The coming of age of probiotics

Comprehensive probiogenomics analysis of the commensal Escherichia coli CEC15 as a potential probiotic strain

BACKGROUND

Probiotics have gained attention for their potential maintaining gut and immune homeostasis. They have been found to confer protection against pathogen colonization, possess immunomodulatory effects, enhance gut barrier functionality, and mitigate inflammation. However, a thorough understanding of the unique mechanisms of effects triggered by individual strains is necessary to optimize their therapeutic efficacy. Probiogenomics, involving high-throughput techniques, can help identify uncharacterized strains and aid in the rational selection of new probiotics. This study evaluates the potential of the Escherichia coli CEC15 strain as a probiotic through in silico, in vitro, and in vivo analyses, comparing it to the well-known probiotic reference E. coli Nissle 1917. Genomic analysis was conducted to identify traits with potential beneficial activity and to assess the safety of each strain (genomic islands, bacteriocin production, antibiotic resistance, production of proteins involved in host homeostasis, and proteins with adhesive properties). In vitro studies assessed survival in gastrointestinal simulated conditions and adhesion to cultured human intestinal cells. Safety was evaluated in BALB/c mice, monitoring the impact of E. coli consumption on clinical signs, intestinal architecture, intestinal permeability, and fecal microbiota. Additionally, the protective effects of both strains were assessed in a murine model of 5-FU-induced mucositis.

RESULTS

CEC15 mitigates inflammation, reinforces intestinal barrier, and modulates intestinal microbiota. In silico analysis revealed fewer pathogenicity-related traits in CEC15, when compared to Nissle 1917, with fewer toxin-associated genes and no gene suggesting the production of colibactin (a genotoxic agent). Most predicted antibiotic-resistance genes were neither associated with actual resistance, nor with transposable elements. The genome of CEC15 strain encodes proteins related to stress tolerance and to adhesion, in line with its better survival during digestion and higher adhesion to intestinal cells, when compared to Nissle 1917. Moreover, CEC15 exhibited beneficial effects on mice and their intestinal microbiota, both in healthy animals and against 5FU-induced intestinal mucositis.

CONCLUSIONS

These findings suggest that the CEC15 strain holds promise as a probiotic, as it could modulate the intestinal microbiota, providing immunomodulatory and anti-inflammatory effects, and reinforcing the intestinal barrier. These findings may have implications for the treatment of gastrointestinal disorders, particularly some forms of diarrhea.

Development, characterization and probiotic encapsulating ability of novel Momordica charantia bioactive polysaccharides/whey protein isolate composite gels

In this study, a polysaccharide (MP1) with a molecular weight of 38 kDa was isolated from Momordica charantia which contains arabinose, galactose, xylose, and rhamnose. (MP1) was used to formulate composite gels with Whey Protein Isolate (WPI) that were characterized for their functional properties, microstructure, thermal resistance, probiotic encapsulating ability, and potential toward metabolic syndrome (MS). Results showed that the highest complex index was obtained at MP concentration of 2 %. MP-WPIs demonstrated superior (p < 0.05) water holding capacity and emulsifying properties than WPI gels. MP-WPIs also had higher (p < 0.05) thermal stability via TGA and DSC analysis. MP-WPI morphology was observed via SEM whereas protein structure as affected by MP concentration was studied using CLSM. Also, FTIR revealed that MP and WPI bonded mainly through electrostatic, hydrophobic and hydrogen interactions. More, MP-WPIs successfully enhanced probiotic Lactobacillus acidophilus (LA) survival upon freeze-drying with high encapsulation efficiency (98 %) and improved storage stability. MP-WPIs improved LA survival upon digestion suggesting a potential prebiotic activity. Finally, synbiotic formulation LA-MP-WPIs exhibited effective biological activity against MS. Therefore, MP-WPIs is a propitious strategy for effective probiotic gastrointestinal delivery with potential toward MS.

Characterization of Some Microorganisms from Human Stool Samples and Determination of Their Effects on CT26 Colorectal Carcinoma Cell Line

The present study aimed to isolate and identify the potential probiotic, pathobiont, and pathogenic microorganisms in the stool samples of 12 healthy individuals and evaluate their in vitro effects on cancer formation. A total of 83 strains were isolated from the stool samples and identified using MALDI-Biotyper. Fourteen of the isolates were identified as Candida spp., three isolates were identified as Cryptococcus neoformans, 55 isolates were identified as lactic acid bacteria, and the remaining isolates belonged to different 11 bacterial genera. Important microbial properties for cancer prevention and some probiotic properties were examined. All strains maintained their viability under acidic conditions and in media containing bile salts. Of the bacterial strains, 62.5% were resistant to ampicillin, chloramphenicol, gentamicin, erythromycin, kanamycin, penicillin, streptomycin, tetracycline, and vancomycin. All yeast strains were resistant to ketoconazole and susceptible to nystatin. The susceptibility of the strains to fluconazole, voriconazole, amphotericin B, and itraconazole varied. Fifty-nine percent of the strains produced EPS and 21.7% showed proteolytic activity (PA). Of the strains, 15.7% both produced exopolysaccharides (EPS) and had PA. The antioxidant activity (AOA) varied depending on the strains. The pathobiont and pathogenic microorganisms promoted tumor formation, while potential probiotic microorganisms had a suppressive effect on tumor formation (P > 0.01). One yeast (Candida kefyr MK17) and three lactic acid bacteria strains (Lacticaseibacillus paracasei MK73, Lactiplantibacillus plantarum MK55, Limosilactobacillus mucosae MK45) have superior potential thanks to their anticarcinogenic properties as well as tolerance to gastrointestinal tract conditions. Stool samples of each individual contain various potential probiotic, pathobiont, and pathogenic microorganisms.

