Determining antioxidant activities of lactobacilli cell-free supernatants by cellular antioxidant assay: a comparison with traditional methods

Evaluation of Functional Properties of Some Lactic Acid Bacteria Strains for Probiotic Applications in Apiculture

This study evaluates the suitability of three lactic acid bacteria (LAB) strains-Lactiplantibacillus plantarum, Lactobacillus acidophilus, and Apilactobacillus kunkeei-for use as probiotics in apiculture. Given the decline in bee populations due to pathogens and environmental stressors, sustainable alternatives to conventional treatments are necessary. This study aimed to assess the potential of these LAB strains in a probiotic formulation for bees through various in vitro tests, including co-culture interactions, biofilm formation, auto-aggregation, antioxidant activity, antimicrobial activity, antibiotic susceptibility, and resistance to high osmotic concentrations. This study aimed to assess both the individual effects of the strains and their combined effects, referred to as the LAB mix. Results indicated no mutual antagonistic activity among the LAB strains, demonstrating their compatibility with multi-strain probiotic formulations. The LAB strains showed significant survival rates under high osmotic stress and simulated gastrointestinal conditions. The LAB mix displayed enhanced biofilm formation, antioxidant activity, and antimicrobial efficacy against different bacterial strains. These findings suggest that a probiotic formulation containing these LAB strains could be used for a probiotic formulation, offering a promising approach to mitigating the negative effects of pathogens. Future research should focus on in vivo studies to validate the efficacy of these probiotic bacteria in improving bee health.

Enhancing food preservation with postbiotic metabolites γ-aminobutyric acid (GABA) and bacteriocin-like inhibitory substances (BLIS) produced by Lactobacillus brevis C23 co-cultures in plant-based medium

Lactic acid bacteria (LAB) can produce γ-aminobutyric acid (GABA) with antioxidant properties and sedative effects when it binds to the GABA receptor in the human brain. LAB can also produce bacteriocin-like inhibitory substances (BLIS) with antimicrobial capabilities during carbohydrate fermentation. GABA and BLIS are natural compounds with potential health benefits and food preservation properties. Lactobacillus brevis C23 was co-cultured with three different LABs as inducers, which produced the highest GABA content and BLIS activity. They were cultured in various plant-based media to obtain an edible and better-tasting final product over commercially available media like MRS broth. A coconut-based medium with additives was optimized using response surface methodology (RSM) to increase GABA and BLIS production. The optimized medium for maximum GABA production (3.22 ± 0.01 mg/mL) and BLIS activity (84.40 ± 0.44%) was a 5.5% coconut medium containing 0.23% glucose, 1.44% Tween 20, 0.48% L-glutamic acid, and 0.02% pyridoxine. Due to the presence of GABA, the cell-free supernatant (CFS) as a postbiotic showed higher antioxidant activity than other food preservatives like nisin and potassium sorbate. Finally, microbiological tests on food samples showed that the postbiotic was more effective than other preservatives at combating the growth of LAB, molds and coliform bacteria, making it a possible food preservative.

Potential of postbiotics for the treatment of metabolic disorders

Postbiotics, the next generation of probiotics, are extracts that are free of living and nonviable bacteria and show strong modulatory effects on the gut flora. Examples include vitamin B12, vitamin K, folate, lipopolysaccharides, enzymes, and short-chain fatty acids (SCFAs), representing a subset of essential nutrients commonly found in the human diet. Postbiotics have been observed to demonstrate antiobesity and antidiabetic effects through a variety of mechanisms. These pathways primarily involve an elevation in energy expenditure, a decrease in the formation and differentiation of adipocytes and food intake, modification of lipid and carbohydrate absorption and metabolism, and regulation of gut dysbiosis. Based on these above effects and mechanisms, the use of postbiotics can be considered as potential strategy for the treatment of metabolic disorders.

Strong Activity and No Resistance Induction Exerted by Cell-Free Supernatants from Lacticaseibacillus rhamnosus against Mono-Species and Dual-Species Biofilms of Wound Pathogens in In Vivo-like Conditions

It is widely agreed that microbial biofilms play a major role in promoting infection and delaying healing of chronic wounds. In the era of microbial resistance, probiotic strains or their metabolic products are emerging as an innovative approach for the treatment of hard-to-heal (chronic) wounds due to their antimicrobial, healing, and host immune-modulatory effects. In this study, we aimed to investigate the potential of cell-free supernatants (CFS) from Lacticaseibacillus rhamnosus GG against mono- and dual-species biofilms of wound pathogens in a 3D in vitro infection model. Mature biofilms of Pseudomonas aeruginosa and Staphylococcus aureus were obtained on collagen scaffolds in the presence of a simulant wound fluid (SWF) and treated with CFS at different doses and time intervals. At 1:4 dilution in SWF, CFS caused a marked reduction in the colony forming-unit (CFU) numbers of bacteria embedded in mono-species biofilms as well as bacteria released by the biofilms in the supernatant. CFU count and electron microscopy imaging also demonstrated a marked antibiofilm effect against dual-species biofilms starting from 8 h of incubation. Furthermore, CFS exhibited acceptable levels of cytotoxicity at 24 h of incubation against HaCaT cells and, differently from ciprofloxacin, failed to induce resistance after 15 passages at sub-inhibitory concentrations. Overall, the results obtained point to L. rhamnosus GG postbiotics as a promising strategy for the treatment of wound biofilms.

Metabolomics: Challenges and Opportunities in Systems Biology Studies

Metabolomics can provide diagnostic, prognostic, and therapeutic biomarker profiles of individual patients because a large number of metabolites can be simultaneously measured in biological samples in an unbiased manner. Minor stimuli can result in substantial alterations, making it a valuable target for analysis. Due to the complexity and sensitivity of the metabolome, studies must be devised to maintain consistency, minimize subject-to-subject variation, and maximize information recovery. This effort has been aided by technological advances in experimental design, rodent models, and instrumentation. Proton Nuclear Magnetic Resonance (1H-NMR) spectroscopy of biofluids, such as plasma, urine, and faeces provide the opportunity to identify biomarker change patterns that reflect the physiological or pathological status of an individual patient. Metabolomics has the ultimate potential to be useful in a clinical context, where it could be used to predict treatment response and survival and for early disease diagnosis. During drug treatment, an individual's metabolic status could be monitored and used to predict deleterious effects. Therefore, metabolomics has the potential to improve disease diagnosis, treatment, and follow-up care. In this chapter, we demonstrate how a metabolomics study can be used to diagnose a disease by classifying patients as either healthy or pathological, while accounting for individual variation.

Healing wounds, defeating biofilms: Lactiplantibacillus plantarum in tackling MRSA infections

Introduction

Methicillin-resistant Staphylococcus aureus (MRSA) infections are well-known hospital-borne infections and are a major contributing factor to global health concerns of antimicrobial resistance due to the formation of biofilms. Probiotics are known to assist in the healing of wounds through immunomodulation and also possess anti-pathogen properties via competitive inhibition. The probiotic bacterium, Lactiplantibacillus plantarum MTCC 2621 and its cell-free supernatant (Lp2621) have previously been reported to have antibacterial, excellent antioxidant, and wound healing activity in in vitro conditions and wounds contaminated with S. aureus in mice.

Methods

In the current study, we evaluated its anti-MRSA, biofilm inhibition and eradication efficacy, immunomodulatory activity in THP-1 cells, and wound healing potential in wounds contaminated with MRSA infection in mice.

Results

In agar well diffusion assay, Lp2621 showed anti-MRSA activity and revealed dose-dependent inhibition and eradication of biofilm by crystal violet assay as well as by Confocal Scanning Laser Microscopy (CLSM) analysis. Further, Lp2621 showed immunomodulatory activity at varied concentrations as measured by IL-6 and IL-10 gene expression in THP-1 cells. Similar findings were observed in serum samples of mice after treatment of excision wound contaminated with MRSA infection by Lp2621 gel, as evident by expression of IL-6 (pro-inflammatory) and IL-10 (anti-inflammatory) cytokines.

Conclusions

Overall, our results show that Lp2621 has potent anti-MRSA and antioxidant properties and can prevent and eliminate biofilm formation. It also showed promise when applied to mice with MRSA-infected wounds.

