Time of incubation for lipase production by wild-type (Isl-9) and mutant strain (EM-7) of R. oligosporus. Almond meal 15 g, moisture 12.5 ml tris-HCl, pH 7, temperature 30°C. Y-error bars state standard deviation (±SD 5%) among the values of three parallel replicates. For symbols, see Figure 1.