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In a sustainable development concern, the agricultural practices notably those to control the pathogenic and/or mycotoxigenic fungi that maintain the quality and the abundance of crops with respecting the ecosystems and public health are indispensable. Our study focuses on evaluating the biocontrol potential of the actinomycete microflora of some organic amendments against the phytopathogenic and mycotoxigenic Fusarium verticillioides. The inhibitory effect was assessed in term of growth and mycotoxin production (fumonisin FB1 and FB2) of F. verticillioides in the presence of amended soils and selected antagonist agents from the amendments. Results demonstrated that the amended soils with different organic amendments exhibited a higher inhibition rate of Fusarium verticillioides growth than the reference soil. They were able to inhibit the fungal pigment and spore productions which are the major mean of survival and dispersion of this fungus. The fumonisin production was strongly reduced by the metabolites produced by the amended soils’ microbiota, up to 68.7% and 92.5% for FB1 and FB2 respectively. Actinomycete strains isolated from these amendments were identified as Streptomyces and were also tested for their antifungal potential. The fungal growth was reduced up to more than 60% in the presence of extracellular metabolites of several Streptomyces strains. In confrontation assays, most of the Streptomyces strains inhibited strongly both fungal growth and fumonisin production. The FB1 and FB2 amounts were decreased at best, by up to 87.5% and 98.2% respectively, depending on the actinomycete strains and fungal culture time. These results are promising for the use of these biocontrol agents, and especially some actinomycete strains, as tools to reduce fumonisin contamination in cereal crops and derived products.

Cereals products enriched with leguminous or oleaginous are used in Burkina Faso as food complement or to avoid infant malnutrition. Infant formulas from cereals are consumed as food supplements after the weaning age. They are produced in Burkina Faso with a mixture of several cereals (maize, millet, rice, or sorghum), leguminous (bean), oleaginous (peanut, soya or sesame), sugar or salt and sometimes milk powder. The production is artisanal or semi-industrial. These infant foods from cereals should be free from mycotoxins and pathogenic bacteria. The objective of this work was to determine the occurrence of mycotoxins like aflatoxins, ochratoxin A and fumonisins in infant formulas and grains in Ouagadougou (Burkina Faso). The mycotoxins (aflatoxins, ochratoxin A and fumonisins) were determined by HPLC-FLD in 248 samples of infant formulas produced by the Recovery and Nutrition Education Centers (CRENs) and sold on the market places in Burkina Faso. Results showed that the majority of samples of infant formulas presented high levels of mycotoxins. The frequency of contaminated samples by aflatoxin B1, ochratoxin A and fumonisins in analyzed samples were 83.9% (167/199), 7.5% (15/199) and 1.5% (3/199), respectively. The highest values registered in infant formulas were 900, 6 and 3 times higher for aflatoxin B1 (EU limit: 0.1 μg/kg), ochratoxin A (EU limit: 0.5 μg/kg) and fumonisins (EU limit: 200 μg/kg), respectively, than the EU regulation limits (1881/2006). This study presents the first results concerning the safety assessment of infant formulas regarding mycotoxins in Burkina Faso.

Phytopathogenic and/or mycotoxigenic filamentous fungi are involved in a great number of plant diseases that cause yield and quality losses of crops. Besides the economic damages, these fungi produce mycotoxins that present health risks for humans and animals who consume contaminated foods. The most dangerous mycotoxins in the agriculture and the food industry that are regulated in European Union (trichothecenes especially deoxynivalenol, fumonisins, aflatoxins and ochratoxin A) are produced by three main fungal genera ( Fusarium, Aspergillus and Penicillium ). Many approaches have been applied to prevent and manage the phytopathogenic and/or mycotoxigenic fungi. However, these methods involve the use of chemical inputs that are harmful for humans, animals and environment. In a concern of sustainable development, the application of biocontrol has been considered for addressing this problem in a more environmentally friendly way. This review considered the incidence of the three fungal genera and their mycotoxins in crops and in foodstuff. The impacts of the fungal contamination and the toxin accumulation were reported. Besides, the biological control means against these pathogens were reviewed. Among them, organic amendments showed to be effective in both producing antifungal activities and reinforcing plant health.

