Статті в журналах: "Biogenic–surfactants"

1

Karpenko, I. V., G. G. Midyana, E. V. Karpenko, R. G. Makitra, and E. Ya Pal’chikova. "Extraction of biogenic rhamnolipid surfactants." Russian Journal of General Chemistry 84, no. 7 (July 2014): 1367–70. http://dx.doi.org/10.1134/s1070363214070202.

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Карпенко, Ілона Василівна, Галина Григорівна Мідяна, and Олена Володимирівна Карпенко. "Biogenic Rhamnolipid Surfactants in Complex Plant Growth Regulators." Research Bulletin of the National Technical University of Ukraine "Kyiv Polytechnic Institute", no. 3 (June 30, 2016): 36. http://dx.doi.org/10.20535/1810-0546.2016.3.65576.

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Karpenko, E. V., T. Ya Pokin’broda, R. G. Makitra, and E. Ya Pal’chikova. "Optimal methods of isolation of biogenic ramnolipid surfactants." Russian Journal of General Chemistry 79, no. 12 (December 2009): 2637–40. http://dx.doi.org/10.1134/s1070363209120135.

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4

Pokhmurs’kyi, V. І., О. V. Karpenko, І. М. Zin’, М. B. Tymus’, and H. H. Veselivs’ka. "Inhibiting Action of Biogenic Surfactants in Corrosive Media." Materials Science 50, no. 3 (November 2014): 448–53. http://dx.doi.org/10.1007/s11003-014-9741-4.

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5

Poremba, K., W. Gunkel, S. Lang, and F. Wagner. "Toxicity testing of synthetic and biogenic surfactants on marine microorganisms." Environmental Toxicology & Water Quality 6, no. 2 (May 1991): 157–63. http://dx.doi.org/10.1002/tox.2530060205.

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6

Santos, Vanessa Santana Vieira, Edgar Silveira, and Boscolli Barbosa Pereira. "Ecotoxicological assessment of synthetic and biogenic surfactants using freshwater cladoceran species." Chemosphere 221 (April 2019): 519–25. http://dx.doi.org/10.1016/j.chemosphere.2019.01.077.

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7

Brüggemann, Martin, Nathalie Hayeck, Chloé Bonnineau, Stéphane Pesce, Peter A. Alpert, Sébastien Perrier, Christoph Zuth, Thorsten Hoffmann, Jianmin Chen, and Christian George. "Interfacial photochemistry of biogenic surfactants: a major source of abiotic volatile organic compounds." Faraday Discussions 200 (2017): 59–74. http://dx.doi.org/10.1039/c7fd00022g.

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Films of biogenic compounds exposed to the atmosphere are ubiquitously found on the surfaces of cloud droplets, aerosol particles, buildings, plants, soils and the ocean. These air/water interfaces host countless amphiphilic compounds concentrated there with respect to in bulk water, leading to a unique chemical environment. Here, photochemical processes at the air/water interface of biofilm-containing solutions were studied, demonstrating abiotic VOC production from authentic biogenic surfactants under ambient conditions. Using a combination of online-APCI-HRMS and PTR-ToF-MS, unsaturated and functionalized VOCs were identified and quantified, giving emission fluxes comparable to previous field and laboratory observations. Interestingly, VOC fluxes increased with the decay of microbial cells in the samples, indicating that cell lysis due to cell death was the main source for surfactants and VOC production. In particular, irradiation of samples containing solely biofilm cells without matrix components exhibited the strongest VOC production upon irradiation. In agreement with previous studies, LC-MS measurements of the liquid phase suggested the presence of fatty acids and known photosensitizers, possibly inducing the observed VOC productionviaperoxy radical chemistry. Up to now, such VOC emissions were directly accounted to high biological activity in surface waters. However, the results obtained suggest that abiotic photochemistry can lead to similar emissions into the atmosphere, especially in less biologically-active regions. Furthermore, chamber experiments suggest that oxidation (O₃/OH radicals) of the photochemically-produced VOCs leads to aerosol formation and growth, possibly affecting atmospheric chemistry and climate-related processes, such as cloud formation or the Earth’s radiation budget.

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8

Kenzhegaliyev, A., D. K. Kulbatyrov, A. Sh Kanbetov, A. K. Shakhmanova, and A. A. Abilgaziyeva. "Study of the State of Surface Waters of the Northeast Caspian Sea During Development of Oil Fields." E3S Web of Conferences 288 (2021): 01063. http://dx.doi.org/10.1051/e3sconf/202128801063.

