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PubMed1981

Salivary lactobacillus counts in the prediction of caries activity.

The aim of the study was to investigate the reliability and clinical value for prediction of caries activity of determining the number of lactobacilli in saliva, the salivary secretion rate and the presence of yeasts in the saliva. For this purpose one entire age group of pupils (115 14-year-olds) attending one of the compulsory 9-year comprehensive schools in Orebro was selected for longitudinal examination. Over a period of 64 weeks three clinical recordings were made and seven salivary samples were collected. The correlations between caries activity, caries frequency (DFS), lactobacillus counts, yeasts in saliva, salivary secretion rate and gingivitis were examined. The results showed that in spite of a well-organized dental health service, including adequate preventive measures, a pronounced variation in caries activity remained and thus a means of predicting the onset of caries would be a valuable asset. Statistically significant correlations were found between caries activity on the one hand and caries frequency and lactobacillus counts on the other. The lactobacillus count was found to be a suitable measure in predicting caries activity. It was concluded that the lactobacillus count should be used for caries prediction in healthy, properly treated patients. It is important that there are no areas of microbial retention on the teeth such as open carious lesions, poorly executed restorations, dentures or orthodontic bands. In such situations, the lactobacillus count seems to reflect the frequency of ingested fermentable carbohydrates and thus, indirectly, the risk of initiating carious lesions.

Adolescent↗
PubMed1983

Growth and end product formation of two psychrotrophic Lactobacillus spp. and Brochothrix thermosphacta ATCC 11509T at different pH values and temperatures.

Lactobacillus viridescens, Lactobacillus sp. strain 173 (homofermentative), and Brochothrix thermosphacta ATCC 11509T were studied at different pH values and temperatures in aerobic and anaerobic batch cultures. The growth rates were higher in aerobic than in anaerobic cultures. L. viridescens grew faster at pH 5.8 than at pH 6.3, whereas the opposite was true for B. thermosphacta. Lactobacillus sp. strain 173 was inhibited in air or at 8 degrees C in anaerobic culture. B. thermosphacta did not grow in anaerobic culture at pH 5.3. The following variations in growth yields were found in the different environments studied: Lactobacillus sp. strain 173, 23 to 25 g (dry weight) per mol of glucose consumed; L. viridescens, 11 to 23 g/mol; B. thermosphacta, 16 to 38 g/mol. In air, L. viridescens produced D-lactic acid, ethanol, and acetic acid, whereas no acetic acid was produced anaerobically. Acetic acid and ethanol together constituted 41 to 48% of the total product yield irrespective of pH and temperature. Lactobacillus sp. strain 173 produced a racemic mixture of D- and L-lactic acid at pH 6.3, whereas the proportion of L-lactic acid was higher than that of D-lactic acid at pH 5.3. In air, product formation of B. thermosphacta varied from a domination of L-lactic acid to increasing yields of acetoin, acetic acid, 2,3-butanediol and isovaleric acid. The effect of pH and temperature on product formation was difficult to separate from the effect of O2 availability in aerobic cultures. However, it was indicated that more 2,3-butanediol and less acetoin were produced with a decreasing temperature.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1996

Analysis of Lactobacillus phages and bacteriocins in American dairy products and characterization of a phage isolated from yogurt.

Yogurt and acidophilus milk that contain Lactobacillus acidophilus could promote human health because L. acidophilus can inhibit enteric and food-borne microbial pathogens. To evaluate the stability of diary L. acidophilus cultures, we studied whether some diary lactobacilli could be inhibited by phages or bacteriocins released by other dairy lactobacilli. From 20 yogurts and two acidophilus milks purchased at local food markets, 38 Lactobacillus strains were isolated. Eight Lactobacillus type strains were used as controls. With mitomycin induction and agar spot assay, phages and bacteriocins were isolated from these strains and their activities were analyzed. Lactobacillus strains from 11 yogurts released phages, while the strains from most of the remaining products released bacteriocins. One phage, designated phi y8, was characterized. It was spontaneously released from its host strain L. acidophilus Y8, at a rate of about 10(4)/ml. This phage lysed nine other dairy Lactobacillus strains tested. It had a burst size of 100, an elongated prolate head of 39 by 130 nm, a long, flexible but noncontractile tail of 300 nm, and a 54.3-kb linear double-stranded DNA. DNA fingerprinting analysis indicated that L. acidophilus phages of nine yogurts in this study belonged to the same type as phi y8. Although they may be sensitive to bacteriocins, all lysogens resisted further phage attacks, whereas most nonlysogens were sensitive to both phages and bacteriocins. Therefore, Lacotbacillus cultures of some American yogurts and acidophilus milks may be unstable or unsafe because they can either be inhibited by phages or bacteriocins or release them to inhibit lactobacilli or other diary products.

