Probiotic bacteria: safety, functional and technological properties

Use of a Potential Probiotic, Lactobacillus plantarum L7, for the Preparation of a Rice-Based Fermented Beverage

This study aimed to isolate potential probiotic lactic acid bacteria from a traditional rice-based fermented beverage "bhaati jaanr" and to evaluate their role during preparation of the beverage. Among various isolates, Lactobacillus plantarum strain L7 exhibited satisfactory in vitro probiotic characteristics such as acid resistance and bile tolerance, cell surface hydrophobicity, auto-aggregation, antibiotic susceptibility, and antimicrobial activities. Therefore, performance of L7 as a starter culture in rice fermentation was determined during a 6-day rice fermentation study. L. plantarum L7 decreased the pH, associated with an increase in total titratable acidity and organic acid production up to the 4th day of fermentation. The highest concentrations of succinic acid (0.37 mg/g), lactic acid (4.95 mg/g), and acetic acid (0.36 mg/g) were recorded on the 3rd, 4th, and 5th days of fermentation, respectively. Saccharifying (148.13 μg/min g-1) and liquefying (89.47 μg/min g-1) activities were the highest on days 3 and 2, respectively, and thereafter, they decreased. Phytase activity and the cleavage of free minerals (sodium, calcium, magnesium, manganese, and ferrous) increased up to days 3-4. The concentration of various accumulated malto-oligosaccharides (glucose, fructose, maltotriose, and maltoterose) was noted to be the maximum on days 4 and 5. Furthermore, gas chromatography-mass spectrometry analysis indicated the presence of various volatile compounds. The fermented material also exhibited 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity. Therefore, the probiotic, L. plantarum L7, has a significant role in the fermentation of this beverage and enhances its functional properties.

Selection and characterization of probiotic lactic acid bacteria and its impact on growth, nutrient digestibility, health and antioxidant status in weaned piglets

The present study was aimed to develop an effective probiotic lactic acid bacteria (LAB) from piglet feces and in vitro characterization of probiotic properties. To confirm host-species specificity of probiotics, the efficacy of isolated LAB on growth, nutrient utilization, health and antioxidant status was observed in early weaned piglets. A total of 30 LAB were isolated from feces of five healthy piglets (28d old). All isolates were Gram positive, cocco-bacilli and catalase negative. Out of thirty LAB isolates, twenty were shortlisted on the basis of their tolerance to pH (3.0, 4.0, 7.0 and 8.0) and bile salts (0.075, 0.15, 0.3 and 1.0%). Whereas, fourteen isolates were selected for further in vitro probiotic characterization due higher (P<0.05) cell surface hydrophobicity to toluene (>45 percent). These isolates fermented twenty-seven different carbohydrates but were negative for ONPG, citrate and malonate. Also enabled to synthesize amylase, protease, lipase and phytase. They were sensitive to penicillin, azithromycin, lincomycin, clindamycin, erythromycin, cephalothin and chloramphenicol and resistant to ciprofloxacin, ofloxacin, gatifloxacin, vancomycin and co-trimoxazole. Except three isolates, all showed antagonistic activity (>60% co-culture activity) against Escherichia coli, Salmonella Enteritidis, Salmonella serotype (ser.) Typhimurium, Staphylococcus intermedius, Staph. chromogenes, Proteus mirabillis, Areomonas veonii, Bordetella bronchioseptica and Klebsialla oxytoca. The isolate Lacp28 exhibited highest tolerance to acidic pH and bile salts (up to 0.3%), phytase activity, cell surface hydrophobicity, antagonistic activity and co-culture assay (>80% growth inhibition). Host specificity of Lacp28 was further confirmed by heavy in vitro adhesion to pig intestinal epithelium cells compared to chicken. Hence, Lacp28 was selected and identified by phylogenetic analysis of 16S rRNA as Pediococcus acidilactici strain FT28 with 100% similarity (GenBank accession nos. KU837245, KU837246 and KU837247). The Pediococcus acidilactici FT28 was selected as potential probiotic candidature for in vivo efficacy in weaned pigs. Thirty-six crossbred piglets (28d) were randomly distributed into three groups (four replicates of three each) namely, basal diet without probiotics (T0) or with Lactobacillus acidophilus NCDC15 (conventional dairy-specific probiotic; T1) or Pediococcus acidilactici FT28 (swine-specific probiotic; T2). At end of the experiment, six piglets of similar body weight were selected to conduct digestion trial for estimation of nutrient digestibility. Results of the study indicated that supplementation of both probiotics improved (P<0.001) FCR compared to control without significant effect in average daily gain and DM intake. However, the apparent digestibility of crude protein and ether extract was better (P<0.01) in pigs fed P. acidilactici FT28 compared control and L. acidophilus fed groups. The total WBC and RBC count, serum glucose, total protein, albumin and globulin concentration was higher (P<0.05) in P. acidilactici FT28 fed group with better (P<0.05) catalase and superoxide dismutase activity measured in erythrocyte. It is concluded that species-specific Pediococcus acidilactici FT28 isolated with potential in vitro probiotic properties and also hold probiotic candidature by showing the potential capabilities with higher nutrient digestibility, heamato-biochemical and antioxidant status compared to control and Lactobacillus acidophilus NCDC15.

