A bioassay-guided fractionation scheme for characterization of new anti- bacterial compounds from Prosopis cineraria aerial parts
Neghabi-Hajiagha، Mahdieh نويسنده Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Poorsina street, Tehran, Iran. Neghabi-Hajiagha, Mahdieh , Aliahmadi، Atousa نويسنده Department of Biology, Medicinal Plants and Drug Research Institute, Shahid Beheshti University, Tehran, IR Iran , , Taheri، Mohammad Reza نويسنده Nanotechnology and Quantum Computing Laboratory, Shahid Beheshti University, GC, Tehran, Iran , , Ghassempour، Alireza نويسنده , , Irajian، Gholamreza نويسنده , , Rezadoost، Hassan نويسنده Department of Phytochemistry, Medicinal Plants and Drugs Research Institute , , Feizabadi، Mohammadmehdi نويسنده Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran Feizabadi, Mohammadmehdi
Background and Objectives: Due to the importance of finding of new antibacterial agents, the antibacterial properties of Prosopis cineraria aerial parts were investigated using a bioassay guided fractionation scheme.
Materials and Methods: The organic extract was prepared via maceration in methanol, followed by the fractionation using n-hexane and ethyl acetate. The MICs of fractions were determined against some human pathogenic bacteria using broth micro-dilution assay. The primary characterization and identification of bioactive substance(s) was based on a bio-autograph- ical method using HPTLC and flash chromatography in parallel with agar overlay assays. Finally the exact mass of effective compound(s) was determined by LC-MS.
Results: The best antibacterial activities were related to the ethyl acetate fraction. The effective antibacterial compound of the plant were 2 substances with molecular weight of 348 and 184 Dalton that inhibited the growth of assessed Gram positive bacteria with MIC values lower than 125 to 62.5 µg/ml synergistically.
Conclusion: Further analysis using nuclear magnetic resonance could reveal the exact structure of these two antibacterial substances. These 2 effective antibacterial compounds could be applied as lead compound for synthesis of new antibacterial agents.