Evaluation of the antioxidant activity of Betula pendula leaves extract and its effects on model foods

Nurul Aini Mohd Azman,Monika Skowyra,Kwestan Muhammad,María Gabriela Gallego,Maria Pilar Almajano

doi:10.1080/13880209.2017.1282528

Abstract

Context: Betula pendula Roth (Betulaceae) exhibits many pharmacological activities in humans including anticancer, antibacterial, and antiviral effects. However, the antioxidant activity of BP towards lipid degradation has not been fully determined.Objective: The BP ethanol and methanol extracts were evaluated to determine antioxidant activity by an in vitro method and lyophilized extract of BP was added to beef patties to study oxidative stability.Materials and methods: Antioxidant activities of extracts of BP were determined by measuring scavenging radical activity against methoxy radical generated by Fenton reaction 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (TEAC) radical cation, the oxygen radical absorbance capacity (ORAC) and the ferric reducing antioxidant power (FRAP) assays. The lipid deterioration in beef patties containing 0.1% and 0.3% (w/w) of lyophilized extract of BP stored in 80:20 (v/v) O2:CO2 modified atmosphere (MAP) at 4 °C for 10 days was determined using thiobarbituric acid reacting substances (TBARS), % metmyoglobin and colour value.Results: The BP methanol extract revealed the presence of catechin, myricetin, quercetin, naringenin, and p-coumaric acid. The BP ethanol (50% w/w) extract showed scavenging activity in TEAC, ORAC and FRAP assays with values of 1.45, 2.81, 1.52 mmol Trolox equivalents (TE)/g DW, respectively. Reductions in lipid oxidation were found in samples treated with lyophilized BP extract (0.1% and 0.3% w/w) as manifested by the changes of colour and metmyoglobin concentration. A preliminary study film with BP showed retard degradation of lipid in muscle food.Conclusion: The present results indicated that the BP extracts can be used as natural food antioxidants.

Highlights

Nowadays, consumers are increasingly interested in natural foods, a healthy diet, and concern about possible toxicological effects of the synthetic antioxidants used in the food industry
The Betula pendula (BP) extract prepared with 50% aqueous ethanol showed a high phenolic content and antioxidant activity measured by the ferric reducing antioxidant power (FRAP), TEAC and oxygen radical absorbance capacity (ORAC) assays
The various polyphenol constituents present in the BP extract contribute to the antioxidant activity and total polyphenol content

Summary

Introduction

Consumers are increasingly interested in natural foods, a healthy diet, and concern about possible toxicological effects of the synthetic antioxidants used in the food industry. Natural antioxidants owe their activity mainly from polyphenol compounds found in most herbal plants, fruits, and vegetables. Recent strategy has focused on the development of active packaging systems based on the incorporation of natural antioxidants into food packaging formulations (Gomez-Estaca et al 2007; Bao et al 2009) This eco-friendly biodegradable packaging provides safety benefits to the food, successfully controls food quality and extends the shelf life, and replaces commercial non degradable plastic which is harmful to the environment. Gelatin, which is obtained by collagen hydrolysis, is one of the popular ingredients in film making and its advantages include film forming ability (Ali et al 2014)

Objectives

Methods

Results

Conclusion