Volume 1, Issue 2, 2019, Pages 104 - 112

Author(s) : Shohreh Mallakian* ¹

Abstract :
In recent years, extensive research has been conducted on the properties of various plant extracts and methods of extracting these extracts simultaneously. In this research, in addition to achieving the antioxidant properties of plant extracts, optimal methods for extraction have been used to replace the previous methods. According to the results of a study, one of the rich sources of bioactive compounds that have been extracted in various ways so far, is olive leaf extract, which due to its phenolic compounds, has significant antioxidant and antimicrobial effects. In this study, the antioxidant properties of phenolic compounds extracted from olive leaves were investigated using the method of extraction of subcritical water. The extraction process was carried out at temperatures of 120 to 180°C, under pressure corresponding to the extraction temperature and the mixing ratio of 1:20, and physicochemical properties (efficiency, turbidity and brix), antioxidant properties (total phenolic compounds by Folin-Ciocalteu method and amount). Free radical inhibition by DPPH method was investigated in the extract. The results showed that the highest amount of phenolic compounds was obtained from the extract of the extracurricular liquid extraction method at a temperature of 180°C, 8.08 mg per 100 g of dry matter in terms of gallic acid. The free radical inhibition power increased from 120 to 180°C, and the results showed that radical receptor activity was also higher in the extracted extract at 180°C. Overall, the results of the mean comparison showed that the efficacy, brix, phenolic compounds, and free radical inhibitory power of extractive extracts by the subcritical water method were higher than the extracts obtained by the extract maceration (P >0.05).

Keywords :
Antioxidants, Olive leaves, Subcritical water, Phenolic compounds