Characterization of Lactobacillus plantarum PH04, a potential probiotic bacterium with cholesterol-lowering effects

Dietary heat-killed Lactobacillus brevis SBC8803 promotes voluntary wheel-running and affects sleep rhythms in mice

AIMS

We previously reported that heat-killed Lactobacillus brevis SBC8803 enhances appetite via changes in autonomic neurotransmission. Here we assessed whether a diet supplemented with heat-killed SBC8803 affects circadian locomotor rhythmicity and sleep architecture.

MAIN METHODS AND KEY FINDINGS

Daily total activity gradually increased in mice over 4 weeks and supplementation with heat-killed SBC8803 significantly intensified the increase, which reached saturation at 25 days. Electroencephalography revealed that SBC8803 supplementation significantly reduced the total amount of time spent in non-rapid eye movement (NREM) sleep and increased the amount of time spent being awake during the latter half of the nighttime, but tended to increase the total amount of time spent in NREM sleep during the daytime. Dietary supplementation with SBC8803 can extend the duration of activity during the nighttime and of sleep during the daytime. Daily voluntary wheel-running and sleep rhythmicity become intensified when heat-killed SBC8803 is added to the diet.

SIGNIFICANCE

Dietary heat-killed SBC8803 can modulate circadian locomotion and sleep rhythms, which might benefit individuals with circadian rhythms that have been disrupted by stress or ageing.

Probiotic properties of Pediococcus strains isolated from jeotgals, salted and fermented Korean sea-food

Three Pediococcus pentosaceus strains were isolated from jeotgals, salted and fermented Korean sea-foods, and their probiotic potentials were examined. After 2 h exposure to pH 3.0, P. pentosaceus F66 survived with the survival ratio of 32.6% followed by P. pentosaceus D56 (17.2%) and P. pentosaceus A24 (7.5%). P. pentosaceus F66 also survived better (26.6%) than P. pentosaceus A24 (13.7%) and P. pentosaceus D56 (5.8%) after 2 h exposure to 0.3% bile salts. Three strains grew slowly on MRS broth with 15% NaCl (w/v), reaching the OD600 values of 0.4-0.8 in 36 h. They adhered to Caco-2 cells (10.9-13.9 CFU/cell) with similar degree of adherence of a positive control, Lactobacillus rhamnosus GG (12.8 ± 0.5 CFU/cell). Three strains possess some desirable enzyme activities such as β-galactosidase, α-glucosidase, β-glucosidase, and N-acetyl-β-glucosidase. From these results, P. pentosaceus F66 seems qualified as a probiotic and can be utilized for fermented foods including jeotgals.

Preliminary evaluation of probiotic properties of Lactobacillus strains isolated from Sardinian dairy products

Twenty-three Lactobacillus strains of dairy origin were evaluated for some functional properties relevant to their use as probiotics. A preliminary subtractive screening based on the abilities to inhibit the growth of microbial pathogens and hydrolyze conjugated bile salts was applied, and six strains were selected for further characterization including survival under gastrointestinal environmental conditions, adhesion to gut epithelial tissue, enzymatic activity, and some safety properties. All selected strains maintained elevated cell numbers under conditions simulating passage through the human gastrointestinal tract, well comparable to the values obtained for the probiotic strain Lactobacillus rhamnosus GG, and were able to adhere to Caco-2 cells to various extents (from 3 to 20%). All strains exhibited high aminopeptidase, and absent or very low proteolytic and strong β-galactosidase activities; none was found to be haemolytic or to produce biogenic amines and all were susceptible to tetracycline, chloramphenicol, erythromycin, ampicillin, and amoxicillin/clavulanic acid. Our results indicate that the Lactobacillus strains analyzed could be considered appropriate probiotic candidates, due to resistance to GIT simulated conditions, antimicrobial activity, adhesion to Caco-2 cell-line, and absence of undesirable properties. They could be used as adjunct cultures for contributing to the quality and health related functional properties of dairy products.

