Technology and physico-chemical characteristics of Bikalga, alkaline fermented seeds of Hibiscus sabdariffa

Bikalga is a product of traditional alkaline fermentation of Hibiscus sabdariffa used as food condiment in African countries including Burkina Faso. Its production process was studied at different productionsites of Burkina Faso where the different steps of the technology were recorded, specific diagram of production of each production site was established and a general flow diagram proposed. The changesin pH throughout the fermentation was measured and the proximate composition of unfermented and fermented seeds was determined. The presence of minerals in both unfermented and fermented seedswas also determined by spectrophotometry. The production of Bikalga involves many steps with the most important being cleaning, cooking (with addition of alkalinizing ash leachate), fermentations, steaming and drying. During the process, pH increased with cooking and fermentation (pH 8 - 9), then decreased mainly with steaming and drying (pH 6 in some cases). The studied raw seeds were composed of 28.69 ± 1.15% of crude proteins, 21.93 ± 0.74% of crude lipids, 26.39 ± 1.03 % ofcarbohydrates and the fermented seed showed 26.47 ± 1.5 for proteins 23.19 ± 1.25 for crude lipids and 13.7 ± 0.62 for carbohydrates. An increase of moisture and ash content as well as total titratable and fatacidity occurred with the fermentation. Variable minerals were detected in the seeds with an outstanding increase (in some cases) of potassium and a pronounced increase of sulphur, sodium and calcium in the final product

Investigation of the diversity and safety of the predominant Bacillus pumilus sensu lato and other Bacillus species involved in the alkaline fermentation of cassava leaves for the production of Ntoba Mbodi

The objective of the study was to investigate the identity, diversity, and safety of the Bacillus population involved in the fermentation of cassava (Manihot esculenta Crantz) leaves for the production of Ntoba Mbodi, a Congolese food. Ninety bacteria were identified by phenotyping and genotyping using ITS-PCR, rep-PCR, and sequencing of the 16S rRNA, gyrA, gyrB and rpoB genes. Moreover, the isolates were screened for the presence of genes coding for haemolytic (HblC, HblD) and non-haemolytic enterotoxins (NheA, NheB and NheC), cytotoxin K (CytK) and emetic toxin (EM1) as well as their ability to produce haemolysin. The investigations revealed the predominance (72.21 %) of species of the Bacillus pumilus group i.e. B. safensis (48), B. pumilus (7), and B. pumilus sensu lato (10). Other species of Bacillus including B. cereus sensu lato (11), B. megaterium (4), B. subtilis (4), B. amyloliquefaciens (2), B. siamensis (2), B. licheniformis (1) and Lysinibacillus louembei were also identified. Haemolytic, non-haemolytic and cytokin toxin genes were detected in the B. cereus strains which were also able to produce haemolysin. The emetic toxin gene was not detected in any isolates. The toxin genes screened were not detected in any of the non B. cereus species

Antimicrobial Resistance of Lactic Acid Bacteria from Nono, a Naturally Fermented Milk Product

Background: Antimicrobial resistance (AMR) is one of the biggest threats to public health. The food chain has been recognised as a vehicle for transmitting AMR bacteria. However, information about resistant strains isolated from African traditional fermented foods remains limited. Nono is a traditional, naturally fermented milk product consumed by many pastoral communities across West Africa. The main aim of this study was to investigate and determine the AMR patterns of lactic acid bacteria (LAB) involved in the traditional fermentation of milk for Nono production, and the presence of transferable AMR determinants. Methods: One hundred (100) LAB isolates from Nono identified in a previous study as Limosilactobacillus fermentum, Lactobacillus delbrueckii, Streptococcus thermophilus, Streptococcus infantarius, Lentilactobacillus senioris, Leuconostoc pseudomesenteriodes, and Enterococcus thailandicus were investigated. The minimum inhibitory concentration (MIC) was determined for 18 antimicrobials using the micro-broth dilution method. In addition, LAB isolates were screened for 28 antimicrobial resistance genes using PCR. The ability of LAB isolates to transfer tetracycline and streptomycin resistance genes to Enterococcus faecalis was also investigated. Results: The experiments revealed variable antimicrobial susceptibility according to the LAB isolate and the antimicrobial tested. The tetracycline resistance genes tet(S) and tet(M) were detected in isolates Ent. thailandicus 52 and S. infantarius 10. Additionally, aad(E) encoding resistance to streptomycin was detected in Ent. thailandicus 52. The conjugation experiments suggested that the tet(S) and aad(E) genes were transferable in vitro from isolate Ent. thailandicus 52 to Ent. faecalis JH2-2. Significance and Impact: Traditional fermented foods play a significant role in the diet of millions of people in Africa, yet their contribution to the burden of AMR is largely unknown. This study highlights that LAB involved in traditionally fermented foods could be potential reservoirs of AMR. It also underscores the relevant safety issues of Ent. thailandicus 52 and S. infantarius 10 for use as starter cultures as they carry transferable AMR genes. Starter cultures are an essential aspect of improving the safety and quality attributes of African fermented foods. However, AMR monitoring is an important safety aspect in the selection of starter cultures for improving traditional fermentation technologies

