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Evaluation of vinification lees as a general medium for lactobacillus strains.

Lactobacillus species present high nutritional requirements, so it is necessary to find new low-cost nutrient components for fermentation media. This work compares the utilization of vinification lees (an important residue of wineries) from red and white winemaking technology, distilled or not. An amount of 20 g of lees/L was used as the unique nutrient to obtain lactic acid from glucose using Lactobacillus strains with different properties: L. plantarum CECT-221, L. pentosus CECT-4023, L. casei CECT-5275, and L. coryniformis subsp. torquens CECT-25600. Only L. casei using distilled lees showed values (Pmax = 92.1 g/L and Y(P/S) = 1.05 g/g) similar to those obtained with the MRS broth. The UV spectra of white and red lees, distilled or not, allowed an interpretation of the different phenolic compounds present and their influence on the fermentation. Their detoxification by extraction with organic compounds and fermentation with L. pentosus was also considered. Time courses of glucose and lactic acid were modeled according to reported models to obtain more information about the process.

Culture Media↗

Relation of biogenic amines' formation with microbiological and sensory attributes in Lactobacillus-inoculated vacuum-packed rainbow trout (Oncorhynchus mykiss) fillets.

The biogenic amine (BA) content of vacuum-packed filleted rainbow trout (Oncorhynchus mykiss) inoculated or not with two different Lactobacillus strains, individually or in combination, was monitored during refrigerated storage for 20 days and related to respective bacteriological and sensory changes occurring during the same period. Eight amines, namely putrescine, cadaverine, tyramine, tryptamine, beta-phenylethylamine, histamine, spermine, and spermidine, were determined, whereas agmatine was not detected in any of the samples. In all cases, BA concentration was higher (P < or = 0.05) in the controls compared to all inoculated treatments, whereas the trend with regard to the bacterial populations (Enterobacteriaceae, pseudomonads, and H2S-producing bacteria) and the off-odor scores was similar. Inoculation with Lactobacillus sakei CECT 4808 showed the best preservative effect among inoculated treatments. Concentrations of putrescine and cadaverine, the main BAs formed, correlated well with both spoilage bacterial counts and off-odor scores and can be useful indicators of shelf life. Spermine and spermidine contents decreased during storage, while levels of the other determined BAs remained below 10 mg/kg even after sensory rejection.

Animals↗

Heterofermentative metabolism of glucose and ribose and utilisation of citrate by the smooth biotype of Lactobacillus amylovorus NCFB 2745.

Lactobacillus amylovorus NCFB 2745 exhibits a rough colony morphology, ferments glucose homofermentatively and cannot utilise ribose. After five transfers in de Man Rogosa and Sharpe media (containing glucose and citrate) Lb. amylovorus 2745 appears smooth on agar plates; smooth cultures reverted to rough by culturing in aerobic conditions. The smooth type shows patterns of fermentation that are typical of a heterofermentative lactobacillus. Thus, the smooth morphotype produces CO2 and ethanol in addition to lactate and is able to ferment ribose. The switch in metabolism to the smooth form is accompanied by an increase in phosphoketolase and a reduction in aldolase enzyme activities. Citrate also has effects on growth rates and end-metabolites.

Citrates↗

Neonatal small bowel epithelia: enhancing anti-bacterial defense with lactoferrin and Lactobacillus GG.

BACKGROUND AND AIMS: Extremely preterm human infants have increased susceptibility to small bowel infection. We hypothesized that early colonization of the immature small intestine with Lactobacillus GG (LGG), and use of a recombinant lactoferrin (rhLF) to promote growth of LGG, would enhance gut defenses against enteroinvasive Escherichia coli. METHODS: Newborn rat pups were treated with nothing, intra-gastric LGG, or rhLF + LGG on days 3 and 4 of life. Gut colonization by LGG was quantified in lavaged jejunal and ileal fluid and gut wall homogenates on day 5 of life. Separate studies used similarly treated litters of newborn rats that were infected late on day 4 of life with E. coli [10(12) CFU/kg]. Sixteen hours later, the numbers of E. coli were measured in small bowel fluid and gut wall homogenates. RESULTS: Control pups initially had lactic acid bacteria colonize the bowel, but these bacteria were not LGG. Pups treated with LGG or rhLF + LGG had significantly higher numbers of LGG in the ileum versus jejunum. Contrary to our hypothesis, rhLF did not augment LGG colonization. After E. coli-related gut infection, planktonic [lavage fluid] and epithelia-adherent growth [gut wall homogenates] of E. coli in the small bowel were most effectively reduced by pre-treatment with rhLF and LGG (P < .05). CONCLUSION: Prophylactic therapy with recombinant human lactoferrin and the probiotic, Lactobacillus GG, act to enhance defenses against invasive E. coli in the nascent small intestine. We suggest that rhLF and LGG are therapeutic agents that may reduce necrotizing enterocolitis and gut-related sepsis in preterm human infants.