The antagonistic activity of the synbiotic containing Lactobacillus acidophilus and pineapple residue FOS against pathogenic bacteria

Fructooligosaccharide is used widely in many foods and pharmaceutical industries and produced by using different ways such as extracting it from plants or producing it by using plants and microorganisms' enzymes. In a previous study, we extracted Fructosyltransferase (Ftase) enzyme from pineapple residue and produced FOS. In this study, we measured the antagonistic activity of two synbiotics, the first synbiotic containing Lactobacillus acidophilus and the produced FOS, the second synbiotic containing Lactobacillus acidophilus and standard FOS, against pathogenic bacteria (P. aeruginosa, E. coli, S. aureus and B cereus). The results showed that the antagonistic activity of both synbiotic types was very close, as there were no significant differences between them except in the antagonistic activity against S. aureus, there was a significant difference between the synbiotic containing the standard FOS, which was the highest in its antagonistic activity compared to the synbiotic containing the produced FOS in this study. The activity of the fructooligosaccharide (FOS) extracted from pineapple residue was evident in enhancing the activity of the probiotic bacteria (L. acidophilus), which had a major role in the production of acids and compounds that inhibited the pathogenic bacteria. The diameters of inhibition areas in the current study ranged between 19.33-28 mm, and E. coli was more susceptible to inhibition, followed by S. aureus, P. aeruginosa, and B. cereus, respectively.

The Therapeutic Strategies for Uremic Toxins Control in Chronic Kidney Disease

Uremic toxins (UTs) are mainly produced by protein metabolized by the intestinal microbiota and converted in the liver or by mitochondria or other enzymes. The accumulation of UTs can damage the intestinal barrier integrity and cause vascular damage and progressive kidney damage. Together, these factors lead to metabolic imbalances, which in turn increase oxidative stress and inflammation and then produce uremia that affects many organs and causes diseases including renal fibrosis, vascular disease, and renal osteodystrophy. This article is based on the theory of the intestinal-renal axis, from bench to bedside, and it discusses nonextracorporeal therapies for UTs, which are classified into three categories: medication, diet and supplement therapy, and complementary and alternative medicine (CAM) and other therapies. The effects of medications such as AST-120 and meclofenamate are described. Diet and supplement therapies include plant-based diet, very low-protein diet, probiotics, prebiotics, synbiotics, and nutraceuticals. The research status of Chinese herbal medicine is discussed for CAM and other therapies. This review can provide some treatment recommendations for the reduction of UTs in patients with chronic kidney disease.

The Anti-Obesity Effects of Lemon Fermented Products in 3T3-L1 Preadipocytes and in a Rat Model with High-Calorie Diet-Induced Obesity

Lemon (Citrus limon) has antioxidant, immunoregulatory, and blood lipid-lowering properties. This study aimed to determine the effect of the lemon fermented product (LFP) which is lemon fermented with Lactobacillus OPC1 to prevent obesity. The inhibition of lipid accumulation in 3T3-L1 adipocytes is examined using a Wistar rat model fed a high-fat diet to verify the anti-obesity efficacy and mechanism of LFP. Here, it was observed that LFP reduced cell proliferation and inhibited the lipid accumulation (8.3%) of 3T3-L1 adipocytes. Additionally, LFP reduced body weight (9.7%) and fat tissue weight (25.7%) of rats; reduced serum TG (17.0%), FFA (17.9%), glucose (29.3%) and ketone body (6.8%); and increased serum HDL-C (17.6%) and lipase activity (17.8%). LFP regulated the mRNA expression of genes related to lipid metabolism (PPARγ, C/EBPα, SREBP-1c, HSL, ATGL, FAS, and AMPK). Therefore, LFP reduces body weight and lipid accumulation by regulating the mRNA expression of genes related to lipid metabolism. Overall, our results implicate LFP as a potential dietary supplement for the prevention of obesity.

Improvement of Cutaneous Wound Healing via Topical Application of Heat-Killed Lactococcus chungangensis CAU 1447 on Diabetic Mice

Cutaneous wound healing comprises a complex systemic network. Probiotics, naturally extracted substances, medicine, and chemical compounds have been used for wound healing, but the application of postbiotics as therapeutic agents has yet to be explored. Our study shows potential beneficial effects of heat-killed Lactococcus chungangensis CAU 1447 on type 1 diabetic mice. The postbiotic strain significantly decreased the skin wound size. The activity of myeloperoxidase secreted from neutrophils also decreased. The molecular mechanism of wound healing was adjusted by important mediators, growth factors, chemokines, and cytokines. These elements regulated the anti-inflammatory activity and accelerated wound healing. To determine the role of the postbiotic in wound repair, we showed a similar taxonomic pattern as compared to the diabetic mice using skin microbiome analysis. These findings demonstrated that heat-killed Lactococcus chungangensis CAU 1447 had beneficial effects on wound healing and can be utilized as postbiotic therapeutic agents.

