Headspace analysis and characterisation of South African propolis volatile compounds using GCxGC–ToF–MS

In this study, the headspace volatiles of propolis (n = 39) collected from various locations in South Africa (Gauteng, Northern Cape and Western Cape Provinces) were explored for the first time using GCxGC – ToF – MS. Several GCxGC parameters were optimised including; incubation time, temperature and modulation period. Multivariate data analysis techniques (principal component and hierarchical cluster analyses) were applied on the GCxGC – ToF – MS data to investigate trends and clustering patterns within propolis samples. The results demonstrated that headspace volatiles of propolis varied between locations. The volatile profiles were dominated by monoterpenes such as α -pinene (1.2 – 46.5%), β -pinene (2.0 – 21.8%), dihydrosabinene (trace-17.8%), limonene (trace-11.6%), p-cymene (0.1 – 5.3%), 1,8-cineole (0.1 – 11.0%), 2,7-dimethyl-3-octen-5-yne (trace-11.7%), E- β -ocimene (trace-17.8%), octanal (trace-12.9%), styrene (trace-13.5%) and α -thujene (trace-11.0%). Principal component analysis revealed chemical variation within propolis from the various locations. The heatmap of the averages revealed dehydrosabinene, isopropentyltoluene, p-cymene, acetophenone and α -thujene as chemical markers for the Northern Cape propolis, while λ -terpinene, propanoic acid, furfural, 2-methoxy benzyl alcohol and hexanoic acid methylester were filtered out as markers for Gauteng propolis. The propolis samples originating from the Western Cape Province were dominated by ...
Source: Revista Brasileira de Farmacognosia - Category: Drugs & Pharmacology Source Type: research