Extraction, evaluation and structure elucidation of bioactive metabolites of lactobacillus helveticus cnrz 32

Abstract

There is no previous work that utilizes the multi-solvent extraction and structure elucidation of Lactobacillus helveticus cell-free supernatant (CFS). In this study, the CFS of Lb. helveticus CNRZ 32 was extracted by ethyl acetate, diethyl ether, dichloromethane, and n-hexane solvents. The extracts of considerable antimicrobial activities were characterized through GC/MS clarify metabolic profiles, TLC for compounds separation, and bio-autography to determine the number and Rf of effective compounds. Ethyl acetate extract possessed the strongest effect on all tested pathogens with inhibition diameter reached 38 mm in the case of Staphylococcus sciuri, while Diethyl ether and Dichloromethane extracts came secondly. The extract of Ethyl acetate mainly included butyl lactate with area % (59.45), while 9,12-Octadecadienoic acid (Z,Z)-, methyl ester and different health beneficial compounds were identified in both Diethyl ether and Dichloromethane extracts. Due to the strong synergism among Chitosan Nanoparticles and different extracts, the MIC values were lowered by about 20 – 50%.