Antimicrobial Effect of Chitosan-Aloe vera Gel Extract Composited with Organic Oils

This study evaluated the antimicrobial effects of chitosan-Aloe vera extract gel composite with organic oils (watermelon seed oil and orange seed oil) against microorganisms: Staphylococcus aureus, Pseudomonas aeruginosa, Aspergillus niger, and Aspergillus flavus. The phytochemical and antioxidant properties of the extract and the physicochemical properties of the oils were assessed. The antimicrobial activity was determined by the Minimum Fungicidal Concentration (MFC), Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC). The phytochemical analysis of Aloe vera extract revealed concentrations of alkaloids (29.72±0.65 mg/100g), tannins (142.03±0.99 mg/100g), flavonoids (113.82±1.83 mg/100g), phenols (565.68±1.36 mg/100g), and saponins (106.59±1.09 mg/100g). Antioxidant screening showed 61.38% for DPPH and 64.85% for FRAP, while ascorbic acid showed 98.75% at 500 μg/ml. Physicochemical properties of the oils showed watermelon seed oil had a higher iodine value (171.07±1.514 mgl2/g) and acid value (6.59±0.01 mg/KOH/g), while orange seed oil had the highest peroxide value (1.82±0.01 mgl2/g). The composite gel showed viscosity of 86.10%, swelling capacity of 1.07%, and water absorbing capacity of 68.03%. A. flavus was more sensitive than A. niger, while P. aeruginosa was more sensitive than S. aureus. The study suggests that chitosan-Aloe vera extract gel with organic oils is an effective antimicrobial agent against pathogenic microorganisms.