Probiotic Strains Lactobacillus Acidophilus Research Articles

Advantageous Direct Quantification of Viable Closely Related Probiotics in Petit-Suisse Cheeses under In Vitro Gastrointestinal Conditions by Propidium Monoazide - qPCR

Species-specific Quantitative Real Time PCR (qPCR) alone and combined with the use of propidium monoazide (PMA) were used along with the plate count method to evaluate the survival of the probiotic strains Lactobacillus acidophilus La-5 and Bifidobacterium animalis subsp. lactis Bb-12, and the bacteriocinogenic and potentially probiotic strain Lactobacillus sakei subsp. sakei 2a in synbiotic (F1) and probiotic (F2) petit-suisse cheeses exposed throughout shelf-life to in vitro simulated gastrointestinal tract conditions. The three strains studied showed a reduction in their viability after the 6 h assay. Bb-12 displayed the highest survival capacity, above 72.6 and 74.6% of the initial populations, respectively, by plate count and PMA-qPCR, maintaining population levels in the range or above 6 log CFU/g. The prebiotic mix of inulin and FOS did not offer any additional protection for the strains against the simulated gastrointestinal environment. The microorganisms' populations were comparable among the three methods at the initial time of the assay, confirming the presence of mainly viable and culturable cells. However, with the intensification of the stress induced throughout the various stages of the in vitro test, the differences among the methods increased. The qPCR was not a reliable enumeration method for the quantification of intact bacterial populations, mixed with large numbers of injured and dead bacteria, as confirmed by the scanning electron microscopy results. Furthermore, bacteria plate counts were much lower (P<0.05) than with the PMA-qPCR method, suggesting the accumulation of stressed or dead microorganisms unable to form colonies. The use of PMA overcame the qPCR inability to differentiate between dead and alive cells. The combination of PMA and species-specific qPCR in this study allowed a quick and unequivocal way of enumeration of viable closely related species incorporated into probiotic and synbiotic petit-suisse cheeses and under stress conditions.

Optimization of Spray-Drying Process Conditions for the Production of Maximally Viable Microencapsulated L. acidophilus NCIMB 701748

Inrecent years, the use of spray drying for the production of anhydrobiotics has gained the interest of functional food manufacturers, mainly due to cost efficiencies and enhanced product and process flexibility (e.g., enhanced shelf life). In the present work, spray-drying conditions (air inlet temperature and feed flow rate) were optimized for the microencapsulation of the thermo sensitive probiotic lactobacilli strains Lactobacillus acidophilus stabilized in a 60:20:20 (w/w) maltodextrin: whey protein concentrate: D-glucose carrier. A 23 full-factorial experimental design was constructed with air inlet temperature (120, 140, and 160°C) and feed flow rate (6, 7.5, and 9.0 mL/min) as the independent variables and total viable counts (TVC), water activity (a w ), and cyclone recovery (CR) defined as the dependent variables. The increase in air inlet temperature from 120 to 160°C induced a significant (p < 0.001) reduction in the TVC from 9.02 to 7.20 log cfu/g, which corresponds to a97.5% loss of the L. acidophilus viable counts. On the other hand, the increase in the feed flow rate from 6 to 7.5 mL/min significantly reduced (p < 0.001) the heat-induced viability loss. A further increase in the feeding rate did not further modify the achieved thermo protection, and a detrimental impact of cyclone recovery (reduction) and water activity (increase) of the powder was observed. Using pruned quadratic mathematical models, the optimum spray-drying conditions for the production of maximally viable microencapsulated L. acidophilus were 133.34°C and 7.14 mL/min. The physicochemical and structural characteristics of the powders produced were acceptable for application with regards to residual water content, particles mean size, and thermo physical properties to ensure appropriate storage stability under room temperature conditions, with a low inactivation rate of L. acidophilus. Microcapsules appeared partially collapsed by scanning electron microscope with a spherical shape with surface concavities.

