Nigerian foods of probiotics relevance and chronic metal exposure: a systematic review

The Involvement of Lactic Acid Bacteria and Their Exopolysaccharides in the Biosorption and Detoxication of Heavy Metals in the Gut

Heavy metal pollution has become one of the most important global environmental issues. The human health risk posed by heavy metals encountered through the food chain and occupational and environmental exposure is increasing, resulting in a series of serious diseases. Ingested heavy metals might disturb the function of the gut barrier and cause toxicity to organs or tissues in other sites of the body. Probiotics, including some lactic acid bacteria (LAB), can be used as an alternative strategy to detoxify heavy metals in the host body due to their safety and effectiveness. Exopolysaccharides (EPS) produced by LAB possess varied chemical structures and functional properties and take part in the adsorption of heavy metals via keeping the producing cells vigorous. The main objective of this paper was to summarize the roles of LAB and their EPS in the adsorption and detoxification of heavy metals in the gut. Accumulated evidence has demonstrated that microbial EPS play a pivotal role in heavy metal biosorption. Specifically, EPS-producing LAB have been reported to show superior absorption, tolerance, and efficient abatement of the toxicity of heavy metals in vitro and/or in vivo to non-EPS-producing species. The mechanisms underlying EPS-metal binding are mainly related to the negatively charged acidic groups and unique steric structure on the surface of EPS. However, whether the enriched heavy metals on the bacterial cell surface increase toxicity to local mammal cells or tissues in the intestine and whether they are released during excretion remain to be elucidated.

Immune System and Epidemics: The Role of African Indigenous Bioactive Substances

With over 6 million coronavirus pandemic deaths, the African continent reported the lowest death rate despite having a high disease burden. The African community's resilience to the pandemic has been attributed to climate and weather conditions, herd immunity, repeated exposure to infectious organisms that help stimulate the immune system, and a disproportionately large youth population. In addition, functional foods, herbal remedies, and dietary supplements contain micronutrients and bioactive compounds that can help boost the immune system. This review identified significant traditional fermented foods and herbal remedies available within the African continent with the potential to boost the immune system in epidemics and pandemics. Methodology: Databases, such as PubMed, the Web of Science, and Scopus, were searched using relevant search terms to identify traditional African fermented foods and medicinal plants with immune-boosting or antiviral capabilities. Cereal-based fermented foods, meat-, and fish-based fermented foods, and dairy-based fermented foods containing antioxidants, immunomodulatory effects, probiotics, vitamins, and peptides were identified and discussed. In addition, nine herbal remedies and spices belonging to eight plant families have antioxidant, immunomodulatory, anti-inflammatory, neuroprotective, hepatoprotective, cardioprotective, and antiviral properties. Peptides, flavonoids, alkaloids, sterols, ascorbic acid, minerals, vitamins, and saponins are some of the bioactive compounds in the remedies. Bioactive compounds in food and plants significantly support the immune system and help increase resistance against infectious diseases. The variety of food and medicinal plants found on the African continent could play an essential role in providing community resilience against infectious diseases during epidemics and pandemics. The African continent should investigate nutritional, herbal, and environmental factors that support healthy living and longevity.

Two sides of the same coin: Meta-analysis uncovered the potential benefits and risks of traditional fermented foods at a large geographical scale

Traditional fermented foods, which are well-known microbial resources, are also bright national cultural inheritances. Recently, traditional fermented foods have received great attention due to their potential probiotic properties. Based on shotgun metagenomic sequencing data, we analyzed the microbial diversity, taxonomic composition, metabolic pathways, and the potential benefits and risks of fermented foods through a meta-analysis including 179 selected samples, as well as our own sequencing data collected from Hainan Province, China. As expected, raw materials, regions (differentiated by climatic zones), and substrates were the main driving forces for the microbial diversity and taxonomic composition of traditional fermented foods. Interestingly, a higher content of beneficial bacteria but a low biomass of opportunistic pathogens and antibiotic resistance genes were observed in the fermented dairy products, indicating that fermented dairy products are the most beneficial and reliable fermented foods. In contrast, despite the high microbial diversity found in the fermented soy products, their consumption risk was still high due to the enrichment of opportunistic pathogens and transferable antibiotic resistance genes. Overall, we provided the most comprehensive assessment of the microbiome of fermented food to date and generated a new view of its potential benefits and risks related to human health.

