Evaluation of the probiotic characteristics of Bacillus species isolated from different food sources

The Isolation, Identification, and Whole-Genome Sequencing of a Potential Probiotic, Clostridium butyricum YF1, Isolated from the Intestine of the Ricefield Eel (Monopterus albus)

Clostridium butyricum, recognized as a probiotic, is widely distributed in the intestines of various animals. In this study, the C. butyricum strain YF1 was isolated from the intestine of the ricefield eel (Monopterus albus) using an anaerobic culture method and was identified through morphological, physiological, biochemical, and 16S rRNA sequence analyses. Notably, C. butyricum YF1 exhibited a rapid growth rate and was found to produce ten types of short-chain fatty acids, particularly high-yield acetic acid and butyric acid. Additionally, YF1 demonstrated a high tolerance to elevated temperatures (70 °C), bile salts (0.1% to 0.5%), artificial intestinal fluid, and artificial gastric fluid, while being sensitive to most antibiotics. Further whole-genome sequencing revealed that C. butyricum YF1 has a total genome size of 4,314,266 bp and contains 3853 coding genes. Specifically, 82 tRNAs, 21 rRNAs, 288 repeat sequences, 13 prophages, and two gene islands were detected. Moreover, gene function analysis indicated that the highest number of genes were annotated to metabolic processes, and the butyric acid metabolism pathway was found to be complete. Meanwhile, 598 virulence genes and 186 resistance genes were predicted. In conclusion, the findings from this study contribute to probiotic development and provide innovative approaches for the sustainable and healthy cultivation of ricefield eels.

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.

Two-year investigation of spore-formers through the production chain at two cheese plants in Norway

Spore-forming bacteria are the most complex group of microbes to eliminate from the dairy production line due to their ability to withstand heat treatment usually used in dairy processing. These ubiquitous microorganisms have ample opportunity for multiple points of entry into the milk chain, creating issues for food quality and safety. Certain spore-formers, namely bacilli and clostridia, are more problematic to the dairy industry due to their possible pathogenicity, growth, and production of metabolites and spoilage enzymes. This research investigated the spore-forming population from raw milk reception at two Norwegian dairy plants through the cheesemaking stages until ripening. Samples were collected over two years and examined by amplicon sequencing in a culture independent manner and after an anaerobic spore-former enrichment step. In addition, a total of 608 isolates from the enriched samples were identified at the genus or species level using MALDI-TOF analysis. Most spore-forming isolates belong to the genera Bacillus or Clostridium, with the latter dominating the enriched MPN tubes of raw milk and bactofugate. Results showed a great variation among the clostridia and bacilli detected in the enriched MPN tubes. However, B. licheniformis and C. tyrobutyricum were identified in all sample types from both plants throughout the 2-year study. In conclusion, our results shed light on the fate of different spore-formers at different processing stages in the cheese production chain, which could facilitate targeted actions to reduce quality problems.

Study of the probiotic properties of Lacticaseibacillus casei subsp. casei NCIM 5752 and the optimization of whey-based media for the production of its biomass using response surface methodology

In this study, Lacticaseibacillus casei NCIM 5752, a new isolate has been explored for probiotic properties and has shown significant bile salt hydrolase activity and cholesterol-reducing activity (56.7 ± 0.27%) in the presence of bile salts. It also tested negative for the production of lecithinase and gelatinase, indicating its non-pathogenic nature. The test strain was able to tolerate pH of 2.0 and 3.0 with 63.42 and 94.7% of the cells survived after 3 h. L. casei showed auto-aggregation of 85.3% and surface hydrophobicity of 22.5% in xylene and 19.4% in hexane. Paneer whey was explored as a basic raw material for alternative media formulation for growing lactic acid bacteria. Paneer whey was found to contain lactose (4.15%), protein (0.42%), and rich in mineral content. Response surface methodology was employed to optimize the medium composition with three independent variables yeast extract (X1), dextrose (X2), and dipotassium hydrogen phosphate (X3), and the response-Y was set to biomass obtained in terms of log CFU/ml. They were supplemented to paneer whey medium for growing this strain. The second-order polynomial regression model predicted that the maximum cell mass production of 11.30 ± 0.5 log CFU/ml at optimal composition of 16.22 g/L of yeast extract, 19.31 g/L of dextrose, and 2.12 g/L of dipotassium hydrogen phosphate in paneer whey medium. Experiments were conducted to validate the RSM results, and the biomass achieved was 11.27 ± 0.50 log CFU/ml, which is in close agreement with the yield predicted by the RSM. By applying the fermentation strategy, the biomass was increased to 5.56 ± 0.34 g/L dry cell weight corresponding to 11.58 ± 0.24 log CFU/ml. The newly optimized media was significantly cost-effective and produced 26.45% more biomass than the conventional MRS media. This optimized media may find application for the large-scale biomass production of probiotics.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03899-z.

Isolation and characterization of novel Bacillus strains with superior probiotic potential: comparative analysis and safety evaluation

Despite the current use of some Bacillus spp. as probiotics, looking for and introducing new efficient and safe potential probiotic strains is one of the most important topics in both microbiology and food industry. This study aimed to isolate, identify, and evaluate the probiotic characteristics and safety of some Bacillus spp. from natural sources. Thirty-six spore-forming, Gram-positive, and catalase-positive Bacillus isolates were identified in 54 samples of soil, feces and dairy products. Bacterial identification was performed using 16S rDNA sequencing. To evaluate the probiotic potential of isolates, the resistance of bacterial cells to simulated gastrointestinal tract (GIT) conditions, the presence of enterotoxin genes, their susceptibility to antibiotics, antimicrobial and hemolytic activities and biochemical profiles were investigated. The results revealed that eight sporulating Bacillus spp. isolates fulfilled all tested probiotic criteria. They showed a high growth rate, non-hemolytic and lecithinase activity, and resistance to simulated GIT conditions. These strains exhibited broad-spectrum antibacterial activity against pathogenic bacteria. In addition, they did not exhibit antibacterial resistance to the 12 tested antibiotics. The results of this study suggest that these isolates can be considered as candidates for functional foods and as safe additives to improve diet quality.

In-silico analysis of probiotic attributes and safety assessment of probiotic strain Bacillus coagulans BCP92 for human application

The whole genome sequence (WGS) of Bacillus coagulans BCP92 is reported along with its genomic analysis of probiotics and safety features. The identification of bacterial strain was carried out using the 16S rDNA sequencing method. Furthermore, gene-related probiotic features, safety assessment (by in vitro and in silico), and genome stability were also studied using the WGS analysis for the possible use of the bacterial strain as a probiotic. From the BLAST analysis, bacterial strain was identified as Bacillus (Heyndrickxia) coagulans. WGS analysis indicated that the genome consists of a 3 475 658 bp and a GC-content of 46.35%. Genome mining of BCP92 revealed that the strain is consist of coding sequences for d-lactate dehydrogenase and l-lactate dehydrogenases, 36 genes involved in fermentation activities, 29 stress-responsive as well as many adhesions related genes. The genome, also possessing genes, is encoded for the synthesis of novel circular bacteriocin. Using an in-silico approach for the bacterial genome study, it was possible to determine that the Bacillus (Heyndrickxia) coagulans strain BCP92 contains genes that are encoded for the probiotic abilities and did not harbour genes that are risk associated, thus confirming the strain's safety and suitability as a probiotic to be used for human application.

