2016, Vol. 4, Issue 3, Part D

author(s)
Tanvir Ahmad, M Kamruzzaman, Md. Mominul Islam, Md. Hasanuzzaman, Asif Ahmed and Dipak Kumar Paul

abstract
In this Study to evaluate the anti-microbial activity of Long pepper (Piper longum) and watercress (Enhydra fluctuans), the sample plants are collected from four different districts of Bangladesh. Plant parts were extracted by distilled water and organic solvent like ethanol or chloroform or acetone. The antimicrobial properties of the extracts were evaluated on five strains of bacteria e.g. Staphylococcus aureous, Staphylococcus saprophyticus, E. coli, Salmonella typhi and shigelladysenteri. Different labeled sterile paper discs are used for sample discs, discs for negative control and standard antibiotic discs. The antimicrobial activity (by measuring inhibition zone diameter) of various extracts were observed. The chloroform and ethanol extracts of both plants have potent against Staphylococcus saprophytias and Staphylococcus aureus with highest zone of inhibition among the tested bacterial strains like 23mm. Similarly ethanol extracts of both plants were more effective against Staphylococcus saprophyticus than any other microorganisms. Acetone extract of long pepper was more effective and produced maximum zone of inhibition of 22mm and watercress of same extract produced 21mm on Staphylococcaceae. Comparatively aqueous extract of Watercress was least effective against Shigella Dysenteriae. The standard antibiotic disc was compared with the plant extract and shown that Tetracycline, Cephradine and Naldixic acid was more potent in producing the zone of inhibition against the same microorganism tested. Ciprofloxacin, Penicillin –G and amoxicillin was less potent in producing the zone of inhibition). Finally different extracts from the both plants shown a strong antibacterial activity with MIC<128 𝜇g/ml, indicating that these plants could be a potent source of antibacterial agent to battle multi drug resistance (MDS) bacterial infection.