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Surinder Baines - One of the best experts on this subject based on the ideXlab platform.
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In vitro investigation of the effect of dairy propionibacteria on rumen pH, lactic acid and volatile fatty acids
Journal of Integrative Agriculture, 2017Co-Authors: Jianbiao Luo, Chaminda Senaka Ranadheera, Stuart King, Craig Evans, Surinder BainesAbstract:Abstract Ruminal acidosis is a prevalent disorder in ruminants such as dairy cows and feedlot beef cattle, caused primarily by the inclusion of a high percentage of readily fermentable concentrates in the diet. The disorder presents as an accumulation of lactic acid, a decrease of pH in the rumen and a subsequent imbalance of the rumen fermentation process with detrimental impacts on the animal's health and productivity. Dairy propionibacteria, a group of bacteria characterised by utilization of lactic acid as the favoured carbon source, with propionic acid produced as a by-product, were evaluated in this study as potential direct-fed microbials for use in controlling ruminal acidosis. Acidosis was simulated by introduction of high concentrations of lactic acid into rumen fluid samples and a multi-strain in vitro analysis was conducted, whereby changes in pH and lactic acid metabolism were compared in identical acidified rumen samples, following inoculation with various propionibacteria. This was followed by a study to evaluate the effect of bacterial inoculation dosage on acid metabolism. The results indicated that lactic acid levels in the rumen fluid were significantly reduced, and propionic acid and acetic acid concentrations both significantly increased, following addition of propionibacteria. Significant ‘between strains’ differences were observed, with Propionibacterium acidopropionici 341, Propionibacterium freudenreichii CSCC 2207, Propionibacterium jensenii NCFB 572 and P. jensenii 702 each producing more rapid reduction of lactic acid concentration than P. freudenreichii CSCC 2206, P. acidopropionici ATCC 25562 and Propionibacterium thoenii ATCC 4874. Furthermore, the efficacy of this application was dosage related, with the rates of reduction in lactic acid levels and production of propionic acid, both significantly greater for the higher (10 10 cfu mL −1 ) compared with lower (10 5 cfu mL −1 ) dosage inoculation. The results confirmed that the introduction of propionibacteria could promote more rapid reduction of lactic acid levels than would occur without their addition, demonstrating their potential in controlling ruminal acidosis.
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Co-culturing of probiotics influences the microbial and physico-chemical properties but not sensory quality of fermented dairy drink made from goats’ milk
Small Ruminant Research, 2016Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Seven different types of fermented drinking milk were made from goats’ milk using various culture compositions of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel putative probiotic Propionibacterium jensenii 702. Probiotic viability, physico-chemical and sensory properties of fermented milk were measured during 3 weeks of storage at 4 °C. All three probiotics were able to maintain high viability (>107 cfu mL−1) during fermentation and subsequent storage regardless of the culture composition in goats’ milk without major antagonistic effects. Acidity of all fermented milk samples increased during storage, however there were no significant differences among preparations for organoleptic properties. Generally, lower sensory acceptability was recorded for the samples stored for 3 weeks than the respective fresh products
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Microencapsulation of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 by spray drying in goat's milk
Small Ruminant Research, 2015Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:A mixture of probiotic Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel potential probiotic Propionibacterium jensenii 702 was resuspended in reconstituted (20% w/v) goat's milk, spray dried in a mini spray dryer (inlet temperature=195°C and outlet temperature=85°C) and the spray dried powder was stored in air tight glass jars at 4°C and 30°C for 24 weeks. Powder quality and probiotic viability after spray drying and subsequent storage were measured. Spray drying probiotics in reconstituted goat's milk resulted in a significant reduction in the viability of all three probiotics. However, all three probiotics were able to maintain satisfactory viability levels (10⁶-10⁸cfu/g) after spray drying. While storage temperature did not appear to have a significant effect on moisture content, the viability of all three strains declined dramatically when stored at 30°C but lactobacilli and propionibacteria remained virtually unaffected under storage at 4°C, satisfying recommendations regarding the level of viable cells in probiotic foods
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Effect of dairy probiotic combinations on in vitro gastrointestinal tolerance, intestinal epithelial cell adhesion and cytokine secretion
Journal of Functional Foods, 2014Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Gastrointestinal tolerance, adhesion to intestinal epithelium and immunomodulation are critical factors in maintaining probiotic efficacy. Seven different types of fermented milk were made from goat's milk using various culture compositions of three probiotics: Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 and in vitro gastrointestinal tolerance, adhesion ability and stimulation of cytokine production by probiotics were evaluated. All probiotics and combinations demonstrated significantly lower viability after exposure to simulated gastric (pH 2.0) and intestinal (with 0.3% bile, pH 8.0) fluids (p
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Probiotic viability and physico-chemical and sensory properties of plain and stirred fruit yogurts made from goat's milk.