Probiotic Properties and Anti-inflammatory Activity of Bacillus spp. Isolated from Ethnically Fermented Soybean

Bacillus spp. probiotics used as feed additives can form spores and tolerate the harsh conditions of the human digestive system and are beneficial for the treatment of inflammatory bowel syndrome. Since reports on probiotics and anti-inflammatory properties of Bacillus spp. isolated from the fermented food of Northeast India have not been explored much. The present study focused on Bacillus spp. BN5, AY5, and AN8, possessing these desired properties. In the probiotics study, the isolates were screened for their tolerance to acid and bile salt, auto-aggregation, hydrophobicity, cholesterol assimilation, antibiotic resistance, and antagonistic properties. It was found that these isolates possessed the desirable probiotic traits. The Bacillus spp. culture and their supernatant were also screened for their ability to reduce LPS-induced inflammation in murine macrophage (RAW 264.7) cells. All the Bacillus spp. culture and their supernatant treatments were found to reduced the Nitric oxide (NO) production by LPS-induced cell lines. The supernatant of LPS-induced cell lines were also analyzed to measure the level of inflammatory cytokine production. It was found that the levels of TNF-α, IL-6, and IL-1β were reduced after co-treatment with LPS and Bacillus spp. culture or LPS and Bacillus spp. supernatant. Results suggested that the Bacillus spp. are potential probiotic candidates with anti-inflammatory properties.

Bacillus Strains Isolated from Korean Fermented Food Products with Antimicrobial Activity Against Staphylococci, an Alternative for Control of Antibiotic-Resistant Pathogens

Multidrug resistance in foodborne and clinical pathogens is a worldwide health problem. The urgent need for new alternatives to the existing antibiotics is emerging. Bacteriocin-like inhibitory substances can be considered part of the new generation of antimicrobials, which can be potentially applied in the food industry and health care practices. This study aimed to select Bacillus strains with antimicrobial activity against Staphylococcus spp. with future application in the formulation of pharmaceutical antimicrobial preparations. Putative antimicrobial agent-producing strains, previously isolated and preidentified as Bacillus spp. were profiled by repetitive element sequence-based polymerase chain reaction (rep-PCR) and 16s rRNA sequencing identified the strains as Bacillus tequilensis ST1962CD with 99.47% identity confidence and as Bacillus subtilis subsp. stercoris ST2056CD with 98.45% identity confidence. Both the selected Bacillus strains were evaluated via biomolecular and physiological approaches related to their safety and virulence, beneficial properties, enzyme production profile, and presence of corresponding genes for the production of antimicrobials and virulence. Both strains were confirmed to harbor srfa and sbo genes and be free of hemolysin binding component (B) and two lytic components (L1 and L2) [BL] and nonhemolytic enterotoxin-associated genes. Produced antimicrobial agents by strains ST1962CD and ST2056CD were partially purified through the combination of ammonium sulfate precipitation and hydrophobic-based chromatography on SepPakC18 and evaluated regarding their cytotoxicity. The dynamics of bacterial growth, pH change, accumulation of produced antimicrobials, and the mode of action were evaluated. Obtained results were pointing to the potential application of safe B. tequilensis ST1962CD and B. subtilis subsp. stercoris ST2056CD strains as functional beneficial microbial cultures that are putative producers of surfactin and/or subtilosin, as potent antimicrobials, for the treatment of some staphylococcal-associated infections. Expressed antimicrobials were shown to be not cytotoxic, and appropriate biotechnological approaches need to be developed for cost-effective production, isolation, and purification of expressed antimicrobials by studied strains.

The isolation, identification, whole-genome sequencing of Clostridium butyricum LV1 and its effects on growth performance, immune response, and disease-resistance of Litopenaeus vannamei

In this study, a strain of Clostridium butyricum was isolated from the intestine of Litopenaeus vannamei with the method of anaerobic microbial isolation and culture. Next, the probiotic properties of LV1 were evaluated with susceptibility tests, tolerance tests, and whole genome sequencing in vivo and in vitro, followed by the analysis of the effect of LV1 on the growth performance, immune response, and disease resistance of Litopenaeus vannamei. According to the results, the 16 S rDNA sequence of LV1 was 100% homolofgous to the reference sequence of Clostridium butyricum. Moreover, LV1 was resistant to several antibiotics including amikacin, streptomycin, and gentamicin and highly tolerated artificial gastric and artificial intestinal fluids. The whole genome of LV1 was 4625,068 bp in size and included 4336 coding genes. Among these genes, GO, KEGG, and COG databases exhibited the highest number of genes annotated to metabolic pathway classes and 105 genes annotated as glycoside hydrolases. Meanwhile, 176 virulence genes were predicted. The use of diets supplemented with 1.2 × 10⁹ CFU/kg of LV1 live cells significantly increased the weight gain and specific growth rates of Litopenaeus vannamei and the activity of serum superoxide dismutase, glutathione peroxidase, acid phosphatase, and alkaline phosphatase (P < 0.05). Meanwhile, the use of these diets markedly improved the relative expression of intestinal immunity- and growth-related genes. In conclusion, LV1 has excellent probiotic properties. Specifically, the addition of 1.2 × 10⁹ CFU/kg of LV1 live cells to the diet improved the growth performance, immune response, and disease-resistance of Litopenaeus vannamei.

Intestinal Dysbiosis in Rats: Interaction between Amoxicillin and Probiotics, a Histological and Immunohistochemical Evaluation

Gastrointestinal microbiota can be easily altered by common treatments, such as antibiotic therapy. However, the dysmicrobism induced by such a treatment may be counteracted by the administration of different beneficial microbes, such as probiotics. Therefore, this study aimed to establish the interaction between intestinal microbiota, antibiotic therapy, and sporulated bacteria, correlated with the evolution of growth indices. Twenty-five Wistar rats, females, were divided into five groups. Amoxicillin and a probiotic combination of Bacillus subtilis, Bacillus licheniformis, and Pediococcus acidilactici were administered according to each group's purpose. The conventional growth indices were calculated and histological and immunohistochemical assessments were realized from intestinal samples. The results of the conventional growth indices suggested a beneficial effect when the antibiotic therapy was accompanied by probiotics, while for the groups where the dysmicrobism was present, the values for feed conversion ratio were negative. These findings were supported by the microscopic aspects of the intestinal mucosa, which suggested a decreased absorption capacity due to significant morphological changes. Moreover, the immunohistochemical reaction of the inflammatory cells from intestinal lamina propria was intensely positive for the same affected groups. However, for the control group and the group with antibiotic and probiotic treatment, the immunopositivity was significantly decreased. Probiotics based on bacillus spores administered simultaneously with the antibiotic offered the best restoration of the gut microbiota, a fact suggested by the absence of intestinal lesions, a normal food conversion ratio, and low expression of TLR4 and LBP immunomarkers.

