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The lipid composition of the green alga Botryococcus was studied at three different cultivation temperatures: suboptimal, optimal, and supraoptimal. Cultivation at the supraoptimal temperature was found to considerably inhibit the synthesis of nearly all intracellular lipids, except for triacylglycerides, and to influence their fatty acid composition. In particular, the content of trienoic fatty acids was significantly lower at the supraoptimal than at the optimal cultivation temperature. At the same time, the fatty acid composition of the extracellular lipids of the alga virtually did not depend on cultivation temperature.

The composition of lipids was studied in three strains of carboxydobacteria, viz. Seliberia carboxydohydrogena Z-1062, Pseudomonas gazotropha Z-1156 and Comamonas compransoris Z-1155. The content of lipids extracted with an alcohol--chloroform mixture varied in these strains from 9 to 13.2%. The main classes were phospholipids (from 62.6 to 77.2% of the overall lipid content). The major phospholipids were phosphatidyl ethanolamine and phosphatidyl choline. Moreover, the strains Z-1062 and Z-1156 contained three unidentified phospholipids which constituted 40 and 20% of the total content respectively. The neutral lipids of the carboxydobacteria comprised diglycerides, triglycerides, free fatty acids, methyl esters of fatty acids and a number of compounds which were not identified. The fatty acids of the strains were represented by saturated, monoene and cyclopropanoic acids. The main acids were palmitic, palmitolenic, C17-cyclopropanoic, stearic and octadecenic acids. Polar lipids differed from neutral lipids in their fatty acid composition. The fatty acid composition of firmly bound lipids was characterized by a high degree of saturation, the absence of cyclopropanoic acids and the presence of two unidentified acids that were not found in free lipids; apparently, they belonged to hydroxy acids.

The composition of lipids was studied in the luminescent bacterium Photobacterium mandapamensis under the conditions of maximal luminescence. The synthesis of total lipids and poly-beta-hydroxybutyric acid (PHBA) was investigated in dynamics under the conditions of batch cultivation. The major class of lipids was polar lipids (84.3%) represented by phospholipids (phosphatidyl ethanolamine, phosphatidyl glycerol, cardiolipin, lysocardiolipin, lysophosphatidyl ethanolamine) and a minor nonidentified phospholipid. The fraction of neutral lipids was represented mainly by free fatty acids (about 5%), tri- and diglycerides (in trace amounts), and two nonidentified classes, apparently, hydrocarbons and waxes. A correlation was established between the luminescence of the bacterium and the content of PHBA.