Fermentation of coconut water by probiotic strains Lactobacillus acidophilus L10 and Lactobacillus casei L26

Coconut water is becoming an increasingly popular beverage and sports drink in tropical countries due to its high mineral content. Probiotic fermentation of coconut water would provide consumers with a novel probiotic beverage which can provide both hydration and probiotic benefits. The aim of this study was to assess the growth, survival and fermentation performance of two probiotic bacteria in coconut water. Lactobacillus acidophilus L10 and L. casei L26 grew well in coconut water and showed similar growth patterns. The viable cell count of the two probiotic cultures reached approximately 108 CFU/ml after 2 days fermentation at 37 °C and maintained approximately107–108 CFU/ml after 26 days at 4 °C. Changes in total soluble solids (oBrix), pH, sugars, organic acids and minerals were similar between the two probiotic cultures, except for fructose, glucose, copper, phosphorus and lactic, acetic and malic acids. There were significant variations between the two cultures in their ability to produce and consume these compounds. L. acidophilus produced higher amounts of 2-heptanone, 2-nonanone, benzaldehyde, 2-heptanol, 2-nonanol, δ-octalactone and δ-dodecalactone, whereas L. casei produced higher amounts of acetic acid, diacetyl, acetoin, δ-decalactone, 3-methyl-3-buten-1-ol, linalool, 1-octanol, p-tolualdehyde and ethyl 2-hydroxypropanoate. There was no substantial change in mineral content. These results suggest the feasibility of fermenting coconut water into a probiotic beverage, especially for sports nutrition, with the dual benefits of electrolytes and probiotics.

3T3-L1 전지방세포에서 발효 삼정환의 지방 분화 억제 효과

본 연구에서는 3T3-L1 전지방세포를 이용하여 발효 삼정환의 지방 분화 억제 효과를 확인하고자 하였다. 삼정환을 5가지 주요 유산균으로 각각 발효시킨 후, Oil Red O 염색법으로 지방세포 분화 억제 여부를 알아보고, 이의 기전을 알기 위해서 지방생성에 핵심적인 역할을 하는 transcription factor 및 지질 조절 효소의 유전자 발현량을 비교하여 보았다. Oil Red O 염색 분석에서는 Lactobacillus plantarum, Enterococcus faecium으로 발효한 삼정환에서 지방구 수의 감소를 확인할 수 있었다. 또한 transcription factor로 C/EPBα, PPARγ, UCP-2 및 콜레스테롤 조절과 관련된 효소인 HMG-CoA reductase의 4가지 유전자 발현 정도를 분석하였는데, 발효시키지 않은 삼정환의 경우 농도가 100 μL/mL 이상일 때 네 가지 항목에서 억제 효과를 나타냈으며, 발효시켰을 때는 유산균의 종류에 따라 효과 억제효과가 있었는데, Lactobacillus plantarum으로 발효한 삼정환이 효과가 가장 좋은 것으로 나타났다. Lactobacillus plantarum으로 발효한 삼정환은 동일 농도의 발효하지 않은 삼정환과 비교했을 때, Oil Red O 실험에서 염색된 지방구 수가 더욱 감소하였으며, PPARγ, UCP-2, HMG-CoA reductase의 경우 농도가 200 μL/mL일 때 각각 35%, 57%, 54%로 5가지 발효 삼정환 중 가장 높은 억제율을 나타내었다. 이에 지방분화 억제 효과를 가진 삼정환을 발효시키면 그 효과가 더욱 증가하는 것으로 나타났는데, 특히 Lactobacillus plantarum 으로 발효한 삼정환은 PPARγ, UCP-2, HMG-CoA reduc tase의 유전자 발현조절을 통해 지방 분화를 억제시키는 것으로 밝혀져 발효 삼정환은 항비만 혹은 항고지혈증 약물로 개발 가능성이 있는 것으로 사료된다.

Evaluation of Some Factors with Significant Influence on Functionality and Viability of Probiotic Strains LA-5 ® and L. Casei 431 ® in Multiple Starter Cultures in Mesophilic Fermented Milk

Abstract. For a very long time, probiotics have been selected on the basis of their suitability to food’s environment and technological procedures, as well as survival ability in vitro and also in vivo. These criteria are still used. The aim of this study was to select, using the Plakett-Burman design of experiments model, of three significant factors, which influence the multiplication ability and viability of probiotic strains Lactobacillus acidophilus (commercial code LA-5®) and Lactobacillus casei subsp. paracasei (commercial code L. casei 431®) in fermented mesophilic milk product (commercial named Sana) obtained by fermentation with a multiple culture with mesophilic lactic starter Flora Danica Chr. Hansen commercial starters (Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. diacetylactis and Leuconostoc mesenteroides subsp. cremoris). By statistical analysis the most important factors (independent variables) with influence on the probiotic bacteria were selected for the optimized. These are the temperature of fermentation; the ratio between probiotic strains and Flora Danica and the addition of prebiotic Fagopyrum esculentum flour. In the future experiments the optimum values of these parameters will be optimized by using response surface methodology, in order to establish the conditions in which can be obtain the mesophilic fermented milk products with probiotic action in vivo.Â

