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Beer is a world-famous beverage that is universally popular. This might be as an effect of its sensory, nutritional, and therapeutic qualities. To date, in Côte d'Ivoire, no study has been carried out focused on the eventual health benefits of industrial beer consumption. In this study, the bioactive compounds (total phenols, total tannins, total flavonoids, total anthocyanins) and corresponding antioxidant activities of two industrial beers from maize and rice from two different breweries were investigated. Results showed that for all phenolic compounds, contents were not statistically different (P > 0.05). However, antioxidant activities (antiradical activity and ferric reducing antioxydant power) were more important in industrial beer from rice (57.57 ± 0.62% and 109.46 ± 0.39 µg/mL ascorbic acid irrespectively) than industrial beer from maize (39.19 ± 1.02% and 103.51 ± 0.62 µg/mL ascorbic acid). Total phenols, total flavonoids, and total anthocyanins were mostly responsible for the antioxidant activities (antiradical activity and ferric reducing antioxydant power) of two beers, with correlation coefficients ranging from r = 0.614 to r = 1. Globally, the two industrial beers were similars but differents from local traditional sorghum beer. Occurrence of phenolic compounds in beers coupled with antioxidant activities shows that beer consumption could have health benefits to condition that beers have a low-alcohol content and light-to-moderate consumption. However, further investigations aims health benefis aspect are necessary.

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Studies on yeasts involved in traditional sorghum beer fermentation in several African countries revealed the presence of two groups: Saccharomyces and non-Saccharomyces. If Saccharomyces strains were reputed for their fermentation performances, the non-Saccharomyces yeast strains have been recognized for their contribution towards the improvement of the beverage's organoleptic quality, justifying their use as aromatic starter. In spite of this contribution, most studies were focused only on Saccharomyces strains as starter. In this work, the non-Saccharomyces yeast strains found in the inoculum of traditional sorghum beer was investigated. Identification of non-Saccharomyces yeast strains by PCR-RLFP followed sequencing of D1/D2 domain revealed the presence of 2 species: Issatckenkia orientalis and Pichia kudriavzevii with Issatckenkia orientalis predominating. Out of the two species, fermentation characteristics showed that Issatckenkia orientalis seemed suitable for sorghum beer production.

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In Côte d'Ivoire as elsewhere in Africa, attiéké plays an important role in feeding the population. The objective of the work is to conduct a study on the sanitary quality of the attiéké garba sold in Daloa. Fifty (50) samples of attiéké garba were collected by purchase from various high-traffic outlets in different districts of Daloa town. Samples are collected in the morning around 10 a.m. every 2 days at a rate of 10 per site. Microbiological analyzes and the determination of some physico-chemical parameters of attiéké garba were carried out. The bacterial load of Bacillus cereus present in the samples tested in the majority of districts is greater than or equal to 105 CFU/g of food. About 60% of the samples tested was contaminated with B. cereus spores against 72% contaminated with the vegetative form of B. cereus. However, physicochemical analyzes showed that attiéké garba was acidic and the humidity was between 37.36 ± 15.9 and 55.26 ± 20.5%. Attiéké garba could pose a danger to consumers.

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In recent years, there had been growing demand for distinctive high quality beer. Fermentation management has a fundamental role in beer quality and the levels of aroma compounds. Use of non-conventional yeast has been proposed to enhance beer flavor. In this study, the bioflavor of traditional sorghum beer from Côte d'Ivoire was investigated. The flavor profile of two beers fermented with wild yeasts and with pure culture of Saccharomyces cerevisiae respectively were studied. The main flavor components of the beer fermented by pure culture of Saccharomyces cerevisiae were different from those of the beer fermented with wild yeasts. The total level of esters and higher alcohols were (173.51 and 128.85 mg/L) respectively in the beer fermented with wild yeasts. These levels were significantly higher than those in the beer fermented with pure culture of Saccharomyces cerevisiae which were 13.08 and 78.26 mg/L for higher alcohols and esters respectively. On the other hand, the beer fermented with pure culture of Saccharomyces cerevisiae had an acid content higher than beer fermented with wild yeasts, i.e. 9.3 mg/L and 7.53 mg/L respectively.