Physiological Characteristics and Production of Folic Acid of Lactobacillus plantarum JA71 Isolated from Jeotgal, a Traditional Korean Fermented Seafood

Folic acid, one of the B group of vitamins, is an essential substance for maintaining the functions of the nervous system, and is also known to decrease the level of homocysteine in plasma. Homocysteine influences the lowering of the cognitive function in humans, and especially in elderly people. In order to determine the strains with a strong capacity to produce folic acid, 190 bacteria were isolated from various kinds of jeotgal and chungkuk-jang. In our test experiment, JA71 was found to contain 9.03μg/mL of folic acid after 24 h of incubation in an MRS broth. This showed that JA71 has the highest folic acid production ability compared to the other lactic acid bacteria that were isolated. JA71 was identified as Lactobacillus plantarum by the result of API carbohydrate fermentation pattern and 16s rDNA sequence. JA71 was investigated for its physiological characteristics. The optimum growth temperature of JA71 was 37℃, and the cultures took 12 h to reach pH 4.4. JA71 proved more sensitive to bacitracin when compared with fifteen different antibiotics, and showed most resistance to neomycin and vancomycin. Moreover, it was comparatively tolerant of bile juice and acid, and displayed resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus with restraint rates of 60.4%, 96.7%, and 76.2%, respectively. These results demonstrate that JA71 could be an excellent strain for application to functional products.

Applications of Lactobacillus rhamnosus spent culture supernatant in cosmetic antioxidation, whitening and moisture retention applications

This study was aimed at investigating the antioxidant, whitening, and moisture-retention properties of Lactobacillus rhamnosus spent culture supernatant (Lr-SCS) in cosmetic applications. Results reveal that Lr-SCS effectively and gradually scavenges 1,1-diphenyl-2-picrylhydrazyl as well as 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cations, and increases reducing power in a dose-dependent manner. Additionally, Lr-SCS can also suppress tyrosinase activity in vitro and effectively promote moisture retention. Heat treatment at 100 °C for 30 min does not influence the functions of Lr-SCS. We conclude that Lr-SCS can be used effectively in skin care cosmetics.

Ability of lactic acid bacteria isolated from mink to remove cholesterol: in vitro and in vivo studies

This study evaluated the cholesterol-lowering property of lactic acid bacteria (LAB) isolated from mink. Two strains, Enterococcus faecium MDF1104 and Lactobacillus plantarum MDL1118, were shown to remove cholesterol from broths of natural hen egg yolk and skimmed milk. The cholesterol in hen egg yolk was reduced by 58.15% and 38% by L. plantarum and E. faecium, respectively. When the bacteria were used in combination, 48.95% (p < 0.01) of cholesterol was removed from skimmed milk. Experimental mice remained healthy when fed different doses of the LAB, and the total serum cholesterol concentration was the lowest (0.90 mmol/L) (p < 0.01) when a combination of L. plantarum and E. faecium was used. Based on our results, we suggest that L. plantarum MDL1118, E. faecium MDF1104, or a combination of the 2 strains could be considered as promising cholesterol-lowering probiotics.

Role of Probiotics in health improvement, infection control and disease treatment and management

Research which concerns the usefulness of Probiotics show increasing interest based on the rise of their publications, products and the awareness of the public of their benefits. There is increasing interest concerning Probiotics from the public, researchers, governmental organizations (such as the WHO/FAO) and medicinal and food companies. Probiotics means "let good microbes work for you in different fields get their benefits and take a rest". Such work will include, food digestion, production of useful products to destroy the bad microbes, complement the functions of the missed digestive enzymes (due to missed or defective genes), and to maintain the digestive system's pH, and so on. Probiotics will augment the efficiency of our biological fermentors, the digestive system. Many authors have described the history and the progress of Probiotics and their different applications. In this review, we will focus mainly on three points, health improvement, infection control and disease management, which could be eliminated by the use of different types of direct uses of Probiotics or by the use of foods containing Probiotics.