Growth Capacity of a Novel Potential Probiotic Lactobacillus paracasei K5 Strain Incorporated in Industrial White Brined Cheese as an Adjunct Culture

In this study, a novel potential probiotic strain Lactobacillus paracasei K5, previously isolated from traditional Greek Feta cheese and kefir grains, was evaluated as an adjunct culture for industrial white brined cheese production. Targeting industrial applications, apart from free cell cultures, a novel ready-to-use freeze-dried immobilized biocatalyst was prepared. The biocatalyst composed of L. paracasei K5 cells immobilized on delignified wheat bran prebiotic carrier and was freeze-dried without cryoprotectants. The adjunct free or immobilized culture was added separately without prior adaptation during white brined cheese manufacture and the produced cheeses were compared with commercial white brined cheeses. Several parameters that affect the acceptability and quality of the cheeses, including microbial populations, physicochemical parameters, volatile by-products and organoleptic characteristics, were analyzed through 70 days of storage. Results showed that the viability of the adjunct culture added either free or immobilized remained in high levels (7 to 8 log cfu/g) during maturation and storage. In addition, all white brined cheeses with the adjunct probiotic culture showed a sharp decrease in spoilage and pathogenic microorganisms such as enterobacteria, salmonella, staphylococci and coliforms during cheese maturation, especially when compared with the commercial white brined cheeses. Finally, after maturation time exceeded, all cheeses were characterized as safe for human consumption. Cheeses volatile compounds were significantly enhanced by the incorporated immobilized biocatalysts. These findings indicate the potential industrial use of freeze-dried ready-to-use immobilized lactobacilli as reinforcement adjunct cultures for the production of good-quality functional cheese products.

PRACTICAL APPLICATION

The launch on market of novel foods developed by the incorporation of functional ingredients provides potential benefits to consumers' diet and new business opportunities for producers. Probiotic food products are one significant category of functional foods. Thus, this study focused on the development of a novel ready-to-use freeze-dried potential probiotic biocatalyst for functional white brined cheese production. The potential industrial application of such biocatalysts is highlighted by their incorporation as adjunct cultures that resulted in good-quality functional cheeses.

Antibiotic resistance, biochemical typing, and PFGE typing of Bifidobacterium strains commonly used in probiotic health foods

This study firstly analyzed the antibiotic resistance, biochemical typing, and pulsed-field gel electrophoresis typing of 45 Bifidobacterium strains commonly used in health foods. Most strains were resistant to antibiotics but their antibiotic resistance rates were not high: Fos (56.52%), TET (43.48%), CRO (21.74%), AMC (15.22%), GEN (13.04%), RIF (10.87%), CHL (8.7%), CTX (6.52%), VAN (4.35%), and ERY (4.35%). The 45 strains could be divided into 14 pulsed-field gel electrophoresis types, of which the strain numbers of six pulsed-field gel electrophoresis types were more than one. All the Bifidobacterium strains could be divided into nine types by API50CHL biochemical identification. The same species displayed same biochemical typings, expect for B. animalis. Furthermore, the results confirmed that the same pulsed-field gel electrophoresis-type strains had closer antibiotic resistance patterns, and the same biochemical-type strain also had similar antibiotic resistance patterns.