Probiotic and Antifungal Attributes of Levilactobacillus brevis MYSN105, Isolated From an Indian Traditional Fermented Food Pozha

The use of probiotics and antifungal capabilities of the lactic acid bacteria (LAB) isolated from different niches is a strategy to prepare functional cultures and biopreservatives for food/feed industries. In the present study, LAB strains isolated from an Indian traditional fermented food, Pozha, were evaluated for their probiotic properties and biocontrol potential. A total of 20 LAB isolates were selected from Pozha samples collected aseptically and screened for their antagonistic activity against Fusarium verticillioides. Among the bioactive isolates, Lacticaseibacillus brevis MYSN105 showed the highest antifungal activity in vitro, causing some morphological alterations such as damaged mycelia and deformed conidia. Cell-free supernatant (CFS) from L. brevis MYSN105 at 16% concentration effectively reduced the mycelial biomass to 0.369 g compared to 1.938 g in control. Likewise, the conidial germination was inhibited to 20.12%, and the seed treatment using CFS induced a reduction of spore count to 4.1 × 10⁶ spores/ml compared to 1.1 × 10⁹ spores/ml for untreated seeds. The internal transcribed spacer (ITS) copy number of F. verticillioides decreased to 5.73 × 10⁷ and 9.026 × 10⁷ by L. brevis MYSN105 and CFS treatment, respectively, compared to 8.94 × 10¹⁰ in control. The L. brevis MYSN105 showed high tolerance to in vitro gastrointestinal conditions and exhibited high adhesive abilities to intestinal epithelial cell lines. The comparative genome analysis demonstrated specific secondary metabolite region coding for bacteriocin and T3PKS (type III polyketide synthase) possibly related to survival and antimicrobial activity in the gut environment. Our results suggest that L. brevis MYSN105 has promising probiotic features and could be potentially used for developing biological control formulations to minimize F. verticillioides contamination and improve food safety measures.

The efficacy of three double-microencapsulation methods for preservation of probiotic bacteria

Lactic acid bacteria (LAB) are used as a probiotic alternative to antibiotics in livestock production. Microencapsulation technology is widely used for probiotic preservation. A variety of microencapsulation protocols have been proposed and compared based on chemicals and mechanical procedures. This study aimed to develop a double-encapsulated coating from alginate (1.5%) and chitosan (0.5%) by extrusion, emulsion, and spray drying methods using the LAB strains Lactobacillus plantarum strains 31F, 25F, 22F, Pediococcus pentosaceus 77F, and P. acidilactici 72N, and to monitor the basic probiotic properties of the encapsulated prototypes. The final products from each microencapsulation protocol were analysed for their appearance, probiotic properties and viable cell count. Using the spray drying method, particles smaller than 15 μm in diameter with a regular spherical shape were obtained, whereas the other methods produced larger (1.4–52 mm) and irregularly shaped microcapsules. After storage for 6 months at room temperature, the LAB viability of the spray-dried particles was the highest among the three methods. In all the LAB strains examined, the encapsulated LAB retained their probiotic properties in relation to acid-bile tolerance and antibacterial activity. This study highlights the efficacy of double-coating microencapsulation for preserving LAB properties and survival rate, and demonstrates its potential for probiotic application in livestock farms.

Screening of Probiotic Lactic Acid Bacteria Isolated from Fermented Pak-Sian for Use as a Starter Culture

The objective of this research was to evaluate the probiotic properties of lactic acid bacteria (LAB) isolated from fermented Pak-Sian, a traditional Thai food in the northeastern region of Thailand (Kalasin, Sakon Nakhon, Maha Sarakham, and Khon Kaen Provinces). A total of 61 LAB isolates isolated from selective MRS agar were screened by SDS-PAGE and identified by 16S rDNA analysis. Seventeen bacterial strains were found consisting of Pediococcus pentosaceus (6 strains) Lactiplantibacillus plantarum (5 strains), Levilactobacillus brevis (1 strain), Lactobacillus fermentum (3 strains), and Weissella cibaria (2 strains). A PH tree grouped 17 LAB strains into 5 clusters with three clusters only recorded from Sakon Nakhon Province. All strains were tested for probiotic properties. Results showed that 14 strains had the ability to resist pH 2.5 as resistant to bile salts and survive in gastric juices and the intestinal tract. LAB demonstrated antimicrobial activity against 4 pathogens: Staphylococcus aureus TISTR746, Salmonella typhimurium TISTR1472, Escherichia coli ATCC25922, and Bacillus cereus TISTR1449. Most LAB strains were resistant to all antibiotics tested, while some Lactobacillus strains were moderately susceptible to chloramphenicol, rifampicin, and ampicillin. None of the 14 strains produced biogenic amine and eight showed no hemolysis activity, indicating the safety of these strains. These 8 strains were selected to determine mucin adhesion capacity. Lactobacillus fermentum SK324 and Levilactobacillus brevis SK335 showed the highest adhesion capacity of 2.39 and 2.34%, respectively. These two strains showed promise as alternative starter cultures to improve probiotic health benefits of local fermented Pak-Sian products as a functional food.

In vitro validation studies for adhesion factor and adhesion efficiency of probiotic Bacillus licheniformis MCC 2514 and Bifidobacterium breve NCIM 5671 on HT-29 cell lines

Probiotic bacterial adhesion to the epithelial cell is a composite process and in vivo adhesion studies can be strengthened with the improved in vitro models for preliminary screening of potentially adherent strains. With this rationale, the study aimed is the first report to demonstrate the colonizing efficiency of probiotic Bacillus licheniformis MCC 2514 in comparison to Bifidobacterium breve NCIM 5671on HT-29 cell line. B. licheniformis (54.28 ± 0.99%) and Bif. breve (70.23 ± 0.85%) adhered in a higher percentage on fibronectin and mucin, respectively. However, the adhesion was higher for B. licheniformis when compared to Bif. breve. In adhesion score, B. licheniformis obtained about 138.85 ± 12.32, whereas Bif. breve got the score of 43.05 ± 9.12. The same trend continued in the adhesion percentage study, where B. licheniformis adhered 75.5 ± 5.2%, higher than Bif. breve which adhered 32.66 ± 3.2%. In invasion assay, both the bacteria significantly decreased the colonization of the pathogen Kocuria rhizophila ATCC 9341 about 97.32 ± 0.81% in the competitive assay, 97.87 ± 0.73% in exclusion assay and 82.19 ± 2.51% in displacement assay. The cytotoxicity effects of the test bacterial strains against HT-29 cell line through MTT assay determined no viability loss in the treated cells. Therefore, the data obtained from the in vitro studies showed that both B. licheniformis and Bif. breve had shown significantly good invasion on pathogen and adhesion capacity on HT-29 cell line.

