Probiotic Bacillus Research Articles

Isolation and identification of probiotic Bacillus subtilis AJQ03 from the intestinal tract of Anguilla japonica (Japanese eel)

In recent years, the use of fish-derived probiotics in aquaculture has become more widespread. However, research on Anguilla japonica-derived probiotics is still limited. To evaluate the potential of probiotics for disease control in eel aquaculture, isolates were obtained from the intestinal tract of healthy Anguilla japonica. These isolates were assessed for their adhesion properties, inhibition of pathogen adhesion, and hydrolytic enzyme production. Morphological characteristics and 16S rRNA sequence analysis were used for identification. Results showed that the AJQ03 strain adhered to the intestinal mucus and inhibited common pathogenic bacteria through adhesion inhibition, and further produced amylase, lipase, protease, and cellulase. Based on morphological characteristics and 16S rRNA sequencing, AJQ03 was identified as Bacillus subtilis. The strain demonstrated tolerance to various extreme conditions, as well as survival in simulated gastrointestinal fluids and superior growth in intestinal fluid compared to Luria-Bertani (LB) broth. In vitro safety tests showed that AJQ03 was not resistant to 32 antibiotics and exhibited γ hemolysis on blood plate. In vivo safety tests demonstrated a 100% survival rate for the fish, with stable organ indices, reduced bacterial loads in the liver and spleen, and complete bacterial clearance by day 7 without residue. Intestinal bacterial load results confirmed effective colonization by strain AJQ03. Analysis of the impact of AJQ03 on the gut microbiota of A. japonica revealed a significant increase in the relative abundance of Bacillus at the genus level, corroborating the colonization efficiency of AJQ03. Additionally, the relative abundances of Klebsiella, Pseudomonas, and Aeromonas were significantly lower compared to the controls, indicating that strain AJQ03 effectively reduced harmful bacteria and improved gut microbiota composition. This study confirms that B. subtilis AJQ03, isolated from the intestine of A. japonica, can serve as a probiotic candidate in A. japonica aquaculture.

Effects of three different strains of Bacillus-based probiotics and Saccharomyces cerevisiae-based prebiotic on performance, egg components and gene expression of laying hens during phase II of production

This study aimed to investigate the impacts of three strains of probiotics (Bacillus spp. (B.)) and one prebiotic based on Saccharomyces cerevisiae cell wall (SCCW) supplements on performance, egg quality and immune-related gene expression of laying hens. The experiment lasted 16 weeks (52–68 weeks), during which 450 Hisex white layers at 52 weeks were randomly allocated into five dietary regimens (five replications of 18 birds per floor pen): T1, basal diet; T2, basal + 0.5 g/kg B. subtilis (DSM17299); T3, basal + 0.5 g/kg B. subtilis (DSM 5750) and B. licheniformis (DSM 5749); T4, basal + 0.4 g/kg B. subtilis PB6; and T5, basal + 0.25 g/kg SCCW. The results showed that hen-day egg production (HDEP) improved in T4 and T5, egg mass (EM) improved in T3, T4 and T5, and feed conversion ratio (FCR) improved in T4 and T5 compared to T1 (p < .001). Relative wet and dry yolk weight were higher in hens received T2, T4 and T5 (p < .05) and T2, T3, T4 and T5 (p < .001), respectively, compared to T1. Moreover, T2, T4 and T5 had higher expression of GnRH-2 gene compared to T1 (p < .01). In conclusion, the dietary inclusion of SCCW-based prebiotic (T5) and Bacillus spp. probiotic strains, especially T4 B. subtilis PB6 improved production performance, egg components and GnRH-II gene expression of laying hens during phase II of the production cycle and hold a great promise for boosting productivity and supporting health status of layers raised on AGPs-free diets.

Micromanagement: conditions influencing antipathogen function of the skin microbiome in spotted salamanders, Ambystoma maculatum

The emerging fungal pathogen Batrachochytrium salamandrivorans (Bsal) threatens the diversity of amphibians, particularly in North America where it is projected to invade. Amphibian skin defenses include a mucosal layer containing microorganisms that can potentially modulate host response to pathogens such as Bsal. In this study, we focused on the composition of the skin microbiome across life stages of spotted salamanders (Ambystoma maculatum). We also evaluated the stress hormone corticosterone and skin microbiome response to inoculations with Bsal and probiotics at both the larval and juvenile developmental stages, and the response to different environmental conditions. Results indicated that both bacterial and fungal communities found on the skin significantly differed in structure and diversity between life stages of A. maculatum. Exposure to three different probiotics (Bacillus thuringiensis, Chryseobacterium rhizoplanae, and Penicillium sp.) and Bsal evoked shifts in the microbiome of larvae and juveniles, and the metabolite profile of the larval mucosal layer of A. maculatum. Despite changes in the microbiome, all tested probiotics and Bsal were unable to persist on the skin. Larval bacterial microbiomes shifted in response to Bsal and B. thuringiensis with no significant impacts on antifungal function or bacteria richness, however fungi strongly responded to Bsal and B. thuringiensis application. This indicates that developmental shifts in the microbiome can be initiated by microbial applications such as B. thuringiensis, a widely used mosquito larvicide. Overall, experimental results indicate that life stage, growth and development, and environmental conditions appeared to be the main factors driving changes in the amphibian skin microbiome and potential anti-Batrachochytrium function.

