Gutiérrez Novillo, María Augusta. (2016). Extracción e identificación de los compuestos fenólicos con actividad antioxidante en subproductos agroindustriales de guayaba (Psidium Guajava L.) variedad pera rosada

Abstract

In the present study was analyzed the antioxidant activity of byproducts guava (Psidium guajava L.). Were obtained lipophilic and hydrophilic extracts with different solvents (hexane, ethanol and methanol) and two methods of extraction (soxhlet: 5 hours and dynamic maceration: 3, 6 and 24 hours). The extracts were analyzed for extraction yield, antioxidant activity (ABTS, DPPH, FRAP), total phenol content and quantitation of phenolic compounds and carotenoids by HPLC. The best yield was 13.31% extraction using ethanol for 24 hours. According to antioxidant activity best results were for ABTS: 43.32 µmol TE/g BH with methanol to 6 hours, DPPH and FRAP with methanol and 24 hours: 39.87 y 27.89 µmol TE/g BH respectively, for total phenols: 273.39 mg EAG/100g BH with ethanol to 24 hours. Some phenolic compounds in the hydrophilic fraction were gallic acid: 112.78 mg AG/100 g BH; quercetin; 26.22 mg quercetin/100 g BH and transcinámico acid: 5.44 mg AT/100 g BH. In the lipophilic fraction β-carotene was determined, with the best value extraction β-carotene 5.21 mg/100g.