Lactobacillus animalis pZL8a: a potential probiotic isolated from pig feces for further research

This study aimed to screen a potential anti-diarrheal probiotic for pigs to meet the growing demand for antibiotic alternatives in livestock. Six intestinal pathogens, Escherichia coli (O157: H7) ATCC 43888, Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 19115, Salmonella Typhimurium ATCC 14028, Shigella boydii ATCC 9207, and Staphylococcus haemolyticus ZSY2 were employed as indicator bacteria. Our result showed that Lactobacillus animalis pZL8a isolated from pig feces had extensive and higher antibacterial activity against indicator pathogens among 9 tested strains. In addition, valuable attributes of pZL8a such as great tolerance of low pH (3.0) and bile salts (0.3%), high-level adhesion to Caco-2 cells, and similar susceptibility to the reference strain Lactobacillus rhamnosus GG (LGG) were observed. Compared with control, pZL8a supplement significantly improved the level of immunoglobulin G (IgG), immunoglobulin M (IgM), and interleukin-2 (IL-2) in mouse serum. Therefore, L. animalis pZL8a was proposed as a potential probiotic for further research and hope to reduce or replace the application of antibiotics in animal production.

Physiological Characteristics and Anti-Diabetic Effect of Pediococcus pentosaceus KI62

The purpose of this study is to examine the physiological characteristics and anti-diabetic effects of Pediococcus pentosaceus KI62. The α-amylase and α-glucosidase inhibitory activity of P. pentosaceus KI62 was 94.86±3.30% and 98.59±0.52%, respectively. In MRS broth containing 3% maltodextrin inoculated by P. pentosaceus KI62, the amounts of short chain fatty acids (SCFA) were propionic acid 18.05±1.85 mg/kg, acetic acid 1.12±0.07 g/100 mL, and butyric acid 2.19±0.061 g/kg, and those of medium chain fatty acids (MCFA) were C8 0.262±0.031 mg/kg, C10 0.279±0.021 mg/kg, and C12 0.203±0.009 mg/kg. Compared to sixteen antibiotics, P. pentosaceus KI62 had the highest sensitivity to penicillin-G and rifampicin, as well as the highest resistance to vancomycin and ampicillin. The strain also showed higher leucine arylamidase and valine arylamidase activities than other enzyme activities, but it did not produce β-glucuronidase which is carcinogenic enzymes. The survival rate of P. pentosaceus KI62 in 0.3% bile was 91.67%. Moreover, the strain showed a 98.63% survival rate in pH 2.0. P. pentosaceus KI62 exhibits resistance to Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, and Staphylococcus aureus at rates of 29.41%, 38.10%, 51.72%, and 50.47%, respectively. P. pentosaceus (23.31%) showed a similar adhesion ability to L. rhamnosus GG, the positive control (24.49%). These results show that P. pentosaceus KI62 has possibility as a probiotic with anti-diabetic effects.

Assembly of propylene glycol alginate/β-lactoglobulin composite hydrogels induced by ethanol for co-delivery of probiotics and curcumin

Probiotics and curcumin can exhibit synergistic biological activities on the basis of a gut-brain axis, but are sensitive to environmental conditions, making it a challenge for their co-utilization. To meet the demand for high efficiency and convenience, both probiotics and curcumin were encapsulated within a propylene glycol alginate-based hydrogel delivery system, which was assembled using an ethanol-induced approach. The composite hydrogel was effective at sustaining the release of curcumin and protecting LGG cells in simulated gastrointestinal tract conditions. Moreover, it could also largely reduce the chemical degradation of curcumin and increase the survival of LGG during light exposure and long-term storage: up to 91.3 % of curcumin and 9.72 log CFU cm^-3 remained present throughout 4 weeks of storage. Results in this work demonstrate a low-energy and green approach to assemble a composite hydrogel with remarkable biocompatibility, which is considered as a desired delivery vehicle for co-delivery of probiotics and curcumin.

Probiotic Potential of Lactic Acid Starter Cultures Isolated from a Traditional Fermented Sorghum-Millet Beverage

The purpose of this study was to establish the probiotic potential of lactic acid bacteria (LAB) starter cultures, Lb. plantarum MNC 21, L. lactis MNC 24, and W. confusa MNC 20, isolated from a traditionally fermented sorghum-millet beverage from Uganda. The cultures were examined for tolerance to acid and bile salts, bile salt hydrolase (BSH) activity, antibiotic susceptibility, biogenic amine production, mucin degradation, hydrophobicity, auto-aggregation, adherence to the ileum, coaggregation, and antimicrobial properties against selected pathogenic species. Lb. rhamnosus yoba 2012, a known probiotic, was the reference. The isolates were tolerant to acid (pH = 3) and bile (1%). W. confusa MNC 20 and Lb. plantarum MNC 21 exhibited medium BSH activity (11-15 mm diameter of hydrolysis zone) while L. lactis and Lb. rhamnosus yoba 2012 exhibited low BSH activity (<10 mm diameter of hydrolysis zone). All isolates lacked mucolytic activity. Lb. plantarum MNC 21 and W. confusa MNC 20 produced agmatine. The candidate and reference microorganisms were resistant to 10 of 21 and 5 of 21 antibiotics, respectively. The isolates exhibited hydrophobic, auto-aggregation and coaggregation properties. These three properties were exhibited more (p < 0.05) by the reference than the potential probiotics. The ability of the potential probiotics to attach onto the goat ileum (7.3-8.0 log cfu/cm²) was comparable to that of Lb. rhamnosus yoba 2012 (7.6 log cfu/cm²). The four LAB inhibited E. coli, S. aureus, and S. enterica to the same extent (p < 0.05). The findings indicated potential probiotic activity of the starter cultures. However, further in vivo examination of these isolates is required to confirm their probiotic capabilities.