Effect of Probiotic Supplementation in Diet on Egg Production, Egg Quality, Intestinal Morphology and Bacterial Population in Caecum of Laying Hens

The objective of this study was to study the effect of probiotic supplementation in diet on egg production, egg quality, intestinal morphology, and bacterial population in caecum of laying hens. A total of 768 Lohmann Brown-Classic laying hens, aged 42 - 54 weeks, were used. The laying hens were divided into 3 groups, each with 8 subgroups of 32 birds each. The experiment was planned to use a completely randomized design method. The 3 experimental groups were classified based on their dietary treatment as follows: 1) Basal diet (without probiotic supplementation), 2) Basal diet with probiotic 0.01 and 0.02 % in 3, respectively. Data was collected for 12 weeks. Adding probiotic in the diet was no significant difference on egg production, egg quality, and bacterial population in caecum. However, probiotic supplementation in the diet increased villi height of the duodenum significantly improved (p &lt; 0.02), villi height per depth crypt of the duodenum significantly improved (p &lt; 0.05), villi height per depth crypt of the jejunum significantly improved (p &lt; 0.01), and villi height per depth crypt of the ileum significantly improved (p &lt; 0.02). Therefore, studies have shown that dietary probiotic supplementation can improved small intestinal morphology are the most important indexes for measuring the digestive and absorption function of the small intestine are more efficient. HIGHLIGHTS Probiotic (Bacillus subtilis) is a gram-positive, non-pathogenic bacterium that can inhibit digestive enzymes such as protease, amylase, and lipase. These enzymes help increase the efficiency of digestion and absorption of nutrients. As a result of the working mechanism of Bacillus subtilis, it helps strengthen the intestinal wall, eliminates pathogenic microorganisms, reduces damaged intestinal mucosal cells, and improves intestinal absorption, resulting in increased production. Effect of probiotic (Bacillus subtilis) supplementation in laying hen diets on total bacterial load in appendix. No difference was found in the load of total bacteria and Escherichia coli (P &gt; 0.05). Its beneficial properties stimulate the growth of beneficial bacteria in the intestines, such as Bifidobacteria sp. and Lactobacillus sp., causing the production of lactic acid, which makes the colon more acidic, resulting in inhibition of the growth of pathogenic microorganisms. GRAPHICAL ABSTRACT

The comparative effects of probiotics on growth, antioxidant indices and intestinal histomorphology of broilers under heat stress condition.

Heat stress adversely affects both the productivity and well-being of chickens. Probiotics offer beneficial impacts on the health and growth performance of broilers. The current study investigates the influence of administering of Bacillus (including B. subtilis, B. licheniformis, B. coagulans, and B. indicus) and Lactobacillus (consisting of L. acidophilus, L. plantarum, L. buchneri, and L. rhamnosus) probiotics via drinking water, either singular or combined, on various aspects including growth performance, oxidative stress markers, carcass characteristics, fecal microbial composition, intestinal structure, and intestinal pH in broilers exposed to chronic heat stress. A total of 150 one-day-old broiler chicks were divided into 5 groups: (1) NC, negative control; (2) HS, birds exposed to chronic heat stress; (3) HSpBacil, exposed to chronic heat stress and received Bacillus probiotic; (4) HSpLAB, subjected to chronic heat stress and provided with Lactobacillus probiotic; (5) HSpMix, subjected to chronic heat stress and administered a combined probiotic from Bacillus and Lactobacillus. The HS group exhibited significantly reduced levels of growth performance, carcass traits, and notably affected oxidative stress indices, as well as intestinal pH and histomorphology in the birds. Additionally, the administered probiotics led to increased weight of lymphoid organs, enhanced body weight gain, and improved intestinal histomorphology. Furthermore, the probiotics decreased malondialdehyde and increased total antioxidant capacity in broilers. In conclusion, Bacillus and Lactobacillus probiotics, as single or multi-species, particularly Lactobacillus and combined probiotic, demonstrated potential in alleviating the adverse effects of heat stress in broiler chickens. They could serve as beneficial feed additives and growth enhancers.

