and mitochondrial biogenesis in skeletal muscle cells. Yams were extracted in water and allantoin was analyzed by high performance liquid chromatography (HPLC). The expression of myosin heavy chain (MyHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), sirtuin-1 (Sirt-1), nuclear respiratory factor-1 (NRF-1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) or western blot. The glucose levels and total ATP contents were measured by glucose consumption, glucose uptake and ATP assays, respectively. Treatment with yam extract (1 mg/mL) and allantoin (0.2 and 0.5 mM) significantly increased MyHC expression compared with non-treated myotubes. Yam extract and allantoin significantly increased the expression of PGC-1α, Sirt-1, NRF-1 and TFAM, as well as the phosphorylation of AMPK and ACC in C2C12 myotubes. Furthermore, yam extract and allantoin significantly increased glucose uptake levels and ATP contents. Finally, HPLC analysis revealed that the yam water extract contained 1.53% of allantoin. Yam extract and allantoin stimulated myoblast differentiation into myotubes and increased energy production through the upregulation of mitochondrial biogenesis regulators. These findings indicate that yam extract and allantoin can help to prevent skeletal muscle dysfunction through the stimulation of the energy metabolism.
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Ogbu, C. C., S. Ndifereke i N. N. Ogbu. "Response of laying hens to dietary ginger (Zingiber officinale) rhizome powder supplementation pre- and post moulting". Nigerian Journal of Animal Production 49, nr 3 (16.05.2022): 78–101. http://dx.doi.org/10.51791/njap.v49i3.3576.
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Induced moulting in hens generate enormous physiological stress which compromises health, post moult performance, and food safety. To minimize moulting stress and mitigate its negative impacts, requires the adoption of management practices that reduce microbial infection, and spread, and enhance performance before, during, and after moulting. The present study therefore, evaluated the effects of ginger (Zingiber officinale) rhizome powder dietary supplementation on pre- and post-moult performance of shaver brown (SB) and indigenous (IC) layer chickens (85 weeks of age, 65 weeks in lay). The study was in three phases namely Phase I: pre-moulting evaluation, phase II: moulting treatment, and phase III: post moult evaluation. For each study, birds received 12 h natural light, and darkness, and were housed in individual laying cages provided with water nipples and feeding trough. Parameters measured were body weight (BW), hen day egg production (HDEP), and egg weight (EW). Results showed improved pre- and post-moult BW, HDEP, and EW in both genotypes in the groups fed dietary ginger powder. Genotypes did not differ significantly within dietary groups in the studied traits. Fasted SB hens fed ginger diet oviposited earlier than counterparts fed basal diet but the latter group attained 50 % HDEP earlier. Moulting BW loss was higher in fasted birds and in birds fed ginger diet pre-moulting than those fed basal diet. Whereas fasted SB hens oviposited during the period of study, the IC could not. Laying attained 100 % in Zn moulted genotypes and 66.8 % in fasted SB within 21 d post moulting. It is concluded that high dietary Zn is equally effective as fasting in moulting aged layer chickens and that ginger rhizome powder dietary supplementation improves pre- and post moult performance of laying hens. A shorter than 14 days moulting treatment or moulting to a target body weight loss is recommended for light breeds like the IC to enhance recovery and early postmoult egg production.
La mue induite chez les poules génère un énorme stress physiologique qui compromet la santé, les performances après la mue et la sécurité alimentaire. Pour minimiser le stress de la mue et atténuer ses impacts négatifs, il faut adopter des pratiques de gestion qui réduisent l'infection microbienne et la propagation, et améliorent les performances avant, pendant et après la mue. La présente étude a donc évalué les effets de la supplémentation alimentaire en poudre de rhizome de gingembre (Zingiber officinale) sur les performances avant et après la mue des poules pondeuses brunes (PB) et indigènes (IC) (85 semaines d'âge, 65 semaines de ponte) . L'étude s'est déroulée en trois phases, à savoir la phase I : évaluation avant la mue, la phase II : traitement de la mue et la phase III : évaluation après la mue. Pour chaque étude, les oiseaux ont reçu 12 h de lumière naturelle et d'obscurité, et ont été logés dans des cages de ponte individuelles munies de tétines d'eau et d'abreuvoirs. Les paramètres mesurés étaient le poids corporel (PC), la production d'œufs par jour de poule (PŒJP) et le poids des œufs (PŒ). Les résultats ont montré une amélioration du poids corporel, du PŒJP et de le PŒ avant et après la mue pour les deux génotypes dans les groupes nourris avec de la poudre de gingembre alimentaire. Les génotypes ne différaient pas significativement au sein des groupes alimentaires dans les traits étudiés. Les poules PB à jeun nourries au gingembre ont pondu plus tôt que leurs homologues nourries au régime de base, mais ce dernier groupe a atteint 50 % de PŒJP plus tôt. La perte de poids corporel pendant la mue était plus élevée chez les oiseaux à jeun et chez les oiseaux nourris au gingembre avant la mue que chez ceux nourris avec un régime de base. Alors que les poules PB à jeun ont pondu pendant la période d'étude, l'IC ne le pouvait pas. La ponte a atteint 100 % chez les génotypes mués Zn et 66,8 % chez les PB à jeun dans les 21 jours suivant la mue. Il est conclu qu'une alimentation riche en Zn est aussi efficace que le jeûne chez les poules pondeuses âgées en mue et que la supplémentation alimentaire en poudre de rhizome de gingembre améliore les performances avant et après la mue des poules pondeuses. Un traitement de mue de moins de 14 jours ou une mue vers une perte de poids cible est recommandé pour les races légères comme l'IC afin d'améliorer la récupération et la production d'œufs après la mue.
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Kębłowska-Ławniczak, Ewa. "Liminal hypotext‐hypertext relations in selected Shakespearean prequels, sequels and gap-fillers". Journal of Adaptation in Film & Performance 14, nr 1 (1.03.2021): 87–107. http://dx.doi.org/10.1386/jafp_00044_1.
