Aim: The aim of this study was to evaluate the sanitary quality of smoked fish by determining their mycotoxin content, and also the chemical composition, antifungal activity of Cymbopogon citratus and Ocimum basilicum essential oils from Cameroon against some mycotoxigenic fungal strains responsible of the smoked fish biodegradation. Place and Duration of Study: Laboratory of Food Microbiology and Biotechnology, National School of Agro-Industrial Sciences, University of Ngaoundere, Cameroon, from August 2019 to April 2020. Methodology: Fifteen samples of smoked fishes have been collected in August 2019 from “petit marché” market (Ngaoundere, Cameroon). Physico-chemical parameters of smoked fishes were evaluated. Mycotoxin (AFB1, CIT, and OTA) contents have been determined with HPLC. Isolation and identification of molds were done using their macroscopic and microscopic characteristics, and the identity of the strains was done by PCR sequencing methods. For plants, 15 kg of Cymbopogon citratus leaves and 5 kg of Ocimum basilicum leaves have been harvested on 10 September 2019 in Ngaoundere and used for the essential oil’s extraction. Essential oil extraction has been done through hydrodistillation and the determination of its chemical composition done with GC/MS. Results: Major part of samples contains at least one mycotoxin, in quantities which are beyond the safe dose. Eleven species of molds have been identified: Aspergillus spp., Penicillium citrinum, and Mucor hiemalis. Amongst the isolated species, those which can produce mycotoxins are: Penicillium citrinum, Aspergillus versicolor, Aspergillus fumigatus, Aspergillus carbonarius, Aspergillus niger, and Fusarium moniliforme. Geranial (42.4%), Neral (33.5%) and Myrcene (10.8%) are major compounds found in the essential oil of C. citratus while monoterpens (60.8%), Eugenol (30.7%), Linalol (29.4%) and 1,8-Cineol (14.3%) are the major compounds found in the essential oil of O. basilicum.  Conclusion: Essential oils of C. citratus and O. basilicum are efficient against isolated toxigenic species. C. citratus being more efficient than O. basilicum.

With a view to finding alternative compounds to the synthetic chemicals used in food preservation, a study was initiated to evaluate the antifungal activity of C. citratus essential oil on toxigenic molds isolated from Cameroonian rice. To this end, 12 rice samples of one kilogram each was taken in October 2019 in four cities in Cameroon: Tonga, Ndop, Yagua and Maga. Water activity in the rice samples collected was measured using an electronic hygrometer; mycotoxins were determined by HPLC. The isolation and identification of fungal strains were done on the basis of macroscopic and microscopic characteristics, and the identity of the strains was confirmed by PCR-sequencing. The extraction of the essential oil was done using a Clevenger by hydrodistillation, and the analysis of its chemical composition by GC/MS. From these analyses, it appears that all samples tested are contaminated with at least one mycotoxin, and that the three mycotoxins tested (AFB1, CIT and OTA) are indeed present in our rice samples, but at values not exceeding the limits set by European Commission Regulation N0 1881/2006. Seven cases of co-contamination have been identified. On the other hand, 9 fungal genera have been identified and the dominant genera being Aspergillus, Penicillium and Fusarium, all of which are involved in the synthesis and excretion of mycotoxins in cereals. The essential oil of C. citratus has been shown to be effective in inhibiting the growth of A. carbonarius, A. versicolor, F. graminaerum, F. moniliform and P. citrinum; and the main compounds of this oil are geranial (42.4%), neral (33.5%) and myrcene (10.8). A. carbonarius was the most sensitive strain to the essential oil, and F. moniliform was the most resistant strain.

