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Fermented Korean soybean foodstuffs(12 samples of meju, 28 samples of doenjang and 28 samples of kanjang) which collected nation wide in Korea, were used to isolate of fungi. And the fungi producing ochratoxin A(OA) among isolated fungi were identified. Of total 222 fungi isolated in each samples, the production rate of OA was 17.7%(39/222). Four fungi out of 39 isolates which production OA showed a higher amount of ochratoxin A. From these results, four kinds of fungi producing large quantities of OA were Penicillium spp., Phialotubus microsporus, Eupenicillium lapidosum, and Paecilomyces variotti, respectively. Four fungi showed the optimum growth at water activity(a_w) of 0.99, but production of OA was almost inhibited at aw, of 0.85. Furthermore, three fungi except P. variotti showed the optimum growth at 30℃, while OA production inhibited at same temperature. The optimal pH for toxin production except P. variotti was 6.5. Also, toxin production was not greatly influenced by pH.
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