Salt tolerant Pseudomonas taiwanensis PWR-1 in combination with a reduced dose of mineral fertilizers improves the nutritional and antioxidant properties of wheatgrass grown in saline soil

Salt-tolerant plant growth promoting rhizobacteria (ST-PGPR) are known to ameliorate salt stress in plants by various mechanisms. The current study aims to investigate the role of an ST-PGPR strain Pseudomonas taiwanensis PWR-1 applied along with a reduced dose of mineral fertilizers (N, P, and K) in the improvement of the antioxidant and nutritional properties of wheatgrass (Triticum aestivum L.) grown in saline soil. Application of P. taiwanensis PWR-1 along with 50% of the recommended dose of mineral fertilizers resulted in a significant improvement of growth parameters including shoot length (22.79%), root length (20.38%), fresh weight (13.15%), dry weight (92.34%), vigor index (13.36%), and relative water content (48.24%). The combined application of PWR-1 and mineral fertilizers increased the production of osmoprotectants (proline, total soluble sugars, glycine betaine), antioxidants (SOD, POD, APX, CAT, PPO, and reduced glutathione), and free radical scavengers (DPPH and H2O2) in wheatgrass. Furthermore, the concentration of micronutrients (Zn and Fe), macronutrients (N, and P), and vitamins (B1 and E) also increased in the above treatment. Oxidative stress markers (malondialdehyde and electrolyte leakage) and Na+ accumulation were significantly reduced whilst K+ content increased in the shoot, which helped in maintaining the K+/Na+ ratio in wheatgrass under saline conditions. The results indicated that the application of ST-PGPR could not only reduce the dosage of mineral fertilizers but might be useful for improving the nutritional and antioxidant properties of medicinal crops such as wheatgrass under salt-stress conditions. Implementing this approach could result in the reduction of chemical usage, while also facilitating enhanced uptake of micronutrients in crops, particularly in regions affected by salinity.

Biological Characterization and Metabolic Variations among Cell-Free Supernatants Produced by Selected Plant-Based Lactic Acid Bacteria

The aim of this research was to assess the antibacterial and antioxidant properties as well as the variation in metabolites of the cell-free supernatant (CFS) produced by lactic acid bacteria (LAB) from local plants: Lactiplantibacillus plantarum ngue16, L. plantarum ng10, Enterococcus durans w3, and Levilactobacillus brevis w6. The tested strains exhibited inhibitory effects against pathogens, including Bacillus cereus, B. subtilis, Cronobacter sakazakii, Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus using the agar spot assay and well diffusion method. The CFS from all four strains displayed antibacterial activity against these pathogens with minimum inhibitory concentration (MIC) values ranging from 3.12 to 12.5 mg/mL and minimal bactericidal concentration (MBC) values ranging from 6.25 to 25.0 mg/mL. Moreover, the CFS demonstrated resilience within specific pH (3-8) and temperature (60-100 °C) ranges and lost its activity when treated with enzymes, such as Proteinase K and pepsin. Furthermore, the CFS exhibited antioxidant properties as evidenced by their ability to inhibit the formation of two radicals (1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) compared to the negative control, De Man, Rogosa, and Sharpe (MRS) broth. The use of proton-based nuclear magnetic resonance (¹H-NMR) spectroscopy revealed the presence and quantification of 48 metabolites in both the CFS and MRS broths. Principal Component Analysis (PCA) effectively differentiated between CFS and MRS broth by identifying the specific metabolites responsible for the observed differences. The partial least squares (PLS) model demonstrated a significant correlation between the metabolites in the LAB supernatant and the tested antibacterial and antioxidant activities. Notably, anserine, GABA, acetic acid, lactic acid, uracil, uridine, propylene glycol, isopropanol, serine, histidine, and indol-3-lactate were identified as the compounds contributing the most to the highest antibacterial and antioxidant activities in the supernatant. These findings suggest that the LAB strains investigated have the potential to be utilized in the production of functional foods and the development of pharmaceutical products.

Bioprospecting acid- and arsenic-tolerant plant growth-promoting rhizobacteria for mitigation of arsenic toxicity in acidic agricultural soils

Widespread use of chemical fertilizers and falling productivity in traditional agricultural practices has led to the biodiversity hotspot of North-Eastern region of India to face imminent threat to soil nutrients and biodiversity. The present work aimed to isolate rhizobacteria from Oryza sativa L. to evaluate their plant growth-promoting traits like indole, ammonia, siderophore production, and phosphate solubilization followed by in vitro plant growth promotion and anti-fungal assessment against Curvularia oryzae. Moreover, presence of heavy metals such as arsenic in chemical fertilizers and in groundwater contributes to arsenic contamination of agricultural soil. Taking this into consideration for the present study, the background metal content of the bulk soil, roots and grains of rice was measured. Arsenic tolerance of the rhizobacterial isolates was assessed using different concentrations of arsenite- and arsenate-supplemented media. 16S rRNA gene sequencing and phylogenetic tree analysis identified the isolates as Bacillus paramycoides, B. albus, B. altitudinis, B. koreensis, B. megaterium, B. wiedmannii, B. paramycoides, Chryseobacterium gleum, Stenotrophomonas maltophilia and Pseudomonas shirazica. Considering the acidic nature of the paddy growing soil, the growth kinetics of the isolates were monitored in acid and arsenic-supplemented conditions for 48 h of growth. Few isolates showed potent anti-fungal activity against the late blight phytopathogen, Curvularia oryzae MTCC 2605, apart from being potential growth promoters. The findings open vistas for the mass production of the characterized PGP rhizobacteria for their application in rehabilitation of the degrading arsenic contaminated paddy fields.

Bacillus subtilis isolates from camel milk as probiotic candidates

Recently Bacillus spp. has gained much attention as potential probiotics due to the production of resistant cells. So, this research is purposeful for evaluation of probiotic characteristics of Bacillus isolates from camel milk as a suitable source for growth and isolation of microorganisms that can be candidate to be used as probiotic. First, forty-eight colonies were screened by using morphological and biochemical analysis. Among the isolates, two of them were recognized as Bacillus subtilis CM1 and CM2 by partial 16SrRNA sequencing that, probiotic potentials of them were evaluated. Both of them, in the preliminary safety screening, were found negative for hemolysis and lecithinase activity. Also, in vitro characteristics such as acid, bile salts and artificial gastric juice resistant, cell surface hydrophobicity, auto-aggregation, antioxidant characteristics, and adherent capability to HT-29 cells were determined for them approximately in the range of other probiotic strains. Two strains were susceptible to various antibiotics and enterotoxigenic activities were not detected by PCR which means isolated Bacillus strains could be classified as safe. Altogether, results demonstrate that Bacillus CM1 and CM2 strains could have the potential of consideration as probiotics, however more extensive in vitro/vivo studies are needed.

Preliminary in vitro assessment of probiotic properties of Bacillus subtilis GM1, a spore forming bacteria isolated from goat milk

Background

Species of the Bacillus genus have a long history of use in biotechnology. Some Bacillus strains have recently been identified for food applications and industrial as safe bacteria, which mostly have been recognized as probiotic strains.

Aims

The primary purpose of the current study was to evaluate the probiotic characteristics of Bacillus subtilis strains isolated and identified from the goat milk samples.

Methods

After sampling from 40 goat milk and cultivation, suspected colonies were subjected to biochemical and molecular identification. Then, the confirmed isolate was assessed for in vitro probiotic tests, including hemolysis and lecithinase properties, bile salt, acid, and artificial gastric juice resistance, antioxidant activity, antibiotics susceptibility, enterotoxin genes detection, and attachment capacity to the HT-29 cells.

Results

Among 11 suspected isolates evaluated, only one isolate was identified as B. subtilis. In vitro tests for this strain showed similar results to other probiotic strains. The B. subtilis strain was susceptible to various antibiotics. The enterotoxin genes were not detected based on PCR assay. Concerning its probiotic characteristics assessment, especially tolerance to bile salts and acidic conditions, the Bacillus strain could have the potential to consider as a probiotic.

Conclusion

Goat milk can be recommended as a source of Bacillus isolates. Also, the isolated strain showed high adaptability to the gastrointestinal environment, relatively equal percentages of adhesion properties, and some safety aspects, having the potential to be considered as an appropriate probiotic.

