Effects of Saccharomyces cerevisiae and phytase co-fermentation of wheat bran on growth, antioxidation, immunity and intestinal morphology in broilers

Preliminary characterization of gut mycobiome enterotypes reveals the correlation trends between host metabolic parameter and diet: a case study in the Thai Cohort

The association between the gut mycobiome and its potential influence on host metabolism in the Thai Cohort was assessed. Two distinct predominant enterotypes, Saccharomyces (Sa) and Aspergillus/Penicillium (Ap/Pe) showed differences in gut mycobiota diversity and composition. Notably, the Sa enterotype exhibited lower evenness and richness, likely due to the prevalence of Saccharomyces, while both enterotypes displayed unique metabolic behaviors related to nutrient metabolism and body composition. Fiber consumption was positively correlated with adverse body composition and fasting glucose levels in individuals with the Sa enterotype, whereas in the Ap/Pe enterotype it was positively correlated with fat and protein intake. The metabolic functional analysis revealed the Sa enterotype associated with carbohydrate metabolism, while the Ap/Pe enterotype involved in lipid metabolism. Very interestingly, the genes involved in the pentose and glucuronate interconversion pathway, such as polygalacturonase and L-arabinose-isomerase, were enriched in the Sa enterotype signifying a metabolic capacity for complex carbohydrate degradation and utilization of less common sugars as energy sources. These findings highlight the interplay between gut mycobiome composition, dietary habits, and metabolic outcomes within the Thai cohort studies.

Saccharomyces cerevisiae derived postbiotic alters gut microbiome metabolism in the human distal colon resulting in immunomodulatory potential in vitro

The yeast-based postbiotic EpiCor is a well-studied formulation, consisting of a complex mixture of bioactive molecules. In clinical studies, EpiCor postbiotic has been shown to reduce intestinal symptoms in a constipated population and support mucosal defense in healthy subjects. Anti-inflammatory potential and butyrogenic properties have been reported in vitro, suggesting a possible link between EpiCor's gut modulatory activity and immunomodulation. The current study used a standardized in vitro gut model, the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®), to obtain a deeper understanding on host-microbiome interactions and potential microbiome modulation following repeated EpiCor administration. It was observed that EpiCor induced a functional shift in carbohydrate fermentation patterns in the proximal colon environment. Epicor promoted an increased abundance of Bifidobacterium in both the proximal and distal colon, affecting overall microbial community structure. Co-occurrence network analysis at the phylum level provided additional evidence of changes in the functional properties of microbial community promoted by EpiCor, increasing positive associations between Actinobacteria with microbes belonging to the Firmicutes phylum. These results, together with a significant increase in butyrate production provide additional support of EpiCor benefits to gut health. Investigation of host-microbiome interactions confirmed the immunomodulatory potential of the applied test product. Specific microbial alterations were observed in the distal colon, with metabotyping indicating that specific metabolic pathways, such as bile acid and tryptophan metabolism, were affected following EpiCor supplementation. These results, especially considering many effects were seen distally, further strengthen the position of EpiCor as a postbiotic with health promoting functionality in the gut, which could be further assessed in vivo.

Effects of Dietary Bacillus coagulans and Tributyrin on Growth Performance, Serum Antioxidants, Intestinal Morphology, and Cecal Microbiota of Growing Yellow-Feathered Broilers

This study investigated the impact of Bacillus coagulans (BC) and tributyrin (TB) supplementation on the growth performance, serum antioxidant capacity, intestinal morphology, and cecal microbiota of yellow-feathered broilers. Using a 2 × 2 factorial design, 480 broilers were randomly assigned to four experimental diets, comprising two levels of BC (0 and 1 g/kg) and two levels of TB (0 and 1 g/kg), over a 36-day period. A significant interaction was observed between BC and TB, impacting the average daily feed intake (ADFI) of broilers aged between 26 and 40 days (p < 0.01). BC and TB also displayed a significant interaction in relation to serum malondialdehyde levels and total antioxidant capacity (p < 0.05). Additionally, there was a significant interaction between BC and TB concerning the duodenal villus-to-crypt ratio, crypt depth, and jejunal villus-to-crypt ratio (p < 0.05). The addition of BC and TB significantly enhanced the richness and diversity of cecal microbiota, with a notable interactive effect observed for the abundance of Faecalibacterium, Ruminococcus_torques_group, and Phascolarctobacterium. In conclusion, supplementation with BC and TB can effectively improve the growth performance, serum antioxidant capacity, intestinal morphology, and cecal microbiota composition of yellow-feathered broilers, indicating the presence of an interactive effect.