Probiotic potential of novel Lactobacillus strains isolated from salted-fermented shrimp as antagonists for Vibrio parahaemolyticus

Lactobacillus strains have been considered good candidates as biological control agents for prevention or treatment of plant and animal infections. One L. plantarum strain FB003 and three strains (FB011, FB081, and FB110) which closed to L. sakei were isolated from fermented and salted shrimp and their abilities in inhibiting growth of Vibrio parahaemolyticus were characterized. These strains were selected as potential probiotics based on their oro-gastro-intestinal resistance, gut colonization, adhesion to Caco-2 cells, antimicrobial activities, antibiotic resistance, and safety aspects. Results of this study revealed that these isolates possessed high aggregation activities against pathogens in host intestines. Strain FB011 strain showed higher coaggregation and immunomodulatory activity in the gastro-intestinal tract than L. plantarum. These difference effects of Lactobacillus strains provide valuable information about using them to prevent Vibrio infections in the aquaculture industry.

Targeting gut microbiota in hepatocellular carcinoma: probiotics as a novel therapy

Hepatocellular carcinoma (HCC), the most common primary liver cancer, is one of the dreaded complications of chronic liver disease. Recent experimental and clinical studies have revealed that the alteration of gut-liver axis plays a pivotal role in the onset of chronic liver diseases, including HCC. Altered gut microbiota and endotoxemia are increasingly recognized as critical components in promoting the progression of chronic liver diseases to HCC. Probiotics have been suggested as a novel, safe and cost-effective approach to prevent or treat HCC. Mechanisms by which probiotics exerts their anti-cancer effects include their ability to bind carcinogens, modulation of gut microbiota, improvement of intestinal barrier function, and immunomodulation. This review summarizes the literature findings of the changes in gut microbiota linked to HCC, and discusses the possible therapeutic implications of probiotics for HCC.

Probiotic lactic acid bacteria isolated from traditional Korean fermented foods based on β-glucosidase activity

This study was designed to isolate lactic acid bacteria (LAB) with β-glucosidase activity and probiotic properties from Korean fermented foods. Among nine isolates, four LAB strains had excellent survival rates at pH 2.5 with 0.3% (w/v) pepsin for 3 h and 0.3% (w/v) oxgall for 24 h. Four LAB strains did not produce β-glucuronidase and showed adhesion ability to HT-29 cells that was superior to that shown by the reference strain Lactobacillus rhamnosus GG. All four strains were sensitive to ampicillin, tetracycline, chloramphenicol, and doxycycline. These strains were identified as Leuconostoc mesenteroides H40, Lactobacillus plantarum FI10604, L. brevis FI10700, and L. perolens FI10842 by 16S rRNA gene sequence, respectively. It was found that L. perolens FI10842 produced the highest β-glucosidase activity (49.10 mU/mL). These results indicate that the four LAB strains could be used as potential probiotic. Especially L. perolens FI10842 could be used as a starter culture for fermentation.

Potential interactions among phenolic compounds and probiotics for mutual boosting of their health-promoting properties and food functionalities - A review

Several foods are rich sources of phenolic compounds (PC) and their beneficial effects on human health may be increased through the action of probiotics. Additionally, probiotics may use PC as substrates, increasing their survival and functionality. This review presents available studies on the effects of PC on probiotics, including their physiological functionalities, interactions and capability of surviving during exposure to gastrointestinal conditions and when incorporated into food matrices. Studies have shown that PC can improve the adhesion capacity and survival of probiotics during exposure to conditions that mimic the gastrointestinal tract. There is strong evidence that PC can modulate the composition of the gut microbiota in hosts, improving a variety of biochemical markers and risk factors for chronic diseases. Available literature also indicates that metabolites of PC formed by intestinal microorganisms, including probiotics, exert a variety of benefits on host health. These metabolites are typically more active than parental dietary PC. The presence of PC commonly enhances probiotic survival in different foods. Finally, further clinical studies need to be developed to confirm in vitro and experimental findings concerning the beneficial interactions among different PC and probiotics.

