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PubMed2006

Effects of extracts of miswak and derum on proliferation of Balb/C 3T3 fibroblasts and viability of cariogenic bacteria.

OBJECTIVES: This study examined the effects of extracts of two chewing sticks on proliferation of fibroblasts and viability of cariogenic bacteria. METHODS: Aqueous extracts of miswak (Salvadora persica; Arak tree) and derum (Juglans regia; walnut tree) were prepared and their effects investigated on growth of Balb/C 3T3 mouse fibroblasts by measuring the mitochondrial succinic dehydrogenase activity. Furthermore, the effects on the viability of various cariogenic bacteria (Streptococcus mutans, Streptococcus salivarius, Lactobacillus casei and Actinomyces viscosus) was also determined. RESULTS: The data revealed that Balb/C 3T3 fibroblasts exposed to aqueous extracts of miswak or derum showed an increase in cell proliferation by 156% and 255%, respectively, in comparison with controls (p < 0.0001). Furthermore, extracts from both miswak and derum had adverse effects on the growth of the cariogenic microorganisms, with derum having significantly greater antimicrobial effects than miswak and at much lower concentrations against all the bacteria tested. The most sensitive organisms were A. viscosus, followed by S. mutans, S. salivarius, with L. casei being the most resistant. CONCLUSION: The results show that aqueous extracts of miswak and derum enhance the growth of fibroblasts and inhibit the growth of cariogenic bacteria, with the derum extract showing greater activity than miswak.

3T3 Cells↗

PubMed2005

Optimization of cholesterol removal by probiotics in the presence of prebiotics by using a response surface method.

Lactobacillus casei ASCC 292 was grown in the presence of six prebiotics, namely, sorbitol, mannitol, maltodextrin, high-amylose maize, fructooligosaccharide (FOS), and inulin, in order to determine the combination of probiotic and prebiotics that would remove the highest level of cholesterol. A first-order model showed that the combination of L. casei ASCC 292, FOS, and maltodextrin was the most efficient for the removal of cholesterol, and the optimum experimental region was developed by using the steepest ascent. This led to the middle points of probiotic (1.70% [wt/vol]), FOS (4.80% [wt/vol]), and maltodextrin (6.80% [wt/vol]) for the development of a central composite design for optimization. Perturbation plot, response surface, and coefficient estimates showed that all three factors had significant quadratic effects on cholesterol removal, with FOS showing the most conspicuous quadratic change. A second-order polynomial regression model estimated that the optimum condition of the factors for cholesterol removal by L. casei ASCC 292 is 1.71% (wt/vol) probiotic, 4.95% (wt/vol) FOS, and 6.62% (wt/vol) maltodextrin. Validation experiments showed that the predicted optimum conditions were more efficient than the high and low levels of the factors and the center points. A response surface method proved reliable for developing the model, optimizing factors, and analyzing interaction effects. Analyses of growth, substrate utilization, growth yield, mean doubling time, and short-chain fatty acid (SCFA) production by the use of quadratic models indicated that cholesterol removal was growth associated. The concentration of L. casei ASCC 292 had the most significant quadratic effect on all responses studied, except for substrate utilization and SCFA production, which were significantly (P < 0.05) influenced by the interactions between the probiotic and both prebiotics, indicating that they were closely associated with the uptake of prebiotics.

Carbohydrate Metabolism↗

PubMed1975

Amino acid analogs. III: New syntheses of monomethyl- and monophenylglutamic acids.

Glutamic acid analogs containing 3- and 4-methyl and 2-, 3-, and 4-phenyl substituents were prepared. The 3- and 4-methyl- and 3- and 4-phenylglutamic acids did not inhibit Plasmodium berghei and were nontoxic to the host (mice) at 640 mg/kg. The five analogs in addition to 2-methlglutamic acid were inactive against Lactobacillus casei at 1000 mug/ml in a defined medium: against Escherichia coli, only 2-methylglutamic acid caused 27% inhibition at 10,000 mug/ml. All six analogs failed to inhibit Aspergillus niger, Aspergillus oryzae, Trichoderma viride, and Myrothecium verrucaria in a defined medium below 10,000 mug/ml.