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The study describes the transformation of mangoes of the local variety "Assabonou" and papaya solo No.8 into alcohol and then into vinegar through the process of directed fermentation. Indeed, mango and papaya juices extracted from ripe fruits contained in vials are first subjected to an alcoholic fermentation with Saccharomyces cerevisiae in anaerobic conditions and secondly to an acetic fermentation with strains of acetic acid bacteria cultivated from unpasteurized cider vinegar. To assess the quality of the vinegars produced, their profile and composition in organic acid and volatile compounds were compared to those of an unpasteurized cider vinegar from France and a vinegar produced in Côte d'Ivoire. The ethanol content for both juices is more or less high with 9.24 ± 0.04 g/L for mango and 12.68 ± 0.39 g/L for papaya. The concentration of acetic acid is the highest of the organic acids for the four vinegars ranging from 37.46 ± 4.6 g/L to 55.85 ± 9.94 g/L. The acetic acid contents of mango and papaya vinegars are close to that of unpasteurized cider vinegar from France but higher than that of vinegar produced in Côte d'Ivoire. Thus, this study allowed the production of "Assabonou" mango and papaya vinegars from two consecutive fermentations (alcoholic then acetic). This process is fast, less expensive and easily applicable. This application case could be an alternative for the processing of seasonal fruits to reduce postharvest losses.

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Traditional sorghum beer is reputed for its therapeutic virtues in according the consumers. A number of biological active compounds like phenolic compounds (phenol, tannins, flavonoids, anthocyanins), diets fibers and compounds with clinically demonstrated antimalarial activity (quinine formate, quinine dihydrochloride, chloroquine) and antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl and ferric reducing-antioxidant power methods) were evaluated in sorghum wort and beers fermented by wild yeasts and pure culture of Saccharomyces cerevisiae. The total phenol content in the samples ranged between 1254.69 ± 2.31 and 239.68 ± 11.92 µg/mL GAE. Antioxidant activity with 2,2-diphenyl-1-picryl-hydrazyl analysis method was high in sorghum wort with 73.33 ± 1.15% but with ferric reducing-antioxidant power analysis method, the antioxidant activity was high in beer from pure culture of Saccharomyces cerevisiae. No compounds with clinically demonstrated antimalarial activity were found in the samples. At bioactive compounds (phenolic compounds) content point view, statistical analysis showed similarity between the two beers.

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Pseudomonas aeruginosa owns a variability of virulence factors. These factors can increase bacterial pathogenicity and infection severity. Despite the importance of knowledge about them, these factors are not more characterized at level of strains derived from local food products. This study aimed to characterize the virulence potential of P. aeruginosa isolated from various animal products. Several structural and virulence genes of P. aeruginosa including lasB, exoS, algD, plcH, pilB, exoU, and nan1 were detected by polymerase chain reaction (PCR) on 204 strains of P. aeruginosa. They were isolated from bovine meat (122), fresh fish (49), and smoked fish (33). The 16S rRNA gene was detected on 91.1% of the presumptive strains as Pseudomonas. The rpoB gene showed that 99.5% of the strains were P. aeruginosa. The lasB gene (89.2%) was the most frequently detected (p < 0.05). In decreasing importance order, exoS (86.8%), algD (72.1%), plcH (72.1%), pilB (40.2%), and exoU (2.5%) were detected. The lasB gene was detected in all strains of P. aeruginosa serogroups O11 and O16. The prevalence of algD, exoS, and exoU genes in these strains varied from 51.2% to 87.4%. The simultaneous determination of serogroups and virulence factors is of interest for the efficacy of surveillance of infections associated with P. aeruginosa.

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Freeze-drying is a well-known dehydration method widely used to preserve microorganisms. In order to produce freeze-dried yeast starter culture for the brewing purpose of African sorghum beer, we tested protective agents (sucrose, glucose, glycerol) in combination with support materials (millet, maize, sorghum, and cassava flours) at 1:1 ratio (v/v). The yeast strains Saccharomyces cerevisiae F 12-7 and Candida tropicalis C 0-7 previously isolated from sorghum beer were used in a mixed culture at a ratio of 2:1 (C. tropicalis/S. cerevisiae). After the freeze-drying, the residual water contents were between 0.78 -2.27%, 0.55 -4.09%, and 0.40-2.61%, respectively, with sucrose, glucose and glycerol. The dried yeasts viabilities were between 4.0% and 10.6%. Among the protective agents used, sucrose was found to be the best protectant giving cell viabilities of 8.4-10.6%. Considering the support materials, millet flour was the best support after drying. When the freeze-dried yeast powders were stored at 4°C and room temperature (25-28°C) for up to 3 months, the survival rates were the highest with cassava flour as the support material.

