RESUMEN

Tuberculosis is a highly contagious disease caused by Mycobacterium tuberculosis. It affects about 10 million people each year and is still one of the leading causes of death worldwide. About 2 to 3 billion people (equivalent to 1 in 3 people in the world) are infected with latent tuberculosis. Moreover, as the number of multidrug-resistant, extensively drug-resistant, and totally drug-resistant strains of M. tuberculosis continues to increase, there is an urgent need to develop new anti-tuberculosis drugs that are different from existing drugs to combat antibiotic-resistant M. tuberculosis. Against this background, we aimed to develop new anti-tuberculosis drugs using probiotics. Here, we report the anti-tuberculosis effect of Pediococcus acidilactici PMC202 isolated from young radish kimchi, a traditional Korean fermented food. Under coculture conditions, PMC202 inhibited the growth of M. tuberculosis. In addition, PMC202 inhibited the growth of drug-sensitive and -resistant M. tuberculosis- infected macrophages at a concentration that did not show cytotoxicity and showed a synergistic effect with isoniazid. In a 2-week, repeated oral administration toxicity study using mice, PMC202 did not cause weight change or specific clinical symptoms. Furthermore, the results of 16S rRNA-based metagenomics analysis confirmed that dysbiosis was not induced in bronchoalveolar lavage fluid after oral administration of PMC202. The anti-tuberculosis effect of PMC202 was found to be related to the reduction of nitric oxide. Our findings indicate that PMC202 could be used as an anti-tuberculosis drug candidate with the potential to replace current chemicalbased drugs. However, more extensive toxicity, mechanism of action, and animal efficacy studies with clinical trials are needed.

Asunto(s)

Alimentos Fermentados/microbiología , Mycobacterium tuberculosis/efectos de los fármacos , Pediococcus acidilactici/fisiología , Raphanus/microbiología , Animales , Antituberculosos/administración & dosificación , Antituberculosos/farmacología , Medios de Cultivo Condicionados/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/microbiología , Ratones , Microbiota , Mycobacterium tuberculosis/crecimiento & desarrollo , Óxido Nítrico/metabolismo , Pediococcus acidilactici/aislamiento & purificación , Probióticos/administración & dosificación , Probióticos/farmacología , Células RAW 264.7 , ARN Ribosómico 16S/genética

RESUMEN

Listeria monocytogenes is an important food-borne pathogen and a serious concern to food industries. Bacteriocins are antimicrobial peptides produced naturally by a wide range of bacteria mostly belonging to the group of lactic acid bacteria (LAB), which also comprises many strains used as starter cultures or probiotic supplements. Consequently, multifunctional strains that produce bacteriocins are an attractive approach to combine a green-label approach for food preservation with an important probiotic trait. Here, a collection of bacterial isolates from raw cow's milk was typed by 16S rRNA gene sequencing and MALDI-Biotyping and supernatants were screened for the production of antimicrobial compounds. Screening was performed with live Listeria monocytogenes biosensors using a growth-dependent assay and pHluorin, a pH-dependent protein reporting membrane damage. Purification by cation exchange chromatography and further investigation of the active compounds in supernatants of two isolates belonging to the species Pediococcus acidilactici and Lactococcus garvieae suggest that their antimicrobial activity is related to heat-stable proteins/peptides that presumably belong to the class IIa bacteriocins. In conclusion, we present a pipeline of methods for high-throughput screening of strain libraries for potential starter cultures and probiotics producing antimicrobial compounds and their identification and analysis.

Asunto(s)

Antibacterianos/farmacología , Bacteriocinas/farmacología , Descubrimiento de Drogas/métodos , Listeria monocytogenes/efectos de los fármacos , Probióticos , Animales , Antibacterianos/biosíntesis , Bacteriocinas/biosíntesis , Lactococcus/aislamiento & purificación , Lactococcus/metabolismo , Microbiota , Leche/microbiología , Pediococcus acidilactici/aislamiento & purificación , Pediococcus acidilactici/metabolismo

RESUMEN

Our aim was to isolate, identify and characterize probiotic bacteria as vitamin producers in particular B2 and B9. 150 human fecal samples were collected and used for isolation of vitamin producers-probiotics. 49 isolates were chosen for screening their genome by PCR for the presence of riboflavin and folic acid genes. As a result, three isolates were selected and their production of the B2 and B9 were confirmed by HPLC. The three isolates were identified on species level by sequencing their 16S rRNA gene which showed 100% identical to strains of Pediococcus acidilactici. Thus, they were named as P. acidilactici WNYM01, P. acidilactici WNYM02, P. acidilactici WNYM03 and submitted to the Genbank database with accession numbers. They met the probiotic criteria by expressing 90-95% survival rate at pH (2.0-9.0) and bile salt up to 2% for 3 h in addition to their antimicrobial activity against gram positive and negative microorganisms. They also showed no hemolytic activity and common pattern for antibiotic susceptibility. Our three strains were tested individually or in mixture in vivo on rat colitis model compared to ulcerative group. The strains were administrated orally to rats in daily dose containing CFU 109 for 14 days then followed by induction of colitis using acetic acid then the oral administration was continued for more four days. The histology results, the anti-inflammatory and anti-oxidative stress biomarkers showed the protective role of the strains compared to the ulcerative group. As a conclusion, we introduce novel three probiotic candidates for pharmaceutical preparations and health applications.

