Intestinal Microbial Balance Research Articles

Bifidobacterium-Rich Fecal Donor May Be a Positive Predictor for Successful Fecal Microbiota Transplantation in Patients with Irritable Bowel Syndrome

Background/Aims: Dysbiosis is associated with various systemic disorders including irritable bowel syndrome (IBS). Fecal microbiota transplantation (FMT) might restore intestinal microbial balance. The study aimed to determine the safety and efficacy of FMT in IBS patients, as well as also positive predictors for FMT. Methods: This was a single-arm, open-label study. Eligible patients were diagnosed based on Rome III Diagnostic Criteria. Fecal materials were administered to the patient via colonoscopy. The primary end point was a change in the Bristol stool form scale at 4 weeks after FMT. Recovery to types 3-4 was considered a clinical response. The secondary end point was a change in intestinal microbiota and psychological status using the Hamilton Rating Scale. Results: Ten patients were enrolled. Six patients achieved a clinical response. The diversity of patients 4 weeks after FMT increased significantly compared with patients before FMT, and that of responding patients was significantly higher than non-responder patients. The abundance of Bifidobacterium in effective donors was significantly higher than in ineffective donors and patients. Psychological status of all patients was significantly improved after FMT. Conclusions: FMT for patients with IBS is safe, and relatively effective. Bifidobacterium-rich fecal donor may be a positive predictor for successful FMT. Key Summary: (1) Dysbiosis is associated with various gastrointestinal disorders including IBS. (2) FMT has potential to restore intestinal microbial balance. (3) We showed that FMT improved stool form and psychological status of IBS patients. (4) Bifidobacterium-rich donor efficiently induced symbiosis in IBS patients.

Synbiotic loaded chitosan-Ca-alginate microparticles reduces inflammation in the TNBS model of rat colitis

New therapeutic strategies against inflammatory bowel disease (IBD) consider the usage of probiotics, prebiotics and synbiotics as beneficial for the intestinal microbial balance. Limitations of such an approach are addressed into difference in survival, persistence, colonization and variable effects among different probiotic strains, lack in understanding of probiotic mechanisms of action, as well the complex etiology of IBD. The anti-inflammatory activity of Lactobacillus casei 01 (L. casei 01) was assessed in trinitrobenzenesulphonic (TNBS) acid model of rat colitis when the probiotic was used alone and/or in combination with oligofructose-enriched inulin (Synergy 1), and as synbiotic (L. casei 01+Synergy 1) loaded chitosan-Ca-alginate microparticles; all suspended in ayran. The results from the probiotic/synbiotic treatments (8.5–8.9log CFU g−1L. casei 01 and 1.5% Synergy 1) have shown reduction in the colonic damage and increased lactobacilli counts in feces. Lactobacilli translocation to sterile extra-intestinal organs demonstrated acceptable safety of the probiotic strain used. The best effect at reducing inflammation and lesions associated with a significant decline in myeloperoxidase (MPO) activity was observed in rats that received synbiotic microparticles. This finding suggests colon targeted delivery of the probiotics/synbiotics, as an advantageous approach in prevention and treatment of IBD.

Selection of Cholesterol-Lowering Lactic Acid Bacteria and its Effects on Rats Fed with High-Cholesterol Diet.

High cholesterol level in serum is a major factor of influence for coronary heart disease. The cholesterol-lowering ability of lactic acid bacteria (LAB) without side effects makes them more and more attractive. Seventy-nine strains of LAB isolated from fermented food were screened in vitro for their ability to assimilate cholesterol. Then, ten strains which exhibited higher ability of cholesterol assimilation were investigated with the characteristics of acidic resistance, bile salt tolerance, and cell adhesion. According to the results, the best strain LP96 was picked out, and used to evaluate its effects on the high-cholesterol diet-fed rats. The results demonstrated that the levels of serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol, and liver TC and TG were reduced significantly in the groups that received the strain LP96 solution compared with the model group, and that the serum high-density lipoprotein cholesterol levels were increased without any significant difference. Furthermore, LP96 also showed good antioxidative activity and improvement of intestinal microbial balance in the rats. Thus, LP96 may be a promising probiotics with potential cholesterol-lowering ability.

