Investigation of Antioxidant and Anticholinesterase Potential of Essential Oil and Methanolic Extract of Propolis from Mila Region

GC-MS based metabolic profile and toxicological evaluation of three Algerian propolis

This study aimed to investigate the chemical composition and toxicity of methanolic extracts of three Algerian propolis collected from Oum el Bouaghi (MEPO), El Harrouch (MEPH) and Collo (MEPC) regions. The chemical profile was characterised by GC-MS. The toxicity of the extracts was tested using brine shrimp model. The GC-MS analysis revealed the presence of ferulic acid (23.8%), pinostrobin chalcone (15.8%) and α-eudesmol (11.3%) as major compounds in MEPO, pinostrobin chalcone (22.2%), 9-octadecenoic acid, methyl ester, (E)- (17.4%), and γ-gurjunenepoxide-(2) (11.7%) were the most abundant components in MEPH, whereas MEPC was dominated by 1-heptatriacotanol (17.8%), pinostrobin chalcone (14.7%), totarol (13.7%) and 9-octadecenoic acid, methyl ester, (E)- (13.0%). The brine shrimp lethality test indicated that the extracts had moderate toxicity in which MEPC exhibited the highest activity with LC50 of 201.61 ± 7.27 µg/mL. All extracts showed no toxicity at 25 µg/mL concentration and below.

Correlation between total phenolic and flavonoid contents and biological activities of 12 ethanolic extracts of Iranian propolis

Propolis is a resinous substance produced by honey bees that is very popular as a natural remedy in traditional medicine. The current research is the first study on the biological properties of ethanolic extracts of propolis (EEP) from several different regions (12) of Iran. Total phenolic and flavonoid contents (TPC and TFC) of Iranian EEPs were variable between 26.59-221.38 mg GAE/g EEP and 4.8-100.03 mg QE/g EEP. The DPPH scavenging assay showed all the studied EEP samples, except for the sample with the lowest TPC and TFC (P6), have suitable antioxidant activity. All the EEPs inhibited both cholinesterase enzymes (acetylcholinesterase: AChE, butyrylcholinesterase: BuChE) but most of them exhibited a distinct selectivity over BuChE. Evaluation of the antibacterial activity of the EEP samples using four pathogenic bacteria (B. cereus, S. aureus, A. baumannii, and P. aeruginosa) demonstrated that the antibacterial properties of propolis are more effective on the gram-positive bacterium. Spearman correlation analysis showed a strong positive correlation between TPC and TFC of the Iranian EEPs and their antioxidant, anticholinesterase, and antibacterial activities. Considering that there is ample evidence of anticholinesterase activity of flavonoids and a significant correlation between the anticholinesterase activity of the studied Iranian EEPs and their total flavonoid content was observed, the interaction of 17 well-known propolis flavonoids with AChE and BuChE was explored using molecular docking. The results indicated that all the flavonoids interact with the active site gorge of both enzymes with high affinity. Summing up, the obtained results suggest that Iranian propolis possesses great potential for further studies.

Can Propolis Be a Useful Adjuvant in Brain and Neurological Disorders and Injuries? A Systematic Scoping Review of the Latest Experimental Evidence

Propolis has been used therapeutically for centuries. In recent years, research has demonstrated its efficacy as a potential raw material for pharmaceuticals and nutraceuticals. The aim of the present scoping review is to examine the latest experimental evidence regarding the potential use of propolis in protecting the brain and treating neurological disorders and injuries. A systematic scoping review methodology was implemented. Identification of the research themes and knowledge gap was performed. After applying the exclusion criteria, a total of 66 research publications were identified and retrieved from Scopus, Web of Science, Pubmed, and Google Scholar. Several key themes where propolis is potentially useful were subsequently identified, namely detoxification, neuroinflammation, ischemia/ischemia-reperfusion injury/traumatic brain injury, Alzheimer's disease, Parkinson's disease, and epilepsy models, depression, cytotoxicity, cognitive improvement, regenerative medicine, brain infection, and adverse effects. In conclusion, propolis is shown to have protective and therapeutic benefits in alleviating symptoms of brain and neurological disorders and injuries, demonstrated by various in vitro studies, animal models, and human clinical trials. Further clinical research into this area is needed.

Chemical composition, antioxidant, and antimicrobial activities of two essential oils from Algerian propolis

This study aims to investigate the chemical composition, antioxidant, and antimicrobial activity of two essential oils (EOs) from Algerian propolis. The volatile constituents were analyzed by gas chromatography-mass spectrometry. Fifty components were identified from the oils. The major components were found to be: cedrol (17.0%), β-eudesmol (7.7%), and α-eudesmol (6.7%) in EO of propolis from Oum El Bouaghi (EOPO) whilst α-pinene (56.1%), cis-verbenol (6.0%), and cyclohexene,3-acetoxy-4-(1-hydroxy-1-methylethyl)-1-methyl (4.4%) in EO of propolis from Batna (EOPB). The antioxidant properties of EOPO and EOPB were determined using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS•+) and cupric reducing antioxidant capacity (CUPRAC assays), respectively. Both EOs had more cupric ion reducing ability than scavenging ABTS•+ radicals. The antimicrobial potential of the two EOs against eight pathogens was assayed by the agar diffusion method and the mode of action was determined by microdilution assay. The results revealed that EOPB was bactericidal for all tested pathogenic bacteria and fungicidal for Candida albicans ATCC 10231, whereas, EOPO showed bacteriostatic effect against Escherichia coli O157:H7 and Pseudomonas aeruginosa ATCC27853 and fungistatic effect against C. albicans ATCC 10231. Thus, the obtained results suggest the important use of propolis EOs as preservative agents.