Phenotypic and Molecular Characterization of Pathogenic Bacteria Isolated from Commercialised Herbal Products in Kenya

Background: The widespread use of herbal medicine has led to its approval by World Health Organization (WHO) as a factor in the attainment of universal health care coverage together with conventional medicine. However, unlike conventional medicine, herbal medicine has many challenges yet to be addressed. Pathogenic microbial contamination has been cited as a serious quality issue in previous studies done in Kenya and other countries with no regulation of herbal medicines. Despite newer techniques of microbial analysis taking shape in routine microbial identification and characterization, quality control laboratories use pharmacopoeal techniques to address the same microorganisms without due regard to possible newer contaminants which may not be detected by the traditional routinely used techniques. Objective: This study was designed to use genotypic techniques not utilized before in quality control laboratories for microbial contaminant determination in herbal and nonsterile pharmaceuticals. Materials and Methods: 16SrRNA a unique conserved gene to bacteria was used to identify bacteria that could not be detected by routine methods. Bacterial contaminants were isolated from thirty samples of registered and nonregistered herbal products collected by random purposive sampling from five regions in Kenya. Identification of the unknown isolates was done first by use of selective and differential media as per the British Pharmacopoeia 2007; Biochemical identification was done by API 20E commercial kit according to the manufacturer's instructions. Molecular characterization by DNA fingerprinting, sequencing and phylogenetic analysis was done for the unknown contaminants. Results: Nineteen (19) bacteria were characterized from all the samples. Thirteen isolates were identified by the phenotypic methods while the rest would only be characterized by the molecular methods.