Wheat bread supplemented with onion peel extract and onion powder ameliorates dyslipidaemia and inflammation in alloxan-induced diabetic rats

Abstract Recurrent hyperglycaemia and dyslipidaemia are primary challenges in diabetes management. This study investigated the hypolipidaemic and anti-inflammatory effects of wheat bread supplemented with 2% and 4% ethanolic onion ( Allium cepa L.) peel extract (OP) and 4% and 6% onion bulb powder (OB) in alloxan-induced diabetic rats. After 42 days of supplemented bread consumption, diabetic rats demonstrated significant reductions in blood glucose, insulin, and liver enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyl transferase (GGT). Additionally, the levels of triglycerides, total cholesterol, very-low-density lipoprotein cholesterol (VLDL-C), and low-density lipoprotein cholesterol (LDL-C) significantly decreased, while high-density lipoprotein cholesterol (HDL-C) levels improved. Notably, breads containing 4% OP and 6% OB significantly reduced the levels of the inflammatory markers interleukin-1 beta (IL-1β) and monocyte chemoattractant protein-1 (MCP-1), indicating anti-inflammatory effect, though reductions in other inflammatory markers were not significant ( P < 0.01). The results suggest that both OP and OB, particularly at 4% and 6% concentrations, respectively, demonstrate strong potential for incorporation into functional foods aimed at managing hyperglycaemia, dyslipidaemia, and inflammation in patients with diabetes.