The prebiotic source influences the growth, biochemical features and survival under simulated gastrointestinal conditions of the probiotic Lactobacillus acidophilus

The viability of the probiotic strain Lactobacillus acidophilus DSM 20079, after its passage through the simulated gastric and pancreatic juices, was evaluated as function of its pre-growth in a medium containing the known prebiotics pectin or inulin, and was compared to glucose used as control. The presence of pectin or inulin did not affect the growth (12.11log10 colony forming units/mL and 12.08log10 colony forming units/mL for pectin and inulin respectively versus 12.22log10 colony forming units/mL obtained for glucose). Pectin and inulin, in contrast to glucose, induced cell stress resistance against gastrointestinal juices (Δlog10 1 and 2 colony forming units/mL respectively, versus Δlog10 4.5 for glucose). The data were confirmed by the analysis of the protein pattern following stress treatments which, in the case of microbial cells grown with glucose, revealed a relevant protein degradation after the double passage through simulated gastric and intestinal juices. An impressive metabolic change, as function of the growth conditions, was demonstrated by analyzing the proteomic profile with a μ-2DE system, used herein for the first time as evaluation tool of prebiotic–probiotic interactions. The analysis revealed a different pH protein distribution that was mostly acidic in the presence of pectin and neutral-alkaline in the presence of inulin. Both prebiotics stimulated the production of butyrate, a relevant healthy bio-molecule not detectable in the presence of glucose, that was measured by HPLC analysis to be 14.5 fold higher after growth in the presence of inulin, as compared to pectin. Three specific proteins were detected at pH 6 after growth in the presence of pectin or inulin. They could be correlated to the stress resistance and/or to the production of butyrate, the common phenotypic characteristics induced in the bacterial strain by the two prebiotics.

The effect of a probiotic strain (Lactobacillus acidophilus) on the plaque formation of oral Streptococci

The objective of this study was to investigate the ability of biofilm formation among mutans and non mutans oral streptococci and to determine the effect of Lactobacillus acidophilus DSM 20079 as a probiotic strain on the adhesion of selected streptococcal strains on the surfaces. The sample comprised 40 isolates of oral streptococci from dental plaque and caries of volunteer persons. Streptococcus mutans ATCC35668 (no24) was as an standard strain. The probiotic strain was Lactobacillus acidophilus DSM 20079. The ability of biofilm formation was investigated with colorimetric method and the strongest isolates were selected. Then the effect of probiotic strain on the adhesion of streptococci isolates was determined in polystyrene microtiter plate simultaneously and 30 minutes before streptococci entrance to the system. The results showed that 42% of mutans streptococci were strongly adherent (SA) and in non mutans streptococci, only 23.5% of isolates were found strongly adherent. The strong biofilm forming bacterium isolated was Streptococcus mutans strain22. In the next step, in the presence of probiotic strain the streptococcal adhesion were reduced, and this reduction was non significantly stronger if the probiotic strain was inoculated to the system before the oral bacteria. The Lactobacillus acidophilus had more effect on adherence of mutans streptococci than non mutans streptococci with significant difference (p < 0.05). Adhesion reduction is likely due to bacterial interactions and colonization of adhesion sites with probiotic strain before the presence of streptococci. Adhesion reduction can be an effective way on decreasing cariogenic potential of oral streptococci.