Animals↗
PubMed2000

Multiplex PCR for the detection of Lactobacillus pontis and two related species in a sourdough fermentation.

A specific multiplex PCR assay based on the amplification of parts of the 16S rRNA molecule was designed. Primers derived from variable regions of the 16S rRNA provided a means of easily differentiating the species Lactobacillus pontis and Lactobacillus panis. They could be clearly discriminated from the phylogenetically related species Lactobacillus vaginalis, Lactobacillus oris, and Lactobacillus reuteri and from other lactobacilli commonly known to be present in sourdough. Other strains isolated together with L. pontis from an industrial sourdough fermentation could be clearly separated from these species by comparative sequence analysis and construction of a specific PCR primer. For a fast identification a DNA isolation protocol based on the ultrasonic lysis of cells from single colonies was developed. To demonstrate the potential of such techniques for tracking these organisms in a laboratory-scale fermentation, we combined the specific PCR assay with direct DNA extraction from the organisms in the sourdough without previous cultivation.

Bread↗
PubMed2005

Starch-binding domain affects catalysis in two Lactobacillus alpha-amylases.

A new starch-binding domain (SBD) was recently described in alpha-amylases from three lactobacilli (Lactobacillus amylovorus, Lactobacillus plantarum, and Lactobacillus manihotivorans). Usually, the SBD is formed by 100 amino acids, but the SBD sequences of the mentioned lactobacillus alpha-amylases consist of almost 500 amino acids that are organized in tandem repeats. The three lactobacillus amylase genes share more than 98% sequence identity. In spite of this identity, the SBD structures seem to be quite different. To investigate whether the observed differences in the SBDs have an effect on the hydrolytic capability of the enzymes, a kinetic study of L. amylovorus and L. plantarum amylases was developed, with both enzymes acting on several starch sources in granular and gelatinized forms. Results showed that the amylolytic capacities of these enzymes are quite different; the L. amylovorus alpha-amylase is, on average, 10 times more efficient than the L. plantarum enzyme in hydrolyzing all the tested polymeric starches, with only a minor difference in the adsorption capacities.

Amino Acid Sequence↗
PubMed2005

Lactobacillus oligofermentans sp. nov., associated with spoilage of modified-atmosphere-packaged poultry products.

Unidentified lactic acid bacterium (LAB) isolates which had mainly been detected in spoiled, marinated, modified atmosphere packaged (MAP) broiler meat products during two previous studies, were identified and analyzed for their phenotypic properties and the capability to produce biogenic amines. To establish the taxonomic position of these isolates, 16S rRNA gene sequence analysis, numerical analysis of ribopatterns, and DNA-DNA hybridization experiments were done. Unexpectedly for a meat-spoilage-associated LAB, the strains utilized glucose very weakly. According to the API 50 CHL test, arabinose and xylose were the only carbohydrates strongly fermented. None of the six strains tested for production of histamine, tyramine, tryptamine, phenylethylamine, putrescine, and cadaverine were able to produce these main meat-associated biogenic amines in vitro. The polyphasic taxonomy approach showed that these strains represent a new Lactobacillus species. The six isolates sequenced for the 16S rRNA encoding genes shared the highest similarity (95.0 to 96.3%) with the sequence of the Lactobacillus durianis type strain. In the phylogenetic tree, these isolates formed a distinct cluster within the Lactobacillus reuteri group, which also includes L. durianis. Numerical analyses of HindIII-EcoRI ribotypes placed all isolates together in a cluster with seven subclusters well separated from the L. reuteri group reference strains. The DNA-DNA hybridization levels between Lactobacillus sp. nov. isolates varied from 67 to 96%, and low hybridization levels (3 to 15%) were obtained with the L. durianis type strain confirming that these isolates belong to the same species different from L. durianis. The name Lactobacillus oligofermentans sp. nov. is proposed, with strain LMG 22743T (also known as DSM 15707T or AMKR18T) as the type strain.

