A new strategy to apply Bacillus subtilis MA139 for the production of solid-state fermentation feed

Bioremediation of Aflatoxin B1 by Meyerozyma guilliermondii AF01 in Peanut Meal via Solid-State Fermentation

The use of microorganisms to manage aflatoxin contamination is a gentle and effective approach. The aim of this study was to test the removal of AFB1 from AFB1-contaminated peanut meal by a strain of Meyerozyma guilliermondii AF01 screened by the authors and to optimize the conditions of the biocontrol. A regression model with the removal ratio of AFB1 as the response value was established by means of single-factor and response surface experiments. It was determined that the optimal conditions for the removal of AFB1 from peanut meal by AF01 were 75 h at 29 °C under the natural pH, with an inoculum of 5.5%; the removal ratio of AFB1 reached 69.31%. The results of simulating solid-state fermentation in production using shallow pans and fermentation bags showed that the removal ratio of AFB1 was 68.85% and 70.31% in the scaled-up experiments, respectively. This indicated that AF01 had strong adaptability to the environment with facultative anaerobic fermentation detoxification ability. The removal ratio of AFB1 showed a positive correlation with the growth of AF01, and there were no significant changes in the appearance and quality of the peanut meal after fermentation. This indicated that AF01 had the potential to be used in practical production.

The process of solid-state fermentation of soybean meal: antimicrobial activity, fermentation heat generation and nitrogen solubility index

BACKGROUND

Bacillus amyloliquefaciens has excellent protease production ability and holds great prospects for application in the solid-state fermentation of soybean meal (SBM).

RESULTS

Among eight strains of bacteria, Bacillus amyloliquefaciens subsp. plantarum CICC 10265, which exhibited higher protease production, was selected as the fermentation strain. The protease activity secreted by this strain reached 106.41 U mL-1 . The microbial community structure differed significantly between natural fermentation and inoculation-enhanced fermented soybean meal (FSBM), with the latter showing greater stability and inhibition of miscellaneous bacterial growth. During fermentation, the temperature inside the soybean meal increased, and the optimal environmental temperature for FSBM was found to be between 35 and 40 °C. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and nitrogen solubility index (NSI) results demonstrated that solid-state fermentation had a degrading effect on highly denatured proteins in SBM, resulting in an NSI of 67.1%.

CONCLUSION

Bacillus amyloliquefaciens subsp. plantarum CICC 10265 can enhance the NSI of SBM in solid-state fermentation and inhibit the growth of miscellaneous bacteria. © 2023 Society of Chemical Industry.

Advances in research on solid-state fermented feed and its utilization: The pioneer of private customization for intestinal microorganisms

With sustainable development of biotechnology, increasing attention has been placed on utilization of solid-state fermented feed (SFF). Solid-state fermented feed has been a candidate strategy to alleviate the contradiction between supply and demand of feed resources, ensure food hygiene safety, promoting energy conservation, and emission reduction. In production of SFF, a variety of organic acids, enzymes, vitamins, peptides, and other unknown growth factors are produced, which could affect performance of animals. Solid-state fermented feed produced by different fermentation techniques has great instability on different physiological stages of different animals, which hinders the application and standardized production of SFF. Herein, we summarize the current advances in the role of the characteristics of SFF prepared by different manufacturing technique and its research progress in animal experiments on growth performance, gastrointestinal ecology, and immune system, so as to provide references for further acquiring a relatively perfect set of SFF production and evaluation systems.

Recent Advances in the Physiology of Spore Formation for Bacillus Probiotic Production

Spore-forming probiotic bacteria have received a wide and constantly increasing scientific and commercial interest. Among them, Bacillus species are the most studied and well-characterized Gram-positive bacteria. The use of bacilli as probiotic products is expanding especially rapidly due to their inherent ability to form endospores with unique survivability and tolerance to extreme environments and to produce a large number of valuable metabolites coupled with their bio-therapeutic potential demonstrating immune stimulation, antimicrobial activities and competitive exclusion. Ease of Bacillus spp. production and stability during processing and storage make them a suitable candidate for commercial manufacture of novel foods or dietary supplements for human and animal feeds for livestock, especially in the poultry and aquaculture industries. Therefore, the development of low-cost and competitive technologies for the production of spore-forming probiotic bacteria through understanding physiological peculiarities and mechanisms determining the growth and spore production by Bacillus spp. became necessary. This review summarizes the recent literature and our own data on the physiology of bacilli growth and spore production in the submerged and solid-state fermentation conditions, focusing on the common characteristics and unique properties of individual bacteria as well as on several approaches providing enhanced spore formation.