Microbiota of table olive fermentations and criteria of selection for their use as starters

Fermentation is one of the oldest methods for preserving of olives applied worldwide for thousands of years. However, olive processing is a speculative area where whether olives are fermented products or pickled products produced by organic acids and salt. Although lactobacilli and yeasts play a major role in the process, literature survey indicates that lactobacilli are less relevant at least in some types of natural green olives during fermentation. There have been significant advances recently in understanding the process to produce olives, especially the role of lactic acid bacteria and yeasts including biofilm formation on olive surfaces by these organisms. The purpose of this paper is to review the latest developments regarding the microbiota of olives on the basis of olive types, their role on the fermentation process, the interaction between both group of microorganisms and the olive surface, the possibility to use starter cultures and the criteria to select appropriate cultures.

Lactobacillus acidophilus ATCC 4356 attenuates the atherosclerotic progression through modulation of oxidative stress and inflammatory process

The aim of this study was to investigate the effect of Lactobacillus (L.) acidophilus ATCC 4356 on the progression of atherosclerosis in Apoliprotein-E knockout (ApoE(-/-)) mice and the underlying mechanisms. Eight week-old ApoE(-/-) mice were treated with L. acidophilus ATCC 4356 daily for 12 weeks. The wild type (WT) mice or ApoE(-/-) mice in the vehicle group were treated with saline only. Body weights, serum lipid levels, aortic atherosclerotic lesions, and tissue oxidative and inflammatory statuses were examined among the groups. As compared to ApoE(-/-) mice in the vehicle group, ApoE(-/-) mice treated with L. acidophilus ATCC 4356 had no changes in body weights and serum lipid profiles, but showed decreased atherosclerotic lesion size in en face aorta. In comparison with WT mice, ApoE(-/-) mice in the vehicle group showed higher levels of serum malondialdehyde (MDA), oxidized low density lipoprotein (oxLDL) and tumor necrosis factor-alpha (TNF-α), but lower levels of interleukin-10 (IL-10) and superoxide dismutase (SOD) activities in serum. Administration of L. acidophilus ATCC 4356 could reverse these trends in a dose-dependent manner in ApoE(-/-) mice. Furthermore, ApoE(-/-) mice treated with L. acidophilus ATCC 4356 showed an inhibition of translocation of NF-κB p65 from cytoplasm to nucleus, suppression of degradation of aortic IκB-α, and improvements of gut microbiota distribution, as compared to ApoE(-/-) mice in the vehicle group. Our findings suggest that administration of L. acidophilus ATCC 4356 can attenuate the development of atherosclerotic lesions in ApoE(-/-) mice through reducing oxidative stress and inflammatory response.

Effects of NS Lactobacillus strains on lipid metabolism of rats fed a high-cholesterol diet

BACKGROUND

Elevated serum cholesterol level is generally considered to be a risk factor for the development of cardiovascular diseases which seriously threaten human health. The cholesterol-lowering effects of lactic acid bacteria have recently become an area of great interest and controversy for many researchers. In this study, we investigated the effects of two NS lactobacillus strains, Lactobacillus plantarum NS5 and Lactobacillus delbrueckii subsp. bulgaricus NS12, on lipid metabolism of rats fed a high cholesterol diet.

METHODS

Thirty-two SD rats were assigned to four groups and fed either a normal or a high-cholesterol diet. The NS lactobacillus treated groups received the high-cholesterol diet supplemented with Lactobacillus plantarum NS5 or Lactobacillus delbrueckii subsp. bulgaricus NS12 in drinking water. The rats were sacrificed after a 6-week feeding period. Body weights, visceral organ and fat weights, serum and liver cholesterol and lipid levels, intestinal microbiota and liver mRNA expression levels related to cholesterol metabolism were analyzed. Liver lipid deposition and adipocyte size were evaluated histologically.