Food chemistry, 2012Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Abstract Probiotic plain and stirred fruit yogurts were made from goat’s milk using bacterial cultures comprising, Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702. The products were stored at 4 °C for 4 weeks, during which time the viability of the yogurt starter culture and probiotic bacteria was analysed weekly. P. jensenii 702 demonstrated the highest viability (108cfu/g) in all types of yogurt throughout the storage period, while the viability of the bifidobacteria (∼107 cfu/g) also remained above the minimum therapeutic level. The viability of L. acidophilus LA-5 fell below 106 cfu/g in yogurts, however, the addition of fruit juice appeared to support the viability of lactobacilli, with higher microorganism numbers observed in fruit yogurts than in plain yogurt throughout the shelf life. Addition of fruit juice significantly increased the syneresis, and decreased viscosity and water holding capacity of yogurts (p
Michelle C. Adams - One of the best experts on this subject based on the ideXlab platform.
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Co-culturing of probiotics influences the microbial and physico-chemical properties but not sensory quality of fermented dairy drink made from goats’ milk
Small Ruminant Research, 2016Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Seven different types of fermented drinking milk were made from goats’ milk using various culture compositions of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel putative probiotic Propionibacterium jensenii 702. Probiotic viability, physico-chemical and sensory properties of fermented milk were measured during 3 weeks of storage at 4 °C. All three probiotics were able to maintain high viability (>107 cfu mL−1) during fermentation and subsequent storage regardless of the culture composition in goats’ milk without major antagonistic effects. Acidity of all fermented milk samples increased during storage, however there were no significant differences among preparations for organoleptic properties. Generally, lower sensory acceptability was recorded for the samples stored for 3 weeks than the respective fresh products
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Microencapsulation of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 by spray drying in goat's milk
Small Ruminant Research, 2015Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:A mixture of probiotic Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel potential probiotic Propionibacterium jensenii 702 was resuspended in reconstituted (20% w/v) goat's milk, spray dried in a mini spray dryer (inlet temperature=195°C and outlet temperature=85°C) and the spray dried powder was stored in air tight glass jars at 4°C and 30°C for 24 weeks. Powder quality and probiotic viability after spray drying and subsequent storage were measured. Spray drying probiotics in reconstituted goat's milk resulted in a significant reduction in the viability of all three probiotics. However, all three probiotics were able to maintain satisfactory viability levels (10⁶-10⁸cfu/g) after spray drying. While storage temperature did not appear to have a significant effect on moisture content, the viability of all three strains declined dramatically when stored at 30°C but lactobacilli and propionibacteria remained virtually unaffected under storage at 4°C, satisfying recommendations regarding the level of viable cells in probiotic foods
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Effect of dairy probiotic combinations on in vitro gastrointestinal tolerance, intestinal epithelial cell adhesion and cytokine secretion
Journal of Functional Foods, 2014Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Gastrointestinal tolerance, adhesion to intestinal epithelium and immunomodulation are critical factors in maintaining probiotic efficacy. Seven different types of fermented milk were made from goat's milk using various culture compositions of three probiotics: Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 and in vitro gastrointestinal tolerance, adhesion ability and stimulation of cytokine production by probiotics were evaluated. All probiotics and combinations demonstrated significantly lower viability after exposure to simulated gastric (pH 2.0) and intestinal (with 0.3% bile, pH 8.0) fluids (p
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Probiotic viability and physico-chemical and sensory properties of plain and stirred fruit yogurts made from goat's milk.
