Baccaurea racemosa (Reinw. ex Blume) Müll. Arg. pulp: a potential natural
antioxidant
Baccaurea racemosa (Reinw. ex Blume) Müll. Arg. is a fruit widely grown in Indonesia locally known as ‘kepundung’. Some of genus Baccaurea has potential to be developed as a natural antioxidant. However, the antioxidant activity of B. racemosa pulp has not been published. This study is aimed to (i) explore the antioxidant activity, (ii) measure the total phenolic and flavonoid contents, and (iii) investigate the correlation of antioxidant activity of extract and fractions of B. racemosa pulp with their total phenolic and flavonoid contents. Fresh B. racemosa pulp was macerated with methanol to obtained methanolic extract. The methanolic extract was partitioned using n-hexane followed dichloromethane and ethyl acetate. This study revealed that ethyl acetate fraction has the highest antioxidant activity with the scavenging activity of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-Azinobis(3-etylbenzthiazoline)-6-sulfonic acid (ABTS) with values IC50 127.155±4.311ug/mL and 108.155±6.455 mM trolox equivalent/100 mg dry extract respectively. However, the highest antioxidant activity using β-carotene bleaching (BCB) assay is the methanolic extract with value 36.898±13.240%. Furthermore, the ethyl acetate fraction has the highest total phenolic content (TPC) and total flavonoid content (TFC) with values 42.975±1.978 mg gallic acid equivalent/g dry extract (mg GAE g-1 dry extract) and 122.813±1.604 mg rutin equivalent/g dry extract (mg RE g-1 dry extract) respectively. TPC and TFC of B. racemosa pulp have a significant correlation with ABTS free radical scavenging activity. In this current study, it was discovered that ethyl acetate fraction of B. racemosa pulp can be developed to be a natural antioxidant.