Optimization of Liquid Fermentation of Acanthopanax senticosus Leaves and Its Non-Targeted Metabolomics Analysis

To enhance the nutritional value of Acanthopanax senticosus leaves (AL), a fermentation process was conducted using a probiotic Bacillus mixture, and the changes in chemical constituents and biological activities before and after fermentation were compared. A response surface methodology was employed to optimize the liquid fermentation conditions of AL based on their influence on polyphenol content. Non-targeted metabolomics analysis was performed using LC-MS/MS to reveal the differing profiles of compounds before and after fermentation. The results indicated that Bacillus subtilis LK and Bacillus amyloliquefaciens M2 significantly influenced polyphenol content during fermentation. The optimal fermentation conditions were determined to be a fermentation time of 54 h, a temperature of 39.6 °C, and an inoculum size of 2.5% (v/v). In comparison to unfermented AL, the total polyphenol and flavonoid contents, as well as the free radical scavenging capacities measured by DPPH and ABTS assays, and the activities of β-glucosidase and endo-glucanase, were significantly increased. The non-targeted metabolomics analysis identified 1348 metabolites, of which 829 were classified as differential metabolites. A correlation analysis between the differential metabolites of polyphenols, flavonoids, and antioxidant activity revealed that 13 differential metabolites were positively correlated with antioxidant activity. Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of the differential metabolites identified 82 pathways, with two of the top 25 metabolic pathways related to flavonoids. This study explores the potential for enhancing the active ingredients and biological effects of AL through probiotic fermentation using Bacillus strains.

Effects of a potential host gut-derived probiotic, Bacillus amyloliquefaciens AV5, on the growth, biochemical and metabolic responses, and disease resistance of Nile tilapia (Oreochromis niloticus)

The influence of the dietary probiotic Bacillus amyloliquefaciens AV5 on the growth, biochemical and metabolic responses, and disease resistance of Nile tilapia (Oreochromis niloticus) was evaluated. The commercial diet (GC), a diet containing 106 and 108 CFU/g of B. amyloliquefaciens AV5, denoted as G1 and G2, respectively, was fed for 30 days. Fish were allocated to 9 plastic tanks, and each diet was randomly assigned to triplicate groups of 40 fish (22.4 ± 1.3 g).After 30 days of the feeding trial, the specific growth rate, weight gain rate, and final weight increased significantly in G2 compared to those in GC and G1. Feed conversion ratio was significantly higher in the fish-fed GC group than in the G2 group. However, the survival rate of the fish ranged from 99.13 % to 97.17 %, with no significant difference. Glucose levels did not differ significantly (P < 0.05). Total antioxidant capacity (T-AOC), (superoxide dismutase (SOD), and catalase (CAT), as well as digestive enzymes (trypsin, lipase, and protease), were significantly increased in the G2 group relative to the GC and G1 groups.Significantly lower ALT, AST, CHO, TG, and MDA activities were observed in the G2 group than in the GC group. To evaluate the metabolomic response, PCA, OPLS-DA, and volcano plots revealed a distinct difference between the G2 and GC diets, suggesting that the G2 diet impacted the hepatopancreas of fish. Furthermore, challenge experiments revealed that fish fed B. amyloliquefaciens AV5 exhibited substantially increased resistance (P < 0.05) to S. agalactiae at a concentration of 1x108CFU/g. Therefore, dietary supplementation with B. amyloliquefaciens AV5 enhanced the growth performance, metabolic activity, and disease resistance of O. niloticus.

Safety Evaluation and antioxidant potential of new probiotic strain Bacillus subtilis (NMCC-path-14) in Balb/c mice by sub-acute repeated dose toxicity

Probiotics have recently gained significant interest for their possible therapeutic effects in treating numerous health conditions. Probiotics containing Bacillus subtilis have been shown to have several health benefits, most notably in preventing diarrhea and gastrointestinal problems. A novel probiotic strain, Bacillus subtilis (NMCC-path-14), isolated from the rumen of a Nilli Ravi Buffalo, was evaluated for 28-day repeated dose toxicity in Balb/c mice. The NMCC-path-14 in low dose (1 × 108 CFU/ml) and high dose (1 × 1010 CFU/ml) was administered to the mice through gavage regularly. After 28 days of treatment, it was discovered that the no-observed-adverse-effect level (NOAEL) for NMCC-path-14 wasgreater than 1 × 1010 CFU/animal/day. This study also revealed no treatment-related changes in clinical parameters, body weight, gross pathology, or histology. Food consumption, hemoglobin, hematocrit, red blood cell counts, and colon length increased, while total/differential leukocyte count and platelets remained unchanged. The administration of NMCC-path-14 also resulted in decreased bilirubin and creatinine levels. Furthermore, NMCC-path-14 also displayed a promising antioxidant potential by increasing the antioxidant enzymes (GST, GSH, and CAT) and decreasing oxidant enzyme (MDA and NO) levels in vital organs like the liver, kidneys, spleen, and colon. TheNMCC-path-14also decreased the pathogenic bacterial population while increasing the beneficial population. Given the lack of adverse effects observed after NMCC-path-14 treatment, this strain is safe and must be considered as a potential probiotic in humans.