Food chemistry, 2012Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Abstract Probiotic plain and stirred fruit yogurts were made from goat’s milk using bacterial cultures comprising, Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702. The products were stored at 4 °C for 4 weeks, during which time the viability of the yogurt starter culture and probiotic bacteria was analysed weekly. P. jensenii 702 demonstrated the highest viability (108cfu/g) in all types of yogurt throughout the storage period, while the viability of the bifidobacteria (∼107 cfu/g) also remained above the minimum therapeutic level. The viability of L. acidophilus LA-5 fell below 106 cfu/g in yogurts, however, the addition of fruit juice appeared to support the viability of lactobacilli, with higher microorganism numbers observed in fruit yogurts than in plain yogurt throughout the shelf life. Addition of fruit juice significantly increased the syneresis, and decreased viscosity and water holding capacity of yogurts (p
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In vitro analysis of gastrointestinal tolerance and intestinal cell adhesion of probiotics in goat's milk ice cream and yogurt
Food Research International, 2012Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Abstract Effect of carrier food type on in vitro gastrointestinal survival and adhesion ability of probiotic Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 were evaluated using goat's milk ice cream, plain and fruit yogurts. Carrier food matrix had a significant influence on the in vitro gastrointestinal tolerance of all three probiotics when exposed to both highly acidic conditions (pH 2.0) and 0.3% bile. Exposure to conditions of lower pH (pH 2.0) resulted in a significant reduction in probiotic viability during simulated gastric transit tolerance compared to pH levels of 3.0 and 4.0. However, ice cream was generally found to improve the acid and bile tolerance of the probiotics compared to plain and stirred fruit yogurts. In a similar manner, the in vitro adhesion ability of probiotics was found to be influenced by the carrier food matrix, with fruit yogurt providing the most favorable outcomes, although in all cases a substantial number of viable bacteria (105–106 cfu/g) were able to attach to the Caco-2 cells.
Chaminda Senaka Ranadheera - One of the best experts on this subject based on the ideXlab platform.
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In vitro investigation of the effect of dairy propionibacteria on rumen pH, lactic acid and volatile fatty acids
Journal of Integrative Agriculture, 2017Co-Authors: Jianbiao Luo, Chaminda Senaka Ranadheera, Stuart King, Craig Evans, Surinder BainesAbstract:Abstract Ruminal acidosis is a prevalent disorder in ruminants such as dairy cows and feedlot beef cattle, caused primarily by the inclusion of a high percentage of readily fermentable concentrates in the diet. The disorder presents as an accumulation of lactic acid, a decrease of pH in the rumen and a subsequent imbalance of the rumen fermentation process with detrimental impacts on the animal's health and productivity. Dairy propionibacteria, a group of bacteria characterised by utilization of lactic acid as the favoured carbon source, with propionic acid produced as a by-product, were evaluated in this study as potential direct-fed microbials for use in controlling ruminal acidosis. Acidosis was simulated by introduction of high concentrations of lactic acid into rumen fluid samples and a multi-strain in vitro analysis was conducted, whereby changes in pH and lactic acid metabolism were compared in identical acidified rumen samples, following inoculation with various propionibacteria. This was followed by a study to evaluate the effect of bacterial inoculation dosage on acid metabolism. The results indicated that lactic acid levels in the rumen fluid were significantly reduced, and propionic acid and acetic acid concentrations both significantly increased, following addition of propionibacteria. Significant ‘between strains’ differences were observed, with Propionibacterium acidopropionici 341, Propionibacterium freudenreichii CSCC 2207, Propionibacterium jensenii NCFB 572 and P. jensenii 702 each producing more rapid reduction of lactic acid concentration than P. freudenreichii CSCC 2206, P. acidopropionici ATCC 25562 and Propionibacterium thoenii ATCC 4874. Furthermore, the efficacy of this application was dosage related, with the rates of reduction in lactic acid levels and production of propionic acid, both significantly greater for the higher (10 10 cfu mL −1 ) compared with lower (10 5 cfu mL −1 ) dosage inoculation. The results confirmed that the introduction of propionibacteria could promote more rapid reduction of lactic acid levels than would occur without their addition, demonstrating their potential in controlling ruminal acidosis.