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The relevance of the research is due to the fact that the Kashagan field has resumed oil and gas production, and up to this date more than 40 million tons of oil have been produced. In this regard, the study of the state of pollution of surface waters and its dynamics is relevant. This article is aimed at detecting the state of contamination with biogenic elements, oil products, phenol, synthetic surfactants and heavy metals. The leading approach to the study of this problem is State Standard 17.1.5.04-81; The seawater sampling procedure is carried out in accordance with ISO 5667-9: 1992 and ISO 5667-2. The article presents the results of research conducted in 2019 and the dynamics of pollution with pollutants in the area of the Kashagan, Kairan and Aktoty fields in the licensed territory. At the Kashagan field, samples were taken from 14 observation stations for the study. The fields of Kairan and Aktoty are currently preserved. In this regard, 2 observation stations were studied at each of these deposits and the results were compared with the results of the previous year. Based on the data obtained, it was revealed that biogenic elements remained at the same level and below the maximum permissible concentration for the entire study period. Comparison with last years’ studies shows that in 2019, the concentration of biogenic elements was lower than 2018. The content of oil products and synthetic surfactants for the study period was higher than in 2018, but lower than the MPC for the fisheries reservoir, and the phenol content was at the level of 2018 and exceeds the maximum permissible concentration by 3 times. Heavy metals for the entire study period were at the same level, with the exception of copper and iron, the concentration of which is higher than in 2018, but less than the MPC. The materials of the article are of practical value for scientists engaged in the study of the state of the inland seas, undergraduates, doctoral students.

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9

Podolska, V. I., O. Yu Voitenko, N. I. Gryshchenko, O. G. Savkin, and L. M. Yakubenko. "The influence of surfactants on biogenic synthesis of silver nanoparticles in lactic acid bacteria." Himia, Fizika ta Tehnologia Poverhni 11, no. 2 (June 30, 2020): 201–14. http://dx.doi.org/10.15407/hftp11.02.201.

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10

Dong, Qun, Hui Lan Su, Di Zhang, Wei Cao, and Jie Han. "In Situ Synthesis of Hierarchical Nanocomposites Utilizing Redox-Active Biofibers by a Novel Biogenic Technique." Materials Science Forum 561-565 (October 2007): 787–90. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.787.

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Biogenic technique for the synthesis of composites with nanopatterns is evolving into an important branch of nanobiotechnology and materials science. In this work, the biomaterials eggshell membrane fibers (ESMF) and silk fibroin fibers (SFF) were infused into palladium chloride and silver nitrate solution at room temperature to actualize the extracellular nucleation of noble metal nanocrystallites and in situ assembly into composites with hierarchical nanostructures on the biofibers. The present biofibers not only served as the reacting substrates but also functioned as the surfactants, so that small-sized but well-crystallized nanocrystallites could be organized into subtle hierarchy to form inorganic-organic nanocomposites under the direction of the biomacromolecules.

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11

Rani, N., and K. Saini. "Biogenic Metal and Metal Oxides Nanoparticles as Anticancer Agent: A Review." IOP Conference Series: Materials Science and Engineering 1225, no. 1 (February 1, 2022): 012043. http://dx.doi.org/10.1088/1757-899x/1225/1/012043.

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Abstract Herein this review we have summarized a number of cytotoxic studies which have been done using various biosynthesized metal nanoparticles (MNPs) and metal oxide nanoparticles (MONPs) on different cancer cell lines. Plants can serve as a good candidate to provide natural surfactants for the green approach in the preparation of nanoparticles. Numerous bio-molecules are present in the plants. Also, numerous plant extract-based MNPs and MONPs have been synthesized and used in several fields of applications particularly in biomedicine. This property can be attributed because of their low cost, biocompatibility and favourable to the environment. In the past few years, the utilisation of these biogenic nanoparticles has in-creased tremendously particularly in cancer therapy. These biogenic nanoparticles considered as an excellent tool for cancer diagnosis and drug delivery at the tumour site preferentially. By utilising the unique properties of nanoparticles and antioxidant and antitumor nature of plants, these biosynthesised nanoparticles selectively destroy the tumour cells and do not harm the normal healthy cells. In this review, we have compiled the most significant results obtained by the biosynthesized MNPs and MONPs like silver (Ag), gold (Au), Fe2O3/Fe3O4, ZnO, and CuO respectively.

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12

Lupak, M., M. Khokhla, G. Hachkova, O. Shulga, N. Sheglova, R. Vildanova, A. Zyn, and N. Sybirna. "Application of biogenic surfactants for stabilization on alkaloid-free fraction isolated from Galega officinalis extract." Studia Biologica 9, no. 1 (2015): 25–36. http://dx.doi.org/10.30970/sbi.0901.397.

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13

Babienko, V. V., I. V. Sakharova, and L. I. Danilchenko. "THE ACID-BASE PROCESSES' CHANGES IN THE BODY OF WHITE RATS UNDER THE INFLUENCE OF NITROGEN-CONTAINING SURFACE-ACTIVE MATERIAL." Medical Science of Ukraine (MSU) 16, no. 3 (September 30, 2020): 14–19. http://dx.doi.org/10.32345/2664-4738.3.2020.3.

