The effect of Aspergillus niger as a dietary supplement on blood parameters, intestinal morphology, and gut microflora in Haidong chicks reared in a high altitude environment

Changes in metabolite profiles in solid fermentation of glutamate waste treatment solution by Aspergillus niger and Candida tropicalis

AIMS

Glutamate wastewater poses a great environmental challenge to the monosodium glutamate production industry. However, its treatment solution is rich in crude protein, which has the potential to be developed as a new protein source for animal feed.

METHODS AND RESULTS

Given that the fermentation process generates functionally different metabolites, this study innovatively utilized two strains of feed microorganisms, Aspergillus niger and Candida tropicalis, to perform solid-state fermentation of glutamate wastewater treatment solution. The aim was to investigate and analyse the metabolite profiles during fermentation. The significant differences in metabolite profiles between the samples were determined using correlation analysis, principal component analysis, orthogonal partial least-squares discriminant analysis, variable importance in projection analysis, Kyoto Encyclopaedia of Genomes, and Human Metabolome Data Bank analysis. These variations were mainly manifested in essential feed components, such as amino acids, peptides, and their analogues. These included Ile-Pro-Asn, Pro-Gly-Val, alanylvaline, histidylisoleucine, Lys-Leu-Tyr, Ile-Arg, glycyl-leucine, leucyl-lysine, N-palmitoyl histidine, alanylisoleucine, l-glutamate, N-methylisoleucine, Isoleucylproline, dl-m-tyrosine, Isoleucyl-threonine, phenylalanine amide, carboxyethyllysine, N6-acetyl-l-lysine, citrulline, N-alpha-acetyl-l-lysine, N(6)-methyllysine, and l-aspartate-semialdehyde.

CONCLUSIONS

This study investigates the metabolite profiles of glutamate wastewater treatment solutions after co-fermentation with A. niger and C. tropicalis using solid-state fermentation. These findings provide a new strategy for efficiently utilizing glutamate wastewater treatment solutions.

Evaluation of the synbiotic effects of Saccharomyces cerevisiae and mushroom extract on the growth performance, digestive enzyme activity, and immune status of zebrafish danio rerio

BACKGROUND

The quest for candidate probiotics and prebiotics to develop novel synbiotics for sustainable and profitable fish farming remains a major focus for various stakeholders. In this study, we examined the effects of combining two fungal probiotics, Saccharomyces cerevisiae and Aspergillus niger with extracts of Jerusalem artichoke and white button mushroom to develop a synbiotic formulation to improve the growth and health status of zebrafish (Danio rerio). An initial in vitro study determined the most effective synbiotic combination, which was then tested in a 60-day in vivo nutritional trial using zebrafish (80 ± 1.0 mg) as a model animal. Four experimental diets were prepared: a control diet (basal diet), a prebiotic diet with 100% selected mushroom extract, a probiotic diet with 107 CFU of S. cerevisiae/g of diet, and a synbiotic diet with 107 CFU of S. cerevisiae/g of diet and 100% mushroom extract. As readouts, growth performance, survival, digestive enzyme activity and innate immune responses were evaluated.

RESULTS

In vitro results showed that the S. cerevisiae cultured in a medium containing 100% mushroom extract exhibited the maximum specific growth rate and shortest doubling time. In the in vivo test with zebrafish, feeding them with a synbiotic diet, developed with S. cerevisiae and mushroom extract, led to a significant improvement in the growth performance of zebrafish (P < 0.05). The group of zebrafish fed with the synbiotic diet showed significantly higher levels of digestive enzyme activity and immune responses compared to the control group (P < 0.05).

CONCLUSION

Taken together, these results indicated that the combination of S. cerevisiae and mushroom extract forms an effective synbiotic, capable of enhancing growth performance and immune response in zebrafish.

Research Progress on the Mechanism of Intestinal Barrier Damage and Drug Therapy in a High Altitude Environment

The plateau is a typical extreme environment with low temperature, low oxygen and high ultraviolet rays. The integrity of the intestinal barrier is the basis for the functioning of the intestine, which plays an important role in absorbing nutrients, maintaining the balance of intestinal flora, and blocking the invasion of toxins. Currently, there is increasing evidence that high altitude environment can enhance intestinal permeability and disrupt intestinal barrier integrity. This article mainly focuses on the regulation of the expression of HIF and tight junction proteins in the high altitude environment, which promotes the release of pro-inflammatory factors, especially the imbalance of intestinal flora caused by the high altitude environment. The mechanism of intestinal barrier damage and the drugs to protect the intestinal barrier are reviewed. Studying the mechanism of intestinal barrier damage in high altitude environment is not only conducive to understanding the mechanism of high altitude environment affecting intestinal barrier function, but also provides a more scientific medicine treatment method for intestinal damage caused by the special high altitude environment.

