European propolis is highly active against trypanosomatids including Crithidia fasciculata.

Extracts of 35 samples of European propolis were tested against wild type and resistant strains of the protozoal pathogens Trypanosoma brucei, Trypanosoma congolense and Leishmania mexicana. The extracts were also tested against Crithidia fasciculata a close relative of Crithidia mellificae, a parasite of bees. Crithidia, Trypanosoma and Leishmania are all members of the order Kinetoplastida. High levels of activity were obtained for all the samples with the levels of activity varying across the sample set. The highest levels of activity were found against L. mexicana. The propolis samples were profiled by using liquid chromatography with high resolution mass spectrometry (LC-MS) and principal components analysis (PCA) of the data obtained indicated there was a wide variation in the composition of the propolis samples. Orthogonal partial least squares (OPLS) associated a butyrate ester of pinobanksin with high activity against T. brucei whereas in the case of T. congolense high activity was associated with methyl ethers of chrysin and pinobanksin. In the case of C. fasciculata highest activity was associated with methyl ethers of galangin and pinobanksin. OPLS modelling of the activities against L. mexicana using the mass spectrometry produced a less successful model suggesting a wider range of active components

The chemical characterization of Nigerian propolis samples and their activity against Trypanosoma brucei.

Profiling of extracts from twelve propolis samples collected from eight regions in Nigeria was carried out using high performance liquid chromatography (LC) coupled with evaporative light scattering (ELSD), ultraviolet detection (UV) and mass spectrometry (MS), gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). Principal component analysis (PCA) of the processed LC-MS data demonstrated the varying chemical composition of the samples. Most of the samples were active against Trypanosoma b.brucei with the highest activity being in the samples from Southern Nigeria. The more active samples were fractionated in order to isolate the component(s) responsible for their activity using medium pressure liquid chromatography (MPLC). Three xanthones, 1,3,7-trihydroxy-2,8-di-(3-methylbut-2-enyl)xanthone, 1,3,7-trihydroxy-4,8-di-(3-methylbut-2-enyl)xanthone a previously undescribed xanthone and three triterpenes: ambonic acid, mangiferonic acid and a mixture of α-amyrin with mangiferonic acid (1:3) were isolated and characterised by NMR and LC-MS. These compounds all displayed strong inhibitory activity against T.b.brucei but none of them had higher activity than the crude extracts. Partial least squares (PLS) modelling of the anti-trypanosomal activity of the sample extracts using the LC-MS data indicated that high activity in the extracts, as judged from LCMS 2data, could be correlated to denticulatain isomers in the extracts

Chemical and antimicrobial profiling of propolis from different regions within Libya.

Extracts from twelve samples of propolis collected from different regions of Libya were tested for their activity against Trypanosoma brucei, Leishmania donovani, Plasmodium falciparum, Crithidia fasciculata and Mycobacterium marinum and the cytotoxicity of the extracts was tested against mammalian cells. All the extracts were active to some degree against all of the protozoa and the mycobacterium, exhibiting a range of EC50 values between 1.65 and 53.6 μg/ml. The toxicity against mammalian cell lines was only moderate; the most active extract against the protozoan species, P2, displayed an IC50 value of 53.2 μg/ml. The extracts were profiled by using liquid chromatography coupled to high resolution mass spectrometry. The data sets were extracted using m/z Mine and the accurate masses of the features extracted were searched against the Dictionary of Natural Products (DNP). A principal component analysis (PCA) model was constructed which, in combination with hierarchical cluster analysis (HCA), divided the samples into five groups. The outlying groups had different sets of dominant compounds in the extracts, which could be characterised by their elemental composition. Orthogonal partial least squares (OPLS) analysis was used to link the activity of each extract against the different micro-organisms to particular components in the extracts

The Chemical and Biological Properties of Propolis

The term propolis comes from two Greek words, pro (which means for or in defence of) and polis (which means the city); thus, propolis means in defence of the city or beehive. Propolis is a sticky resinous substance, which is gathered from buds and the bark of trees. It is also known as "bee glue" as bees use it to cover surfaces, seal holes and close gaps in their hives, thus providing a sterile environment that protects them from microbes and spore-producing organisms, including fungi and molds. It can be considered to be a potent chemical weapon against bacteria, viruses, and other pathogenic microorganisms that may invade the bee colony. Also, bees use propolis as an embalming substance, to mummify invaders such as other insects, that have been killed and are too heavy to remove from the colony. Thus, propolis is important for bee health but it also has activity against many human diseases. It is a powerful anti-oxidant and can modulate the activity of reactive oxygen species within the human body. The most studied aspect of propolis is its anti-bacterial activity, which is almost always present at a moderate to high level depending on the exact type of propolis. It is in general more active against Gram positive than Gram negative bacteria, but activity against Gram negative bacteria has been observed. Propolis has been found to be active against a range of viruses and also is almost always active against protozoa such as Tryanosoma brucei and Leishmania donovani. Propolis also shows activity against cardiovascular diseases and diabetes and has immunomodulatory effects. Anti-cancer activity has also been observed. In summary, propolis is remarkable for its range of biological activities and for the variety of its chemical composition. It may be of great importance both to bees and humans