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Relevance. Everyday contact of the population with surfactants (SAS) in drinking water poses the problem of timely and prompt substantiation of pre-nosological highly sensitive indicators of early manifestations of biological activity of detergents and operational control over the health of the population and the environment. But today the mechanisms of biotransformation, toxicodynamics, toxicokinetics, and metabolic processes that underlie the formation of structural and metabolic disorders when exposed to a surfactant, taking into account possible long-term effects, have not yet been fully elucidated. Objective: to investigate the effect of nitrogen-containing surfactants on redox processes in the body of experimental animals. Materials and methods. The experiments were carried out on 620, and acute experiments on 128 white rats (weight 180-220 g). We used four ionic nitrogen-containing surfactants with specified technical and physicochemical characteristics: FOM 9, FOM 9-4, FOM 9-12, and FOM 9-20. Doses were chosen so as to determine the lethal effect in the lethal dose (LD) range from 0 to 100. The LD50 was calculated. The substances were introduced into the stomach in pure form using a metal probe. The animals were observed for up to 15 days. The time of death of the animals and the total amount of the introduced substance was recorded. The animals were subjected to postmortem examination. Redox processes were qualitatively assessed by the activity of enzymes: cholinesterase, cerulose plasmin, lactate dehydrogenase, malate dehydrogenase, succinate dehydrogenase, peroxidase, catalase, cytochrome oxidase, by the content of SH-groups in the blood, by the concentration of biogenic monoamines. Results. Nitrogen-containing surfactants caused a change in peroxidase activity both upwards and downwards. In all cases, 1/1000 LD50 was inactive. On the 15th day of the experiment, neonol FOM 9-12 reduced the activity of the enzyme, and other substances did not affect it. By the end of the subacute experiment, neonol FOM 9-4 and neonol FOM 9-12 were reduced, and neonol FOM 9-20 increased peroxidase activity. A similar effect was on the activity of catalase: in all groups, except 1/1000 LD50, on day 30 there was a decrease in its activity. Cholinesterase activity increased. For the content of SH-groups in the blood on the 15th day, there was a tendency to decrease, which turned into significant differences on the 30th day in 1/10 LD50. The effect of 1/100 and 1/1000 LD50 did not violate the content of SH-blood groups. A similar effect was on the content of glutathione in the blood. In a subacute experiment, in groups, 1/10 and 1/100 LD50, the content of norepinephrine, tryptophan, serotonin in the liver increased and DOPA and dopamine decreased. The dynamics of adrenaline did not change. The content of dopamine and norepinephrine increased to a lesser extent in the brain; DOPA and adrenaline did not differ from the control; tryptophan increased only under the influence of FOM-9. 1/1000 LD50 did not affect the dynamics of the content of biogenic monoamines. The tested drugs have a similar effect on the body. Conclusions. A more toxic substance in a subacute experiment is FOM-9. The severity of violations in the dynamics of monitoring the activity of enzymes has a close dose-dependence. The effective dose is set at 1/10, the threshold – 1/100, and the inactive – 1/1000 LD50. Common features of the biological action of nitrogen-containing surfactants are the violation of redox processes, bioenergy, oxidative phosphorylation, which under appropriate conditions lead to the pathology of vital organs, functions, and systems of the body.

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Shevchyk-Kostiuk, Lesya, Olga Romaniuk, and Andriy Banya. "Improving the efficiency of phytoremediation technologies of oil-contaminated soils with the participation of natural sorbents-meliorants." Scientific Horizons 23, no. 10 (October 28, 2020): 7–16. http://dx.doi.org/10.48077/scihor.23(10).2020.7-16.

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Phytremediation is considered to be a promising and environmentally friendly way to restore oil-contaminated soils. However, the multicomponent nature of oil pollution, its low bioavailability, high stability, hydrophobicity, and toxicity require a comprehensive approach to its implementation. The purpose of the study is to investigate the influence of different types of sorbents-meliorants and their complexes with remediation agents on improvement of the efficiency of phytoremediation technologies of oil-contaminated soils. The study established that the most effective plants for phytoremediation of oil-contaminated soils are Vicia faba var. Minor, Pisum sativum L., Avena sativa L., which are the least exposed to toxic effects of oil among the studied crops, and better adapt to the conditions of oil-contaminated soils. The influence of sorbent-meliorants such as glauconite, zeolite, sawdust, and sunflower husk on the process of phytoremediation of oil-contaminated soils (oil content 5%) was studied. It was proven that sunflower husk is the most promising and available agent for accelerating phytoremediation. The study examined the individual and combined influence of mineral fertilisers, biogenic surfactants of microbial origin, and humates on the growth of Avena sativa plants under conditions of oil pollution, as well as on the process of soil restoration. The best results are obtained by application of the above agents in combination with sunflower husk. This complex (sunflower husk + mineral fertilizers + surfactants of microbial origin / humates) has a positive effect on Avena sativa plants – reduces the rate of oxidative stress, which indicates an improvement in the adaptability of plants to oil-contaminated soil; growth parameters increase; plant biomass accumulation; the total content of chlorophyll a+b increases; and there is an improvement in soil properties by reducing the oil content in soil, reducing phytotoxicity, increasing dehydrogenase activity

