Abstract
The authors have succeeded in isolating an antibiotic, from the cultured filtrate of Asp. oryzae, responsible for, at least, the majority of the active substances against hiochi-bacteria, as pale yellow crystals of m.p. 152_??_153°C. It has been proved that this antibiotic is identical with hydroxyasper-gillic acid. The minimum concentration for complete inhibition in diluted Saké-peptone medium against true hiochi-bacilli, Lactobacillus homohiochii H-42 and Lactobacillus heterohiochii H-1, was 10 γ/ml, and that against hiochi-lactobacilli H-7 and H-34 20γ/ml.