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Liminality is inherent in the adaptation process situated ‘in-between’. Proposing the ‘biological’ concept of symbiosis, David Cowart distinguishes between the ‘host’ and the ‘guest’ text. Symbiosis as a shape-shifting concept involves a two-directional adaptation process, an ‘epistemic dialogue’, where interest is in how the later text’s meaning is produced in relation to the earlier and how the overall production of meaning is affected by the hypertext. To obliterate the lines of influence, temporal distance, privilege and importance, it is possible to conceive of the relation between hypotext and the hypertextual ‘attachment’ as rhizomatic and thus to locate the ‘hypertext product’ in a region where historical genealogies either no longer matter or need to be seriously reconceptualized The article discusses the hypotext‐hypertext relations in a selection of modern and postmodern adaptations by Maurice Baring, Gordon Bottomley, WTG and Elaine Feinstein and Linda Bamber, as ‘symbiotic attachments’ or rhizomatic developments whose relationship with the Shakespearean text, or rather ‘aggregate’ can be variously defined in narrative terms. I argue that texts located in the position of prologues, epilogues or separately published ‘letters’ ‐ defined as prequels, sequels or gap-fillers and often pointing to an ontological or temporal elsewhere ‐ can be variously defined as elements of the main text, metatexts masquerading as paratexts or framing borders and that they function as generators of meaning.
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Becquart-de Kozak, Isabelle, Bradley L. Reuhs, Dominique Buffard, Colette Breda, John S. Kim, Robert Esnault i Adam Kondorosi. "Role of the K-Antigen Subgroup of Capsular Polysaccharides in the Early Recognition Process Between Rhizobium meliloti and Alfalfa Leaves". Molecular Plant-Microbe Interactions® 10, nr 1 (styczeń 1997): 114–23. http://dx.doi.org/10.1094/mpmi.1997.10.1.114.
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We used a model system to investigate the induction of plant genes by bacterial surface compounds. We have infiltrated alfalfa leaves with wild-type Rhizobium meliloti strain Rm41 and mutant derivatives, which are deficient in the production of exopolysaccharides (EPS), capsular K-polysaccharides (KPS or K-Antigens), or both. We have shown that wild-type R. meliloti was able to induce transcript accumulation of genes encoding enzymes of the iso-flavonoid biosynthetic pathway: chalcone synthase (CHS), chalcone reductase (CHR), and isoflavone reductase (IFR). Kinetics of these transcript accumulations were biphasic, occurring 0.75 to 1.5 h and 6 to 30 h after treatment. The exoB derivative of Rm41 (strain AK631), which is unable to produce either EPS I or EPS II, was still able to induce very rapid (45-min posttreatment) transcript accumulation of CHS and CHR genes. These results suggested that EPS were not involved in this induction. We then tested three R. meliloti fix-23 mutants (strains PP699, PP711, and PP671), which were deficient in KPS production as shown by PAGE and immunoblot analyses. In contrast to the results obtained with the mutant strains, infiltration of alfalfa leaves with purified KPS, isolated from strain AK631, led to a very rapid induction of the CHS and CHR genes. Therefore, we hypothesize that KPS may play a role in the early recognition of rhizobia by the leaf cells.
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Dražić, Gordana, Mirjana Aranđelović, Jelena Milovanović, Zuzana Jureková i Eleonóra Marišová. "Potentials For Agro-Energy Crops Production: Example Of Miscanthus Cultivation In Serbia". Acta Regionalia et Environmentalica 12, nr 2 (1.11.2015): 30–37. http://dx.doi.org/10.1515/aree-2015-0007.
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Abstract In accordance with priorities of sustainable development in Serbia, production and use of biomass is crucial for provision of annually renewable national sources of energy and for environmental quality conservation. Rural development has typically focused on improving agricultural production and promoting market orientation, however, as the examples of other countries in the EU accession process have shown (e.g. Slovakia), such an approach could threaten the survival of rural population. Biomass production is one of the key sectors with significant potential for diversification of rural economy. The results of multiannual research work supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia through national scientific projects and several international initiatives are summarized in this paper. The research activities focus on Miscanthus × giganteus Greef et Deu. The production potentials of miscanthus on fertile and degraded soils were investigated since 2009 in experimental plots established on moderate and extremely degraded lands in Serbia, applying various agrotechnical measures in different ecological conditions. The results show that fertile agricultural land as well as moderate degraded areas provide suitable conditions for miscanthus biomass and viable rhizomes production for energy and ecoremediation purposes.
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Yuliana, Yayuk, Wan Dian Safina i Minda Sari Lubis. "PKM Development of Herb Business Traditional Buffer Area Forest Leuser". PKM-P 6, nr 2 (7.12.2022): 406. http://dx.doi.org/10.32832/jurma.v6i2.1583.
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The Tambar Malem group, which currently consists of housewives still producing traditional Karo concoctions. This group is located in Batu Katak Hamlet, Batu Jong Jong Village. Potions- potions produced by the Medicinal Plant Cultivation Group and produce it Becomes worthy for for sale moment it still is belong simple. Plant The ingredients cultivated are turmeric, galangal, kencur, bengle, temu Kunci, lemon grass, wake-up leaves. get up and other types. Materials are collected from the garden or purchased and then washed and cleaned then processed manually using simple tools such as machetes, knives and swallow. The nutritious rhizomes and leaves are chopped on the chopping board with a machete. After it is felt that these ingredients get the desired texture as a whole the ingredients are mixed into one so that the ingredients are evenly mixed. After this process, do it drying that still relies on solar energy to dry the material. that way is one of the process of making spray. The problems faced are the method of production, still using traditional methods. In production still use simple tools and manual so the amount of production is still small. Methods of implementation using education and counseling, and training. Solutions to partner priority problems from Aspect production ie with procurement and use of equipment. The result achieved is an increase in the quality of the herb product.
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Yuliana, Yayuk, Wan Dian Safina i Minda Sari Lubis. "PKM Development of Herb Business Traditional Buffer Area Forest Leuser". PKM-P 6, nr 2 (7.12.2022): 406. http://dx.doi.org/10.32832/pkm-p.v6i2.1583.