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Samadi, Nasrin, Neda Abadian, Reza Ahmadkhaniha, Farzaneh Amini, Dina Dalili, Noushin Rastkari, Eliyeh Safaripour, and Farzaneh Aziz Mohseni. "Structural characterization and surface activities of biogenic rhamnolipid surfactants from Pseudomonas aeruginosa isolate MN1 and synergistic effects against methicillin-resistant Staphylococcus aureus." Folia Microbiologica 57, no. 6 (May 29, 2012): 501–8. http://dx.doi.org/10.1007/s12223-012-0164-z.

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Poremba, K. "Influence of synthetic and biogenic surfactants on the toxicity of water-soluble fractions of hydrocarbons in sea water determined with the bioluminescence inhibition test." Environmental Pollution 80, no. 1 (1993): 25–29. http://dx.doi.org/10.1016/0269-7491(93)90005-9.

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17

Utkina, K., A. Garbuz, and M. Kulyk. "SURFACE WATER QUALITY IN KHARKIV RECREATIONAL AREAS: 2006-2020." Integrated Technologies and Energy Saving, no. 4 (December 30, 2021): 84–93. http://dx.doi.org/10.20998/2078-5364.2021.4.09.

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The aim of the paper is to assess dynamics of water quality in four main recreational areas in Kharkiv and to develop recommendations for water quality improvement. Methods. Field and laboratory methods and analytical data processing. Results. The paper presents analysis of dynamics in water quality for four main recreational areas located in Kharkiv: Zhuravlevskiy Hydropark, Oleksiivskiy Lugopark, Udyanskiy Hydropark and Osnovyanske Lake. Period of study: 2006-2020, time: May-June and August-September. Average data are presented. Samples were analysed at certified Laboratory of Analytical Chemical Research of the Karazin Institute of Environmental Sciences. Laboratory data were compared with national UA standards and European ones. Conclusions were made for the following key parameters: dissolved oxygen and BOD5, total mineralization, biogenic substances content, oil products and surfactants, toxic heavy metals content. There is no specific dynamics on the pollution level. Conclusions. The following recommendations for improvement of water quality were developed: (i) to preform regular monitoring of water quality; (ii) to introduce regular and systematic control by one local authority; (iii) to improve infrastructure of recreational areas; (iv) to introduce regular cleaning of the recreational areas; (v) to install bio-WC; (vi) to install additional waste containers (preferably with separate waste collection); (vii) plant trees for better isolation from highways; (viii) to improve level of water treatment on WWTP; (ix) to create nature protected areas along rivers

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Hashemi, Zahra, Mohammad Ali Ebrahimzadeh, Pourya Biparva, Sobhan Mortazavi-Derazkola, Hamid Reza Goli, Fereshteh Sadeghian, Mostafa Kardan, and Alireza Rafiei. "Biogenic Silver and Zero-Valent Iron Nanoparticles by Feijoa: Biosynthesis, Characterization, Cytotoxic, Antibacterial and Antioxidant Activities." Anti-Cancer Agents in Medicinal Chemistry 20, no. 14 (October 14, 2020): 1673–87. http://dx.doi.org/10.2174/1871520620666200619165910.

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Background: and Purpose: Green nanotechnology is an interesting method for the synthesis of functional nanoparticles. Because of their wide application, they have set up great attention in recent years. Objective: The present research examines the green synthesis of Ag and zero-valent iron nanoparticles (AgNPs, ZVINPs) by Feijoa sellowiana fruit extract. In this synthesis, no stabilizers or surfactants were applied. Methods: Eco-friendly synthesis of Iron and biogenic synthesis of Ag nanoparticles were accomplished by controlling critical parameters such as concentration, incubation period and temperature. Scanning Electron Microscopy (SEM), Transmission Electron Microscope (TEM), Energy-Dispersive X-ray Spectroscopy (EDS), Fourier-Transform Infrared (FT-IR) spectroscopy, X-ray Diffraction analysis (XRD), Dynamic Light Scattering (DLS) and UV-Vis were applied to characterize NPs. The cytotoxicity of NPs was investigated in two cell lines, MCF-7 (breast cancer) and AGS (human gastric carcinoma). A high-performance liquid chromatography (HPLC) analysis was also performed for characterization of phenolic acids in the extract. Results: Both NPs displayed powerful anticancer activities against two tumor cell lines with little effect on BEAS-2B normal cells. Synthesized AgNPs and ZVINPs inhibited the growth of all selected bacteria. Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumonia, Staphylococcus aureus, Enterococcus faecalis, Acinetobacter baumannii and Escherichia coli have been studied in two stages. We initially examined the ATCCs followed by clinical strain isolation. Based on the results from resistant strains, we showed that nanoparticles were superior to conventional antibiotics. DPPH (diphenyl-1-picrylhydrazyl) free radical scavenging assay and iron chelating activity were used for the determination of antioxidant properties. Results showed a high antioxidant activity of scavenging free radicals for ZVINPs and powerful iron-chelating activity for AgNPs. Based on the HPLC data, catechin was the major phenolic compound in the extract. Conclusion: Our synthesized nanoparticles displayed potent cytotoxic, antibacterial and antioxidant activities.

