Natural microflora of prepeeled garlic and their resistance to garlic antimicrobial activity

Prepeeled garlic carried 10(6)-10(8) cfu g(-1) micro-organisms; 10(3)-10(5) times more than freshly peeled garlic. Scanning electron micrographs revea led the presence of various types of micro-organisms on the surface of the garlic. Fifty-one lactic acid bacteria, 40 non-lactic acid bacteria and 15 yeasts were isolated from prepeeled garlic with heterofermentative lactic a cid bacteria predominating among the lactic acid bacteria, and Leuconostoc occurring most frequently. Twenty-six isolates of lactic acid bacteria grow n in MRS broth with 20% garlic juice or higher were extremely resistant to garlic. Gram negative rod-shaped bacteria were the most frequently occurrin g non-lactic acid bacteria, with a predominance of the general Pseudomonas and Enterobacter. Cryptococcus neoformans was the only species of yeast iso lated The inhibitory action of methyl methanethiosulfonate, but not of iodo acetate, appeared similar to that of garlic. (C) 1999 Academic Press.