Influence of ripening stages and drying methods on polyphenolic content and antioxidant activities of mulberry fruits

This study highlights the influence of ripening (un-ripen, semi-ripen and fully-ripen) and drying (fresh, ambient-dried and sun-dried) on the extract yield, total phenolic contents (TPC) and total flavonoid contents (TFC) of different species (Morus alba, M. nigra, M. macroura and M. laevigata) of mulberry fruit. 1,1-Diphenyl-2-picryl hydrazyl scavenging assay and reducing ability was used to assess the antioxidant capacity of the extracts. An increasing trend in the extract yield (2.9-56%), TPC (201-2287 mg/100 g GAE), TFC (58-1021 mg/100 g CE) and antioxidant activity was observed as the maturity of fruits progressed. On the other hand, fully ripened mulberry fruit at air drying conditions generally have higher antioxidant activity. The ripening stages, as well as the drying conditions has a significant impact on the polyphenols and antioxidant attributes of mulberries.