Antidiabetic and antioxidant potentials of spent turmeric oleoresin, a by-product from curcumin production industry

ObjectiveTo investigate the antidiabetic and antioxidant activity of spent turmeric oleoresin (STO).MethodsAntidiabetic activity of STO evaluated by α-amylase and α-glucosidase enzyme inhibition assays. The antioxidant capacity studied by DPPH., ABTS., superoxide radical scavenging and metal chelating activity methods.ResultsThe STO showed good antidiabetic activity by inhibiting key enzymes linked to type 2 diabetes, viz α-glucosidase and α-amylase with an IC50values of 0.71 and 0.16μg/mL respectively. The IC50values for DPPH. and ABTS. assay were 58.1 and 33 μg/mL respectively. STO effectively scavenged the superoxide free radical with an IC50 value of 61.5μg/mL and showed a moderate iron chelation property.ConclusionsThe above study reveals that the spent turmeric oleoresin being wasted at present can be used as antioxidant and antidiabetic agent in food and neutraceutical products.