The aims of this study are to investigate the antioxidant and antitumor activities of the water and ethanol extracts isolated from Chinese yam (Dioscorea opposite Thunb.) flesh (CYF) and peel (CYP) and the effective compounds. It was found that all peel portions have a better effect on reactive oxygen (ROS) scavenging assay than meat portions, especially for the water extract of Chinese yam peel (CYP-W). Its IC50 values for hydroxyl radical (OH•) scavenging assay (744.25 ± 3.46 μg/mL) and for 1,1-diphenyl-2-picrylhydrazyl scavenging assay (374.85 ± 6.78 μg/mL) were both lower than that of yam flesh (CYF-W). Furthermore, the antitumor property of yam peel was more effective than that of yam flesh (CYF-W) on mouse models, with tumor inhibition rates were 47.92% and 27.41% for Ehrlich Ascites Tumor (EAC) model and 40.44% and 24.22% for H22 hepatocarcinoma tumor (H22) model. Meanwhile, extracts of peel showed higher allantoin, total flavonoids, and total phenolics contents than extracts of flesh. In conclusion, this study demonstrated that CYP-W exerted better antitumor activity than flesh extracts and the scavenging ROS effects were also significantly higher in the CYP-W in vitro. Moreover, the data indicated that allantoin may play an important role on antioxidative and antitumor capacity in yam peel.

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The aim was to investigate chemical composition of different extracts prepared from hawthorn fruit using 80% ethanol, 80% methanol, 80% acetone and pure deionised water, and evaluate their antioxidant and anti-alpha-glucosidase activities. The highest alpha-glucosidase inhibitory activity was determined in 80% acetone extract, while the highest DPPH scavenge capacity and ferric reducing power both exhibited in deionised water extract. In the correlation analysis, polyphenols, triterpenoids, protocatechuic acid and epicatechin all contribute to the alpha-glucosidase inhibitory activity, while flavonoids, polyphenols, vanillic acid, gallic acid, catechin and chlorogenic acid all contribute to the antioxidant activity. By HPLC-MS, thirty six compounds were identified, and fifteen of them were found from hawthorn fruits for the first time. Our results would provide a good reference for the further study on the antidiabetes activity of hawthorn, and also support that deionised water extract has the potential to be used as ingredients of functional food products.

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The vasorelaxant effects of RC and THPviathe NO/cGMP pathway and calcium channel blockade in isolated rat thoracic aorta are explored.