Animals↗

PubMed1979

Immunological cross-reactivity of oral non-streptococcal bacteria with mammalian tissue.

The presence of cross-reacting antigens between oral non-steptococcal bacteria and human and monkey tissue was investigated by indirect immunofluorescence. Rabbit antisera, prepared against 22 oral bacteria, were incubated with cryostatcut sections of heart, skeletal muscle, brain cord, liver, kidney, and skin. A cell wall antigen of Lactobacillus casei was shared with neuroglial brain cells, and an antigenic component of Propionibacterium acnes was shared with kidney glomeruli. Tissue-reactive antibodies were absorbed from the sera with preparations of both the homologous bacterium and tissue fractions.

Animals↗

PubMed2006

Mucosal immunization with surface-displayed severe acute respiratory syndrome coronavirus spike protein on Lactobacillus casei induces neutralizing antibodies in mice.

Induction of mucosal immunity may be important for preventing SARS-CoV infections. For safe and effective delivery of viral antigens to the mucosal immune system, we have developed a novel surface antigen display system for lactic acid bacteria using the poly-gamma-glutamic acid synthetase A protein (PgsA) of Bacillus subtilis as an anchoring matrix. Recombinant fusion proteins comprised of PgsA and the Spike (S) protein segments SA (residues 2 to 114) and SB (residues 264 to 596) were stably expressed in Lactobacillus casei. Surface localization of the fusion protein was verified by cellular fractionation analyses, immunofluorescence microscopy, and flow cytometry. Oral and nasal inoculations of recombinant L. casei into mice resulted in high levels of serum immunoglobulin G (IgG) and mucosal IgA, as demonstrated by enzyme-linked immunosorbent assays using S protein peptides. More importantly, these antibodies exhibited potent neutralizing activities against severe acute respiratory syndrome (SARS) pseudoviruses. Orally immunized mice mounted a greater neutralizing-antibody response than those immunized intranasally. Three new neutralizing epitopes were identified on the S protein using a peptide neutralization interference assay (residues 291 to 308, 520 to 529, and 564 to 581). These results indicate that mucosal immunization with recombinant L. casei expressing SARS-associated coronavirus S protein on its surface provides an effective means for eliciting protective immune response against the virus.

Amino Acid Sequence↗

PubMed1985

Effect of phenolic compounds, ethyl alcohol, and sodium metabisulphite on the lytic activity of phage PL-1 on a Lactobacillus casei S strain.

The effect of phenolic compounds, ethyl alcohol, and sodium metabisulphite on the lytic activity of virulent bacteriophage PL-1 on a Lactobacillus casei S strain isolated from a lactic acid beverage fermentation was investigated. Catechin, caffeic, and gallic acids, commercially produced red, white, and champagne tannins, ethyl alcohol, and sodium metabisulphite inhibited plaque formation. Catechin, caffeic, and gallic acids were the most effective inhibitors of plaque formation. Commercially supplied oenocyanin was not effective.

Bacteriophages↗

PubMed1996

Chemical composition of the cell wall of lactic acid bacteria and related species.

In order to examine the relationship between biological activities and the cell wall content, the murein type and the teichoic acid of the cell wall from five strains of bacteria were studied. Two of these Lactobacillus casei CRL 431 and L. acidophilus CRL 730, are used in a commercial fermented milk (BIO MILK), which is believed to be beneficial for health. The other strains, Lactococcus lactis CRL 526, Pediococcus pentosaceus CRL 923 and Propionibacterium acidipropionici CRL 1198 were included in order to compare the cell wall structures of active and inactive strains. A method was designed to confirm the amino acids of the peptidoglycan in impure substrates. Four of the studied strains, L. casei, L. acidophilus, L. lactis and P. acidipropionici, contained glycerol teichoic acids. L. casei, L. acidophilus, P. pentosaceus and L. lactis contained A4 alpha type murein, while P. acidipropionici contained A3 gamma type. The capacity of orally administered peptidoglycans of the studied strains to stimulate phagocytosis by mouse peritoneal macrophages was analyzed. Only the PG of L. casei showed this activity. No differences were observed between active and inactive strains with respect to the chemical composition of the peptidoglycan. Therefore the biological activity is unlikely to be due to the peptidoglycan structure.

