Peanuts are important oil and food sources worldwide and can be easily contaminated by highly toxic aflatoxins （AFs） , which often exist in peanuts and related foodstuff. In this experiment, a total of 12 A. flavu...Peanuts are important oil and food sources worldwide and can be easily contaminated by highly toxic aflatoxins （AFs） , which often exist in peanuts and related foodstuff. In this experiment, a total of 12 A. flavus strains were isolated from soil collected from 7 cities of China and the aflatoxin con-tamination levels in peanuts in these areas were detected to find out the relationship between aflatoxin contamination level and amount of soil isolates in the same region, as well as the correlation between cli-mate type and peanut aflatoxin contamination level. In this study, we found that in high - temperature and moist areas, toxin producing strains were easier to be isolated and the aflatoxin contamination level in peanuts was higher. We also studied the association between the aflR expression determined by fluorogen- ic quantitative PCR and the aflatoxin production. The results showed all 3 atoxigenic isolates had the same cycle threshold 21. 38, suggesting that atoxigenic strains had the same expression of aflR, which was the key gene of aflatoxin production.展开更多
Investigation on fungal populations and mycotoxins of mouldy rapeseed was conducted in this paper. A total of 578 rapeseed samples were collected from 11 Chinese provinces in 2015, and 141 samples were contaminted by ...Investigation on fungal populations and mycotoxins of mouldy rapeseed was conducted in this paper. A total of 578 rapeseed samples were collected from 11 Chinese provinces in 2015, and 141 samples were contaminted by mycete. Mouldy rapeseed samples with exceeding specified standard were found in all areas. The highest percentages of samples were from Hunan, Jiangxi and Hubei provinces with above standard rate of 31.91%, 24.54% and 20.45% respectively. Mycete in 29 severely mouldy samples were isolatedand determined by using dilution method. Eighty-three dominant isolates were found,among which fungal strain number ranged from 1 to 8. Aspergillus flavus, Penicillium steckii and Penicillium citrinum were dominant myco-populations identified by morphological and molecular biological methods. Rapeseed from the Southern provinces including Jiangxi,Hunan and Guangxi were contaminated by more isolates. Mycotoxins content were evaluated by LC–MS/MS. AFB1, BEA and FB1 were the top 3 prevalent mycotoxins. BEA and FB1 contaminations in rapeseed were relatively low. This investigation provid support for protecting public health and ensuring consumption security of rapeseed.展开更多
文摘Peanuts are important oil and food sources worldwide and can be easily contaminated by highly toxic aflatoxins （AFs） , which often exist in peanuts and related foodstuff. In this experiment, a total of 12 A. flavus strains were isolated from soil collected from 7 cities of China and the aflatoxin con-tamination levels in peanuts in these areas were detected to find out the relationship between aflatoxin contamination level and amount of soil isolates in the same region, as well as the correlation between cli-mate type and peanut aflatoxin contamination level. In this study, we found that in high - temperature and moist areas, toxin producing strains were easier to be isolated and the aflatoxin contamination level in peanuts was higher. We also studied the association between the aflR expression determined by fluorogen- ic quantitative PCR and the aflatoxin production. The results showed all 3 atoxigenic isolates had the same cycle threshold 21. 38, suggesting that atoxigenic strains had the same expression of aflR, which was the key gene of aflatoxin production.
文摘Investigation on fungal populations and mycotoxins of mouldy rapeseed was conducted in this paper. A total of 578 rapeseed samples were collected from 11 Chinese provinces in 2015, and 141 samples were contaminted by mycete. Mouldy rapeseed samples with exceeding specified standard were found in all areas. The highest percentages of samples were from Hunan, Jiangxi and Hubei provinces with above standard rate of 31.91%, 24.54% and 20.45% respectively. Mycete in 29 severely mouldy samples were isolatedand determined by using dilution method. Eighty-three dominant isolates were found,among which fungal strain number ranged from 1 to 8. Aspergillus flavus, Penicillium steckii and Penicillium citrinum were dominant myco-populations identified by morphological and molecular biological methods. Rapeseed from the Southern provinces including Jiangxi,Hunan and Guangxi were contaminated by more isolates. Mycotoxins content were evaluated by LC–MS/MS. AFB1, BEA and FB1 were the top 3 prevalent mycotoxins. BEA and FB1 contaminations in rapeseed were relatively low. This investigation provid support for protecting public health and ensuring consumption security of rapeseed.
