Comprehensive Chemical Profiling and Assessment of In-Vitro Antioxidant and Antidiabetic Activities of Polysaccharides Derived from Allium cepa and Allium sativum.

Abstract

Objectives: Polysaccharides from diverse plant species have been consumed since ancient times to meet human energy needs. In recent years, plant-derived polysaccharides have gained scientific interest for their potential medicinal properties. Multiple studies indicate that these compounds exhibit a wide range of pharmacological activities. This study evaluated the antioxidant and antidiabetic properties of polysaccharides extracted from Allium sativum (ASP) and Allium cepa (ACP).

Methods: Polysaccharides were isolated by hot-water extraction followed by ethanol precipitation. The extracts were chemically characterized through phytochemical tests and FT-IR analysis. Antioxidant and antidiabetic activities were assessed using DPPH radical scavenging, α-glucosidase and α-amylase inhibition assays, and an in vitro glucose uptake assay.

Results: Polysaccharides from both species were pale yellow in color. Total carbohydrate content was 76.12% for ASP and 72.93% for ACP. FT-IR analysis indicated the presence of reducing sugars and pectic polysaccharides. ASP showed stronger DPPH radical scavenging activity (IC₅₀ = 85.7 ± 1.06 μg/mL) than ACP (IC₅₀ = 99.38 ± 1.39 μg/mL), though both were less potent than ascorbic acid. ASP also demonstrated greater α-amylase inhibition (IC₅₀ = 61.57 ± 0.86 μg/mL) compared with ACP (IC₅₀ = 72.82 ± 2.51 μg/mL). α-Glucosidase inhibition was similar between ASP (IC₅₀ = 69.56 ± 1.31 μg/mL) and ACP (IC₅₀ = 68.61 ± 2.09 μg/mL). Both extracts enhanced glucose utilization in a dose-dependent manner, with ASP showing the highest glucose stimulation at 758.3 μg/mL, significantly increasing glucose uptake relative to untreated controls.

Conclusion: Polysaccharides from Allium species exhibit promising potential to be used in diabetes therapy. Further in vivo studies and clinical trials are required to confirm these findings.