The Phytochemical Screening, Total Phenolic Contents and Antioxidant Activities in Vitro of White Oyster Mushroom (Pleurotus Ostreatus) Preparations

BACKGROUND: The popular commercially cultivated Pleurotus ostreatus mushroom contains very high nutrients and bioactive compounds with high antioxidant activity. The ethanolic extract seems to be the most active in preparation. AIM: This study has an aim to compare the phytochemical analysis of a fresh, dry and ethanolic extract of Pleurotus ostreatus, to measure the total phenolic content and antioxidant activities in vitro of ethanolic extracts of Pleurotus ostreatus. METHODS: The fresh plant’s materials (FPM), dry plants materials (DPM), ethanolic extracts were macerated with 70% (EE70) and 96% ethanol (EE96) of Pleurotus ostreatus which were used for phytochemical analysis, and EE96 was used for antioxidant activity in vitro. The phytochemical analysis was conducted using the Dragendorf and Meyer, FeCl3 test, Salkowsky method, Lieberman method, amyl alcohol, foam test and the NaOH reagent. The total phenol test was carried out using the Follin-Ciocalteu method. The antioxidant activity was tested using the ABTS and H2O2 essay. RESULTS: The phytochemical screening showed that the flavonoid, phenolic compounds, tannin, saponin, alkaloids, and steroids were detected in the FPM, DPM, EE70 and also the EE96. The alkaloid, however, was not identified by the Meyer Reagent in the FPM and DPM. The DPM and EE70 seemed to have the highest amount of saponin based on the foam that was formed. Meanwhile, steroids and flavonoids were detected at a higher level in the EE96, based on the strength of visible colour. However, triterpenoid and quinones could not be identified. In the total phenol test, there was an amount of 6.67 μg phenol in a 1 mg extract sample which was equivalent to 1 mg of Gallic Acid. The EE96 has an IC50 of 108.07 μg/mL for ABTS and an IC50 reduction of 229.17 μg/mL. The process of Pleurotus ostreatus drying did not reduce the content of active substances. The polar active substances seem to be more soluble in the EE70 than the EE96. CONCLUSION: The higher the bioactive substances in the preparation, the more significant the bio-therapeutic effects. Ethanolic extract of Pleurotus ostreatus has a phenol content and a good antioxidant action.