Antibacterial and Anticandidal Effect of Aqueous Extract of Garlic on the Growth of Mixed Cultures and the Anticandidal and Platelet Activity of Commercial Preparations of Garlic

Abstract

The effect of Lactobacillus acidophilus on the growth of Candida albicans and Escherichia col i was investigated in the presence of aqueous extract of garlic. L. acidophilus, a homofermentative organism, produced lactic acid that lowered the pH of the culture medium, resulting in a reduction in numbers of C. albicans and E. coli in mixed culture. When the extract of garlic was added at a concentration of 2.56 mg total thiosulphinate/ml for C. albicans in mixed culture and at a concentration of 5.12 mg total thiosulphinate/ml for E. coli in mixed culture, the reduction in cell numbers of both C. albicans and E. coli was accelerated. After 4 h no C. albicans cells were countable, while E. coli cells were absent after 24 h. Several commercial preparations of garlic, which included oil macerates, pastes, tablets and powders, were examined for their anticandidal activity and for their ability to inhibit platelet aggregation. The activity of the preparations was assayed by determining the concentration of total thiosulphinates present in each brand. Only the garlic tablet formulation exhibited good anticandidal and antiplatelet activity, whereas all the other preparations possessed virtually no anticandidal and antiplatelet properties. Key words: anticandidal, antiplatelet, aqueous extract of garlic, microbial flora, probiotic, mixed culture, commercial preparations of garlic.