Carina Tikkanen-Kaukanen

Extracts of five organic and one conventional honey sources, available in Finnish markets, were tested for antimicrobial activity and inhibitory concentrations against Escherichia coli, Salmonella Typhi, Pseudomonas aeruginosa, Klebsiella pneumoniae, Bacillus cereus, and Staphylococcus epidermidis, obtained from human specimens. Five (honeys A, B, D, E, F) of the six studied honeys were organic. All the studied honeys had inhibitory activity (zone of inhibition (ZI) > 9.4 ± 0.5 mm) compared to control artificial honey (ZI < 8 mm) against all the studied pathogens. Four organic honeys (B, D, E, F) showed inhibitory activity with ZI > 13.3 mm against all the studied bacteria with minimal inhibitory concentration (MIC) values of 12.5–50%. Against E. coli, the organic honeys E and F had activity index (AI) of 0.64 and 0.73, respectively, compared to the antibiotic AI of 1.0. Against S. Typhi, the organic honeys D and F had AI of 0.59 and 0.64, respectively. Against P. aeruginosa, the organic honeys D, E, and F had the highest AI of 0.71–0.80, and against S. epidermidis the honeys B, D, E, and F possessed relatively high AI of 0.60, 0.67, 0.73, and 0.78, respectively. Against K. pneumoniae and B. cereus, the detected AI of the organic honeys B, D, E, and F varied between AI of 0.48 and 0.58. The organic honey A and conventionally produced honey C possessed only minor activity with MIC values of 80%. Here, we show that commercially available culinary organic honeys possess remarkable antimicrobial activity against several important human bacterial pathogens.

Purpose: Safety data on commonly used herbal medicinal products (HMPs) and marketed in Ghana is scarce. We assessed the sub-chronic toxicity of three most-patronized commercial antimalarial HMPs in Kumasi, Ghana. Method: Top-three HMPs (designated HPA, HPB and HPC) were selected after a mini-survey and sub-chronic toxicity evaluation conducted in accordance with OECD 407 guidelines. Control rats received clean water while test groups received daily adult human dose (DAHD), 5xDAHD or 10xDAHD of either HPA, HPB or HPC for 30 days. Rats were sacrificed on day 31 to obtain biochemical, haematology and histology samples for analysis. Data were analysed by one-way ANOVA and post hoc Turkey’s test. Results: The three HMPs produced alterations in liver morphology predominantly characterized by prominent foci of fatty changes, scattered hepatocytes with intracytoplasmic fat globules and congested central veins and sinusoids. Delicate alveolar with evidence of inflammation and foci of sloughing within rat airway were observed. Alveolar spaces were obscured by debris and inflammatory cells. HPA and HPC produced scattered intensely congested heart vessels while HPB(10) produced haemorrhage and amorphous exudates. All HMPs produced neither treatment-related deaths nor significant change in haematological and biochemical parameters, except for HPA and HPB which decreased (p<0.05) AST and HPB which elevated (p<0.05) FBG. Conclusion: Data from this study suggest the potential of the herbal products, HPA, HPB and HPC, to cause major organ-system dysfunction or damage. We advise cautious use of these products and recommend further safety evaluation in chronic toxicity models.

Purpose To address the question of whether users of herbal products (HPs) are exposed to harmful contaminants, we evaluated six HPs mostly patronized in Kumasi for heavy metal contamination and assessed the health risk associated with their use. This study is one of the first safety evaluation studies on finished multiherbal products in the region. Method Three antimalarial, two antidiabetic and one antihypertensive HPs were selected after a mini-survey and coded randomly as HP A-F. The HPs were acid digested for quantitative analysis of heavy metals using Inductively Coupled Plasma Mass Spectrometer. Hg quantification was carried out using cold vapour atomic absorption spectroscopy. Results The cancer risk estimation values for the carcinogenic metals ranged between 1.54 × 10⁻⁹ to 3.73 × 10⁻⁴ and were all within acceptable limits. The non-cancer health risk evaluation revealed that, some of the products pose health risk to consumers. The estimated daily intake (EDI) for As in HPF was 2.48 × 10⁻⁴ mg/kg/day compared to the reference limit of 1.67 × 10⁻⁴ mg/kg/day. HPF also had high hazard index (HI) of 5.70 (HI >1) in children as compared to 1.68 (HI >1) in adults showing a 3.4 folds increase in the health risk among the former. Conclusion The six polyherbal products exhibited carcinogenic risk within acceptable limits. Although, the non-carcinogenic risk assessment of products HPA to HPE suggests safety, this can only be ascertained after further characterization of their health risks in detailed chronic toxicity studies. The high HI for product HPF suggests health risk for consumers of this product.

Epidemics of meningococcal meningitis cause significant health problems especially in Sub-Saharan Africa. Novel anti-infective candidates are needed. In modern anti-adhesion therapy initial attachment of bacteria to host cells is prevented. Our unique studies have revealed anti-adhesive candidates from natural products, namely milk and berries, against Neisseria meningitidis adhesion. In the present study against N. meningitidis adhesion, a novel binding inhibitor was found; salvianolic acid B (SA-B), a polyphenol from the radix Salviae miltiorrhizae, an important part of Chinese folk medicine. In order to test inhibition of meningococcal pili binding and anti-adhesion activity of SA-B, bovine thyroglobulin, a reference glycoprotein for meningococcal receptor was used in a microtiter plate assay. Inhibitory activity was tested by using serial dilutions of SA-B extracts of 98 and 70 % purity. Results were confirmed in a HEC-1B cell dot assay and antimicrobial activity was measured by using a microbroth dilution assay. Almost total (93 %) inhibition of pili binding, anti-adhesion, was achieved with the 70 % extract of SA-B at the concentration of 0.3 mg/mL in the bovine thyroglobulin reference model. 50 % binding inhibition activity was achieved with 0.6 µg/mL of the SA-B extract. Total inhibition of the pili binding to HEC-1B cells was found at the tested concentration of 0.5 mg/mL. The 98 % pure SA-B resulted in weaker inhibition. At the concentration of 0.3 mg/mL 78 % inhibition was achieved in the thyroglobulin model. For 50 % inhibition 2.4 μg/mL of pure SA-B was needed. The difference between the binding inhibition activities (70 and 98 % pure SA-B) was statistically significant (P = 0.03). Antimicrobial activity of 70 % SA-B, when investigated against N. meningitidis, was detected only in relatively high concentrations. Our results indicate that plant SA-B may prevent meningococcal infections by inhibiting meningococcal binding and may thus have an impact on the amount of nasopharyngeal carriers of N. meningitidis. This may prevent the spreading of meningococcal infections between humans. One could conclude that SA-B and its source dried radix S. miltiorrhizae, which is an important part of Chinese folk medicine, could be valuable candidates for further research in meningococcal disease prevention.