Faecal carriage of extended-spectrum beta-lactamase-producing Enterobacteriaceae in healthy volunteers and hospitalized patients in Ouagadougou, Burkina Faso: prevalence, resistance profile, and associated risk factors

Background: Extended spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) are a serious challenge to patients’ treatment. The aim of this study is to determine the prevalence of ESBL-PE, investigate the associated resistance, and analyze the associated risk factors for acquisition of ESBL-PE.Methodology: A cross-sectional study was conducted on healthy volunteers and inpatients. After obtaining informed consent, rectal swabs were collected from each participant for isolation of Enterobacteriaceae on Hektoen enteric agar containing 4µg/L cefotaxime. The Enterobacteriaceae isolates were identified using biochemical tests and ESBL production was confirmed by the double-disc synergy test of amoxicillin and clavulanic acid. Antibiotic susceptibility test of each isolate was done by the disc diffusion method and interpreted using the recommendations of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) clinical  breakpoints version 5.0.Results: During the study period, prevalence of faecal ESBL-PE among the study participants was 54.5% (103/189); 53.5% among healthy volunteers and 55.7% among inpatients (p=0.87). The major ESBL-PE isolates was Escherichia coli (71%) followed by Klebsiella pneumoniae (16%). The isolates in hospitalized patients were resistant to norfloxacin (84.2%), cotrimoxazole (89.5%), and gentamicin (7.0%). The isolates from healthy volunteers were resistant to norfloxacin (86.2%), cotrimoxazole (82.8%), and gentamicin (1.7%).Gender, age, and previous antibiotic use were not significantly associated with carriage of ESBL-PE (p=0.51).Conclusion: The high prevalence of ESBL-PE in this study is worrying. There is an urgent need to develop measures to monitor and limit the spread of these multidrug-resistant organisms in healthcare facilities and the community in Burkina Faso. Keywords: faecal carriage, ESBL-PE, healthy volunteers, inpatients, Burkina Fas

Identification and characterisation of the lactic acid bacteria associated with the traditional fermentation of dairy fermented product

The aim of this research was to identify the key lactic acid bacteria associated with the fermentation of dairy traditional fermented products for developing starter cultures for controlled fermentation. A total of 100 lactic acid bacteria (LAB) were isolated from dairy traditional fermented products. Samples were obtained from eight producers in the South East of Nigeria. Isolates were identified by phenotypic and genotypic techniques including rep-PCR genotyping and sequencing of the 16S rRNA, pheS and rpoA genes. Isolates were characterised for antimicrobial activity against foodborne pathogens, exopolysaccharide (EPS) production and survival at low pH and in the presence of bile salts. All isolates clustered into 11 distinct rep-PCR groups and were identified as Lactobacillus fermentum (40%), Lactobacillus delbrueckii (23%), Streptococcus thermophilus (22%), Streptococcus infantarius (10%), Lactobacillus senioris (2%), Leuconostoc pseudomesenteriodes (2%) and Enterococcus thailandicus (1%). Lactobacillus fermentum showed a broad spectrum antimicrobial activity and survival at low pH, while Lactobacillus delbrueckii was able to tolerate low pH and produce EPS. All isolates survived in vitro exposure to 1% (w/v) bile salts over a 3-h period. L. fermentum, L. delbrueckii and S. thermophilus could be used to simulate the fermentation of dairy traditional fermented products

Is diet partly responsible for differences in COVID-19 death rates between and within countries?

Correction: Volume: 10 Issue: 1 Article Number: 44 DOI: 10.1186/s13601-020-00351-w Published: OCT 26 2020Reported COVID-19 deaths in Germany are relatively low as compared to many European countries. Among the several explanations proposed, an early and large testing of the population was put forward. Most current debates on COVID-19 focus on the differences among countries, but little attention has been given to regional differences and diet. The low-death rate European countries (e.g. Austria, Baltic States, Czech Republic, Finland, Norway, Poland, Slovakia) have used different quarantine and/or confinement times and methods and none have performed as many early tests as Germany. Among other factors that may be significant are the dietary habits. It seems that some foods largely used in these countries may reduce angiotensin-converting enzyme activity or are anti-oxidants. Among the many possible areas of research, it might be important to understand diet and angiotensin-converting enzyme-2 (ACE2) levels in populations with different COVID-19 death rates since dietary interventions may be of great benefit.Peer reviewe

Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity

Techniques d'amélioration de la production agricole en zone soudano-sahélienne : manuel à l'usage des techniciens du développement rural, élaboré au Yatenga, Burkina Faso

L'amélioration de la production agricole en Afrique soudano-sahélienne , et plus particulièrement au Yatenga (Burkina Faso), implique d'une part de développer les capacités d'organisation des producteurs, et d'autres part de vulgariser des innovations techniques permettant de résoudre en partie les principaux problèmes que rencontrent les paysans. Ce manuel rassemble 31 fiches techniques qui concernent la plupart des domaines d'intérêt des paysans du Yatenga : la défense et la restauration des sols, l'amélioration des productions végétales et animales, l'utilisation des résidus de récolte et le machinisme agricole. Il s'adresse tout particulièrement aux techniciens de développement rural et à toute personne qui s'intéresse à l'agriculture, au Yatenga et dans des régions soudano-sahéliennes aux caractéristiques similaire