Foods of the Mediterranean diet: lacto-fermented food, the food pyramid and food combinations

The Mediterranean diet proved to be one of the healthiest diets in the word. It has several beneficial effects and it prevents many non-communicable diseases, such as cancer, cardiovascular diseases, and obesity. Before being a culinary regime, the Mediterranean diet is characterized by specific cultural heritages and traditions, also influencing the lifestyle of the populations. The Mediterranean diet follows the so-called food pyramid, comprising several food combinations. Indeed, it is mainly composed by vegetables, fish and dairy products, while red meat and sweets are poorly consumed. Processed foods are mainly avoided, apart from lacto-fermented ones, the first processed foods consumed by humans. Food fermentation by microorganisms not only improves the functionality of bioactive metabolites, but also increases the shelf life and organoleptic properties of the food. Lactic acid bacteria play a vital role in transforming the food constituents, thereby enhancing their nutritional and functional properties. In addition, these foods introduce beneficial bacteria into gut microbiota, thus maintaining a healthy gut microbiome and corresponding gut-brain axis, thus providing an overall improvement in health and a reduced risk of non-communicable diseases and metabolic disorders. This review will focus on the Mediterranean diet, on its characterising food pyramid and food combinations, and on lacto-fermented foods, one of the components of the Mediterranean diet with the most beneficial effects.

Eating Fermented: Health Benefits of LAB-Fermented Foods

Lactic acid bacteria (LAB) are involved in producing a considerable number of fermented products consumed worldwide. Many of those LAB fermented foods are recognized as beneficial for human health due to probiotic LAB or their metabolites produced during food fermentation or after food digestion. In this review, we aim to gather and discuss available information on the health-related effects of LAB-fermented foods. In particular, we focused on the most widely consumed LAB-fermented foods such as yoghurt, kefir, cheese, and plant-based products such as sauerkrauts and kimchi.

Toxic Metals and Non-Communicable Diseases in HIV Population: A Systematic Review

Background and Objectives: HIV has been a serious global health concern since its discovery, with about 37.9 million people living with HIV worldwide as of 2018. Sub-Saharan Africa (SSA) accounts for 68% of the infection and contributed 74% of the 1.5 million deaths in 2013 despite having only 12% of the total world population residing in the region. This systematic review has attempted to determine the association between heavy metal toxicity and the occurrence of non-communicable diseases in the HIV/AIDS population. Materials and Methods: Three databases were systematically searched: PubMed, Scopus, and Google Scholar for studies written in English and published between 1 April 2000 and 12 April 2020. Studies were excluded if the main outcomes were not measured or did not meet the inclusion criteria. Results: All the six included studies are cross-sectional in design, and therefore were evaluated using the STROBE checklist. The data extraction was done using an extraction table; the ratio of female to male participants included in the study was 1.09:1. Qualitative analysis was used due to the heterogeneity in the heavy metal biomarkers and the outcome measured by the included studies. Two studies compared the concentration of heavy metals in HIV-positive and HIV-negative participants while one compared the levels between HAART-naïve and HAART-treated participants, and three determined the association between heavy metal toxicity and non-communicable diseases (liver fibrosis, anaemia, and reproductive parameters, respectively) in HIV-positive patients. Conclusions: Blood lead, cadmium, and mercury levels were higher in HIV-seropositive than -seronegative subjects, whereas serum zinc level was lower in HIV-seropositive than -seronegative subjects, but the causal association between heavy metals and non-communicable diseases in HIV subjects is largely unknown. Interdisciplinary research between nutrition, toxicology, and human health is envisaged for primary and secondary prevention and treatment.

