Modern approaches to characterise the quality of Propolis

Propolis is a natural resinous material. It is used in folk medicine, in cosmetology and in food industry for health foods and nutrition supplements and claimed to improve human health and prevent diseases. In Germany there are also authorized traditional medicinal products. For many parts of Europe Populus species are the main sources of propolis. Our research project addresses characterisation of the quality of propolis and products derived thereof by recent analytical and molecular biological methods in order to analyse and compare samples of different origin. Characterisation of quality is based on HPLC, GC and MS techniques [1] as well as metabolomic approaches by NMR-fingerprint in combination with Principal Component Analysis. An alternative characterisation is performed by sequencing of ITS-regions of DNA isolated from propolis samples to identify the plant species from which samples are originating. PCR-related techniques are also a promising tool to retrace the origin of propolis products. In selected samples from Germany DNA from Populus and Betula species were identified whereas in a commercial sample of green Brazilian propolis DNA from Baccharis dracunculifolia was identified [2]. Chemical profiling and NMR-fingerprinting of studied samples of different origins displayed significant differences, e.g. quality and quantity of aromatic and aliphatic acids and esters, flavonoids etc. The application of such modern analytical techniques is necessary to characterise complex products like propolis and to guarantee a reproducible quality for a safe and adequate use of propolis products. The antimicrobial activities of all studied samples will be evaluated as well.

References: 1. Popova et al.(2009) Phytochem. 70 (10), 1262–1271.

2. De Moura SA et al. (2009) eCAM 10: 1–9.