The aimed of this study to evaluate the antifungal activity of essential oils of Ocimum basilicum L. on some fungi isolated from commercial rice sold in Cameroon. Fungal isolates were primarily identified based on morphological characteristics, while representative isolates were identified using PCR-based methods. Essential oils were extracted by hydro-distillation, chemical composition was analyzed by gas chromatography coupled with mass spectrometry (GC-MS) and antifungal activity against isolated fungi were assessed using the micro-atmospheric method. The percentage of frequency and abundance varied with the sample analyzed and the fungi detected. A total of 85 fungal isolates of eight genera including Aspergillus, Fusarium, Penicillium, Rhizopus, Cladosporum, Mucor Alternaria and Acremonium in decreasing order of predominance were identified. The most fungal species identified were Aspergillus flavus, A. fumgatis, A. niger, A. carbonarius, Fusarium oxysporum, F. graminarum, F. moniliforme, Penicillium citrinum, P. expansum, Rhizopus oryzea, Cladosporum sp, Mucor hiemalis, Alternaria solani, Acremonium murorum. More than 61% (A. flavus, A. niger, P. citrinum) and 44% (M. hiemalis, A. flavus, A. niger) of analyzed samples contain respectively aflatoxin B1, AFB1 (0 - 17.3 µg/kg) and ochratoxin A, OTA (0 - 5.2 µg/kg). Citrinin was not detected. The main compounds identified in O. basilicum EO are eugenol (30.6), linalool (29.5), cineole (14.4), Terpinen-4-ol (5.6), 2-norpinen (4.1), Cadinen (3.3), Limonen (2.4) and (E)-β-Ocimene (2.2). The O. basilicum EO exhibit antifungal activity with the MIC range from 750-2000 ppm. This activity varies with the strains and the concentration of EO. The increased prevalence of mycotoxigenic fungi in rice, a highly consumed food grain in Africa, poses serious health concerns to the general public. The O. basilicum EO can therefore be used as alternatives to synthetic pesticide in rice storage.

Background: Limited access to safe drinking water and lack of information on water quality in the sub-urban and rural regions of Cameroon has contributed to regular outbreaks of diarrheal diseases. Objectives: The aim of this study was to assess the bacteriological quality of drinking water in the Vina division. Methods: A total of 193 water samples were collected from unprotected boreholes, unprotected wells and unprotected clay pots and analyzed physico-chemically including pH, turbidity, total dissolved solid, conductivity and microbiologically such as enumeration of Enterococcus sp., Escherichia coli, Salmonella sp. and Vibrio sp using standard methods. This study revealed that safe status of the groundwater sources in the Vina division is very poor, considering the high levels of E.coli, Enterococcus sp. and the presence of enter pathogens microorganism such as Vibrio sp., Salmonella sp. and Shigella sp. Representative isolates (26) based on biochemical profile were selected for antibio resistance profile. All selected bacteria exhibited multiple antibiotic resistance at least for five antibiotics including ampicillin, amoxicillin + Clavulanic acid, amoxicillin, penicillin, erythromycin. Conclusion: This study suggests that drinking water available in Vina division of Cameroon lead to a substantial risk to public health. It is therefore necessary to developed strategies for protection of areas around drinking water supplies site. Further studies are therefore needed to assess the prevalence of water borne diseases in Vina division.

Water related disease is defined as any significant or widespread adverse effects on human health, such as death, disability, illness or disorders, caused directly or indirectly by the condition, or changes in the quantity or quality of any water. This crossectional and analytical study, carried out from July to December 2019 at the Ngaoundere Regional Hospital and Protestant Hospital aimed to determine the prevalence of water related diseases in the Vina Division. Retrospective data of patients records covered the period of five years (2014 to 2018) were analyzed in order to identify common water related diseases in the study area. Document review technique was adopted in this study; outpatients/inpatients registers were reviewed and information on socio-demographic characteristics of each individual patient were collected. Also, the bacteriological characterization of stool samples collected from patients was done to identify the most frequent bacteria responsible for water related disease in the area, followed by an antibacterial susceptibility testing of some isolated bacteria using standard methods. Results show that, out of 153073 patients recorded from 2014 to 2019, 63750 were clinically diagnosed for water related diseases, giving a prevalence of 41%.  Overall, typhoid fever and malaria were the most prevailing water related diseases confirmed clinically with a prevalence of 43%. Parasitic infections were the least prevailing (3.7%). The study revealed that, females was more prone to water related cases than males. Bacteria were more sensitive to streptomycin and resistant to amoxicillin. This study shows that water related diseases are a major health problem in the Vina Division. Routinely monitoring of drinking water sources is recommended to the different users in order to limit the spread of water related diseases.