Investigation of chemical keys for relationship between plants and their unifloral honeys by hydrodistillation and SPME and biological activities of honeys.

摘要

Volatile compounds of unifloral honeys and their plants essential oils obtained by hydrodistillation (EOH) and solid phase micro extraction (EOS) methods were investigated and compared with each other for the first time. The results exhibited presence of volatile compounds of plant such as o-cymene and carvacrol in Thymus, cis-linalool oxide in Citrus, aliphatic hydrocarbons in Citrus and Astragalus and hexadecanoic acid (palmitic acid) in Astragalus and Medicago honeys. The amounts of terpenes were decreased by increasing molecular weight in EOS, while this pattern does not occur in EOH. Total phenols and antioxidant activities were increased from Citrus to Thymus honey (Citrus < Medicago < Astragalus < Thymus). In antibacterial assay, Thymus honey showed the most potential inhibition to all the experimented strains of bacteria. Increase in phenol content may be an effective factor for antibacterial activity of honey against Escherichia coli, Staphylococcus aureus and Bacillus subtilis. It seems that active compounds with antioxidant properties were responsible for growth inhibition effect on E. coli and S. aureus.