Total phenolic content and in vitro evaluation of antioxidant activity of ethanol extract of Ganoderma amboinense

Abstract

Background: Ganoderma amboinense is rich in fibers, minerals, and vitamins. This antler-shaped mushroom contains various antioxidant compounds called polyphenols and flavonoids. Antioxidants can counteract or deactivate free radicals in plants and animals by turning them into less reactive compounds. The methods of compound extraction are numerous and with different effects on the concentration of active compounds. Hence, selecting a correct extraction method becomes necessary. Aims and Objectives: The aim of this stuidy is to compare two extraction methods, namely, extraction by maceration and Soxhlet extraction, based on the total phenolic contents and the antioxidant activities of the ethanol extracts (96%) of G. amboinense. Materials and Methods: The ethanol extract was obtained from maceration and Soxhlet extraction. The total phenolic content of 96% ethanol extract of G. amboinense was determined using ultraviolet-visible spectrophotometry with Folin–Ciocalteu reagent, while the antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl method. Results: Thin-layer chromatography produces ethanol extracts, from either maceration or Soxhlet extraction, that contain phenolic compounds. The total phenolic contents of the ethanol extracts from maceration and Soxhlet extraction are 26.72 ± 1.13 mg gallic acid equivalents (GAE)/g of extract and 23.27 ± 1.07 mg GAE/g of extract, respectively. The effective scavenging 50% values of gallic acid and ethanol extract are, respectively, 2.476 μg/ml and 197.6 μg/ml. Conclusion: Maceration produces ethanol extract of G. amboinense with higher total phenolic content than Soxhlet extraction. The research findings indicate that the ethanol extract has in vitro antioxidant activity.