Animals↗
PubMed2006

Similarity and differences in the Lactobacillus acidophilus group identified by polyphasic analysis and comparative genomics.

A set of lactobacilli were investigated by polyphasic analysis. Multilocus sequence analysis, DNA typing, microarray analysis, and in silico whole-genome alignments provided a remarkably consistent pattern of similarity within the Lactobacillus acidophilus complex. On microarray analysis, 17 and 5% of the genes from Lactobacillus johnsonii strain NCC533 represented variable and strain-specific genes, respectively, when tested against four independent isolates of L. johnsonii. When projected on the NCC533 genome map, about 10 large clusters of variable genes were identified, and they were enriched around the terminus of replication. A quarter of the variable genes and two-thirds of the strain-specific genes were associated with mobile DNA. Signatures for horizontal gene transfer and modular evolution were found in prophages and in DNA from the exopolysaccharide biosynthesis cluster. On microarray hybridizations, Lactobacillus gasseri strains showed a shift to significantly lower fluorescence intensities than the L. johnsonii test strains, and only genes encoding very conserved cellular functions from L. acidophilus hybridized to the L. johnsonii array. In-silico comparative genomics showed extensive protein sequence similarity and genome synteny of L. johnsonii with L. gasseri, L. acidophilus, and Lactobacillus delbrueckii; moderate synteny with Lactobacillus casei; and scattered X-type sharing of protein sequence identity with the other sequenced lactobacilli. The observation of a stepwise decrease in similarity between the members of the L. acidophilus group suggests a strong element of vertical evolution in a natural phylogenetic group. Modern whole-genome-based techniques are thus a useful adjunct to the clarification of taxonomical relationships in problematic bacterial groups.

Genetic Variation↗
PubMed1994

Isolation of a novel IS3 group insertion element and construction of an integration vector for Lactobacillus spp.

An insertion sequence (IS) element from Lactobacillus johnsonii was isolated, characterized, and exploited to construct an IS-based integration vector. L. johnsonii NCK61, a high-frequency conjugal donor of bacteriocin production (Laf+) and immunity (Lafr), was transformed to erythromycin resistance (Emr) with the shuttle vector pSA3. The NCK61 conjugative functions were used to mobilize pSA3 into a Laf- Lafs EMs recipient. DNA from the Emr transconjugants transformed into Escherichia coli MC1061 yielded a resolution plasmid with the same size as that of pSA3 with a 1.5-kb insertion. The gram-positive replication region of the resolution plasmid was removed to generate a pSA3-based suicide vector (pTRK327) bearing the 1.5-kb insert of Lactobacillus origin. Plasmid pTRK327 inserted randomly into the chromosomes of both Lactobacillus gasseri ATCC 33323 and VPI 11759. No homology was detected between plasmid and total host DNAs, suggesting a Rec-independent insertion. The DNA sequence of the 1.5-kb region revealed the characteristics of an IS element (designated IS1223): a length of 1,492 bp; flanking, 25-bp, imperfect inverted repeats; and two overlapping open reading frames (ORFs). Sequence comparisons revealed 71.1% similarity, including 35.7% identity, between the deduced ORFB protein of the E. coli IS element IS150 and the putative ORFB protein encoded by the Lactobacillus IS element. A putative frameshift site was detected between the overlapping ORFs of the Lactobacillus IS element. It is proposed that, similar to IS150, IS1223 produces an active transposase via translational frameshifting between two tandem, overlapping ORFs.

Amino Acid Sequence↗
PubMed2002

Ineffectiveness of probiotics in preventing recurrence after curative resection for Crohn's disease: a randomised controlled trial with Lactobacillus GG.