Molecular typing of Lactobacillus brevis isolates from Korean food using repetitive element-polymerase chain reaction

Lactobacillus brevis is a part of a large family of lactic acid bacteria that are present in cheese, sauerkraut, sourdough, silage, cow manure, feces, and the intestinal tract of humans and rats. It finds its use in food fermentation, and so is considered a "generally regarded as safe" organism. L. brevis strains are extensively used as probiotics and hence, there is a need for identifying and characterizing these strains. For identification and discrimination of the bacterial species at the subspecific level, repetitive element-polymerase chain reaction method is a reliable genomic fingerprinting tool. The objective of the present study was to characterize 13 strains of L. brevis isolated from various fermented foods using repetitive element-polymerase chain reaction. Repetitive element-polymerase chain reaction was performed using three primer sets, REP, Enterobacterial Repetitive Intergenic Consensus (ERIC), and (GTG)₅, which produced different fingerprinting patterns that enable us to distinguish between the closely related strains. Fingerprinting patterns generated band range in between 150 and 5000 bp with REP, 200-7500 bp with ERIC, and 250-2000 bp with (GTG)₅ primers, respectively. The Jaccard's dissimilarity matrices were used to obtain dendrograms by the unweighted neighbor-joining method using genetic dissimilarities based on repetitive element-polymerase chain reaction fingerprinting data. Repetitive element-polymerase chain reaction proved to be a rapid and easy method that can produce reliable results in L. brevis species.

Complete genome sequence of Lactobacillus pentosus SLC13, isolated from mustard pickles, a potential probiotic strain with antimicrobial activity against foodborne pathogenic microorganisms

Background

Lactobacillus pentosus SLC13 is a high exopolysaccharide (EPS)-producing strain with broad-spectrum antimicrobial activity and the ability to grow in simulated gastrointestinal conditions. SLC13 was isolated from mustard pickles in Taiwan for potential probiotic applications. To better understand the molecular base for its antimicrobial activity and high EPS production, entire genome of SLC13 was determined by PacBio SMRT sequencing.

Results

L. pentosus SLC13 contains a genome with a 3,520,510-bp chromosome and a 62,498-bp plasmid. GC content of the complete genome was 46.5% and that of plasmid pSLC13 was 41.3%. Sequences were annotated at the RAST prokaryotic genome annotation server, and the results showed that the genome contained 3172 coding sequences and 82 RNA genes. Seventy-six protein-coding sequences were identified on the plasmid pSLC13. A plantaricin gene cluster, which is responsible for bacteriosins biosynthesis and could be associated with its broad-spectrum antimicrobial activity, was identified based on comparative genomic analysis. Two gene clusters involved in EPS production were also identified.

Conclusion

This genomic sequence might contribute to a future application of this strain as probiotic in productive livestock potentially inhibiting competing and pathogenic organisms.

Exploring the prebiotic effect of cyclodextrins on probiotic bacteria entrapped in carboxymetyl cellulose-chitosan particles

In this work the prebiotic effect of different cyclodextrins, CDs, on the viability of model probiotic bacteria (Lactobacillus rhamnosus GG) encapsulated in carboxymethyl cellulose-chitosan (CMC-Cht) hybrid particles was studied. All the CDs tested were observed to considerably improve the viability (quantitatively like common prebiotics, such as corn starch) and encapsulation efficiency when compared to the CD-free particles, as inferred by plate counting method and fluorescence microscopy. The SEM data suggests that the morphology of the particles, the roughness of the surface and porosity, are dependent on the type of CD and may reflect different interactions between the CDs and the matrix components. The aging and stability of the samples with and without β-CD were further evaluated. Remarkably, the viability count of the CD-doped samples was still reasonably high after one month storage at room temperature with acceptable values for practical uses. Moreover, when the CMC-Cht particles were exposed to in vitro simulated digestion fluids, the cell survival was much enhanced when the particles contained β-CD.

