Valorization of Watermelon Peel Flavonoids: Kaempferol, Quercetin, and Rutin as Natural Antioxidants for Functional Food and Nutraceutical Applications
Year: 2026
Type: article
Abstract: Watermelon peel, an abundant by-product generated during fruit processing and consumption, represents an underutilized source of naturally occurring bioactive compounds. Among its phytochemical constituents, flavonoids such as rutin, quercetin, and kaempferol exhibit well-documented antioxidant properties that make them attractive candidates for functional food and nutraceutical applications. The present study employed a predictive research approach to evaluate the expected influence of different extraction strategies on the recovery of these flavonoids and their associated antioxidant potential. No laboratory experimentation or chemical analyses were performed. Instead, predictions were developed by integrating established scientific knowledge regarding flavonoid occurrence in watermelon peel, antioxidant mechanisms, solvent extraction principles, and physicochemical characteristics reported in the scientific literature. Four extraction treatments were comparatively evaluated: untreated watermelon peel powder (Control), aqueous extraction (T1), 50% ethanol extraction (T2), and 70% ethanol coupled with ultrasound-assisted extraction (T3). The predictive assessment suggests progressive enhancement of flavonoid recovery, total phenolic content, antioxidant capacity, and functional antioxidant performance with increasing extraction efficiency. Among the three flavonoids, rutin is predicted to remain the predominant compound recovered from watermelon peel, whereas quercetin is expected to contribute the greatest antioxidant activity because of its superior radical-scavenging capability. The findings indicate that watermelon peel possesses substantial potential as a sustainable natural antioxidant source for functional food ingredients and nutraceutical formulations. These predicted outcomes provide a scientific basis for future experimental validation and industrial utilization of watermelon processing waste.
Source: Journal for Current Sign
Author: Journal for Current Sign
Language: English
Subfield: Biochemistry (medical)
Field: Medicine
Domain: Health Sciences
SDG: Zero hunger
Open Access status: bronze
OpenAlex ID: W7167603825