Impact of Lactobacillus apis on the antioxidant activity, phytic acid degradation, nutraceutical value and flavor properties of fermented wheat bran, compared to Saccharomyces cerevisiae and Lactobacillus plantarum

This study aimed to use a novel Lactobacillus strain (L. apis) isolated from the bee gut to develop a wheat bran (WB) deep-processing technology. Compared to the most popular strains (S. cerevisiae and L. plantarum), we found that L. apis had a greater ability to enhance the fermented WB antioxidant activity through hydroxyl radical scavenging, metal chelating ability, reducing power, and ferric reducing antioxidant power. While L. apis and L. plantarum had similar effects on DPPH^• and ABTS^•+ scavenging activities. This improvement in antioxidant activity has been associated with some metabolic compounds, such as sinapic acid, hydroferulic acid, pyruvic acid, neocostose, oxalic acid, salicylic acid, and schaftoside. Furthermore, L. apis degraded 48.33% of the phytic acid in WB, higher than S. cerevisiae (26.73%) and L. plantarum (35.89%). All strains improved the volatile profile of WB, and the fermented WB by each strain displayed a unique volatile composition. L. apis increased the level of conditional amino acids and branched-chain amino acids significantly. S. cerevisiae increased γ-aminobutyric acid the most, from 230.8 mg/L in unfermented samples to 609.8 mg/L in the fermented WB. While L. apis and L. plantarum also increased the level of γ-aminobutyric acid to 384.5 mg/L and 295.04 mg/L, respectively. Finally, we found that L. apis remarkably increased the content of organic acids and water-soluble vitamins in wheat bran.

Effects of Saccharomyces cerevisiae hydrolysate on growth performance, immunity function, and intestinal health in broilers

The current study was performed to explore the effects of dietary supplementation of Saccharomyces cerevisiae hydrolysate (SCH) on growth performance, immune function, and intestinal health in broiler chicken. A total of 300 Ross 308 male broilers (1-day-old) were randomly assigned to 2 dietary treatments including a basal diet (control group), and a basal diet supplemented with SCH feed additive (500 mg/kg in starter and grower phase, and 250 mg/kg in finisher phase). Each treatment had 6 replicates with 25 birds each. The results showed that the addition of SCH promoted growth during d 15 to 28 (P < 0.05). Although the addition of SCH had no significant effect on the intestinal relative indexes, it significantly increased the jejunum villus height (VH) and the ratio of villus height to crypt depth (VCR) of jejunum, and decreased the crypt depth (CD) of ileum (P < 0.05). Furthermore, SCH addition significantly downregulated the mRNA expression of immunomodulatory genes (TNF-α, IL-1β, and IL-6), and upregulated the tight junction genes (ZO-1 and Claudin-1) (P < 0.05). High throughput sequencing analysis of bacterial 16S rRNA revealed that dietary SCH supplementation altered cecum microbiota. Alpha diversity analysis showed that a higher bacterial richness in cecum of broilers fed with SCH. The composition of cecum microbiota regulated by SCH addition was characterized by an increased abundance of Firmicutes and a reduced abundance of Bacteroidetes. At the genus level, dietary SCH resulted in a decrease of Bacteroides and an increase of short-chain fatty acids (SCFA) -producing bacteria including Lactobacillus and Faecalibacterium. Taken together, dietary SCH supplementation can stimulate the growth of broilers by regulating the intestinal immunity and barrier function, and improving the intestinal morphology, which may be related to the enhancement of bacterial diversity and the changes of intestinal microbial composition.

