Volatile Compounds of Asphodelus microcarpus Salzm. et Viv. Honey Obtained by HS-SPME or USE and Analyzed by GC/MS

Chemical analysis of Asphodelus microcarpus Salzm. et Viv. honey is of great importance, since melissopalynology does not allow the unambiguous determination of its botanical origin. Therefore, the volatile compounds of eight unifloral asphodel honeys have been investigated for the first time. The honey extracts were obtained by headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) and analyzed by GC and GC/MS. In the honey headspace, 31 volatile compounds were identified with high percentages of 2-phenylacetaldehyde (2; 14.8-34.7%), followed by somewhat lower percentages of methyl syringate (1; 10.5-11.5%). Compound 2 is not a specific marker of the botanical origin of the honey, but its high percentage can be emphasized as headspace characteristic of asphodel honey. The extraction solvent for all the samples was selected after extracting a representative sample with pentane, Et 2O, pentane/Et 2O 1 : 2 (v/v), and CH 2Cl 2. Compound 1 was the major constituent of all the USE extracts (46.8-87.0%). According to these preliminary results, all the honey samples were extracted by USE with the solvent pentane/Et 2O 1 : 2. A total of 60 volatile compounds were identified with 1 as predominant compound (69.4-87.0%), pointing out 1 as Asphodelus honey volatile marker

Headspace, volatile and semi-volatile patterns of Paliurus spina–christi unifloral honey as markers of botanical origin

The samples of unifloral Paliurus spina-christi honey were analysed by means of headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) followed by gas chromatography and mass spectrometry (GC, GC-MS) in order to obtain complete patterns of headspace, volatile and semi-volatile compounds. In headspace pattern the most abundant compounds and possible markers were nonanal, four isomers of lilac aldehyde, decanal, methyl nonanoate, hexanoic and 2-ethylhexanoic acids. Although the main components of USE extracts were higher saturated aliphatic hydrocarbons, higher aliphatic alcohols and acids, they can not be considered reliable biomarkers due to their probable origin from bee wax or bee cuticle. Although present in small quantities, the more reliable markers in the extracts were benzene derivatives (particularly 4-hydroxy-3,5-dimethylbenzaldehyde, 4-hydroxybenzoic acid and 4-methoxybenzoic acid) along with lower aliphatic acids (butanoic, hexanoic, octanoic and nonanoic)