Method of preparation, visualization and ultrastructural analysis of a formulation of probiotic Bacillus subtilis KATMIRA1933 produced by solid-phase fermentation

Probiotic preparations are used in medical treatment and in agricultural practice. They modulate numerous activities in eukaryotic hosts, such as: inhibition of pathogenic microbiota; stimulation of immunological responses; and production of antioxidants, anti-mutagens, and DNA protectors. Also, probiotic bacteria are used as a preventive measure to prevent bacterial diseases of the gastrointestinal tract. Solid-phase fermentation is reported as being used in the production of probiotic formulations where a solid substratum, such as soy and oil meal, is utilized for the growth of beneficial microorganisms. However, there are insufficient reports in the literature related to methodological approaches enabling evaluation of the final products of solid-phase fermentation. We suggest a novel method enabling evaluation of probiotic solid-state fermentation dry powders and observation of their morphology, ultrastructure, and elucidation of the quantitative distribution of probiotic microorganisms in solid substrates using electron microscopy. •The method is intended for ultrastructure microphotography of dry substances - for example, ultrastructure of solid-phase fermentation products.•The method allows preserving the ultrastructure of substrates that are damaged when soaking.•The method does not require additional equipment and reagents and can be used in all laboratories using electron microscopy.

Optimization of Mixed Solid-state Fermentation of Soybean Meal by Lactobacillus Species and Clostridium butyricum

Soybean meal is the main vegetable protein source in animal feed. Soybean meal contains several anti-nutritional factors, which directly affect digestion and absorption of soy protein, thereby reducing growth performance and value in animals. Fermented soybean meal is rich in probiotics and functional metabolites, which facilitates soybean protein digestion, absorption and utilization in piglets. However, the mixed solid-state fermentation (SSF) conditions of soybean meal remain to be optimized. In this study, we investigated the optimal parameters for SSF of soybean meal by Lactobacillus species and Clostridium butyricum . The results showed that two days of fermentation was sufficient to increase the viable count of bacteria, lactic acid levels and degradation of soybean protein in fermented soybean meal at the initial moisture content of 50%. The pH value, lowering sugar content and oligosaccharides in fermented soybean meal, was significantly reduced at the initial moisture content of 50% after two days of fermentation. Furthermore, the exogenous proteases used in combination with probiotics supplementation were further able to enhance the viable count of bacteria, degradation of soybean protein and lactic acid level in the fermented soybean meal. In addition, the pH value and sugar content in fermented soybean meal were considerably reduced in the presence of both proteases and probiotics. Furthermore, the fermented soybean meal also showed antibacterial activity against Staphylococcus aureus and Escherichia coli . These results together suggest that supplementation of both proteases and probiotics in SSF improves the nutritional value of fermented soybean meal and this is suitable as a protein source in animal feed.

The effects of fermentation and enzymatic treatment of pea on nutrient digestibility and growth performance of broilers

The present study examined the impacts of native, fermented or enzymatically treated peas (Pisum sativum L.) inclusion in broiler diets, on growth performance and nutrient digestibility. For the fermentation process, Madonna pea was mixed with water (1/1) containing 2.57×108 Bacillus subtilis (GalliPro®) spores/kg pea and then, incubated for 48 h at 30 °C. For the enzymatic treatment process, the used water for dough production contained three enzymes, AlphaGalTM (α-galactosidase), RONOZYME® ProAct and VP (protease and pectinases respectively - DSM, Switzerland) and the pea dough incubated for 24 h at 30°C. Nine corn-wheat-soybean diets were formulated by supplying 10%, 20% and 30% of the required CP with either native, fermented or enzymatically treated peas. Performance was recorded weekly and at the end of the experiment (day 35), apparent ileal digestibility (AID) of CP, amino acids (AA), crude fat, starch, Ca, P and K were determined. Data were subjected to ANOVA using GLM procedure with a 3×3 factorial arrangement of treatments. Both processes reduced α-galactosides, phytate, trypsin inhibitor activity and resistant starch in peas. Increasing levels of pea products up to 300 g/kg diet, reduced BW gain and feed intake (P⩽0.05). Broilers fed diets containing enzymatically treated pea had the best feed conversion ratio at day 35. Different types of pea product and their inclusion levels had no effect on AID of all nutrients. The interaction between type of the pea products and inclusion levels was significant for AID of starch. For native pea diets, 10% group showed similar AID of starch to 20% native pea but it had higher AID than 30% native pea. For fermented and enzymatically treated groups, all three levels displayed similar AID of starch. In conclusion, enzymatic treatment and fermentation could improve the nutritional quality of pea. Inclusion of enzymatically treated pea in broiler diets could improve broiler performance compared with other pea products while, it displayed neither positive nor negative impact on nutrient digestibility. The present findings indicate the feasibility of these processes, particularly enzymatic treatment, for improving the nutritional quality of pea as a protein source for broiler nutrition.