Identification of Lactobacillus strains from human mother milk and cottage cheese revealed potential probiotic properties with enzymatic activity

The main attempt of this study is to isolate, determine potential probiotic properties and enzyme production of some lactic acid bacteria (LAB). Among all isolates, two LAB strains isolated from human mother milk and cottage cheese revealed antimicrobial activity against some tested pathogenic strains. Both isolates inhibited all the tested pathogens except Escherichia coli. The two isolates were identified by morphological, biochemical properties and then by 16S rRNA gene sequencing technique as Lactobacillus acidophilus SAM1 and Lactiplantibacillus plantarum SAM2. Potential probiotic characters were investigated. Both strains survived in relatively low pH and high bile concentrations and were able to grow at 0.5% of pancreatin concentrations. Their growth decreased by increasing phenol from 0.2% till 0.5%. Both strains did not show hemolytic activity. Coaggregation potential was exhibited by the two strains against Staphylococcus aureus and Candida albicans. Hydrophobicity of Lactobacillus acidophilus SAM1 and Lactiplantibacillus plantarum SAM2, with ethyl acetate; were 88.1% and 82.8%, respectively. Lactobacillus acidophilus SAM1 was susceptible to Ampicillin, Penicillin, Erythromycin, Ciprofloxacin and Tetracycline; on the contrary, it resists Vancomycin and Cefoxitin; while Lactiplantibacillus plantarum SAM2 resists all tested antibiotics. Maximum growth was achieved using glucose as a carbon source and yeast extract as nitrogen source for both strains; however, glucose is the most preferred carbon source for microorganisms and it prevents the uptake of carbon from other sources like yeast by catabolite repression mechanism. Lactobacillus acidophilus SAM1 produces lipase enzyme, while Lactiplantibacillus plantarum SAM2 produces amylase and protease.

Priestia flexa KS1: A new bacterial strain isolated from human faeces implicated in mucin degradation

The human gut acts as a habitat for diverse microbial communities, including mucin utilizers that play a significant role in host health and diseases. In this study, a gram-positive, rod-shaped mucin degrading bacterium was isolated from human faeces that belonged to the Priestia flexa species. Priestia isolate was analyzed for mucin-degrading ability and found that the KS1 strain could grow on mucin as the sole carbon source. The experimental results of the mucolytic zone around the colony and a 58% decrease in carbohydrate concentration confirmed the ability of Priestia to degrade mucin. The intracellular and extracellular glycosidase assay data supported the above results suggesting the ability of P. flexa to produce glycan hydrolysis enzymes that convert complex mucin oligosaccharide chains into simple glycans. The survival ability of the KS1 strain in simulated gastrointestinal conditions revealed that it could tolerate low pH (≥ 50% cell viability at pH 1.0) and 0.5% bile salt concentration (≥ 85% cell viability). The strain showed low hydrophobicity towards n-hexadecane (26.51 ± 0.92%) and xylene (21.71 ± 0.54%). Moreover, the KS1 culture was resistant to cefixime, clavulanic acid/ceftazidime, nafallin, methicillin, trimethoprim, kanamycin, and nalidixic antibiotic. Our results highlight the isolation of P. flexa KS1 strain that degrade mucin under in vitro conditions and show its better acclimatization within the GI environment. Further studies are required to unearth the molecular mechanisms involved in the degradation of mucin oligosaccharides in the human gut, advancing our understanding of health and disease.

Screening of Spore-Forming Bacteria with Probiotic Potential in Pristine Algerian Caves

The interest and exploration of biodiversity in subsurface ecosystems have increased significantly during the last 2 decades. The aim of this study was to investigate the in vitro probiotic properties of spore-forming bacteria isolated from deep caves. Two hundred fifty spore-forming microbes were enriched from sediment samples from 10 different pristine caves in Algeria at different depths. Isolates showing nonpathogenic profiles were screened for their potential to produce digestive enzymes (gliadinase and beta-galactosidase) in solid and liquid media, respectively. Different probiotic potentialities were studied, including (i) growth at 37°C, (ii) survival in simulated gastric juice, (iii) survival in simulated intestinal fluid, and (iv) antibiotic sensitivity and cell surface properties. The results showed that out of 250 isolates, 13 isolates demonstrated nonpathogenic character, probiotic potentialities, and ability to hydrolyze gliadin and lactose in solution. These findings suggest that a selection of cave microbes might serve as a source of interesting candidates for probiotics.

IMPORTANCE Previous microbial studies of subsurface ecosystems like caves focused mainly on the natural biodiversity in these systems. So far, only a few studies focused on the biotechnological potential of microbes in these systems, focusing in particular on their antibacterial potential, antibiotic production, and, to some extent, enzymatic potential. This study explores whether subsurface ecosystems can serve as an alternative source for microbes relevant to probiotics. The research focused on the ability of cave microbes to degrade two substrates (lactose and gliadin) that cause common digestive disorders. Since these enzymes may prove to be useful in food processing and in reducing the effect of lactose and gliadin digestion within intolerant patients, isolation of microbes such as in this study may expand the possibilities of developing alternative strategies to deal with these intolerances.

Assessment of probiotic and technological properties of Bacillus spp. isolated from Burkinabe Soumbala

BACKGROUND

Soumbala is a highly loved alkaline traditional fermented food condiment in Burkina Faso. It harbors various microbiota dominated by fermentative Bacillus spp. as functional microorganism with little confirmed health-promoting properties.

METHODS

The present study aimed to evaluate six Bacillus strains previously isolated and identified from soumbala. These strains were selected as presumptively safe bacteria for probiotic and technological characteristics. These strains were assessed for in vitro probiotic criteria (tolerance to acidic pH, gastric juice, 0.3% (m/v) bile salts, intestinal juice and 0.4% (w/v) phenol, cell surface hydrophobicity, auto-aggregation capacity, antimicrobial activity against foodborne pathogens, antibiotic susceptibility and biofilm production) and technological properties, including protease, amylase, lipase, and tannase activity, as well as poly-γ-glutamic acid (PGA) production and thermo-tolerance.

RESULTS

All tested Bacillus strains (B54, F20, F24, F21, F26 and F44) presented variable relevant probiotic properties (good tolerance to pH 2 and pH 4, gastric juice, bile salts, intestinal juice and phenol), with marked differences in hydrophobicity and auto-aggregation capacity ranging from 73.62-94.71% and 49.35-92.30%, respectively. They exhibited a broad spectrum of activity against foodborne pathogens depending on target pathogen, with the highest activity exhibited by strain F20 (29.52 mm) against B. cereus 39 (p <  0.001). They also showed good biofilm production as well as variable hydrolytic enzyme activities, including protease (43.00-60.67 mm), amylase (22.59-49.55 mm), lipase (20.02-24.57 mm), and tannase (0-10.67 mm). All tested Bacillus strains tolerated temperature up to 50 °C, while only strains F26 and F44 showed the best PGA production.