In vitro antifungal, probiotic, and antioxidant functional properties of a novel Lactobacillus paraplantarum isolated from fermented dates in Saudi Arabia

BACKGROUND

Fermented foods produced using dates are used in Gulf countries as beneficial and healthful foods. The beneficial microbial flora in fermented dates contributes to maintaining the nutritional properties of dates by preventing the growth of spoilage fungi. Here, we examined the antifungal, probiotic, and antioxidant properties of the novel Lactobacillus strain D-3 isolated from fermented dates.

RESULTS

Analyzing the morphological, physiological, and biochemical characteristics of this strain demonstrated that it was similar to Lactobacillus species, and molecular-level amplification of the 16S rRNA gene showed that it belonged to Lactobacillus paraplantarum. Under shake flask cultivation using date juice, the strain produced significant amounts of ethanol and lactic, succinic, and acetic acids. Purification of benzoic acid extracted from the extracellular fermentation medium was confirmed by nuclear magnetic resonance, and infrared and mass spectral data revealed minimum inhibitory concentration values of 10, 20, 10, 5, and 10 mg mL^-1 for Aspergillus fumigates, Curvularia lunata, Fusarium oxysporum, Gibberella moniliformis, and Penicillium chrysogenum, respectively. The strain showed several advantages, including the ability to survive under conditions similar to the gastrointestinal tract (low pH, bile salts, and antimicrobial susceptibility) and high levels of extracellular enzyme activities. The strain's growth patterns under various concentrations of H₂ O₂ and its scavenging properties towards hydroxyl radical (64.85%) and DPPH (84.97%) were also interesting properties.

CONCLUSION

The antifungal, probiotic, and antioxidant properties of L. paraplantarum D3 may provide health benefits to consumers. © 2017 Society of Chemical Industry.

Probiotic Bacteria Alter Pattern-Recognition Receptor Expression and Cytokine Profile in a Human Macrophage Model Challenged with Candida albicans and Lipopolysaccharide

Probiotics are live microorganisms that confer benefits to the host health. The infection rate of potentially pathogenic organisms such as Candida albicans, the most common agent associated with mucosal candidiasis, can be reduced by probiotics. However, the mechanisms by which the probiotics interfere with the immune system are largely unknown. We evaluated the effect of probiotic bacteria on C. albicans challenged human macrophages. Macrophages were pretreated with lactobacilli alone (Lactobacillus rhamnosus LR32, Lactobacillus casei L324m, or Lactobacillus acidophilus NCFM) or associated with Escherichia coli lipopolysaccharide (LPS), followed by the challenge with C. albicans or LPS in a co-culture assay. The expression of pattern-recognition receptors genes (CLE7A, TLR2, and TLR4) was determined by RT-qPCR, and dectin-1 reduced levels were confirmed by flow cytometry. The cytokine profile was determined by ELISA using the macrophage cell supernatant. Overall probiotic lactobacilli down-regulated the transcription of CLEC7A (p < 0.05), resulting in the decreased expression of dectin-1 on probiotic pretreated macrophages. The tested Lactobacillus species down-regulated TLR4, and increased TLR2 mRNA levels in macrophages challenged with C. albicans. The cytokines profile of macrophages challenged with C. albicans or LPS were altered by the probiotics, which generally led to increased levels of IL-10 and IL-1β, and reduction of IL-12 production by macrophages (p < 0.05). Our data suggest that probiotic lactobacilli impair the recognition of PAMPs by macrophages, and alter the production of pro/anti-inflammatory cytokines, thus modulating inflammation.