Effect of Green Tea and EGCG on the Growth Rate and Cell Density of the Probiotic Bacteria Lactobacillus acidophilus and Lactobacillus gasseri

Green tea and probiotic bacteria have been reported to have beneficial health effects individually. The purpose of this study was to determine if green tea (GT) or epigallocatechin‐3‐gallate (EGCG), the main flavonoid component of GT, would stimulate the growth rate and increase the cell density in planktonic cultures of the probiotic bacterial strains Lactobacillus acidophilus NCFM (L. acid.) and Lactobacillus gasseri ATCC 33323 (L. gas.). Aqueous GT and EGCG extracts were prepared and matched for total phenol content. Growth rate was determined using a 96‐well microtiter plate assay. Cell density was assessed via optical density at 600nm. GT (1, 2, 10, 20, 30 and 40%) and EGCG (1, 2 and 10%) enhanced the maximum specific growth rate (MSGR) of L. acid. vs. the control. GT (4, 10, 20, 30, and 40%) and EGCG (1, 2, 4, 10, and 20%) also enhanced the MSGR of L. gas. relative to the control. GT (10 and 30%) and EGCG (1% only) increased the cell density of both L. acid. and L. gas. relative to the control. In summary, in preliminary results, GT and EGCG increased the growth rate and final cell densities of both L. acid. and L. gas., suggesting that combinations of probiotic cultures with tea components may promote survival, growth or activity in the gastrointestinal tract. This project was supported by North Carolina State University, the NC Dairy Foundation, and the Southeast Dairy Foods Research Center.

Proteolytic activity of three probiotic strains in semi-hard cheese as single and mixed cultures: Lactobacillus acidophilus, Lactobacillus paracasei and Bifidobacterium lactis

The influence of three probiotic strains ( Lactobacillus acidophilus, Lactobacillus paracasei and Bifidobacterium lactis) in semi-hard cheese proteolysis patterns was assessed. Probiotics were inoculated both as single cultures and as a three-strain mix, and added to milk either after a pre-incubation step or directly to the vat. B. lactis did not show any effect on proteolysis of cheeses, while L. paracasei showed limited impact at the end of the ripening. In contrast, L. acidophilus significantly influenced secondary proteolysis from the beginning of ripening, causing an increase in the levels of small nitrogen-containing compounds and free amino acids and changes in the peptide profiles. The effect of Lactobacillus acidophilus on peptidolysis was more noticeable when it was added to cheese–milk after pre-incubation in an enriched milk fat substrate. Similar results obtained with the three-strain mixed culture, suggesting that L. acidophilus played a major role in secondary proteolysis of probiotic cheeses in this trial.

Effect of Probiotic Strains Lactobacillus acidophilus LAFTI L10 and Lactobacillus paracasei LAFTI L26 on Systemic Immune Functions and Bacterial Translocation in Mice

The immunostimulatory effects of Lactobacillus acidophilus LAFTI L10 and Lactobacillus paracasei LAFTI L26 were evaluated to determine their probiotic properties for functional food applications. Mice were given oral doses of either L. acidophilus L10 or L. paracasei L26 (108 CFU/50 μl/day), and the effects on immune responses and bacterial translocation were assessed after the 14-day feeding trial. The proliferative responses of splenocytes to concanavalin A and lipopolysaccharide were significantly higher in mice fed L. acidophilus. Concanavalin A–induced splenocyte proliferative responses increased significantly in mice fed L. paracasei. Interleukin 10 and interferon γ production from the splenocytes stimulated with concanavalin A were enhanced in mice fed L. acidophilus or L. paracasei. The phagocytic activity of the peritoneal macrophages was significantly higher in mice fed either L. acidophilus or L. paracasei compared with control mice. In mice fed L. acidophilus or L. paracasei, the bacterial translocation of Lactobacillus spp. and total anaerobes to Peyer's patches and mesenteric lymph nodes was modulated compared with that in the control mice. Furthermore, there was no indication of disruption of intestinal mucosal integrity and thus no bacterial translocation to spleen, liver, or blood in mice fed either L. acidophilus or L. paracasei. The results of this study indicate that L. acidophilus and L. paracasei are potential enhancers of systemic immunity and are nonpathogenic, as suggested by their bacterial translocation profiles in healthy mice.

