Radical scavenging and antioxidant features of nano-pomegranate (Punica granatum L.) peel powder extracts Kishk Yasser F.M.1*, Fattah Abdel Fattah A. Abdel1, El-Beltagy Allaa E.1, El-Sayed Mahmoud E.1, Khalil Sabry1, Alharthi Salman S.2 1Department of Food Science and Nutrition, College of Science, Taif University, P.O. Box 11099, Taif21944, Saudi Arabia 2Department of Chemistry, College of Science, Taif University, P.O. Box 11099, Taif21944, Saudi Arabia *Corresponding author e-mail: yfkishk@tu.edu.sa
Online Published on 06 January, 2022. Abstract The replacement of synthetic antioxidants with natural antioxidants from agricultural waste has become a global interest due to their adverse effects on human health. Nanotechnology can facilitate the extraction of natural compounds. In this study, the preparation and characterization of nano-pomegranate peel powder fractions and their extracts were described. The nano-fractions (NPP45 and NPP90) were prepared by ultrafine grinding of the crude pomegranate peel powder (CPP) for 45 and 90 min. Extracts using different solvents were subjected to determine total phenolics (μg gallic acid equivalent (GAE)/ml extract), 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (RSA), reducing power (RP), ferric reducing antioxidant power (FRAP). Polynomial quadratic regression was employed to calculate the predicted optimal RSA and FRAP and protective factor (PF) values. The mean particle size of NPP45 and NPP90 were 373 and 125nm, respectively. NPP90 methanolic extract had the highest phenolics content of 1.54 ± 0.04 μg GAE/ml compared to the methanolic CPP extract that contained 1.18 ± 0.03 μg GAE/ml with a 30.5% increase. The RSA, PF, RP and FRAP values were 94.1 ± 0.2%, 2.6, 0.76 ± 0.03 and 0.76 ± 0.03, respectively for the NPP90 methanolic extract. NPP90 methanolic extract reflected antiradical and antioxidant efficiency which was comparable with the efficiency of BHT (153.1 ppm). The results from the study showed potential replacement for BHT as a synthetic antioxidant with the natural NPP90 phenolics. This is the first time that an attempt has been done towards the extraction of phenolic compounds from pomegranate peels using nanotechnology. Top Keywords Pomegranate, Phenolics, Nanoparticles, Free radical, Natural antioxidants. Top |