Antiproliferation effects and antioxidant activity of two new Lactobacillus strains

Abstract The microorganisms most commonly used as probiotics are lactic acid bacteria, especially those of the genus Lactobacillus. In the present study, two Lactobacillus strains, L. pentosus ITA23 and L. acidipiscis ITA44, previously isolated from mulberry silage, were characterized for their antiproliferative and antioxidant activities. The antiproliferative effects of the strains were investigated using the MTT assay with breast cancer (MDA-MB-231), liver cancer (HepG2) and normal liver (Chang) cell lines. The strains were tested for their antioxidant activity using the FRAP and ABTS methods. The results showed that the two Lactobacillus strains had good antiproliferative effects against both cancer cell lines tested, while their effects on the normal cells were weak. Based on the results of the antioxidant tests, the intact cells and cell-free extracts of the two Lactobacillus strains showed more than 135 and less than 50 µg trolox/ml of antioxidant activity, respectively. Lactobacillus pentosus ITA23 and L. acidipiscis ITA44 can be considered as potential probiotic candidates for humans because of their antioxidant activity and antiproliferation effects against cancer cells.

Fermentation of sarshir (kaymak) by lactic acid bacteria: antibacterial activity, antioxidant properties, lipid and protein oxidation and fatty acid profile

BACKGROUND

The antioxidant and antibacterial activities of fermented sarshir (traditional dairy food), with three probiotic Lactobacillus plantarum strains (LP3, AF1, and LU5), were investigated. The oxidative stability and the lipid profile of non-fermented and fermented sarshir were compared, in addition to radical scavenging activity, as well as peroxide, anisidine and carbonyl values (PV, AnV and CV, respectively).

RESULTS

The strong antibacterial activity of fermented sarshir against common pathogenic bacteria, including Gram-negative Escherichia coli O157: H7 ATCC 35150 and Pseudomonas aeruginosa ATCC 27853, as well as Gram-positive Bacillus cereus ATCC 10876 and Staphylococcus aureus ATCC 25923, was established. Among the strains examined, L. plantarum LP3 exhibited the highest radical scavenging activity (53.1 ± 1.8%) and lowest PV (3.0 meq kg^-1 ), AnV (1.31 ± 0.06) and CV (1.4 ± 0.08). The pH of sarshir decreased from 6.2 ± 0 to 3.5 ± 0.1 during 14 h of fermentation. Incorporated bacterial cells exhibited notable viability during 10 days of cold storage (4 °C).

CONCLUSION

The fermentation of sarshir by L. plantarum strains, especially LP3, resulted in beneficial changes in radical scavenging activity, as well as PV, AnV and carbonyl values, in addition to a broad spectrum of inhibitory activity against strains of P. aeruginosa, E. coli O157:H7, B. cereus and S. aureus. © 2017 Society of Chemical Industry.

Changes in Environmental Conditions Modify Infection Kinetics of Dairy Phages

Latent period, burst time, and burst size, kinetic parameters of phage infection characteristic of a given phage/host system, have been measured for a wide variety of lactic acid bacteria. However, most studies to date were conducted in optimal growth conditions of host bacteria and did not consider variations due to changes in external factors. In this work, we determined the effect of temperature, pH, and starvation on kinetic parameters of phages infecting Lactobacillus paracasei, Lactobacillus plantarum, and Leuconostoc mesenteroides. For kinetics assessment, one-step growth curves were carried out in MRS broth at optimal conditions (control), lower temperature, pH 6.0 and 5.0 (MRS₆ and MRS₅, respectively), or in medium lacking carbon (MRS_N) or nitrogen (MRS_C) sources. Phage infection was progressively impaired as environmental conditions were modified from optimal. At lower temperature or pH, infection was delayed, as perceived by longer latent and burst times. Burst size, however, was lower, equal or higher than for controls, but this effect was highly dependent on the particular phage-host system studied. Phage infection was strongly inhibited in MRS_C, but only mildly impaired in MRS_N. Nevertheless, growth of all the bacterial strains tested was severely compromised by starvation, without significant differences between MRS_C and MRS_N, indicating that nitrogen compounds are specifically required for a successful phage infection, beyond their influence on bacterial growth.

Gut-liver axis and sterile signals in the development of alcoholic liver disease

BACKGROUND

Innate immunity plays a critical role in the development of alcohol-induced liver inflammation. Understanding the inter-relationship of signals from within and outside of the liver that trigger liver inflammation is pivotal for development of novel therapeutic targets of alcoholic liver disease (ALD).