Animals↗

PubMed1998

Bile salt deconjugation and cholesterol removal from media by Lactobacillus casei.

Lactobacillus casei N19 and E5 and Lactobacillus acidophilus L1 and ATCC 43121 were compared for their ability to deconjugate bile salts and remove cholesterol from MRS broth during growth at pH 6.0 and during growth without pH control. Samples grown without pH control dropped to pH 4.2 to 4.5 during 20 h of incubation, depending on the culture. The plate counts indicated that populations in all cultures were near their maximum numbers after 16 h of growth. The amount of cholesterol removed from the broth was similar for both strains of L. acidophilus grown with and without pH control. However, the strains of L. casei differed significantly in the amount of cholesterol removed during growth with or without pH control. Both cultures of L. casei that were grown at pH 6.0 removed very little cholesterol from the broth, but cells grown without pH control removed up to 60 micrograms of cholesterol/ml. All cultures of both species deconjugated 60 to 90% of the bile salts. Lactobacillus acidophilus L1 was the only culture to demonstrate differences between the two pH treatments in the amount of bile salts deconjugated; however, there was no difference in the amounts of cholesterol removed. These results indicate that most of the cholesterol removal from broth by L. acidophilus was due to assimilation, perhaps by the incorporation of cholesterol into the cellular membrane. Lactobacillus casei most likely removes cholesterol from broth by means of the destabilization of cholesterol micelles and the coprecipitation of the cholesterol with the deconjugated bile salts at pH less than 6.0.

Bile Acids and Salts↗

PubMed2004

Comparison of type 1 and type 2 cytokine production by mononuclear cells cultured with streptococcus mutans and selected other caries bacteria.

A feature of pulpal immune responses is the predominance of type 1 cytokine mRNA under shallow caries and a mixed (type 1/type 2) profile under deep caries. These results prompted an examination of the cytokine profiles induced by bacteria in shallow caries (Streptococcus mutans and Actinomyces viscosus) and deep caries (Lactobacillus casei, Pseudoramibacter alactolyticus, and Prevotella intermedia). All isolates induced interferon-gamma and interleukin-10, whereas interleukin-4 and interleukin-2 titers were low to undetectable. S. mutans was the most potent and persistent interferon-gamma inducer. Differences in interleukin-10 were apparent at low doses but were less dramatic, with L. casei the dominant producer. S. mutans induced substantially more interferon-gamma than interleukin-10 over all doses and time points, suggesting strong type 1 polarization. P. alactolyticus induced significantly more interleukin-10 than interferon-gamma at higher concentrations, suggesting polarization toward type 2. A similar amount of interferon-gamma and interleukin-10 induced by L. casei, A. viscosus, and P. intermedia reflected a mixed profile. A better understanding of pulpal immune response to caries bacteria may enable us to develop an immune system-based pulp therapy in the future.

Actinomyces viscosus↗

PubMed1986

The effect of lowering the pH on the composition and metabolism of a community of nine oral bacteria grown in a chemostat.