RESULTS

Compared with rats fed a high cholesterol diet, serum total cholesterol, low-density lipoprotein cholesterol, apolipoprotein B and free fatty acids levels were decreased and apolipoprotein A-I level was increased in NS5 or NS12 strain treated rats, and with no significant change in high-density lipoprotein cholesterol level. Liver cholesterol and triglyceride levels were also significantly decreased in NS lactobacillus strains treated groups. Meanwhile, the NS lactobacillus strains obviously alleviated hepatic injuries, decreased liver lipid deposition and reduced adipocyte size of high cholesterol diet fed rats. NS lactobacillus strains restored the changes in intestinal microbiota compositions, such as the increase in Bacteroides and the decrease in Clostridium. NS lactobacillus strains also regulated the mRNA expression levels of liver enzymes related to cholesterol metabolism, including the down regulation of acyl-CoA:cholesterol acyltransferase (ACAT) and the upregulation of cholesterol 7α-hydroxylase (CYP7A1).

CONCLUSION

This study suggested that the two NS lactobacillus strains may affect lipid metabolism and have cholesterol-lowering effects in rats fed a high cholesterol diet.

A mixture of trans-galactooligosaccharides reduces markers of metabolic syndrome and modulates the fecal microbiota and immune function of overweight adults

Metabolic syndrome is a set of disorders that increases the risk of developing cardiovascular disease. The gut microbiota is altered toward a less beneficial composition in overweight adults and this change can be accompanied by inflammation. Prebiotics such as galactooligosaccharides can positively modify the gut microbiota and immune system; some may also reduce blood lipids. We assessed the effect of a galactooligosaccharide mixture [Bi2muno (B-GOS)] on markers of metabolic syndrome, gut microbiota, and immune function in 45 overweight adults with ≥3 risk factors associated with metabolic syndrome in a double-blind, randomized, placebo (maltodextrin)-controlled, crossover study (with a 4-wk wash-out period between interventions). Whole blood, saliva, feces, and anthropometric measurements were taken at the beginning, wk 6, and end of each 12-wk intervention period. Predominant groups of fecal bacteria were quantified and full blood count, markers of inflammation and lipid metabolism, insulin, and glucose were measured. B-GOS increased the number of fecal bifidobacteria at the expense of less desirable groups of bacteria. Increases in fecal secretory IgA and decreases in fecal calprotectin, plasma C-reactive protein, insulin, total cholesterol (TC), TG, and the TC:HDL cholesterol ratio were also observed. Administration of B-GOS to overweight adults resulted in positive effects on the composition of the gut microbiota, the immune response, and insulin, TC, and TG concentrations. B-GOS may be a useful candidate for the enhancement of gastrointestinal health, immune function, and the reduction of metabolic syndrome risk factors in overweight adults.

Diverse effects of oats on cholesterol metabolism in C57BL/6 mice correlate with expression of hepatic bile acid-producing enzymes

PURPOSE

We previously reported that two substrains of C57BL/6 mice respond differently to oats with respect to reduction in plasma cholesterol. Analysis of this difference might offer clues to mechanisms behind the cholesterol-lowering effect of oats. Here, we address the possible roles of hepatic steroid metabolism and the intestinal microbiota in this respect.

METHODS

Female C57BL/6 mice were fed an atherogenic diet with oat bran (27 %) or control fibres for 4 weeks.

RESULTS

C57BL/6 NCrl mice responded to oat bran with 19 ± 1 % (P < 0.001) lower plasma cholesterol, 40 ± 5% (P < 0.01) higher excretion of bile acids and increased expression of the bile acid-producing hepatic enzymes CYP7A1 and CYP8B1, but none of these effects were found in C57BL/6JBomTac mice. However, on control diet, C57BL/6JBomTac had tenfold higher expression of CYP7A1 and levels of hepatic cholesterol esters than C57BL/6NCrl mice. Plasma levels of fructosamine indicated improved glycemic control by oat bran in C57BL/6NCrl but not in C57BL/6JBomTac. C57BL/6JBomTac had higher intestinal microbiota diversity, but lower numbers of Enterobacteriaceae, Akkermansia and Bacteroides Fragilis than C57BL/6NCrl mice. Oat bran increased bacterial numbers in both substrains. Microbiota diversity was reduced by oats in C57BL/6JBomTac, but unaffected in C57BL/6NCrl.

