Comparative phytochemical analysis and bioactive potential of white and black garlic

The phenolic and organosulfur compound profiles of black garlic samples produced at different temperatures, humidity and durations were determined using liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) and their bioactive properties were compared with those of the white garlic samples. The total concentrations of the phenolic compounds in the white (fresh) garlic samples were observed at 24.15 mg/kg and it was found that caffeic and ferulic acids, epicatechin, apigenin and p-hydroxybenzoic acid were dominant. Resveratrol, which is present in trace amounts in fresh garlic, has shown a significant increase in black garlic. Allicin was found to be the predominant organosulfur compound in white garlic, whereas S-allyl-L-cysteine was dominant in black garlic. Antimicrobial activity and minimum inhibitory concentration of the garlic samples were evaluated on two test microorganisms (Staphylococcus auereus and Escherichia coli). The effects of the garlic extracts on cancer cell lines (A549, HuH-7, MCF-7, HCT-116) were also assessed. The anticancer effect of the black garlic extracts was observed at higher concentrations than the white garlic water extracts, but the white garlic and black garlic methanolic extracts were effective on all cancer cell lines within the concentration range used in the study.