Pełny tekst źródłaStreszczenie:
The Tambar Malem group, which currently consists of housewives still producing traditional Karo concoctions. This group is located in Batu Katak Hamlet, Batu Jong Jong Village. Potions- potions produced by the Medicinal Plant Cultivation Group and produce it Becomes worthy for for sale moment it still is belong simple. Plant The ingredients cultivated are turmeric, galangal, kencur, bengle, temu Kunci, lemon grass, wake-up leaves. get up and other types. Materials are collected from the garden or purchased and then washed and cleaned then processed manually using simple tools such as machetes, knives and swallow. The nutritious rhizomes and leaves are chopped on the chopping board with a machete. After it is felt that these ingredients get the desired texture as a whole the ingredients are mixed into one so that the ingredients are evenly mixed. After this process, do it drying that still relies on solar energy to dry the material. that way is one of the process of making spray. The problems faced are the method of production, still using traditional methods. In production still use simple tools and manual so the amount of production is still small. Methods of implementation using education and counseling, and training. Solutions to partner priority problems from Aspect production ie with procurement and use of equipment. The result achieved is an increase in the quality of the herb product.
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Jasper, DA. "Bioremediation of agricultural and forestry soils with symbiotic microorganisms". Soil Research 32, nr 6 (1994): 1301. http://dx.doi.org/10.1071/sr9941301.
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Symbiotic micro-organisms are important in alleviating the limitations of nitrogen and phosphorus deficiency on plant growth in Australian soils. Maximization of the contribution of these micro-organisms can give important benefits for plant production. In some cases, optimization of the infectivity of the target organisms will be achieved most effectively through changing soil management stratregies. In soils where the infective organisms are absent, or where the indigenous isolates are not effective, inoculation with selected isolates may be appropriate. Adoption of inoculation technology depends on a well defined benefit and a reliable source of high quality inoculum at a cost which is appropriate for the overall cost structure and returns of the industry. Further, inoculation should not require additional complex technology or machinery and should fit easily into existing processes of production. Inoculation with rhizobia in legume production meets these criteria and consequently is widely used. By contrast, inoculation with VA or ectomycorrhizal fungi still only occurs on a small scale, in part due to practical difficulties of inoculum production but also due to the limited number of situations where the benefits of inoculation can be clearly demonstrated.
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Stamford, Newton Pereira, Patrícia Ribeiro dos Santos, Adriana Muniz Mendes Freire de Moura, Carolina Etiene de Rosália e. Silva Santos i Ana Dolores Santiago de Freitas. "Biofertilzers with natural phosphate, sulphur and Acidithiobacillus in a siol with low available-P". Scientia Agricola 60, nr 4 (grudzień 2003): 767–73. http://dx.doi.org/10.1590/s0103-90162003000400024.
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The production of mineral fertilizers is a expensive process, since it requires high energy consumption, and cannot be produced by small farmers. Laboratory assays were conducted to produce P-biofertilizers from natural phosphate (B5, B10, B15, B20), applying sulphur at different rates (5; 10; 15 and 20%) inoculated with Acidithiobacillus (S*) and testing increasing periods of incubation. A greenhouse experiment was carried out to evaluate the effect of the biofertilizers in a soil with low available P (Typic Fragiudult) from the "Zona da Mata" of Pernambuco State, grown with yam bean (Pachyrhizus erosus) in two consecutive harvests. The treatments were: Natural Phosphate (NP); biofertilizers produced in laboratory (B5, B10, B15, B20) with sulphur and Acidithiobacillus (NP+S*); natural phosphate with sulphur (20%) without Acidithiobacillus (NP+S); triple super phosphate (TSP) and a control without phosphorus. Plants were inoculated with a mixture of rhizobia strains (NFB 747 and NFB 748) or did not receive rhizobia inoculation. In bioassays pH and available P in the biofertilizers were analyzed. In the greenhouse experiment shoot dry matter, total N and total P in shoots, soil pH and available P were determined. Higher rates of available P were obtained in biofertilizers with sulphur and Acidithiobacillus (NP+S*) and in triple super phosphate (TSP), and biofertilizers with sulphur and Acidithiobacillus (FN+S*) and triple super phosphate (TSP) increased plant parameters. Native rhizobia were as effective as the strains applied in inoculation. After the two harvests soil presented lower pH values and higher rates of available P when the biofertilizers B15 and B20 with sulphur and Acidithiobacillus were applied.
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Langergraber, G., R. Haberl, J. Laber i A. Pressl. "Evaluation of substrate clogging processes in vertical flow constructed wetlands". Water Science and Technology 48, nr 5 (1.09.2003): 25–34. http://dx.doi.org/10.2166/wst.2003.0272.
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Substrate clogging is by far the biggest operational problem of vertical flow constructed wetlands. The term “substrate clogging” summarises several processes which lead to reduction of the infiltration capacity at the substrate surface. The lower infiltration rate causes a reduced oxygen supply and further leads to a rapid failure of the treatment performance. Reasons for substrate clogging include accumulation of suspended solids, surplus sludge production, chemical precipitation and deposition in the pores, growth of plant-rhizomes and roots, generation of gas and compaction of the clogging layer. However, it is not clear how much each process contributes to the clogging process. Detailed investigations were carried out at pilot-scale constructed wetlands (PSCWs) using a variety of methods: e.g. soil physical investigations, microbial methods, and various analysis methods of drinking water and wastewater. The paper shows the results of these investigations and presents an equation to calculate the theoretical clogging time.
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Lin, Li-Yun, Kun-Hung Shen, Xiang-Yü Yeh, Bou-Yü Huang, Hui-Er Wang, Kuan-Chou Chen i Robert Y. Peng. "Integrated Process for Production of Galangal Acetate, the “Wasabi-Like” Spicy Compound, and Analysis of Essential Oils of Rhizoma Alpinia officinarum (Hance) Farw". Journal of Food Science 81, nr 6 (11.05.2016): H1565—H1575. http://dx.doi.org/10.1111/1750-3841.13326.