Effects of Lactobacillus acidophilus D2/CSL on laying hen performance

In order to evaluate the effects of dietary addition of probiotic strain Lactobacillus acidophilus D2/CSL on hen performance and egg quality, 160 commercial Hy-Line Brown pullets, 17 weeks old, were divided in control group (C) (N=80) and treated group (T) (N=80), with 4 alternate replicates of 20 animals each per group. C was fed with a “standard diet”, whereas the T group received the same diet with an inclusion of 1x109 CFU kg-1 of Lactobacillus acidophilus D2/CSL (freeze dried cells). The experimental trial lasted 39 weeks after one week of acclimatization.Hen performance and egg quality (egg production, FCR, egg specific gravity, shell thickness, Haugh Units) were recorded. The results show a higher overall egg production (P<0.01) and better FCR (Kg feed intake/Kg saleable eggs) (P<0.05) in the T birds, but no statistically significant differences were observed in egg weight. The eggs from the T birds were characterized by a higher specific gravity (ESG) (P<0.01) and albumen viscosity (Haugh Units) (P<0.05). No significant differences in egg shell thickness were recorded. In conclusion, Lactobacillus acidophilus D2/CSL improved some important parameters in laying hen performance and egg quality.

Characterization and molecular cloning of a heterodimeric β-galactosidase from the probiotic strainLactobacillus acidophilusR22

Beta-galactosidase from the probiotic strain Lactobacillus acidophilus R22 was purified to apparent homogeneity by ammonium sulphate fractionation, hydrophobic interaction, and affinity chromatography. The enzyme is a heterodimer consisting of two subunits of 35 and 72 kDa, as determined by gel electrophoresis. The optimum temperature of beta-galactosidase activity was 55 degrees C (10-min assay) and the range of pH 6.5-8, respectively, for both o-nitrophenyl-beta-D-galactopyranoside (oNPG) and lactose hydrolysis. The Km and Vmax values for lactose and oNPG were 4.04+/-0.26 mM, 28.8+/-0.2 micromol D-glucose released per min per mg protein, and 0.73+/-0.07 mM, 361+/-12 micromol o-nitrophenol released per min per mg protein, respectively. The enzyme was inhibited by high concentrations of oNPG with Ki,s=31.7+/-3.5 mM. The enzyme showed no specific requirements for metal ions, with the exception of Mg2+, which enhanced both activity and stability. The genes encoding this heterodimeric enzyme, lacL and lacM, were cloned, and compared with other beta-galactosidases from lactobacilli. Beta-galactosidase from L. acidophilus was used for the synthesis of prebiotic galacto-oligosaccharides (GOS) from lactose, with the maximum GOS yield of 38.5% of total sugars at about 75% lactose conversion.

Tetracycline susceptibility of the ingested Lactobacillus acidophilus LaCH-5 and Bifidobacterium animalis subsp. lactis Bb-12 strains during antibiotic/probiotic intervention

We investigated the effects of oral therapy with doxycycline, a tetracycline group antibiotic, on the gastrointestinal (GI) survival and tetracycline susceptibility of probiotic strains Lactobacillus acidophilus LaCH-5 and Bifidobacterium animalis subsp. lactis Bb-12. In addition, the influence of doxycycline therapy on the diversity of the predominant faecal microbiota was evaluated by polymerase chain reaction—denaturing gradient gel electrophoresis (PCR-DGGE). Faecal samples from the antibiotic group (receiving antibiotics and probiotics) and the control group (receiving probiotics only) were analysed for anaerobically and aerobically growing bacteria, bifidobacteria and lactic acid bacteria as well as for the dominant microbiota. Although doxycycline consumption did not have a large impact on GI survival of the probiotics, it had a detrimental effect on the bifidobacteria and on the diversity of the dominant faecal microbiota. A higher proportion of tetracycline-resistant anaerobically growing bacteria and bifidobacteria was detected in the antibiotic group than in the control group. Several antibiotic group subjects had faecal B. animalis subsp. lactis Bb-12-like isolates with reduced tetracycline susceptibility. This was unlikely to be due to the acquisition of novel tetracycline resistance determinants, since only tet(W), which is also present in the ingested B. animalis subsp. lactis Bb-12, was found in the resistant isolates. Thus, concomitant ingestion of probiotic L. acidophilus LaCH-5 and B. animalis subsp . lactis Bb-12 with the antibiotic did not generate a safety risk regarding the possible GI transfer of tetracycline resistance genes to the ingested strains.