Animals↗

No effect of oral treatment with an intestinal bacterial strain, Lactobacillus rhamnosus (ATCC 53103), on birch-pollen allergy: a placebo-controlled double-blind study.

BACKGROUND: Oral probiotic bacteriotherapy with Lactobacillus rhamnosus has given promising results in small children with food allergy. We studied the effects of similar therapy in teenagers and young adults, who were allergic to birch pollen and apple food and had intermittent symptoms of atopic allergy and/or mild asthma. METHODS: We conducted a double-blind, placebo-controlled study, in which respiratory and eye symptoms and use of medications in two groups were compared. Open oral challenge tests with a slice of apple were performed trice: before, during and after the birch-pollen season. There were 18 patients in each group. They used Lactobacillus rhamnosus for 5.5 months; 2.5 months before the pollen season, 1 month during the season (May), and 2 months after. RESULTS: The results were negative. The treatment did not alleviate the symptoms of the patients or reduce their use of medication during the birch-pollen season or the subsequent 2 months. The treatment did not significantly affect the symptoms caused by apple in the oral challenge tests. CONCLUSIONS: We found no indication of a beneficial treatment effect in our patients. As the number of patients was relatively small, conclusions should be drawn with caution.

Administration, Oral↗

Effects of a milk product, fermented by Lactobacillus acidophilus and with fructo-oligosaccharides added, on blood lipids in male volunteers.

OBJECTIVE: To investigate in adult male volunteers the effect of a new fermented milk product, fermented by Lactobacillus acidophilus and with fructo-oligosaccharides added, on blood lipids. DESIGN: Randomized placebo-controlled double-blind two-way cross over trial with two treatment periods of three weeks, separated by a wash-out period of one week. SETTING: the study was performed at the TNO Nutrition and Food Research Institute in Zeist, The Netherlands. SUBECTS: Thirty normal healthy men, aged 33-64y (mean serum total cholesterol level: 5.23 +/- 1.03 (s.d.)), were selected for this study. Normal health was assessed by pre study screening. All subjects were used to an average Dutch food pattern. INTERVENTIONS: During the treatment periods subjects consumed three times daily a 125 ml of either test or reference product as a part of their habitual diet. The test product was a milk, fermented by yogurt starters and Lactobacillus acidophilus, and contained 2.5% fructo-oligosaccharides, 0.5% vegetable oil and 0.5% milk fat. The reference product was a traditional yogurt (milk fermented only by yogurt strains), containing 1% milk fat. Blood samples for serum lipid analysis and blood glucose measurements were taken before the start of the experiment and at the end of both treatment periods. RESULTS: As compared to the reference product, consumption of the test product resulted in significantly lower values for serum total cholesterol (P < 0.001), LDL-cholesterol (P < 0.005), and the LDL/HDL-ratio (P < 0.05) by 4.4, 5.4 and 5.3% respectively. Levels of serum HDL-cholesterol, triglycerides and blood glucose remained essentially unchanged. The beneficial effects of the test product on serum cholesterol were largely related to an increase of this parameter during the consumption of the reference product. CONCLUSIONS: As compared to traditional yogurt, daily consumption of three times 125 ml of test product specifically lowered serum LDL-cholesterol levels in normal healthy male adult subjects with borderline elevated levels of serum total cholesterol within three weeks.