Effects of Astragalus membranaceus, Codonopsis pilosula and allicin mixture on growth performance, nutrient digestibility, faecal microbial shedding, immune response and meat quality in finishing pigs.

A 12-week trial with 120 [(Landrace×Yorkshire)×Duroc] pigs (45.65±1.93kg) was conducted to evaluate the effects of Astragalus membranaceus, Codonopsis pilosula and allicin mixture (HM) supplementation on growth performance, nutrient digestibility, faecal microbial shedding, immune response and meat quality in finishing pigs. Pigs were allocated to one of three treatments with 0, 0.025% (HM1) and 0.05% (HM2) HM supplementation in a randomized complete block design according to sex and BW. Each treatment contained 10 replications with four pigs (two barrows and two gilts) per pen. Dietary HM resulted in a higher G:F (p<0.05) than CON group during weeks 7 to 12 and the overall periods. Pigs fed HM2 diet had higher ADG than pigs fed CON diet. Pigs fed HM2 supplementation diet led to a higher (p<0.05) apparent total tract digestibility (ATTD) of dry matter (DM) and gross energy (GE) than pigs fed CON diet at week 6, while the supplementation of HM led to a higher (p<0.05) ATTD of DM and GE than pigs fed CON diet at week 12. The faecal E.coli counts were reduced, and Lactobacillus counts were increased by increasing HM supplementation (p<0.05). Pigs fed HM1 diet had higher (p<0.05) WBC concentration than those fed CON and HM2 diets at week 6. Pigs fed HM-supplemented diet had higher (p<0.05) IgG and IgA concentrations than those fed CON diet at week 12. Pigs fed HM diet noted better (p<0.05) meat colour and redness value than pigs fed CON diet. Pig fed HM2 reduced (p<0.05) the lightness value compared with CON group. In conclusion, dietary HM supplementation exerted beneficial effects on growth performance, nutrient digestibility, intestinal microbial balance (increased Lactobacillus counts and decreased E.coli counts), immune response and meat quality.

The effect of volatile oil mixtures on the performance and ilio-caecal microflora of broiler chickens

The aim of this study was to investigate the individual and combined effects of rosemary, oregano and fennel volatile oil (FVO) supplementation on the performance and ilio-caecal bacteriological flora of broiler chickens.A total of 800 male Ross-308 broiler chickens were divided equally into 8 groups; each contained 100 chickens. The study included a control treatment (NC) with no dietary additives that was supplemented with oils according to the following 7 treatments: 200 mg α-tocopherol acetate/kg (PC), 100 mg oregano volatile oil (OVO)/kg, 100 mg rosemary volatile oil (RVO)/kg, 100 mg FVO/kg and an equal mixture of oregano+rosemary+fennel VO (100, 200, 400 mg/kg, VOM-1, VOM-2 and VOM-3, respectively). The experiment lasted for 6 weeks.At the end of the experiment, dietary supplementation with α-tocopherol, oregano, rosemary and FVO and two different volatile oil mixtures (VOMs) (VOM-2; VOM-3) significantly increased the body weights (BWs) of broilers at 7, 14 and 21 d of age compared to the negative control (NC) (−) and VOM-1 groups. At 0–42 d, birds fed on VOM-3 were considerably heavier and also gained more weight than NC (−) and VOM-1 groups.The blend of VOs at 400 mg/kg significantly increased Lactobacillus spp. in faeces. The blends of oregano, rosemary and FVOs (VOM-3) at 400 mg/kg concentration and also VOM-3 group exhibited stronger antibacterial activity against coliform bacteria compared to the NC (−) group.In conclusion, the blend of oregano, rosemary and fennel VOs at higher concentrations (400 mg/kg concentration) in diets can be used to stimulate the growth and can improve the intestinal microbial balance (including a reduction of coliform bacteria and an increase in Lactobacillus spp. counts) of broiler chickens.