A superior chitin product: Black soldier fly larvae chitin, beneficial to growth performance, muscle quality and health status of largemouth bass Micropterus salmoides, in comparison to shrimp chitin

We appraised the effects of black soldier fly larvae chitin (BSFC) with four levels (0.4 %, 0.8 %, 1.2 % and 1.6 %) and shrimp chitin (SC) with three levels (0.4 %, 0.8 % and 1.6 %) in diets on the growth performance, nutrient composition and health status of largemouth bass (8.00 ± 0.29 g) fed for 56 days. The results showed that the dietary 0.4 % BSFC distinctly increased the specific growth rate and weight gain rate of fish (P < 0.05), and evidently promoted the deposition of C22:1n-9, C24:1n-9 and increased total monounsaturated fatty acid content in the muscle (P < 0.05). BSFC and SC distinctly stimulated the secretion of β-N-acetylglucosaminidase in the hindgut (P < 0.05). The antioxidant status of fish was improved by BSFC and SC, which was attributed to the decreased malonaldehyde contents in the muscle and midgut and the increased total superoxide dismutase and catalase activities in the midgut. The 1.2 %–1.6 % BSFC and 0.8 %–1.6 % SC enhanced the non-specific immunity of fish, which was attributed to the marked promotion of lysozyme, acid phosphatase and alkaline phosphatase activities by BSFC and the distinct enhancement of lysozyme activity by SC in the serum or midgut (P < 0.05). BSFC and SC notably reduced the abundance of potential pathogenic bacterium Vibrio and Photobacterium (P < 0.05), and 0.4 %, 1.2 %, 1.6 % BSFC and 0.4 % SC markedly increased the abundance of probiotic bacterium Cetobacterium (P < 0.05), and the BSFC and SC of 0.8 % significantly increased the abundance of the probiotics Bifidobacterium and Bacillus respectively (P < 0.05). The increase of acetic acid, propionic acid, butyric acid and valeric acid concentrations in the hindgut might be related to the increase of intestinal probiotics, and 0.8 %–1.6 % BSFC and 0.4 % SC obviously increased the total short-chain fatty acid levels in the hindgut (P < 0.05). BSFC and SC remarkably reduced muscle fiber area and diameter (P < 0.05), while fiber densities were significantly increased under 0.4 %, 0.8 % BSFC and 0.4 % SC supplementation (P < 0.05), which was accordant with increased mRNA expression levels of myod, myf-5, smad-2, tgf-β1 and decreased mRNA expression levels of myos in the muscle. Collectively, BSFC and SC had no negative effect on the growth of largemouth bass, and improved the health status of fish. The dietary 0.4 % BSFC supplementation was beneficial to fish growth and muscle quality, and BSFC was a superior chitin product in comparison to SC.

Characterization of probiotic strains of Bacillus sp. from fermented palm wine (Nypa fructicans sp.) and exploration of cellulolytic potential for use as an addition in animal feed.

The main objective of this study was to assess cellulolytic probiotic strains from traditional fermented beverages such as palm wine in order to supplement the animal feed and strengthen the gut health of the animal for better digestibility and absorption. In the present study, different types of microbes were isolated from traditionally prepared palm wine and analyzed for their probiotic nature. For any microbe to be probiotic in nature, it has to sustain the harsh conditions of the human gastrointestinal tract such as acid tolerance, bile tolerance at the lower range of pH, and other properties like auto aggregation test, cell surface hydrophobicity test with non-polar hydrocarbons for evaluating its capabilities to adhere to the intestinal cells and antimicrobial nature against pathogens. Bacillus mycoides strain PR04 and Bacillus subtilis strain PR21 were found to be resistant to acid and bile in simulated artificial gastrointestinal tract model, found to be than 55% hydrophobic with xylene and n-hexadecane and also showed antimicrobial activity greater towards pathogenic strains like Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, and Salmonella typhimurium respectively. The cellulolytic activity of the isolates PR04 and PR21 was evaluated in (0.2-2) % CMC (carboxymethyl cellulose) plate. Bacillus mycoides PR04 and Bacillus subtilis PR21 could degrade carboxymethyl cellulose, filter paper, and sugarcane bagasse. The degradation of sugarcane bagasse was confirmed by Scanning electron microscopy and filter paper degradation after 4days of incubation at 37°C. Cellulase gene of the identified Bacillus sp. strains was amplified by primers CF5'-ACAGGATCCGATGAAAACGGTCAATTTCTATTTT-3' and CR5'-ACTCTCGAGATTGGGTTCTGTTCCCAAT-3'. This study proposes potential probiotic Bacillus mycoides PR04 (Accession no. OR625070) and Bacillus subtilis PR21 (Accession no. OR625072) in the application as an animal feed additive to assist in its digestibility and encourage the gut health.

