Antimicrobial Properties of Derris scandens Aqueous Extract

Journal of Biological Sciences 01/2009; DOI: 10.3923/jbs.2009.607.611
Source: DOAJ

ABSTRACT The objective of this study is to evaluate the antimicrobial activity of D. scandens aqueous extract against various bacteria. The stems of D. scandens were extracted using aqueous extraction with yield 1.5-2% of dried weight of plant stems. The antimicrobial activity was screened by using agar diffusion method. Minimum Inhibitory Concentrations (MICs) and MBCs values were determined using agar dilution method and broth macro-dilution method. The agar diffusion tested revealed that the plant aqueous extract showed inhibition zone against S. aureus ATCC 25923, S. epidermidis ATCC 12228 and E. coli ATCC 25922. Among three bacteria, S. aureus and S. epidermidis is gram positive bacteria, while E. coli is gram negative bacteria. Minimum Bactericial Concentration (MICs) of the plant aqueous extract were in range of 2-4 g L-1, while MBCs were in the range of 4-16 g L-1. In conclusion, the plant extract showed good inhibitory effect on growth of S. aureus and E. coli which are nosocomial infection bacteria and those S. epidermidis which is normal flora.

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