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Sheida, E. V., V. A. Ryazanov, K. S. Denisenko i O. V. Shoshina. "Changes in the concentration of methane in the ecosystem in vitro against the background of Asteraceae family plants biomass". BIO Web of Conferences 42 (2022): 01015. http://dx.doi.org/10.1051/bioconf/20224201015.
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The assessment of Asteráceae Family Plants (rhizomes and roots of elecampane and wormwood) influence on the process of methane formation in the rumen ecosystem and metabolic processes was carried out. Studies (in vitro) were carried out using ANKOM Daisy II incubator (modifications D200 and D200I) according to a specialized method. Rumen contents were obtained from beef bulls with chronic rumen fistula. Gas analysis of air and volatile fatty acids samples was performed by gas chromatography. The results of the study showed that different dosages of phytobiotic preparations did not significantly affect the characteristics of fermentation in vitro. Phytobiotic preparations of elecampane and wormwood reduce the production of methane in the ruminal fluid, which may be associated with various active components or dosages of their administration.
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Ferreira Lopes, Patricia. "The production of the rail system. Towards a historical IDE of rail heritage of Andalusia". Virtual Archaeology Review 6, nr 13 (24.11.2015): 41. http://dx.doi.org/10.4995/var.2015.4371.
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<p>The railway process (1854-1940) in Andalucia contributed to the formation of a new territorial structure. The railway, built and used, was also a means of production: business networks, flows of raw materials and people, energy technologies that shaped the land and also were shaped by it. In this sense, the railroad, produced and producer of various changes, cannot be understood without its productive forces, including knowledge and technology, the working class, the superstructure of society, the State and nether can't be separated from nature, where the topography and hydrology played important role. These factors are combined, juxtaposed, are interspersed, engage and sometimes collide, creating what might be called the " rail rhizome", a hyper complex space, intervened and shaped by a diversity of actors.<br />This paper presents a new interpretation of the Andalucia railway heritage through the application of a Geographic Information System (GIS), which based on the historical creation of a spatial data infrastructure (SDI) of railways in Andalucia, open and expands its spatiotemporal vision.</p>
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YU, O. T., i G. L. CHMURA. "Soil carbon may be maintained under grazing in a St Lawrence Estuary tidal marsh". Environmental Conservation 36, nr 4 (grudzień 2009): 312–20. http://dx.doi.org/10.1017/s0376892910000184.
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SUMMARYProduction of belowground organic matter is critical to sustainability of salt marshes. It plays a role in vertical soil accretion, a process essential for salt marshes to maintain their relative elevation and persist as sea levels rise. This paper examines belowground production and soil carbon of a high-latitude saltmarsh in the St Lawrence Estuary (Québec, Canada), which had been subjected to six years of sheep grazing. In the seventh year, without sheep, organic matter production in grazed and ungrazed sections was assessed by examining harvests of plant litter, end-of-season standing crop, and the roots and rhizomes present in in-growth cores. Excepting salinity, porewater chemistry varied little. The grazed marsh had higher soil carbon density and belowground production, yet lower aboveground biomass. Grazing reduces plant litter and increases solar exposure, soil temperature (at this latitude, soil remained frozen until April) and evapotranspiration, thus raising soil salinity and nitrogen demand, the latter a driver of root production. Grazing may not be detrimental to soil carbon storage. Permitting certain types of grazing on restored salt marshes previously drained for agriculture would provide economic incentive to restore tidal flooding, because the natural carbon sink provided in the recovered marsh would make these lands eligible for carbon payments.
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Hwang, Sun Mi, Yun Jung Lee, Dae Gill Kang i Ho Sub Lee. "Anti-Inflammatory Effect of Gastrodia elata Rhizome in Human Umbilical Vein Endothelial Cells". American Journal of Chinese Medicine 37, nr 02 (styczeń 2009): 395–406. http://dx.doi.org/10.1142/s0192415x09006916.
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Vascular inflammation is a pivotal factor of a variety of diseases, such as atherosclerosis and tumor progression. The present study was designed to examine the anti-inflammatory effect of ethanol extract of Gastrodia elata rhizome (EGE) in primary cultured human umbilical vein endothelial cells (HUVEC). Pretreatment of cells with EGE attenuated TNF-α-induced increase in expression levels of cell adhesion molecules such as intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. Real time qRT-PCR also showed that EGE decreased the mRNA expression levels of ICAM-1, VCAM-1, E-selectin as well as macrophage chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8). In addition, EGE significantly inhibited TNF-α-induced increase in monocyte adhesion of HUVEC in a dose-dependent manner. Furthermore, EGE significantly inhibited TNF-α-induced intracellular reactive oxygen species (ROS) production and p65 NF-κB activation by preventing IκB-α phosphorylation. In conclusion, the present data suggest that EGE could suppress TNF-α-induced vascular inflammatory process via inhibition of oxidative stress and NF-κB activation in HUVEC.
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Goyal, Ravinder K., Maria Augusta Schmidt i Michael F. Hynes. "Molecular Biology in the Improvement of Biological Nitrogen Fixation by Rhizobia and Extending the Scope to Cereals". Microorganisms 9, nr 1 (7.01.2021): 125. http://dx.doi.org/10.3390/microorganisms9010125.
Pełny tekst źródłaStreszczenie:
The contribution of biological nitrogen fixation to the total N requirement of food and feed crops diminished in importance with the advent of synthetic N fertilizers, which fueled the “green revolution”. Despite being environmentally unfriendly, the synthetic versions gained prominence primarily due to their low cost, and the fact that most important staple crops never evolved symbiotic associations with bacteria. In the recent past, advances in our knowledge of symbiosis and nitrogen fixation and the development and application of recombinant DNA technology have created opportunities that could help increase the share of symbiotically-driven nitrogen in global consumption. With the availability of molecular biology tools, rapid improvements in symbiotic characteristics of rhizobial strains became possible. Further, the technology allowed probing the possibility of establishing a symbiotic dialogue between rhizobia and cereals. Because the evolutionary process did not forge a symbiotic relationship with the latter, the potential of molecular manipulations has been tested to incorporate a functional mechanism of nitrogen reduction independent of microbes. In this review, we discuss various strategies applied to improve rhizobial strains for higher nitrogen fixation efficiency, more competitiveness and enhanced fitness under unfavorable environments. The challenges and progress made towards nitrogen self-sufficiency of cereals are also reviewed. An approach to integrate the genetically modified elite rhizobia strains in crop production systems is highlighted.