Probiotic Bacillus subtilis QST713 improved growth performance and enhanced the intestinal health of yellow-feather broilers challenged with coccidia and Clostridium perfringens

In this study, we investigated the effects of dietary supplementation with Bacillus subtilis (QST713) on the performance and intestinal health of yellow feather broilers under Coccidia and Clostridium perfringens (CP) challenge or CP alone. One-day-old yellow-feathered broiler roosters (n = 600) were randomly assigned to 5 groups (6 replicates with 20 roosters per replicate): the Con blank group, the CIC.p group (d24 Coccidia+d28-30 of CP challenge), the CIC.p + BS group (CIC.p +100 mg/kg B. subtilis), the C.p group (d 28-34 of CP challenge), and the C.p +BS group (C.p +100 mg/kg B. subtilis). The experiment lasted 80 d. The birds were evaluated for parameters such as average daily gain (ADG), average daily feed intake (ADFI), feed efficiency (F/G), intestinal lesion score, villus histomorphometry, intestinal tight junctions, inflammatory factors, and cecal microorganisms. The results revealed that 1) C.p. increased the F/G of broilers from 22 to 42 d (P < 0.05), whereas CIC.p. significantly decreased the 42 d and 80 d body weights (BW) and 22-42 d and 1-80 d ADG (P < 0.05) and significantly increased the 22 to 42 d and 1 to 80 d F/G (P < 0.05). The number of intestinal lesions significantly increased at 35 d and 42 d (P < 0.05). CIC.p significantly decreased the jejunum and ileum villus height (VH) and the ileum villus height/crypt depth (P < 0.05) at 35 d. The challenge significantly upregulated the expression of Claudin-1 and IL-4 mRNAs in the jejunum at 35 d and significantly downregulated the expression of IL-10 mRNA in the ileum at 35 d (P < 0.05); the number of unique OTUs in the challenge group decreased significantly after challenge treatment, and the relative abundances of Romboutsia at 35 d and Cladomyces and Lactobacillus at 42 d decreased significantly (P < 0.05). 2) Compared with the challenge groups, the addition of BS decreased the F/G of broilers from 22 to 42 d. Compared with the CIC group, the addition of BS significantly increased the F/G of broilers from 22 to 42 d. Compared with that in the CIC.p group, the addition of BS significantly increased the VH in the jejunum and ileum at 35 d (P < 0.05). Compared with the challenge groups, the BS groups presented significantly lower mRNA expression levels of Claudin-1 (P < 0.05) in the jejunum at 35 d. The Shannon and Chao indices suggested that BS increased the alpha diversity of cecum microorganisms in broilers. Dietary supplementation with B. subtilis can alleviate the damage to intestinal morphology and intestinal barrier function, as well as the altered cecal flora structure in broilers caused by Coccidia and C. perfringens infections.

Evaluation of the potential probiotic Bacillus subtilis isolated from darkbarbel catfish (Pelteobagrus fulvidraco) on growth performance, serum immunity, and disease resistance of Aeromonas hydrophila.

