Identification of Bioactive Compounds from Alphonsea madraspatana Leaves against Multi Drug Resistance Bacteria

Abstract

In this study, the antimicrobial compounds present in leaves of Alphonsea madraspatana was identified by using RP-HPLC, LC/MS and GC/MS and found to be active against multiple drug resistant (MDR) bacteria e.g. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Extraction of dried plant leaves was performed by solvent gradient technique. Antimicrobial study was performed with each extract. n-Hexane and methanol extracts were further subjected to analysis for identification of potent antimicrobial compounds due to their better antimicrobial activity as compared to remaining extracts. The methanolic extract was more active than n-hexane extract. As n-hexane extract contains non-polar compounds, it was subjected to GC-MS analysis and methanol extract was subjected to RPHPLC followed by LC/MS due to presence of polar components. Among the isolated compounds, four compounds were identified as potent antimicrobial. RP-HPLC and LC/MS analysis of methanol extract also ensured the presence of four potent antimicrobial compounds as follows: (i) kaempferol-3-O-rotinoside-orhamnoside (m/z 748), (ii) 3-hydroxypropylglucosinolate (m/z 377), (iii) luteolin-7-O-glucoside (m/z 448) and (iv) genistein-7-O-glycoside (m/z 432). Leaves of this plant may be used as potent antibacterial agents due to presence of antimicrobial compounds.