CONCLUSION

Overall, the tested cultures exhibiting potential probiotic and technological characteristics; particularly B. cereus F20, B. benzoevorans F21, B. cabrialessi F26, and B. tequilensis F44 could be a source of probiotic-starters of commercial interest in the production of high-quality soumbala.

Effect of Bacillus coagulans SNZ 1969 on the Improvement of Bowel Movement in Loperamide-Treated SD Rats

Bacillus coagulans SNZ 1969 (B. coagulans SNZ 1969) is a spore-forming bacterium reported to be effective in attenuating constipation. However, there is no study on whether B. coagulans SNZ 1969 could improve constipation through mucin secretion and changes in intestinal hormones. To address this knowledge gap, rats were orally administrated with various treatments for four weeks. The normal control (NOR) group received saline only. There were four constipation-induced groups. The LOP group received only loperamide (LOP), a constipation-inducing agent. The BIS group received both LOP and Bisacodyl (BIS, a constipation treatment agent). The SNZ-L group received both LOP and B. coagulans SNZ 1969 at 1 × 10⁸ CFU/day. The SNZ-H group received LOP and B.coagulans SNZ 1969 at 1 × 10¹⁰ CFU/day. As indicators of constipation improvement, fecal pellet weight, fecal water content, gastrointestinal transit time, and intestinal motility were measured. Mucus secretion in the colon was determined by histological colon analysis and mucin-related gene expressions. Gastrointestinal (GI) hormones were also measured. SNZ-L and SNZ-H groups showed significantly increased fecal weights, fecal water contents, and intestinal motility than the LOP group. SNZ-L and SNZ-H groups also showed higher secretion of mucin in the colon and mRNA expression levels of Mucin 2 and Aquaporin 8 than the LOP group. The SNZ-H group showed significantly increased substance P but significantly decreased somatostatin and vasoactive intestinal peptide than the LOP group. The results of this study suggest that B. coagulans SNZ 1969 intake could attenuate constipation through mucin secretion and alteration of GI hormones.

Development and Evaluation of a Commercial Direct-Fed Microbial (Zymospore®) on the Fecal Microbiome and Growth Performance of Broiler Chickens under Experimental Challenge Conditions

Simple Summary

Probiotics are recognized for their beneficial health-promoting properties, through competitive exclusion, promoting maintenance of intestinal epithelial integrity and host immune system homeostasis. The use of some spore-forming bacteria from the genus Bacillus has earned interest as a direct-fed microbial in recent years as a potential alternative to antibiotic growth promoters and growth enhancers. The present study evaluates the use of a Bacillus subtilis spore-based direct-fed microbial (Zymospore^®, Vetanco, Villa Martelli, Argentina) compared to an antibiotic growth promoter on the performance of broiler chickens under experimental intestinal challenge conditions. The results suggest that Zymospore^® increases the diversity of the broiler fecal microbiota and is an acceptable substitute for commonly used antibiotic growth promoters under defined and non-defined intestinal dysbiosis conditions.

Abstract

Direct-fed microbials (DFM) are added to broiler chicken diets in order to promote the proliferation of beneficial intestinal bacterial populations, which may lead to gains in performance efficiency and, potentially, reduce the level of enteric pathogens in the broiler chickens. The selection and laboratory evaluation of Bacillus subtilis strains as well as the experimental trial results of a novel Bacillus-based commercial DFM product are described. Fifteen wild-type Bacillus subtilis strains were characterized and assayed for their enzyme production capability, spore resistance to pH, salinity, and temperature, and ability to inhibit the growth of E. coli and Salmonella spp. The final DFM formulation was evaluated and compared to an antibiotic growth promoter (AGPs) in two experimental trials. In Experiment 1, broilers were given a defined challenge of Eimeria spp. and Clostridium perfringens to induce intestinal dysbiosis. The optimal dose of the DFM was determined to be 0.3 kg/ton of feed. At this dose, the broilers fed the DFM performed as well as the Flavomycin^®-fed broilers. Further, intestinal microbiome analysis indicates that the use of the DFM enhances bacterial diversity of the gut flora by day 5 of age, increasing levels of lactic acid bacteria (LAB) and Clostridiales by 25 days of age, which may enhance the digestion of feed and promote growth of the birds. In Experiment 2, the broilers were raised on recycled litter and given an undefined challenge orally to mimic commercial growth conditions. In this trial, the DFM performed as well as the bacitracin methylene disalicylate (BMD)-11%-fed birds. The results of the present studies suggest that this novel DFM, Zymospore^®, improves the performance of broiler chickens under experimental challenge conditions as effective as an AGP, providing a safe and effective substitute to the poultry industry.

Bread as probiotic carriers: Resistance of Bacillus coagulans GBI-30 6086 spores through processing steps

This study evaluated the resistance of Bacillus coagulans GBI-30, 6086 (BC) spores through the processing and storage of white and whole wheat bread. The physicochemical parameters of the probiotic bread formulations were also characterized. Loaves of bread containing or not BC were prepared. Throughout the processing, samples were collected (after mixture, after fermentation, and after baking) for enumeration of BC. In addition, BC was enumerated in different parts of loaves of bread (crust, crumb, and whole slice) collected after baking (day zero) and at different storage times (3, 7, and 10 days). The incorporation of BC did not affect the moisture, specific volume, texture and color parameters, water activity, and pH of loaves of bread. Mixing and fermentation steps did not reduce the BC survival in white or whole wheat bread. The highest (p < 0.05) number of decimal reductions (γ) was caused by baking in the crust for both loaves of bread. Baking caused around two γ of BC in the crust and 1.5 γ of BC in crumb and a whole slice of white and whole bread. Generally, storage did not increase the γ caused by baking, regardless of the evaluated part or type of bread. Results show the impacts of baking on BC and highlight the formulated white and whole wheat loaves of bread as suitable carriers for delivering the probiotic BC.

Effects of Bacillus licheniformis and Bacillus subtilis on Gut Barrier Function, Proinflammatory Response, ROS Production and Pathogen Inhibition Properties in IPEC-J2—Escherichia coli/Salmonella Typhimurium Co-Culture

The emergence of antimicrobial resistance raises serious concerns worldwide. Probiotics offer a promising alternative to enhance growth promotion in farm animals; however, their mode of action still needs to be elucidated. The IPEC-J2 cell line (porcine intestinal epithelial cells) is an appropriate tool to study the effect of probiotics on intestinal epithelial cells. In our experiments, IPEC-J2 cells were challenged by two gastrointestinal (GI) infection causing agents, Escherichia coli (E. coli) or Salmonella enterica ser. Typhimurium (S. Typhimurium). We focused on determining the effect of pre-, co-, and post-treatment with two probiotic candidates, Bacillus licheniformis or Bacillus subtilis, on the barrier function, proinflammatory cytokine (IL-6 and IL-8) response, and intracellular reactive oxygen species (ROS) production of IPEC-J2 cells, in addition to the adhesion inhibition effect. Bacillus licheniformis (B. licheniformis) and Bacillus subtilis (B. subtilis) proved to be anti-inflammatory and had an antioxidant effect under certain treatment combinations, and further effectively inhibited the adhesion of pathogenic bacteria. Interestingly, they had little effect on paracellular permeability. Based on our results, Bacillus licheniformis and Bacillus subtilis are both promising candidates to contribute to the beneficial effects of probiotic multispecies mixtures.