Adult↗

A double-blind placebo-controlled study of the effects of Lactobacillus acidophilus on plasma lipids.

OBJECTIVE: To select a probiotic bacteria that would reduce serum lipids in hypercholesterolaemic volunteers. DESIGN: A strain of lactobacillus was selected for its ability to metabolise cholesterol under varying conditions in vitro. Freeze-dried Lactobacillus acidophilus or placebo were then given in a double-blind randomised crossover study to volunteers with high cholesterols. SUBJECTS: A total of 80 volunteers with elevated cholesterols. INTERVENTIONS: Volunteers were randomly allocated to receive either two capsules containing freeze-dried L. acidophilus 3 x 10(10) CFU or placebo three times a day for 6 weeks. After a 6-week washout period, volunteers were crossed over to another 6 weeks of capsules. Serum lipids were measured at the beginning and end of each interventional period. RESULTS: L. acidophilus was able to reduce cholesterol and survive in an acid and bile environment. No changes in anthropomorphic measurements or in dietary records were seen between the baseline and final records or between the two sets of baseline records. There were no changes in serum lipids seen throughout the study. CONCLUSION: Despite the ability in vitro for L. acidophilus to reduce cholesterol, no effect was seen in volunteers.

Anticholesteremic Agents↗

A lyophilized and inactivated culture of Lactobacillus acidophilus increases Helicobacter pylori eradication rates.

BACKGROUND: Acid suppression plus two antibiotics is considered the reference anti-Helicobacter pylori treatment. Reported eradication rates are around 65-80%. Human Lactobacillus acidophilus shows an in vitro inhibitory effect on the attachment of H. pylori to gastric epithelial cell lines. Culture supernatant of this bacillus seems to decrease the in vitro viability of H. pylori. AIM: To evaluate whether the supplementation with an inactivated preparation of L. acidophilus could improve the efficacy of a standard anti-H. pylori therapy. METHODS: One-hundred and twenty H. pylori-positive patients were randomly assigned to a 7-day triple therapy based on rabeprazole (20 mg b.d.), clarithromycin (250 mg t.d.s.) and amoxicillin (500 mg t.d.s.) (RCA group: 60 subjects), or to the same regimen supplemented with a lyophilized and inactivated culture of Lactobacillus acidophilus (t.d.s.) (RCAL group: 60 subjects). RESULTS: In the RCA group, eradication was successful in 72% (42 out of 58 patients) from a per protocol (PP) analysis, or 70% (42 out of 60 patients) using an intention-to treat (ITT) analysis. In the RCAL group a significant increase in the eradication rate was observed: 88% (52 out of 59 patients) from PP analysis (P=0.03), 87% (52 out of 60 patients) from ITT analysis (P=0.02). CONCLUSIONS: These results seem to confirm the in vitro anti-H. pylori effect of L. acidophilus, suggesting that the inactivated L. acidophilus could be effective in increasing eradication rates of a standard anti-H. pylori therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Effect of Lactobacillus ingestion on the gastrointestinal mucosal barrier alterations induced by indometacin in humans.

BACKGROUND: Chronic nonsteroidal anti-inflammatory drug (NSAID) ingestion strongly affects the gastrointestinal mucosa as a first stage before ulceration. Some Lactobacillus strains may stabilize the mucosal barrier by increasing mucin expression, reducing bacterial overgrowth, stimulating mucosal immunity and synthetizing antioxidant substances; these events are altered in NSAID-associated gastroenteropathy. AIM: To determine whether ingestion of the probiotic Lactobacillus GG (LGG) protects the gastrointestinal mucosa against indometacin-induced alterations of permeability. SUBJECTS AND METHODS: Four gastrointestinal permeability tests were carried out in random order in 16 healthy volunteers: (i) basal; (ii) after indometacin; (iii) after 5 days of living LGG ingestion before indometacin administration; (iv) after 5 days of heat-killed LGG ingestion before indometacin administration. RESULTS: Indometacin significantly increased basal sucrose urinary excretion (29.6 mg [17.1-42.1] vs. 108.5 mg [68.2-148.7], P=0.0030) (means [95% CI]) and lactulose/mannitol urinary excretion (1.03% [0.73-1. 32] vs. 2.93% [1.96-3.90], P=0.00012). Heat-killed LGG did not modify the indometacin-induced increase of gastrointestinal permeability, while live bacteria significantly reduced the alteration of gastric (47.8 mg [31.1-64.6], P=0.012) but not intestinal permeability induced by NSAID. CONCLUSIONS: Regular ingestion of LGG protects the integrity of the gastric mucosal barrier against indometacin, but has no effect at the intestinal level.

