2003 年 2003 巻 Suppl3 号 p. 325-329
Aspergillus Section flavi populations, natural and in vitro aflatoxin (AF) production in dried Cavendish bananas (Musa cavendishii), a major agricultural commodity in Southern Philippines, were evaluated. Aspergillus Section flavi was isolated from fresh and dried Cavendish bananas, food-contact surfaces, and the air surrounding the production area. Isolates were identified to be Aspergillus flavus based on spore type and conidial structure. Of 20 Aspergillus Section flavi isolates tested, 8 (40 %) produced AFB1+AFB2 ranging from 1 μg/kg to 16 mg/kg in rice, Cavendish banana and Yeast Extract Sucrose medium. Six (75 %) of the 8 isolates produced >20μg/kg total AF which is the Philippine regulatory limit for AF in food and processed peanut products. No AF was detected in 65 samples of dried Cavendish bananas. The possible role of competitive microorganisms and microbial metabolites is presented to explain the low incidence of AF in dried Cavendish bananas. With this research, we ascertained that Cavendish banana is suitable as substrate for growth and AF production by Aspergillus Section flavi. Although AF levels in the commodity may be negligible, the development and application of measures to control populations of fungi at all levels of production, particularly those that are mycotoxigenic, is vital to ensure safety of the commodity.