Effect of Dietary Supplementation of Probiotic Aspergillus niger on Performance and Cecal Microbiota in Hy-Line W-36 Laying Hens

This study aimed to investigate the role of the probiotic Aspergillus niger on the production performance, egg quality, and cecal microbial load of Clostridium perfringens, Salmonella spp., and Escherichia coli in Hy-Line W-36 laying hens. A total of 72, 45-week-old Hy-Line W-36 laying hens were randomly allocated to one of the three dietary treatments with six replicates, and each replicate had four individually caged laying hens (n = 6 and 4 hens/replicate). The hens in each treatment group were fed a corn and soybean meal diet (Control), a diet supplemented with bacitracin methylene disalicylate (BMD) at a rate of 495 mg/kg of feed (Positive Control), or a diet supplemented with Aspergillus niger (Probioist®) at a rate of 220 mg/kg of feed (Probiotic). Supplementing probiotics in the laying hen diet significantly increased egg production at weeks 3 and 6 compared with the Positive Control. Haugh unit, a measure of egg quality, was significantly higher in laying hens fed the probiotic diet compared with the Control or Positive Control at week 10. Furthermore, the Probiotic group had numerically lower cecal microbial loads of pathogenic bacteria (Clostridium perfringens, Salmonella spp., and Escherichia coli) compared with the Control and Positive Control groups. The results suggest that Aspergillus niger could be used as a probiotic to improve laying hen performance and egg quality.

Effects of novel microecologics combined with traditional Chinese medicine and probiotics on growth performance and health of broilers

In this study, we prepared a kind of novel microecologics, namely Chinese medicine-probiotic compound microecological preparation (CPCMP), which is composed of 5 traditional Chinese medicine herbs (Galla Chinensis, Andrographis paniculata, Arctii Fructus, Glycyrrhizae Radix, and Schizonepeta tenuifolia) fermented by Aspergillus niger and a kind of compound probiotics (Lactobacillus plantarum A37 and L. plantarum MIII). The effects of the CPCMP in broilers on growth performance, serum parameters, immune function, and intestinal health were investigated. A total of 450 one-day-old male Arbor Acres broilers were randomly divided into 6 treatment groups with 5 replicates, 15 birds per replicate. Treatments consisted of: blank control, CPCMP, positive control, commercial CPCMP, traditional Chinese medicine, and probiotics groups, which were birds fed with basal diet supplemented with no extra additives, 0.2% CPCMP, 0.0035% chlortetracycline, 0.2% commercially available CPCMP, 0.2% fermented traditional Chinese medicines, and 0.2% compound probiotics, respectively. CPCMP obviously increased the average body weight and average daily gain (P < 0.05, compared with any other group) and decreased the feed:gain ratio of broilers (P < 0.05, compared with the blank control, commercial CPCMP, traditional Chinese medicine, or probiotics group). Moreover, it significantly increased glutathione peroxidase and secretory immunoglobulin A levels and spleen/bursa indices (P < 0.05 for all, compared with the blank control, commercial CPCMP, traditional Chinese medicine, or probiotics group). Villus heights in duodenum, jejunum, and ileum were also elevated by CPCMP treatment (P < 0.05, compared with any other group). Furthermore, CPCMP substantially increased jejunal mRNA levels of occludin and zonula occludens-1 (P < 0.05, compared with the blank control, positive control, or probiotics group) and facilitated the growth and colonization of beneficial cecal bacteria, such as Olsenella, Barnesiella, and Lactobacillus. Overall results show that the CPCMP prepared in our work contributes to improving growth performance, serum parameters, immune function, and intestinal health of broilers and exerts synergistic effects of traditional Chinese medicines and probiotics to some extent. Our findings suggest that CPCMP is a promising antibiotic substitute in the livestock and poultry industry in the future.