Cross-Regulation between Autophagy and Apoptosis Induced by Vitamin E and Lactobacillus Plantarum through Beclin-1 Network

Autophagy and apoptosis are two important regulatory mechanisms for how the body can respond to diseases. This study was designed to investigate the protective actions of vitamin E (Vit-E) and lactobacillus plantarum (Lac-B) against mercuric chloride (HgCl₂)-induced kidney injury. Thirty albino rats were divided into five groups: group 1 served as the normal group; rats in group 2 received high doses of HgCl₂; rats in groups 3, 4 and 5 were given Vit-E, Lac-B and the combination of Vit-E and Lac-B, respectively along with HgCl₂ for two weeks. HgCl₂ provoked renal injury, manifested by elevation in serum urea, urea nitrogen and creatinine. Kidney levels of oxidative stress and inflammation were markedly increased post HgCl₂ administration. Moreover, HgCl₂ significantly elevated the gene expression levels of VCAM-1 and cystatin C, while podocin was downregulated. Additionally, it markedly decreased the protein expression of Beclin-1 and Bcl-2. Histopathological examination revealed massive degeneration with congested blood vessels following HgCl₂ administration. Treatment with Vit-E or/and Lac-B restored the normal levels of the previously mentioned parameters, as well as improved the morphology of kidney tissues. Both Vit-E and Lac-B provided a protective effect against HgCl₂-induced kidney damage by regulating autophagy and apoptosis.

Probiotic treatment of inflammatory bowel disease: Its extent and intensity

Free radicals (reactive oxygen species, superoxides and hydroxyl radicals) lead to the development of oxidative stress because of imbalance in the amount of antioxidants. Continued development of oxidative stress leads to chronic diseases in humans. The instability in the antioxidant activities and accumulation of oxidative stress due to free radicals may occur in diseases like inflammatory bowel disease (IBD). Antioxidants are substances that inhibit or delay the mechanism of oxidation of molecules mediated by free radicals and also transform into lesser-active derivatives. Probiotics are defined as live microorganisms that show beneficial effects on inflamed intestine and balance the inflammatory immune responses in the gut. Probiotic strains have been reported to scavenge hydroxyl radicals and superoxide anions that are abundantly produced during oxidative stress. The most widely studied probiotic strains are Streptococcus, Bifidobacterium and Lactobacillus. Probiotics cultured in broth have shown some amount of antioxidant activities. Fermented milk and soy milk, which possess starter microorganisms (probiotics), tends to increase the antioxidant activities many-fold. This review aims to discuss the in vivo and in vitro antioxidant activities of specific probiotics with various assays with respect to IBD.

In vitro assessment of the probiotic properties of an industrial preparation containing Lacticaseibacillus paracasei in the context of athlete health

Intense physical activity is often associated with undesirable physiological changes, including increased inflammation, transient immunodepression, increased susceptibility to infections, altered intestinal barrier integrity, and increased oxidative stress. Several trials suggested that probiotics supplementation may have beneficial effects on sport-associated gastro-intestinal and immune disorders. Recently, in a placebo-controlled human trial, the AminoAlta™ probiotic formulation (AApf) was demonstrated to increase the absorption of amino acids from pea protein, suggesting that the administration of AApf could overcome the compositional limitations of plant proteins. In this study, human cell line models were used to assess in vitro the potential capacity of AApf to protect from the physiological damages that an intense physical activity may cause. The obtained results revealed that the bacteria in the AApf have the ability to adhere to differentiated Caco-2 epithelial cell layer. In addition, the AApf was shown to reduce the activation of NF-κB in Caco-2 cells under inflammatory stimulation. Notably, this anti-inflammatory activity was enhanced in the presence of partially hydrolyzed plant proteins. The AApf also triggered the expression of cytokines by the THP-1 macrophage model in a dose-dependent manner. In particular, the expression of cytokines IL-1β, IL-6, and TNF-α was higher than that of the regulatory cytokine IL-10, resembling a cytokine profile characteristic of M1 phenotype, which typically intervene in counteracting bacterial and viral infections. Finally, AApf was shown to reduce transepithelial permeability and increase superoxide dismutase activity in the Caco-2 cell model. In conclusion, this study suggests that the AApf may potentially provide a spectrum of benefits useful to dampen the gastro-intestinal and immune detrimental consequences of an intense physical activity.

Functional Characteristics of Lactic Acid Bacteria In Vitro Isolated from Spontaneously Fermented Sour Porridge with Broomcorn Millet in Northwestern Shanxi Province of China

Eighteen strains of lactic acid bacteria were isolated from spontaneously fermented sour porridge with broomcorn millet in Northwestern Shanxi Province of China, and their probiotic characteristics were investigated in vitro. Survival rates under gastrointestinal conditions, cholesterol reduction, antibacterial capabilities, antioxidant activities, and safety assessments were examined. Results showed that five strains were selected as probiotics and identified as Levilactobacillusbrevis. Strain L10 exhibited excellent probiotic characteristics, with an 86% survival rate under pH 2.0 for 2 h, 80% survival rate in 0.3% bile salt for 6 h, the highest survival rate (78%) in simulated gastrointestinal juice for 3 h, the highest hydrophobicity (42% to xylene and 39% to hexadecane), the highest aggregation (39% auto-aggregation and 10.4–18.13% co-aggregation), relative higher cholesterol reduction rate (80%), the highest antibacterial activities, the highest antioxidant activity, sensitive to most antibiotics tested, without hemolytic and hydrolyze gelatinase activity and could not produce biogenic amine. Therefore, strain L10 could be applied to functional foods.

Genomics analysis of Lactobacillus paracasei SLP16

Lactobacillus paracasei SLP 16 was obtained from liquor cellar mud, and it was analyzed by genome sequencing on Illumina Hiseqq platfrom. Then the biological information of Lactobacillus paracasei SLP16 was analyzed by ExPasy (wedsite), and the toxin safety of the strian SLP 16 was analyzed by PSI/PHI in the virulence factor database VFDB. Through the second-generation DNA sequencing platform technology, the whole genome information of Lactobacillus paracasei SLP16 was obtained, which showed that the genome size of the strian SLP 16 was 2.65M, and the GC content of the strian SLP 16 was 46.9%. And a total of 3,131 genes were detected, including 3,067 genes encoding protein and 63 genes encoding RNA. Whole genome analysis showed that Lactobacillus paracasei SLP16 had 5 coding genes of F₀ F₁ -ATPase, 4 coding genes of Na⁺ /H⁺ antiporter and 3 coding genes of A-ATPase, which were closely related to the acid tolerance of lactic acid bacteria (LAB). Whole genome analysis of Lactobacillus paracasei SLP16 showed that SLP 16 had only one CFA synthetic coding gene, and no important BSH coding gene, however, it had F₀ F₁ -ATPase, Na⁺ /H⁺ antiporter and several two-component regulatory systems, and which were related to bile salt tolerance of LAB. Safety evaluation in Lactobacillus paracasei SLP16 showed that it did not have the virulence factor coding gene related to toxin. Common antibiotic sensitivity tests showed that Lactobacillus paracasei SLP16 was resistant to compound sulfamethoxazole, ciprofloxacin, gentamicin and lincomycin. In summary, Lactobacillus paracasei SLP16 had coding genes closely related to acid tolerance and bile salt tolerance, and no coding gene of virulence factors related to toxins, and few kinds of resistant antibiotics. Therefore, whole genome analysis showed that Lactobacillus paracasei SLP16 was a safe probiotic strain that can be safely applied.

Ecofriendly green biosynthesis and characterization of novel bacteriocin-loaded bacterial cellulose nanofiber from Gluconobacter cerinus HDX-1

A new strain of bacterial cellulose (BC)-producing Gluconobacter cerinus HDX-1 was isolated and identified, and a simple, low-cost complexation method was used to biosynthesis Lactobacillus paracasei 1∙7 bacteriocin BC (BC-B) nanofiber. The structure and antibacterial properties of the nanofibers were evaluated. Solid-state nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR) and x-ray diffraction (XRD) analysis showed that BC and BC-B nanofibers had typical crystalline form of the cellulose I. X-ray photoelectron spectrometer (XPS), scanning electron microscope (SEM) and atomic force microscopy (AFM) revealed that the bacteriocin and BC were successfully compounded, and the structure of BC-B nanofiber was tighter than BC nanofiber, with lower porosity, swelling ratio and water vapor transmission rate (WVTR). The tensile strength and Young's modulus of BC-B nanofibers were 13.28 ± 1.26 MPa and 132.10 ± 4.92 MPa, respectively, higher than that of BC nanofiber (6.12 ± 0.87 MPa and 101.59 ± 5.87 MPa), indicating that bacteriocin enhance the mechanical properties of BC nanofiber. Furthermore, the BC-B nanofibers exhibited significant thermal stability, antioxidant capacity and antibacterial activity than BC nanofiber. Therefore, bacteriocin-loaded BC nanofiber may be used as antimicrobial agents in active food packaging and medical material.

