The accumulation of carbon dioxide (CO2) in the atmosphere, as well as pollution ofwater objects with heavy metals, are environmental problems associated with numerous impacts onecosystems. The cultivation of photosynthetic microorganisms that efficiently absorb CO2 is a promisingsolution, since the biomass of cyanobacteria can be used to produce valuable bioproducts. Interest inthe effect of high concentrations of CO2 on the activity of cyanobacteria is growing in connection withstudies of cleaning the atmosphere from industrial pollution using cyanobacteria as biofilters, due totheir ability to grow rapidly in conditions of high CO2 content in the atmosphere. Cyanobacteria are aconvenient object for research due to the high growth rate and controllability of their biosynthesis. Thisarticle presents the results of the influence of different concentrations of carbon dioxide on the productivity of strains of cyanobacteria. Resistance to inhibitory concentrations of CO2 is species-specific andvaries over a wide range of values. The effect of carbon dioxide at a concentration of 2%, 4%, and 8%on the growth rate of cyanobacteria was studied, and a comparative assessment of the effect of increasedcarbon dioxide concentrations on biomass growth from the readings of optical density and fluorescenceactivity was carried out. It was determined that carbon dioxide concentrations of 2-4% have a positive effect on the productivity of the studied cultures of cyanobacteria. It was found that increasing the concentration of CO2 to 8% leads to a decrease in growth rates of cyanobacteria. It was determined that thestrain Cyanobacterium sp. IPPAS B-1200 was selected as the most productive strain from the studied cyanobacteria according to the yield of dry biomass, fluoresce activity and characterized by active growthat a concentration of CO2 in air – 4%.Key words: Carbon dioxide, cyanobacteria, biomass productivity, fluorescence activity

Cyanobacterium sp. IPPAS B-1200 характеризуется высоким содержанием в мембранных липидах таких жирных кислот (ЖК) как миристиновая (14:0-30%) и миристолеиновая (14:1 9-10%). Таким образом, “короткие” ЖК составляют 40% от общей массы ЖК, что крайне необычно для цианобактерий. Мононенасыщенная пальмитолеиновая кислота (16:1 9) также достигает 40% от суммы ЖК. Мы определили нуклеотидную последовательность генома этой цианобактерии и обнаружили в нем лишь один ген десатуразы ЖК, кодирующий ацил-липидную 9-десатуразу DesC1. Для определения спе- цифичности DesC1 к длине ЖК этот ген клонировали и экспрессировали в клетках Escherichia coli. Результаты показывают, что десатураза DesC1 проявляет активность в положении 9 неспецифично по отношению к длине цепи ЖК и способна образовывать двойные связи в С14, С16 и С18 ЖК. Это свидетельствует о том, что наличие всех мононесащенных кислот в клетках Cyanobacterium определяется активностью одной единственной 9-десатуразы.

Chlorophyll b -containing cyanobacterium Prochlorothrix hollandica is characterized by a high content of esterified fatty acids (FA) with 14 and 16 carbon atoms in the membrane lipids. Depending on the conditions of cultivation, the relative amount of myristic (C 14:0 ) and myristoleic (C 14:1 ) acids can reach 35%, and palmitic (С 16:0 ) and palmitoleic (С 16:1 ) acids can reach 60% of the sum of all fatty acids in cells. Monounsaturated FAs are represented by C 14:1 , and C 16:1 with an olefinic bond presumably located in the Δ 9 position. We cloned the gene of acyl-lipid Δ9-desaturase, desC1 , from Prochlorothrix hollandica and characterized its specificity to the length of the substrate using the heterologous expression in Escherichia coli cells adding C 14:0 or stearic (C 18:0 ) acids as exogenous substrates. The results show that DesC1 Δ 9 desaturase generates olefinic bonds in the FAs with a length of 14 to 18 carbon atoms with an approximately equal efficiency. This indicates that the length of the FA chain in P. hollandica is determined by the activity of the FA synthase, and the chain is desaturated at the Δ 9 position nonspecifically relatively to its length.

Plankton filament cyanobacteria Prochlorothrix hollandica is characterized by a very high content of C14 and C16 fatty acids (FA) in the lipid membranes. Depending on culturing conditions of the cyanobacteria, total concentrations of myristic and myristoleic acids can reach 35% and those of palmitic and palmitoleic acids can reach 60% of all esterified FA cells. In P. hollandica, a variety of monounsaturated FA is represented by myristoleic and palmitic acids, and by hexadecenoic (C16:1) acid with olefin bond of cis-configuration, located in the Δ4 position. The process of intensive culturing for P. hollandica cells to yield a maximal biomass in order to isolate the pure drug of myristoleic acid derivative has been optimized. The use of a threestage purification gives 30 mg of chromatographically pure myristoleic acid methyl ester from 17 g of P. hollandica raw biomass (dry mass is 3 g), which is 1% of dry cell mass.

Algalogically pure cultures were isolated from different aquatic ecosystems and identified as representatives of green algae, euglena algae, and cyanobacteria. Isolated cultures and collection strains of microalgae were screened for productivity. Induced mutagenesis (exposure to UV radiation, 254 nm, 40 Erg/mm(2)) and selection yielded a mutant strain C-2m2 of Chlorella pyrenoidosa notable for a high activity of lipid biosynthesis and accumulation. Optimization of its culture conditions was conducted. It was found that the active lipid accumulation by the cells of C. pyrenoidosa strain C-2m2 occurred when nitrogen concentration in the medium was tenfold reduced (to the level of 0.004 g/L) at an illuminance of 4 klx.

В результате массового культивирования активного штамма микроводоросли Chlorella vulgaris-1 на сточной воде в соотношении 1:1 к питательной среде, максимум роста приходится на 16 сутки культивирования, численность клеток при этом составляет - 50х106 кл/мл,. Биохимический анализ клеток штамма Chlorella vulgaris-1 показал содержание белков составляет 35%, углеводов - 29%, липидов - 30% и золы – 6% от сухого веса, что свидетельствуют о возможности использования штамма Chlorella vulgaris-1 с двойной пользой как в экологической биотехнологии, так и в биоэнергетике. Определен жирнокислотный состав биомассы активного штамма микроводоросли Chlorella vulgaris-1 Ластанған сумен қоректік ортаның 1:1 қатынасында микробалдырлар Chlorella vulgaris-1 белсенді штамын жаппай дақылдау нəтижесінде, олардың жоғарғы өсімі 16-күні байқалды. Бұл кездегі клеткалар саны 50х106 кл/мл-ді көрсетті. Chlorella vulgaris-1 клетка штамының биохимиялық анализі мынадай көрсеткіштер көрсетті:белок 35%, көмірсу - 29%, липид - 30% жəне күлділігі құрғақ салмақтың – 6%-н көрсетті, яғни Chlorella vulgaris-1 штамын 2 жақты пайдалы экологиялық биотехнология мен биоэнергетикада пайдалануға болатынын көрсетеді. Микробалдыр Chlorella vulgaris-1 активті штамы биомассасының майқыщқылдық құрамы анықталды.