BACKGROUND AND AIMS: Experimental studies have shown that luminal bacteria may be involved in Crohn's disease. Probiotics are a possible alternative to antibiotics. The aim of this randomised placebo controlled study was to determine if Lactobacillus GG, given by mouth for one year, could prevent Crohn's recurrent lesions after surgery or to reduce their severity. METHODS: Patients operated on for Crohn's disease in whom all of the diseased gut had been removed were randomly allocated to receive 12 billion colony forming units of Lactobacillus or identical placebo for one year. Ileocolonoscopy was performed at the end of the trial or at the onset of symptoms. Endoscopic recurrence was defined as grade 2 or higher of Rutgeerts scoring system. RESULTS: Eight of 45 patients were excluded from the trial (three for non-compliance and five for protocol violations). Clinical recurrence was ascertained in three (16.6%) patients who received Lactobacillus and in two (10.5%) who received placebo. Nine of 15 patients in clinical remission on Lactobacillus (60%) had endoscopic recurrence compared with six of 17 (35.3%) on placebo (p=0.297). There were no significant differences in the severity of the lesions between the two groups. CONCLUSIONS: Lactobacillus GG seems neither to prevent endoscopic recurrence at one year nor reduce the severity of recurrent lesions.

Adult↗
PubMed1992

Construction of a new shuttle vector for Lactobacillus.

To clone the malolactic enzyme gene from Lactobacillus sp. 89, construction of a shuttle vector able to express itself in Lactobacillus sp. 89 and Escherichia coli was undertaken. The shuttle plasmid pLE16 resulted from the union of pBR328 and of the pLB10 plasmid extracted from Lactobacillus bulgaricus 10. The bacterial transformation in Lactobacillus sp. 89 was performed by electroporation, and the clones were selected on MRS medium with 30 micrograms.mL-1 chloramphenicol added. Fifty percent of the clones from Lactobacillus sp. 89 lost their resistance to chloramphenicol following 28 generations when the selection pressure was not maintained. The restriction map of pLE16 (7600 bp) was established using several restriction enzymes.

Escherichia coli↗
PubMed2002

Sequence analysis of pLBB1, a cryptic plasmid from Lactobacillus delbrueckii subsp. bulgaricus.

The first report of the complete nucleotide sequence of a cryptic plasmid from Lactobacillus delbrueckii subsp. bulgaricus (Lactobacillus bulgaricus) is presented. The plasmid pLBB1 consists of 6127 bp with a GC content of 44.8%. No ssDNA was detected by hybridization experiments, which is consistent with the notion that pLBB1 does not replicate by a rolling circle mechanism. A putative replication region of pLBB1 was cloned and found to be functional in Lactobacillus johnsonii and Lactococcus lactis. Plasmid pLBB1 showed significant DNA sequence identity with plasmid pLL1212 from Lactobacillus delbrueckii subsp. lactis (Lactobacillus lactis) CRL1212 (GenBank accession No. AF109691). Four open reading frames (ORFs) larger than 100 amino acids were identified. ORFA shared similarity with a putative primase-helicase system, and ORFB and ORFC exhibited limited identity with a mobilization protein and a transposase, respectively. Curing experiments did not allowed us to assign a function to the ORFs.

Amino Acid Sequence↗
PubMed2001

Effect of Lactobacillus GG supplementation on antibiotic-associated gastrointestinal side effects during Helicobacter pylori eradication therapy: a pilot study.

BACKGROUND: One-week triple therapy is currently regarded as the reference of anti-Helicobacter pylori treatment. However, antibiotic-associated gastrointestinal side effects are among the major pitfalls of such regimens. Probiotic supplementation may be regarded as a therapeutic tool to prevent or reduce these troublesome drug-related manifestations. AIM: To determine whether the addition of the probiotic Lactobacillus GG to an anti-H. pylori standard triple therapy could help to prevent or minimize the occurrence of gastrointestinal side effects. METHODS: One hundred and twenty healthy asymptomatic subjects screened positive for H. pylori infection and deciding to receive eradication therapy were randomized either to 1-week pantoprazole (40 mg b.i.d.), clarithromycin (500 mg b.i.d.), tinidazole (500 mg b.i.d.) or to the same regimen supplemented with Lactobacillus GG for 14 days. Patients filled in validated questionnaires during follow-up to determine the type and severity of side effects and to judge overall tolerability. RESULTS: Bloating, diarrhea and taste disturbances were the most frequent side effects during the eradication week and were significantly reduced in the Lactobacillus GG-supplemented group (RR = 0.4, CI 0.2-0.8; RR = 0.3, CI 0.1-0.8; RR = 0.3, CI 0.1-0.7, respectively). The same pattern was observed throughout the follow-up period. Overall assessment of treatment tolerability showed a significant trend in favor of the Lactobacillus GG-supplemented group (p = 0.03). CONCLUSIONS: Lactobacillus GG supplementation beneficially affects H. pylori therapy-related side effects and overall treatment tolerance.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1992

Enhancement of the circulating antibody secreting cell response in human diarrhea by a human Lactobacillus strain.

