POLYPHENOL CONTENT OF AMARANTHUS HYBRIDUS AND CORCHORUS OLITORIUS STORED FOR THREE DAYS UNDER REFRIGERATING CONDITION

Polyphenols, including phenolic acids and flavonoids, are important bioactive compounds known for their antioxidant, anti-inflammatory, antidiabetic, and cardioprotective properties. These compounds are sensitive to postharvest storage conditions, which can impact their nutritional and therapeutic potential. This study investigated the effects of refrigerated storage for three days on the polyphenol content of two commonly consumed leafy vegetables; Amaranthus hybridus and Corchorus olitorius. Freshly harvested leaves of Amaranthus hybridus and Corchorus olitorius were collected, authenticated, and stored at 4°C for three days. Extracts were prepared from both fresh and refrigerated samples, and the total phenolic content (TPC) and total flavonoid content (TFC) were quantitatively analyzed using spectrophotometric methods based on Folin-Ciocalteu reagent and Aluminum chloride complexation, respectively. Results revealed a significant increase in TPC for both vegetables after refrigerated storage. Specifically, Amaranthus hybridus showed an increase in TPC from 43.90 ± 1.83 mg GAE/100g to 63.40 ± 1.95 mg GAE/100g, while Corchorus olitorius increased from 54.78 ± 1.61 mg GAE/100g to 68.98 ± 1.77 mg GAE/100g. However, the TFC in Amaranthus hybridus decreased slightly from 16.64 ± 0.16 mg QUE/100g to 13.63 ± 0.47 mg QUE/100g, indicating potential flavonoid degradation during storage. In contrast, Corchorus olitorius exhibited a significant increase in TFC from 25.71 ± 1.75 mg QUE/100g to 34.63 ± 3.43 mg QUE/100g, suggesting better flavonoid stability under refrigeration. This study concluded that short-term refrigerated storage is an effective postharvest strategy to preserve the polyphenolic content and antioxidant potential of Amaranthus hybridus and Corchorus olitorius.