Multi-Product Lactic Acid Bacteria Fermentations: A Review

Industrial biotechnology is a continuously expanding field focused on the application of microorganisms to produce chemicals using renewable sources as substrates. Currently, an increasing interest in new versatile processes, able to utilize a variety of substrates to obtain diverse products, can be observed. A robust microbial strain is critical in the creation of such processes. Lactic acid bacteria (LAB) are used to produce a wide variety of chemicals with high commercial interest. Lactic acid (LA) is the most predominant industrial product obtained from LAB fermentations, and its production is forecasted to rise as the result of the increasing demand of polylactic acid. Hence, the creation of new ways to revalorize LA production processes is of high interest and could further enhance its economic value. Therefore, this review explores some co-products of LA fermentations, derived from LAB, with special focus on bacteriocins, lipoteichoic acid, and probiotics. Finally, a multi-product process involving LA and the other compounds of interest is proposed.

Effects of Frozen Storage on Viability of Probiotics and Antioxidant Capacities of Synbiotic Riceberry and Sesame-Riceberry Milk Ice Creams

According to many recent studies, ice cream was found to be an effective carrier of probiotics along the human gastrointestinal tract. While probiotics have long been known to improve gut health, prebiotic-supplemented ice creams have demonstrated properties that could be linked to various health benefits and improvement of the gut microbiota. In this study, riceberry and sesame-riceberry milk ice creams were supplemented with inulin, Lactobacillus casei 01 and Lactobacillus acidophilus LA5 to examine the changes of probiotic populations in different formulations of ice cream. The survivability of probiotics after 60 days of frozen storage and the level of viable cell tolerance towards the simulated gastrointestinal environment were also assessed, followed by sensory evaluation with 100 untrained panelists and determination of chemical qualities of ice cream samples. Findings revealed L. casei 01 to be more resistant to frozen storage compared to L acidophilus LA5, whereas addition of sesame milk and inulin were shown to minimize levels of viable cell loss following environmental and mechanical stress, suggesting enhanced probiotic activity. Significant reductions in probiotic viability were observed for all ice cream samples, however higher survival rates were observed in prebiotic-supplemented samples prior to and after 60 days of frozen storage. Probiotic cell counts in all samples exceeded the minimum recommended value (6 log CFU/g). In simulated gastric and bile fluid, all samples illustrated a significant change in probiotic levels, which significantly decreased with increase time of exposure to acidic and basic conditions. Probiotic strains in samples containing riceberry, sesame and inulin demonstrated greatest survivability as observed by reduction in pH and increased total acidity, with increased antioxidant and phenolic contents. On the other hand, changes in physicochemical properties of ice cream lowered overall sensory scores in terms of color and flavor. This study contributes to future development and applications of riceberry and sesame for inducement of synbiotic effects in novel probiotic products.

In vitro probiotic characterization of high GABA producing strain Lactobacilluas brevis DSM 32386 isolated from traditional “wild” Alpine cheese

Purpose

γ-Aminobutyric acid (GABA) is recognised as a potential metabolic bioactive food ingredient with increasing evidence of its effects on the gut-brain axis and systemic metabolic health. Different lactic acid bacteria are capable of producing GABA, particularly strains of Lactobacillus brevis. In this study, we characterized a Lb. brevis isolated from traditional alpine cheese (Lb. brevis DSM 32386) for its ability to accumulate high levels of GABA in the culture medium and for other important probiotic phenotypic traits.

Methods

In vitro analysis were used to study the Lb. brevis DSM 32386 probiotic traits and the gene expression involved in GABA production

Result

Lactobacillus brevis DSM 32386 converted monosodium glutamate to GABA more efficiently than the type strain Lb. brevis DSM 20054, resulting in more than 200% of GABA produced. This ability seemed to be related to the higher transcriptional activation of the gene encoding for the glutamate (gad) decarboxylase antiporter (gadC) and regulator (gadR). Lactobacillus brevis DSM 32386 performed well in vitro under the stress conditions mimicking the gastro-intestinal tract, being resistant to acid pH (pH 2.5) and growing in simulated pancreatic fluid and 0.3% ox-bile.

Conclusion

These preliminary studies indicate that Lb. brevis DSM 32386 holds promise as a starter for GABA-rich dairy fermented foods and possibly a promising next-generation probiotic microorganism in the context of the gut (microbiota):brain axis.