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19

Linares, Rosa M., and Juan H. Ayala. "Effect of non-ionic surfactants as mobile phase additives on the fluorescence intensity of dansyl derivatives of biogenic amines in high-performance thin-layer chromatography." Analyst 123, no. 4 (1998): 725–29. http://dx.doi.org/10.1039/a708500a.

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20

Choi, Gee Hyeun, Joanna Ivy Irorita Fugaban, Clarizza May Dioso, Jorge Enrique Vazquez Bucheli, Wilhelm Heinrich Holzapfel, and Svetoslav Dimitrov Todorov. "Selection of Bacteriocinogenic Bacillus spp. from Traditional Fermented Korean Food Products with Additional Beneficial Properties." Fermentation 7, no. 4 (November 21, 2021): 271. http://dx.doi.org/10.3390/fermentation7040271.

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Two Bacillus spp. isolated from kimchi, Bacillus tequilensis ST816CD and Bacillus subtilis ST830CD, were characterized for their antimicrobial properties and safety. The proteinaceous nature of their inhibitory metabolites was confirmed after exposure to proteolytic enzymes, resulting in partial loss of the antimicrobial effect. This indicated that different non-proteinaceous antimicrobial substances may also be produced by these strains. This hypothesis was later confirmed when genes associated with the production of surfactants were detected in their DNA. The expressed antimicrobial metabolites were not affected by treatment at different temperatures and pH levels, including exposure to selected chemicals. Their strong adherence to susceptible pathogens was not significantly affected by different temperatures, chemicals, or pH values. Both Bacillus strains showed inhibitory activity against clinical and food-associated pathogens, including Listeria monocytogenes ATCC 15313, and some Staphylococcus species. Several genes associated with the production of antimicrobial metabolites were detected, but key virulence and beneficial genes were not present in these strains. Even though only B. tequilensis ST816CD displayed γ-hemolysin production, both selected strains were found to produce gelatinase and biogenic amines, which are considered as either potential virulence- or health-related factors. Moreover, the strains were susceptible to a variety of antibiotics except for the penicillin G [1 IU/disc] resistance of B. tequilensis ST816CD. Both strains showed proteolytic activity. Additionally, both strains showed low hydrophobicity based on bacterial adherence measured by hydrocarbons (n-hexadecane).

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Strickland, Stephen L., Michael Shearer, and Karen E. Daniels. "Spatiotemporal measurement of surfactant distribution on gravity–capillary waves." Journal of Fluid Mechanics 777 (July 20, 2015): 523–43. http://dx.doi.org/10.1017/jfm.2015.352.

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Materials adsorbed onto the surface of a fluid – for instance, crude oil, biogenic slicks or industrial/medical surfactants – will move in response to surface waves. Owing to the difficulty of non-invasive measurement of the spatial distribution of a molecular monolayer, little is known about the dynamics that couple the surface waves and the evolving density field. Here, we report measurements of the spatiotemporal dynamics of the density field of an insoluble surfactant driven by gravity–capillary waves in a shallow cylindrical container. Standing Faraday waves and travelling waves generated by the meniscus are superimposed to create a non-trivial surfactant density field. We measure both the height field of the surface using moiré imaging, and the density field of the surfactant via the fluorescence of NBD-tagged phosphatidylcholine, a lipid. Through phase averaging stroboscopically acquired images of the density field, we determine that the surfactant accumulates on the leading edge of the travelling meniscus waves and in the troughs of the standing Faraday waves. We fit the spatiotemporal variations in the two fields using an ansatz consisting of a superposition of Bessel functions, and report measurements of the wavenumbers and energy damping factors associated with the meniscus and Faraday waves, as well as the spatial and temporal phase shifts between them. While these measurements are largely consistent for both types of waves and both fields, it is notable that the damping factors for height and surfactant in the meniscus waves do not agree. This raises the possibility that there is a contribution from longitudinal waves in addition to the gravity–capillary waves.

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Fuentes, E., H. Coe, D. Green, G. de Leeuw, and G. McFiggans. "Laboratory-generated primary marine aerosol via bubble-bursting and atomization." Atmospheric Measurement Techniques 3, no. 1 (February 5, 2010): 141–62. http://dx.doi.org/10.5194/amt-3-141-2010.

