Studies on Polyphenol Content, Flavonoid Content and Antioxidant Activity of Graviola Tea pulp (Annona muricata L.) from Tien Giang Province, Vietnam

Abstract

Tea is the most commonly consumed beverage worldwide due to promote health and prevention of some human diseases. Soursop tea pulp is one of a new product focused on the values of total ascorbic acid (TAA), total polyphenol content (TPC) and total flavonoid content (TFC). A study using DPPH and ABTS method to detect the maximum of active ingredients in tea simultaneously. Different pulp tea samples with varying dates of production checked for TAA, TPC, TFC, antioxidation and sensory evaluation. There is a difference in TAA between sample (1) and (4), achieved 7.43 ± 0.04 mg/g DM and 12.21 ± 0.04 mg/g DM, respectively. TFC content ranged between 0.13 and 0.18. The phenolics group in tea is high and there are differences between the 3 recent production samples with (1): 3.81 mg QC/g DM fluctuation. In sample 1, the antioxidant activity of the ethanol extract of Soursop was correlated with total phenolic and flavonoid content with values IC50 of 0.26 mgAA/g DM, 2.61 mgAA/g DM for DPPH and ABTS scavenging activity, respectively. Moreover, the Lab* colour space of the soursop tea is measured in the dark area, the L* difference achieved at 30.82 ± 1.24 (2) lowest and the highest 37.42 ± 4.77 (1). Consumer sensory evaluation is performed with results based on a 5-point scale describing: flavour, aroma, colour and favourite.