Study On Antioxidant Andanticancer Activity Of Extracts From Defatted Wheat Germ

Wheat germ is one of the main byproducts of wheat-milling industry, and it is a rich source of many bioactive compounds, so study on wheat germ is meaningful. In this paper, antioxidant and anticancer activities of defatted wheat germ extracts (DWGE) were studied to provide theoretical support for the development and exploitation of wheat germ.The main sections in this study are as follows:The antioxidant potential of DWGE in vitro was measured firstly by the radical scavenging activity, the inhibition on linoleic acid peroxidation and reducing power. All the extracts showed the scavenging activities of DPPH and ABTS in a concentration-dependent manner significantly. Among the DWGE, 70% ethanol extract was excellent in scavenging DPPH radical while 100 % ethanol extract showed the highest ABTS radical scavenging activity. All the extracts could inhibit the linoleic acid peroxidation, 30% ethanol extract, 50% ethanol extract and 70% ethanol extract could prolong the induction period of autoxidation of linoleic acid significantly compared with aqueous extract and ethanol extract. All the extracts showed some degree of electron-donating capacity in a linear concentration-dependent manner. The reducing power of ethanol extract and 70% ethanol extract were superior to other three extracts. It was summarized from four assays that both 50% ethanol extract and 70% ethanol extract exhibited high antioxidant activities.The effect of DWGE on lipid metabolism and antioxidative capacity of high-fat diet fed mice was studied. 60 male C57BL/6 mice were divided into 6 groups randomly. The control group was fed with basal diet, and the other five groups were fed with high-fat diet, high-fat diet and 2% 50% ethanol extract, high-fat diet and 6% 50% ethanol extract, high-fat diet and 2% 70% ethanol extract and high-fat diet and 6% 70% ethanol extract, respectively. After 8 weeks feeding, the plasma lipid status, the activities of antioxidases and the contents of MDA in organs were examined. The results were as follows: compared with the control, high levels of dietary fat increased fat-mediated oxidative stress, the content of MDA and the levels of plasma lipid in high-fat diet groups. The supplement of DWGE could modulate lipid metabolism, decrease the effect of high-fat diet, increase the antioxidative capacity of high-fat diet fed mice. The inhibitory effect of DWGE on the growth and proliferation of human breast carcinoma cell line MDA-MB231 in vitro was observed. MDA-MB231 cell was incubated in vitro by cell biology technique. By the method of MTT, the inhibition of DWGE on the proliferation of MDA-MB231 cell were remarkable and existed in dose- and time-dependent manners. Aqueous extract showed higher antitumor activity than 30% ethanol extract.The morphological changes of MDA-MB231 cell treated with DWGE was investigated by light microscope and electron microscope. After treated with DWGE, MDA-MB231 cell showed typical apoptotic characteristics, such as cell shrinkage, cell volume reduction, the villus on the surface of MDA-MB231 cell disappeared, and the membrane was shrinkage to form apoptotic bodies, the typical apoptotic features was observed from the cell nucleus of MDA-MB231 cell by fluorescent microscopy, such as chromatin condensation, nuclear fragmentation.These results demonstrated DWGE possessed antioxidant activity, antilipemic action and antitumor capacity, and it is effective in the prevention of dyslipidemia, cardiovascular disease, aging and cancer. DWG could serve as a new source of natural antioxidants or nutraceuticals with potential applications to reducing the level of oxidative stress and related health benefits.