Antimicrobial efficacy and phytochemical analysis of Albizia amara (Roxb.) Boiv. an indigenous medicinal plant against some human and plant pathogenic bacteria and fungi
The present investigation evaluates the antimicrobial activity of six different solvent exts. and isolated constituents of leaves of Albizia amara against a total of 21 microorganisms which consisted of seven human pathogenic bacteria, a phytopathogenic Xanthomonas campestris (NCIM 2954) and thirteen seed-borne phytopathogenic fungi. Our result showed that, among the six solvent exts. tested, the chloroform ext. showed a higher antibacterial and antifungal activity followed by methanol, ethanol and hydro-methanolic exts. resp. The chloroform, methanol and ethanol exts. exhibited antibacterial activity with zone of inhibition ranging from 5.25 to 23.75, 6.25 to 23.25 and 7.25 to 22.7 mm resp. at 1mg/mL concn. The minimal inhibitory concn. (MIC) of the chloroform ext. ranged from 15μg/mL to 500μg/mL depending upon bacterial species. The most susceptible organism in the present investigation was Streptococcus faecalis (NCIM 5025), while the most resistant was Proteus vulgaris (NCIM 2027). Highest antifungal activity was obsd. in chloroform ext. followed by methanol ext. with percent of inhibition ranging from 30% to 77.4% and 17.4% to 71.7% resp. The IC50 value of chloroform ext. ranged from 0.5mg/mL to 5.0mg/mL depending upon fungal species. Among the tested fungi, Fusarium lateratum was highly sensitive and Aspergillus flavus was least sensitive. Chloroform ext. was subsequently fractionated and monitored for antibacterial activity guided assay leading to the isolation of active fraction and was confirmed as alkaloid by further phytochem. anal. The present study thus confirms antimicrobial property of A. amara and also demonstrated the role of A. amara used in traditional medicine