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Abstract. A range of bubble and sea spray aerosol generators has been tested in the laboratory and compared with oceanic measurements from the literature. We have shown that the method of generation has a significant influence on the properties of the aerosol particles produced. Hence, the validity of a generation system to mimic atmospheric aerosol is dependent on its capacity for generating bubbles and particles in a realistic manner. A bubble-bursting aerosol generator which produces bubbles by water impingement was shown to best reproduce the oceanic bubble spectral shapes, which confirms previous findings. Two porous bubblers and a plunging-water jet system were tested as bubble-bursting aerosol generators for comparison with a standard nebulizer. The methods for aerosol production were evaluated by analysing the bubble spectrum generated by the bubble-bursting systems and the submicron size distribution, hygroscopicity and cloud condensation nucleus activity of the aerosols generated by the different techniques. Significant differences in the bubble spectrum and aerosol properties were observed when using different aerosol generators. The aerosols generated by the different methods exhibited similar hygroscopicity and cloud condensation nucleus activity behaviour when a sample of purely inorganic salts was used as a parent seawater solution; however, significant differences in the aerosol properties were found when using samples of filtered natural seawater enriched with biogenic organics. The presence of organics in the aerosol caused suppression of the growth factor at humidities above 75% RH and an increase in the critical supersaturation with respect to the generation from artificial seawater devoid of organics. The extent of the effect of organics on the aerosol properties varied depending on the method of particle production. The results of this work indicate that the aerosol generation mechanism affects the particles organic enrichment, thus the behaviour of the produced aerosols strongly depends on the laboratory aerosol generator employed. Comparison between bubble lifetimes in several laboratory simulations and the oceanic conditions indicated that it would require a considerable extension of the dimensions of the currently used bubble-bursting laboratory systems in order to replicate the characteristic oceanic bubble lifetimes. We analyzed the implications derived from the reduced bubble residence times in scaled systems, regarding marine surfactants adsorption on rising bubbles, and found that adsorption equilibrium is reached on a timescale much shorter than the bubble lifetime in small-scale laboratory generators. This implies that adsorption of marine surface-active material is not limited by surfactant transport to the bubble surface.

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23

Kvamme, Bjørn. "Environmentally Friendly Production of Methane from Natural Gas Hydrate Using Carbon Dioxide." Sustainability 11, no. 7 (April 2, 2019): 1964. http://dx.doi.org/10.3390/su11071964.

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Huge amounts of natural gas hydrate are trapped in an ice-like structure (hydrate). Most of these hydrates have been formed from biogenic degradation of organic waste in the upper crust and are almost pure methane hydrates. With up to 14 mol% methane, concentrated inside a water phase, this is an attractive energy source. Unlike conventional hydrocarbons, these hydrates are widely distributed around the world, and might in total amount to more than twice the energy in all known sources of conventional fossil fuels. A variety of methods for producing methane from hydrate-filled sediments have been proposed and developed through laboratory scale experiments, pilot scale experiments, and theoretical considerations. Thermal stimulation (steam, hot water) and pressure reduction has by far been the dominating technology platforms during the latest three decades. Thermal stimulation as the primary method is too expensive. There are many challenges related to pressure reduction as a method. Conditions of pressure can be changed to outside the hydrate stability zone, but dissociation energy still needs to be supplied. Pressure release will set up a temperature gradient and heat can be transferred from the surrounding formation, but it has never been proven that the capacity and transport ability will ever be enough to sustain a commercial production rate. On the contrary, some recent pilot tests have been terminated due to freezing down. Other problems include sand production and water production. A more novel approach of injecting CO2 into natural gas hydrate-filled sediments have also been investigated in various laboratories around the world with varying success. In this work, we focus on some frequent misunderstandings related to this concept. The only feasible mechanism for the use of CO2 goes though the formation of a new CO2 hydrate from free water in the pores and the incoming CO2. As demonstrated in this work, the nucleation of a CO2 hydrate film rapidly forms a mass transport barrier that slows down any further growth of the CO2 hydrate. Addition of small amounts of surfactants can break these hydrate films. We also demonstrate that the free energy of the CO2 hydrate is roughly 2 kJ/mol lower than the free energy of the CH4 hydrate. In addition to heat release from the formation of the new CO2 hydrate, the increase in ion content of the remaining water will dissociate CH4 hydrate before the CO2 hydrate due to the difference in free energy.

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KARPENKO, Іlоna, Galyna MIDYANA, Olena KARPENKO, Igor SEMENIUK, Stepan MIDYANYY, and Olena PAL’CHIKOVA. "APPLICATION OF EXTRACTION METHOD FOR ISOLATION OF BIOGENIC SURFACE-ACTIVE RHAMNOLIPIDS." Proceedings of the Shevchenko Scientific Society. Series Сhemical Sciences 2020, no. 60 (February 25, 2020): 7–13. http://dx.doi.org/10.37827/ntsh.chem.2020.60.007.