Nine oral bacteria, associated with both healthy and diseased sites in the mouth, were grown at D = 0.05 h-1 (mean generation time 13.9 h) in a glucose-limited chemostat. After an initial period of steady-state growth at pH 7.0, pH control was discontinued. The pH then decreased until it stabilized at pH 4.1 after 9 d (16 generations), while the Eh rose from -165 mV to +160 mV. The lowering in pH resulted in the composition and metabolism of the flora being altered and in increased bacterial aggregation. At pH 7.0, 'Streptococcus mitior', Veillonella alcalescens and S. sanguis were most numerous while at pH 4.1 the counts of all bacteria fell except for Lactobacillus casei, which became predominant. The proportions of S. mutans within the community also increased while S. sanguis was recovered only occasionally and Bacteroides intermedius was not detected below pH 4.6. The survival at pH 4.1 of several other species would not have been predicted from earlier pure culture studies. Relative to pH 7.0, the community growing at pH 4.1 produced more lactic acid, washed cells had a greater glycolytic activity over a wider pH range but amino acid metabolism decreased. In general, when pH control was restored, so were the original patterns of metabolism and bacterial counts, except for B. intermedius, which was still not detected. The inverse relationship between S. sanguis and S. mutans, and the increase in proportions of L. casei and S. mutans during growth in a low pH environment parallel observations made in vivo and suggest that the chemostat can be used as a model for microbial behaviour in dental plaque.

Actinomyces↗

PubMed1997

Establishing a model to study the regulation of the lactose operon in Lactobacillus casei.

The chromosomally encoded lactose-specific phosphoenol pyruvate-dependent phosphotransferase system (PTS) has been investigated in Lactobacillus casei ATCC 393 [pLZ15-] and it was considered an excellent system to study the regulation of the lactose operon. This chromosomal operon has been cloned and sequenced, being 99% homologous to that encoded on the plasmid pLZ64. Expression of the lactose operon in different mutants of L. casei ATCC 393 [pLZ15-] and primer extension analysis revealed that it is subject to a dual regulation: (i) glucose repression possibly mediated by CcpA and PTS elements, and (ii) induction by lactose through transcriptional antitermination.

Base Sequence↗

PubMed1985

Lactate dehydrogenase from Streptococcus mutans: purification, characterization, and crossed antigenicity with lactate dehydrogenases from Lactobacillus casei, Actinomyces viscosus, and Streptococcus sanguis.

A cytoplasmic fructose-1,6-diphosphate-dependent lactate dehydrogenase (LDH; EC 1.1.1.27) from Streptococcus mutans OMZ175 was purified to homogeneity as judged by sodium dodecyl sulfate-gel electrophoresis. The purification consisted of ammonium sulfate precipitation of the cytoplasmic fraction, DEAE-Sephacel and Blue-Sepharose CL.6B chromatography, and Sephacryl S200 gel permeation. The catalytic activity of the purified enzyme required the presence of fructose-1,6-diphosphate with a broad optimum between pH 5 and 6.2. The concentration of fructose-1,6-diphosphate required for half-maximal velocity was around 0.02 mM and was affected by the pyruvate concentration. The enzyme seemed to have at least two binding sites for the activator which interact in a cooperative manner. Increasing concentrations of fructose-1,6-diphosphate up to 2 mM enhanced the relative affinity of the enzyme for pyruvate and modified the pyruvate saturation curve from sigmoidal to hyperbolic. The enzyme activity showed also a sigmoidal response to NADH, exhibiting two binding sites for the cofactor with a Hill coefficient of about 1.9. The molecular weight of the native enzyme was 150,000 as determined by gel permeation on Sephacryl S200. Monomers (38,000 daltons) and dimers (85,000 daltons) were observed by sodium dodecyl sulfate-gel electrophoresis; the latter form was dissociated after reduction with 2-mercaptoethanol, and the enzyme could be considered a tetramer. Antibodies obtained against the purified S. mutans OMZ175 LDH cross-reacted with the sodium dodecyl sulfate-dissociated forms of LDHs from different S. mutans serotypes, Streptococcus sanguis OMZ9, Lactobacillus casei ATCC 4646, and Actinomyces viscosus NY 1. A competitive enzyme-linked immunosorbent assay allowed us to detect a very close relationship between the native states of L-LDHs from S. mutans serotypes and S. sanguis. Cross-reactions were also observed with the LDHs from A. viscosus and L. casei, the latter being the least related. A very weak immunological relationship was obtained between the L-LDH from S. mutans OMZ175 and the D-LDH from Lactobacillus leichmannii, whereas no cross-reaction could be detected with mammal LDHs.