CONCLUSIONS

Our data do not support a connection between altered microbiota diversity and reduced plasma cholesterol, but the bacterial composition in the intestine may influence the effects of added fibres. The cholesterol-lowering properties of oats involve increased production of bile acids via the classical pathway with up-regulation of CYP7A1 and CYP8B1. Altered cholesterol or bile acid metabolism may interfere with the potential of oats to reduce plasma cholesterol.

Effects of probiotic Lactobacillus rhamnosus GG and Propionibacterium freudenreichii ssp. shermanii JS supplementation on intestinal and systemic markers of inflammation in ApoE*3Leiden mice consuming a high-fat diet

A high-fat diet disturbs the composition and function of the gut microbiota and generates local gut-associated and also systemic responses. Intestinal mast cells, for their part, secrete mediators which play a role in the orchestration of physiological and immunological functions of the intestine. Probiotic bacteria, again, help to maintain the homeostasis of the gut microbiota by protecting the gut epithelium and regulating the local immune system. In the present study, we explored the effects of two probiotic bacteria, Lactobacillus rhamnosus GG (GG) and Propionibacterium freudenreichii spp. shermanii JS (PJS), on high fat-fed ApoE*3Leiden mice by estimating the mast cell numbers and the immunoreactivity of TNF-α and IL-10 in the intestine, as well as plasma levels of several markers of inflammation and parameters of lipid metabolism. We found that mice that received GG and PJS exhibited significantly lower numbers of intestinal mast cells compared with control mice. PJS lowered intestinal immunoreactivity of TNF-α, while GG increased intestinal IL-10. PJS was also observed to lower the plasma levels of markers of inflammation including vascular cell adhesion molecule 1, and also the amount of gonadal adipose tissue. GG lowered alanine aminotransferase, a marker of hepatocellular activation. Collectively, these data demonstrate that probiotic GG and PJS tend to down-regulate both intestinal and systemic pro-inflammatory changes induced by a high-fat diet in this humanised mouse model.

Evaluation of probiotic properties of Lactobacillus plantarum strains isolated from Chinese sauerkraut

Lactobacillus plantarum strains isolated and identified from naturally-fermented Chinese sauerkraut were examined in vitro for potential probiotic properties and in vivo for cholesterol-lowering effect in mice. Among 7 isolated L. plantarum strains, strains S2-5 and S4-1 were found to possess desirable probiotic properties including ability to survive at pH 2.0 for 60 min, tolerate pancreatin and bile salts, adhere to Caco-2 cells, produce high β-galactosidase activity and antimicrobial activity against Escherichia coli O157 and Shigella flexneri CMCC(B). In addition, strains S2-5 and S4-1 were susceptible to several antibiotics, and capable of reducing cholesterol level in MRS medium by assimilation of cholesterol at 20.39 and 22.28 μg ml(-1), respectively. The in vivo study with L. plantarum S4-1 showed that feeding with fermented milk containing this strain was able to effectively reduce serum cholesterol level in mice, demonstrating its potential as an excellent probiotic candidate for applications in functional products.

Probiotics, prebiotics, and synbiotics: gut and beyond

The human intestinal tract has been colonized by thousands of species of bacteria during the coevolution of man and microbes. Gut-borne microbes outnumber the total number of body tissue cells by a factor of ten. Recent metagenomic analysis of the human gut microbiota has revealed the presence of some 3.3 million genes, as compared to the mere 23 thousand genes present in the cells of the tissues in the entire human body. Evidence for various beneficial roles of the intestinal microbiota in human health and disease is expanding rapidly. Perturbation of the intestinal microbiota may lead to chronic diseases such as autoimmune diseases, colon cancers, gastric ulcers, cardiovascular disease, functional bowel diseases, and obesity. Restoration of the gut microbiota may be difficult to accomplish, but the use of probiotics has led to promising results in a large number of well-designed (clinical) studies. Microbiomics has spurred a dramatic increase in scientific, industrial, and public interest in probiotics and prebiotics as possible agents for gut microbiota management and control. Genomics and bioinformatics tools may allow us to establish mechanistic relationships among gut microbiota, health status, and the effects of drugs in the individual. This will hopefully provide perspectives for personalized gut microbiota management.