This study aimed to identify potential probiotic strains of Bacillus subtilis from healthy fish gut microbiota for application in aquaculture. The effects of dietary B. subtilis administration on growth performance, serum enzyme activity, immune gene expression, and disease resistance in darkbarbel catfish (Pelteobagrus fulvidraco) were investigated. The isolate, identified through gene sequencing and biochemical tests, demonstrated resilience to pH 3.0% and 6.0% bile, and exhibited extracellular protease, cellulose, lipase, and amylase production. Darkbarbel catfish were fed diets with varying B. subtilis concentrations (0 CFU/kg [T0], 107 CFU/kg [T1], 108 CFU/kg [T2], and 109 CFU/kg [T3]). After 8 weeks, significant increases (p < 0.05) were observed in final body weight, weight gain rate, specific growth rate, serum lysozyme, serum superoxide dismutase, alkaline phosphatase, and total antioxidant capacity, whereas malondialdehyde levels significantly decreased. Feeding darkbarbel catfish with B. subtilis diets increased immunoglobulin M (IgM) and C3 gene expression (p < 0.05), indicating a positive impact on the fish's immune system. The strain upregulated interleukin 10 (IL-10) and transforming growth factor-β (TGF-β) expression and downregulated TNF-α and IL-1β, suggesting potential anti-inflammatory effects. Following a 7-day challenge with Aeromonas hydrophila, fish fed with B. subtilis exhibited lower mortality, with higher survival rates in the T2 and T3 groups. In conclusion, supplementing darkbarbel catfish diets with B. subtilis effectively enhances growth performance, immune response, and disease resistance.

Effects of dietary administration of probiotic (Bacillus subtilis) and iron oxide nanoparticles on the growth parameters of the fish Labeo rohita

Effects of dietary administration of probiotic (Bacillus subtilis) and iron oxide nanoparticles on the growth parameters of the fish Labeo rohita

Bacillus subtilis ZB423: 90-Day repeat dose oral (gavage) toxicity study in Wistar rats.

The novel genetically modified probiotic Bacillus subtilis ZB423 was assessed in a 90-day repeated-dose oral toxicity study adhering to Good Laboratory Practice (GLP) and Organization for Economic Cooperation and Development (OECD) guidelines. Spray-dried spores at a concentration of 1.1E12 CFU/g were administered at doses of 130, 260, and 519 mg/kg body weight/day correlating to 1.43 × 1011, 2.86 × 1011, and 5.71 × 1011 CFU/kg/day, respectively, by oral gavage to Wistar rats for a period of 90 consecutive days. Results showed no toxicologically relevant findings for B. subtilis ZB423 from measured parameters. The no observed adverse effect level (NOAEL) of B. subtilis ZB423 is 519 mg/kg body weight/day corresponding to 5.71 × 1011 CFU/kg/day for lyophilized B. subtilis ZB423 spores under the test conditions employed.

Preventive and reparative potentials of heat-inactivated and viable commensal Bacillus pumilus SE5 in ameliorating the adverse impacts of high soybean meal in grouper (Epinephelus coioides)

Probiotic Bacillus pumilus SE5, heat-inactivated (HSE5) or active (ASE5), were supplemented to high soybean meal (HSM) (36 %) diet at whole term (0–56 days) and middle term (29–56 days) to investigate the preventing and repairing effects of B. pumilus SE5 in ameliorating the adverse effects of HSM in Epinephelus coioides. The results suggested that the HSM significantly decreased the weight gain rate (WGR), specific growth rate (SGR), and increased the feed conversion rate (FCR) at day 56 (P < 0.05), while HSE5 and ASE5 promoted the growth performance. The HSE5 and ASE5 showed preventive and reparative functions on the antioxidant capacity and serum immunity, with significantly increased the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GSH-PX) activities, and reduced malondialdehyde (MDA) level, and increased acid phosphatase (ACP), alkaline phosphatase (AKP), immunoglobulin M (IgM) and complement 3 (C3). The HSM impaired the intestinal health (destroyed the intestinal structure, significantly increased the contents of serum D-lactic acid and diamine oxidase, and reduced the expressions of claudin-3 and occludin), while HSE5 and ASE5 improved them at whole term and middle term. The HSM impaired the intestinal microbiota and reduced its diversity, and the HSE5 or ASE5 improved the intestinal microbiota (especially at whole term). HSE5 and ASE5 improved the intestinal mRNA expressions of anti-inflammatory genes (il-10 and tgf-β1) and reduced the expressions of pro-inflammatory genes (il-1β, il-8, il-12), and promoted the expressions of humoral immune factor-related genes (cd4, igm, mhcII-α) and antimicrobial peptide genes (β-defensin, epinecidin-1 and hepcidin-1), and decreased the expressions of NF-κB/MAPK signaling pathway-related genes (ikk-α, nf-κb, erk-1), and improved the expressions of MAPK signaling pathway-related gene p38-α (P < 0.05). In conclusion, the heat-inactivated and active B. pumilus SE5 effectively prevented and repaired the suppressive effects of soybean meal in E. coioides, which underscored the potential of B. pumilus SE5 as a nutritional intervention agent in HSM diet in aquaculture.

The probiotic strain Bacillus subtilis CU1 primes antimicrobial innate immune response and reduces low-grade inflammation: a clinical study.