Actinomyces↗

PubMed2006

Effects of a Lactobacillus casei synbiotic on serum lipoprotein, intestinal microflora, and organic acids in rats.

The main aim of this study was to evaluate the effectiveness of 3 synbiotic diets: 1) containing Lactobacillus casei ASCC 292 and fructooligosaccharides (LF diet); 2) containing L. casei ASCC 292 and maltodextrin (LM diet); and 3) containing L. casei ASCC 292, fructooligosaccharide, and maltodextrin (LFM diet) to reduce serum cholesterol in male Wistar rats. The effect of the synbiotic diets on intestinal microflora, concentration of organic acids, and the possibility of translocation of lactobacilli were also investigated. The LFM diet lowered serum total cholesterol and triglyceride levels, whereas the LM diet increased serum high-density lipoprotein cholesterol level. However, synbiotic diets did not contribute to a change in low-density lipoprotein cholesterol level compared with the control diet. There was a decrease in the population of staphylococci, bacteroides, Escherichia coli, and total coliforms in most bowel regions with the LFM diet compared with the control (which did not contain any synbiotic). In general, the LFM diet contributed to a higher concentration of lactic acid that may have contributed to the decrease in the population of pathogenic microorganisms compared with the control. Fructooligosaccharide was the preferred substrate for production of acetic acid. Results from this study showed that the synbiotic diet that contained L. casei ASCC 292, fructooligosaccharide, and maltodextrin beneficially altered cholesterol levels and produced a healthier bowel microbial population without translocation of lactobacilli to other organs.

Acetic Acid↗

PubMed1992

Effects of cultured milk products by Lactobacillus and Bifidobacterium species on the secretion of bile acids in hepatocytes and in rats.

Whey preparations prepared from cultured milk by 19 Lactobacillus (2 species) and 20 Bifidobacterium (5 species) strains were examined for the effects of secretion and synthesis of bile acids in primary cultured rat hepatocytes. The stimulating effect of whey preparation on bile acid secretion depended on the species as well as the strains used for milk fermentation. Two strains belonging to L. casei SBT 2230 (LC2230) and B. longum SBT 2912 (BL2912) produced the whey which stimulates both the secretion of bile acid and the activity of cholesterol 7 alpha-hydroxylase, a rate-limiting enzyme for bile acid synthesis. When the cultured products by these two strains were given to rats for 14 days, the products from L. casei (LC2230) were found to stimulate the biliary secretion of bile acids. These results suggest that primary cultured hepatocytes were a useful experimental system as an initial screening for an active principle modulating cholesterol metabolism.

Animals↗

PubMed1983

m- And p-halobenzoyl derivatives of p-halo-DL-phenylalanine as inhibitors in a microbial antitumor prescreen.

Meta- and p-halobenzoyl-p-halo-phenylalanine compounds were prepared and tested for growth-inhibitory activity in a Lactobacillus casei system. The activity of 13 of the most active of these compounds, reported here, was greater than that of any other acyl derivatives of amino acid analogs previously studied in this system and was from 2 to 8 times greater than that of 6-mercaptopurine, a known antitumor agent.

Antineoplastic Agents↗

PubMed2002

Lactobacillus species is more cytotoxic to human bladder cancer cells than Mycobacterium Bovis (bacillus Calmette-Guerin).