Bacillus toyonensis SAU-19 and SAU-20 Isolated From Ageratina adenophora Alleviates the Intestinal Structure and Integrity Damage Associated With Gut Dysbiosis in Mice Fed High Fat Diet

This study was performed to identify potential probiotic endophytes from Ageratina adenophora and evaluate their ameliorating effects on gut injury and integrity damage associated with microbiota dysbiosis in mice fed high fat diet. Using morphological and biochemical tests, and 16S rRNA gene sequencing technique, two bacteria endophytes were identified as strains of Bacillus toyonensis and were named Bacillus toyonensis SAU-19 (GenBank No. MW287198) and Bacillus toyonensis SAU-20 (GenBank No. MW287199). Sixty (60) mice were divided into five groups, group 1 was the negative control fed normal diet (NS), group 2 was fed High fat diet (HF), Group 3 was fed High fat diet + 106 Lactobacillus rhamnosus (LGG), group 4 was fed High fat + 106 Bacillus toyonensis SAU-19 and group 5 fed High fat diet + 106 Bacillus toyonensis SAU-20. After 35 days, histological and immunohistochemistry examination were performed in the ileum tissues. Furthermore, DAO and antioxidants activities were measured in serum, mRNA expressions of tight junction proteins (occludin and ZO-1) and inflammation related cytokines (IL-1β, TFN-α, IL-2, IL-4, and IL-10) in the ileum tissues as well as sIgA levels and total bacteria (Escherichia coli, Salmonella, Staphylococcus, and Lactobacillus) in the small intestine and cecum content. The results showed an increase in the DAO activity, oxidative stress parameter (MDA), pro-inflammation cytokines (IL-1β, TFN-α, IL-2), reduce immunity (sIgA), and destroyed intestinal structure and integrity (reduce tight junction proteins) in the high fat diet group and this was associated with destruction of the gut microbiota composition (increasing pathogenic bacteria; E. coli, Salmonella, Staphylococcus and reducing beneficial bacteria, Lactobacillus spp.) in mice (P < 0.05). However, the administration of Bacillus toyonensis SAU-19 and SAU-20 reverted these effects. Our findings indicated that, Bacillus toyonensis SAU-19 and SAU-20 isolated from A. adenophora could prevent the excess weight gain from high fat diet feeding, improved antioxidant status and alleviated the intestine integrity damage as well as reduce the population of enteric bacteria such as E. coli, Salmonella, and S. aureus and increasing the population of beneficial bacteria such as Lactobacillus in the gut of mice fed high fat diet, therefore, can serve as a potential probiotics in humans and animals.

In vitro probiotic and safety attributes of Bacillus spp. isolated from beebread, honey samples and digestive tract of honeybees Apis mellifera

Bacillus species isolated from honeybee Apis mellifera gut, honey and bee bread samples were characterized for their in vitro probiotic and safety attributes. Alpha and γ haemolytic cultures were tested for their antibiotic resistance, antibacterial spectrum, acid and bile tolerance, adhesion ability (auto-aggregation, co-aggregation and hydrophobicity) and phenol tolerance. Safety criteria included evaluation of virulence genes and cytotoxicity percentages. Bacillus isolates inhibited both Gram-positive and Gram-negative pathogens including Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis and Streptococcus mutans, while none could inhibit Listeria monocytogenes. Among the isolates, Bacillus subtilis ZH05, ZB03 and ZG025 showed resistance to most of the tested antibiotics and were considered unsafe. B. subtilis (4) and B. licheniformis (1) tolerated acidic pH and bile conditions, never the less were more tolerant in simulated intestinal conditions vis-a-vis gastric conditions. In 0·5% phenol concentrations, B. licheniformis ZH02 showed highest growth, while, B. subtilis ZG029 demonstrated highest auto-aggregation (65 ± 4·6) and hydrophobicity (23 ± 3·6) percentages (P < 0·05). The isolates lacked virulence genes (hblA, hblC, hblD, nhe, cytK and ces), and their cytotoxic percentage on Caco-2 cell lines was ˂15%. Overall, honeybees appear to be a good source of Bacillus species exhibiting typical in vitro probiotic properties, which could be of commercial interest.

In vitro and genetic screening of probiotic properties of lactic acid bacteria isolated from naturally fermented cow-milk and yak-milk products of Sikkim, India

A total of 272 isolates of lactic acid bacteria (LAB) were isolated from 22 samples of naturally fermented milk products of Sikkim in India viz. dahi, soft-variety chhurpi, hard-variety chhurpi, mohi and philu, out of which, 68 LAB isolates were randomly grouped on the basis of phenotypic characteristics, and were identified by 16S rRNA gene sequence analysis. Leuconostoc mesenteroides was the most dominant genus, followed by Leuc. mesenteroides subsp. jonggajibkimchii, Lactococcus lactis subsp. cremoris, Lc. lactis, Lc. lactis subsp. hordniae, Lc. lactis subsp. tructae, Enterococcus faecalis, E. italicus and E. pseudoavium. LAB strains were tested for probiotics attributes by in vitro and genetic screening, based on marker genes. LAB strains showed tolerance to pH 3.0, bile salt, resistance to lysozyme and β-galactosidase activity. Enterococcus faecalis YS4-11 and YS4-14 and Lactococcus lactis subsp. cremoris SC3 showed more than 85% of hydrophobicity. Genes clp L and tdc encoding for low pH tolerance, agu A and Ir1516 encoding for bile tolerance, LBA1446 gene encoding for BSH activity, map A, apf, mub 1 and msa encoding for mucosal binding property were detected. Gene mesY for bacteriocin production was detected only in Leuconostoc spp. Based on the in vitro and genetic screening of probiotic attributes, Leuc. mesenteroides; Leuc. mesenteroides subsp. jonggajibkimchii and Lc. lactis subsp. cremoris were tentatively selected for possible probiotic candidates.

Comparative evaluation for thermostability and gastrointestinal survival of probiotic Bacillus coagulans MTCC 5856

Thermal stability (D-value and pasteurization) and gastric acid resistance of spore forming and nonspore forming probiotic strains were evaluated in this study. Bacillus coagulans MTCC 5856 spores showed highest thermal resistance (D-value 35.71 at 90 °C) when compared with other Bacillus strains and Lactobacillus species. B. coagulans strains exhibited significantly higher resistance to simulated gastric juice (pH 1.3, 1.5, and 2.0) compared to Lactobacillus strains. It also showed high resistance to cooking conditions of chapati (whole wheat flour-based flatbread) (88.94% viability) and wheat noodles (and 94.56% viability), suggesting remarkable thermal resistance during food processing. Furthermore, B. coagulans MTCC 5856 retained 73% viability after microwave cooking conditions (300 s, at 260 °C) and 98.52% in milk and juice at pasteurization temperature (420 min, at 72 °C). Thus, B. coagulans MTCC 5856 clearly demonstrated excellent resistance to gastric acid and high temperature (90 °C), thereby suggesting its extended application in functional foods (milk, fruit juices, chapati, and wheat noodles) wherein high temperature processing is involved.