LifeinU™ Bacillus subtilis CU1 (BSCU1) has been previously shown to be effective in stimulating mucosal immune responses and supporting resistance to common infectious disease episodes in the elderly. The current clinical study aimed at exploring potential pathways by which BSCU1 could beneficially modulate the immune system and contribute to protection against infection in the general population. A total of 88 participants from three different age groups were supplemented with BSCU1 (2× 109 cfu/day) for 4 weeks. The effect of the intervention on mucosal immunity was assessed by faecal sIgA levels. In addition, a series of complementary immunoassays were selected, including immune phenotyping, gene expression, basal cytokine levels, cytokine levels in lipopolysaccharide (LPS)-stimulated whole blood and phagocytosis assay. Although no significant effect was observed on faecal sIgA levels after intervention, BSCU1 showed a positive effect on a consistent set of markers of the peripheral innate immune system in adults and the elderly. Percentages of peripheral blood myeloid cells as well as the expression of the activation marker CD69 on monocytes were significantly increased after probiotic intervention. BSCU1 supplementation resulted in significant enrichment of clusters of genes involved in response to type I interferon and phagocytosis pathway. Consistently, ex vivo stimulation of whole blood with LPS resulted in a statistically significant increase in pro-inflammatory cytokines (interleukin (IL)-1beta, IL-6, interferon-gamma, IL-12, tumour necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1alpha, IL-8) and phagocytosis assays showed increased capacity of monocytes to engulf bacteria as well as higher phagosome maturation. BSCU1 supplementation also had a positive effect on low-grade inflammation as significant reduction in basal levels of several serum cytokines (IL-10, TNF-alpha, MIP-1alpha, IL-8) were observed in the elderly subgroup. Overall, BSCU1 primed immune cells for a better response to microbial challenges and reduced low-grade inflammation associated with aging. Registered at ClinicalTrials.gov with the identifier NCT05403398.

The Potential of Bacillus Species as Probiotics in the Food Industry: A Review.

The demand for probiotics is increasing, providing opportunities for food and beverage products to incorporate and market these foods as a source of additional benefits. The most commonly used probiotics belong to the genera of Lactobacillus and Bifidobacterium, and traditionally these bacteria have been incorporated into dairy products, where they have a wider history and can readily survive. More recently, there has been a desire to incorporate probiotics into various food products, including baked goods. In recent years, interest in the use of Bacillus species as probiotics has greatly increased. The spores of various Bacillus species such as Bacillus coagulans and Bacillus subtilis, have significantly improved viability and stability under harsher conditions during heat processing. These characteristics make them very valuable as probiotics. In this review, factors that could affect the stability of Bacillus probiotics in food products are highlighted. Additionally, this review features the existing research and food products that use Bacillus probiotics, as well as future research opportunities.

Second-generation snacks prepared from quinoa with probiotic. Physicochemical properties, in vitro digestibility, antioxidant activity and consumer acceptability

Food security is a pressing issue, emphasizing the necessity for food designs that address the current geopolitical and geoeconomic challenges. This study evaluates the impact of including different percentages (10 %, 20 %, 30 %, and 60 %) of high protein quinoa flour (HPQF) in the development of a new rice-based snack. The aim is to create four snack formulations with a protein content enriched with probiotics, surpassing those currently available in the market. Probiotics Bacillus coagulans were added at a 0.1 % concentration. Once the rice flour and quinoa flour are mixed, they are mixed with the probiotic, to move on to the extrusion process. Following the incorporation of probiotics, the snacks were packaged in a modified atmosphere, and their physicochemical properties, Bacillus coagulans probiotic viability, tolerance to artificial gastroenteric juice (TAGJ), starch digestibility, and sensory acceptance were assessed.Significant differences were observed in the expansion index, with the 60 % inclusion snack exhibiting the least expansion. Despite having a higher density, this snack reached a porosity index similar to that of the 20 % HPQF snack. Achieving a 17 % protein content in the snacks was possible with a 60 % inclusion rate. Texture was notably affected by the inclusion of HPQF, with snacks having higher inclusion levels showing increased hardness. Probiotic viability evaluation consistently remained above 106 UFC/g of snack, while TAGJ exhibited a viability of 75 %. Although HPQF inclusion led to a decrease in the glycemic index (GI), snacks still maintained a GI above 70 %. Regarding antioxidant properties, snacks with 60 % HPQF inclusion displayed superior results, reaching 35.29, 5.52, and 13.74 μmol of AA/g, measured via ABTS, DPPH, and FRAP methods, respectively. These findings demonstrate a heightened antioxidant capacity compared to other formulations. Our results indicate that the new probiotic snack serves as a rich source of protein and probiotics and is well-received sensorially. However, it is worth noting that it falls within the category of high GI foods, prompting the need for future studies aimed at reducing this parameter.