Human Lactobacillus sp strain GG (Lactobacillus GG) administered during acute rotavirus diarrhea has been shown to promote clinical recovery. To elucidate the immune mechanisms behind such a favorable outcome, the ELISPOT (solid phase enzyme-linked immunospot) assay of Ig- and specific antibody-secreting cells among circulating lymphocytes was used, giving indirect evidence of the immunologic events in the gut. After rehydration, 39 children with acute rotavirus diarrhea, mean age 16 (SD 6) mo, randomly received either a Lactobacillus GG fermented milk product (study group) or a pasteurized yogurt (placebo group). The duration of diarrhea was significantly shorter in the study group than in the placebo group [mean 1.1 (SD 0.6) versus 2.5 (SD 1.4)d, p = 0.001]. Lactobacillus GG therapy was associated with a significantly enhanced nonspecific humoral response during the acute phase of the infection, reflected in the IgG, IgA, and IgM Ig-secreting cell numbers. At convalescence, 90% of the study group versus 46% of the placebo group had developed an IgA specific antibody-secreting cell response to rotavirus (p = 0.006). The results indicate that Lactobacillus GG promotes recovery from rotavirus diarrhea via augmentation of the local immune defense. Furthermore, specific IgA response to rotavirus is endorsed, which is possibly relevant in protection against reinfections.

Animals↗
PubMed2003

Characterization of Lactobacillus sakei by the type of stereoisomers of lactic acid produced.

Lactobacillus sakei strains were characterized by the shift of the type of stereoisomers of lactic acid produced in the presence of 50 mM sodium acetate in a medium. Of 27 Lactobacillus sakei strains studied, 20 strains showed high levels of DNA-DNA similarity with L. sakei NRIC 1071(T), and were confirmed as L. sakei. The three remaining strains were identified as Lactobacillus curvatus by DNA-DNA similarity, and three other strains were included in the cluster of Lactobacillus plantarum/Lactobacillus pentosus/Lactobacillus paraplantarum and one strain in the cluster of Lactobacillus paracasei on the basis of 16S rRNA gene sequences. Of the 20 L. sakei strains, 19 strains shifted the type of stereoisomers of lactic acid produced from the DL-type to the L-type in the presence of 50 mM sodium acetate. L. curvatus strains and strains included in the cluster of L. plantarum/L. pentosus/L. paraplantarum and in the cluster of L. paracasei did not shift the type of stereoisomers of lactic acid produced. The change of the type of stereoisomers of lactic acid from the DL-type to the L-type in the presence of sodium acetate was concluded to be species-specific for L. sakei and useful for identification of strains in this species.

DNA, Bacterial↗
PubMed2006

Characterization of a new virulent phage (MLC-A) of Lactobacillus paracasei.

A new virulent bacteriophage (MLC-A) was recently isolated in Argentina from a probiotic dairy product containing a strain of Lactobacillus paracasei. Observation of the lysate with an electron microscope revealed bacteriophage particles with an icosahedral capsid of 57 +/- 2 nm; with a collar and a noncontractile tail of 156 +/- 3 nm terminating with a baseplate to which a tail fiber was attached. Therefore, phage MLC-A belongs to the Siphoviridae family. This phage was able to survive the pasteurization process and was resistant to alcohols and sodium hypochlorite (400 mg/kg). Only peracetic acid could inactivate high-titer suspensions of phages in a short time. The maximum rates of phage adsorption to its host cells were obtained at 30 degrees C with a pH between 5 and 7, and in the presence of calcium or magnesium ions. The host range of phage MLC-A encompassed L. paracasei and Lactobacillus casei strains, but it was not able to infect Lactobacillus rhamnosus or Lactobacillus gasseri strains. One-step growth kinetics of its lytic development revealed latent and burst periods of 30 and 135 min, respectively, with a burst size of about 69 +/- 4 plaque-forming units per infected cell. Phage MLC-A had a distinctive restriction profile when compared with the 2 well-studied Lactobacillus phages, PL-1 and J-1. The genome size of the MLC-A phage was estimated to be approximately 37 kb. This study presents the description of the first phage specific for L. paracasei isolated in Argentina. The isolation of phage MLC-A indicates that, beside lactic acid bacteria starters, probiotic cultures can also be sensitive to virulent phages in industrial processes.