The impacts of antimicrobial and antifungal activity of cell-free supernatants from lactic acid bacteria in vitro and foods

Lactic acid bacteria (LAB) are distinguished by their ability to produce lactic acid, among other interesting metabolites with antimicrobial activity. A cell-free supernatant (CFS) is a liquid containing the metabolites resulting from microbial growth and the residual nutrients of the medium used. CFS from LAB can have antimicrobial activity due to organic acids, fatty acids, and proteinaceous compounds, among other compounds. This review aims to summarize the information about CFS production, CFS composition, and the antimicrobial (antibacterial and antifungal) activity of CFS from LAB in vitro, on foods, and in active packaging. In addition, the mechanisms of action of CFS on cells, the stability of CFS during storage, CFS cytotoxicity, and the safety of CFS are reviewed. The main findings are that CFS's antibacterial and antifungal activity in vitro has been widely studied, particularly in members of the genus Lactobacillus. CFS has produced strong inhibition of bacteria and molds on foods when applied directly or in active packaging. In most studies, the compounds responsible for antimicrobial activity are identified. A few studies indicate that CFSs are stable for 1 to 5 months at temperatures ranging from 4 to 35°C. The cytotoxicity of CFS on human cells has not been well studied. However, the studies that have been performed reported no toxicity of CFS. Therefore, it is necessary to investigate novel growth mediums for CFS preparation that are compatible with food sensory properties. More studies into CFS stability and cytotoxic effects are also needed.

Development of Anti-inflammatory Probiotic Limosilactobacillus reuteri EFEL6901 as Kimchi Starter: in vitro and In vivo Evidence

The use of probiotic starters can improve the sensory and health-promoting properties of fermented foods. In this study, we developed an anti-inflammatory probiotic starter, Limosilactobacillus reuteri EFEL6901, for use in kimchi fermentation. The EFEL6901 strain was safe for use in foods and was stable under human gastrointestinal conditions. In in vitro experiments, EFEL6901 cells adhered well to colonic epithelial cells and decreased nitric oxide production in lipopolysaccharide-induced macrophages. In in vivo experiments, oral administration of EFEL6901 to DSS-induced colitis mice models significantly alleviated the observed colitis symptoms, prevented body weight loss, lowered the disease activity index score, and prevented colon length shortening. Analysis of these results indicated that EFEL6901 played a probiotic role by preventing the overproduction of pro-inflammatory cytokines, improving gut barrier function, and up-regulating the concentrations of short-chain fatty acids. In addition, EFEL6901 made a fast growth in a simulated kimchi juice and it synthesized similar amounts of metabolites in nabak-kimchi comparable to a commercial kimchi. This study demonstrates that EFEL6901 can be used as a suitable kimchi starter to promote gut health and product quality.

Immunomodulatory Effect of Bifidobacterium, Lactobacillus, and Streptococcus Strains of Paraprobiotics in Lipopolysaccharide-Stimulated Inflammatory Responses in RAW-264.7 Macrophages

The discovery of the potential of paraprobiotics to exert different immunological benefits suggests that further studies should be carried out to determine their potential and mechanisms of action in modulating the immune system. The objective of this study was to investigate the immune response of several microbial-associated molecular patterns (MAMPS) used at different doses in macrophage cell lines RAW-264.7 stimulated with lipopolysaccharide (LPS). Two experiments were conducted. The first was performed to determine a dose response curve for each paraprobiotic (Bifidobacterium lactis, Lactobacillus casei, Lactobacillus gasseri, Lactobacillus paracasei, and Streptococcus thermophilus). Further experiments were carried using only two doses (0.01 g/ml and 0.1 g/ml). RAW-264.7 cells were cultivated in Dubelcco's Modified Eagle's medium supplemented with fetal bovine serum and penicillin/streptomycin. Cells were incubated with LPS (1 μg/ml) and six concentrations of MAMPs were added. RAW-264.7 viability, myeloperoxidase activity, nitrite/nitrate concentration, reactive oxygen species production, oxidative damage, and inflammatory parameters were measured. In the LPS group, there was a significant reduction in cell viability. Myeloperoxidase and nitrite/nitrate concentrations demonstrated a better effect at 0.01 and 0.1 g/ml doses. There was a significant reduction in interleukin-6 (IL-6) levels at 0.1 g/ml dose in all paraprobiotics. IL-10 levels decreased in the LPS group and increased at 0.1 g/ml dose in all paraprobiotics. The dichlorofluorescin diacetate results were reinforced by the observed in oxidative damage. Paraprobiotics are likely to contribute to the improvement of intestinal homeostasis, immunomodulation, and host metabolism.

Unraveling the probiotic efficiency of bacterium Pediococcus pentosaceus OBK05 isolated from buttermilk: An in vitro study for cholesterol assimilation potential and antibiotic resistance status

The present study describes the probiotic potential and functional properties of the lactic acid bacterium Pediococcus pentosaceus OBK05 isolated from buttermilk. The isolate OBK05 was assessed for its probiotic properties. The isolate showed notable tolerance to pH 2.0 and 3.0 (8.44, 8.35 log CFU/mL), oxbile of 0.5% at 2 and 4 h of incubation (6.97, 6.35 log CFU/mL) and higher aggregation (auto-aggregation, adhesion to hydrocarbons) than the referral strain, Lactobacillus acidophilus MTCC 10307. The adhesion efficiency to HT-29 cells was found to be maximum, corresponding to 93.5% and 97% at 1 and 2 h incubation, respectively. In addition, the isolate OBK05 showed antagonistic solid activity against bacterial pathogens like Pseudomonas aeruginosa MTCC 424 and Bacillus subtilis MTCC 1133. The phenotypic antibiotic resistance of the isolate was examined before and after curing plasmids. Among the known five structural genes responsible for different antibiotic resistance, four genes indicating antibiotic resistance to kanamycin-Aph (3´´)-III, streptomycin-strA, vancomycin-vanA and ciprofloxacin-gyrA were detected by PCR amplification of genomic DNA. Further, the horizontal gene transfer from OBK05 isolate to pathogens was not found for these antibiotic resistance markers when filter and food mating were carried out as no transconjugants developed on media plates containing respective antibiotics. This indicates that the intrinsic resistance is harbored on chromosomal genes, and hence it is nontransferable to other microbes. In addition, strain OBK05 exhibited good DPPH scavenging activity of 56 to 77% and liberated free amino acid from conjugated bile acid. The strain OBK05 demonstrated a strong ability to reduce cholesterol at 12 h (17%), 24 h (27%) and 48 h (67%) of incubation.

In vitro bioactivities of coffee brews fermented with the probiotics Lacticaseibacillus rhamnosus GG and Saccharomyces boulardii CNCM-I745

Previously, we demonstrated the production of bioactive metabolites (e.g., indole-3-lactate, 4-hydroxyphenyllactate, 3-phenyllactate, 2-isopropylmalate) by the probiotics Lacticaseibacillus rhamnosus GG and Saccharomyces boulardii CNCM-I745 during coffee brew fermentation. However, it remains unclear if in situ production of bioactive metabolites confers additional health benefits to coffee brews. Here, we aimed to investigate the in vitro bioactivities of freeze-dried cell-free coffee supernatants fermented with L. rhamnosus GG and/or S. boulardii CNCM-I745, compared to non-fermented coffee supernatants. In vitro bioactivity assays pertained to α-amylase and α-glucosidase inhibition, antiglycative activities, anti-proliferation against human cancer cell lines (MCF-7, HCT116, and HepG2), cellular antioxidant activities, and anti-inflammatory activities. We demonstrated that non-fermented coffee supernatants displayed weak starch hydrolase inhibition (IC₅₀ > 36.00 mg/mL), but otherwise displayed strong anti-glycative (IC₅₀ 0.71-0.74 mg/mL), anti-proliferative (IC₅₀ 0.45, 0.36, and < 0.5 mg/mL for MCF-7, HCT116, and HepG2 respectively), cellular antioxidant (85,844.22 µmol quercetin equivalents/100 g coffee supernatant), and anti-inflammatory activities (35.7% reduction in nitrite production at 0.13 mg/mL). In all the assays tested, probiotic fermented coffee supernatants exhibited very similar bioactivities compared to non-fermented coffee supernatants, and improvements were not observed. Overall, in vitro bioactivities of coffee brews were not improved via in situ metabolite production by L. rhamnosus GG and/or S. boulardii CNCM-I745. Therefore, bioactive metabolites produced during probiotic-induced food fermentations may not necessarily confer additional health benefits compared to non-fermented counterparts.