Sustainable Extraction of Chitin from Spent Pupal Shell of Black Soldier Fly

Chitin and its deacetylated derivative chitosan are used for application in areas as an agriculture, biomedicine, cosmetic, food, textile and chelating agent for wastewater treatment. The current extraction of chitin is based on a chemical process using hydrochloric acid and sodium hydroxide. The main disadvantage of the process is the generation of large volumes of acid and alkaline effluents, which require further treatment before release. Chitin was extracted from spent pupal shell of black soldier fly (BSF) by the microbial fermentation method using Bacillus lichenformis A6. The recovery rate of chitin content by the microbial fermentation method was found to be about 12.4%. The structures of BSF chitin and chitosan were further characterized by FTIR, XRD, and SEM. Our results showed that the chitin obtained from BSF was observed in α form. The crystalline index values of chitin and chitosan are 52.8% and 55.4%, respectively. The surface morphology was examined by SEM, revealing nanofiber structures. The spent pupal shell of BSF may be used as alternative chitin sources for various technological purposes.

Isolation and Characterization of Probiotic Bacillus subtilis MKHJ 1-1 Possessing L-Asparaginase Activity

The purpose of this study was to isolate functional Bacillus strains from Korean fermented soybeans and to evaluate their potential as probiotics. The L-asparaginase activity of MKHJ 1-1 was the highest among 162 Bacillus strains. This strain showed nonhemolysis and did not produce β-glucuronidase. Among the nine target bacteria, MKHJ 1-1 inhibited the growth of Escherichia coli, Pseudomonas aeruginosa, Shigella sonnei, Shigella flexneri, Klebsiella pneumoniae, Staphylococcus aureus, and Bacillus cereus. 16S rRNA gene sequence analysis resulted in MKHJ 1-1 identified as Bacillus subtilis subsp. stercoris D7XPN1. As a result of measuring the survival rate in 0.1% pepsin solution (pH 2.5) and 0.3% bile salt solution for 3 h, MKHJ 1-1 exhibited high acid resistance and was able to grow in the presence of bile salt. MKHJ 1-1 showed outstanding autoaggregation ability after 24 h. In addition, its coaggregation with pathogens was strong. Therefore, MKHJ 1-1 is a potential probiotic with L-asparaginase activity and without L-glutaminase activity, suggesting that it could be a new resource for use in the food and pharmaceutical industry.

Development of a semi-dynamic in vitro model and its testing using probiotic Bacillus coagulans GBI-30, 6086 in orange juice and yogurt

A dynamic system mimicking the gastrointestinal tract (GIT) conditions (fluids, pH, temperature, and residence time) was used to evaluate the behavior of Bacillus coagulans GBI-30, 6086 (BC) incorporated in yogurt and orange juice. BC counts were monitored in samples collected before the in vitro digestion, after initial contact with gastric fluids (30 min), static (1 h 15 min) and dynamic (2 h) stages in the gastric compartment, static (3 h) and dynamic (4 h) stages in the duodenal compartment, static (5 h) and dynamic (6 h) stages in the jejunal compartment, and after digestion. BC presented high survival in juice and yogurt over the digestion stages. The number of decimal reductions (γ) of BC caused by exposure to simulated GIT conditions was ≥0.89 in orange juice and ≥1.17 in yogurt. No differences (p ≥ 0.05) were observed on the survival of BC among the samples collected over the digestion in juice or yogurt, or between these matrices. After the in vitro digestion, BC counts were ≥7 log CFU/mL or g. Results show the great survival of BC under GIT conditions and suggest both, juice and yogurt as appropriate carries for delivering this probiotic to the diet. The semi-dynamic in vitro system was easily built and to operate, comprising an intermediate approach to assess the resistance of probiotic or potentially probiotic strains under simulated gut conditions.

Bacillus subtilis natto as a potential probiotic in animal nutrition

The growing global demand for animal products and processed meat has created a challenge for the livestock sector to enhance animal productivity without compromising product quality. The restriction of antibiotics in animal feeds as growth promoters makes the use of probiotics a natural and safe alternative to obtain functional foods that provide animal health and quality and to maintain food safety for consumers. To incorporate these additives into the diet, detailed studies are required, in which in vitro and in vivo assays are used to prove the efficacy and to ensure the safety of probiotic candidate strains. Studies on the use of Bacillus subtilis natto as a spore-forming probiotic bacterium in animal nutrition have shown no hazardous effects and have demonstrated the effectiveness of its use as a probiotic, mainly due to its proven antimicrobial, anti-inflammatory, antioxidant, enzymatic, and immunomodulatory activity. This review summarizes the recent scientific background on the probiotic effects of B. subtilis natto in animal nutrition. It focuses on its safety assessment, host-associated efficacy, and industrial requirements.

Quantifying the impact of eight unit operations on the survival of eight Bacillus strains with claimed probiotic properties

This study assessed the impact of eight unit operations [slow pasteurization, high-temperature short time (HTST) pasteurization, cooking, baking, drying, fermentation, supercritical carbon dioxide (CO₂), irradiation and extrusion] in different food matrices (milk, orange juice, meatballs, bread, crystallized pineapple, yogurt, orange juice, ground black pepper, snacks, and spaghetti) on the resistance of eight (Bacillus flexus Hk1 Bacillus subtilis Bn1, Bacillus licheniformis Me1, Bacillus mojavensis KJS3, Bacillus subtilis PXN21, Bacillus subtilis PB6, Bacillus coagulans MTCC 5856 and Bacillus coagulans GBI-30, 6086) Bacillus strains with claimed probiotic properties (PB). The number of decimal reductions (γ) caused by the unit operations varied (p < 0.05) amongst the PB. Most of the unit operations caused ≤ 2 γ of PB in the food matrices evaluated. Irradiation caused up to 4.9 γ (p < 0.05) amongst the PB tested. B. subtilis Bn1, B. mojavensis KJS3, B. licheniformis Me1, and B. coagulans GBI-30 showed higher resistance to most of the tested unit operations. These results indicate that the choice of PB for application in foods should also be based on their resistance to unit operations employed during processing. Finally, the high resistance of PB to the unit operations tested comprise valuable data for the development and diversification of probiotic foods with sporeforming strains with claimed probiotic properties.

