Lin Xiao-hui, Hu Xiao, Li Feng-qin
Key Lab Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Zhonghua Yu Fang Yi Xue Za Zhi. 2012 Oct;46(10):937-41.
To develop and validate an in vitro digestion model for assessing the bioaccessibilities of some important mycotoxins of aflatoxin B group (aflatoxin B(1) and aflatoxin B(2), AFB(1) and AFB(2)).
Using simulating gastrointestinal physiological digestion process, the effects of digestion time (long, medium and short), the fasting and feeding status (fasting, between fasting and semi-feeding, semi-feeding, between semi-feeding and feeding, feeding states), the volume and pH (high, medium and low) of digestive solution, as well as other food ingredients ingested along with aflatoxin B group from mixed foods on bioaccessiblities of AFB(1) and AFB(2) in the mouth, stomach and small intestine were studied. The optimal technical parameters of the model were identified and the model was validated with mycotoxin adsorbents.
The optimal conditions of AFB(1) releasing from the ingested foods at the highest concentration in gastrointestinal tract were as follows: digestion time of 6 min, 1.5 h and 2.5 h in mouth, stomach and duodenum, respectively; the optimal pH values of 1.1 and 7.5 for gastric juice and duodenal fluid; the volume of 7, 13, 12 and 6 ml for saliva, gastric juice, intestinal fluid and bile, respectively; the optimal conditions of AFB(2) releasing from the ingested foods at the highest concentration in gastrointestinal tract were as follows: digestion time of 6 min, 2.5 h and 2.5 h in mouth, stomach and duodenum, respectively; the optimal pH values of 1.1 and 7.8 for gastric juice and duodenal fluid; the volume of 5, 12, 13 and 6 ml for saliva, gastric juice, intestinal fluid and bile, respectively. The bioaccessibilities of both AFB(1) and AFB(2) were highest at the fasting state (83.1% and 89.3% respectively). The bioaccessibilities decreased with the increasing of stomach contents, but the changes in bioaccessibility were not significant when the stomach contents reached the semi-feeding state or more. From semi-feeding to feeding state, the biocessibilities of AFB(1) decreased from 72.8% to 71.5% and AFB(2) decreased from 78.3% to 76.9%. Chlorophyll and activated charcoal were the strongest absorbent in reducing the bioaccessibilities of AFB(1) and AFB(2), and the bioaccessibilities decreased to 0.8% and 1.3% respectively.
The in vitro digestion model developed in the present study is stable and reproducible, and meets the requirements for assessing the bioaccessibilities of AFB(1) and AFB(2) in foods.
建立并验证一种体外消化模型，用于评估黄曲霉毒素B族某些重要霉菌毒素（黄曲霉毒素B1和黄曲霉毒素B2，即AFB1和AFB2）的生物可及性。
利用模拟胃肠生理消化过程，研究消化时间（长、中、短）、禁食和进食状态（禁食、禁食与半进食之间、半进食、半进食与进食之间、进食状态）、消化液体积和pH值（高、中、低）以及与黄曲霉毒素B族一同从混合食物中摄入的其他食物成分对AFB1和AFB2在口腔、胃和小肠中生物可及性的影响。确定该模型的最佳技术参数，并用霉菌毒素吸附剂对模型进行验证。
AFB1在胃肠道中以最高浓度从摄入食物中释放的最佳条件如下：在口腔、胃和十二指肠中的消化时间分别为6分钟、1.5小时和2.5小时；胃液和十二指肠液的最佳pH值分别为1.1和7.5；唾液、胃液、肠液和胆汁的体积分别为7毫升、13毫升、12毫升和6毫升。AFB2在胃肠道中以最高浓度从摄入食物中释放的最佳条件如下：在口腔、胃和十二指肠中的消化时间分别为6分钟、2.5小时和2.5小时；胃液和十二指肠液的最佳pH值分别为1.1和7.8；唾液、胃液、肠液和胆汁的体积分别为5毫升、12毫升、13毫升和6毫升。AFB1和AFB2在禁食状态下的生物可及性均最高（分别为83.1%和89.3%）。生物可及性随胃内容物增加而降低，但当胃内容物达到半进食状态或更多时，生物可及性变化不显著。从半进食到进食状态，AFB1的生物可及性从72.8%降至71.5%，AFB2从78.3%降至76.9%。叶绿素和活性炭是降低AFB1和AFB2生物可及性的最强吸附剂，生物可及性分别降至0.8%和1.3%。
本研究建立的体外消化模型稳定且可重复，满足评估食品中AFB1和AFB2生物可及性的要求。