Kombucha Tea-A Double Power of Bioactive Compounds from Tea and Symbiotic Culture of Bacteria and Yeasts (SCOBY)

Kombucha is a low alcoholic beverage with high content of bioactive compounds derived from plant material (tea, juices, herb extracts) and metabolic activity of microorganisms (acetic acid bacteria, lactic acid bacteria and yeasts). Currently, it attracts an increasing number of consumers due to its health-promoting properties. This review focuses on aspects significantly affecting the bioactive compound content and biological activities of Kombucha tea. The literature review shows that the drink is characterized by a high content of bioactive compounds, strong antioxidant, and antimicrobial properties. Factors that substantially affect these activities are the tea type and its brewing parameters, the composition of the SCOBY, as well as the fermentation parameters. On the other hand, Kombucha fermentation is characterized by many unknowns, which result, inter alia, from different methods of tea extraction, diverse, often undefined compositions of microorganisms used in the fermentation, as well as the lack of clearly defined effects of microorganisms on bioactive compounds contained in tea, and therefore the health-promoting properties of the final product. The article indicates the shortcomings in the current research in the field of Kombucha, as well as future perspectives on improving the health-promoting activities of this fermented drink.

Phytochemicals and Immunomodulatory Effect of Nelumbo nucifera Flower Extracts on Human Macrophages

This research characterizes phytochemicals inherent in lotus flower and investigates the antioxidant and immunomodulatory activity of ethyl acetate (EA) and ethyl alcohol (ET) lotus petal extracts. In the experiment, human monocytes-derived macrophages were stimulated by lipopoly-saccharide to mimic bacteria-induced inflammation. The results showed that ferulic acid, couma-rin, and chlorogenic acid were three dominant polyphenols. The EA and ET lotus petal extracts also possessed high antioxidant capability. Furthermore, the extracts exhibited immunomodulatory properties by suppressing TNF-α secretion in inflammatory-induced human macrophages by in-hibiting NF-κB-dependent inflammatory response. In essence, the lotus petal extracts possess reme-dial attributes beneficial to individuals afflicted with declined immune functions.

Gastrointestinal transit tolerance, cell surface hydrophobicity, and functional attributes of Lactobacillus Acidophilus strains isolated from Indigenous Dahi

Strains of Lactobacillus acidophilus WFA1 (KU877440), WFA2 (KU877441), and WFA3 (KU877442) were isolated from indigenous Dahi (yogurt), screened, and selected based on acid and bile tolerance along with the antimicrobial activity. These selected strains were further assessed for their probiotic and functional attributes. Results for simulated gastric and intestinal tolerance/ resistance revealed that all three strains can resist and survive under the following mentioned conditions. To access cell surface hydrophobicity, bacterial adhesion to hydrocarbons (BATH), cellular auto-aggregation, and salt aggregation were performed. In BATH, adhesion of strains against three hydrocarbons namely xylene, dichloromethane, and hexadecane was conducted. The results show that strains showed the least adhesion to xylene (54.25%) as compared to dichloromethane (55.25%) and hexadecane (56.65%). WFA1 showed maximum adherence percentage (55.48%) followed WFA2 (55.48%) and WFA3 (51.38%). Cellular auto-aggregation varied from 21.72% to 30.73% for WFA3 and WFA1, respectively. In the salt aggregation test (SAT), WFA1, WFA2, and WFA3 aggregated at 0.6, 1.0, and 2.0 molar concentrations of ammonium sulfate, respectively. PCR amplification of bile salt hydrolase gene (bsh) was performed and sequences were submitted to the public database of NCBI and Gene bank under accession numbers, KY689139, KY689140, and KY689141. Additionally, a cholesterol-lowering assay was conducted and up to 26% reduction in cholesterol was observed by the strains. Regarding functional properties, exopolysaccharide (EPS) production, and antioxidant potential, strain WFA1 showed promising results EPS (1.027mg/ml), DPPH (80.66%), ABTS (81.97%), and reducing power (1.787). It can be concluded from the present study that the mentioned strains of L. acidophilus (WFA1, WFA2, and WFA3) are strongly hydrophobic; thus having an ability to survive and colonize under the gastrointestinal tract which confirms their probiotic nature. Regarding their functional properties, L. acidophilus WFA1 (KU877440) showed excellent properties of antioxidants and EPS production.

In Silico Prediction and In Vitro Assessment of Multifunctional Properties of Postbiotics Obtained From Two Probiotic Bacteria

In this study, a global metabolite profile using Raman spectroscopy analysis was obtained in order to predict, by an in silico prediction of activity spectra for substance approach, the bioactivities of the intracellular content (IC) and cell wall (CW) fractions obtained from Lactobacillus casei CRL 431 and Bacillus coagulans GBI-30 strains. Additionally, multifunctional in vitro bioactivity of IC and CW fractions was also assessed. The metabolite profile revealed a variety of compounds (fatty acids, amino acids, coenzyme, protein, amino sugars), with significant probable activities (Pa > 0.7) as immune-stimulant, anti-inflammatory, neuroprotective, antiproliferative, immunomodulator, and antineoplastic, among others. Moreover, in vitro assays exhibited that both IC and CW fractions presented angiotensin-converting enzyme-inhibitory (> 90%), chelating (> 79%), and antioxidant (ca. 22-57 cellular antioxidant activity units) activities. Our findings based on in silico and in vitro analyses suggest that L. casei CRL 431 and B. coagulans GBI-30 strains appear to be promising sources of postbiotics and may impart health benefits by their multifunctional properties.

Bioprospecting of Palmyra Palm (Borassus flabellifer) Nectar: Unveiling the Probiotic and Therapeutic Potential of the Traditional Rural Drink

The present study investigates the therapeutic and probiotic attributes of traditional Toddy Palm Nectar (TPN). Glucose was found to be the highest with 4.37 mg/ml and arabinose was the least with 2.85 mg/ml. The average ethanol concentration of fresh TPN was found to be 0.3 mg/ml. The nutritional profile of TPN revealed 18 volatile fatty acids, the major one being hexadecenoic acid (M/Z 74). Amino acid profiling showed 26 amino acids, with OH-lysine-2 the highest (12.86%). About 120 morphologically distinct lactic acid bacteria (LAB) were isolated from 26 TPN samples, based on differential growth and in vitro probiotic characteristics. After 16S rRNA sequencing, four indigenous LAB strains were identified as Lactobacillus plantarum group OUBN1, Enterococcus faecium OUBN3, Pediococcus acidilactici OUBN4, and Pediococcus pentosaceous OUBN5 and their sequences were deposited to NCBI. Microbiological safety evaluation studies showed the absence of hemolytic, gelatinolytic and proteolytic activity. The bacterial isolate OUBN3 showed a maximum survival rate of 6.91 ± 0.04 log cfu/ml at acidic pH 2.5 and isolate OUBN5 showed 6.94 ± 0.02 log cfu/ml at pH 3.0. Similarly, the isolate OUBN5 showed 7.92 ± 0.03 log cfu/ml to 0.3% ox-bile after 4 h and 8.94 ± 0.03 log cfu/ml to simulated gastric juice after 3 h of treatments. OUBN1 expressed the highest autoaggregation (81.76 ± 1.25%), cell surface hydrophobicity (79.71 ± 3.42%), and displayed the maximum coaggregation with E. coli MTCC452 (76.96%), K. pneumoniae MTCC109 (75.62%), and S. aureus MTCC902 (70.69%). All strains showed significant antibiotic and antimicrobial activity. Isolate OUBN1 displayed hydroxyl radical scavenging activity (68.71 ± 1.0%) with an IC₅₀ value of 75.62 μg/ml and the highest anti-cancer activity (percentage inhibition of 88.55) against HT-29 cells. Based on the characteristics observed, L. plantarum group OUBN1 and P. pentosaceous OUBN5 were found to be potential isolates to employ as probiotic microbiota in food and forage preparations. These findings reinforce the fact that LAB isolated from TPN could be exploited as an alternative means toward potential therapeutic applications.

