Studies of pesticide effects on Chlorella metabolism I. Effect of herbicides on complex lipid biosynthesis

Various herbicides were tested for possible effects on biosynthesisof complex lipids in Chlorella using ¹⁴C-U-acetate as a precursor.Among the herbicides tested, Hill reaction inhibitors causedinhibition of ¹⁴C-incorporation by 60 to 80 per cent at a concentrationof 5 mg/liter, and noticeable alteration in the labeling patternof glyco- and phospholipids. Proportions of mono- and digalactolipidsmarkedly decreased while those of phosphatidyl ethanolamineand phosphatidyl glycerol increased. In terms of net synthesis,phosphatidyl ethanolamine was affected, if at all, only slightlyby Hill reaction inhibitors, while the other complex lipidsdecreased to various degrees. (Received February 9, 1973; )