AIM

The aim of this paper is to review recent advances in the field of alcohol-induced liver inflammation.

METHODS

A detailed literature review was performed using the PubMed database published between January 1980 and December 2016.

RESULTS

We provide an update on the role of intestinal microbiome, metabolome and the gut-liver axis in ALD, discuss the growing body of evidence on the diversity of liver macrophages and their differential contribution to alcohol-induced liver inflammation, and highlight the crucial role of inflammasomes in integration of inflammatory signals in ALD. Studies to date have identified a multitude of new therapeutic targets, some of which are currently being tested in patients with severe alcoholic hepatitis. These treatments aim to strengthen the intestinal barrier, ameliorate liver inflammation and augment hepatocyte regeneration.

CONCLUSION

Given the complexity of inflammation in ALD, multiple pathobiological mechanisms may need to be targeted at the same time as it seems unlikely that there is a single dominant pathogenic pathway in ALD that would be easily targeted using a single target drug approach.

SHORT SUMMARY

Here, we focus on recent advances in immunopathogenesis of alcoholic liver disease (ALD), including gut-liver axis, hepatic macrophage activation, sterile inflammation and synergy between bacterial and sterile signals. We propose a multiple parallel hit model of inflammation in ALD and discuss its implications for clinical trials in alcoholic hepatitis.

Effect of Inulin on the Viability of L. plantarum during Storage and In Vitro Digestion and on Composition Parameters of Vegetable Fermented Juices

The prebiotic effect of different concentrations of inulin (0, 1 and 2%) on the growth and survival of Lactobacillus plantarum (LP) CECT 220 in blended carrot and orange juices was investigated after 24 h of fermentation, during 30 days of storage at 4 °C and through the phases of gastrointestinal digestion after different storage periods. Microbiological and chemical determinations were also carried out in all juices. The lactic fermentation increased the shelf life of the fermented juices with inulin. The hygienic-sanitary quality in fermented juices was better than the control juices. During storage, the inulin improved the viability of LP and the monosaccharide concentration remained higher with respect to the juice without inulin (40% lower). At 30 days, the fermented juices with 2% inulin after in vitro digestion presented the highest survival of L. plantarum.

Biomedical and Microbiological Applications of Bio-Based Porous Materials: A Review

Extensive employment of biomaterials in the areas of biomedical and microbiological applications is considered to be of prime importance. As expected, oil based polymer materials were gradually replaced by natural or synthetic biopolymers due to their well-known intrinsic characteristics such as biodegradability, non-toxicity and biocompatibility. Literature on this subject was found to be expanding, especially in the areas of biomedical and microbiological applications. Introduction of porosity into a biomaterial broadens the scope of applications. In addition, increased porosity can have a beneficial effect for the applications which exploit their exceptional ability of loading, retaining and releasing of fluids. Different applications require a unique set of pore characteristics in the biopolymer matrix. Various pore morphologies have different characteristics and contribute different performances to the biopolymer matrix. Fabrication methods for bio-based porous materials more related to the choice of material. By choosing the appropriate combination of fabrication technique and biomaterial employment, one can obtain tunable pore characteristic to fulfill the requirements of desired application. In our previous review, we described the literature related to biopolymers and fabrication techniques of porous materials. This paper we will focus on the biomedical and microbiological applications of bio-based porous materials.

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.

The effect of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium lactis) on the accumulation of lead in rat brains

Lead is a toxic metal present in different concentrations in a wide variety of food products. Exposure to lead, even to low levels, causes acute and chronic toxicities. Lead can cross the blood-brain barrier and accumulate in the nervous system. Probiotics are live microorganisms that, when used in adequate amounts, confer a health benefit on the host. Although a recent study demonstrated that the studied bacteria have a protective effect against acute lead toxicity, no research has been found that shows the long-term impact of these bacteria in vivo. The current study surveyed the protective effects of two species of probiotics, Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12, that are most widely used in many functional foods against oral lead exposure (4 weeks) in rat brains. The results revealed that, at the end of the second week of chronic exposure to lead and probiotic bacteria, the lowest level of lead belonged to the Lactobacillus group. At the end of the fourth week, the lowest amount of lead was related to the group receiving both types of probiotics. With the physiological benefits of probiotic consumption, the bacterial solution in this study did not show high efficacy in reducing brain lead concentrations.

