Formulation and Assessment of Antidiabetic Polyherbal Preparations Containing Azadirachta indica, Tinospora cordifolia, and Ocimum sanctum in Streptozotocin- Nicotinamide-Triggered Diabetic Rats: Comparative Evaluation with Glibenclamide

Abstract

Background: A chronic metabolic abnormality marked by elevated plasma glucose concentration that results
from defects in insulin production or function is termed diabetes mellitus. This study was conducted to formulate
and investigate polyherbal combinations with Azadirachta indica, Tinospora cordifolia, and Ocimum sanctum
for their antioxidant and antidiabetic potential. Methods: Standardization of plant materials was carried out by
pharmacognostic and physicochemical evaluations, followed by preparation of ethanol and aqueous extracts. The
analysis of phytochemical constituents confirmed the occurrence of glycosides, flavonoids, polyphenols, and
alkaloids. The antioxidant potential of sample to scavenge free radicals was analyzed employing the 2,2-diphenyl-
1-picrylhydrazyl (DPPH) method, hydrogen peroxide scavenging, total phenolic, and flavonoid content assays.
Eight polyherbal formulations (F1–F8) were prepared and evaluated to investigate the antidiabetic potential in vivo
activity in Wistar rats through oral glucose tolerance test and diabetes triggered by streptozotocin-nicotinamide
in experimental animals. Results: Among individual extracts, the hydroalcoholic-free phytochemical extract of
Ocimum sanctum exhibited the highest antioxidant activity inhibitory concentration 50 (IC50) of 28.29 μg/mL,
DPPH assay. The extract contained phenolics at 69.5 mg (gallic acid equivalents per gram [GAE/g]) and flavonoids
at 65.7 mg (GAE/g). In-vivo, polyherbal formulations significantly reduced blood glucose compared with diabetic
controls, with F7 and F8 showing the greatest improvement. Formulations also improved lipid profile, enhanced
insulin levels, and preserved pancreatic β-cell structure. Conclusion: The synergistic effects of A. indica,
T. cordifolia, and O. sanctum in polyherbal formulations demonstrated potent antioxidant and antidiabetic
activities, supporting their traditional use and therapeutic potential for diabetes management