The Effect of Exogenous Melatonin on Kiwifruit Phenolic Compounds and Antioxidant Capacity under low light environment

Abstract

Melatonin (N-acetyl-5-methoxytryptamine) is a low-molecular-weight molecule having an indole ring structure and considered as the best antioxidant substances. However, the role of melatonin in low light stress remains unknown. Our study investigated the possible role of melatonin on secondary metabolite and antioxidant capacity, involving total phenolics (TPC), flavonoids (TFC), flavanols (TFAC), FRAP, DPPH, and ABTS. The change trend of phenolic compounds and antioxidant capacity for different concentrations melatonin groups is basically the same. The results indicated melatonin significantly increased the phenolic compounds content and enhanced the antioxidant capacity compared to control group. In general, the 200 μM group had the markedly effect, 100 μM group followed, 50 μM group in the end.