Selection of potential probiotic lactobacilli for cholesterol-lowering properties and their effect on cholesterol metabolism in rats fed a high-lipid diet

The objectives of this study were to screen probiotic characteristics of lactobacilli isolated from traditionally homemade koumiss products in Xinjiang and Inner Mongolia of China, and to determine and compare the effect of the Lactobacillus strains in vivo on lipid metabolism in rats fed with a high-lipid diet. Three out of 68 strains of Lactobacillus isolated from the koumiss were screened for bile-salt resistance, acid tolerance, and different hypocholesterolemic properties. The cholesterol-lowering effects of the 3 screened strains were estimated in rats fed a high-lipid diet by determination of serum lipids, liver, and fecal cholesterol, fecal total bile acids, and short-chain fatty acids. After a 4-wk feeding period, in comparison with the control group, the groups LIP-1 and MG9-2 had a significant reduction in serum total cholesterol, triglyceride and low-density lipoprotein cholesterol, and significantly increased high-density lipoprotein, the group E7301 had similar effects on serum lipids, but the change was not significant. The groups LIP-1, MG9-2 and E7301 had a significant reduction in liver cholesterol content and an increase in fecal cholesterol content compared with the control group. Total bile acid excretion was significantly higher in rats fed MG9-2 than the other groups. Rats fed diets containing lactic acid bacteria strains had significantly higher propionic acid and butyric acid concentrations in the feces compared with the control. Results indicated that the 3 screened Lactobacillus strains were able to lower cholesterol in vitro, and reduce cholesterol effectively in vivo. The mechanisms behind the hypocholesterolemic effect of 3 strains are likely to be diverse and will need further investigation.

Reduction in cholesterol absorption in Caco-2 cells through the down-regulation of Niemann-Pick C1-like 1 by the putative probiotic strains Lactobacillus rhamnosus BFE5264 and Lactobacillus plantarum NR74 from fermented foods

Hypercholesterolaemia is a major risk factor related to atherosclerosis, and it may be influenced by our diet. This study addresses the impact of Lactobacillus rhamnosus BFE5264 (isolated from Maasai fermented milk) and Lactobacillus plantarum NR74 (from Korean kimchi) on the control of cholesterol absorption through down-regulation of Niemann-Pick C1-like 1 (NPC1L1) expression. Caco-2 enterocytes were treated with the live, heat-killed (HK) bacteria, bacterial cell wall extracts and metabolites; mRNA level and protein expression were measured. Caco-2 cells showed lower NPC1L1 expression in the presence of the live test strains than the control, elucidating down-regulation of cholesterol uptake, and were compared well with the positive control, L. rhamnosus GG. This effect was also observed with HK bacteria and cell wall fractions but not with their metabolites. The potential of some Lactobacillus strains associated with traditional fermented foods to suppress cholesterol uptake and promote its efflux in enterocytes has been suggested from these data.

The obesity and fatty liver are reduced by plant-derived Pediococcus pentosaceus LP28 in high fat diet-induced obese mice

We evaluated the effect of an oral administration of a plant-derived lactic acid bacterium, Pediococcus pentosaceus LP28 (LP28), on metabolic syndrome by using high fat diet-induced obese mice. The obese mice were divided into 2 groups and fed either a high fat or regular diet for 8 weeks. Each group was further divided into 3 groups, which took LP28, another plant-derived Lactobacillus plantarum SN13T (SN13T) or no lactic acid bacteria (LAB). The lean control mice were fed a regular diet without inducing obesity prior to the experiment. LP28 reduced body weight gain and liver lipid contents (triglyceride and cholesterol), in mice fed a high fat diet for 8 weeks (40%, 54%, and 70% less than those of the control group without LAB, and P = 0.018, P<0.001, and P = 0.021, respectively), whereas SN13T and the heat treated LP28 at 121°C for 15 min were ineffective. Abdominal visceral fat in the high fat diet mice fed with LP28 was also lower than that without LAB by 44%, although it was not significant but borderline (P = 0.076). The sizes of the adipocytes and the lipid droplets in the livers were obviously decreased. A real-time PCR analyses showed that lipid metabolism-related genes, such as CD36 (P = 0.013), SCD1 encoding stearoyl-CoA desaturase 1 (not significant but borderline, P = 0.066), and PPARγ encoding peroxisome proliferator-activated receptor gamma (P = 0.039), were down-regulated by taking LP28 continuously, when compared with those of the control group. In conclusion, LP28 may be a useful LAB strain for the prevention and reduction of the metabolic syndrome.