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Co-culturing of probiotics influences the microbial and physico-chemical properties but not sensory quality of fermented dairy drink made from goats’ milk
Small Ruminant Research, 2016Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Seven different types of fermented drinking milk were made from goats’ milk using various culture compositions of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel putative probiotic Propionibacterium jensenii 702. Probiotic viability, physico-chemical and sensory properties of fermented milk were measured during 3 weeks of storage at 4 °C. All three probiotics were able to maintain high viability (>107 cfu mL−1) during fermentation and subsequent storage regardless of the culture composition in goats’ milk without major antagonistic effects. Acidity of all fermented milk samples increased during storage, however there were no significant differences among preparations for organoleptic properties. Generally, lower sensory acceptability was recorded for the samples stored for 3 weeks than the respective fresh products
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Microencapsulation of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 by spray drying in goat's milk
Small Ruminant Research, 2015Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:A mixture of probiotic Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel potential probiotic Propionibacterium jensenii 702 was resuspended in reconstituted (20% w/v) goat's milk, spray dried in a mini spray dryer (inlet temperature=195°C and outlet temperature=85°C) and the spray dried powder was stored in air tight glass jars at 4°C and 30°C for 24 weeks. Powder quality and probiotic viability after spray drying and subsequent storage were measured. Spray drying probiotics in reconstituted goat's milk resulted in a significant reduction in the viability of all three probiotics. However, all three probiotics were able to maintain satisfactory viability levels (10⁶-10⁸cfu/g) after spray drying. While storage temperature did not appear to have a significant effect on moisture content, the viability of all three strains declined dramatically when stored at 30°C but lactobacilli and propionibacteria remained virtually unaffected under storage at 4°C, satisfying recommendations regarding the level of viable cells in probiotic foods
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Effect of dairy probiotic combinations on in vitro gastrointestinal tolerance, intestinal epithelial cell adhesion and cytokine secretion
Journal of Functional Foods, 2014Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Gastrointestinal tolerance, adhesion to intestinal epithelium and immunomodulation are critical factors in maintaining probiotic efficacy. Seven different types of fermented milk were made from goat's milk using various culture compositions of three probiotics: Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 and in vitro gastrointestinal tolerance, adhesion ability and stimulation of cytokine production by probiotics were evaluated. All probiotics and combinations demonstrated significantly lower viability after exposure to simulated gastric (pH 2.0) and intestinal (with 0.3% bile, pH 8.0) fluids (p
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Probiotic viability and physico-chemical and sensory properties of plain and stirred fruit yogurts made from goat's milk.
Food chemistry, 2012Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Abstract Probiotic plain and stirred fruit yogurts were made from goat’s milk using bacterial cultures comprising, Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702. The products were stored at 4 °C for 4 weeks, during which time the viability of the yogurt starter culture and probiotic bacteria was analysed weekly. P. jensenii 702 demonstrated the highest viability (108cfu/g) in all types of yogurt throughout the storage period, while the viability of the bifidobacteria (∼107 cfu/g) also remained above the minimum therapeutic level. The viability of L. acidophilus LA-5 fell below 106 cfu/g in yogurts, however, the addition of fruit juice appeared to support the viability of lactobacilli, with higher microorganism numbers observed in fruit yogurts than in plain yogurt throughout the shelf life. Addition of fruit juice significantly increased the syneresis, and decreased viscosity and water holding capacity of yogurts (p
Helge Holo - One of the best experts on this subject based on the ideXlab platform.
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Using strains of Propionibacteria to mitigate methane emissions in vitro
Acta Agriculturae Scandinavica Section A - Animal Science, 2012Co-Authors: A. Y. Alazzeh, Helge Holo, Odd Magne Harstad, Halima Sultana, Karen A. Beauchemin, Yanan Wang, Tim A. McallisterAbstract:Abstract Sixteen strains of propionibacteria were inoculated into in vitro ruminal incubations to evaluate their potential to reduce methane (CH4) production from concentrate and forage diets. Propionibacterium freudenreichii T114, Propionibacterium thoenii T159, and Propionibacterium thoenii ATCC 4874 lowered (p < 0.05) CH4 production from both substrates compared to control. Compared to control, Propionibacterium jensenii T1, Propionibacterium freudenreichii T31, and Propionibacterium freudenreichii T54 lowered (p < 0.05) CH4 production only with corn. Propionibacterium propionicus T83 caused higher (p < 0.05) propionate percentage and lower (p < 0.05) acetate:propionate than the control with corn; however, this did not result in a decline in CH4 production. Results demonstrate that some strains of propionibacteria have the potential to lower CH4 production from mixed ruminal cultures and that this reduction is not always associated with an increase in propionate production.