Adolescent↗

Randomized clinical trial of specific lactobacillus and fibre supplement to early enteral nutrition in patients with acute pancreatitis.

BACKGROUND: Microbial infection of the pancreatic tissue in patients with severe acute pancreatitis increases the morbidity and mortality rates. Colonization of the lower gastrointestinal tract and oropharynx with Gram-negative, but sometimes also Gram-positive, bacteria precedes contamination of the pancreas. The aim of this study was to determine whether lactic acid bacteria such as Lactobacillus plantarum 299 could prevent colonization of the gut by potential pathogens and thus reduce the endotoxaemia associated with acute pancreatitis. METHODS: Patients with acute pancreatitis were randomized into two double-blind groups. The treatment group received a freeze-dried preparation containing live L. plantarum 299 in a dose of 109 organisms, together with a substrate of oat fibre, for 1 week by nasojejunal tube. The control group received a similar preparation but the Lactobacillus was inactivated by heat. RESULTS: A total of 45 patients completed the study. Twenty-two patients received treatment with live and 23 with heat-killed L. plantarum 299. Infected pancreatic necrosis and abscesses occurred in one of 22 patients in the treatment group, compared with seven of 23 in the control group (P = 0.023). The mean length of stay was 13.7 days in the treatment group versus 21.4 days in the control group (P not significant). CONCLUSION: Supplementary L. plantarum 299 was effective in reducing pancreatic sepsis and the number of surgical interventions.

Acute Disease↗

Characterization of natural isolate Lactobacillus acidophilus BGRA43 useful for acidophilus milk production.

Lactobacillus acidophilus BGRA43 was selected from a set of human origin isolates of Lact. acidophilus strains for the highest growth rates and antagonistic effect against both Gram-positive and Gram-negative bacteria. The strain BGRA43 also exhibited an inhibitory effect on the growth of Clostridium sporogenes. Inhibition of this strain seems to be due to lactic acid production rather than hydrogen peroxide or bacteriocin. Growth of Lact. acidophilus BGRA43 in non-fat skim milk for 6 h at 37 degrees C resulted in a lowering of the pH value to 4.53. Besides the fast acidification, this strain generated a high viscosity of skim milk. These characteristics make the strain BGRA43 attractive for acidophilus milk production. Lactobacillus acidophilus BGRA43 produces an extracellular proteinase. Whole cells efficiently degraded casein for 3 h at 37 degrees C especially alpha- and beta-casein fractions. Total DNA isolated from the strain BGRA43 did not show any hybridization with lactococcal proteinase probes indicating that this strain produces a distinctive proteinase.

Animals↗

Development and application of an in vitro methodology to determine the transit tolerance of potentially probiotic Lactobacillus and Bifidobacterium species in the upper human gastrointestinal tract.