Microencapsulation of Bacterial Cells by Emulsion Technique for Probiotic Application.

Probiotics are dietary concepts to improve the dynamics of intestinal microbial balance favorably. Careful screening of probiotic strains for their technological suitability can also allow selection of strains with the best manufacturing and food technology characteristics. However, even the most robust probiotic bacteria are currently in the range of food applications to which they can be applied. Additionally, bacteria with exceptional functional heath properties are ruled out due to technological limitations. New process and formulation technologies will enable both expansion of the range of products in to which probiotics can be applied and the use of efficacious stains that currently cannot be manufactured or stored with existing technologies. Viability of probiotics has been both a marketing and technological concern for many industrial produces. Probiotics are difficult to work with, the bacteria often die during processing, and shelf life is unpredictable. Probiotics are extremely susceptible environmental conditions such as oxygen, processing and preservation treatments, acidity, and salt concentration, which collectively affect the overall viability of probiotics. Manufacturers have long been fortifying products with probiotics; they have faced significant processing challenges regarding the stability and survivability of probiotics during processing and preservation treatments, storage as well during their passage through GIT. Application of microencapsulation significantly improves the stability of probiotics during food processing and gastrointestinal transit.

Probiotic supplementation in children with cystic fibrosis-a systematic review.

Probiotics may benefit in cystic fibrosis (CF) as gut dysbiosis is associated with gastrointestinal symptoms and exacerbation of respiratory symptoms in CF. We conducted a systematic review of randomized controlled trials (RCTs) and non-RCTs of probiotic supplementation in children with CF, using the Cochrane methodology, preferred reporting items for systematic reviews (PRISMA) statement, and meta-analysis of observational studies in epidemiology (MOOSE) guidelines. Primary outcomes were pulmonary exacerbations, duration of hospitalization and antibiotics, and all-cause mortality. Secondary outcomes included gastrointestinal symptoms, markers of gut inflammation, and intestinal microbial balance. A total of nine studies (RCTs, 6, non-RCTs, 3; N=275) with some methodological weaknesses were included in the review. The pooled estimate showed significant reduction in the rate of pulmonary exacerbation (fixed effects model, two parallel group RCTs and one cross-over trial: relative risk (RR) 0.25, (95% confidence interval (95% CI) 0.15,0.41); p<0.00001; level of evidence: low) and decrease in fecal calprotectin (FCLP) levels (fixed effect model, three RCTs: mean difference (MD) -16.71, 95% CI -27.30,-6.13); p=0.002; level of evidence: low) after probiotic supplementation. Probiotic supplementation significantly improved gastrointestinal symptoms (one RCT, one non-RCT) and gut microbial balance (decreased Proteobacteria, increased Firmicutes, and Bacteroides in one RCT, one non-RCT). Limited low-quality evidence exists on the effects of probiotics in children with CF. Well-designed adequately powered RCTs assessing clinically meaningful outcomes are required to study this important issue. • Gut dysbiosis is frequent in children with cystic fibrosis due to frequent exposure to pathogens and antibiotics. • Probiotics decrease gut dysbiosis and improve gut maturity and function. What is New: • This comprehensive systematic review shows that current evidence on the safety and efficacy of probiotics in children with cystic fibrosis is limited and of low quality. • Well-designed and adequately powered trials assessing clinically important outcomes are required considering the health burden of cystic fibrosis and the potential benefits of probiotics.

Susceptibility of lactic acid bacteria, bifidobacteria and other bacteria of intestinal origin to chemotherapeutic agents