The effects of using hydrolyzed feather meal, amino acids, and probiotics in the diet of juvenile rainbow trout on growth, digestibility, and expression of growth-related genes

The study investigated the effect of replacing fishmeal by varying levels of hydrolyzed feather meal (HFM) as well as dietary probiotic supplementation on growth performance, digestibility, histology, and gene expression of juvenile rainbow trout (Oncorhynchus mykiss). Five iso-nitrogenous (average of 50.60% crude protein), iso-energetic (average of 21.79 kJ/g), and iso-lipidic (average of 21.86% crude lipid) diets were formulated and fed to triplicate groups of juvenile rainbow trout weighing 29.65 ± 0.39 g (mean ± SD) for 75 days. Dietary treatments included one control (50% fishmeal) and four experimental diets, each containing 2 g/kg probiotics (Lactobacillus plantarum and Bacillus subtilis). The experimental diets included HFM30 (150 g/kg HFM, 9 g/kg lysine, and 4 g/kg methionine), HFM35 (175 g/kg HFM, 11 g/kg lysine, and 5 g/kg methionine), HFM40 (200 g/kg HFM, 13 g/kg lysine, and 6 g/kg methionine), and HFM45 (225 g/kg HFM, 15 g/kg lysine, and 7 g/kg methionine). Up to 40% replacement of fishmeal with HFM showed no significant difference compared to control group in growth performance (P > 0.05). Feed utilization of HFM45 was slightly lower than control and all the other experimental groups. There was no statistically significant difference in FCR value between HFM40 and control groups (P > 0.05). The apparent digestibility coefficients (ADCs) for protein and amino acids were very high in all groups (P < 0.05). Intestinal mucosa and sub‐mucosa layers of experimental fish showed general tissue integrity with no signs of tissue necrosis. For intestinal morphology, where 45% HFM replacement was applied, villus length to crypt depth (VL to CD) and villus surface area (SA) decreased by 46.01% and 44.44%, respectively, compared to the control group (P < 0.05). This situation shows that intestinal morphology can be damaged when the highest level (HFM45) of feather meal is used. Dietary HFM upregulated growth-related genes such as IGF-II, IGFBP-1b, IGFr1a, GDF9, and FGF2 and downregulated GHR-I and IGF-I. Overall, inclusion of HFM at 40% showed similar results to control group in juvenile rainbow trout feeding.

Growth phase-dependent changes in conformational and physicochemical properties of bacterial surface biopolymers lead to changes in bacterial adhesion strength at nanoscale and macroscale

This study presents a detailed investigation into conformational, physicochemical and adhesive characteristics of biopolymers on the surfaces of Escherichia coli and potential probiotic Bacillus subtilis harvested from middle-exponential phase (mid-EP), late-exponential phase (late-EP) and early-stationary phase (early-SP) of growth. The lengths to which bacterial surface biopolymers extend (biopolymer brush lengths), densities of grafted bacterial surface biopolymers indicating the amounts of molecules covering the bacterial surfaces (biopolymer grafting densities), adhesion forces of bacterial surface biopolymers to the model inert surfaces of silicon nitride (Si3N4), and the pull-off distances of biopolymers from Si3N4 were measured in water by atomic force microscopy (AFM). The Weibull analysis of AFM adhesion data showed that as the culture aged, the adhesive bonds between Si3N4 AFM tips and surface molecules of E. coli harvested from the culture were broken with a higher applied force. However, the highest applied force to break the bonds was required for B. subtilis in late-EP, followed by those required for cells in early-SP and mid-EP, respectively. The results of a steric model fitting to AFM approach force-distance (FD) curves and analysis of the pull-off distances in the AFM retraction FD curves showed higher biopolymer grafting density for E. coli in early-SP and longer biopolymer brush layer for B. subtilis in late-EP, which were associated with stronger adhesion to Si3N4 in water. The results of thermodynamic adhesion energy calculations based on the Wu model showed that polar interaction energy dominated the bacterial adhesion at the macroscale, the strength of which varied as a function of the growth phase for both E. coli and B. subtilis. The growth phase-dependent variation in polar components of thermodynamic adhesion energies between the bacteria and Si3N4 in water was consistent with the growth phase-dependent variation in the bond strengths between the bacteria and Si3N4 in water as revealed by the Weibull analysis of AFM adhesion data. Therefore, information obtained by Weibull analysis of nanoscale AFM bacterial adhesion data can be used to predict macroscale bacterial adhesion to the model inert Si3N4 surface in water.