Antibiotic activity of [Indian] bryophytes

This study is concerned with an examination of the antibiotic activity of 52 species (in 40 genera) of the bryophytes. The plants were extracted in water, methanol, ethanol, ether and acetone and tested against 12 microorganisms, including 3 Gram positive (Staphylococcus aureus, a penicillin-sensitive and penicillin-resistant strain, Sarcina lutea and Bacillus subtilis), 5 Gram negative (Escherichia coli, Salmonella typhi, Vibrio cholerae, Klebsiella pneumoniae and Pseudomonas aeruginosa), one acid-fast bacterium (Mycobacterium phlei) and 3 fungi (Curvularia lunata, Aspergillus niger and Helminthosporium oryzae). Solubility data and antibiotic spectra of the active plants indicate the occurrence of a variety of antibiotic substances among bryophytes. Out of 52 species of bryophytes, 29 (56%) were active against at least one of the test bacteria, but none possessed any antifungal property. The occurrence of antibiotic substances seems to be more frequent in hepatics than in mosses and anthocerotopsids. Antibiotic activity was particularly prominent in the Rebouliaceae, where all 5 species tested were active. The moss Brachythecium procumbens and the liverworts Asterella sanguinea and Marchantia paleacea showed the broadest spectrum of antibiotic activity. Among the test organisms used Salmonella typhi was found to be most sensitive.