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Propionibacterium jensenii produces the polyene pigment granadaene and has hemolytic properties similar to those of Streptococcus agalactiae.
Applied and environmental microbiology, 2007Co-Authors: Christin Vanberg, Thor Langsrud, Ingolf F. Nes, Bjart Frode Lutnaes, Helge HoloAbstract:The red polyene pigment granadaene was purified and identified from Propionibacterium jensenii. Granadaene has previously been identified only in Streptococcus agalactiae, where the pigment correlates with the hemolytic activity of the bacterium. A connection between hemolytic activity and the production of the red pigment has also been observed in P. jensenii, as nonpigmented strains are nonhemolytic. The pigment and hemolytic activity from S. agalactiae can be extracted from the bacterium with a starch extraction solution, and this solution also extracts the pigment and hemolytic activity from P. jensenii. A partial purification of the hemolytic activity was achieved, but the requirement for starch to preserve its activity made the purification unsuccessful. Partially purified hemolytic fractions were pigmented, and the color intensity of the fractions coincided with the hemolytic titer. The pigment was produced in a soluble form when associated with starch, and the UV-visual spectrum of the extract gave absorption peaks of 463 nm, 492 nm, and 524 nm. The pigment could also be extracted from the cells by a low-salt buffer, but it was then aggregated. The purification of the pigment from P. jensenii was performed, and mass spectrometry and nuclear magnetic resonance analysis revealed that P. jensenii indeed produces granadaene as seen in S. agalactiae.
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Prevalence of the Genes Encoding Propionicin T1 and Protease-Activated Antimicrobial Peptide and Their Expression in Classical Propionibacteria
Applied and environmental microbiology, 2004Co-Authors: Therese Faye, Dag Anders Brede, Thor Langsrud, Ingolf F. Nes, Helge HoloAbstract:The purpose of this study was to investigate the frequency of production of the bacteriocin propionicin T1 and the protease-activated antimicrobial peptide (PAMP) and their corresponding genes in 64 isolates of classical propionibacteria. This study revealed that these genes are widespread in Propionibacterium jensenii and Propionibacterium thoenii but absent from the remaining species of classical propionibacteria that were studied. The pro-PAMP-encoding gene (pamA) was found in 63% of the P. jensenii strains and 61% of the P. thoenii strains, and all of these strains displayed PAMP activity. The propionicin T1-encoding gene (pctA) was present in 89% of the P. thoenii strains and 54% of the P. jensenii strains. All P. thoenii strains containing the pctA gene exhibited antimicrobial activity corresponding to propionicin T1 activity, whereas only 38% of the pctA-containing P. jensenii strains displayed this activity. Sequencing of the pctA genes revealed the existence of two allelic variants that differed in a single nucleotide in six strains of P. jensenii; in these strains the glycine at position 55 of propionicin T1 was replaced by an aspartate residue (A variant). No strains harboring the A variant showed any antimicrobial activity against propionicin T1-sensitive bacteria. An open reading frame (orf2) located immediately downstream from the pctA gene was absent in three strains containing the G variant of propionicin T1. Two of these strains showed low antimicrobial activity, while the third strain showed no antimicrobial activity at all. The protein encoded by orf2 showed strong homology to ABC transporters, and it has been proposed previously that this protein is involved in the producer immunity against propionicin T1. The limited antimicrobial activity exhibited by the strains lacking orf2 further suggests that this putative ABC transporter plays an important role in propionicin T1 activity.
