Fagopyrum tataricum is used for the treatment of type 2 diabetes mellitus in Taiwan. The aim of this study was to evaluate the inhibitory effects of 75 % ethanol extract of buckwheat (EEB) and rutin on carbohydrate-metabolized enzymes, including α-amylase and α-glucosidase, which are related to hyperglycemia. The rutin dosage (40 μg/mL) was equivalent to that of EEB (200 μg/mL). In addition, the antioxidant and antiglycation activities of EEB and rutin were investigated. Results showed that both EEB and rutin exerted free radical (DPPH and ABTS) scavenging activity. They also attenuated protein glycation to lower the generation of advanced glycation end-products (AGEs) through the suppression of fructosamine and α-dicarbonyl compounds. Moreover, EEB and rutin also inhibited α-amylase and α-glucosidase activity. Taken together, these findings suggest that EEB and rutin may reduce oxidative stress, AGEs formation, and carbohydrate-metabolized enzymes hence EEB may use as protection agent in diabetic patients.

Amyloid-beta (Abeta) protein is a key factor in the pathogenesis of Alzheimer's disease (AD). Moreover, it has been reported that oxidative stress is involved in the biochemical pathway by which Abeta can lead to neuronal dysfunction. Recently, docosahexaenoic acid (DHA; C22:6) and eicosapentaenoic acid (EPA; C20:5n-3) have been reported to protect against AD. However, these omega-3 fatty acids are frequently obtained from fish oil and may contain heavy metals. In this study, we utilized Nannochloropsis oceanica to produce omega-3 fatty acid. We observed that when urea levels (nitrogen source) were lowered from 2 to 0.2 g/L in Nannochloropsis oceanica cultures, EPA production increased. Moreover, EPA in Nannochloropsis oceanica effectively promoted antioxidant activity to counter the Abetainduced oxidative stress in Neuro-2A cells. These results indicate that Nannochloropsis oceanica may be potentially used as a therapeutic agent or as a functional food that promotes protection against AD.