In this study, the effects of several key factors to increase spore production by Bacillus subtilis subsp. KATMIRA 1933 were evaluated in shake flask experiments. In a synthetic medium, glucose concentration played a crucial role in the expression of bacilli sporulation capacity. In particular, maximum spore yield (2.3 × 10 spores/mL) was achieved at low glucose concentration (2 g/L), and further gradual increase of the carbon source content in the medium caused a decrease in sporulation capacity. Substitution of glucose with several inexpensive lignocellulosic materials was found to be a reasonable way to achieve high cell density and sporulation. Of the materials tested, milled mandarin peels at a concentration of 40 g/L served as the best growth substrate. In these conditions, bacilli secreted sufficient levels of glycosyl hydrolases, providing slow hydrolysis of the mandarin peel's polysaccharides to metabolizable sugars, providing the bacterial culture with an adequate carbon and energy source. Among nitrogen sources tested, peptone was found to favor spore production. Moreover, it was shown that cheese and cottage cheese whey usage, instead of distilled water, significantly increases spore formation. After optimization of the nutrient medium in the shake flask experiments, the technical feasibility of large-scale spore production by B. subtilis KATMIRA 1933 was confirmed in a laboratory fermenter. The spore yield (7 × 10 spores/mL) obtained using a bioreactor was higher than those previously reported.

This study was conducted to elucidate cultivation conditions determining Bacillus amyloliquefaciens B-1895 growth and enhanced spore formation during the solid-state fermentation (SSF) of agro-industrial lignocellulosic biomasses. Among the tested growth substrates, corncobs provided the highest yield of spores (47 × 10 spores g biomass) while the mushroom spent substrate and sunflower oil mill appeared to be poor growth substrates for spore formation. Maximum spore yield (82 × 10 spores g biomass) was achieved when 15 g corncobs were moistened with 60 ml of the optimized nutrient medium containing 10 g peptone, 2 g KHPO, 1 g MgSO·7HO, and 1 g NaCl per 1 l of distilled water. The cheese whey usage for wetting of lignocellulosic substrate instead water promoted spore formation and increased the spore number to 105 × 10 spores g. Addition to the cheese whey of optimized medium components favored sporulation process. The feasibility of developed medium and strategy was shown in scaled up SSF of corncobs in polypropylene bags since yield of 10 × 10 spores per gram of dry biomass was achieved. In the SSF of lignocellulose, B. amyloliquefaciens B-1895 secreted comparatively high cellulase and xylanase activities to ensure good growth of the bacterial culture.

The aim of this study was to gain a deeper fundamental knowledge on the physiology of B. amyloliquefaciens B-1895 for development of probiotic production technology through the submerged fermentation of renewable and inexpensive agro-industrial lignocellulosic biomass. For comparison, bacilli cultivation was performed in the synthetic medium with different carbon sources. The highest yield of spores (7.1 x 109/mL) was attained after 72 h of submerged cultivation of bacilli in the 0.4% glucose-containing medium. Substitution of glucose with various lignocellulosic materials at concentration of 40 g/L yielded 2.3-10.8 x 109 spores/mL. After subsequent optimization, the developed simple medium containing milled corn cobs as a growth substrate and casein hydrolysate at concentration of 40 mM N provided formation of as high as 2.8 x 1010 spore/mL in shake-flasks experiments and 2.5 x 1010 spores/mL in a laboratory fermenter enabling the large scale production of low-cost probiotic for their biotechnological application. The study underlines importance for the efficient sporulation of carbon source depletion at the end of the exponential growth phase. Moreover, it shows that an exploitation of lignocellulosic materials with an appropriate chemical composition is a reasonable way to achieve high cell density and sporulation since bacilli secrete sufficient levels of glycosyl hydrolases for substrate saccharification to ensure bacterial culture with carbon and energy source.

The EU's European Neighbourhood Policy (ENP) promotes stability, security and prosperity in neighbouring countries. It builds on common interests and a shared commitment to cooperate on key priority areas including food safety. This technical report presents a summary of an online workshop held on 4 November 2020, with East European Neighbourhood (ENP‐East) countries and contributions from the World Health Organization (WHO), the European Commission (DG SANTE and DG‐NEAR), the German Federal Institute for Risk Assessment (Bundesinstitut für Risikobewertung, BfR) and the Institute of Food safety, Animal Health and Environment "BIOR" of Latvia.The aim of the workshop was to present the current status of risk assessment activities in the six ENP‐East countries (Armenia, Azerbaijan, Belarus, Georgia, Moldova and Ukraine), discuss the challenges they face and explore opportunities for cooperation with the European Union (EU) and other international organisations. A summary of the presentations is provided along with relevant key risk assessment activities in each country. Contributions from EFSA and the WHO are also included. Opportunities and challenges for the food safety area are discussed particularly to further enhance risk assessment capabilities in ENP countries through cooperation, capacity building and staff exchange between ENP, EU and international organisations as the most efficient tools to achieve such goals.

The potential of wood-rotting and litter-deconstructing basidiomycetes to convert lignocellulose into a wide variety of products has been extensively studied. In particular, wood-rotting basidiomycete secretomes are attracting much attention from researchers and biotechnology companies due to their ability to produce extracellular hydrolytic and oxidative enzymes that effectively degrade cellulose, hemicellulose, and lignin of plant biomass. An analysis of the available literature data shows that Basidiomycota fungi, which are most adapted to the depolymerization of plant polysaccharides, are promising but so far unexploited sources of new hydrolytic enzymes. The review summarizes the latest data on the great variety, common features, and unique properties of individual fungi and the production of cellulases and xylanases by various physiological and ecological groups of basidiomycetes. The most important microbial cellulase-producing strains for submerged and solid-phase fermentation, as well as the main substrates, including the use of agro-industrial waste, are considered. It highlights ways to increase both cellulase and xylanase expression levels and the cost-effectiveness of producing these enzymes for various biotechnological applications. It is anticipated that this review will be particularly useful to novice scientists working in the lignocellulose biorefinery, as it describes current knowledge and issues related to the production and regulation of polysaccharide hydrolyzing enzyme synthesis.