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An Antimicrobial Peptide Is Produced by Extracellular Processing of a Protein from Propionibacterium jensenii
Journal of Bacteriology, 2002Co-Authors: Therese Faye, Dag Anders Brede, Thor Langsrud, Helge HoloAbstract:Antimicrobial peptides are produced by all kinds of organisms, from bacteria to mammals. In higher organisms these compounds are produced as an innate host defense mechanism to protect against pathogenic attack, whereas microorganisms presumably use these compounds as weapons in the competition for limited resources. A large number of antimicrobial peptides have been isolated from amphibians (35), fish (2, 22), insects (32), mammals (13), plants (1), and different microorganisms (12). Antimicrobial proteins and peptides from bacteria include toxins like diphtheria and cholera toxins (24, 25), bacteriolytic enzymes like lysostaphin (30) and hemolysins (8), and bacteriocins and bacteriocin-like peptides (10, 12). Numerous bacteriocins have been characterized from gram-positive bacteria, and some of them show a relatively broad spectrum of inhibition. Antimicrobial peptides produced by food-grade organisms such as lactic acid bacteria and propionibacteria have received special interest due to their potential applications in food preservation (33). The classical propionibacteria have a long history of use in dairy fermentations, in particular the production of Swiss-type cheeses. A few antimicrobial peptides from these bacteria have been described so far (7, 9, 14, 15, 17, 21, 29), and only two bacteriocins have been characterized at the molecular level (7, 17). Bacteria use a number of different mechanisms to regulate and produce active peptides and proteins. Most conventional bacteriocins are produced as precursor peptides, which are modified posttranslationally inside the cell or at the cell exterior during export to generate their biologically active forms (12). However, it has been shown that antimicrobial peptides from both bacteria (27, 28) and higher organisms (23, 31) can be produced from the degradation of larger proteins. In this work we describe a novel antimicrobial peptide isolated from Propionibacterium jensenii LMG 3032. This compound is secreted from the cell as an inactive proprotein which is proteolytically activated by proteases in the environment. The mature peptide has several features in common with well-known antimicrobial peptides like class II bacteriocins and antimicrobial cationic peptides from higher organisms. This is to our knowledge the first bacteriocin-like peptide formed from an inactive extracellular protein by an external protease.
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Biochemical and genetic characterization of propionicin T1, a new bacteriocin from Propionibacterium thoenii.
Applied and environmental microbiology, 2000Co-Authors: Therese Faye, Thor Langsrud, Ingolf F. Nes, Helge HoloAbstract:A collection of propionibacteria was screened for bacteriocin production. A new bacteriocin named propionicin T1 was isolated from two strains of Propionibacterium thoenii. This bacteriocin shows no sequence similarity to other bacteriocins. Propionicin T1 was active against all strains of Propionibacterium acidipropionici, Propionibacterium thoenii, and Propionibacterium jensenii tested and also against Lactobacillus sake NCDO 2714 but showed no activity against Propionibacterium freudenreichii. The bacteriocin was purified, and the N-terminal part of the peptide was determined with amino acid sequencing. The corresponding gene pctA was sequenced, and this revealed that propionicin T1 is produced as a prebacteriocin of 96 amino acids with a typical sec leader, which is processed to give a mature bacteriocin of 65 amino acids. An open reading frame encoding a protein of 424 amino acids was found 68 nucleotides downstream the stop codon of pctA. The N-terminal part of this putative protein shows strong similarity with the ATP-binding cassette of prokaryotic and eukaryotic ABC transporters, and this protein may be involved in self-protection against propionicin T1. Propionicin T1 is the first bacteriocin from propionibacteria that has been isolated and further characterized at the molecular level.
Craig Evans - One of the best experts on this subject based on the ideXlab platform.
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In vitro investigation of the effect of dairy propionibacteria on rumen pH, lactic acid and volatile fatty acids
Journal of Integrative Agriculture, 2017Co-Authors: Jianbiao Luo, Chaminda Senaka Ranadheera, Stuart King, Craig Evans, Surinder BainesAbstract:Abstract Ruminal acidosis is a prevalent disorder in ruminants such as dairy cows and feedlot beef cattle, caused primarily by the inclusion of a high percentage of readily fermentable concentrates in the diet. The disorder presents as an accumulation of lactic acid, a decrease of pH in the rumen and a subsequent imbalance of the rumen fermentation process with detrimental impacts on the animal's health and productivity. Dairy propionibacteria, a group of bacteria characterised by utilization of lactic acid as the favoured carbon source, with propionic acid produced as a by-product, were evaluated in this study as potential direct-fed microbials for use in controlling ruminal acidosis. Acidosis was simulated by introduction of high concentrations of lactic acid into rumen fluid samples and a multi-strain in vitro analysis was conducted, whereby changes in pH and lactic acid metabolism were compared in identical acidified rumen samples, following inoculation with various propionibacteria. This was followed by a study to evaluate the effect of bacterial inoculation dosage on acid metabolism. The results indicated that lactic acid levels in the rumen fluid were significantly reduced, and propionic acid and acetic acid concentrations both significantly increased, following addition of propionibacteria. Significant ‘between strains’ differences were observed, with Propionibacterium acidopropionici 341, Propionibacterium freudenreichii CSCC 2207, Propionibacterium jensenii NCFB 572 and P. jensenii 702 each producing more rapid reduction of lactic acid concentration than P. freudenreichii CSCC 2206, P. acidopropionici ATCC 25562 and Propionibacterium thoenii ATCC 4874. Furthermore, the efficacy of this application was dosage related, with the rates of reduction in lactic acid levels and production of propionic acid, both significantly greater for the higher (10 10 cfu mL −1 ) compared with lower (10 5 cfu mL −1 ) dosage inoculation. The results confirmed that the introduction of propionibacteria could promote more rapid reduction of lactic acid levels than would occur without their addition, demonstrating their potential in controlling ruminal acidosis.
