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Propolis is a generic name for a biological substance produced by bees used for multiple purposes in folk medicine. Propolis special extract GH 2002 is crude propolis highly purified by a special procedure and freed from the accompanying substances like pollen, wax, resins. The cytotoxic and antiherpetic effect of propolis extracts against Varicella zoster virus (VZV) was analysed in cell culture, and revealed a moderate cytotoxicity on lung fibroblasts with a CC50 of 380 µg/ml. The 50 % inhibitory concentration (IC50) of GH 2002 propolis extract for VZV plaque formation was determined at 64 µg/ml. The propolis extract exhibited high levels of antiviral activity against VZV in viral suspension tests, infectivity was significantly reduced by 93.9 % and a direct concentration-dependent antiviral activity could be demonstrated. In order to determine the mode of virus suppression by propolis, the extract was added at different times during the viral infection cycle. Addition of propolis to uninfected cells (pretreatment cells) prior to infection or to infected cells (replication) during intracellular replication had no or only minor effect on virus multiplication. However, propolis exhibited high anti-VZV activity when viruses were pretreated with propolis prior to infection thus indicating an unspecific interaction between the virus and propolis. The antiviral activity is comparable to acyclovir.

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The need to discover and develop alternative therapies to treat multidrug-resistant bacterial infections is timely. The aim of this study was to examine the antimicrobial potential of propolis, as a purified and concentrated special extract GH 2002, against clinical isolates of Streptococcus pyogenes, methicillin-resistent Stapylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium (VRE) and Candida. Minimal inhibitory concentrations (MICs) and minimal microbicidial concentrations (MMCs) of propolis against microbial pathogens were evaluated using the broth microdilution method. Propolis extract GH 2002 revealed low MICs in the range of 0.03 to 2 mg/ml against S. pyogenes, S. aureus, E. faecium and Candida. A high bactericidal activity of propolis extract in the range of 0.06 to 1.0 mg/ml was determined for S. pyogenes and S. aureus, however propolis was not bactericidal against E. faecium. Propolis concentrations between 0.6 and 2.4 mg/ml displayed fungicidal activity against different Candida species. Whereas all tested MRSA strains were highly susceptible against propolis, only minor activity was found against VRE strains. Time-kill curves demonstrated a high antimicrobial activity at low MICs already after few hours of incubation against reference strains, clinical antibiotic-susceptible strains, clinical antifungal susceptible strains as well as all tested clinical MRSA strains, but not against VRE strains. In conclusion, clinical drug-sensitive as well as some clinical multidrug-resistant microbial isolates, i.e. MRSA, were susceptible to propolis with different degrees of susceptibility. These results suggest that the special propolis extract GH2002 might be used in the development of alternative products for therapy of microbial infections.

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Seven Hawthorn extracts were tested in isolated guinea pig aorta rings. The effect on noradrenaline- (10 microM) induced contraction was investigated. The extracts were prepared using ethanol (40 to 70% v/v), methanol (40 to 70% v/v), and water as the extraction solvents. The aqueous-alcoholic extracts displayed similar spectra of constituents. They were characterised by similar procyanidin, flavonoid, total vitexin and total phenols content and by similar TLC fingerprint chromatograms. The aqueous extract, however, showed a different fingerprint and a noticeably lower concentration of procyanidins, flavonoids and total phenols but a similar total vitexin content. All 7 extracts had a relaxant effect on the aorta precontracted by noradrenaline and led to relaxations to 44 until 29% of the initial values. The EC50 values of the aqueous-alcoholic extracts varied between 4.16 and 9.8 mg/l. The aqueous extract produced a similarly strong maximal relaxation as the other extracts, but the EC50, at 22.39 mg/l, was markedly higher. The results show that Hawthorn extracts with comparable quality profiles were obtained by using aqueous-alcoholic extraction solvents (40 to 70% ethanol or methanol). The extracts exerted comparable pharmacological effects. When using water as the extraction solvent, both, the spectrum of constituents and the pharmacological effect, deviated remarkably. It is thus possible to obtain bioequivalent extracts with comparable effect profiles by using 40 to 70% ethanol or methanol as the extraction solvent.

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The anti-exudative and anti-edematous effects and the dose-effect relationship of a-sympathomimetics, especially of l-phenylephrine-HCl (PE), have been demonstrated using as model the rat pad-carrageenan edema and the histamine liberator test, the dosage being administered cutaneously, orally, and intraperitoneally. The beta-receptor activating compound bamethane sulfate was not effective when used on the same models. Evidence of percutaneous penetration of PE was provided both on isolated skin and in viro. PE, when injected intravenously or subcutaneously, produced a rise of blood pressure in experimental animals. When PE was administered orally and cutaneously, it did not, however, alter the blood pressure. The anti-inflammatory and anti-exudative effects remianed unchanged.

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The pharmacokinetics of unlabelled and tritium-labelled glycosaminoglycan polysulfate (GAGPS) was examined by gel chromatography, electrophoresis and radiometry. The compound was given i.m. and, for comparison, i.v. In both cases (dose: 7.5 mg/kg) blood levels after 1 h reached maxima of approx. 6 mug/ml and remained between 2.0 and 1.5 mug/ml for between 24 and 48 h. The question of threshold-limited excretion is discussed. The concentration curves of the synovia were almost identical to those of the blood. The cartilage of the joint had a comparable level after 48 h (1.7 mug/g), whilst the level was lower in rib cartilage (1.1 mug/g). Urinary excretion within 24 h amounted to 45% of almost unchanged GAGPS. A further 10% were excreted within the following 24 h. The residue was distributed chiefly in the kidneys, liver, skin, spleen, gut, and bone marrow. In the course of the elimination time the excreted substnace showed a lower molecular weight as was found by gel chromatography.

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