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Goyal, Ravinder K., Maria Augusta Schmidt i Michael F. Hynes. "Molecular Biology in the Improvement of Biological Nitrogen Fixation by Rhizobia and Extending the Scope to Cereals". Microorganisms 9, nr 1 (7.01.2021): 125. http://dx.doi.org/10.3390/microorganisms9010125.
Pełny tekst źródłaStreszczenie:
The contribution of biological nitrogen fixation to the total N requirement of food and feed crops diminished in importance with the advent of synthetic N fertilizers, which fueled the “green revolution”. Despite being environmentally unfriendly, the synthetic versions gained prominence primarily due to their low cost, and the fact that most important staple crops never evolved symbiotic associations with bacteria. In the recent past, advances in our knowledge of symbiosis and nitrogen fixation and the development and application of recombinant DNA technology have created opportunities that could help increase the share of symbiotically-driven nitrogen in global consumption. With the availability of molecular biology tools, rapid improvements in symbiotic characteristics of rhizobial strains became possible. Further, the technology allowed probing the possibility of establishing a symbiotic dialogue between rhizobia and cereals. Because the evolutionary process did not forge a symbiotic relationship with the latter, the potential of molecular manipulations has been tested to incorporate a functional mechanism of nitrogen reduction independent of microbes. In this review, we discuss various strategies applied to improve rhizobial strains for higher nitrogen fixation efficiency, more competitiveness and enhanced fitness under unfavorable environments. The challenges and progress made towards nitrogen self-sufficiency of cereals are also reviewed. An approach to integrate the genetically modified elite rhizobia strains in crop production systems is highlighted.
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Baca, Bart J., Thomas E. Lankford i Erich R. Gundlach. "RECOVERY OF BRITTANY COASTAL MARSHES IN THE EIGHT YEARS FOLLOWING THE AMOCO CADIZ INCIDENT". International Oil Spill Conference Proceedings 1987, nr 1 (1.04.1987): 459–64. http://dx.doi.org/10.7901/2169-3358-1987-1-459.
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ABSTRACT The salt marshes on the Brittany coast of France have undergone a number of changes and have been influenced by man-made and natural factors since the Amoco Cadiz spill of March 1978. This work catalogs the ecological changes which have occurred over the past eight years and presents original data on the present state of these marshes. The recovery of Brittany coastal marshes began following cleanup operations which were often damaging to marsh and marsh substrate. The physical and toxicological properties of the oil also were damaging in the short term, especially to annual species. Natural recovery began primarily by invasion of exposed areas with annuals and rhizome spreading of perennials. Within four years, an almost logarithmic recruitment process was begun by annuals followed by perennials. Pioneer and opportunistic species increased, facilitated by partially vegetated substrates available for seed and seedling retention and by increased seed and rhizome production. Man-induced restoration was also important and was done largely by planting wild or cultured stock. The final stage of marsh recovery, as existing today, is the emergence of perennial species of high and low marsh at elevations and tidal exposures typical for their growth. These successional changes in a marsh following a major oil spill (and various other man-made impacts) provide an understanding of the complex processes involved in marsh recovery. This understanding allows the formulation of planning guidelines to predict the long-term impacts of future incidents and to make proper recommendations for cleanup and restoration to aid the recovery process.
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Hastwell, April H., Peter M. Gresshoff i Brett J. Ferguson. "The structure and activity of nodulation-suppressing CLE peptide hormones of legumes". Functional Plant Biology 42, nr 3 (2015): 229. http://dx.doi.org/10.1071/fp14222.
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Legumes form a highly-regulated symbiotic relationship with specific soil bacteria known as rhizobia. This interaction results in the de novo formation of root organs called nodules, in which the rhizobia fix atmospheric di-nitrogen (N2) for the plant. Molecular mechanisms that regulate the nodulation process include the systemic ‘autoregulation of nodulation’ and the local nitrogen-regulation of nodulation pathways. Both pathways are mediated by novel peptide hormones called CLAVATA/ESR-related (CLE) peptides that act to suppress nodulation via negative feedback loops. The mature peptides are 12–13 amino acids in length and are post-translationally modified from the C-terminus of tripartite-domain prepropeptides. Structural redundancy between the prepropeptides exists; however, variations in external stimuli, timing of expression, tissue specificity and presence or absence of key functional domains enables them to act in a specific manner. To date, nodulation-regulating CLE peptides have been identified in Glycine max (L.) Merr., Medicago truncatula Gaertn., Lotus japonicus (Regel) K.Larsen and Phaseolus vulgaris L. One of the L. japonicus peptides, called LjCLE-RS2, has been structurally characterised and found to be an arabinosylated glycopeptide. All of the known nodulation CLE peptides act via an orthologous leucine rich repeat (LRR) receptor kinase. Perception of the peptide results in the production of a novel, unidentified inhibitor signal that acts to suppress further nodulation events. Here, we contrast and compare the various nodulation-suppressing CLE peptides of legumes.
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Swapna B., Chandrasekhar K B, Madhuri D. i Sumathi G. "Biological Synthesis and Characterisation of Silver Nanoparticles of Zingiber officinalis and Evaluation of its Biological Activity". International Journal of Research in Pharmaceutical Sciences 13, nr 4 (3.12.2022): 396–402. http://dx.doi.org/10.26452/ijrps.v13i4.3833.