Effect of daily consumption of probiotic yoghurt on lipid profiles in pregnant women: a randomized controlled clinical trial

BACKGROUND

Due to enhanced fat storage primarily during the mid-pregnancy period, pregnancy is associated with elevated levels of lipid profiles. To our knowledge, no reports are available indicating the effects of probiotic yoghurt consumption on serum lipid profiles in pregnant women.

OBJECTIVE

This study was designed to determine the effects of daily consumption of probiotic yoghurt on lipid profiles of Iranian pregnant women.

METHODS

This randomized single-blinded controlled clinical trial was performed among 70 pregnant women, primigravida, aged 18-30 years old who were carrying singleton pregnancy at their third trimester. Subjects were randomly assigned to consume 200 g/d of conventional (n=33) or the probiotic group (n=37) for 9 weeks. The probiotic yoghurt was a commercially available product prepared with the starter cultures of Streptococcus thermophilus and Lactobacillus bulgaricus, enriched with probiotic culture of two strains of lactobacilli (Lactobacillus acidophilus LA5) and bifidobacteria (Bifidobacterium animalis BB12) with a total of min 1 × 10(7) colony-forming units. The conventional yoghurt contained the starter cultures of S. thermophilus and L. bulgaricus. Fasting blood samples were taken at baseline and after 9-weeks intervention to measure serum lipid profiles.

RESULTS

Although consumption of probiotic yogurt for 9 weeks had been resulted in a significant reduction in serum total- (-53.7 mg/dL, p=0.001), LDL- (-35.2 mg/dL, p=0.006) and HDL-cholesterol levels (-9.8 mg/dL, p=0.002) as well as serum triglyceride concentrations (-42.8 mg/dL, p=0.029), no significant differences were found comparing probiotic and conventional yogurts in terms of their effect on serum lipid profiles. Within-Group differences in conventional yogurt group revealed a significant reduction in HDL-cholesterol levels (-8.4 mg/dL, p=0.005) and borderline significant reduction in serum total cholesterol concentrations (-21.6 mg/dL, p=0.08).

CONCLUSION

In conclusion, consumption of probiotic yogurt among pregnant women could not affect serum lipid profiles as compared to the conventional yogurt.

Effect of probiotic yogurt containing Lactobacillus acidophilus and Bifidobacterium lactis on lipid profile in individuals with type 2 diabetes mellitus

The purpose of this study was to investigate the effects of probiotic and conventional yogurt on the lipid profile in type 2 diabetic people. In a randomized double-blind controlled trial, 60 people (23 males and 37 females) with type 2 diabetes and low-density lipoprotein cholesterol (LDL-C) greater than 2.6 mmol/L were assigned to 2 groups. Participants consumed daily 300 g of probiotic yogurt containing Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 or 300 g of conventional yogurt for 6 wk. Fasting blood samples, anthropometric measurements and 3-d, 24-h dietary recalls were collected at the baseline and at the end of the trial. Probiotic yogurt consumption caused a 4.54% decrease in total cholesterol and a 7.45% decrease in LDL-C compared with the control group. No significant changes from baseline were shown in triglyceride and high-density lipoprotein cholesterol (HDL-C) in the probiotic group. The total cholesterol:HDL-C ratio and LDL-C:HDL-C ratio as atherogenic indices significantly decreased in the probiotic group compared with the control group. Probiotic yogurt improved total cholesterol and LDL-C concentrations in type 2 diabetic people and may contribute to the improvement of cardiovascular disease risk factors.