The effects of light at different wavelengths and photoperiod on growth and ochratoxin A production of Aspergillus carbonarius and Aspergillus westerdijkiae were studied: far-red (740 nm), red (625 nm), blue (445 nm), and UV-A (366 nm). Fungal growth was not significantly affected by photoperiod or light wavelength; the only exception was A. westerdijkiae which showed reduced growth under UV-A light (366 nm). Short-wavelength blue light (445 nm) and UV-A light caused a reduction in ochratoxin A production of both fungal species. However, long-wavelength red light (625 nm) and far-red light (740 nm) reduced ochratoxin A production only in A. westerdijkiae but not in A. carbonarius. It is believed that this difference in reactivity to light is due to differences in the melanin content of the two fungal species: A. carbonarius is a black fungus with higher melanin content than A. westerdijkiae, a yellow fungus. Other possible explanations for the reduction of ochratoxin A production by light were also discussed.

Considering the demand from many industrial sectors, the production of microbial lipids constitutes an attractive topic for research. Oleaginous microorganisms can produce over 60% of their dry matter in single cell oils (SCOs), especially in the form of triglycerides (TAGs). Approximately forty microbial genera, especially yeasts and moulds, are known to be high lipid producers. Many abiotic factors, such as the culture conditions or nutriment availability, influence the production of microbial lipids that are of interest. Among the factors that can influence SCO production, the carbon source, limiting nutriments (especially nitrogen), pH and temperature are cited most often in the literature. Improvement in SCO production through the optimisation of abiotic factors encounters several limitations. Thus, research is currently increasingly oriented toward genetic modifications to optimise the synthesis of lipids by oleaginous microorganisms.

Introduction Ochratoxin A (OTA) is a toxic secondary metabolite produced by fungi of the genera Aspergillus and Penicillium. It has been shown to have carcinogenic and immunotoxic properties in rats and to be responsible for human and animal kidney pathologies. OTA content in coffee was shown to be closely link to harvesting conditions, postharvest processing conditions and especially dry processing, storage and transportation conditions. Purpose Fairly little is known about the conditions for contamination by fungi responsible for OTA production, their propagation and conditions for OTA production. Biodiversity and dynamics of fungal populations linked to OTA production could be studied by PCR-DGGE genetic fingerprinting with the aim to understand the effects of postharvest processing on the microbiota. Results DGGE fingerprints analyzed by multivariate analysis showed an evolution of the fungal microflora of coffee during the different stages of the postharvest treatments (wet and dry processes) by extraction and amplification of 26S (yeasts) and 28S rDNA (filamentous fungi). PCR-DGGE stages were optimized: extraction and amplification, repeatability and sensitivity methodology applied to fungi were tested. Conclusion PCR-DGGE is a rapid molecular technique to monitor the dynamics of coffee microbial populations (fungi and yeast). Significance of study PCR-DGGE is a promising tool in order to investigate OTA production in coffee beans.

Exopolysaccharides (EPSs) produced by microorganisms represent an industrially untapped market. Some microorganisms can produce and excrete over 40 g L −1 of EPS in simple but costly production conditions. Approximately thirty strains of eukaryotic and prokaryotic microorganisms are notable for their EPS production. EPSs are produced in response to biotic and abiotic stress factors and/or to adapt to an extreme environment. The main function of EPSs is to aid in protection against environmental pressures. Heteropolysaccharides and some homopolysaccharides are synthesised in microbial cells and then secreted into the extracellular environment. More currently, homopolysaccharide synthesis occurs outside of the cells after specific enzymes are exuded. Although natural secretory mechanisms exist in microorganisms, it is often necessary to resort to physical or chemical extraction methods to improve the yield of EPSs at an industrial level. In light of growing interest, our basic understanding of microbial EPSs needs to be improved.