Capacity of lactic acid bacteria in immunity enhancement and cancer prevention

Lactic acid bacteria are associated with the human gastrointestinal tract. They are important for maintaining the balance of microflora in the human gut. An increasing number of published research reports in recent years have denoted the importance of producing interferon-gamma and IgA for treatment of disease. These agents can enhance the specific and nonspecific immune systems that are dependent on specific bacterial strains. The mechanisms of these effects were revealed in this investigation, where the cell walls of these bacteria were modulated by the cytokine pathways, while the whole bacterial cell mediated the host cell immune system and regulated the production of tumor necrosis factors and interleukins. A supplement of highly active lactic acid bacteria strains provided significant potential to enhance host's immunity, offering prevention from many diseases including some cancers. This review summarizes the current understanding of the function of lactic acid bacteria immunity enhancement and cancer prevention.

Probiotic and functional characterization of bifidobacteria of Indian human origin

AIMS

To identify and characterize the probiotic and functional attributes of bifidobacteria isolated from human sources by in vitro methods.

METHODS AND RESULTS

Twelve isolates of bifidobacteria were obtained from different human sources viz; human milk, infant and adult faeces. The preliminary identification of isolates was done using genus-specific PCR followed by species level identification using 16S rRNA sequencing. All the isolates invariably showed potential probiotic characteristics. Finally, three most promising isolates were subjected to safety evaluation and were found to be safe. These were further evaluated for their potential functional characteristics like, antioxidative, antimutagenic and cholesterol assimilation. The isolates viz; NBIF-5 (73·55 ± 0·03%) and NBIF-7 (64·06 ± 0·03%) assimilated significantly higher cholesterol than NBIF-2. The maximum antioxidative activity was observed in NBIF-2 (56·56 ± 0·28% of radical inhibition). High percentage antimutagenicity scores of 52·41 ± 2·25% and 53·68 ± 1·98% against sodium azide (NaN3) were shown by NBIF-2 and NBIF-7 respectively.

CONCLUSIONS

Three strains (NBIF-2, NBIF-5 and NBIF-7) were found to be endowed with appreciable probiotic and functional activities.

SIGNIFICANCE AND IMPACT OF THE STUDY

With growing demands for probioitcs and bifidobacteria being prominent ones, new strains of diversified origin have the potential to be explored for commercial and functional applications and thus can be added to the existing commercially available strains of this genera.

Future therapies targeted towards eliminating Candida biofilms and associated infections

INTRODUCTION

Candida species are common human commensals and cause either superficial or invasive opportunistic infections. The biofilm form of candida as opposed to its suspended, planktonic form, is predominantly associated with these infections. Alternative or adjunctive therapies are urgently needed to manage Candida infections as the currently available short arsenal of antifungal drugs has been compromised due to their systemic toxicity, cross-reactivity with other drugs, and above all, by the emergence of drug-resistant Candida species due to irrational drug use. Areas covered: Combination anti-Candida therapies, antifungal lock therapy, denture cleansers, and mouth rinses have all been proposed as alternatives for disrupting candidal biofilms on different substrates. Other suggested approaches for the management of candidiasis include the use of natural compounds, such as probiotics, plants extracts and oils, antifungal quorum sensing molecules, anti-Candida antibodies and vaccines, cytokine therapy, transfer of primed immune cells, photodynamic therapy, and nanoparticles. Expert commentary: The sparsity of currently available antifungals and the plethora of proposed anti-candidal therapies is a distinct indication of the urgent necessity to develop efficacious therapies for candidal infections. Alternative drug delivery approaches, such as probiotics, reviewed here is likely to be a reality in clinical settings in the not too distant future.