Selected Kefir Water from Malaysia Attenuates Hydrogen Peroxide-Induced Oxidative Stress by Upregulating Endogenous Antioxidant Levels in SH-SY5Y Neuroblastoma Cells

Kefir, a fermented probiotic drink was tested for its potential anti-oxidative, anti-apoptotic, and neuroprotective effects to attenuate cellular oxidative stress on human SH-SY5Y neuroblastoma cells. Here, the antioxidant potentials of the six different kefir water samples were analysed by total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH) assays, whereas the anti-apoptotic activity on hydrogen peroxide (H₂O₂) induced SH-SY5Y cells was examined using MTT, AO/PI double staining, and PI/Annexin V-FITC assays. The surface and internal morphological features of SH-SY5Y cells were studied using scanning and transmission electron microscopy. The results indicate that Kefir B showed the higher TPC (1.96 ± 0.54 µg GAE/µL), TFC (1.09 ± 0.02 µg CAT eq/µL), FRAP (19.68 ± 0.11 mM FRAP eq/50 µL), and DPPH (0.45 ± 0.06 mg/mL) activities compared to the other kefir samples. The MTT and PI/Annexin V-FITC assays showed that Kefir B pre-treatment at 10 mg/mL for 48 h resulted in greater cytoprotection (97.04%), and a significantly lower percentage of necrotic cells (7.79%), respectively. The Kefir B pre-treatment also resulted in greater protection to cytoplasmic and cytoskeleton inclusion, along with the conservation of the surface morphological features and the overall integrity of SH-SY5Y cells. Our findings indicate that the anti-oxidative, anti-apoptosis, and neuroprotective effects of kefir were mediated via the upregulation of SOD and catalase, as well as the modulation of apoptotic genes (Tp73, Bax, and Bcl-2).

Optimising the DPPH Assay for Cell-Free Marine Microorganism Supernatants

Antioxidants prevent ageing and are usually quantified and screened using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. However, this assay cannot be used for salt-containing samples, such as the cell-free supernatants of marine microorganisms that are aggregated under these conditions. Herein, the DPPH solvent (methanol or ethanol) and its water content were optimized to enable the analysis of salt-containing samples, aggregation was observed for alcohol contents of >70%. The water content of methanol influenced the activities of standard antioxidants but did not significantly affect that of the samples. Based on solution stability considerations, 70% aqueous methanol was chosen as the optimal DPPH solvent. The developed method was successfully applied to the cell-free supernatants of marine bacteria (Pseudoalteromonas rubra and Pseudoalteromonas xiamenensis), revealing their high antioxidant activities. Furthermore, it was concluded that this method would be useful for the screening of marine microorganism-derived antioxidants, which also has numerous potential applications, such as salt-fermented foods.

Deciphering the Probiotic Potential of Bacillus amyloliquefaciens COFCAU_P1 Isolated from the Intestine of Labeo rohita Through In Vitro and Genetic Assessment

In this study, a bacterial strain COFCAU_P1, isolated from the digestive tract of a freshwater teleost rohu (Labeo rohita), was identified as Bacillus amyloliquefaciens using 16S rRNA gene sequence analysis combined with amplification of species-specific BamHI and barnase genes. The probiotic potential of the strain was evaluated using an array of in vitro tests along with safety and genetic analyses. The isolate showed potent antimicrobial response against several fish pathogenic bacteria, survived a wide pH range (2-9), and was resistant up to 10% bile salt concentration. With regard to the in vitro adhesion properties, the strain showed significantly high in vitro adhesion to mucus, auto and co-aggregation capacity, and cell surface hydrophobicity. The strain was non-haemolytic, able to produce extracellular enzymes, viz., proteinase, amylase, lipase, and cellulase, and showed significant free radical scavenging activity. A challenge study in rohu revealed the strain COFCAU_P1 as non-pathogenic. The presence of putative probiotic marker genes including 2, 3-bisphosphoglycerate-independent phosphoglycerate mutase, arginine/ornithine antiporter ArcD, choloylglycine hydrolase, LuxS, and E1 β-subunit of the pyruvate dehydrogenase complex was confirmed by PCR, suggesting the molecular basis of the probiotic-specific functional attributes of the isolate. In conclusion, the in vitro and genetic approaches enabled the identification of a potential probiotic from autochthonous source with a potential of its utilization in the aquaculture industry.

Effects of potential synbiotic interaction between Lactobacillus rhamnosus GG and salicylic acid on human colon and prostate cancer cells

Salicylic acid, widely distributed in the whole plant kingdom, is a benzoic acid derivative acting as a signal substance in plants, but could be related to differences in cancer incidence, as many herbs and spices contain high amounts. Lactobacillus rhamnosus GG (LGG) is one of the best-known lactic acid bacteria that has been studied for over 30 years. Probiotic and/or commensal bacteria of the human microbiota are known to respond to diet constituents. Therefore, the present study aims at investigating the possible effects of salicylic acid on the probiotic properties of LGG, and in vitro cytotoxic effects of combination of salicylic acid and LGG on human colon and prostate cancer cells. Salicylic acid significantly (p < 0.05) increased co-aggregation of LGG with E. coli (~ twofold) and anti-oxidant properties. Furthermore, it also induced the cytotoxic effects of LGG against human colon cancer cells. These results suggest that interaction of LGG with salicylic acid can exert more probiotic properties.

Comparative Studies of Inhibitory and Antioxidant Activities, and Organic Acids Compositions of Postbiotics Produced by Probiotic Lactiplantibacillus plantarum Strains Isolated From Malaysian Foods

Despite inflammation being a protective natural defense against imbalance stressors in the body, chronic inflammation could lead to the deterioration of immune response, low production, and poor performance in livestock as well as severe economic losses to the farmers. Postbiotics produced by Lactiplantibacillus plantarum has been reported recently to be a natural source of antioxidant, promoting growth performance, anti-inflammation, and immune responses. However, the effects of fermentation media on the compositions of L. plantarum postbiotic have not been reported elsewhere. Hence, a comparative study was conducted to compare the volatile compounds, organic acid composition, and antioxidant and antimicrobial activities of postbiotics produced by six strains of L. plantarum cultivated by using formulated media and the commercial de Man, Rogosa, and Sharpe (MRS) medium as a control. Postbiotics RG14, RI11, and UL4 produced by using formulated media exhibited higher inhibitory activity against Pediococcus acidilactici 446, Escherichia coli E-30, Salmonella enterica CS3, and vancomycin-resistant Enterococci except for Listeria monocytogenes LS55. As for the antioxidant activity, hydroxyl radical scavenging activity was enhanced in formulated media, whereas reducing power activity was the highest in postbiotic RI11. Three organic acids, namely, acetic acid, caproic acid, and lactic acid, were detected in the postbiotic produced by various L. plantarum strains. The concentration of acetic acid was influenced by the fermentation media, whereas caproic acid was detected as the highest in postbiotic RG11. Lactic acid was the predominant compound detected in all the postbiotics and had the significantly highest concentration in postbiotic RS5 when produced by using the MRS medium. Intermediary and pyrrole compounds were the other main compounds that were detected by using GC-MS. Positive correlations were found between organic acid production and inhibitory activity, as well as antioxidant activity exhibited by postbiotics. In conclusion, the compositions and functional characteristics of postbiotics produced by the six strains of L. plantarum were strain-dependent and affected greatly by the fermentation medium. The effects of postbiotic composition on the functional characteristics of postbiotics were elucidated in this study to warrant their applications as a promising beneficial natural growth promoter for the livestock industry.

