Safety And Antimicrobial Activities Of Herbal Materials Used In Management Of Oral Health By Traditional Medical Practitioners In Nairobi County, Kenya

ABSTRACT

The use of herbs for treatment and management of oral diseases is practiced in the developing countries including Kenya. The herbs are used in form of powders, pastes, saps, chewing sticks and seeds. They are sold in Nairobi along streets and open markets with claims of healing all oral diseases. However, safety issues in terms of microbial contaminants, levels of mineral elements profiles, toxicity, phytochemical composition and antimicrobial properties of the herbal materials in the market have not been evaluated. The aim of the study was to evaluate safety aspects and antimicrobial properties of herbal materials used in oral health care in Nairobi. Documentation of herbal materials was carried out by interviewing 60 herbalists using a questionnaire and through informal discussions. Investigation of safety and antimicrobial properties was carried out on 23 herbal products purchased from the herbalists. Evaluation of microbial contaminants was carried out as described by World Health Organisation. Samples were inoculated in enrichment culture medium, then subculturing in selective media, followed by microscopy and biochemical test to confirm the identity of the microbes. Elemental analysis was evaluated by use of Total X-ray Fluorescence Technique. Qualitative phytochemical constituents of herbal materials were investigated using standard methods. The antimicrobial properties were studied using disc and agar well diffusion method. Toxicity effects of herbal materials was investigated by administering 1000 mg/kg body weight of seven herbal material extracts and 3 herbal pastes on mice for twenty one days, and then biochemical, haematological parameters, relative organ weight and their histopathological changes were evaluated. Results indicated that 35 plant species were used in preparation of herbal products for management of oral conditions. Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Candida albicans were isolated in some of the products. High levels of aluminium, phosphorous, potassium, calcium, vanadium, chromium, manganese, iron, nickel, copper, zinc, strontium and lead were observed. Major phytochemical groups were recorded in herbal powders. However, pastes and liquids lacked detectable levels of major phytochemical groups. Antimicrobial properties were reported in 78% of the herbal materials. Mortality was reported in mice treated with herbal materials of Warbugia ugandensis, Zantoxyllum chalybeum and Senna didymobotrya. The extracts of Euclea divinorum and herbal mixtures of Warbugia ugandensis, Z. chalybeum and Terminalia brownii showed retarded growth in mice and hypertrophy of liver and brain. There was significant (P>0.05) alteration of the red blood cells and neutrophils, creatine, alanine aminotransferase and thrombocytes of animals treated with some herbal extracts while severe pathological conditions on vital organs of mice was seen. The toxic effects could be due to presence of heavy metal due to poor handling by herbalists. Most of the products in the market did not meet the WHO standards. These findings may be used to sensitise the Traditional Medical Practitioners, policy makers and consumers on the safety issues and lack of antimicrobial activities in some products. This study recommends that full evaluation of safety and antimicrobial properties of herbal materials be carried out before they are released to the market.