肠道微生物对土壤中铜、锌、锰生物可给性的影响

为了更全面、准确地评价土壤中金属元素对人体的健康风险,研究土壤中金属元素在结肠阶段的生物可给性具有重要意义。通过采集我国一些地区的6种土壤,利用in vitro方法(PBET和SHIME联用)研究土壤中Cu、Zn、Mn在胃、小肠、结肠阶段的生物可给性。研究显示,土壤中Cu、Zn、Mn在胃阶段的生物可给性分别为23.8%~63.0%、21.2%~64.4%、11.7%~35.6%;从胃阶段到小肠阶段,土壤中Cu的生物可给性提高了0.4%~14.4%,而土壤中Zn在小肠阶段的生物可给性降低了6.7%~38.7%。结肠阶段,土壤中Cu、Zn、Mn的生物可给性分别为2.4%~12.9%、5.7%~18.7%、6.2%~18.9%,与小肠阶段相比,分别降低了21.7%~56.9%、0.4%~36.8%、4.5%~19.1%。结果表明,在肠道微生物存在的情况下,土壤中Cu、Zn、Mn在结肠阶段有较低的人体健康风险。

Effect of Human Gut Microbiota on Bioaccessibility of Soil Cu, Zn and Mn

It is significantly important to investigate the bioaccessibility of the metal elements in the colon phase in order to assess the human health risks of metal elements in the soil comprehensively and accurately. Six soil samples were collected from some sites of China, and the bioaccessibility of soil Cu, Zn and Mn in the gastric, small intestinal and colon phases were determined using the physiologically based extraction test (PBET) combined with simulator of human intestinal microbial ecosystem (SHIME) model. In the gastric phase, the bioaccessibility of Cu, Zn and Mn was 23.8%-63.0%, 21.2%-64.4%, 11.7%-35.6%, respectively. In comparison with the values of gastric phase, Cu bioaccessibility increased 0.4%-14.4%, but Zn bioaccessibility decreased 6.7%-38.7% in the small intestinal phase. The bioaccessibility of Cu, Zn and Mn was 2.4%-12.9%, 5.7%-18.7%, 6.2%-18.9% in the colon phase, individually, which diminished 21.7%-56.9%, 0.4%-36.8%, 4.5%-19.1% compared with these of the small intestinal phase, separately. It could be concluded that these three metal elements (Cu, Zn and Mn) had a lower human health risk in the colon phase with human gut micobiota.