Antioxidant and antimicrobial properties of Thai propolis extracted using ethanol aqueous solution

Abstract

Summary The potential of using propolis collected from Thailand as a natural antioxidant and antimicrobial agent for food applications was investigated. The propolis extract was prepared by using different ethanol aqueous solutions, including 30%, 40%, 50% and 70%. Total phenolic content (TPC), phenolic compound and antioxidant activity of the propolis were determined using Folin–Ciocalteau method, high performance liquid chromatography (HPLC) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity, respectively. The antimicrobial ability was tested against Staphylococcus aureus (TISTR 118), Salmonella enteritidis (DMST 17368), Escherichia coli (TISTR 780) and Pseudomonas aeruginosa (ATCC 27853) using disc diffusion technique. The major phenolic compounds found in Thai propolis were rutin, quercetin and naringin. The TPC and DPPH radical scavenging activity increased with increasing ethanol concentration in the solvent. Propolis extract showed antimicrobial activity, in terms of inhibitory zone for S. aureus and limited growth underneath paper discs, against all tested bacteria.

Predictive mathematical modeling for EC50 calculation of antioxidant activity and antibacterial ability of Thai bee products

“…The TPC of our propolis (237.18 mg GAE/g sample) agreed with values obtained by Ahn et al (2004) in Korean propolis (85-283 mg GAE/g) and by Moreira et al(2008)in Portuguese propolis (151-329 mg GAE/g). However, the TPC of our propolis was higher than the values reported by Siripatrawan et al(2013) and Kumazawa et al(2004)in Thai propolis,22.8-77.5 mg GAE/g and 31.2 mg GAE/g, respectively, and Choi et al (2006) in Brazilian propolis (120 mg GAE/g). On the other hand, the TPC of Chinese propolis showed slightly higher values as ranged from 262 to 299 mg GAE/g .…”

“…In this research, we used the procedure based on the reduction of DPPH and ABTS, stable free radicals, to investigate the free radical-scavenging activity of the bee products. The DPPH and ABTS assay has been widely employed to determine the free radical scavenging ability of a variety of natural antioxidants (Chen et al, 2013;Lachman et al, 2010;Siripatrawan et al, 2013).The underlying mechanisms of determining the activity using DPPH and ABTS can be represented as Reaction 1 and 2, respectively (Boligon et al, 2014):…”

“…The antimicrobial activity of chemical compounds, including antibacterial, antifungal and antiviral activity, is important against infections incited by microorganisms (Bogdanov, 2011). Plant polyphenols are potential natural alternatives to synthetic antioxidant and antimicrobial compounds (Siripatrawan et al, 2013). Bee products, one of the essential sources of polyphenols, are well known in traditional medicine dating back to ancient times.…”

“…Propolis contains more than 300 constituents such as polyphenols, sesquiterpene quinones, coumarins, steroids, amino acids, and inorganic compounds (Choi et al, 2006;Siripatrawan et al, 2013).The composition of propolis varies depending on the season and on the botanical origin from which the plant resins have been collected (Bosio et al, 2000). Propolisis now recognized to have a wide range of biological activities, such as antibacterial, anti-inflammatory, antioxidative, hepatoprotective, and tumoricidal activities (Bosio et al, 2000;Miorin et al, 2003).…”

“…Determination of the antioxidant power of the bee products involved the use of different methods such as the DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS [2,2´-Azino-bis(3-ethylbenzthiazoline-6-sulphonate)], TBARS (thiobarbituric acid reactive substances) and β-carotene bleaching assays (Buratti et al, 2007;Ferreira Isabel et al, 2009;Lachman et al, 2010;Siripatrawan et al, 2013). The DPPH and ABTS assays have been widely used to determine antioxidant activity of various plants and other materials since they are stable free radicals and the determination is simple.…”