Antiradical and antihyperglycemic activity of raspberry pomace

Plant foods and products are rich sources of a variety of biologically active compounds possessing wide range of biological activities such as hypolipidemic, antiplatelet, antitumor, antioxidant, and immunostimulating properties. Enzyme inhibitors have potential value, in many areas of disease control and treatment. α-Glucosidase is a therapeutic target for type ii diabetes, and α-glucosidase inhibitors have been used in the clinic as alternative treatments for this disease. There is a growing interest to reduce waste and to study the possibility of using by-products, such as pomace from fruit processing industry, for isolation of bioactive compounds. for this purpose, raspberry pomace, Meeker variety, was extracted and screened for the presence of biologically active compounds with antiradical and α-glucosidase enzyme-inhibitory activity. in order to characterize the raspberry pomace as a source of bioactive compounds, total polyphenol (6.15 mg/g pomace), flavonoid (3.87 mg/g pomace) and anthocyanin (0.66 mg/g pomace) contents in the extract were determined spectrophotometrically, while the presence of vitamin C (1.41 mg/g pomace) was determined by hPlC. Raspberry pomace extract exhibited antihyperglycemic activity, inhibiting α-glucosidase activity at the concentration range from 0.04 to 0.63 mg/ml. inhibitory activity reached 50 % applying 0.2 mg/ml of raspberry pomace extract. Antiradical activity of raspberry pomace extract, evaluated by AbTS assay, was 1.17 mM Trolox equivalents at the concentration of 3.33 mg/ml. Results obtained in this study show that rasberry pomace is a natural source of effective and safe bioactive compounds for development of functional foods to treat diabetes and oxidative stress related diseases.