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The priority task of modern biotechnology is development of the rational technologies for the microbial synthesis of practically important products. Among these products, a significant place belongs to surfactants (biosurfactants), which are widely used in many sectors of the economy. The most problematic stage of the biosurfactants production is isolation from the post fermentative cultural liquid of bacteria-producers. Improving the efficiency of the biosurfactants production is highly dependent on rational approaches to the target products isolation. In this regard, there is an increasing need for rational, scientifically substantiated methods for their isolation and purification. Therefore, the aim of the presented work was to determine the optimal extractants for the isolation of rhamnolipid surfactants – metabolites of bacteria of Pseudomonas sp. PS-17 strain. For this purpose, the extraction process of rhamnolipids from the post fermentative cultural liquid supernatant has been investigated. The optimal extractants were selected among 13 organic solvents of different nature. Processing of the obtained experimental data by the method of multi-parameter equations of linearity of free energies (modified Koppel-Palm equation) made it possible to establish the relationship between the physicochemical properties of the extractants and amounts of the biosurfactants which were isolated from cultural liquid supernatant. It was shown that the data on the rhamnolipids extraction are adequately associated with the physicochemical characteristics of the solvents using a six-parameter linear equation. It was determined that the polarizability and molar volume are the main properties of solvents that affect the extraction process. The best extractants for the rhamnolipids isolation from cultural liquid supernatant of the Pseudomonas sp. PS-17 strain are the ethers. It can be explained by the presence of a lone pair of the electrons of oxygen in its molecule. The obtained results of the study are of scientific interest for isolation of the important and perspective biotechnological products – surface-active substances.

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Nikolova, Christina N., Umer Zeeshan Ijaz, Clayton Magill, Sara Kleindienst, Samantha B. Joye, and Tony Gutierrez. "Response and oil degradation activities of a northeast Atlantic bacterial community to biogenic and synthetic surfactants." Microbiome 9, no. 1 (September 21, 2021). http://dx.doi.org/10.1186/s40168-021-01143-5.

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Abstract Background Biosurfactants are naturally derived products that play a similar role to synthetic dispersants in oil spill response but are easily biodegradable and less toxic. Using a combination of analytical chemistry, 16S rRNA amplicon sequencing and simulation-based approaches, this study investigated the microbial community dynamics, ecological drivers, functional diversity and robustness, and oil biodegradation potential of a northeast Atlantic marine microbial community to crude oil when exposed to rhamnolipid or synthetic dispersant Finasol OSR52. Results Psychrophilic Colwellia and Oleispira dominated the community in both the rhamnolipid and Finasol OSR52 treatments initially but later community structure across treatments diverged significantly: Rhodobacteraceae and Vibrio dominated the Finasol-amended treatment, whereas Colwellia, Oleispira, and later Cycloclasticus and Alcanivorax, dominated the rhamnolipid-amended treatment. Key aromatic hydrocarbon-degrading bacteria, like Cycloclasticus, was not observed in the Finasol treatment but it was abundant in the oil-only and rhamnolipid-amended treatments. Overall, Finasol had a significant negative impact on the community diversity, weakened the taxa-functional robustness of the community, and caused a stronger environmental filtering, more so than oil-only and rhamnolipid-amended oil treatments. Rhamnolipid-amended and oil-only treatments had the highest functional diversity, however, the overall oil biodegradation was greater in the Finasol treatment, but aromatic biodegradation was highest in the rhamnolipid treatment. Conclusion Overall, the natural marine microbial community in the northeast Atlantic responded differently to crude oil dispersed with either synthetic or biogenic surfactants over time, but oil degradation was more enhanced by the synthetic dispersant. Collectively, our results advance the understanding of how rhamnolipid biosurfactants and synthetic dispersant Finasol affect the natural marine microbial community in the FSC, supporting their potential application in oil spills.

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Banerjee, Aparna, Shrabana Sarkar, Tanvi Govil, Patricio González-Faune, Gustavo Cabrera-Barjas, Rajib Bandopadhyay, David R. Salem, and Rajesh K. Sani. "Extremophilic Exopolysaccharides: Biotechnologies and Wastewater Remediation." Frontiers in Microbiology 12 (August 19, 2021). http://dx.doi.org/10.3389/fmicb.2021.721365.

