Chemical profiling, bioactive compounds, antioxidant, and anti-inflammatory activities of Indonesian propolis extract produced by Tetragonulalaeviceps

Abstract

Propolis produced by stingless bees contains various chemical compounds that contribute to its bioactivity. The availability of certain plants at the growth site and the propolis's geographic origin have a significant impact on its chemical composition. The objective of this study was to examine the chemical profile, yield, total flavonoid and phenolic content, and in vitro antioxidant and anti-inflammatory effects of propolis extract from 10 distinct locations in Indonesia. The yield of propolis extract investigated in this study lies in the range of 26.25 ± 1.76 to 43.25 ± 3.60 %. The total phenolic content of the propolis extract varies from 50.03 ± 3.40–98.03 ± 13.94 mg GAE/g whereas the total flavonoid content of the propolis extract varies from and 0.70 ± 0.08–57.76 ± 0.67 mg QE/g. The antioxidant activity of the propolis extract in terms of IC50 values lies in the range of 332.07 ± 6.12 to 831.48 ± 29.48 ppm whereas the anti-inflammatory activity of the propolis extract in terms of IC50 values lies in the range of 28.69 ± 4.95 to 44.12 ± 19.22 ppm. Both the total flavonoid and phenolic content of the propolis extract from various locations were correlated with the antioxidant activities and anti-inflammatory activities. The results indicate that there was a significant negative correlation between the total flavonoid and phenolic content of the propolis extract with the antioxidant activity. However, the anti-inflammatory activity was not strongly correlated with the total flavonoid and phenolic content of the propolis extract. There were 36 volatile compounds in the propolis extract as identified by the Gas Chromatography–Mass Spectrometry with triterpenoid as the major substances (28.66–44.86 %). The presence of anti-inflammatory compounds particularly α, β-Amyrin (2.2–6.52 %) and lupeol (2–4.72 %) in the propolis extract highlights the potential of propolis in health and medicine application.