Chemical Characterization and in-vitro Antimicrobial Screening of Ethanolic Extract of Propolis Collected from Jazan, Saudi Arabia.

Propolis is a resinous substance produced by honeybees and used to protect their hives from outside attackers including microorganisms. In present study, propolis sample was collected from adjacent to Jazan city, Saudi Arabia and the chemical constituents of the ethanolic extract was evaluated by GC-MS. The ethanolic extract was tested against selected strains of microorganisms for its antibacterial and antifungal activities. The major classes of compounds indentified in the extract were fatty acid esters and aliphatic hydrocarbons. Methyl-(7Z)-7-hexadecenoate, methyl-(9E)-octadecenoate and methyl tetracosanoate were found to be the principal fatty acid esters, while E-pentatriacont-17-ene and 2,4-dimethylpentane were identified as predominant aliphatic hydrocarbon compounds. The propolis extract has exhibited remarkable antimicrobial activity against certain strains of bacteria and yeasts. In general, significant antimicrobial activity was recorded against gram positive bacteria (zone of inhibition: 16.3±0.35–30.6±0.11 mm; MICs: 1–4 μg/ml); while gram negative bacteria (zone of inhibition: 10.1±0.23–17.2±0.13 mm; MICs: 4–16 μg/ml) and yeasts (zone of inhibition: 9.1±0.23–18.7±0.10 mm; MICs: 2–16 μg/ml) showed comparatively lower susceptibility to propolis extract. The antimicrobial potential of propolis extract could be therapeutically significant and may allow substituting for some antimicrobial agents or synergizing the antimicrobial action, when used in combination. [ABSTRACT FROM AUTHOR]