Descriptive Analysis of Heavy Metals Content of Beef From Eastern Uganda and Their Safety for Public Consumption

In this study, we initiated an effort to generate information about beef safety in Uganda. Our entry point was to assess by atomic absorption spectrophotometry the levels of essential elements copper (Cu), cobalt (Co), iron (Fe) and zinc (Zn), and non-essential elements lead (Pb), chromium (Cr), nickel (Ni), and cadmium (Cd) in 40 beef samples collected from within and around Soroti (Uganda). The information was used to evaluate the safety of consuming such beef against the World Health Organization (WHO) limits. The latter was accomplished by (i) estimating the daily intake (EDI) of each metal in the study area, (ii) modeling the non-cancer health risk using the target hazard quotient (THQ) and (iii) modeling the cancer risk using the incremental lifetime cancer risk (ILCR). The study finds that the mean concentrations (±95% CI) and EDI were in the order of Fe > Zn > Cr > Ni > Pb > Co > Cu > Cd. Cancer risk was found to be due to Ni > Cr > Cd > Pb and significantly higher in children than adults. The latter particularly demonstrates the importance of Ni poisoning in the study area. Overall, while essential elements in our beef samples were below WHO limits (hence no health risks), non-essential elements had high health and cancer risks due to higher levels of Cr and Ni.

Toxicological Risk Analysis in Data-Poor Countries: A Narrative Approach to Feed an "Awareness Raising-Community Empowerment" Vortex

Background and objectives: With globalization of culture and products, choices and behaviors associated with the unawareness of toxicological risk factors result in human and environmental toxic exposures along with health disparities. Toxic exposures are risk factors for malnutrition and diseases, impairing the chances of being healthy and having a healthy adulthood for current and next generation(s). Increasing research funds, infrastructures, analytical data and risk assessment is a reality well worth attention in sub-Saharan Africa. These countries are still unprotected nowadays and are particularly exposed and data-poor in respect to risk factors (e.g., neurotoxicants, immunotoxicants and endocrine disruptors). This paper presents how-based on scientific literature-low-resource countries may achieve more with less. As one of the world's most important emerging markets, Africa can, and should, assess the benefits and risks of modernity versus tradition and ask for safe and quality products at affordable prices while producing safe and nutritious foods. Materials and Methods: Exempla and experiences of risk analysis based on participant observation in field anthropological research, consumer safaris and reportages in the field of food safety, environmental health and consumer products are discussed in terms of "narrative prevention" and its power to highlight previously unrecognized/overlooked real-life risk scenarios. Knowledge return initiatives are discussed in light of their power to feed awareness raising, informed choice and empowerment of communities. Results: In some cases, data exist but remain too sparse, unknown or underused; in other cases, the information is totally neglected. When there is international scientific evidence, a diagnostic risk assessment is feasible. Despite significant resource constraints, properly science-driven targeted reportages in data-poor countries can bridge the gaps between international scientific knowledge and the implementation of relevant findings in an "awareness-empowerment vortex". When a clear message promoting healthy choices and behaviors is given, African communities are ready to respond. Conclusions: Poor skills are an avoidable consequence of low national income. Narrative prevention does not replace scientific research but stimulates scientific research and toxicological risk analysis during the ongoing risk transition in Africa. While African populations increasingly aspire to improve life expectancy in health, increasing exposure to such new health risk factors in sub-Saharan Africa needs top-down choices for diseases prevention, One Health, as well as public awareness and empowerment towards everyday habits and health protective choices.

Coronavirus disease (COVID-19) and Africa: Acclaimed home remedies

At last the WHO declared the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) now known as COVID-19 a pandemic. Amidst uncertainty both in the pathophysiology and the management of COVID-19, many African countries in the face of either over-stretched or non-existent healthcare infrastructure resorted to home remedies as immediate alternative or first line of action. The present study is a synoptic capture of these home remedies with an attempt to understand the pharmacological basis on which these choices are predicated. Literature was compiled from google, social media, Radio and Television commentaries and news with stringent inclusion and exclusion criteria. Natural spices (turmeric, ginger, garlic etc.) and leaves (neem, paw, guava, etc.) with notable antioxidant and anti-inflammatory properties were found to be beneficial. These home remedies may hold promise in the prophylaxis and cure of COVID-19 infection.