Evaluation of Antidiabetic and Antiobesity Effects of Underutilized Starch Sources Compared to Refined Wheat Flour.

Abstract

Unconventional and underutilized flours are rich sources of phytochemicals compared to refined wheat flour. Phytochemicals are key secondary metabolites inhibiting digestive enzymes like α-amylase and pancreatic lipase, crucial in glucose and triglyceride absorption. Replacing refined wheat flour with these unconventional flours may offer a natural alternative for managing hyperglycemia and hyperlipidemia without the side effects associated with synthetic drugs. This study explores the antidiabetic and antiobesity activities of flours from Jaggery palm (Caryota urens), Palmyra tuber (Borassus flabellifer), Defatted Coconut (Cocos nucifera), Waterlily seed (Nymphaea lotus), Cycad seed (Cycas circinalis), and Jackfruit seed (Artocarpus heterophyllus), comparing them with refined wheat flour. The inhibitory properties of refined wheat and underutilized flour extract against α-amylase and pancreatic lipase were evaluated using soluble starch and p-nitrophenyl butyrate (p-NPB) as substrates, respectively. Synthetic inhibitors Acarbose and Orlistat were used as positive controls for the α-amylase and lipase inhibitory assays. All analyses were performed in triplicate and compared using Tukey‟s test. All unconventional flours exhibited significantly higher (P ≤ 0.05) α- amylase inhibitory activity compared to refined wheat flour, with waterlily seed flour showing the highest activity (2.88 ± 0.27) followed by flours from Cycas circinalis (12.07 ± 0.16), Jackfruit seed (15.57 ± 0.14), Jaggery palm (25.26 ± 0.22), Coconut (27.47 ± 2.17), and Palmyra (33.29 ± 1.52). Lipase inhibitory activity of the flours ranged from 46 mg/ml to 21 mg/ml, with Palmyra (23.50 ± 7.62), Defatted Coconut (21.04 ± 5.42), Waterlily (28.49 ± 4.09), and Jackfruit seed (26.88 ± 1.42) showing significantly (P ≤ 0.05) higher activity than refined wheat flour. Jaggary Palm (44.7 9± 0.91) and Cycas circinalis flours (46.96 ± 1.08) had lower (P ≤ 0.05) inhibitory activity than refined wheat flour. Overall, all flour extracts except waterlily seed flour exhibited weaker α-amylase and lipase inhibition than the synthetic drugs. While waterlily seed flour showed α-amylase activity comparable to Acarbose, its lipase inhibition was inferior to Orlistat.