Chemotherapy is a cornerstone of cancer treatment but it can have serious side effects, such as intestinal mucositis. This work reports the susceptibility/resistance profiles of 34 species of lactic acid bacteria (LAB), bifidobacteria and other intestinal bacteria from different collections to various chemotherapeutic agents (CAs) currently used in cancer treatments in an attempt to identify microorganisms that could prevent or treat mucositis symptoms. The highest concentrations of the CAs tested were equal to or higher than those reached in plasma during anticancer treatments. All 34 species proved to be resistant at the highest concentrations assayed [minimum inhibitory concentrations (MICs) > 128 µg/mL] to capecitabine, cyclophosphamide, docetaxel, erlotinib, gefitinib, irinotecan and paclitaxel. For doxorubicin, 5-fluorouracil, gemcitabine and, especially, afatinib and pemetrexed, interspecies variation in the MIC was observed. In further work to assess the interspecies and intraspecies variability, MICs of the CAs pemetrexed and afatinib were determined for 32 strains belonging to four Bifidobacterium spp. of intestinal origin. For pemetrexed, a bimodal MIC curve was obtained (modes <2–8 µg/mL and >256 µg/mL), whilst a normal unimodal curve was obtained for afatinib (mode 128 µg/mL). Altogether, these results suggest that the majority of CAs should not, by themselves, perturb the microbial populations of the gut microbiota (but considering that they could be transformed in vivo into more toxic compounds). However, LAB and bifidobacteria, which are key players in the intestinal microbial balance of the healthy state, might be particularly inhibited by CAs such as gemcitabine or doxorubicin.

Probiotics for prevention and treatment of respiratory tract infections in children: A systematic review and meta-analysis of randomized controlled trials.

Respiratory tract infections (RTIs) represent one of the main health problems in children. Probiotics are viable bacteria that colonize the intestine and affect the host intestinal microbial balance. Accumulating evidence suggests that probiotic consumption may decrease the incidence of or modify RTIs. The authors systematically reviewed data from randomized controlled trials (RCTs) to investigate the effect of probiotic consumption on RTIs in children. MEDLINE/PubMed, Embase, Cochrane Library, and Web of Science were systematically searched for RCTs regarding the effect of probiotics on RTIs in children. The outcomes included number of children experienced with at least 1 RTI episode, duration of illness episodes, days of illness per subject, and school/day care absenteeism due to infection. A random-effects model was used to calculate pooled relative risks, or mean difference (MD) with the corresponding 95% confidence interval (CI). A total of 23 trials involving 6269 children were eligible for inclusion in the systematic review. None of the trials showed a high risk of bias. The quality of the evidence of outcomes was moderate. The age range of subjects was from newborn to 18 years. The results of meta-analysis showed that probiotic consumption significantly decreased the number of subjects having at least 1 RTI episode (17 RCTs, 4513 children, relative risk 0.89, 95% CI 0.82-0.96, P = 0.004). Children supplemented with probiotics had fewer numbers of days of RTIs per person compared with children who had taken a placebo (6 RCTs, 2067 children, MD -0.16, 95% CI -0.29 to 0.02, P = 0.03), and had fewer numbers of days absent from day care/school (8 RCTs, 1499 children, MD -0.94, 95% CI -1.72 to -0.15, P = 0.02). However, there was no statistically significant difference of illness episode duration between probiotic intervention group and placebo group (9 RCTs, 2817 children, MD -0.60, 95% CI -1.49 to 0.30, P = 0.19). Based on the available data and taking into account the safety profile of RCTs, probiotic consumption appears to be a feasible way to decrease the incidence of RTIs in children.

Influenza Virus Affects Intestinal Microbiota and Secondary Salmonella Infection in the Gut through Type I Interferons.

Human influenza viruses replicate almost exclusively in the respiratory tract, yet infected individuals may also develop gastrointestinal symptoms, such as vomiting and diarrhea. However, the molecular mechanisms remain incompletely defined. Using an influenza mouse model, we found that influenza pulmonary infection can significantly alter the intestinal microbiota profile through a mechanism dependent on type I interferons (IFN-Is). Notably, influenza-induced IFN-Is produced in the lungs promote the depletion of obligate anaerobic bacteria and the enrichment of Proteobacteria in the gut, leading to a “dysbiotic” microenvironment. Additionally, we provide evidence that IFN-Is induced in the lungs during influenza pulmonary infection inhibit the antimicrobial and inflammatory responses in the gut during Salmonella-induced colitis, further enhancing Salmonella intestinal colonization and systemic dissemination. Thus, our studies demonstrate a systemic role for IFN-Is in regulating the host immune response in the gut during Salmonella-induced colitis and in altering the intestinal microbial balance after influenza infection.

