Comparison of total phenol content and antioxidant activity of herbal infusions with added Stevia reabaudiana Bertoni

Elvia Guadalupe DIAZ-OCHOA,Ma Claudia CASTAÑEDA-SAUCEDO,Ernesto TAPIA-CAMPOS,Jessica del Pilar RAMÍREZ-ANAYA

doi:10.1590/fst.29718

Abstract

Abstract Antioxidant capacity (AC) was determined by the ABTS method and DPPH, and total phenol content (TPC) in dehydrated plant material, in infusions and in residues (plant material after preparing the infusion) of white, black, red, green, spearmint, stevia, lemon grass and chamomile teas to which stevia leaves were added or not added; addition of processed stevia powder was also tested. Three independent experiments were set up: with dehydrated plant material, with infusions and with residues. For the case of dehydrated plant material, white tea had the highest TPC (10813.5 mg GAE/100g) and AC by the ABTS method (1183.3 µM TE/g) and DPPH method (1525.0 µM TE/g). In infusions, black tea had higher TPC (180.82 µg GAE/ml) and AC by the methods ABTS and DPPH (0.6114 and 2.5983 µM TE/ml, respectively). In residues, TPC was higher in white tea, while green tea had the highest AC values. AC of dehydrated plant material increased when stevia leaves were added, according to the DPPH and ABTS methods, but not in residues by ABTS. Addition of stevia leaves in infusions increased AC in white, lemon grass, chamomile and stevia teas by the ABTS method and in spearmint, black, red, and green teas with the DPPH method.

Highlights

An infusion is a beverage obtained from parts of the shoot of several herbs or aromatic plants
Most of the infusions are prepared from two types of manufactured teas: black and green teas (Konieczynski et al, 2017), which are obtained from Camellia sinensis leaves, as are white and red teas
A two-factorial analysis was used in which one factor was the plant material; the other factor was the addition of 0.25 g dehydrated ground stevia leaves (ASL), commercial processed powdered stevia (PS) (Member’s Mark) and without stevia (WSL)

Summary

Introduction

An infusion is a beverage obtained from parts (dry leaves, flowers and fruits) of the shoot of several herbs or aromatic plants. Consumption of infusions has increased because of their beneficial properties, which are attributed to the presence of phenolic compounds (Cleverdon et al, 2018) These compounds have higher antioxidant capacity than fruits and vegetables and are even more potent than vitamin C, E and carotenoids (Wiseman et al, 1997). Because of these characteristics, teas are often used as remedies to cure diverse organic disorders. The aim of this study was to compare TPC and AC in dehydrated plant material, infusions and residues of white, black, red, green, spearmint, stevia, lemon grass and chamomile teas with or not addition stevia leaves and processed stevia

Objectives

Methods

Results

Conclusion