Abstract
We experimented what components of soybean oil gave a remarkable effect on penicillin yield when added in the shaking culture of P. chrysogenum as antifoam agents and obtained the following results.
(1) Oleic acid showed decrease in penicillin yield or no increase when added to the medium at the time of sterilization, but revealed a remarkable increase in potency when added during 24 to 48 fermentation hours in a relatively high percentage up to 0.5%.
(2) Glycerol showed no remarkable effect.
(3) Saturated fatty acids showed no remarkable effect but palmitic acid had a little unfavorable effect and stearic acid less than 0.1% showed the increase in potency. (Lauric acid worked as stimulant next to oleic acid).
(4) Oleic acid in 0.5% showed the same effect with or rather a little better than 0.5% of soybean oil and the use of oleic acid together with phenylacetic acid showed more remarkable results than the separate use of the two.
Judging from the above results, we are convinced that we have chosen a splendid formula of antifoam agents of natural fats and oils which give interesting results.