Energy and ileal digestible amino Acid concentrations for growing pigs and performance of weanling pigs fed fermented or conventional soybean meal

A new strategy of co-inoculating Bacillus subtilis MA139 with Streptococcus thermophilus and Saccharomyces cerevisiae was used to produce fermented soybean meal (FSBM). Three experiments were conducted to determine the concentration of digestible energy (DE) and metabolizable energy (ME) (Exp. 1), apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) (Exp. 2), and feeding value (Exp. 3) of FSBM produced by this new strategy (NFSB) compared with soybean meal (SBM) and conventionally available FSBM (Suprotein). In Exp. 1, twenty-four barrows (initial body weight [BW] of 32.2 ±1.7 kg) were randomly allotted to 1 of 4 diets with 6 replicates per diet. A corn basal diet and 3 diets based on a mixture of corn and 1 of 3 soybean products listed above were formulated and the DE and ME contents were determined by the difference method. The results showed that there were no differences in DE and ME between SBM and either FSBM product (p>0.05). In Exp. 2, eight barrows (initial BW of 26.8±1.5 kg) were fitted with ileal T-cannulaes and used in a replicated 4×4 Latin square design. Three corn-starch-based diets were formulated using each of the 3 soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. The results showed that the SID of all AA except arginine and histidine was similar for NFSB and SBM (p>0.05), but Suprotein had greater (p<0.05) SID of most AA except lysine, aspartate, glycine and proline than NFSB. In Exp. 3, a total of 144 piglets (initial BW of 8.8±1.2 kg) were blocked by weight and fed 1 of 4 diets including a control diet with 24% SBM as well as diets containing 6% and 12% NFSB or 12% Suprotein added at the expense of SBM. During d 15 to 28, replacing SBM with 6% NFSB significantly improved average daily gain (ADG) and average daily feed intake (ADFI) (p<0.05) for nursery piglets. During the overall experiment, ADG of piglets fed diets containing 6% NFSB was significantly greater (p<0.05) than that of piglets fed SBM. In conclusion, fermentation with the new strategy did not affect the energy content or the AID and the SID of AA in SBM. However, inclusion of 6% NFSB in diets fed to nursery piglets improved performance after weaning likely as a result of better nutritional status and reduced immunological challenge.

Precursor supply strategy for tetramethylpyrazine production by bacillus subtilis on solid-state fermentation of wheat bran

Tetramethylpyrazine (TTMP) is a widely used flavoring additive with a nutty and roasted taste. Solid-state fermentation (SSF) of wheat bran for producing TTMP was studied with Bacillus subtilis CCTCC M208157, which was an exogenous precursor-independent TTMP-producing strain. Factors influencing endogenous precursor supply and TTMP formation in this strain were investigated. According to the findings, glucose and diammonium phosphate contributed to TTMP production but excess salts caused an inhibition on cell growth and TTMP formation. Then a two-step supply strategy was applied: 10 % glucose was added at the beginning of the process to allow acetoin formation, which was the precursor of TTMP, while 3 % diammonium phosphate was added only after acetoin accumulation reached its maximum. By applying this strategy, acetoin increased from 5.44 to 13.2 g/kg dry substrate (kgds), and consequently the yield of TTMP increased by 6.8 folds from 0.44 to 3.01 g/kgds. This was the first report of using a two-step supply strategy for TTMP production by SSF, which proved to be conducive to TTMP production in this strain.