PURPOSE: We determined if Lactobacillus species has growth inhibitory effects in human bladder cancer cell lines and how this effect compares with the known effects of Mycobacterium bovis, that is bacillus Calmette-Guerin (BCG). MATERIALS AND METHODS: The growth of MGH and RT112 cells were determined by cell counts after 24, 48 and 72 hours of exposure to L. casei strain Shirota (Yakult, Singapore) or L. rhamnosus strain GG (National Collection of Industrial and Marine Bacteria, Ltd., Aberdeen, Scotland) (1 x 10 and 1 x 10 cfu) or BCG (1 x 10 cfu) in the presence and absence of streptomycin. Annexin-V was used to monitor the presence of pre-apoptotic cells. RESULTS: L. rhamnosus GG inhibited MGH proliferation and it was cytotoxic to RT112 cells (p <0.05). L. casei Shirota was cytotoxic to the 2 cell lines (p <0.05). BCG had a similar cytotoxic effect in MGH cells as Lactobacillus species but was not as effective in RT112 cells. Streptomycin abrogated the cytotoxic effect of Lactobacillus species but not that of BCG. Cytotoxic activity was not found in Lactobacilli culture supernates but it was induced in the presence of mammalian cells. L. rhamnosus GG induced apoptosis in RT112 but not in MGH cells. No apoptotic cells were detected after treatment with L. casei Shirota. CONCLUSIONS: Lactobacillus species induced cytotoxic effects in bladder cancer cells. Unlike BCG, it requires bacterial protein synthesis. Like BCG, L. casei Shirota induces cell death primarily via necrosis. The cytoxicity of these lactobacilli in bladder cancer cells raises the possibility of using this species of bacteria as intravesical agents for treating bladder cancer.

BCG Vaccine↗

PubMed1990

Prevention of gastrointestinal infection using immunobiological methods with milk fermented with Lactobacillus casei and Lactobacillus acidophilus.

The protective effect of feeding milk fermented with a mixture of Lactobacillus casei sp. and Lb. acidophilus sp. against Salmonella typhimurium infection in mice was compared with that obtained feeding milks fermented with these microorganisms individually. The survival rate obtained after oral infection with Sal. typhimurium was 100% in mice pretreated by feeding during 8 d with the mixture of Lb. casei and Lb. acidophilus fermented milks. Similar treatments with the individual milks were ineffective. Moreover, mice became more susceptible to infection with Sal. typhimurium after such treatment. The colonization of liver and spleen with the pathogen was markedly inhibited by the pretreatment with the mixture of fermented milk, while such inhibition was not observed using the Lb. casei and Lb. acidophilus milks. The highest levels of anti-salmonellae antibodies in serum and in intestinal fluid were found in the group of mice fed with the mixture and with Lb. casei fermented milk respectively. However, this latter milk was not effective in protecting against Sal. typhimurium. When the mice were first infected with Sal. typhimurium and then fed with the mixture of fermented milks, pathogen colonization was not prevented. The results suggest that the augmentation of resistance to salmonellae caused by the treatment with Lb. casei- + Lb. acidophilus-fermented milk was due to the anti-salmonellae protective immunity mainly mediated by the mucosal tissue. Milk fermented with this mixture could be used as an immunobiological method to prevent gastrointestinal infection.

Animals↗

PubMed2004

Encapsulated lactic acid bacteria for control of malolactic fermentation in wine.

The kinetics of both malolactic fermentation in Chardonnay wine by encapsulating Lactobacillus casei cells in pectate gel and lyophilized Oenococcus oeni culture has been carried out. The influence of acidity, sulfur dioxide content, and organic acid content on the malolactic activity of the bacteria has been controlled. Encapsulated bacteria degraded 30%, of malic acid in white wine, deacidifying it from pH 3.15 to 3.40, whereas the lyophilized culture degraded 48% of malic acid, deacidifying from pH 3.15 to 3.60. The degree of conversion of malic acid in wine by the encapsulated cells was twice as high as that obtained by the free Lactobacillus casei cells. The operational stability of calcium pectate gel capsules was 6 months. It has been proved that the encapsulated biocatalyst increases the rate of fermentation, and induces the fermentation to take place at high ethanol concentrations. The proposed encapsulated biocatalyst is an attractive material for industrial applications in continuous winemaking processes.

Capsules↗