Adsorption↗
PubMed2006

Discrimination of dairy industry isolates of the Lactobacillus casei group.

Lactobacilli are a major part of the microflora of the gut and of many fermented dairy products, and are found in a variety of environments. Lactobacillus casei, Lactobacillus paracasei, Lactobacillus rhamnosus, and Lactobacillus zeae form a closely related taxonomic group within the facultatively heterofermentative lactobacilli. The classification and nomenclature of these bacteria are controversial. In this study, relationships between these species were investigated using type strains and dairy industry isolates examined with DNA-based techniques and conventional carbohydrate use tests. Carbohydrate use patterns gave poor discrimination of some species, but DNA PCR using specific primers targeted to sequences of the 16S rRNA gene discriminated 4 types consistent with the currently recognized species. Pulsed-field agarose gel electrophoresis of chromosomal NotI restriction fragments identified 18 different band patterns from 21 independent Lactobacillus isolates and confirmed the identity of L. casei strains from 2 culture collections (CSCC 5203 and ASCC 290), both representing the type strain of L. casei. Some isolates were reclassified as L. rhamnosus, suggesting that the prevalence of L. rhamnosus as a natural component of the microflora of dairy foods and dairy environments has previously been underestimated. These methods can provide a practical basis for discrimination of the species and identification of individual industrial strains.

Bacteriological Techniques↗
PubMed1983

Lactobacillus acidophilus as a dietary adjunct for milk to aid lactose digestion in humans.

The effect of Lactobacillus acidophilus on lactose utilization of humans was determined by our comparing the amount of hydrogen excreted in their breath after consuming milk containing either 0, 2.5 X 10(6), 2.5 X 10(7), or 2.5 X 10(8) Lactobacillus acidophilus/ml daily for 6 days. Consumption of milk without cells of Lactobacillus acidophilus for 1 wk did not affect lactose utilization. Milk containing either 2.5 X 10(6) or 2.5 X 10(8) Lactobacillus acidophilus/ml improved lactose utilization. However, consumption of milk containing an intermediate 2.5 X 10(7)/ml did not improve utilization based on comparison of group means before and after consuming the test milk. The lack of a significant effect for the latter group of test subjects was probably due to large increases of excreted hydrogen on day 7 as compared to day 0 by two of the six test subjects. The beneficial effect of Lactobacillus acidophilus was immediate and did not require that milk be consumed daily. Improved digestion of lactose was not due to hydrolysis of the lactose prior to consumption, which indicated that the beneficial effect must have occurred in the digestive tract after consumption of milk containing L. acidophilus.

Adult↗
PubMed1994

Absence of cholic acid 7 alpha-dehydroxylase activity in the strains of Lactobacillus and Bifidobacterium.

To investigate the presence of 7 alpha-dehydroxylase activity on bile acids in the bacterial strains of fermented milk products, 46 strains of Lactobacillus casei, Lactobacillus paracasei, Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus gasseri, Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium infantis, Bifidobacterium longum, Lactococcus lactis spp. lactis, and Streptococcus salivarius spp. thermophilus were tested for their ability to produce deoxycholic acid from cholic acid. The production of deoxycholic acid was quantitatively measured by radiochromatographic analysis in anaerobically prepared washed whole resting cells and by HPLC analysis in growing cultures. Resting whole cells from a positive control strain, Eubacterium lentum-like strain c-25, converted 81.7% of .2 mM cholic acid to deoxycholic acid and 3.7% to 7-keto-deoxycholic acid, when the cell suspension was incubated anaerobically at a concentration of 2 mg of protein/ml for 4 h at pH 7.3. However, none of the test strains investigated in this study was able to transform cholic acid under the same conditions. In growing cultures, 91.5% of 150 micrograms/ml of cholic acid was transformed to deoxycholic acid and 1.1% to 7-keto-deoxycholic acid by E. lentum-like c-25 after a 7-d anaerobic incubation. None of the test strains showed production of either deoxycholic acid or 7-keto-deoxycholic acid as growing cultures.

Bifidobacterium↗