Fig. 4.

Effects of B resupply on cell death and the accumulation of lipid peroxides. (a) Number of dead cells. Duplicate cultures were deprived of B, and then supplemented after 18 h with either boric acid at 1 mg B liter^–1 (‘resupplied culture’) or water (‘−B culture’). Cells washed with and cultured in control medium were also prepared as a control (‘+B culture’). Aliquots of the cell suspensions were withdrawn and dead cells were counted after FDA/PI staining. Each value is an average of the results of six independent counts. (b) Lipid peroxide contents. Cells were treated as in (a) and their lipid peroxides were quantified as in Fig. 2e. Each value is the mean of two replicates, and the error bar represents the difference between replicates.