Screening of Bile Salt Hydrolase-Active Lactic Acid Bacteria for Potential Cholesterol-Lowering Probiotic Use

.Cholesterol-lowering effect of lactic acid bacteria (LAB) with bile salt hydrolase activity is well known. In this study, 150 LAB were screened for bile salt deconjugation ability and probiotic characters. Fourteen isolates with higher bile salt deconjugation ability were initially screened out using deconjugation rate above 50% as standard. These isolates were further screened for adhesion to HT-29 cells, bile tolerance and acid resistance. Four isolates, namely Lactobacillus casei F0822, Lactobacillus casei F0422, Enterococcus faecium F0511 and Enterococcus faecium IN7.12, was finally screened out. The 4 isolates may be able to reduce serum cholesterol levels in human and thus have a potential to apply in the biomedicine field.

Effects of two Lactobacillus strains on lipid metabolism and intestinal microflora in rats fed a high-cholesterol diet

Background

The hypocholesterolemic effects of lactic acid bacteria (LAB) have now become an area of great interest and controversy for many scientists. In this study, we evaluated the effects of Lactobacillus plantarum 9-41-A and Lactobacillus fermentum M1-16 on body weight, lipid metabolism and intestinal microflora of rats fed a high-cholesterol diet.

Methods

Forty rats were assigned to four groups and fed either a normal or a high-cholesterol diet. The LAB-treated groups received the high-cholesterol diet supplemented with Lactobacillus plantarum 9-41-A or Lactobacillus fermentum M1-16. The rats were sacrificed after a 6-week feeding period. Body weights, visceral organ and fat pad weights, serum and liver cholesterol and lipid levels, and fecal cholesterol and bile acid concentrations were measured. Liver lipid deposition and adipocyte size were evaluated histologically.

Results

Compared with rats fed a high-cholesterol diet but without LAB supplementation, serum total cholesterol, low-density lipoprotein cholesterol and triglycerides levels were significantly decreased in LAB-treated rats (p < 0.05), with no significant change in high-density lipoprotein cholesterol levels. Hepatic cholesterol and triglyceride levels and liver lipid deposition were significantly decreased in the LAB-treated groups (p < 0.05). Accordingly, both fecal cholesterol and bile acids levels were significantly increased after LAB administration (p < 0.05). Intestinal Lactobacillus and Bifidobacterium colonies were increased while Escherichia coli colonies were decreased in the LAB-treated groups. Fecal water content was higher in the LAB-treated groups. Compared with rats fed a high-cholesterol diet, administration of Lactobacillus plantarum 9-41-A resulted in decreases in the body weight gain, liver and fat pad weight, and adipocytes size (p < 0.05).

Conclusions

This study suggests that LAB supplementation has hypocholesterolemic effects in rats fed a high-cholesterol diet. The ability to lower serum cholesterol varies among LAB strains. Our strains might be able to improve the intestinal microbial balance and potentially improve intestinal transit time. Although the mechanism is largely unknown, L. plantarum 9-41-A may play a role in fat metabolism.

A sensitive method for qualitative screening of bile salt hydrolase-active lactobacilli based on thin-layer chromatography

A sensitive protocol based on thin-layer chromatography (TLC) was developed to screen qualitatively bile salt hydrolase (BSH)-active lactobacilli. The sodium salts of glycocholic acid and taurocholic acid were used as substrates, and bacterial BSH activity was confirmed by detecting cholic acid as a product of the bile conjugates using a TLC assay with direct visual observation. Forty-five lactobacilli isolated from human fecal samples were tested for BSH activity by the TLC assay, a conventional plate assay, and a quantitative colorimetric assay. With the TLC and quantitative colorimetric assays, the same 24 BSH-positive strains were detected. No false-positive or false-negative results were detected by the TLC assay. However, only 20 BSH-positive strains were detected with the conventional plate assay. Compared with the conventional plate assay, the TLC assay is more sensitive for the detection of BSH activity of lactobacilli and, thus, more suitable for screening of BSH-active lactobacilli of human origin.