Comparative Analysis of Antioxidant Properties in Water and Ethanolic Extracts of Propolis from Two Species of Indo-Malayan Stingless Bee

Propolis, an organic material crafted by bees from a blend of their salivary secretions, beeswax, pollen, and resins, contains essential organic compounds. Phenolic and flavonoids, crucial for their antioxidant properties, are prominently present in this resinous substance. The antioxidant capabilities of propolis extract from Geniotrigona thoracica (G) and Heterotrigona itama (H), two species of Indo-Malayan stingless bees, were examined in this study by using different solvents (ethanol, E and water; W). The analysis involved four extracts of stingless bee propolis which included the ethanolic extract of G. thoracica and H. itama (GE and HE), and water extract of the two species (GW and HW). The Folin-Ciocalteu method evaluated total phenolic content (TPC), while colourimetric techniques were utilised for total flavonoid content (TFC) estimation. Additionally, antioxidant strength was assessed through ferric-reducing antioxidant power (FRAP) as well as IC50 values from the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. The findings confirmed that HE offered the most elevated values for both TPC and TFC, with 52.775 mg GAE g-1 and 467.37 mg QE g-1, respectively. Meanwhile, the IC50 value was comparable among HE and GE at 0.351 and 4.536 mg/ml, respectively, compared to HW and GW (11.985 and 30.93 mg/ml). Consequently, both species are competitive natural sources of antioxidants under the same solvent. While ethanolic extract propolis demonstrates superior antioxidant properties, water extract demonstrates potential benefits, including being consumer-friendly and environmentally sustainable, making it a cost-effective alternative worth exploring. The extract holds promising potential for future applications, including in the cosmeceutical, functional food, and pharmaceutical industries.