Effects of Cocoa Husk Feeding on the Composition of Swine Intestinal Microbiota.

A two-diet/two-period change over experiment was performed to investigate the effects of cocoa husks, as a source of dietary fiber and polyphenols, on pig intestinal microbial composition. Six pigs were fed a conventional cereal-based diet or a diet obtained by substitution of 7.5% of the conventional diet with cocoa husks for 3 weeks. Experimental diets were isoproteic and isoenergetic. At the end of each 3 week testing period, samples of fresh feces were collected and analyzed for microbial composition by fluorescence in situ hybridization. Cocoa husks did not affect feed intake, weight gain, and feed efficiency. Analysis of fecal microbial populations, grouped by phyla, showed a decrease of Firmicutes and an increase of Bacteroidetes in cocoa husk-fed pigs. Particularly, cocoa husks reduced fecal populations of the Lactobacillus-Enterococcus group and Clostridium histolyticum and increased the Bacteroides-Prevotella group and Faecalibacterium prausnitzii, suggesting a potential for cocoa husks in the improvement of intestinal microbial balance.

Analysis of the effect of dietary protected organic acid blend on lactating sows and their piglets

The objective of the present study was to evaluate the effects of blends of dietary protected organic acid supplementation on growth performance, nutrient digestibility, blood profiles, faecal microflora, and gas emission on sows and piglets with emphasis on their modes of action to improve pig performance. A total of 12 sows with an average initial body weight (BW) of 252.40±11.7 kg were used in this trial. Growth performance, blood profiles, and nutrient digestibility of sows and piglets fed protected organic acid were evaluated. The dietary treatments included a basal diet (CON); CON + 0.1% protected organic acid; and CON + 0.2% protected organic acid. The BW and back fat of sows was checked four days prior to farrowing and at the weaning day to calculate BW loss and back fat loss during that period. Inclusion of 0.2% protected organic acid provided a greater digestibility than CON diets throughout the experimental period in lactating sows. Dietary supplementation with 0.2% protected organic acid led to a higher white blood cell and lymphocyte concentration than CON treatment in sucking piglets. Immunoglobulin G concentration observed was greater in protected organic acid groups in lactating sow and sucking piglets. Increased faecal Lactobacillus counts with decreased E. coli concentrations were observed with the diets of protected organic acid fed to lactating sows. The E. coli counts were decreased in weaning piglets. The faecal H2S contents were decreased in 0.2% protected organic acid diets during farrowing on day 1. Dietary supplementation with protected organic acid blends beneficially affects the nutrient digestibility, ileal noxious gas (NH3 and H2S) emission, as well as intestinal microbial balance in lactating sows.

Beneficial Properties of Probiotics.

Probiotics are live microorganisms that can be found in fermented foods and cultured milk, and are widely used for the preparation of infant food. They are well-known as "health friendly bacteria", which exhibit various health beneficial properties such as prevention of bowel diseases, improving the immune system, for lactose intolerance and intestinal microbial balance, exhibiting antihypercholesterolemic and antihypertensive effects, alleviation of postmenopausal disorders, and reducing traveller's diarrhoea. Recent studies have also been focused on their uses in treating skin and oral diseases. In addition to that, modulation of the gut-brain by probiotics has been suggested as a novel therapeutic solution for anxiety and depression. Thus, this review discusses on the current probiotics-based products in Malaysia, criteria for selection of probiotics, and evidences obtained from past studies on how probiotics have been used in preventing intestinal disorders via improving the immune system, acting as an antihypercholesterolemic factor, improving oral and dermal health, and performing as anti-anxiety and anti-depressive agents.

Diversification of Probiotics through Encapsulation Technology

Probiotics are live bacteria and dietary concepts to improve the intestinal microbial balance. Microencapsulation technique significantly improves the stability of probiotics during food processing and gastrointestinal transit. However, the matrix has a positive impact on survival without affecting the release of entrapped cells in simulated colonic pH solution. Maximum survival of cells has been noticed in encapsulated bacteria compared to the normal cells during different processing treatments as well as acid and bile tolerance and resistance to the gastric juices.