Survival and Behavior of Encapsulated Probiotics (Lactobacillus plantarum) in Calcium-Alginate-Soy Protein Isolate-Based Hydrogel Beads in Different Processing Conditions (pH and Temperature) and in Pasteurized Mango Juice

Hybrid alginate-soy protein isolate-based hydrogel beads were prepared and evaluated to enhance the survival of the encapsulated probiotics (Lactobacillus plantarum) during heat processing to incorporate in mango juice. The solutions of sodium alginate-soy protein isolate (SA-SPI) with probiotic cells were dropped into the gelation bath containing calcium chloride (3% w/v) solution to develop various types of hydrogel beads. The level of survival of probiotics in encapsulated beads under acidic conditions (pH 2, 3, and 6.5) and bile salt (0.5 and 1.0% w/v) was evaluated. The survival of the encapsulated probiotics to thermal processing was evaluated by treating the beads in saline solution (0.9% w/v) at 30, 50, 63, and 72°C. The encapsulated probiotic bacteria were found alive even after treatment at 72°C for 90 s. Most of the free cells did not survive at the temperature higher than 50°C and very low pH (pH 2 and 3). The survival of probiotic cells was found higher with the hybrid hydrogel beads containing alginate and soy protein isolate (1:8 w/w). Furthermore, mango juice fortified with encapsulated L. plantarum in hydrogel beads was subjected to thermal pasteurization at 72°C for 90 s.

Bioremediation and biomass production from the cultivation of probiotic Saccharomyces boulardii in parboiled rice effluent

The parboilization of rice generates 2 L of effluent per kilogram of processed grain. Several methodologies have previously been tested with the aim of reducing the environmental impact of this effluent. The objective of this study was to evaluate the bioremediation of parboiled rice effluent supplemented with sucrose or residual glycerol from the biodiesel during the cultivation of the Saccharomyces boulardii probiotic. In the first stage of the experiment, cultures were grown in orbital shaker, and five media compositions were evaluated: 1) parboiled rice effluent; 2) effluent supplemented with 1% sucrose; 3) effluent supplemented with 3% sucrose; 4) effluent supplemented with 15 g.L^-1 of biodiesel glycerol and 5) standard yeast culture medium (YM). The addition of 1% of sucrose generated the most promising results in terms of cell viability, removal of nitrogen, phosphorus and chemical oxygen demand (COD). From these results, four independent cultures were grown in a bioreactor using effluent +1% of sucrose as the medium. This assays generated a mean of 3.8 g.L^-1 of biomass, 1.8 × 10¹¹ CFU.L^-1, and removal of 74% of COD and 78% of phosphorus. Therefore, the cultivation of Saccharomyces boulardii in parboiled rice effluent supplemented with 1% sucrose may represent a viable method by which the environmental impact of this effluent can be reduced while simultaneously producing probiotic culture for use in animal production.

In vitro and in vivo evidences for innate immune stimulators lactic acid bacterial starters isolated from fermented camel dairy products

Probiotics are commensals with special characteristics that are essential for the development of the immune system, and may protect mucosal surfaces against pathogens. In this study, a total of 40 lactic acid bacteria (LAB) were isolated from different raw and fermented camel's milk samples collected from Saudi Arabia (Makkah area) and Egypt (Fayoum), and tested for the probiotic properties. Among them, Pro 4 and Pro 7 isolates exhibited excellent probiotic potential including bile salt (0.2-0.6%), phenol tolerance (0.2-0.4%) and salt tolerance (0.0-10%). Furthermore, both strains exhibited antimicrobial activity against wide range of food-borne pathogens and Dermatophytes with average zone inhibition of 37.5, 35.5, 34.5, 27.5, 25 and 23.5 mm for Staphylococcus aureus, Trichophyton mentagrophytes, Escherichia coli, Listeria monocytogens, Candida albicans and Salmonella typhi, respectively. Furthermore, the in vivo study indicated that these strains significantly improved the mucosal immune responses through an increase in expression of TLR2 and IFNγ mRNA in mice intestine as well as increased the synthesis of polyclonal IgG, IgM and IgA in mice blood sera. Accordingly, due to these unique probiotic properties, both selected strains could be potentially used as probiotic starter cultures for fermented dairy foods as well as functional food and health products.

A Sensitive and Rapid Method to Determin the Adhesion Capacity of Probiotics and Pathogenic Microorganisms to Human Gastrointestinal Mucins

Mucus is the habitat for the microorganisms, bacteria and yeast that form the commensal flora. Mucins, the main macromolecules of mucus, and more specifically, the glycans that cover them, play essential roles in microbial gastrointestinal colonization. Probiotics and pathogens must also colonize mucus to have lasting positive or deleterious effects. The question of which mucin-harboured glycan motifs favour the adhesion of specific microorganisms remains very poorly studied. In the current study, a simple test based on the detection of fluorescent-labeled microorganisms raised against microgram amounts of mucins spotted on nitrocellulose was developed. The adhesion of various probiotic, commensal and pathogenic microorganisms was evaluated on a panel of human purified gastrointestinal mucins and compared with that of commercially available pig gastric mucins (PGM) and of mucins secreted by the colonic cancer cell line HT29-MTX. The latter two proved to be very poor indicators of adhesion capacity on intestinal mucins. Our results show that the nature of the sialylated cores of O-glycans, determined by MALDI MS-MS analysis, potentially enables sialic acid residues to modulate the adhesion of microorganisms either positively or negatively. Other identified factors affecting the adhesion propensity were O-glycan core types and the presence of blood group motifs. This test should help to select probiotics with enhanced adhesion capabilities as well as deciphering the role of specific mucin glycotopes on microbial adhesion.

New lactic acid bacteria for skin health via oral intake of heat-killed or live cells

Lactic acid bacteria play an essential role in the food industry in the manufacture of many fermented products (cheese, yogurt, fermented vegetables, etc.). Application of these organisms is now being extended to the area of health improvement, as their probiotic activities become known. Probiotics are defined as viable microorganisms that exert a beneficial effect on the health of the host when they are ingested in sufficient quantity. Lactic acid bacteria and bifidobacteria isolated from the human intestine are the most common probiotics used for human consumption. The development of new probiotics with new beneficial effects is eagerly awaited in the food industry. This review introduces Lactococcus, which are one of the genera of lactic acid bacteria and are mainly isolated from dairy products and fermented vegetables, as new probiotics, focusing especially on Lactococcus lactis H61, which improves skin status in Japanese women with oral intake of heat‐killed or live cells. The deduced mechanisms associated with the beneficial effects of strain H61 are also discussed.

