Effects of selected functional ingredients derived from agricultural sources on glycemic regulation in diabetes

The global burden of non-communicable diseases (NCDs) is progressively escalating, with the prevalence of diabetes projected to increase from approximately 180 million cases in 2010 to 368 million by 2030. Diabetes remains a major contributor to global morbidity and mortality, exerting substantial adverse effects on health outcomes and markedly diminishing quality of life. Epidemiological studies consistently demonstrate that dietary patterns characterized by high intake of refined carbohydrates and low dietary fibre (DF) consumption are associated with an increased risk of metabolic disorders, including cardiovascular disease and type 2 diabetes mellitus. Overripe bananas, which are commonly discarded as agricultural waste, represent a valuable source of bioactive constituents, particularly dietary fibres and natural sugars, and exhibit considerable antioxidant potential. This study investigates the utilization of natural sweeteners and dietary fibres derived from overripe banana extract (OBE) for the development of nutritionally enhanced food products. Extraction parameters, including solid-to-solvent ratio, temperature, and incubation time, were systematically optimized using a central composite design. The evaluated responses comprised total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity, and ferric reducing antioxidant power (FRAP). The findings demonstrate that extraction temperature and time exert a significant influence on the recovery of bioactive compounds, with moderate extraction conditions achieving maximal yields while limiting the thermal degradation of heat-sensitive constituents. Optimal extraction conditions were determined as a banana: water ratio of 1:3.2 (w/w), temperature of 51.5oC, and incubation time of 33.5 min. Predicted values under these conditions were 84.7 mg GAE/100 g for TPC, 69.5 mg CEQ/100 g for TFC, 75.1 % for DPPH, and 25.8 mM TE/g for FRAP. Experimental validation closely matched these predictions, yielding 85.3 mg GAE/100 g for TPC, 68.9 mg CEQ/100 g for TFC, 76.5 % for DPPH, and 26.8 mM TE/g for FRAP. In glycaemic index determination, the blood glucose response of 15%OBE cookie showed a significantly lower as compared to other test foods. The cookies formulated with 15% OBE to replace table sugar recorded GI values of 50 (low). This work demonstrated that overripe bananas can be an alternative novel DF-rich and low-GI food ingredient, which could widely be utilized in developing various overripe banana based functional foods. By leveraging overripe bananas, this work supports sustainability and promotes the development of high-value functional ingredients.
Keywords: Overripe Banana, Diabetes, Glycaemic Responses, Nutritional Composition

Wan Rosli Wan Ishak is a professor of Nutrition Program at the School of Health Sciences (SHS), Universiti Sains Malaysia (USM), Health Campus, Kota Bharu, Kelantan, Malaysia. Currently, he is a Dean of SHS of USM since 2022. His research theme emphasizes more on the utilization of natural agricultural by-products into popularly consumed processed foods. Various low glycemic index (GI) based on these agricultural by-products have been developed. He was selected among Top 10 Innovators for SYMBIOSIS project funded by Malaysian Technology Development of Malaysia (MTDC) to facilitate the commercialization of functional and health cookies from oyster mushroom (Nutri-Mush® Cookies). He has also transferred one technology licensing to PS Foods and Beverage Sdn Bhd, a Malaysian company on the commercialization of overripe banana extract. Besides, he has published more than 160 articles in various renowned indexed journals.