Effects of prebiotics and probiotics on the performance and bacterial colonization of broiler chickens

A study was undertaken to evaluate the effects of Neoxyval (antimicrobial growth promoter (AGP)), TechnoMos (prebiotic), GalliPro (probiotic) and a mixture of TechnoMos and GalliPro (symbiotic) on growth performance, carcass yield, histomorphology and intestinal bacterial counts in broilers (0 d to 42 d). Two hundred day-old Ross (308) broilers were allocated to five experimental treatments: T1 = control (CONT), T2 = T1 + Neoxyval, T3 = T1 + Gallipro, T4 = T1+ TechnoMos and T5 = T1+ Gallipro+ TechnoMos. The results revealed that birds that received T2, T4 and T3 gained more weight and converted feed more efficiently than those in T1 and T5. Longer ileal villi (492.9 µm) were recorded in birds that received T4 compared with T1 (424.7 µm) and T2 (439.9 µm). Conversely, jejunal villi length and width were not influenced by treatment. T3 eliminated Clostridium perfringens from the ileum, but not from the caecum. Generally, birds that received T3 and T5 performed similar to the AGP group, T2. The results from this study indicated that the probiotic (T3) and prebiotic (T4) used in this trial could serve as alternatives to AGP (T2). Enhancement in the performance of broilers could be explained partially by improvement in intestinal morphology and microbial balance associated with modulation of intestinal microflora and inhibition of pathogens.

Growth characteristics of Lactobacillus brevis KB290 in the presence of bile

Live Lactobacillus brevis KB290 have several probiotic activities, including immune stimulation and modulation of intestinal microbial balance. We investigated the adaptation of L. brevis KB290 to bile as a mechanism of intestinal survival. Strain KB290 was grown for 5 days at 37 °C in tryptone–yeast extract–glucose (TYG) broth supplemented with 0.5% sodium acetate (TYGA) containing 0.15%, 0.3%, or 0.5% bile. Growth was determined by absorbance at 620 nm or by dry weight. Growth was enhanced as the broth's bile concentration increased. Bile-enhanced growth was not observed in TYG broth or with xylose or fructose as the carbon source, although strain KB290 could assimilate these sugars. Compared with cells grown without bile, cells grown with bile had twice the cell yield (dry weight) and higher hydrophobicity, which may improve epithelial adhesion. Metabolite analysis revealed that bile induced more lactate production by glycolysis, thus enhancing growth efficiency. Scanning electron microscopy revealed that cells cultured without bile for 5 days in TYGA broth had a shortened rod shape and showed lysis and aggregation, unlike cells cultured for 1 day; cells grown with bile for 5 days had an intact rod shape and rarely appeared damaged. Cellular material leakage through autolysis was lower in the presence of bile than in its absence. Thus lysis of strain KB290 cells cultured for extended periods was suppressed in the presence of bile. This study provides new role of bile and sodium acetate for retaining an intact cell shape and enhancing cell yield, which are beneficial for intestinal survival.

New issues and science in broiler chicken intestinal health: intestinal microbial composition, shifts, and impacts

Intestinal health is important for maximising the health, welfare, and performance of poultry. In addition, intestinal health issues in poultry can have devastating financial impacts for producers, and food safety concerns for consumers. Until recently, intestinal health issues were seen as a handful of known infectious agents leading to a set of severe and identifiable named diseases. There is however an emerging area which depicts intestinal health as a more complex and multifaceted system than previously known. Recent progress in technology suitable for microbial community analysis has evolved our understanding of the chicken intestinal microbiome. It is now understood that shifts in the composition of microbial communities can occur. These shifts can result in a series of implications, including: disease, welfare, environmental, and food safety concerns. Minor shifts in intestinal microbial balance can result in a wide continuum of disease presentations ranging from severe to mild clinical, subclinical or asymptotic. Differential diagnosis of poultry intestinal health issues may be challenging and is important for applying appropriate treatment options. This review discusses new and emerging topics in broiler chicken intestinal health, with a focus on microbial composition, newly discovered microbial shifts in classical poultry diseases, range in severity of enteric diseases, newly identified organisms in normal intestinal flora, implications of shifts in intestinal microbial communities and diagnosis of emerging intestinal health issues in poultry.