Beneficial psychological effects of novel psychobiotics in diabetic rats: the interaction among the gut, blood and amygdala

Type 2 diabetes mellitus (T2DM) can lead to major complications such as psychiatric disorders which include depressive and anxiety-like behaviors. The association of the gut-brain axis in the development of such disorders, especially in T2DM, has been elucidated; however, gut dysbiosis is also reported in patients with T2DM. Hence, the regulation of the gut-brain axis, in particular, the gut-amygdala, as a vital region for the regulation of behavior is essential. Thirty-five male Wistar rats were divided into six groups. To induce T2DM, treatment groups received high-fat diet and 35 mg/kg streptozotocin. Then, supplements of Lactobacillus plantarum, inulin or their combination were administered to each group for 8 weeks. Finally, the rats were sacrificed for measurement of blood and tissue parameters after behavioral testing. The findings demonstrated the favorable effects of the psychobiotics (L. plantarum, inulin or their combination) on oxidative markers of the blood and amygdala (superoxide dismutase, glutathione peroxidase, malondialdehyde and total antioxidant capacity), as well as on concentrations of amygdala serotonin and brain-derived neurotrophic factor, in the diabetic rats. In addition, beneficial effects were observed on the elevated plus maze and forced swimming tests with no change in locomotor activity of the rats. There was a strong correlation between the blood and amygdala oxidative markers, insulin and fasting blood sugar with depressive and anxiety-like behaviors. Our results identified L. plantarum ATCC 8014 and inulin or their combination as novel psychobiotics that could improve the systemic and nervous antioxidant status and improve amygdala performance and beneficial psychotropic effects.

Effect of processing on nutritive values of milk protein

Milk is an essential source of nutritionally excellent quality protein in human, particularly in vegan diet. Before consumption, milk is invariably processed depending upon final product requirement. This processing may alter the nutritive value of protein in a significant manner. The processing operations like thermal treatment, chemical treatment, biochemical processing, physical treatments, nonconventional treatments, etc. may exert positive or negative influence on nutritional quality of milk proteins. On one side, processing enhances the nutritive and therapeutic values of protein while on other side intermediate or end products generated during protein reactions may cause toxicity and/or antigenicity upon consumption at elevated level. The review discusses the changes occurring in nutritive quality of milk proteins under the influence of various processing operations.

Probiotics: From Isolation to Application

Probiotics have become highly recognized as supplements for humans and animals because of their beneficial effects on health and well-being. The present review aims to provide an overview of different steps through which microbial strains become applicable probiotics in food and/or feed industries. Isolation of potential probiotic strains is the first step. Lactic acid bacteria are the most frequently used microorganisms as probiotics, which can be isolated from human, animal, plant, and environment. The next steps are identification of the isolates and characterization of them based on the main selection criteria for any potential probiotic microorganism, including resistance to gastric acidity and bile salt, adherence to mucus and/or intestinal epithelial cells and cell lines, and antimicrobial and antagonism activity against potentially pathogenic microbes. There are additional probiotic properties that may be considered for selection of probiotic strains with specific effects, such as cholesterol reduction ability, antioxidant activity, or cytotoxic effect against cancer cells. However, a potential probiotic does not need to fulfill all such selection criteria. As the last step, safety status of probiotics for humans is verified by taxonomy clarification, in vitro and in vivo tests, human trials, and genome sequencing.

Lactic acid bacteria isolated from yak milk show probiotic potential

Probiotic industries strive for new, efficient and promising probiotic strains that impart a positive impact on consumer health. Challenges are persisting in isolation, screening, and selection of the new indigenous probiotic strains. In the present research, we explored the probiotic potential of 17 lactic acid bacteria isolated from Yak milk in a series of in vitro tests. We also demonstrated their health benefits, i.e., cholesterol degradation, lactose digestion, antimicrobial activity, antioxidant, and anticancer activities. Principal component analysis revealed that more than 50% of the strains fulfilled the examined criteria, e.g., survival in acidic pH, bile concentrations, and adherent property. Approximately all the strains produced antimicrobial substances against the maximum number of tested strains including clinical strains. Most strains degraded cholesterol in comparison to the reference probiotic strain whereas strain Yc showed 1.5 times higher the degradation efficiency of the control strain. Lan4 strain exhibited remarkable anticancer activity and induced the maximum apoptosis (87%) in the Hela cells and was non-toxic to the non-cancerous HEK293 cells. Around ten strains showed positive lactose digestion. Overall, this can be concluded that selected lactic acid bacteria revealed excellent probiotic properties along with desirable health benefits. These strains need to be further investigated in details for their application in the development of novel probiotic preparations for the improvement of public health.

