ANTIMICROBIAL ACTIVITIES OF TANNINS EXTRACTED FROM RHIZOPHORA APICULATA BARKS

Abstract

LIM, S. H., DARAH, I. & JAIN, K. 2006. Antimicrobial activities of tannins extracted from Rhizophora
apiculata barks. Tannin which was extracted from barks of Rhizophora apiculata was further separated into
hydrolysable and condensed tannin. The results of the study revealed that only hydrolysable tannin
showed significant antibacterial and antiyeast activities but not antifungal activity. The minimum inhibitory
concentration (MIC) and minimum bactericidal concentration (MBC) values of the tannin against bacteria
and yeasts were also determined. Special attention was given to hydrolysable tannin which exhibited a
significant antiyeast activity. The hydrolysable tannin was further tested in vitro for antifungal activity
against Candida albicans, a pathogenic yeast which sometimes causes infection in human and animals.
SEM and TEM microscopy studies revealed that the treated cells of C. albicans demonstrated severe
morphological changes especially on its cell wall and cell membrane.