Scavenging ABTS Free Radicals Research Articles

Scoparone from Artemisia capillaris Thunb. induces apoptosis in HepG2 cells via activation of both intracellular and extracellular pathways

Six separated compounds were identified from Artemisia capillaris Thunb., and they were 7-methoxycoumarin (1), 6,7-dimethoxycoumarin (2), 7-hydroxy-6-methoxycoumarin (3), quercetin (4), chlorogenic acid (5) and caffeic acid (6). Among them, 6,7-dimethoxycoumarin, as known as scoparone, was the most effective on scavenging ABTS free radicals (IC50 = 0.97 μΜ) and was then tested by cytotoxic activity and pro-apoptotic activity against HepG2 cells. Scoparone dose-dependently and time-dependently inhibited the cell proliferation. Furthermore, scoparone induced the expression of Bax, concurrently suppressing the expression of Bcl-2, resulting in a noteworthy elevation in the Bax/Bcl-2 ratio to up-regulate Caspase-3 activity, thus inducing cell apoptosis via the intracellular pathway. Meanwhile, scoparone promoted the expression of Fas, FasL, FADD, Caspase-8 and Caspase-3, indicating that scoparone also triggered apoptosis via the extracellular pathway. In a word, scoparone demonstrated remarkable antitumor capability to induce apoptosis of HepG2 cells through both intracellular and extracellular pathways.

Effect of Drying Temperature on Quality of Purple Sweet Potato Powder

In order to reveal the effect of drying temperature on quality of purple sweet potato powder, four drying temperatures (70, 80, 90 and 100 oC) were selected. The effect of color, anthocyanin content, and scavenging ABTS free radical ability were studied. The results showed that drying process decreased anthocyanin content, and with increasing drying temperature, the a* value and anthocyanin content decreased. However, the treatments dried at 80, 90 oC exhibited the similar scavenging ABTS free radical ability with control, while the treatments dried at 70, 100 oC had lower scavenging ability than control.