Probiotic properties of lactic acid bacteria isolated from traditionally prepared dry starters of the Eastern Himalayas

The Himalayan people prepare dry and oval to round-shaped starter cultures to ferment cereals into mild-alcoholic beverages, which contain lactic acid bacteria (LAB) as one of the essential microbiota. There is no report on probiotic characters of LAB isolated from dry starters. Hence, we screened the probiotic and some functional properties of 37 LAB strains isolated from dry starters of the Eastern Himalayas viz. marcha, phab, paa, pee and phut. About 38% of the LAB strains showed high survival rate (> 50%) at pH 3 and 0.3% bile salts. Enterococcus durans BPB21 and SMB7 showed the highest hydrophobicity percentage of 98%. E. durans DMB4 and SMB7 showed maximum cholesterol assimilation activity. About 65% of the LAB strains showed the ability to produce β galactosidase. Majority of the strains showed phytase activity, whereas none of the strain showed amylase activity. About 86% of LAB strains showed an optimum tolerance of 10% ethanol concentration. Genetic screening of some probiotic and functional marker genes have also been analysed. The occurrence of clp L gene, agu A gene (survival of gastrointestinal tract conditions), apf, mub1 and map A gene (adhesion genes) was higher compared to other genes. The occurrence of bsh gene (bile salt tolerance) was detected in Pediococcus pentosaceus SMB13-1 and Enterococcus faecium BPB11. Gene ped B for pediocin with amplicon size of 375 bp was detected in E. durans DMB13 and Pediococcus acidilactici AKB3. Detection of nutritional marker gene rib A and fol P in some strains showed the potential ability to synthesize riboflavin and folic acid. LAB with probiotic and functional properties may be explored for food industry in future.

Pediococcus pentosaceus PP04 Ameliorates High-Fat Diet-Induced Hyperlipidemia by Regulating Lipid Metabolism in C57BL/6N Mice

In this study, Pediococcus pentococcus PP04 isolated from the Northeast pickled cabbage had good gastrointestinal tolerance and can colonize in the intestine stably. C57BL/6N mice were fed a high-fat diet to build animal models and treated with Pediococcus pentosaceus PP04 to evaluate the antihyperlipidemia effect. After 8 weeks, the indicators of hyperlipidemia, liver injury, and inflammation were measured. The treatment of P. pentosaceus PP04 reduced the gain of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), free fatty acids (FFAs), leptin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lipopolysaccharides (LPS), and tumor necrosis factor-α (TNF-α) significantly. The western blotting results suggested P. pentosaceus PP04 ameliorated high-fat diet-induced hyperlipidemia by the AMPK signaling pathway, which stimulated lipolysis via upregulation of PPARα and inhibited lipogenesis by downregulation of SREBP-1c, fatty acid synthase (FAS), and stearoyl-CoA desaturase-1 (SCD1) mainly. Furthermore, P. pentosaceus PP04 improved high-fat diet-induced oxidative stress effectively by triggering the Nrf2/CYP2E1 signaling pathway that enhanced the antioxidant activity including superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px).

Evaluation of the probiotic attributes of Bacillus strains isolated from traditional fermented African locust bean seeds (Parkia biglobosa), “daddawa”

Background

The involvement of probiotic cultures in food fermentation guarantees enhanced organoleptic properties and maximum consumer health benefits. In this study, isolated Bacillus cultures used in the fermentation of African locust bean seeds “Parkia biglobosa” into the food condiment “daddawa” were evaluated for probiotic attributes. Bacillus cereus strains BC1 and BC2 were tested for tolerance to acid, common salt (NaCl), and bile salt. Auto-aggregation and adhesion to epithelial cells, antibiotic sensitivity profile, hemolytic pattern, and antibacterial activity were also evaluated. To demonstrate further health benefit, spores of strain BC1 were investigated for anti-inflammatory potential employing the rat paw edema technique.

Results

Both Bacillus cereus strains showed antagonistic activity against pathogenic Escherichia coli and Staphylococcus aureus. BC1 was more acid-stress tolerant than BC2, maintaining 107.6% viability after 3 h incubation in MRS broth of pH 2.5. However, at 97.74% viability after incubation for 3 h, BC2 was more tolerant to 0.4 % bile salt. The Bacillus cereus strains were susceptible to all antibiotics tested with the exception of norfloxacin and thrived under high saline stress. Both strains were protease producers and non-hemolytic on sheep blood agar. The edema inhibition study revealed that spores of Bacillus cereus strain BC1 had anti-inflammation potential and produced no physiological toxicity on the animals.

Conclusion

These results indicate that the Bacillus cultures for “daddawa” production are good candidates for probiotics and have the potential for application in both animal and human formulations for increased health benefit to consumers.

The Step of Incorporation of Bacillus coagulans GBI-30 6086 Into "requeijão cremoso" Processed Cheese Does Not Affect Metabolic Homeostasis of Rats

Dairy product consumption is a common habit in Brazil. These products present a good matrix for probiotic incorporation. Thus, in this study the feasibility of producing a probiotic “requeijão cremoso” incorporated with Bacillus coagulans GBI-30 6086 in three different steps and its metabolic effect in an animal model for 2 weeks has been evaluated. Wistar adult health rats were randomized into one to five groups (n = 8 for each group): Control (C); “requeijão cremoso” without probiotic (RC); probiotic inoculated in the milk before pasteurization at 65°C/30 min (RPP); “requeijão cremoso” inoculated before the fusion step and consequently exposed to 90°C/5 min (RPF); and “requeijão cremoso” inoculated after fusion step, i.e., once the product temperature reached 50°C (RPAF). At the end of treatment, analysis of molecular markers of proteins of stress and antioxidant system, HSP 25, 60, 70 and 90, SOD and catalase were performed in the animals’ muscles by Western Blot technique. The HSP25, HSP90 and catalase levels of C, RPP, RPF, and RPAF were similar, indicating that the homeostasis remained unchanged. The incorporation of B. coagulans GBI-30 6086 in the “requeijão cremoso” was shown to be stable and the microorganism remained viable in all steps tested. The incorporation of the probiotic strain in the fusion stage facilitated the technological process, since it allowed a better homogenization of the product and did not affect the maintenance of the metabolic homeostasis of rats.

Isolation and characterization of Bacillus spp. strains as potential probiotics for poultry

Probiotics have become one of the potential solutions to global restriction on antibiotic use in food animal production. Bacillus species have been attractive probiotics partially due to their long-term stability during storage. In this study, 200 endospore-forming bacteria isolates were recovered from sourdough and the gastrointestinal tract (GIT) of young broiler chicks. Based on the production of a series of exoenzymes and survivability under stress conditions similar to those in the poultry GIT, 42 isolates were selected and identified by 16S rRNA gene sequencing. Seven strains with a profile of high enzymatic activities were further evaluated for sporulation efficiency, biofilm formation, compatibility among themselves (Bacillus spp.), and antagonistic effects against three bacteria pathogenic to poultry and humans: Enterococcus cecorum, Salmonella enterica, and Shiga-toxin-producing Escherichia coli. The strains from sourdough were identified as Bacillus amyloliquefaciens whereas the ones from the chicks' GIT were Bacillus subtilis. These strains demonstrated remarkable potential as probiotics for poultry.

