膳食营养剂对灰褐牛肝菌中镉的生物可给性及其健康风险的影响

Effects of Dietary Nutrients on Bioaccessibility and Health Risk of Cadmium in Boletus griseus

聚焦灰褐牛肝菌(Boletus griseus)富镉(Cd)问题,调研了云南3个地区B.griseus样本中的总Cd含量,选取了高、中、低3种不同Cd含量B.griseus样本,建立了一种更易实现、更易量化的体外全仿生消化方法,评价了B.griseus中镉的生物可给性(Cd-BAc),研究了单宁酸、CaCl2、原花青素、葡萄糖酸锌钙、红毛丹果皮多酚5种膳食营养成分对Cd-BAc的影响,并以此为基础评价了B.griseus中Cd的食用健康风险。结果表明,采集的53个B.griseus样本均具有较高的总Cd含量,在胃部的Cd-BAc为55.30%~59.36%,但是小肠的弱碱近中性环境显著降低了B.griseus中Cd的溶出,Cd-BAc为39.59%~52.86%,大肠菌群发酵进一步降低Cd-BAc至21.41%~25.28%。5种膳食营养剂在胃部对Cd-BAc影响不大,在小肠部和大肠菌群发酵中,均显著降低了Cd-BAc, CaCl2效果最为显著。以B.griseus中Cd总量计,摄食中镉、高镉含量的B.griseus,Cd对人体的风险熵为2.98和5.13;综合考虑Cd-BAc以及5种膳食营养剂的影响,其风险熵可降低至0~0.37。研究结果表明,B.griseus中Cd的食用健康风险很高,膳食营养剂可通过降低肠道Cd-BAc而调控其对人体的健康风险,因此,膳食营养剂可能是控制高镉食品健康风险的一种有效策略,但是该策略的有效性需要进一步的体内实验验证。

Focus on the problem of cadmium(Cd)enrichment in Boletus griseus,total Cd content in the B.griseus samples from three regions in Yunnan was investigated,and three B.griseus with different Cd contents(high,medium,and low)were selected to evaluated the bioaccessibility of Cd(Cd-BAc)in B.griseus by a more realizable and quantifiable in vitro whole biomimetic digestive method established in this study.The effects of five dietary nutrients,tannic acid,CaCl 2,proanthocyanins,Zn/Ca gluconate and rambutan peel polyphenols,on Cd-BAc were studied,and the edible health risk of Cd in B.griseus was assessed based on total Cd contents and Cd-BAc.The results showed that there were high Cd contents in 53 B.griseus samples.The Cd-BAc during the gastric digestion was 55.30%-59.36%.The Cd-BAc was decreased to 39.59%-52.86%due to significantly reduced dissolution in the weakly alkaline and nearly neutral environment of the small intestine.The Cd-BAc was further decreased to 21.41%-25.28%by large intestinal flora fermentation.The five dietary nutrients had little effects on Cd-BAc during the gastric digestion,but significantly reduced Cd-BAc during the small and large intestinal flora fermentation,of which CaCl 2 was the most effective.Based on the total Cd contents in B.griseus,the human Cd exposure risk hazard quotient(HQ)caused by medium Cd and high Cd content of B.griseus was 2.98 and 5.13,but considering Cd-BAc and the effects of five dietary nutrients,the HQ could be reduced to 0-0.37.The result indicated that the edible health risk of Cd in B.griseus was very high,and dietary nutrients could modulate its health risk to human by reducing its bioaccessibility in intestine.Therefore,dietary nutrients might be an effective strategy to control the health risks of Cd during the processing or consumption of foods with high Cd content.However,the effectiveness of this strategy requires further in vivo experimental verification.