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Ginger (Zingiber officinale) belongs to Zingiberaceae family is one of the famous spices all over the world. It is a perennial creeping plant with long leaves, yellow green flowers and thick tuberous rhizome. Silver nanoparticles’ potential uses in Green Chemistry have received attention. The current study focuses on the rapid biological production of silver nanoparticles using different plant materials and characterizations using UV-visible spectrophotometry, IR, SEM, and HPLC investigations. Within 15 minutes of adding sodium carbonate, an aqueous extract of dried Zingiber officinalis rhizome reduces silver nitrate. No further reduction and stabilizing chemicals are required for the entire process, showing a green synthesis. Escherichia coli and Staphylococcus aureus use biosynthesized “Zinger-AgNps” as a competent antibacterial agent. Zinger-AgNps were evaluated as its catalytic capability to reduce the model pollutant methylene blue. Both of them are displayed 2, 2-diphenyl-1-picrylhydrazyl-specific free radical scavenging activity (DPPH). Silver biological material nanoparticles are created by utilizing less hazardous and nontoxic reduction agents, such as ascorbic acid and sodium citrate. The antioxidant and lipid peroxidation inhibition properties of ginger prevent peroxidative damage, indicating the benefits of ginger in the prevention of microbial food spoilage, free-radical-induced damage and rancidity. The sodium citrate aggregation for silver nanoparticles, firm surface contact, and synthesized silver nanoparticles are used to study antibacterial efficacy and antioxidant activity.
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Mozumder, Atifa Begum, Kakoli Chanda, Ringhoilal Chorei i Himanshu Kishore Prasad. "An Evaluation of Aluminum Tolerant Pseudomonas aeruginosa A7 for In Vivo Suppression of Fusarium Wilt of Chickpea Caused by Fusarium oxysporum f. sp. ciceris and Growth Promotion of Chickpea". Microorganisms 10, nr 3 (5.03.2022): 568. http://dx.doi.org/10.3390/microorganisms10030568.
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Chickpea wilt, caused by Fusarium oxysporum f. sp. ciceris, is a disease that decreases chickpea productivity and quality and can reduce its yield by as much as 15%. A newly isolated, moss rhizoid-associated Pseudomonas aeruginosa strain A7, demonstrated strong inhibition of Fusarium oxysporum f. sp. ciceris growth. An in vitro antimicrobial assay revealed A7 to suppress the growth of several fungal and bacterial plant pathogens by secreting secondary metabolites and by producing volatile compounds. In an in vivo pot experiment with Fusarium wilt infection in chickpea, the antagonist A7 exhibited a disease reduction by 77 ± 1.5%, and significantly reduced the disease incidence and severity indexes. Furthermore, A7 promoted chickpea growth in terms of root and shoot length and dry biomass during pot assay. The strain exhibited several traits associated with plant growth promotion, extracellular enzymatic production, and stress tolerance. Under aluminum stress conditions, in vitro growth of chickpea plants by A7 resulted in a significant increase in root length and plant biomass production. Additionally, hallmark genes for antibiotics production were identified in A7. The methanol extract of strain A7 demonstrated antimicrobial activity, leading to the identification of various antimicrobial compounds based on retention time and molecular weight. These findings strongly suggest that the strain’s significant biocontrol potential and plant growth enhancement could be a potential environmentally friendly process in agricultural crop production.
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Xiang, Quanju, Jie Wang, Peng Qin, Bilal Adil, Kaiwei Xu, Yunfu Gu, Xiumei Yu i in. "Effect of common bean seed exudates on growth, lipopolysaccharide production, and lipopolysaccharide transport gene expression of Rhizobium anhuiense". Canadian Journal of Microbiology 66, nr 3 (marzec 2020): 186–93. http://dx.doi.org/10.1139/cjm-2019-0413.
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Lipopolysaccharide (LPS) is essential for successful nodulation during the symbiosis of rhizobia and legumes. However, the detailed mechanism of the LPS in this process has not yet been clearly elucidated. In this study, the effects of common bean seed exudates on the growth, lipopolysaccharide production, and lipopolysaccharide transport genes expression (lpt) of Rhizobium anhuiense were investigated. Rhizobium anhuiense exposed to exudates showed changes in LPS electrophoretic profiles and content, whereby the LPS band was wider and the LPS content was higher in R. anhuiense treated with seed exudates. Exudates enhanced cell growth of R. anhuiense in a concentration-dependent manner; R. anhuiense exposed to higher doses of the exudate showed faster growth. Seven lpt genes of R. anhuiense were amplified and sequenced. Sequences of six lpt genes, except for lptE, were the same as those found in previously analyzed R. anhuiense strains, while lptE shared low sequence similarity with other strains. Exposure to the exudates strongly stimulated the expression of all lpt genes. Approximately 6.7- (lptG) to 301-fold (lptE) increases in the transcriptional levels were observed after only 15 min of exposure to exudates. These results indicate that seed exudates affect the LPS by making the cell wall structure more conducive to symbiotic nodulation.
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Pollard, PC, i K. Kogure. "Bacterial decomposition of detritus in a tropical seagrass (Syringodium isoetifolium) ecosystem, measured with (Methyl- super-3H)thymidine". Marine and Freshwater Research 44, nr 1 (1993): 155. http://dx.doi.org/10.1071/mf9930155.
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The bacterial decomposition of detritus was measured in a tropical seagrass meadow (Syringodium isoetifolium) off Dravuni Island, Fiji, and compared with the seagrass and algal productivity. Our estimates of bacterial decomposition of organic matter was based on the rate at which the bacteria divided, and this was measured by the rate at which [methyl-3H]thymidine was incorporated into the bacterial DNA. Bacterial activity was greatest in the top 1 cm of the seagrass sediments. The number of bacteria, their specific growth rate, and their productivity were 6.3 � 0.3 × 109 cells cm-3 , 0.04� 0.005 h-1, and 0.671 g C day-1 m-2 (depth-integrated over 30 cm), respectively. At the sediment surface, bacterial activity coincided with the daily light intensities during the day. Benthic microalgal production seemd to be coupled to the heterotrophic bacterial activity. However, the amount of organic carbon passing through the bacterial decomposition process was small compared with the total autotrophic production. The net bacterial productivity was only between 4 and 6% of that of microalgae and 6% of that of the seagrass. The bacteria appeared to play a minor role in the transfer of organic carbon between the primary producers and the higher trophic groups. Much of the microalgal production could have been directly consumed by the benthic infauna, whereas the seagrass production may have been translocated, via the seagrass roots and rhizomes, to other parts of the plant and/or converted into more refractory or storage compounds.
