Phototrophic bacterial production of oleic acid in an illuminated upflow anaerobic sludge blanket reactor

Phototrophic bacterial cells in the effluent from a lighted upflow anaerobi c sludge blanket reactor supplied with a medium containing 142 mg S (as SO4 2-) l(-1) accumulated a 6.8% w/w oleic acid content in cells and 19 mg cell -bound oleic acid l(-1) in the effluent. Pure cultures of Rhodopseudomonas palustris and Blastochloris sulfoviridis isolated from the effluent also ac cumulated 5.1 and 6.4% w/w oleic acid contents in cells, respectively. The oleic acid content in the cells recovered from the LUASB reactor effluent w as related to the phototrophic bacterial population in the LUASB reactor. T he inverse relationship was observed in the LUASB reactor between phototrop hic bacterial growth and sulfate concentration in the influent.