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Saccharomyces cerevisiae C8-5 and Candida tropicalis F0-5 isolated from traditional sorghum beer were tested for kinetic parameters on barley malt extract, YPD (863 medium) and for alcohol production. The results showed that C. tropicalis has the highest maximum growth rate and the lowest doubling time. Values were 0.22 and 0.32 h(-1) for maximum growth rate, 3 h 09 min and 2 h 09 min for doubling time respectively on barley malt extract and YPD. On contrary, glucose consumption was the fastest with S. cerevisiae (-0.36 and -0.722 g/l/h respectively on barley malt extract and YPD). When these two yeasts were used as starters in pure culture and co-culture at proportion of 1:1 and 2:1 (cell/cell) for barley malt extract fermentation, we noticed that maltose content increased first from 12.12 g/l to 13.62-16.46 g/l and then decreased. The highest increase was obtained with starter C. tropicalis + S. cerevisiae 2:1. On contrary, glucose content decreased throughout all the fermentation process. For all the starters used, the major part of the ethanol was produced at 16 h of fermentation. Values obtained in the final beers were 11.4, 11.6, 10.4 and 10.9 g/l for fermentation conducted with S. cerevisiae, C. tropicalis, C. tropicalis + S. cerevisiae 1:1 and C. tropicalis + S. cerevisiae 2:1. Cell viability measurement during the fermentation by using flow cytometry revealed that the lowest mean channel fluorescence for FL3 (yeast rate of death) was obtained with C. tropicalis + S. cerevisiae 2:1 after 48 h of fermentation.

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The aim of this study was to evaluate the prevalence of Clostridium difficile and Clostridium perfringens in cooked beef sold in the streets in Côte d'Ivoire and their antimicrobial susceptibility. A total of 395 kidney and flesh samples of cooked beef were collected from vendors at Abidjan and subjected to C. difficile and C. perfringens isolation and identification by using biochemical tests, API 20A system and PCR detection. Subsequently, the antimicrobial susceptibility test was performed for confirmed isolates. Our results showed the prevalence of 12.4% for C. difficile (11.04% in kidney and 13.45% in flesh) and 5.06% for C. perfringens (2.32% in kidney and 7.17% in flesh). Metronidazole and vancomycin remained the most potent antimicrobial agents against C. difficile while metronidazole and penicillin G were the most potent agents against C. perfringens. The resistance rates to tetracycline, doxycycline, chloramphenicol and erythromycin against C. difficile and C. perfringens isolates ranged from 2.05% to 8.16% and from 20% to 50%, respectively. Among all antimicrobial agents tested against C. difficile, percentages of resistance to quinolones ciprofloxacin, norfloxacin and nalidixic acid as well as to gentamicin and cefotaxime were the highest. Eight resistant phenotypes were defined for C. difficile isolates and eleven resistant phenotypes for C. perfringens isolates. Clindamycin/gentamicin/cefotaxime/ciprofloxacin/norfloxacin/nalidixic acid resistance was the most common phenotype for C. difficile (55.10% of isolates) while norfloxacin/nalidixic acid resistance was the most common phenotype for C. perfringens (20% of isolates).

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This study investigated the diversity and dynamics of yeasts involved in alcoholic fermentation of a traditional sorghum beer from Côte d'Ivoire, tchapalo. A total of 240 yeast strains were isolated from fermenting sorghum wort inoculated with dry yeast from two geographic regions of Côte d'Ivoire (Abidjan and Bondoukou). Initial molecular identification to the species level was carried out using RFLP of PCR-amplified internal transcribed spacers of rDNA (ITS1-5.8S-ITS2). Ten different profiles were obtained from the restriction of PCR products with the three endonucleases HaeIII, CfoI and HinfI. Sequence analysis of the D1/D2 domain of the 26S rDNA and the ACT1 gene allowed us to assign these groups to six different species: Saccharomyces cerevisiae-like, Candida tropicalis, Pichia kudriavzevii, Pichia kluyveri, Kodamaea ohmeri and Meyerozyma caribbica. The most frequent species associated with tchapalo fermentation was S. cerevisiae-like (87.36%), followed by C. tropicalis (5.45%) and M. caribbica (2.71%). S. cerevisiae-like strains were diploid heterozygotes and exhibited three to four nucleotides divergence from the type strain in the D1/D2 domain and several indels in the more discriminant sequence of the intron of the ACT1 gene. During the process, the yeast species isolated and their frequencies varied according to the geographic origin of the dry yeast. The occurrence of some species was sporadic and only two non-Saccharomyces species were found in the final product.

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