RESUMO
Peruvian corn biodiversity is one of the highest in the world and may represent an important natural source of health relevant phenolic bioactive compounds whose potential needs to be investigated. This study investigated twenty-two Peruvian corn samples corresponding to five corn races (Arequipeño, Cabanita, Kculli, Granada and Coruca) in relation to their total phenolic contents (TPC), anthocyanin contents, Ultra-Performance Liquid Chromatography (UPLC) phenolic profiles and antioxidant capacity (ABTS and ORAC methods). Subsequently using both free and cell-wall bound phenolic fractions their health relevance targeting hyperglycemia (α-glucosidase and α-amylase inhibition) and obesity (lipase inhibition) potentials was evaluated using in vitro assay models. Antioxidant capacity and TPC were high in bound fractions from yellow-colored races in contrast to the purple-colored race (Kculli) which had high TPC (mainly anthocyanins) and antioxidant capacity in the free form. The major phenolic acids detected by UPLC were ferulic and p-coumaric acids. High α-glucosidase (32.5-76.1%, 25 mg sample dose) and moderate α-amylase inhibitory activities (13.6-29.0%, 250 mg sample dose) were found in all free fractions, but only samples from the Kculli race had lipase inhibitory activity (58.45-92.16%, 12.5 mg sample dose). Principal component analysis revealed that the variability of data was affected by the race and the α-glucosidase and lipase inhibitory activities positively correlated with anthocyanins and antioxidant capacity. Some accessions of Kculli, Granada and Cabanita races are promising for future breeding strategies focused on the development of improved corn varieties targeted for the design of functional foods relevant for hyperglycemia and obesity prevention.
RESUMO
The purpose of the present investigation is to assess, for the first time, the antidiabetic, antihyperlipidemic and antioxidant activities of Lycium europaeum extract in alloxan-induced diabetic rats. Diabetes was induced in adult male Wistar rats via a single subcutaneous alloxan injection (120 mg/kg). Lycium europaeum aqueous extract was orally administered at a dose of 20 mg/kg for 28 consecutive days. Serum concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) were assayed at the end of the experimental period in all investigated groups. Antioxidant enzymes such as glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) were sought in the serum and pancreas. Lycium europaeum extract significantly increased HDL-C and reduced blood glucose, TC, LDL-C and TG as compared to the alloxan-control group. Lycium europaeum extract was also efficient in reducing oxidative stress in diabetic rats by increasing SOD, CAT and GPx activities both in the pancreas and the plasma of the animals. Moreover, Lycium europaeum extract contained considerable levels of polyphenols and flavonoids. It also exhibited an important antioxidant capacity and a remarkable ability to quench DPPH radicals and reduce irons. The obtained results highlight potentially relevant health beneficial effects of Lycium europaeum extract, reversing hyperglycemic, hyperlipidemic and oxidative stress effects in rats with alloxan-induced diabetes. Therefore, it may be considered as a promising alternative or complementary agent to diabetes treatment.
RESUMO
The hypoglycemic effects of hexane, chloroform and methanol extracts from fruits of Ferocactus latispinus and Ferocactus histrix were evaluated by oral administration to normoglucemic and streptozotocin-induced severe diabetic rats (SD). The anti-diabetic effect was examined by blood glucose, triglycerides, lipid peroxidation, total cholesterol levels in the serum, glycogen content of liver and skeletal muscles, superoxide dismutase (SOD) catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GSHPx) levels. The most active extracts were obtained with chloroform. Chloroform extracts from F. latispinus and F. histrix increased activities of SOD, GR, GSHPx and CAT, hepatic glycogen content, glucose-6-phosphatase (G6Pase) and the plasma insulin levels. They also, decreased glucokinase (GK) and TBAR (thiobarbituric acid assay). Of the two plants studied F. latispinus showed better antihyperglycemic and antihyperlipidemic effects that F. histrix. In conclusion F. latispinus and F. histrix possesses significant antihyperglycemic properties after 4 h after a single oral dose. It can also improve hyperlipidemia and hypoinsulinemia in streptozotocin-induced diabetic. These results demonstrated that F. latispinus and F. histrix typically used as a health food, has strong antidiabetic effects in vivo, thus, it may have beneficial properties in the prevention of diabetes.
Los efectos hipoglucemiantes de extractos obtenidos con hexano, cloroformo y metanol a partir de frutos de Ferocactus latispinus y Ferocactus histrix fueron evaluados por la administración oral a ratas normales y con diabetes severa (SD) inducida por estreptozotocina. Los extractos más activos fueron obtenidos con cloroformo el cuál incrementa los niveles de SOD, GR, GSHPx y el CAT, el contenido de glucógeno hepático, la glucosa-6-fosfatasa (G6Pase) y los niveles de insulina plasmática. También producen disminución de la glucoquinasa (GK) y TBARS. De las dos plantas estudiadas la F. latispinus presento mayor actividad antihiperglicemiante y antihiperlipidémicos que la F. histrix. En conclusión F. latispinus y F. histrix pueden mejorar la hiperlipidemia y la hipoinsulinemia en animales diabéticos inducida por estreptozotocina. Estos resultados demostraron que F. latispinus y F. histrix utilizadas normalmente como un alimento saludable, tiene fuertes efectos antidiabéticos in vivo, por lo tanto, pueden tener propiedades beneficiosas en la prevención de la diabetes.