A rapid identification method for aflatoxin-producing strains ofAspergillus flavus andA. parasiticus by ammonia vapor
- 238 Downloads
The colony reverse of aflatoxin (AF)-producing strains ofAspergillus flavus andA. parasiticus turned pink when their cultures were exposed to ammonia vapor. The color change was visible for colonies grown on media suitable for AF production such as potato dextrose, coconut, and yeast extract sucrose agars after 2 d incubation at 25°C. Of the 120 strains ofA. flavus, A. parasiticus, and two related species inA. flavus group:A. oryzae andA. sojae tested in this study, only the AF-producing strains ofA. flavus andA. parasiticus showed the pink pigmentation. The color change occurred immediately after the colony was contacted with ammonia vapor. This method was useful for rapid screening the AF-producing strains ofA. flavus andA. parasiticus.
Key Wordsaflatoxin-producing strains ammonia vapor Aspergillus flavus screening method
Unable to display preview. Download preview PDF.
- Abdollani, A. and Buchanan, R. I. 1981a. Regulation of aflatoxin biosynthesis: characterization of glucose as an apparent inducer of aflatoxin production. J. Food Sci.46: 143–146.Google Scholar
- Abdollani, A. and Buchanan, R. I. 1981b. Regulation of aflatoxin biosynthesis: induction of aflatoxin productivity by various carbohydrates. J. Food Sci.46: 633–635.Google Scholar
- Beuchat, L. R. 1984. Comparison ofAspergillus differential medium andAspergillus flavus/parasiticus agar for enumerating total yeasts and molds and potentially aflatoxigenic aspergilli in peanuts, corn meal and cowpeas. J. Food Protect.47: 512–519.Google Scholar
- Diener, U. L. and Davis, N. D. 1967. Limiting temperature and relative humidity for growth and production of aflatoxin and free fatty acids byAspergillus flavus in sterile peanuts. J. Am. Oil Chemsits' Soc.44: 259–263.Google Scholar
- Diener, U. L. and Davis, N. D. 1969. Aflatoxin formation byAspergillus flavus In: Aflatoxin, (ed. by Goldblatt, L. A.), pp. 13–54. Academic Press, New York.Google Scholar
- Hatsuda, Y., Kuyama, S. and Terashima, N. 1955. Studies on the metabolic products ofAspergillus versicolor. Part 3. The physical and chemical properties and the chemical structure of versicolorin. J. Agr. Chem. Soc. Japan29: 11–20, (in Japanes.)Google Scholar
- Heathcote, J. G. and Hibbert, J. R. 1978. Production of aflatoxins. In: Aflatoxins: Chemical and biological aspects, (ed. by Heathcote, J. G. and Hibbert, J. R.), pp. 16–29. Elsevier, Amsterdam.Google Scholar
- Minamisawa, M., Sugimoto, T. and Kino, N. 1980. The cleanup method of aflatoxin extracts by using Sep-pac silica cartridge. Proc. Jpn. Assoc. Mycotoxicol.11: 23–27 (In Japanese.)Google Scholar
- Saito, M., Kawasugi, K., Siriacha, P., Tsuruta, O., Buangsuwon, D., Goto, T., Manabe, M. and Panawas, K. 1986. Distribution ofAspergillus flavus in the maize fields and drying facilities in Thailand: An examination in dry season (January–February, 1986). Proc. Jpn. Assoc. Mycotoxicol.24: 35–39.Google Scholar
- Saito, M., Tsuruta, O., Siriacha, P., Kawasugi, S. and Manabe, M. 1989. Atypical strains ofAspergillus flavus isolated in maize field—Aflatoxin-producing ability and distribution in Thailand. JARQ23: 151–154.Google Scholar
- Tsuruta, O. 1990. Collection of food-invading fungi from subtropical regions of Japan. In: Ann. rept. exploration and introduction of microbial genetic resources, pp. 29–37. Nat. Inst. Agrobiol. Resources, Tsukuba. (In Japanese.)Google Scholar