Yeast-Derived Products: The Role of Hydrolyzed Yeast and Yeast Culture in Poultry Nutrition—A Review

Simple Summary

Yeast and yeast-derived products are largely employed in animal nutrition to support animals’ health and to improve their performance. Thanks to their components, including mannans, β-glucans, nucleotides, vitamins, and other compounds, yeasts have numerous beneficial effects. Among yeast-derived products, hydrolyzed yeasts and yeast cultures have received less attention, but, although the results are somewhat conflicting, in most of the cases, the available literature shows improved performance and health in poultry. Thus, the aim of this review is to provide an overview of hydrolyzed-yeast and yeast-culture employment in poultry nutrition, exploring their effects on the production performance, immune response, oxidative status, gut health, and nutrient digestibility. A brief description of the main yeast bioactive compounds is also provided.

Abstract

Yeasts are single-cell eukaryotic microorganisms that are largely employed in animal nutrition for their beneficial effects, which are owed to their cellular components and bioactive compounds, among which are mannans, β-glucans, nucleotides, mannan oligosaccharides, and others. While the employment of live yeast cells as probiotics in poultry nutrition has already been largely reviewed, less information is available on yeast-derived products, such as hydrolyzed yeast (HY) and yeast culture (YC). The aim of this review is to provide the reader with an overview of the available body of literature on HY and YC and their effects on poultry. A brief description of the main components of the yeast cell that is considered to be responsible for the beneficial effects on animals’ health is also provided. HY and YC appear to have beneficial effects on the poultry growth and production performance, as well as on the immune response and gut health. Most of the beneficial effects of HY and YC have been attributed to their ability to modulate the gut microbiota, stimulating the growth of beneficial bacteria and reducing pathogen colonization. However, there are still many areas to be investigated to better understand and disentangle the effects and mechanisms of action of HY and YC.

Modulation of Gut Microbiota and Immune System by Probiotics, Pre-biotics, and Post-biotics

The human gastrointestinal tract harbours a complex microbial community, which interacts with the mucosal immune system closely. Gut microbiota plays a significant role in maintaining host health, which could supply various nutrients, regulate energy balance, modulate the immune response, and defence against pathogens. Therefore, maintaining a favourable equilibrium of gut microbiota through modulating bacteria composition, diversity, and their activity is beneficial to host health. Several studies have shown that probiotics and pre-biotics could directly and indirectly regulate microbiota and immune response. In addition, post-biotics, such as the bioactive metabolites, produced by gut microbiota, and/or cell-wall components released by probiotics, also have been shown to inhibit pathogen growth, maintain microbiota balance, and regulate an immune response. This review summarises the studies concerning the impact of probiotics, pre-biotics, and post-biotics on gut microbiota and immune systems and also describes the underlying mechanisms of beneficial effects of these substances. Finally, the future and challenges of probiotics, pre-biotics, and post-biotics are proposed.

The Potential Utilization of High-Fiber Agricultural By-Products as Monogastric Animal Feed and Feed Additives: A Review

With the increase in world food demand, the output of agricultural by-products has also increased. Agricultural by-products not only contain more than 50% dietary fiber but are also rich in functional metabolites such as polyphenol (including flavonoids), that can promote animal health. The utilization of dietary fibers is closely related to their types and characteristics. Contrary to the traditional cognition that dietary fiber reduces animal growth, it can promote animal growth and maintain intestinal health, and even improve meat quality when added in moderate amounts. In addition, pre-fermenting fiber with probiotics or enzymes in a controlled environment can increase dietary fiber availability. Although the use of fiber has a positive effect on animal health, it is still necessary to pay attention to mycotoxin contamination. In summary, this report collates the fiber characteristics of agricultural by-products and their effects on animal health and evaluates the utilization value of agricultural by-products.