Akademik Veri Yönetim Sistemi
Akademik Gida, cilt.21, sa.3, ss.233-242, 2023 (Scopus)
Recently, there has been an increasing interest in phenolic component extraction from various by-products of food production due to the health benefits of phenolics like antioxidant activity. In the present study, microwave-assisted extraction (MAE), which is characterized as an efficient alternative and green technique for extraction, was used for the extraction of phenolic compounds from olive leaves. In addition, the effect of different microwave powers on the release kinetics of total phenolic contents in extracts was determined. Extraction efficiency and antioxidant properties of extracts were evaluated with increasing time in three different microwave powers of 100, 300 and 500W. It was observed that the antioxidant activities of extracts increased up to the 15th minute for the microwave power of 100W. Phenolic compound content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity values increased up to 10 minutes for the microwave power of 300W. It was found that both phenolic contents and antioxidant properties of extracts increased up to 4 minutes and then decreased with time for extracts with the microwave power of 500W. Among all extracts, the highest total phenolic content, DPPH radical scavenging activity, and metal chelating activity value were found for the extracts treated with 500W for 4 minutes as 9.52±0.21 mg gallic acid equivalent (GAE)/mL, 15.22±0.45 mg Trolox equivalent (TE)/g, and 98.13±0.04 µmol ethylenediaminetetraacetic acid (EDTA)/g olive leaves, respectively. According to the results of extraction kinetics, the Peleg model was found to be more suitable for MAE. Results indicated that the increased potency for MAE from olive leaves resulted in shorter extraction time. In addition, it was observed that longer time at high microwave powers might reduce the extraction efficiency of MAE.