Antenatal prevention of atopic dermatitis associated with food allergies

To establish effect of probiotic Lactobacillus reuteri which is used in women in the last pregnancy trimester, prevalence of atopic dermatitis in children of the first 6 months of life. One group of women took Lactobacillus reuteri as chewing tablets of probiotic Lactobacillus reuteri, with dairy-limited diet excluding walnuts prior delivery. The second group of pregnant women took only proposed diet. Cumulative prevalence of atopic dermatitis was lower in group of children which mothers took Lactobacillus reuteri (6.7%) during pregnancy than in group of children of mothers from control group (24.2%). Analysis of the clinical features of disease showed that in children of the main group was observed mild atopic dermatitis (SCORAD amounted to 12,3+0.14 points). In children of the control group was middle and severe of atopic dermatitis (SCORAD 22-52 points, respectively). The use of Lactobacillus reuteri by women in the last pregnancy trimester was positive for general condition and status of gastrointestinal tract. Pregnant women which took Lactobacillus reuteri had increased metabolic activity of lactic flora and recovered balance between aerobic/anaerobic microorganisms. Disorders of intestinal microbial balance in pregnant women in control group were not recovered to the end of pregnancy.

Cytotoxic effects of various lactic acid bacteria on Caco-2 cells

Probiotics are live microbial food supplements that can be considered a functional food. They benefit the health of a host animal by maintaining their intestinal microbial balance. Most probiotic microorganisms are lactic acid bacteria (LAB) such as Lactobacillus spp., Bifidobacterium spp., and Enterococcus spp. LAB have been reported to possess certain anticancer properties. The vast majority of studies on their anticancer effects have dealt with colorectal cancers, although there have also been some studies on breast and bladder cancers. Colon cancer is the fourth most common cause of cancer-related mortality in the world. The aim of this study was to investigate the antiproliferative effects of the cell-free filtrate and the cell-free lyophilized filtrate of 3 LAB (Pediococcus pentosaceus, Lactobacillus plantarum, and Weissella confusa) on human colorectal adenocarcinoma cell line Caco-2. The filtrates were found to inhibit the growth of colon cancer cells in a dose-dependent manner as detected by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, suggesting that these strains might have use as probiotics in functional food or for colon cancer treatment. There are no other studies related to the anticancer activities of W. confusa in the literature.

Characterisation and preliminary lipid-lowering evaluation of Lactobacillus isolated from a traditional Serbian dairy product.

We investigated the potential probiotic properties of indigenous lactic acid bacteria (LAB) isolated from Serbian homemade cheese. Seventeen LAB strains were isolated and characterised using standard protocols. One of the strains showed several probiotic properties: survival at low pH and in bile salts solution, antimicrobial activity, susceptibility to antibiotics and adhesion to hexodecane. DNA analysis identified the isolate as Lactobacillus casei, hereafter named L. casei 5s. The lipid lowering effect of L. casei 5s was evaluated in vivo using a hyperlipidemic rat model. Orally administered L. casei 5s significantly decreased the elevated total serum cholesterol and triglycerides, and attenuated macro vesicular steatosis in the liver. Moreover, L. casei 5s improved the intestinal microbial balance in favour of lactobacilli, while decreasing the number of Escherichia coli cells. The bacteria were re-isolated and identified from the surface of the intestinal mucosa and from the faecal samples of treated animals, indicating adhesiveness and colonisation ability. The results of an acute oral toxicity study in mice and the absence of translocation to other organs demonstrated the safety of the strain. In conclusion, L. casei 5s demonstrated promising probiotic potential and might be a good candidate for more detailed investigations.