Studies on Alkaloids of Streptomyces

A method was given for determination of alkaloids in culture filtrates using alkaloid reagents, e.g., modified Dragendorff’s and Mayer’s reagents, in conjunction with several pharmacological tests such as Magnus method employing the isolated guinea pig intestine and the influence on blood pressure etc. In a screening of about 1250 strains of actinomycetes, 8 strains yielded basic materials that gave positive reaction with both of the above reagents. Among them, HCI extract from the culture filtrate of Streptomyces strain No. FFD-101 caused a transient drop of blood pressure of rabbit. Furthermore one fraction of HCI extracts from the culture filtrate of Streptomyces strain 227 × 1 caused a continous rise of blood pressure.