Risk of Fungi Associated with Aflatoxin and Fumonisin in Medicinal Herbal Products in the Kenyan Market

Utilization of herbal products is a major concern due to the possibility of contamination by toxigenic fungi that are mycotoxin producers such as Aspergillus species during processing and packaging. Research was carried out to determine the presence of aflatoxins and fumonisins in herbal medicinal products sold in Eldoret and Mombasa towns in Kenya. The study employed both exploratory and laboratory experimental design. The herbal products were purchased from the market and transported to Kenya Medical Research Institute for processing and analysis. Fungal contaminants were determined according to Pharmacopoeia specifications. The toxins were quantified using ELISA based technique. The genus Aspergillus was the most dominant followed by Penicillium. Fungal counts ranged between 1 CFU/g and >1000 cfu/g. Analysis of variance showed that the rate of fungal contaminants for Eldoret and Mombasa samples had significant association (p≤0.001). Aflatoxin levels ranged from 1 to 24 ppb, while fumonisin levels ranged from 1 to >20 ppb. Only 31% of samples met the standards for microbial limits as specified in Pharmacopoeia. There is need for product microbial quality improvement through proper harvesting, processing, storage, and marketing. It is recommended that a policy be enacted to enable regulation of herbal products in Kenya

Validation of Safety and Efficacy of Antitussive Herbal Formulations

Background: Cough is an important defensive pulmonary reflex that removes irritants, fluids or foreign materials from the airways. Frequently, cough is non-productive and requires suppression and opioid receptor agonists such as codeine are commonly used as antitussive agents. However, opioids produce side effects that include sedation, addiction potential and constipation. Novel cough suppressant therapies should maintain or improve upon the antitussive efficacy profile of opioids but with minimum or no side effects. Objective: To evaluate antitussive activity of combination of herbal medicines as formulations in sulphur dioxide - induced cough model in rats. Methodology: Wister rats of either sex, weighing 150 - 200 g, were divided into 7 groups (n = 6). Group 1 served as a control and received normal saline, groups 2 received codeine phosphate, group 3 and 4 received the coded market samples and groups 5, 6 and 7 received the test samples, respectively. Thirty or sixty minutes following administration, the rats were exposed to sulphur dioxide gas for 1 minute and then placed in an open chamber for counting of cough bouts. Results: The formulations exhibited cough inhibitions of between 15 and 27%, and 14 and 38%, with respect to the control group, 30 and 60 minutes after sample administration respectively. Conclusion: The herbal formulations demonstrated significant (p < 0.05) antitussive activity in sulphur dioxide induced cough model. Key words: Antitussive activity; herbal formulations; sulphur dioxide; coug

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Antimicrobial properties and toxicity of Hagenia abyssinica (Bruce) J.F.Gmel, Fuerstia africana T.C.E. Fries, Asparagus racemosus (Willd.) and Ekebergia capensis Sparrm.

Background: The world health organization (WHO) estimates that 80% of population in Africa relies on traditional remedies for their healthcare. However, very few studies have been carried out to establish the therapeutic effects of these remedies. Objective: Four medicinal plants were investigated for antimicrobial activity and toxicity. Materials and Methods: Plants were collected from their natural habitat, dried, and extracted with organic and aqueous solvents. Antimicrobial activity was determined by the disc diffusion assay technique. In vitro cytotoxicity studies were carried out on extracts using MTT assay on Vero cell lines while acute toxicity in Swiss mice. Results: Extracts from H. abyssinica, F. africana and A. racemosus exhibited antibacterial activity with minimum inhibitory concentration of ≤ 6.25mg/ml against S. aureus, MRSA and P. aeruginosa. However, the plants studied had weak antifungal activity. H. abyssinica and F. africana extracts were found to be cytotoxic with CC50 of ˂ 90 µg/ml. These extracts were tested for acute toxicity and found to be safe at 5000 mg/kg body weight per day. Conclusion: The results of the study support the medicinal use of these plants and indicate that useful compounds from Hagenia abyssinica and Fuerstia africana can be isolated for further exploitation. Keywords: Medicinal plants, Antimicrobial activity, Cytotoxicity, Acute toxicit

In vitro Cytotoxic Activities of Catha edulis (Vahl) Forssk. Ex Endl. (Khat) Varieties from Kenya on Select Cancer Cell Lines

Khat (Catha edulis (Vahl) Forssk.) is a herb from the Celastraceae family (also known as qat, gaad, or miraa). The leaves and stems are used medicinally and for recreational purposes. The communities that grow khat have identified different varieties based on perceived appearance and quality. This study aimed to evaluate the cytotoxicity of khat varieties grown in the Meru and Embu Counties of Kenya. Field studies were undertaken in the markets and farms in Meru and Embu Counties of Kenya to document and purchase local khat varieties. Dried khat was extracted with a 1:1 v/v MeOH: CH2Cl2 solvent and water. Cytotoxicity of extracts was determined in vitro by MTT assay against four normal and cancer cells namely; HeLa ATCC® CCL-2™, HCC1395 ATCC® CRL-2324™, Hep2 ATCC® CCL-23™, and Vero E6 ATCC® CRL-1586™. The khat varieties identified were Muti Mutiiri, Mugwanthingi, Gicheru, Karimi ka Nthiya, Muguka, Black colombo asili, Black mbaine, and white. The aqueous extracts of black colombo asili and black mbaine displayed the highest cytotoxic activity against HeLa cell lines having IC50 37.15 ± 1.75 µg/ml and 38.31 ± 2.05 µg/ml, respectively. Muguka and Muti Mutiiri varieties were not cytotoxic to the Vero E6 cell line with CC50 &gt; 100 µg/ml. 75% (12/16) of extracts were cytotoxic to the Vero E6 cell line with CC50 ˂ 100 µg/ml. This study demonstrated that there is variability in activities between the identified khat varieties. Toxicity was observed in vitro due to observed cytotoxicity to the Vero E6 cell line.</jats:p