Academic literature on the topic 'Biogenic–surfactants'

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.

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.

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.

Дисертація присвячена розробленню технології отримання поверхнево-активних речовин штаму Pseudomonas sp. PS-17 та технологій їх застосування для вирощування олійних рослин. Встановлено ефективність використання економічно вигідних субстратів (фузу олійного, пересмаженої олії), композицій їх з гліцерином, а також дробного способу їх подачі для синтезу рамноліпідних ПАР: вихід підвищено на 18-39% порівняно з гліцерином. Удосконалено способи виділення ПАР, одержано економічно вигідні продукти. Методом лінійних багатопараметрових рівнянь визначено оптимальні екстрагенти рамноліпідів. Показано, що отримані ПАР мають високу поверхневу (28,3 мН/м), емульгувальну (індекс Е24 60-80%), змочувальну активність, впливають на проникність клітинних мембран мікроорганізмів, рослин, підсилюють дію біоцидів, фітогормонів. Встановлено стимулювальний вплив ПАР на ріст олійних рослин, їх фізіолого-біохімічны показники. Ефективність отриманих ПАР у вирощуванні соняшника доведено у дрібноділянкових і виробничому дослідах: за їх використання значно підвищувалися ростові показники та якість врожаю. Розроблено технологічну та апаратурно-технологічну схему виробництва ПАР штаму Pseudomonas sp. PS-17, яка дозволяє одержати 5 форм цільових продуктів для практичного застосування у рослинництві.
The dissertation thesis is devoted to the development of the biotechnology of microbial synthesis of the surface-active substances by the strain Pseudomonas sp. PS-17 and their application in cultivation of oil-bearing plants. The effectiveness of the application of cost-beneficial substrates (used frying oil and waste from production of sunflower oil – phosphatide concentrate) was established for the synthesis of rhamnolipid surfactants by the strain Pseudomonas sp. PS-17 when applied alone and in combination with glycerol. It was shown that the use of combined substrates contributed to the increased yields of rhamnolipids if compared to the media with monosubstrates. When using a mixture of glycerol and used frying oil or phosphatide concentrate as carbon sources the final concentration of rhamnolipids can be increased on 18-39 %. The developed approaches of the synthesis of rhamnolipid surfactants will enable the decrease of the overall cost of biosurfactant production if compared with the cost of the production on glycerol alone. The processes of rhamnolipid surfactant separation were optimized: enzymatic hydrolysis (using protease C enzyme) of post-fermentative culture liquid, precipitation of rhamnolipid biocomplex (RBC) from culture liquid supernatant (CLS) by adjusting temperature regime. Economically viable forms of targeted products based on exo- and endomethabolites of Pseudomonas sp. PS-17 and methods of their isolation were proposed. Optimum solvents for the extraction of rhamnolipids from CLS were determined using the method of linear multiparameter equations. Physico-chemical and biological properties of the products based on surfactants of Pseudomonas sp. PS-17 were established: surface activity, emulsification of hydrophobic substances, wetting of surfaces, the influence on the permeability of cell membranes of microorganisms and plants, the activity of surfactants on the major groups of phytohormones (auxins, cytokinins, gibereline acid). The antimicrobial activity of surfactants against phytopathogen microorganisms was shown, and highly effective formulations of rhamnolipid surfactant with ethylthiosulfonate-biocide were designed. A stimulating action of the synthesized rhamnolipid surfactants on the growth of oil-bearing plants was established. It was shown that the effect of the biosurfactants on microorganisms and plants via the changes in their physiological and biochemical characteristics (growth rate, cell membrane permeability, activity of enzymes and phytohormones). The possibility of application of the obtained biosurfactants in agriculture as plant growth regulators was established. The effectiveness of the developed biosurfactants in growing sunflower was confirmed by a small plot experiments, as well as in the field experiment. It was shown that rhamnolipid surfactants promote growth and quality of the crops (the mass of 1000 seeds, flower diameter, fat and protein content in the seeds). The process flow and equipment diagrams of industrial production of rhamnolipid surfactants of Pseudomonas sp. PS-17 using a vortex bioreactor were developed, 5 forms of rhamnolipid products for practical use in cropping were obtained.
Диссертация посвящена разработке технологии синтеза поверхностно-активных веществ штаммом Pseudomonas sp. PS-17 и их применению для выращивания масличных растений. Установлена эффективность использования экономически выгодных субстратов (фуза масляного, пережаренного масла), их смесей с глицерином, дробного способа их подачи для синтеза рамнолипидных ПАВ, выход увеличен на 18-39% относительно глицерина как моносубстрата. Усовершенствованы способы выделения рамнолипидных ПАВ, получены экономически выгодные продукты. Методом линейных многопараметровых уравнений найдены оптимальные экстрагенты рамнолипидов из СКЖ. Разработанные ПАВ имеют высокую поверхностную (28,3 мН/м), эмульгирующую (индекс Е24 60-80%), смачивающую активность, влияют на проницаемость клеточных мембран микроорганизмов, растений, усиливают действие биоцидов, фитогормонов. Показано стимулирующее действие полученных ПАВ на рост масличных растений, их физиолого-биохимических показателей. Эффективность рамнолипидных ПАВ при выращивании подсолнечника установлена в мелкоучастковых, производственных опытах: значительно увеличены ростовые показатели, а также качество урожая. Разработана технологическая и аппаратурно-технологическая схемы промышленного производства рамнолипидных ПАВ Pseudomonas sp. PS-17 для получения 5 форм продуктов для практического применения в растениеводстве.