Effects of Lactobacillus acidophilus DSM13241 as a probiotic in healthy adult cats

To evaluate the effect of dietary supplementation with the probiotic strain Lactobacillus acidophilus DSM13241 in healthy adult cats. 15 adult cats. Cats were fed a nutritionally complete dry food for 5 weeks. Fecal character was assessed daily, and a single fecal sample and 3-mL blood sample were collected for bacterial enumeration and hematologic analysis, respectively. Cats were then fed the same diet supplemented with L acidophilus DSM13241 (2 x 10(8) CFU/d) for 4.5 weeks. Repeat fecal and hematologic measurements were taken prior to the return to control diet for a 4-week period. The probiotic species was recovered from feces, demonstrating survival through the feline gastrointestinal tract. Probiotic supplementation was associated with increased numbers of beneficial Lactobacillus and L acidophilus groups in feces and decreased numbers of Clostridium spp and Enterococcus faecalis, indicating an altered bacterial balance in the gastrointestinal tract microflora. Fecal pH was also decreased suggesting a colonic environment selective for the beneficial lactic acid bacterial population. Systemic and immunomodulatory effects were associated with administration of L acidophilus DSM13241 including altered cell numbers within WBC subsets and enhanced phagocytic capacity in the peripheral granulocyte population. In addition, plasma endotoxin concentrations were decreased during probiotic feeding, and RBCs had a decreased susceptibility to osmotic pressure. Probiotic strain L acidophilus DSM13241 fed at 2 x 10(8) CFU/d can alter the balance of gastrointestinal microflora in healthy cats. Furthermore, administration of this probiotic results in beneficial systemic and immunomodulatory effects in cats.

Importance of S-layer proteins in probiotic activity of Lactobacillus acidophilus M92

To investigate the functional role of surface layer proteins (S-layer) in probiotic strain Lactobacillus acidophilus M92, especially its influence on adhesiveness to mouse ileal epithelial cells. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of cell surface proteins revealed the presence of potential surface layer (S-layer) proteins, ca at 45 kDa in L. acidophilus M92. Southern blot with pBK1 plasmid, containing slpA gene, gave a positive signal, suggesting that L. acidophilus M92 has a slpA gene coding for the S-layer proteins. S-layer proteins of this strain are present during all phases of growth. The S-layer proteins appeared when cells treated with 5 mol l(-1) LiCl were allowed to grow again. Removal of the S-layer proteins reduced adhesion of L. acidophilus M92 to mouse ileal epithelial cells. Furthermore, the viability of cells without S-layer were reduced in simulated gastric juice at low pH range (2, 2.5, 3) and simulated pancreatic juice with bile salts (1.5 and 3 g l(-1)). S-layer proteins of L. acidophilus M92 were resistant to pepsin and pancreatin, in contrast, the treatment with proteinase K led to a significant proteolysis of the S-layer proteins. These results demonstrated functional role of S-layer; it is responsible for adhesiveness of Lactobacillus acidophilus M92 to mouse ileal epithelial cells and has a protective role for this strain. S-layer proteins have an important role in the establishment of probiotic strain Lactobacillus acidophilus M92 in the gastrointestinal tract.

The effect of bile salts on survival and morphology of a potential probiotic strain Lactobacillus acidophilus M92

Bile tolerance is an important criterion in the selection of microbial strains for probiotic use. The survival and morphological changes of a potential probiotic strain, Lactobacillus acidophilus M92, in the presence of bile salts were examined. Lactobacillus acidophilus M92 has shown a satisfactory degree of tolerance against oxgall and individual bile salts tested, especially to taurocholate. The higher resistance of L. acidophilus M92 against taurine-conjugated bile salts relative to deconjugated and glycine-conjugated bile salts was attributed to its reaction to the stronger acidity of the former. Furthermore, bile salt hydrolase (BSH) was active when L. acidophilus M92 was grown in the presence of sodium taurocholate. The rate of BSH activity was highest at the exponential growth phase. It was hypothesised that BSH activity may be important for the bile salt resistance of this strain. The colonial and cellular morphology may also be a valuable parameter in the selection of bile salt-resistant Lactobacillus strains for probiotic use. Smooth (S) and rough (R) colonies, appeared in the original L. acidophilus M92 bacterial culture and demonstrated a different degree of bile tolerance. Rough colonies were more sensitive to bile salts than smooth ones. The R colony cells assumed a round form, probably induced by gaps in the cell wall caused by the cytotoxicity of glycodeoxycholate.