Tartary buckwheat (Fagopyrum tataricum) is a healthy and nutritionally important food item. In this study, we investigated the hepatoprotective effects of 75% ethanol extracts from tartary buckwheat (EEB) against ethanol- and carbon tetrachloride (CCl₄ )-induced liver damage. EEB were administered to C57BL/6 mice (ethanol induction) and Sprague-Dawley (SD) rats (CCl₄ induction) for 4 and 8 consecutive weeks, respectively. The major active compounds, rutin and quercetin, were also administered to ethanol- and CCl₄-induced animals. EEB inhibited increase in serum aspartate transaminase (AST), alanine transaminase (ALT) and alkaline phosphatase (ALP) levels in the ethanol- and CCl₄-induced animals; similar effects were found after rutin and quercetin administration. Moreover, EEB elevated the antioxidant enzyme activities, including those of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and superoxide dismutase (SOD), and inhibited the levels of hepatic inflammation in the ethanol- and CCl₄-treated animals. This study suggests that EEB exerts hepatoprotection via promoting anti-oxidative and anti-inflammatory properties against oxidative liver damage.

Because of the high incidence of cardiovascular diseases in Asian countries, traditional fermented foods from Asia have been increasingly investigated for antiatherosclerotic effects. This study investigated the production of nattokinase, a serine fibrinolytic enzyme, in pigeon pea by Bacillus subtilis fermentation. B. subtilis 14714, B. subtilis 14715, B. subtilis 14716, and B. subtilis 14718 were employed to produce nattokinase. The highest nattokinase activity in pigeon pea was obtained using B. subtilis 14715 fermentation for 32 hours. In addition, the levels of antioxidants (phenolics and flavonoids) and angiotensin converting enzyme inhibitory activity were increased in B. subtilis 14715-fermented pigeon pea, compared with those in nonfermented pigeon pea. In an animal model, we found that both water extracts of pigeon pea (100 mg/kg body weight) and water extracts of B. subtilis-fermented pigeon pea (100 mg/kg body weight) significantly improved systolic blood pressure (21 mmHg) and diastolic blood pressure (30 mmHg) in spontaneously hypertensive rats. These results suggest that Bacillus-fermented pigeon pea has benefits for cardiovascular health and can be developed as a new dietary supplement or functional food that prevents hypertension.

Chronic inflammation has been linked to a wide range of progressive diseases, including cancer, neurological disease, metabolic disorder, and cardiovascular disease. Epidemiological studies have provided convincing evidence that natural dietary compounds, which humans consume as food, possess many biological activities, including chemopreventative activities against various chronic inflammatory diseases. Here, we investigated the effect of 50% ethanol extracts of pigeon pea, as well as its major component, cyanidin-3-monoglucoside, an anthocyanin, on DNA damage, the activity of antioxidant enzymes, and free radical scavenging capacity in hydrogen peroxide (H₂O₂)-treated RAW264.7 macrophages. High-pressure liquid chromatography results indicated that 2 mg of the 50% ethanol extracts of pigeon pea contained 45 μg of cyanidin-3-monoglucoside. A comet assay indicated that 50% ethanol extracts of pigeon pea (2 mg mL⁻¹) and of cyanidin-3-monoglucoside (10 μM) protected RAW264.7 cells from DNA damage induced by a 24 h H₂O₂ treatment. These results can be attributed to the prevention of reduction in antioxidant enzyme activity and lipid peroxidation in H₂O₂-treated murine RAW264.7 macrophages by the 50% ethanol extracts of pigeon pea. Moreover, as there is an active interplay between oxidative stress and inflammation, we also evaluated the anti-inflammatory activity of the 50% ethanol extracts of pigeon pea and cyanidin-3-monoglucoside in lipopolysaccharide-treated RAW264.7 macrophages. We found that the 50% ethanol extracts of pigeon pea and of cyanidin-3-monoglucoside suppressed the production of inflammatory cytokines, including TNF-α, IL-1β, and IL-6, in these macrophages. These results imply that pigeon pea could be developed as a functional food by the food industry, or could be utilized for the commercial production of anthocyanins as antioxidants.

Fagopyrum tataricum(buckwheat) is used for the treatment of type 2 diabetes mellitus in Taiwan. This study was to evaluate the antihyperglycemic and anti-insulin resistance effects of 75% ethanol extracts of buckwheat (EEB) in FL83B hepatocytes by high-glucose (33 mM) induction and in C57BL/6 mice by fructose-rich diet (FRD; 60%) induction. The active compounds of EEB (100 μg/mL; 50 mg/kg bw), quercetin (6 μg/mL; 3 mg/kg bw), and rutin (23 μg/mL; 11.5 mg/kg bw) were also employed to treat FL83B hepatocytes and animal. Results indicated that EEB, rutin, and quercetin + rutin significantly improved 2-NBDG uptake via promoting Akt phosphorylation and preventing PPARγdegradation caused by high-glucose induction for 48 h in FL83B hepatocytes. We also found that EEB could elevate hepatic antioxidant enzymes activities to attenuate insulin resistance as well as its antioxidation caused by rutin and quercetin. Finally, EEB also inhibited increases in blood glucose and insulin levels of C57BL/6 mice induced by FRD.