Behavior of different Bacillus strains with claimed probiotic properties throughout processed cheese ("requeijão cremoso") manufacturing and storage

Even though spore-forming bacteria have been mainly linked to spoilage or foodborne pathogens vehiculated through foods, some strains of Bacillus can potentially present probiotic properties. The advantage of incorporating probiotic Bacillus strains in foods relies mainly on the fact that these microorganisms present high resistance to harsh processing conditions. "Requeijão cremoso" is a type of processed cheese highly appreciated in Brazil. During processing, this product is submitted to several harsh conditions (heating at 90 °C, for instance), leading to the inactivation of probiotic bacteria belonging to Lactobacillus and Bifidobacterium genera. That fact has precluded the development of probiotic "requeijão cremoso" products; however, probiotic Bacillus strains may comprise a promising alternative to overcome the low resistance of traditional probiotics to food processing. The objective of this study was to evaluate the behavior of different Bacillus strains with claimed probiotic properties throughout processed cheese ("requeijão cremoso") manufacturing. A total of five different Bacillus strains with claimed probiotic properties (B. coagulans MTCC 5856, B. coagulans GBI-30 6086, B. subtilis PXN 21, B. subtilis PB6, and B. flexus HK1) were individually inoculated at different stages of manufacture - curd pasteurization, coagulation, and fusion - of "requeijão cremoso" and their survival in each of these stages was determined. The survival of B. coagulans GBI-30 6086 was further assessed throughout "requeijão cremoso" production and shelf life (45 days at 6 °C). Besides, the chemical composition, level of proteolysis, and fatty acid profile of the treatments during shelf life were evaluated. The fusion stage was found as the most appropriate for the addition of B. coagulans GBI-30 6086, which allows the production of probiotic "requeijão cremoso" and facilitates the technological process while preventing the occurrence of final product recontamination.

The resistance of Bacillus, Bifidobacterium, and Lactobacillus strains with claimed probiotic properties in different food matrices exposed to simulated gastrointestinal tract conditions

The resistance of Bifidobacterium, Lactobacillus, and Bacillus strains with claimed probiotic properties in different food matrices was evaluated. Lactobacillus paracasei PXN 37, Lactobacillus acidophilus La-5, Bifidobacterium animalis subsp. lactis Bb-12, Bifidobacterium breve PXN 25, Bacillus subtilis PXN 21, Bacillus coagulans GBI30 6086 and Bacillus coagulans MTCC 5856 strains were inoculated in "requeijão cremoso" cheese, pasteurized orange juice, and bread. Further, the counts of the strains with claimed probiotic properties were determined throughout the products' shelf-life. Additionally, the survival (%), at the beginning and at the end of their shelf-life, of each strain with claimed probiotic properties inoculated in the three foods was estimated by using a static in vitro system simulating the gastric (pH 2), enteric I (pH 5) and enteric II (pH 7) phases of gastrointestinal tract (GIT). Overall, it has been found that the Bacillus strains with claimed probiotic properties showed greater viability than probiotic Bifidobacterium and Lactobacillus strains no matter the food studied. The percentage of survival of the Bacillus strains with claimed probiotic properties were always above 83%. The Bacillus strains with claimed probiotic properties were able to survive well in all the food matrices tested. Therefore, this study shows that these strains of Bacillus may comprise a feasible strategy for expanding the range of "probiotic food" choices given their high resistance to the composition of foods, manufacturing steps, and resistance to simulated GIT conditions.

In vitro probiotic properties of Bacillus sp isolated from biofloc reared genetically improved farmed tilapia (Oreochromis niloticus)

A study was conducted to investigate the probiotic potential of the bacterial species from biofloc reared genetically improved farmed tilapia (GIFT) using in vitro quantitative assays. Based on the morphological, biochemical and 16S rRNA sequencing analysis, isolated bacterial species from GIFT gut were identified as Bacillus infantis, Exiguobacterium profundum, Bacillus subtilis and Bacillus megaterium. The in vitro probiotic properties such as bile salt hydrolase activity, bile tolerance, growth at different bile concentrations, antibiotic susceptibility test, antimicrobial activity, auto aggregation test, bacterial adhesion to hydrocarbons and resistance to gastric acidity were performed. All the isolates showed higher resistance to bile tolerance test and growth of cultures was observed from 0.5 to 8% bile salt concentrations. The distinct zone of hydrolysis was marked in the tested isolates in bile salt hydrolysis activity. Except B. infantis, all the other three isolates were predominantly resistant to the tested antibiotics. Antimicrobial activity against three pathogens, viz. Vibrio parahaemolyticus, Vibrio harveyi and Aeromonas hydrophila was observed in all the isolates. E. profundum and B. subtilis showed improved auto aggregation. Enhanced resistance to bile salt adhesion to hydrocarbon and in vitro gastric acidity (pH 3) was seen in B. megaterium. It is one of such unique studies confirming the probiotic effect of Bacillus sp. isolated mainly from GIFT biofloc culture. B. subtilis and B. megaterium exhibited remarkable in vitro probiotic properties and thus can be recommended as a successful probiotic strain for fish farming.

Potential Use of Bacillus coagulans in the Food Industry

Probiotic microorganisms are generally considered to beneficially affect host health when used in adequate amounts. Although generally used in dairy products, they are also widely used in various commercial food products such as fermented meats, cereals, baby foods, fruit juices, and ice creams. Among lactic acid bacteria, Lactobacillus and Bifidobacterium are the most commonly used bacteria in probiotic foods, but they are not resistant to heat treatment. Probiotic food diversity is expected to be greater with the use of probiotics, which are resistant to heat treatment and gastrointestinal system conditions. Bacillus coagulans (B. coagulans) has recently attracted the attention of researchers and food manufacturers, as it exhibits characteristics of both the Bacillus and Lactobacillus genera. B. coagulans is a spore-forming bacterium which is resistant to high temperatures with its probiotic activity. In addition, a large number of studies have been carried out on the low-cost microbial production of industrially valuable products such as lactic acid and various enzymes of B. coagulans which have been used in food production. In this review, the importance of B. coagulans in food industry is discussed. Moreover, some studies on B. coagulans products and the use of B. coagulans as a probiotic in food products are summarized.

Phytase-Producing Potential and Other Functional Attributes of Lactic Acid Bacteria Isolates for Prospective Probiotic Applications

Wide variations among multifaceted-health benefitting attributes of probiotics fueled investigations on targeting efficacious probiotics. In the current study, lactic acid bacteria (LAB) isolated from poultry gut, feces of rat, chicken, human infants, and fermented foods were characterized for desired probiotic functional properties including the phytase-producing ability which is one of the wanted characteristics for probiotics for potential applications for upgrading animal nutrition, enhancing feed conversion, and minimizing anti-nutritional properties. Among 62 LAB isolates Weissella kimchii R-3 an isolate from poultry gut exhibited substantial phytase-producing ability (1.77 U/ml) in addition to other functional probiotic characteristics viz. hydrophobicity, autoaggregation, coaggregation with bacterial pathogens, and antimicrobial activity against pathogens. Survival of W. kimchii R-3 cells (in free and calcium alginate encapsulated state) was examined sequentially in simulated gastric and intestinal juices. Encapsulated cells exhibited better survival under simulated gut conditions indicating that encapsulation conferred considerable protection against adverse gut conditions. Furthermore, simulated gastric and intestinal juices with pepsin and pancreatin showed higher survival of cells than the juices without pepsin and pancreatin. W. kimchii R-3 due to its significant functional probiotic attributes may have prospective for commercial applications in human/animal nutrition.