The advancement in nanotechnology is the trigger for exploring the synthesis of selenium nanoparticles and their use in biomedicine. Therefore, this study aims to synthesize selenium nanoparticles using M. oleifera as a reducing agent and evaluate their antioxidant and antidiabetic potential. Our result demonstrated a change in the color of the mixture from yellow to red, and UV-Vis spectrometry of the suspension solution confirmed the formation of MO-SeNPs with a single absorbance peak in the range of 240–560 nm wavelength. FTIR analysis revealed several bioactive compounds, such as phenols and amines, that could possibly be responsible for the reduction and stabilization of the MO-SeNPs. FESEM + EDX analysis revealed that the amorphous MO-SeNPs are of high purity, have a spherical shape, and have a size of 20–250 nm in diameter, as determined by HRTEM. MO-SeNPs also exhibit the highest DPPH scavenging activity of 84% at 1000 μg/mL with an IC50 of 454.1 μg/mL and noteworthy reducing ability by reducing power assay. Furthermore, MO-SeNPs showed promising antidiabetic properties with dose-dependent inhibition of α-amylase (26.7% to 44.53%) and α-glucosidase enzyme (4.73% to 19.26%). Hence, these results demonstrated that M. oleifera plant extract possesses the potential to reduce selenium ions to SeNPs under optimized conditions with notable antioxidant and antidiabetic activities.

Background The search for efficient treatments for type 2 diabetes mellitus (T2DM) has highlighted the potential of plant-based therapeutic compounds and eco-friendly processes for producing selenium nanoparticles. This study investigates the antidiabetic potential of Moringa oleifera-mediated biogenic selenium nanoparticles (MO-SeNPs) in diabetic rats. Methods Male Sprague-Dawley rats were induced with diabetes via a high-fat diet for 2 weeks followed by a single intraperitoneal injection of streptozotocin (STZ) at 45 mg/kg body weight (BW). The rats were divided into five groups: normal, diabetic control, metformin at 100 mg/kg/BW, and two groups treated with oral administration of MO-SeNPs at 0.25 and 0.5 mg/kg body weight for 28 days. Food and water intake as well as fasting blood glucose and body weight were measured weekly. After the treatment period, rats were sacrificed, and blood and liver samples were harvested for further analysis. Results MO-SeNPs treatment significantly reduced blood glucose levels (p < 0.05) and restored insulin resistance, with lower dose demonstrating better glycaemic control than larger dose. MO-SeNPs also increased hepatic antioxidant enzyme activity, including GSH-Px, CAT, and T-SOD, which neutralise oxidative stress. MO-SeNPs also improves cardiovascular health by raising HDL and lowering LDL. MO-SeNPs showed hepatoprotective benefits by lowering inflammatory markers such TNF-α, IL-6, IL-1β, iNOS, and AGEs, and reduced lipid peroxidation. Diabetes raises inflammatory indicators, causing liver damage and other problems. The reduction in these indicators shows MO-SeNPs reduce liver inflammation and protect the liver. The normalisation of liver enzyme levels (ALT, AST, ALP) showed improved liver function. Conclusions The findings suggest that the green synthesis of SeNPs using Moringa oleifera offers a viable alternative for diabetes treatment, highlighting its potential to enhance glycemic control and improve overall metabolic health.