The cell wall compound of Saccharomyces cerevisiae as a novel wall material for encapsulation of probiotics

Yeast cell wall is known as a food grade ingredient which is recently being used increasingly as a novel coating for encapsulation of different materials in the food industry. This application is limited to core materials smaller than yeast in size. In this study, we have tried to encapsulate larger particles by crushing yeast cells. Hence, probiotic bacteria of Lactobacillus acidophilus and Bifidobacterium bifidum were encapsulated firstly by calcium alginate using the emulsion method and these microbeads were coated again by Saccharomyces cerevisiae cell wall compound and another layer of calcium alginate. The average diameter of microcapsules for single layer microbeads (M), microbeads coated by two layers of alginate (MCA), and microbeads coated by a layer of yeast cell and two layers of alginate (MCYA) were 54.25±0.18, 77.43±8.24 and 103.66±13.33μm, respectively. In simulated gastrointestinal conditions, there was a significant (P<0.05) enhancement in resistance of L. acidophilus when applying a layer of S. cerevisiae cell wall compound. For MCA and MCYA after 2h exposure to simulated gastric juice, it was revealed a log reduction of 1.53±0.1 and 1.1±0.02 with pH1.55 and in simulated intestinal juice, 2.92±0.04 and 2.42±0.06 with 0.6% bile after previous 1h incubation in gastric conditions, respectively. It can be concluded that the cell wall compound of S. cerevisiae is a suitable protective coating for probiotics and it can improve the survival of probiotics within food products.

Probiotics, prebiotics, and microencapsulation: A review

The development of a suitable technology for the production of probiotics is a key research for industrial production, which should take into account the viability and the stability of the organisms involved. Microbial criteria, stress tolerance during processing, and storage of the product constitute the basis for the production of probiotics. Generally, the bacteria belonging to the genera Lactobacillus and Bifidobacterium have been used as probiotics. Based on their positive qualities, probiotic bacteria are widely used in the production of food. Interest in the incorporation of the probiotic bacteria into other products apart from dairy products has been increasing and represents a great challenge. The recognition of dose delivery systems for probiotic bacteria has also resulted in research efforts aimed at developing probiotic food outside the dairy sector. Producing probiotic juices has been considered more in the recent years, due to an increased concern in personal health of consumers. This review focuses on probiotics, prebiotics, and the microencapsulation of living cells.

Traditional Cereal Food as Container of Probiotic Bacteria “Lb. rhamnosusGG”: Optimization by Response Surface Methodology

This research paper aims at optimizing three parameters involved in solid state fermentation (SSF) usingLactobacillus rhamnosusGG (LGG) to improve a traditional cereal food “Bsissa” in order to elaborate a new probiotic fermented breakfast cereal. A Box-Behnken experimental design was used and the optimal fermentation conditions were liquid to solid ratio: 1.2 (vw−1), fermentation time: 12 h, and sucrose concentration: 10.48 g (100 g DM)−1. Under these conditions, the viable LGG cells, the free amino nitrogen content, and the total acidity were obtained to be9.1 log10⁡(cfu g-1), 12.95 (mg g−1), and 6.46 (μmol g−1), respectively. After three weeks of refrigerated storage, the viability of LGG in the fermented Bsissa was8.23 log10⁡(cfu g-1). This study shows a new possibility to make an acceptable nonfermented dairy product based mainly on cereals, leguminous plants, spices, and aromatic herbs, which are suitable substrates able to support the high probiotic viability.

Surfacing role of probiotics in cancer prophylaxis and therapy: A systematic review

Cancers figure among the most important causes of morbidity and mortality worldwide. Cancer and its associated infections are always complicated even when specific cancer regimens are available. It is well proved that Lactobacillus and other probiotic bacteria can modulate-ameliorate specific mechanisms against various infections including cancers. The present systematic review is intended to focus on the 'cellular and molecular mechanisms' of probiotic bacteria in the prevention and treatment of various cancers. The clinical and experimental findings of various studies explain the mechanisms such as apoptosis, antioxidant activity, immune response and epigenetics and illustrate the role of probiotics in cancer management and prophylaxis. In addition, the present review also discusses the safety aspects of probiotics when they are used in therapeutic and nutritional diet management. However, further investigations are required to reveal the effectiveness of probiotics in cancer treatment in clinical settings.

Effects of Culture, pH and Fat Concentration on Melting Rate and Sensory Characteristics of Probiotic Fermented Yellow Mombin (Spondias mombin L) Ice Creams

Twelve fermented yellow mombin ice creams were produced with different starter cultures (Lactobacillus acidophilus 74-2, L. acidophilus LAC 4 and yoghurt starter culture), final pH (4.5 and 5) and concentrations of added cream (5 and 10%). Probiotic culture stability, melting properties and sensory acceptance were evaluated in ice cream samples. The mixes were frozen and stored for 105 days at -18°C. The melting rates were lower for samples with a pH of 4.5. Both probiotic cultures resisted the freezing process and, although a tendency for the counts to decrease during storage was detected, they were still higher than 10 6 cfu/g after 105 days, even in products with a pH of 4.5. A pH 4.5, 5% cream and L. acidophilus LAC 4 ice cream received significantly higher sensory scores when compared with pH 5, 10% cream and L. acidophilus 74-2 ice cream. The fermented yellow mombin ice cream was a suitable food for the delivery of L. acidophilus strains, with excellent viability and acceptable sensory characteristics.

The therapeutic potential of antibiotics and probiotics in the treatment of pouchitis

Pouchitis is the most frequent long-term complication of pouch surgery for ulcerative colitis. There is consistent evidence on the implication of bacterial flora in the pathogenesis of pouchitis, and there is evidence for a therapeutic role of antibiotics and probiotics in therapy of this disease. Antibiotics, particularly ciprofloxacin and metronidazole, are the mainstay of treatment for acute pouchitis. In chronic refractory pouchitis, after having excluded other diagnoses (infections, Crohn's disease of the pouch, ischemia and irritable pouch), antibiotic combination therapy is the treatment of choice. The highly concentrated probiotic mixture VSL#3 has been shown to be effective in prevention of pouchitis onset and in maintaining antibiotic-induced remission.