An in vitro methodology which mimics in vivo human upper gastrointestinal transit was developed. The transit tolerance of potentially probiotic Lactobacillus and Bifidobacterium species was determined by exposing washed cell suspensions at 37 degrees C to a simulated gastric juice (pH 2.0), containing pepsin (0.3% w/v) and sodium chloride (0.5% w/v), and a simulated small intestinal juice (pH 8.0), containing pancreatin USP (1 g l-1) and sodium chloride (5 g l-1), and monitoring changes in total viable count periodically. The methodology was also employed to determine the effect of adding milk proteins (1 g l-1), hog gastric mucin (1 g l-1) and soyabean trypsinchymotrypsin inhibitor [SBTCI] (1 g l-1) on transit tolerance. The majority (14 of 15) of isolates lost > 90% viability during simulated gastric transit. Only one isolate, Lactobacillus fermentum KLD, was considered intrinsically resistant. The addition of milk proteins, singly and in combination, generally improved gastric transit tolerance. In this regard, two isolates, Lact. casei 212.3 and Bifidobacterium infantis 25962, exhibited 100% gastric transit tolerance in the presence of milk proteins. In general, the addition of hog gastric mucin did not influence simulated gastric transit tolerance of lactobacilli but tended to increase that of bifidobacteria. However, it increased that of Lact. casei 242 and Lact. salivarius 43338 but diminished that of B. bifidum 2715 and B. animalis Bo. Selected bile salts-resistant isolates were intrinsically tolerant to simulated small intestinal transit. Only Lact. casei F19 and B. adolescentis 15703T showed significant reduction in viability after 240 min. In general, the addition of milk proteins and SBTCI did not affect simulated small intestinal transit tolerance. However, they significantly improved the intrinsic resistance of Lact. casei F19 but diminished that of B. breve 15700T. It is concluded that, whereas the majority of bile salts-resistant lactobacilli and bifidobacteria may be intrinsically sensitive to gastric transit, they are intrinsically resistant to small intestinal transit. In addition, it is postulated that milk proteins and mucin may function as both buffering agents and inhibitors of digestive protease activity in vivo, thereby protecting ingested bacterial strains during upper gastrointestinal transit.

Adult↗

The normal Lactobacillus flora of healthy human rectal and oral mucosa.

The Lactobacillus flora of the rectal and oral mucosa was sampled from 42 healthy volunteers. Species identification was carried out by numerically comparing API 50CH fermentation patterns with type strains, using an SJ-similarity cut-off level of 79%. For the largest groups, identity was further confirmed by DNA-DNA hybridizations against the type strain of the species. Seventeen lactobacilli clusters were defined, of which most were found both on rectal and oral mucosa. The largest taxa were Lactobacillus plantarum, Lact. rhamnosus and Lact. paracasei ssp. paracasei, which were isolated from 52%, 26% and 17% of the individuals, respectively. Most isolates were tested for their capacity to adhere to the human colonic cell line HT-29 in the absence and presence of methyl-alpha-D-mannoside. Mannose-sensitive adherence to HT-29 cells was encountered in two-thirds of the Lact. plantarum isolates, but infrequently among isolates of other taxa. The results suggest that Lact. plantarum is a major colonizer of the human gastrointestinal mucosa, and that its capacity to adhere to mannose-containing receptors may be of some ecological importance.

Adult↗

Purification and partial amino acid sequence of plantaricin 1.25 alpha and 1.25 beta, two bacteriocins produced by Lactobacillus plantarum TMW1.25.

Two bacteriocins produced by Lactobacillus plantarum TMW1.25 have been purified by a four-step purification procedure, including ammonium sulphate precipitation and cation-exchange chromatography followed by hydrophobic-interaction chromatography on octyl sepharose. The final purification was performed by repeated reversed-phase chromatography steps which yielded two bacteriocin fractions designated plantaricin 1.25 alpha and plantaricin 1.25 beta. The molecular masses of the peptides in these fractions were 5979 and 5203 Da, respectively. Combination of the fractions did not have any synergistic effects on bacteriocin activity, indicating that they each contain a one-peptide bacteriocin. The major peptide in the alpha fraction was blocked at its N-terminus, and a partial sequence (25 residues) could only be obtained after cleavage with CNBr. This sequence did not show clear homologies with known bacteriocins. The beta peptide has been sequenced almost completely and consists, presumably, of 53 residues. This peptide displayed strong homology to the known N-terminal part of brevicin 27 produced by Lactobacillus brevis SB27. The results showed that the beta peptide contains as many as six consecutive lysine residues at the N-terminus.

Amino Acid Sequence↗

Effects of Lactobacillus amylovorus and Bifidobacterium breve on cholesterol.

To determine the validity of the hypothesis of assimilation and/or precipitation of cholesterol by Lactobacillus and Bifidobacterium species, culture were undertaken in TPY medium containing oxgall or taurocholic acid. In the case of growing cells, both strains were able to remove cholesterol in the presence of bile salts. Nevertheless, the behaviour was different according to the kind of bile salt. In the presence of taurocholic acid, the removal of cholesterol was due to both bacterial uptake and precipitation. In the presence of Oxgall, bacterial uptake and precipitation were observed for Lactobacillus but only precipitation occurred for Bifidobacterium.

