Effect of gamma radiation on the inactivation of aflatoxin B1 in food and feed crops

Abstract

Samples of food crops (peanut, peeled pistachio, unpeeled pistachio, rice, and corn) and feed (barley, bran, corn) were autoclave-sterilized, and inoculated with 10 6 of spore suspension of an isolate of Aspergillus flavus fungus known to produce aflatoxin B1 (AFB1) . Following a 10-day period of incubation at 27 C to allow for fungal growth, food and feed samples were irradiated with gamma radiation at the doses 4, 6, and 10 kGy. Results indicated that degradation of AFB1 was positively correlated with the increase in the applied dose of gamma ray for each tested sample. At a dose of 10 kGy percentages of AFB1 degradation reached highest values at 58.6, 68.8, 84.6, 81.1 and 87.8% for peanuts, peeled pistachios, unpeeled pistachios, corn and rice samples, respectively. In feed samples percentages of AFB1 degradation were 45, 66, and 90% in barley, 47, 75, and 86% in bran, and 31, 72, and 84% in corn for the doses of 4, 6, and 10 kGy, respectively. AFB1 degradation in food samples correlated negatively with oil content in irradiated samples. Thus, in peanuts, which contained the highest oil content, percentage of AFB1 degradation at 10 kGy was not more than 56.6%, whereas, the corresponding value in corn, which contained the lowest oil content, reached as high as 80%. The above results indicate the possibility of using gamma radiation as a means of degradation of AFB1 in food and feed crops to levels lower than the maximum allowed levels.

Effect of gamma radiation on reduction of mycotoxins in black pepper

“…However, there was no reduction in the mycotoxin content at doses less than 10 kGy. In agreement with our results, Ghanem, Orfi, and Shamma (2008) reported that degradation of AFB 1 in food crops (peanut, peeled pistachio, unpeeled pistachio, rice, and corn) and feed (barley, bran, corn) was positively correlated with increases in the applied dose of gamma ray. In a related study, doses of 15, 20, 25 and 30 kGy were used to destroy aflatoxin B 1 in peanut sample by 55-74% (Prado et al, 2003).…”

Immobilized Saccharomyces cerevisiae as a potential aflatoxin decontaminating agent in pistachio nuts

“…Other decontamination approaches include food and feed processing, such as thermal inactivation, irradiation, solvent extraction, mechanical separation, density segregation, and reduction in bioavailable aflatoxin by selective chemisorptions. Although such treatments almost completely reduce mycotoxin concentrations, these chemicals also reduce nutrient concentrations (4,9,15). Evidently, the best decontaminant should be detoxification by biodegradation, which might remove mycotoxins under mild conditions.…”

Aflatoxin in Agricultural Commodities and Herbal Medicine

“…The aflatoxin reduction in coffee bean during roasting was also found to be dependent on the type and temperature of roasting with moderate reductions of approximately 42 to 56% (Bullerman & Bianchini, 2007). Gamma irradiation was also reported to decrease the total aflatoxins and aflatoxin B 1 levels gradually, with increase in gamma irradiation dose from 0 to 10 kGy (Ghanem, Orfi, & Shamma, 2008;Gupta, Bajpai, Mishra, Saxena, & Singh, 2009;Kumari, et al, 2009). However, in another study a 24-43% reduction in aflatoxin contamination was observed with irradiation at 60 kGY (Jalili, Jinap, & Noranizan, 2010).…”