Determination of Antioxidant Activity, Total Phenolic and Flavonoid Contents of Malaysian Stingless Bee Propolis Extracts

Abstract

This study aims to determine the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of ethanolic extract propolis (EEP) and water extract propolis (WEP) derived from six Malaysian stingless bee species. The TPC and TFC were measured by Folin-Ciocalteu colorimetric and aluminium chloride methods, respectively. The antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. The results indicated that EEP of Geniotrigona thoracica had the highest TPC and TFC at 259.84 ± 4.97 mg/g GAE and 435.00 ± 6.57 mg/g QE, respectively. Similarly, EEP of G. thoracica exhibited the greatest free radical scavenging activity with the percentage of inhibition at 88.00 ± 13.34% and IC50 of 104.20μg/mL. Antioxidant activity was highly correlated with TPC (R2 = -0.744, p < 0.05) whereas no correlation was observed between TFC and antioxidant activity. This study indicates that the antioxidant property of the propolis extract may be influenced by elevated levels of phenolic content. In conclusion, ethanolic extract of G. thoracica is the greatest source of antioxidants among the six tested Malaysian stingless bee propolis and this suggests that the extract may serve as a promising source of antioxidant agent.

GC-MS Analysis and Antibacterial Activity of Ethanolic and Water Extracts of Malaysian Heterotrigona itama Propolis Against Selected Human Pathogenic Bacteria

“…Studies have shown that the antibacterial activity of propolis corresponds to its polyphenolic compounds such as phenolic acid and flavonoids (Abdelrazeg et al, 2020). Furthermore, Adli et al (2022) demonstrated that the EEP of H. itama possessed higher total phenolic and flavonoid contents compared to WEP. Similar findings were reported by Kubiliene et al (2015) and Abdullah et al (2019) who indicated that propolis extracted using alcohol and methanol yielded better antimicrobial activity compared to water extract propolis.…”

“…The colonies were housed in wooden nest boxes under the shade with predominant vegetation consisting of Lamiaceae, Myrtaceae, Rubiaceae, Fabaceae, Lythraceae, Scrophulariaceae, Elaeocarpaceae, Sapindaceae, Moraceae, and Anacardiaceae. The stingless bee species was identified by an entomologist from the Centre for Insect Systematics (CIS), Universiti Kebangsaan Malaysia with the accession number CIS-TRI-2022-02 (Adli et al, 2022). The propolis sample was collected by scraping the inside of the hives using a clean stainless-steel spatula.…”

Comparative Methods to Evaluate the Antioxidant Capacity of Propolis: An Attempt to Explain the Differences

“…On the other hand, the presence of FLAV compounds in propolis samples can positively influence the quantification of TPC in all tested methods. Several works show that there is a positive correlation between TPC and flavonoid content [ 60 , 61 ]. However, no comparative work has been found relating TPC to HBA and HCA content.…”