Investigation of the effect of extraction methods to the antimicrobial activity of plants

The purpose of this study is to investigate the effects of different extraction methods (agitation, maceration and soxhlet) on the antimicrobial activity of plants. Zingiberaceae family, which has medicinal and aromatic properties, has been studied with three different rhizomes ginger (Zingiber officinale), galangal (Alpinia officinarum) and turmeric (Curcuma longa). The extracts of plant samples were prepared by 70% ethanol for agitation and maceration, and by petroleum ether, n-hexane, chloroform, acetone, methanol and water for the soxhlet. These extracts have been tested against 18 different microorganisms (Bacillus subtilis DSMZ 1971, Enterobacter aerogenes ATCC 13048, Enterococcus faecalis ATCC 29212, Enterococcus faecium, Escherichia coli ATCC 25922, Klebsiella pneumoniae, Pseudomonas aeruginosa DSMZ 50071, Pseudomonas fluorescens P1, Salmonella enteritidis ATCC 13075, Salmonella infantis, Salmonella kentucky, Salmonella typhimurium SL 1344, Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis DSMZ 20044, Listeria innocula, Listeria monocytogenes, Enterococcus durans and Candida albicans DSMZ 1386) In this study, minimum inhibitory concentration (MIC) and minimum bactericidal/fungicial concenration (MBC/MFC) methods were used. Obtained results; clearly demonstrates how the method of extracting active ingredients from plant samples changes the activity. For this reason, it is important to use more than one extraction method instead of extraction by a single method in any research related to the anti-infective properties of plant-derived compounds.