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Co-culturing of probiotics influences the microbial and physico-chemical properties but not sensory quality of fermented dairy drink made from goats’ milk
Small Ruminant Research, 2016Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Seven different types of fermented drinking milk were made from goats’ milk using various culture compositions of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel putative probiotic Propionibacterium jensenii 702. Probiotic viability, physico-chemical and sensory properties of fermented milk were measured during 3 weeks of storage at 4 °C. All three probiotics were able to maintain high viability (>107 cfu mL−1) during fermentation and subsequent storage regardless of the culture composition in goats’ milk without major antagonistic effects. Acidity of all fermented milk samples increased during storage, however there were no significant differences among preparations for organoleptic properties. Generally, lower sensory acceptability was recorded for the samples stored for 3 weeks than the respective fresh products
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Microencapsulation of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 by spray drying in goat's milk
Small Ruminant Research, 2015Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:A mixture of probiotic Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and novel potential probiotic Propionibacterium jensenii 702 was resuspended in reconstituted (20% w/v) goat's milk, spray dried in a mini spray dryer (inlet temperature=195°C and outlet temperature=85°C) and the spray dried powder was stored in air tight glass jars at 4°C and 30°C for 24 weeks. Powder quality and probiotic viability after spray drying and subsequent storage were measured. Spray drying probiotics in reconstituted goat's milk resulted in a significant reduction in the viability of all three probiotics. However, all three probiotics were able to maintain satisfactory viability levels (10⁶-10⁸cfu/g) after spray drying. While storage temperature did not appear to have a significant effect on moisture content, the viability of all three strains declined dramatically when stored at 30°C but lactobacilli and propionibacteria remained virtually unaffected under storage at 4°C, satisfying recommendations regarding the level of viable cells in probiotic foods
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Effect of dairy probiotic combinations on in vitro gastrointestinal tolerance, intestinal epithelial cell adhesion and cytokine secretion
Journal of Functional Foods, 2014Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Gastrointestinal tolerance, adhesion to intestinal epithelium and immunomodulation are critical factors in maintaining probiotic efficacy. Seven different types of fermented milk were made from goat's milk using various culture compositions of three probiotics: Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702 and in vitro gastrointestinal tolerance, adhesion ability and stimulation of cytokine production by probiotics were evaluated. All probiotics and combinations demonstrated significantly lower viability after exposure to simulated gastric (pH 2.0) and intestinal (with 0.3% bile, pH 8.0) fluids (p
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Probiotic viability and physico-chemical and sensory properties of plain and stirred fruit yogurts made from goat's milk.
Food chemistry, 2012Co-Authors: Chaminda Senaka Ranadheera, Craig Evans, Michelle C. Adams, Surinder BainesAbstract:Abstract Probiotic plain and stirred fruit yogurts were made from goat’s milk using bacterial cultures comprising, Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Propionibacterium jensenii 702. The products were stored at 4 °C for 4 weeks, during which time the viability of the yogurt starter culture and probiotic bacteria was analysed weekly. P. jensenii 702 demonstrated the highest viability (108cfu/g) in all types of yogurt throughout the storage period, while the viability of the bifidobacteria (∼107 cfu/g) also remained above the minimum therapeutic level. The viability of L. acidophilus LA-5 fell below 106 cfu/g in yogurts, however, the addition of fruit juice appeared to support the viability of lactobacilli, with higher microorganism numbers observed in fruit yogurts than in plain yogurt throughout the shelf life. Addition of fruit juice significantly increased the syneresis, and decreased viscosity and water holding capacity of yogurts (p
