Effect of Ursolic Acid-Enriched Chitosan Coating On the Shelf-Life Extension of Papaya

Abstract

Objectives: This study developed a chitosan-based antifungal coating enriched with ursolic acid (UA) extracted from basil and rosemary to extend papaya shelf life. It focused on UA extraction, purification, antifungal evaluation, and effectiveness in preserving papaya quality during storage. Methodology: UA was purified using column chromatography, confirmed through TLC and FTIR, and quantified by the vanillin-sulfuric acid colorimetric method. Its antifungal activity was tested against Candida albicans and Saccharomyces cerevisiae using the agar well diffusion method. 0.5g of Chitosan incorporated with varying UA concentrations (0.5, 1, and 1.5 g) were applied to papayas by dip and spray coating. The samples were evaluated for weight loss, titratable acidity, pH, soluble solids (°Brix), and color parameters over 9 days of storage at ambient temperature. Result and Discussion: UA extracted from rosemary (0.0142 mg/ml) and basil (0.0134 mg/ml) showed strong antifungal activity, particularly against C. albicans. Papayas coated with 1 g UA exhibited the least weight loss (0–2%), maintained higher pH (5.1–5.4), lower acidity (0.10%), and slower sugar increase, indicating delayed ripening. Color stability was significantly improved, with coated fruits showing minimal changes in L*, a*, and b* values. The control papaya spoiled on the 5th day, while the spray-coated samples began to spoil on the 7th day. In contrast, the chitosan-UA dip coated papaya remained fresh up to the 9th day. The results demonstrate that UA-enriched chitosan coatings provide an effective, natural, and eco-friendly method to preserve fruit quality and reduce postharvest losses.