Ultrasound-assisted extraction of phenolic compounds from Phyllanthus emblica L. and evaluation of antioxidant activities

Synopsis ObjectiveThe objective of this study was to optimize ultrasound-assisted extraction of phenolic compounds from Phyllanthus emblica. MethodsExtracts obtained by UAE were evaluated for their antioxidant activities. Extraction experiments were carried out with three factors and three levels namely extraction time (varying from 15 to 60min), ethanol concentration (varying from 50 to 90%) and frequency (varying from 28 to 56kHz). ResultsThe results showed that the UAE optimal conditions of extracting total phenol components were as follows: 15min of extraction time, 60 degrees C of extraction temperature, 70% of ethanol concentration, 56kHz of ultrasonic frequency and a 1: 50 solid to solvent ratio. Under optimal conditions, the leaching-out rate of phenolic compounds was up to 55.34mgg(-1), and the yield of crude extract of P.emblica was up to 56.82%. The results reveal that the yield of phenolic compounds of UAE (56.82%) is higher than that of conventional solvent extraction (16.78%). Furthermore, the antioxidant activities of ethanol extracts obtained by UAE were evaluated in terms of activities of DPPH (1,1'-diphenyl-2-2'-picrylhydrazyl) radical scavenging activity, total antioxidant activity, metal chelating activity, and reducing power. P.emblica extracts obtained by UAE showed high antioxidant activity (26.00, 50.11 and 115.91gmL(-1) of IC50 values for DPPH radicals, total antioxidant ability and chelating ability of ferrous ion). ConclusionThe result of this study showed that UAE was a suitable method for the extraction of total phenolic compounds. Moreover, the author's main finding in this work is the fact that phenolic compounds from P.emblica show excellent antioxidant activity in multi-test systems. Resume ObjectifL'objectif de cette etude etait d' optimiser l'extraction assistee par ultrasons (EAU) des composes phenoliques de P. emblica. MethodesLes extraits obtenus par les EAU ont ete evalues quant a leurs activites anti-oxydantes. Des experiences d'extraction ont ete effectues avec trois facteurs et trois niveaux de temps a savoir l'extraction (variant entre 15 et 60 min), la concentration en ethanol (variant entre 50 et 90%) et la frequence (variant entre 28 et 56 kHz). ResultatsLes resultats ont montre que les conditions optimales d'extraction EAU des composants phenoliques totaux sont les suivantes: 15 min de temps d'extraction, 60 degrees C de la temperature d'extraction, 70% de concentration d' ethanol, 56 kHz de la frequence ultrasonore et un: rapport 1:50 solide/solvant. Dans des conditions optimales, le taux des composes phenoliques extrait etait de 55,34 mg / g, et le rendement de l'extrait brut de P. emblica etait a 56,82%. Les resultats revelent que le rendement en composes phenoliques de l' EAU (56,82%) est superieur a celui de l'extraction par solvant classique (16,78%). En outre, les activites antioxydantes des extraits d'ethanol obtenus par les EAU ont ete evaluees en termes d'inactivation des radicaux DPPH,d'activite antioxydante totale, d'activite de chelation de metal, et de potentiel redox. Les extraits de P. emblica obtenus par les EAU ont montre une activite antioxydante elevee (26,00 pg / ml, 50,11 pg / ml et 115,91 mg / mL (valeurs IC50 pour les radicaux DPPH, capacite antioxydante totale et la capacite de chelation des ions ferreux respectivement). ConclusionLe resultat de cette etude a montre que l'Extraction Assistee par Ultrason (EAU) etait un procede approprie pour l'extraction de composes phenoliques totaux. En outre, la conclusion principale de ce travail est le fait que les composes phenoliques du P. emblica presentent une excellente activite antioxydante dans les systemes multi- test.