Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiologi...Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiological level, fungal and mycotoxin contaminations of local foodstuffs in Cixian County were analyzed using classical fungal culture methods and HPLC. From 1990 to 1994, 220 corn/wheat samples and 34 corn samples were studied. As a control, 26 corn samples collected from a relatively low incidence area of Eca in Zanhuang County were analyzed for mycotoxins in 1990. The results showed that fungal contamination in corn and wheat was severe and that several of the predominant contaminating fungi such as Furasium moniliforme, etc. were carcinogenic. HPLC results showed that the detection rate and mean content of the mycotoxin sterigmatocystin (ST) in the mountainous area (5/8; 9. 14 μg/kg) were significantly higher than those in the hilly (0; 0) and plain areas (1/18; 1. 29 μg/kg) as well as in low risk area control samples (3/26; 0. 76 μg/kg). Detection rates of deoxynivalenol (DON) in mountainous and hilly areas (5/8, 4/8 respectively) were slightly higher than that in plain area (8/18), while the mean content of DON in the plain area was significantly higher (90. 45-170. 22 vs 50. 56 and 46. 45 μg/kg).Among the different aflatoxins, AFB1 was detected in samples from the two villages in the plain area for the subsequent two years. The mean content of AFB1 was 0. 0183μg/kg, and the highest level was 0. 0497 μg/kg. No AFB1 was detected in the samples from mountainous and hilly areas. AFG1 was detected in more than half of all the samples, and its concentration ranged from 8. 77 to 46. 51 ng/kg. No AFG2 was found in the samples. Thus, the results suggest that at present, fungal and mycotoxin contamination of foodstuffs in Cixian County are quite common.展开更多
Fungi play a significant role in biology-related domains, and with the molecular biology technology advancing, identification of fungi at molecular level and verification of genetic transformant has become the necessa...Fungi play a significant role in biology-related domains, and with the molecular biology technology advancing, identification of fungi at molecular level and verification of genetic transformant has become the necessary step of test. By far, however, there is no ideal high-throughput molecular identification method. In this paper, a high-throughput device was designed, and a novel PCR-mediated molecular identification method suitable for the device was developed. Through cloning of ccllulase encoding genes and regulatory genes on the genome of Trichoderma reesei, cloning of promoter of phesphoglycerate kinase gene 1 and xylanase encoding genes on the genome and expression vector of Saccharomyces cerevisiae, and ITS sequences cloning and RAPD analysis of T. reesei, S. cerevisiae, Penicil- lium oxalicum, Rhizopus stolonifer, Aspergillus niger, A. carbonarius and A. japonicas, the method turned out to be an effective one with wide application potential. The establishment of the method has worked out the bottleneck of high-throughput molecular identification.展开更多
Background and Objective Lung cancer, which threatens human’s health and life, is the malignant tumor with the most rapid increase of morbidity. Although recent years the basic
文摘Fungal and mycotoxin contamination has been found in fordstuffs from Cixian County, an area with a high incidence of esophageal carcinoma (Eca). To set a scientific foundation for the prevention of Eca at the etiological level, fungal and mycotoxin contaminations of local foodstuffs in Cixian County were analyzed using classical fungal culture methods and HPLC. From 1990 to 1994, 220 corn/wheat samples and 34 corn samples were studied. As a control, 26 corn samples collected from a relatively low incidence area of Eca in Zanhuang County were analyzed for mycotoxins in 1990. The results showed that fungal contamination in corn and wheat was severe and that several of the predominant contaminating fungi such as Furasium moniliforme, etc. were carcinogenic. HPLC results showed that the detection rate and mean content of the mycotoxin sterigmatocystin (ST) in the mountainous area (5/8; 9. 14 μg/kg) were significantly higher than those in the hilly (0; 0) and plain areas (1/18; 1. 29 μg/kg) as well as in low risk area control samples (3/26; 0. 76 μg/kg). Detection rates of deoxynivalenol (DON) in mountainous and hilly areas (5/8, 4/8 respectively) were slightly higher than that in plain area (8/18), while the mean content of DON in the plain area was significantly higher (90. 45-170. 22 vs 50. 56 and 46. 45 μg/kg).Among the different aflatoxins, AFB1 was detected in samples from the two villages in the plain area for the subsequent two years. The mean content of AFB1 was 0. 0183μg/kg, and the highest level was 0. 0497 μg/kg. No AFB1 was detected in the samples from mountainous and hilly areas. AFG1 was detected in more than half of all the samples, and its concentration ranged from 8. 77 to 46. 51 ng/kg. No AFG2 was found in the samples. Thus, the results suggest that at present, fungal and mycotoxin contamination of foodstuffs in Cixian County are quite common.
基金Supported by Applied Fundamental Research Project of Guangxi Department of Science and Technology(14125008-2-13)
文摘Fungi play a significant role in biology-related domains, and with the molecular biology technology advancing, identification of fungi at molecular level and verification of genetic transformant has become the necessary step of test. By far, however, there is no ideal high-throughput molecular identification method. In this paper, a high-throughput device was designed, and a novel PCR-mediated molecular identification method suitable for the device was developed. Through cloning of ccllulase encoding genes and regulatory genes on the genome of Trichoderma reesei, cloning of promoter of phesphoglycerate kinase gene 1 and xylanase encoding genes on the genome and expression vector of Saccharomyces cerevisiae, and ITS sequences cloning and RAPD analysis of T. reesei, S. cerevisiae, Penicil- lium oxalicum, Rhizopus stolonifer, Aspergillus niger, A. carbonarius and A. japonicas, the method turned out to be an effective one with wide application potential. The establishment of the method has worked out the bottleneck of high-throughput molecular identification.
基金supported by a grant from the key project of the National Natural Science Foundation of China (to Qinghua ZHOU) (No. 30430300)National Natural Science Foundation of China (to Qinghua ZHOU) (No. 30670922)
文摘Background and Objective Lung cancer, which threatens human’s health and life, is the malignant tumor with the most rapid increase of morbidity. Although recent years the basic