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Various microorganisms thrive under extreme environments, like hot springs, hydrothermal vents, deep marine ecosystems, hyperacid lakes, acid mine drainage, high UV exposure, and more. To survive against the deleterious effect of these extreme circumstances, they form a network of biofilm where exopolysaccharides (EPSs) comprise a substantial part. The EPSs are often polyanionic due to different functional groups in their structural backbone, including uronic acids, sulfated units, and phosphate groups. Altogether, these chemical groups provide EPSs with a negative charge allowing them to (a) act as ligands toward dissolved cations as well as trace, and toxic metals; (b) be tolerant to the presence of salts, surfactants, and alpha-hydroxyl acids; and (c) interface the solubilization of hydrocarbons. Owing to their unique structural and functional characteristics, EPSs are anticipated to be utilized industrially to remediation of metals, crude oil, and hydrocarbons from contaminated wastewaters, mines, and oil spills. The biotechnological advantages of extremophilic EPSs are more diverse than traditional biopolymers. The present review aims at discussing the mechanisms and strategies for using EPSs from extremophiles in industries and environment bioremediation. Additionally, the potential of EPSs as fascinating biomaterials to mediate biogenic nanoparticles synthesis and treat multicomponent water contaminants is discussed.

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Zamshin, V. V., E. R. Matrosova, V. N. Khodaeva, and O. I. Chvertkova. "Quantitative Approach to Studying Film Pollution of the Sea Surface Using Satellite Imagery." Physical Oceanography 28, no. 5 (October 2021). http://dx.doi.org/10.22449/1573-160x-2021-5-567-578.

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Purpose. Numerous studies of various film pollutions (oil spills, surfactants etc.) are performed by means of satellite monitoring of seas and oceans. However, the problem of formal ranking the water areas of the regions under study by frequency and intensity of pollution is still unsolved. The conditions and periodicity of satellite survey can differ greatly depending on the monitoring region that determines both spatial variability of the probability of film pollution detection and the need to take this feature into consideration. Here we attempt to develop a quantitative approach to studying the sea surface film pollutions based on processing of large volumes of satellite optical and radar imagery. Methods and Results. The concept “index of sea surface exposure to film pollutions”, dfpMON, and the method for calculating its quantitative value on a regular spatial grid are proposed. The value of dfpMON is defined as a ratio of the pollution area observed at the site to the area of the analyzed resolution elements (where detection of film pollution is theoretically possible). Within the framework of this approach, the already existing methods for analyzing the results of long-term satellite seawater pollution monitoring were improved due to taking into account the meteorological conditions and the spatial distribution of the observation amount. Having been applied, the proposed approach permitted to study spatial distribution of the non-biogenic film pollutions in the northern part of the Black Sea; they were detected resulting from interpretation of 4428 satellite images obtained in 2019 by the Landsat-8, Sentinel-2A/B and Sentinel-1A/B satellites (2499 cases of pollution processed). The average value of the dfpMON index was 0.012%. Three regions, where the dfpMON values exceeded the average one by more than 30 times were identified. Conclusions. The example of a site in the northern Black Sea has shown the possibility of obtaining representative information products of satellite oceanography, which quantitatively characterize spatial variability of the sea surface film pollution recorded during the long-term episodes of satellite monitoring.

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Zamshin, V. V., E. R. Matrosova, V. N. Khodaeva, and O. I. Chvertkova Chvertkova. "Quantitative Approach to Studying Film Pollution of the Sea Surface Using Satellite Imagery." Morskoy gidrofizicheskiy zhurnal 37, no. 5 (September 2021). http://dx.doi.org/10.22449/0233-7584-2021-5-610-622.

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Анотація:

Purpose. Numerous studies of various film pollutions (oil spills, surfactants etc.) are performed by means of satellite monitoring of seas and oceans. However, the problem of formal ranking the water areas of the regions under study by frequency and intensity of pollution is still unsolved. The conditions and periodicity of satellite survey can differ greatly depending on the monitoring region that determines both spatial variability of the probability of film pollution detection and the need to take this feature into consideration. Here we attempt to develop a quantitative approach to studying the sea surface film pollutions based on processing of large volumes of satellite optical and radar imagery. Methods and Results. The concept “index of sea surface exposure to film pollutions”, dfpMON, and the method for calculating its quantitative value on a regular spatial grid are proposed. The value of dfpMON is defined as a ratio of the pollution area observed at the site to the area of the analyzed resolution elements (where detection of film pollution is theoretically possible). Within the framework of this approach, the already existing methods for analyzing the results of long-term satellite seawater pollution monitoring were improved due to taking into account the meteorological conditions and the spatial distribution of the observation amount. Having been applied, the proposed approach permitted to study spatial distribution of the non-biogenic film pollutions in the northern part of the Black Sea; they were detected resulting from interpretation of 4428 satellite images obtained in 2019 by the Landsat-8, Sentinel-2A/B and Sentinel-1A/B satellites (2499 cases of pollution processed). The average value of the dfpMON index was 0.012 %. Three regions, where the dfpMON values exceeded the average one by more than 30 times were identified. Conclusions. The example of a site in the northern Black Sea has shown the possibility of obtaining representative information products of satellite oceanography, which quantitatively characterize spatial variability of the sea surface film pollution recorded during the long-term episodes of space monitoring.

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