Bifidobacterium↗

Effect of pH control on lactic acid fermentation of starch by Lactobacillus manihotivorans LMG 18010T.

Lactic acid fermentation of starch by Lactobacillus manihotivorans LMG 18010T, a new amylolytic L(+) lactic acid producer, was investigated and compared with starch fermentation by Lact. plantarum A6. At non-controlled pH, growth and lactic acid production from starch by Lact. manihotivorans LMG 18010T lasted 25 h. Specific growth and lactic acid production rates continuously decreased from the onset of the fermentation, unlike Lact. plantarum A6 which was able to grow and convert starch product hydrolysis into lactic acid more rapidly and efficiently at a constant rate up to pH 4.5. In spite of complete and rapid starch hydrolysis by Lact. manihotivorans LMG 18010T during the first 6 h, only 45% of starch hydrolysis products were converted to lactic acid. When pH was maintained at 6.0, lactic acid, amylase and final biomass production by Lact. manihotivorans LMG 18010T increased markedly and the fermentation time was reduced by half. Under the same conditions, an increase only in amylase production was observed with Lact. plantarum A6. When grown on glucose or starch at pH 6.0, Lact. manihotivorans LMG 18010T had an identical maximum specific growth rate (0.35 h(-1)), whereas the maximum rate of specific lactic acid production was three times higher with glucose as substrate. Lactobacillus manihotivorans LMG 18010T did not produce amylase when grown on glucose. Based on the differences in the physiology between the two species and other amylolytic lactic acid bacteria, different applications may be expected.

Biomass↗

Arabinose fermentation by Lactobacillus plantarum in sourdough with added pentosans and alphaalpha-L-arabinofuranosidase: a tool to increase the production of acetic acid.

Sixty-five strains of obligately and facultatively heterofermentative sourdough lactic acid bacteria were screened for their capacity to grow optimally in the presence of arabinose, ribose and xylose as carbon sources. Lactobacillus alimentarius 15F, Lact. brevis 10A, Lact. fermentum 1F and Lact. plantarum 20B showed higher growth rate, cell yield, acidification rate and production of acetic acid when some pentoses instead of maltose were added to the SDB medium. Lactobacillus plantarum 20B used arabinose also in a synthetic medium where complex growth factors such as yeast extract were omitted. Other Lact. plantarum strains did not show the same property. Pentosan extract was treated with alpha-L-arabinofuranosidase from Aspergillus niger or endo-xylanase from Bacillus subtilis to produce hydrolysates containing mainly arabinose and xylose, respectively. In particular, the hydrolysate containing arabinose substantiated the growth and the production of lactic acid and, especially, of acetic acid by Lact. plantarum 20B. Sourdough fermentation by Lact. plantarum 20B with addition of pentosan extract and alpha-L-arabinofuranosidase increased the acidification rate, titratable acidity and acetic acid content compared with traditional sourdough. A facultatively heterofermentative strain, Lact. plantarum 20B, also produced a sourdough with an optimal fermentation quotient.

Acetic Acid↗

Production of sakacin P by Lactobacillus sakei in a completely defined medium.

In order to investigate factors influencing the production of the bacteriocin, sakacin P, Lactobacillus sakei CCUG 42687 was grown in a completely defined medium (DML-B) with 33 components. Although the maximum sakacin P concentration obtained was higher on a complex medium due to higher cell mass, the production per cell mass was higher in DML-B. Sakacin P was produced at 4-30 degrees C, with the highest specific production at low temperatures. More sakacin P was produced at uncontrolled pH compared with cultivation at pH 6.3. Tween-80 had a positive effect on sakacin P production, while addition of sodium chloride and trace metals had negative effects. The decrease in sakacin P concentration during the late growth and stationary phases was shown to be cell-independent and promoted at high temperature and pH. Some differences in production levels of sakacin P were found among six strains of Lactobacillus sakei tested.

Bacteriocins↗