Phytochemical analysis and antioxidant activities of ethanol extract of stingless bee propolis from Indonesia

The objective of this study was to evaluate the phytochemical constituents and antioxidant activities of the ethanol extracts of Indonesian stingless bee propolis. The stingless bee propolis was obtained from South Sulawesi, Bintan, and Lampung, and was prepared through maceration with ethanol. The free radical scavenging and antioxidant activity of the extract were assessed against 1,1-diphenyl-2-picrylhydrazyl (DPPH), while the total phenolics and flavonoids were also determined to assess their corresponding effect on the antioxidant activity of the propolis extract. Total phenols and flavonoids contents were analyzed by Folin-Ciocalteu colorimetric and aluminum chloride (AlCl3) methods, respectively. The results showed the ethanol extracts of Indonesian stingless bee propolis containing phytochemical compounds such as phenolic and flavonoid compounds. The antioxidant activity (IC50) ranged from 150.20 to 207.63 mg/L, while total phenols and flavonoids ranged from 152.46 ± 55.61 to 327.86 ± 38.15 mg GAE/g extract and 6.16 ± 1.24 to 17.08 ± 0.53 mg QE/g extract, respectively. Indonesian stingless bee propolis might contain greatly diverse phytochemical compounds and antioxidant activities.