IN-VITRO EVALUATION OF NITRIC OXIDE INHIBITORY ACTIVITY AND PHYTOCHEMICAL SCREENING OF Heterigona itama PROPOLIS

The therapeutic benefits of propolis have been known and utilised since ancient times. Heterotrigona itama is the most abundant stingless bee in Peninsular Malaysia and in this study, its propolis was subjected to successive maceration extraction methods with different solvents. The chemical composition of propolis solvent fractions was then evaluated using phytochemical screening analysis. After that, the fractions were assessed for Total Phenolic Content (TPC) and Total Flavonoid Content (TFC) before being subjected to Nitric Oxide (NO) assay to determine their anti-inflammatory potential. The most active fraction in the NO assay was then selected to determine its cytotoxicity on RAW 264.7 macrophage cells. In phytochemical screening analysis, thin-layer chromatography showed the presence of flavonoids in the Methanol Fraction (MFR). The TPC and TFC results showed that MFR had the highest content of phenolics and f lavonoids, which was 54.093 ± 0.003 µg/mL and 30.15 ± 0.003 µg/mL, respectively. The MFR was also non-toxic and could increase the proliferation of RAW 264.7 cells. The MFR possessed moderate anti-inflammatory properties as demonstrated with IC50 values of 82.87 µg/mL and 92.31 µg/ml in NO-inhibitory activity and cell-based assays, respectively, compared to other fractions.