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Kereszt, Attila, Ernő Kiss, Bradley L. Reuhs, Russell W. Carlson, Ádám Kondorosi i Péter Putnoky. "Novel rkp Gene Clusters ofSinorhizobium meliloti Involved in Capsular Polysaccharide Production and Invasion of the Symbiotic Nodule: the rkpKGene Encodes a UDP-Glucose Dehydrogenase". Journal of Bacteriology 180, nr 20 (15.10.1998): 5426–31. http://dx.doi.org/10.1128/jb.180.20.5426-5431.1998.
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ABSTRACT The production of exopolysaccharide (EPS) was shown to be required for the infection process by rhizobia that induce the formation of indeterminate nodules on the roots of leguminous host plants. InSinorhizobium meliloti (also known as Rhizobium meliloti) Rm41, a capsular polysaccharide (KPS) analogous to the group II K antigens of Escherichia coli can replace EPS during symbiotic nodule development and serve as an attachment site for the strain-specific bacteriophage φ16-3. The rkpA to -J genes in the chromosomal rkp-1 region code for proteins that are involved in the synthesis, modification, and transfer of an as-yet-unknown lipophilic molecule which might function as a specific lipid carrier during KPS biosynthesis. Here we report that with a phage φ16-3-resistant population obtained after random Tn5 mutagenesis, we have identified novel mutants impaired in KPS production by genetic complementation and biochemical studies. The mutations represent two novel loci, designated therkp-2 and rkp-3 regions, which are required for the synthesis of rhizobial KPS. The rkp-2 region harbors two open reading frames (ORFs) organized in monocistronic transcription units. Although both genes are required for normal lipopolysaccharide production, only the second one, designated rkpK, is involved in the synthesis of KPS. We have demonstrated that RkpK possesses UDP-glucose dehydrogenase activity, while the protein product of ORF1 might function as a UDP-glucuronic acid epimerase.
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Mustafa, Iswaibah, Nyuk Ling Chin, Sharida Fakurazi i Arulselvan Palanisamy. "Comparison of Phytochemicals, Antioxidant and Anti-Inflammatory Properties of Sun-, Oven- and Freeze-Dried Ginger Extracts". Foods 8, nr 10 (6.10.2019): 456. http://dx.doi.org/10.3390/foods8100456.
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The effects of different drying methods, including sun-, oven-, and freeze-drying on the changes in the antioxidant and anti-inflammatory activities of ginger (Zingiber officinale var. Rubra) rhizome were studied. Sun-, oven-, and freeze-dried ginger showed a significant (p < 0.05) increase in phenolic content by 1.79, 1.53, and 1.91-fold; flavonoid content increased by 6.06, 5.27, and 4.90-fold; FRAP increased by 3.95, 3.51, and 3.15-fold; ABTS•+ scavenging activity increased by 2.07, 1.72, and 1.61-fold; and DPPH• inhibition increased by 78%, 58%, and 56%, respectively. Dried ginger also exhibited better inhibitory effects on the lipopolysaccharides-induced nitric oxide production in murine macrophage RAW 264.7. The drying process demonstrated a positive effect on the bioactivities of ginger. The sun-dried ginger exhibited the most potent antioxidant properties with the best enhanced anti-inflammatory activity followed by the oven-dried ginger and lastly, the freeze-dried ginger.
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Reents, Svenja, Peter Mueller, Hao Tang, Kai Jensen i Stefanie Nolte. "Plant genotype determines biomass response to flooding frequency in tidal wetlands". Biogeosciences 18, nr 2 (18.01.2021): 403–11. http://dx.doi.org/10.5194/bg-18-403-2021.
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Abstract. The persistence of tidal wetland ecosystems like salt marshes is threatened by human interventions and climate change. In particular, the threat of accelerated sea level rise (SLR) has increasingly gained the attention of the scientific community recently. However, studies investigating the effect of SLR on plants and vertical marsh accretion are usually restricted to the species or community level and do not consider phenotypic plasticity or genetic diversity. To investigate the response of genotypes within the same salt-marsh species to SLR, we used two known genotypes of Elymus athericus (Link) Kerguélen (low-marsh and high-marsh genotypes). In a factorial marsh organ experiment we exposed both genotypes to different flooding frequencies and quantified plant growth parameters. With increasing flooding frequency, the low-marsh genotype showed higher aboveground biomass production compared to the high-marsh genotype. Additionally, the low-marsh genotype generally formed longer rhizomes, shoots and leaves, regardless of flooding frequency. Belowground biomass of both genotypes decreased with increasing flooding frequency. We conclude that the low-marsh genotype is better adapted to higher flooding frequencies through its ability to allocate resources from below- to aboveground biomass. Given the strong control of plant biomass production on salt-marsh accretion, we argue that these findings yield important implications for our understanding of ecosystem resilience to SLR as well as plant species distribution in salt marshes.
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Benmoussa, Sabrine, Issam Nouairi, Imen Rajhi, Saber Rezgui, Khediri Manai, Wael Taamali, Zouhaier Abbes, Kais Zribi, Renaud Brouquisse i Haythem Mhadhbi. "Growth Performance and Nitrogen Fixing Efficiency of Faba Bean (Vicia faba L.) Genotypes in Symbiosis with Rhizobia under Combined Salinity and Hypoxia Stresses". Agronomy 12, nr 3 (28.02.2022): 606. http://dx.doi.org/10.3390/agronomy12030606.
