成团泛菌胞外多糖吸湿保湿和抗辐射活性

成团泛菌KFS发酵产胞外多糖(EPS)是由葡萄糖和甘露糖组成的均一性杂多糖,重均分子量约为756kDa。以透明质酸和甘油为对照,分别在2种相对湿度环境下考察了EPS的吸湿性和保湿性。基于该EPS较强的抗氧化活性,进一步考察了其对不同菌体的抗辐射保护作用。结果表明:在相对湿度43%和81%的环境中,EPS均显示出较好的保湿活性,吸湿性与透明质酸相似,略低于甘油;EPS对菌体的辐射保护作用与糖溶液浓度和紫外辐照时间呈相关性,当糖溶液浓度为4 mg/mL、紫外辐照5 min时,大肠杆菌、白色念球菌以及金黄色葡萄球菌的存活率分别是48.49%、36.73%、47.5%,明显高于空白对照组的13.68%、13.47%和12.25%。所以,EPS作为天然的保湿剂和抗辐射剂有应用前景。

Role of p53 in Anticancer Drug Treatment- and Radiation-Induced Injury in Normal Small Intestine

In the human gastrointestinal tract,the functional mucosa of the small intestine has the highest capacity for absorption of nutrients and rapid proliferation rates,making it vulnerable to chemoradiotherapy.Recent understanding of the protective role of p53- mediated cell cycle arrest in the small intestinal mucosa has led researchers to explore new avenues to mitigate mucosal injury during cancer treatment.A traditional p53 inhibitor and two other molecules that exhibit strong protective effects on normal small intestinal epithelium during anticancer drug treatment and radiation therapy are introduced in this work.The objective of this review was to update current knowledge regarding potential mechanisms and targets that inhibit the side effects induced by chemoradiotherapy.