Lipolytic Postbiotic from Lactobacillus paracasei Manages Metabolic Syndrome in Albino Wistar Rats

The current study investigates the capacity of a lipolytic Lactobacillus paracasei postbiotic as a possible regulator for lipid metabolism by targeting metabolic syndrome as a possibly safer anti-obesity and Anti-dyslipidemia agent replacing atorvastatin (ATOR) and other drugs with proven or suspected health hazards. The high DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2'-azino-bis (3-ethyl benzothiazoline-6-sulphonic acid)] scavenging activity and high activities of antioxidant enzyme such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-px) of the Lactobacillus paracasei postbiotic (cell-free extract), coupled with considerable lipolytic activity, may support its action against metabolic syndrome. Lactobacillus paracasei isolate was obtained from an Egyptian cheese sample, identified and used for preparing the postbiotic. The postbiotic was characterized and administered to high-fat diet (HFD) albino rats (100 and 200 mg kg^-1) for nine weeks, as compared to atorvastatin (ATOR; 10 mg kg^-1). The postbiotic could correct the disruption in lipid metabolism and antioxidant enzymes in HFD rats more effectively than ATOR. The two levels of the postbiotic (100 and 200 mg kg^-1) reduced total serum lipids by 29% and 34% and serum triglyceride by 32-45% of the positive control level, compared to only 25% and 35% in ATOR's case, respectively. Both ATOR and the postbiotic (200 mg kg^-1) equally decreased total serum cholesterol by about 40% and 39%, while equally raising HDL levels by 28% and 30% of the positive control. The postbiotic counteracted HFD-induced body weight increases more effectively than ATOR without affecting liver and kidney functions or liver histopathology, at the optimal dose of each. The postbiotic is a safer substitute for ATOR in treating metabolic syndrome.

Identification of a Transcriptomic Network Underlying the Wrinkly and Smooth Phenotypes of Vibrio fischeri

Vibrio fischeri is a cosmopolitan marine bacterium that oftentimes displays different colony morphologies, switching from a smooth to a wrinkly phenotype in order to adapt to changes in the environment. This wrinkly phenotype has also been associated with increased biofilm formation, an essential characteristic for V. fischeri to adhere to substrates, to suspended debris, and within the light organs of sepiolid squids. Elevated levels of biofilm formation are correlated with increased microbial survival of exposure to environmental stressors and the ability to expand niche breadth. Since V. fischeri has a biphasic life history strategy between its free-living and symbiotic states, we were interested in whether the wrinkly morphotype demonstrated differences in its expression profile in comparison to the naturally occurring and more common smooth variant. We show that genes involved in major biochemical cascades, including those involved in protein sorting, oxidative stress, and membrane transport, play a role in the wrinkly phenotype. Interestingly, only a few unique genes are specifically involved in macromolecule biosynthesis in the wrinkly phenotype, which underlies the importance of other pathways utilized for adaptation under the conditions in which Vibrio bacteria are producing this change in phenotype. These results provide the first comprehensive analysis of the complex form of genetic activation that underlies the diversity in morphologies of V. fischeri when switching between two different colony morphotypes, each representing a unique biofilm ecotype.IMPORTANCE The wrinkly bacterial colony phenotype has been associated with increased squid host colonization in V. fischeri The significance of our research is in identifying the genetic mechanisms that are responsible for heightened biofilm formation in V. fischeri This report also advances our understanding of gene regulation in V. fischeri and brings to the forefront a number of previously overlooked genetic networks. Several loci that were identified in this study were not previously known to be associated with biofilm formation in V. fischeri.

Lactobacillus spp. reduces ethanol-induced liver oxidative stress and inflammation in a mouse model of alcoholic steatohepatitis

Alcoholic steatohepatitis (ASH) is a complex multifactorial disease that can lead to liver fibrosis and cirrhosis if not treated promptly. Alcohol-induced oxidative stress and inflammation are the main factors that cause steatohepatitis and liver injury; however, probiotic bacteria in the gastrointestinal tract have been revealed to regulate immune responses and reduce oxidative stress, suggesting that functional probiotics could help to prevent ASH and liver injury. Despite numerous reports on the interactions between ASH and probiotics, the mechanisms underlying probiotic-mediated liver protection remain unknown. Therefore, the aim of the present study was to screen probiotics with high antioxidant capacity and investigate the ability of different probiotic combinations to reduce alcoholic liver disease (ALD) in a mouse model. It was identified that Lactobacillus plantarum (TSP05), Lactobacillus fermentum (TSF331) and Lactobacillus reuteri (TSR332) neutralized free radicals and displayed high antioxidant activity in vitro. In addition, these three functional probiotic strains protected mice from alcohol-induced liver injury in vivo. Mice treated with the probiotics demonstrated significantly lower alanine aminotransferase, aspartate aminotransferase and triglyceride levels, which were associated with the downregulation of the proinflammatory cytokines TNF-α and IL-6. Furthermore, probiotic treatment upregulated glutathione and glutathione peroxidase activity, which are bioindicators of oxidative stress in the liver. Collectively, the present results indicated that Lactobacillus strains TSP05, TSF331 and TSR332 reduced oxidative stress and inflammatory responses, thus preventing ASH development and liver injury.

Diabetes mellitus and congestive heart failure: the prevalence of congestive heart failure in patients with and without diabetes in Poland

INTRODUCTION

Diabetes mellitus is a systemic disease and has a negative effect on the cardiovascular system. This paper aimed to present a retrospective analysis of morbidity associated with heart failure in subgroups of patients with and without diabetes in Poland in 2012.

MATERIAL AND METHODS

Data from the National Health Fund were used for the study. In general, 656,937 patients with heart failure, including 281,538 males and 375,354 females, were studied. In this population, additionally, 201,043 patients with heart failure (main diagnosis) and diabetes were studied, including 82,117 males and 118,926 females.

RESULTS

The mean index of morbidity associated with heart failure in the whole subpopulation of diabetes patients was 9.03%; 8.42% for males and 9.50% for females. Morbidity associated with heart failure in the population of patients diagnosed with diabetes in Poland in 2012 was seven times higher compared to morbidity associated with heart failure in non-diabetes patients. Morbidity associated with heart failure in females was significantly higher compared to morbidity in males in the whole population, in both the subpopulations of patients with and without diabetes.

CONCLUSIONS

Diabetes mellitus significantly increases risk of heart failure in both women and men. The risk is significantly high after the age of 60 years and higher in females.

Evaluation of nutraceutical application of xylooligosaccharide enzymatically produced from cauliflower stalk for its value addition through a sustainable approach

There is increasing attention on the exploration of waste feedstocks as economically viable substrates for the production of prebiotic oligosaccharides, especially xylooligosaccharides, as excellent candidates for the maintenance and promotion of gut microbiota. XOS, an emerging prebiotic that has several functional attributes and beneficial health effects, is mainly produced by different processes, especially enzymatic hydrolysis through the valorisation of xylan enriched lignocellulosic materials. The present study deals with the enzymatic production of xylooligosaccharide (XOS) from xylan rich cauliflower stalk, a novel source. Delignification with alkali (NaOH) was found to be more efficient than acid and autohydrolysis, resulting in a higher extraction yield of xylan (18.42%). Alkaline extraction for 120 minutes at 1.25 M alkali concentration produced maximum xylan yield. FTIR analysis of xylan extracted from cauliflower stalk by an alkaline (NaOH) pretreatment method showed typical absorption bands at 1729 cm-1 that correspond to acetyl groups exhibiting the typical xylan specific band. Enzymatic hydrolysis was carried out with indigenously produced crude endoxylanase obtained from Aspergillus niger MTCC 9687 and the effects of substrate concentration, enzyme concentration, pH, time and temperature were investigated. High resolution MS analysis showed the presence of xylobiose as the major XOS. The major 1H spectral signals of XOS liberated from enzymatically hydrolysed alkali extracted cauliflower stalk xylan showed the presence of β-anomeric protons in the spectral region of 4.0-4.7 ppm. Prebiotic efficacy of cauliflower stalk derived XOS alone and synbiotic combinations with known probiotic strains (Lactiplantibacillus plantarum, Bifidobacterium bifidum, Lactobacillus delbrueckii ssp. Helveticus) were evaluated. Butyrate was found to be the major short chain fatty acid produced by XOS supplemented fermentation media. All the synbiotic combinations showed significantly higher antioxidant and antimicrobial activities and reduced the viability of human bone cancer MG-63 cells. The individual profiles of antimicrobial components of XOS were identified as dihydroxy benzoic acid and aspartic acid by HPLC coupled to a photodiode array detector.