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The present study was carried out in order to investigate the behaviour of six faba bean (Vicia faba Minor) genotypes (Saber 02, Locale, Baachar, Badii, Chourouk and Najeh) in response to salinity and flooding (hypoxia), either alone or combined, to identify tolerant genotypes and to select efficient faba bean-rhizobia symbiosis under salinity and/or hypoxia conditions. faba bean genotypes were cultivated in three agricultural soils with either low (160 µs/cm) or moderate (1850 µs/cm) salt content and submitted or not to a 30-day long flooding period. Growth parameters and photosynthetic performance were analyzed at the end of the flowering period. At harvest time, the Najeh genotype showed the highest dry mass production in both control and hypoxia conditions (7.90 and 6.75 g/plant, respectively), whereas Saber 02 showed the lowest (3.75 and 2.25 g/plant, respectively). Differences between genotypes were less marked in salinity or combined salinity/flooding conditions. Principal component analysis of the analyzed parameters revealed that the Najeh genotype presents the best growth and the lowest photosynthetic perturbation and lipid peroxidation levels, whether under control or hypoxic conditions, whereas Saber 02 and Locale genotypes were less productive. Ninety bacteria strains were isolated from Vicia faba root nodules. Of these, 47 strains were identified as rhizobia, and 20 were able to re-nodulate the host plant. After the characterization, identification and selection process, four strains were selected as the best faba bean symbiotic partners based on their symbiotic efficiency and salt tolerance behaviours. Our results suggest that faba bean tolerant genotypes in symbiosis with these strains could be useful in enhancing legume cultivation under saline and hypoxia field conditions.
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Lei, Zhang, Gu Jian-ping, Wei Shi-qing, Zhou Ze-yang, Zhang Chao i Yu Yongxiong. "Mechanism of acid tolerance in a rhizobium strain isolated from Pueraria lobata (Willd.) Ohwi". Canadian Journal of Microbiology 57, nr 6 (czerwiec 2011): 514–24. http://dx.doi.org/10.1139/w11-036.
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The Rhizobium sp. strain PR389 was isolated from the root nodules of Pueraria lobata (Willd.) Ohwi, which grows in acidic (pH 4.6) yellow soil of the Jinyun Mountains of Beibei, Chongqing, China. While rhizobia generally have a pH range of 6.5–7.5 for optimum growth, strain PR389 grew in a liquid yeast extract – mannitol agar medium at pH 4.6, as well as in a pH 4.1 soil suspension, suggesting acid tolerance in this specific strain of rhizobium . However, at pH 4.6, the lag phase before vigorous growth was 40 h compared with 4 h under neutral conditions (pH 7.0). For PR389, the generation time after the lag phase remained the same at different pH levels despite the different durations of the lag phase. Except in the pH 4.4 treatment, the pH of the culturing media increased from 4.6, 4.8, 5.0, and 5.5 to neutral and slightly alkaline after 70 h of culture. Chloramphenicol was added to determine if protein production was involved in the increasing pH process. Chloramphenicol significantly inhibited PR389 growth under acid stress but had little effect under neutral conditions. Proton flux measured during a short acid shock (pH 3.8) revealed that this strain has an intrinsic ability to prevent H+ from entering cells when compared with acid-sensitive rhizobia. We propose that the mechanism for acid tolerance in PR389 involves both intracellular and extracellular processes. When the extracellular pH is lower than pH 4.4, the cell membrane blocks hydrogen from entering the cell. When the pH exceeds 4.4, the rhizobium strain has the ability to raise the extracellular pH, thereby, potentially decreasing the toxicity of aluminum in acid soil.
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Terpolilli, Jason J., Shyam K. Masakapalli, Ramakrishnan Karunakaran, Isabel U. C. Webb, Rob Green, Nicholas J. Watmough, Nicholas J. Kruger, R. George Ratcliffe i Philip S. Poole. "Lipogenesis and Redox Balance in Nitrogen-Fixing Pea Bacteroids". Journal of Bacteriology 198, nr 20 (8.08.2016): 2864–75. http://dx.doi.org/10.1128/jb.00451-16.
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ABSTRACTWithin legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the tricarboxylic acid (TCA) cycle to generate NAD(P)H for reduction of N2. Metabolic flux analysis of laboratory-grownRhizobium leguminosarumshowed that the flux from [13C]succinate was consistent with respiration of an obligate aerobe growing on a TCA cycle intermediate as the sole carbon source. However, the instability of fragile pea bacteroids prevented their steady-state labeling under N2-fixing conditions. Therefore, comparative metabolomic profiling was used to compare free-livingR. leguminosarumwith pea bacteroids. While the TCA cycle was shown to be essential for maximal rates of N2fixation, levels of pyruvate (5.5-fold reduced), acetyl coenzyme A (acetyl-CoA; 50-fold reduced), free coenzyme A (33-fold reduced), and citrate (4.5-fold reduced) were much lower in bacteroids. Instead of completely oxidizing acetyl-CoA, pea bacteroids channel it into both lipid and the lipid-like polymer poly-β-hydroxybutyrate (PHB), the latter via a type III PHB synthase that is active only in bacteroids. Lipogenesis may be a fundamental requirement of the redox poise of electron donation to N2in all legume nodules. Direct reduction by NAD(P)H of the likely electron donors for nitrogenase, such as ferredoxin, is inconsistent with their redox potentials. Instead, bacteroids must balance the production of NAD(P)H from oxidation of acetyl-CoA in the TCA cycle with its storage in PHB and lipids.IMPORTANCEBiological nitrogen fixation by symbiotic bacteria (rhizobia) in legume root nodules is an energy-expensive process. Within legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the TCA cycle to generate NAD(P)H for reduction of N2. However, direct reduction of the likely electron donors for nitrogenase, such as ferredoxin, is inconsistent with their redox potentials. Instead, bacteroids must balance oxidation of plant-derived dicarboxylates in the TCA cycle with lipid synthesis. Pea bacteroids channel acetyl-CoA into both lipid and the lipid-like polymer poly-β-hydroxybutyrate, the latter via a type II PHB synthase. Lipogenesis is likely to be a fundamental requirement of the redox poise of electron donation to N2in all legume nodules.