Formulation and Evaluation of Garlic Oil–Zinc Oxide Nanoparticle Gel for In-Vitro Anti-Inflammatory and Antioxidant Activitiy

Abstract

Background: Garlic oil (GO) contains organosulfur compounds with reported antioxidant and anti-inflammatory properties, whereas zinc oxide nanoparticles (ZnO NPs) are of interest for topical delivery systems.

Aim: To prepare GO-mediated ZnO NPs, formulate them into a topical gel, and evaluate in vitro antioxidant and anti-inflammatory activities.

Methods: GO-ZnO NPs were synthesized from zinc acetate using garlic oil and incorporated into a gel base. Appearance, odour, pH, and centrifugation stability were assessed. Antioxidant activity was evaluated by DPPH and FRAP assays; albumin denaturation assessed anti-inflammatory activity. Ascorbic acid and diclofenac sodium served as standards.

Results: The gel was pale white, garlic scented, and had pH 5; phase separation occurred after centrifugation. GO-ZnO NPs produced 78% DPPH inhibition at 10 mg (IC50 14.50 mg), whereas gel produced 90% inhibition at 5 mg (IC50 9.76 mg); ascorbic acid IC50 was 3.373 mg. At 15 mg, FRAP absorbance was 1.53 for NPs and 1.43 for gel. Albumin-denaturation inhibition was 55% at 5 mg for NPs (IC50 15.83 mg) and 62% at 10 mg for gel (IC50 6.09 mg); diclofenac IC50 was 12.129 mg. Alkaloids were detected.

Conclusion: Both preparations demonstrated activity; however, instability and non-linear responses require formulation optimization and validation before topical application.