Pseudomonas entomophila PE3 and its exopolysaccharides as biostimulants for enhancing growth, yield and tolerance responses of sunflower under saline conditions

Evaluation of plant growth promoting bacteria and the associated metabolites under saline conditions can be a potential eco-friendly remediation and productivity enhancement strategy. Salt-tolerant Pseudomonas entomophila PE3 was isolated from saline soil and screened for plant growth promoting (PGP) traits. The isolate produced indole acetic acid (IAA), gibberellic acid (GA), exopolysaccharides (EPS) and siderophore along with the potential to solubilize potassium (K), zinc (Zn) and phosphorus (P). Maximum stimulation of PGP attributes was recorded at 2% NaCl concentration. To determine the role of EPS, their composition was analyzed (at different salt concentrations) and comparison was done to determine the changes upon exposure to salinity. EPS was found to be rich in carbohydrates, proteins and phenolic compounds. The extracted EPS were also found to possess salt-tolerance properties including antioxidant, hydroxyl scavenging activity, reducing power, emulsification and flocculation potential, and Na⁺ accumulation ability. Interestingly, the salt tolerance properties of EPS were enhanced upon exposure to salinity (2% NaCl). Finally, EPS based bioformulation of isolate PE3 was checked through field assay in saline soil. With promising results on growth promotion and improved salinity tolerance attributes of inoculated sunflower plants, the bioformulation of PE3 amended with EPS can be a breakthrough for remediation of saline-agroecosystems.

Identification and in vitro evaluation of probiotic attributes of lactic acid bacteria isolated from fermented food sources

Consumer's vigilance towards health-promoting foods beyond only taste and nutrition has increased the recognition for probiotic products. In the present study, various parameters have been studied to define the probiotic properties of cultures isolated from different fermented products. Around 118 samples were selectively screened for antimicrobial compound (AMC) producing isolates by overlay-plate assay using Micrococcus luteus ATCC9341. Among 134 zone producing isolates, 48 cultures showing Gram-positive, catalase negative, non-spore forming and non-motile rods and cocci were selected. Subsequently, 18 strains were chosen based on non-hemolytic, absence of biogenic amine production, gelatinase and lecithinase negative trait for safer isolates. These were identified by biochemical assays and then subjected to RAPD-PCR. The selected cultures DB-1aa, DB-b2-15b, Cu2-PM7, Cu3-PM8 and IB-pM15 were identified by 16S rDNA sequencing as Enterococcus durans, Enterococcus faecium, Lactobacillus plantarum, and two Lactobacillus fermentum, respectively. Several in vitro experiments were carried out including acid and bile tolerance, survival under simulated gastrointestinal condition, adhesion assay to evaluate the probiotic potential of the isolates. In addition, the isolates were studied for competent properties such as antibacterial, antioxidant activity, and enzyme production for their functional application. The results of the study prove the efficiency of selected isolates as potential probiotic cultures and hence can be recommended for application in any functional food formulations.

Probiotics, Prebiotics, Synbiotics, and Paraprobiotics as a Therapeutic Alternative for Intestinal Mucositis

Intestinal mucositis, a cytotoxic side effect of the antineoplastic drug 5-fluorouracil (5-FU), is characterized by ulceration, inflammation, diarrhea, and intense abdominal pain, making it an important issue for clinical medicine. Given the seriousness of the problem, therapeutic alternatives have been sought as a means to ameliorate, prevent, and treat this condition. Among the alternatives available to address this side effect of treatment with 5-FU, the most promising has been the use of probiotics, prebiotics, synbiotics, and paraprobiotics. This review addresses the administration of these "biotics" as a therapeutic alternative for intestinal mucositis caused by 5-FU. It describes the effects and benefits related to their use as well as their potential for patient care.

Ultrasound-, subcritical water- and ultrasound assisted subcritical water-derived Tartary buckwheat polyphenols show superior antioxidant activity and cytotoxicity in human liver carcinoma cells

The effects of ultrasound-assisted (UAE), subcritical water (SWE) and ultrasound assisted-subcritical water (UA-SWE) treatments on tartary buckwheat polyphenol yield, composition, antioxidant activity and cytotoxicity in human liver carcinoma cells were studied. Folin Ciocalteu assay was used to measure total free phenol content (TFPC), and ABTS, DPPH, FRAP and TEAC assays were used to measure antioxidant activity (AA). Polyphenol characterization was done by LC-MS and cell antioxidant activity (CAA) and cytotoxicity were done using the 2,2'-Azobis-(2-amidinopropane) dihydrochloride [ABAP] and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide [MTT] assays respectively. The highest polyphenol yield was obtained by SWE (53.3 mg g^-1), followed by UA-SWE (31.8 mg g^-1), UAE (19.3 mg g^-1) and HWE (4.2 mg g^-1). Also, SWE had the highest TFPC (7.9 mgGAE/gdw). UAE and UA-SWE showed no differences with TFPC being 6.6 and 6.8 mgGAE/gdw, respectively. The control method (HWE) had the largest number of phenolic compounds identified (25), followed by UAE, SWE and UA-SWE which had 20, 13 and 11 phenolics respectively. Beside phenolic acids, all treatments extracted a number of flavonoids such as flavan-3-ols (catechin-7-O-glucoside, epigallocatechin-3-gallate, epigallocatechin, epicatechin), flavonols (kaempferol-3-O-glucoside, kaempferol, kaempferol-3-rutinoside, rutin, quercetin, quercetin-3-O-glucuronide hyperin), flavones (vitexin, isovitexin, orientin, isoorientin) and anthocyanins (cyanidin-3-O-rutinoside, Cyanidin 3-O-galactoside, cyanidin-3-O-glucoside). SWE gave the highest AA for all tests. However, the AA of those obtained by UAE and UA-SWE did not vary (P < 0.05), but were higher than HWE. Different extracts had best AA at different concentrations (HWE, 300; UAE, 250; SWE, 150; UA-SWE, 200 μg/mL). The IC₅₀ of AA were 270.8 ± 21.3, 198.1 ± 16.0, 97.9 ± 13.5, and 150.4 ± 12.8 μg/mL, respectively for HWE, UAE, SWE and UA-SWE. Generally, SWE and UA-SWE showed the highest cytotoxic activities, followed by UAE, with HWE being the lowest. IC₅₀ of cytotoxicity were 76.1 ± 3.3, 79.5 ± 7.0 and 92.6 ± 4.9 µg/mL for SWE, UA-SWE and UAE, respectively. SWE is a promising method for polyphenol extraction and its combination with ultrasound should be optimized for high yield and conservation of bioactivity.

Mechanisms of halotolerant plant growth promoting Alcaligenes sp. involved in salt tolerance and enhancement of the growth of rice under salinity stress

In the present study halotolerant bacteria were isolated from saline soil (EC ~ 11.9). Based on salt tolerance and plant growth promoting characteristics isolate AF7 was selected for further study. It was identified as Alcaligenes sp. on the basis of protein profiling and 16S rRNA sequence homology. Interestingly, AF7 showed diverse PGP characters at different salinity levels. While phosphate solubilization activity was expressed up to 300 mM NaCl, siderophore production was shown up to 700 mM, zinc solubilization up to 1000 mM and indole acetic acid (IAA), gibberellic acid (GA) and exopolysaccharides (EPS) production were depicted till 1400 mM. Correlative and regression analysis suggested positive relation between IAA, GA, EPS, siderophore production and zinc solubilization capability of AF7 and salinity up to 300 mM NaCl. EPS was found to be the most significant response and there was 263% increment in presence of 300 mM NaCl when compared to non-saline control. Analysis also showed that while growth promoting attributes were significant up to a threshold salinity level, further increasing the stress deviates the mechanism towards survival involving proline, antioxidant and hydroxyl scavenging activities. Combination of halotolerant AF7 and EPS showed more than twofold increase in the vegetative growth parameters of rice at ~ 170 mM NaCl (EC 9 dS/m). The study shows the mechanisms/metabolites of the plant growth promoting bacterium (PGPB) AF7 prominently involved during the salinity stress. Study also proves that novel bioformulations can be developed by integrative use of EPS and salt tolerant-PGPB which can be effective for saline soils.