Asunto(s)

Colitis/terapia , Ácido Fólico/metabolismo , Microbioma Gastrointestinal , Pediococcus acidilactici/fisiología , Probióticos/administración & dosificación , Riboflavina/metabolismo , Ácido Acético/toxicidad , Administración Oral , Animales , Antibacterianos/farmacología , Ácidos y Sales Biliares/farmacología , Colitis/inducido químicamente , Colon/patología , Modelos Animales de Enfermedad , Heces/microbiología , Ácido Fólico/análisis , Humanos , Concentración de Iones de Hidrógeno , Masculino , Pediococcus acidilactici/efectos de los fármacos , Pediococcus acidilactici/genética , Pediococcus acidilactici/aislamiento & purificación , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/metabolismo , Ratas , Ratas Wistar , Riboflavina/análisis

RESUMEN

In this study, the chemical structure and bioactive properties of the EPS of Pediococcus acidilactici MT41-11 isolated from camel milk were investigated. Two polysaccharide fractions (EPS-1, EPS-2) with molecular weights about 69.0 kDa were obtained, which were purified using DEAE-Sepharose and Sephadex G-100 chromatography. Based on monosaccharide composition, FT-IR, and 1D, 2D NMR spectra, concluded that EPS-1 had a backbone composed of →2)-α-d-Manp-(1→, →3)-α-d-Manp-(1→ and with branches containing α-d-Manp-(1→, EPS-2 had a backbone composed of →6)-ß-d-Glcp-(1→, and with branches containing →2)-α-l-Fucp-(1→, →3)-α-d-Glcp-(1→, →2)-α-d-Glcp-(1→, ß-d-Glcp-(1→, and α-d-Glcp-(1→. Remarkably, in vitro assays showed that EPS possessed multiple bioactive properties, including stimulating Lactobacillus growth and a high DPPH free radical scavenging activity. Also, it has a good ability to anti-biofilms. Overall, the analysis of all data showed EPS from P. acidilactici MT41-11 can be used as anti-oxidant, anti-biofilm agent, and also as a potential candidate prebiotic for health food or medicine industry.

Asunto(s)

Lactobacillus/crecimiento & desarrollo , Leche/microbiología , Pediococcus acidilactici/aislamiento & purificación , Polisacáridos Bacterianos/química , Animales , Antioxidantes/química , Antioxidantes/farmacología , Camelus , Secuencia de Carbohidratos , Lactobacillus/efectos de los fármacos , Peso Molecular , Pediococcus acidilactici/química , Polisacáridos Bacterianos/farmacología

RESUMEN

Salmonella, Shiga toxin-producing Escherichia coli (STEC), and Listeria monocytogenes have been isolated from low water activity foods (LWAF), where they may survive for extended periods. The ready-to-eat nature of many LWAF, such as dried fruits and nuts, warrants effective post-harvest thermal treatment for the reduction of pathogens such as low-temperature, saturated steam, also known as vacuum-assisted steam pasteurization. The objective of this study was to determine reductions of Salmonella, STEC, L. monocytogenes, and a possible surrogate (Pediococcus acidilactici) on dried apricot halves, whole macadamia nuts, and raisins after treatment with vacuum-assisted steam at three temperatures (62 °C, 72 °C, or 82 °C) and multiple time intervals. Bacterial inactivation was variable between commodities, with higher temperatures and longer times necessary to achieve comparable reductions of pathogens on apricot halves and macadamia nuts compared to raisins. Reductions of the tested pathogens were comparable; therefore, one species was not more resistant than the others. Pathogens were reduced by 5-log CFU/g on apricot halves after 20 min at 72 °C and after 5 min at 82 °C. Longer treatment times were necessary to achieve reductions of each pathogen on macadamia nuts. Pathogens were reduced by nearly 5 log CFU/g on macadamia nuts after 38 min at 72 °C (4.6-6.5 log CFU/g) and after 12 min at 82 °C (4.9-5.7 log CFU/g). Reductions of pathogens on raisins were achieved at lower temperatures than necessary for the other foods. A 5-log reduction for each of the pathogens (CFU/g) on raisins occurred after 20 min at 62 °C and after 5 min at 72 °C. Overall, the reductions of the pathogens exceeded those of P. acidilactici on both the dried fruits and macadamia nuts. Statistically significant differences, indicating greater confidence as a conservative surrogate, were observed at lower treatment temperatures. Inactivation kinetics were modeled for each pathogen on each food type and temperature. Bacterial survival was best described by the Weibull model for raisins and macadamia nuts, while the Gompertz model best described reductions on apricot halves according to Akaike information criterion (AIC) and root-mean-square error (RMSE) evaluations. Water activity and moisture content were increased due to the treatments, which could be addressed through implementation of drying steps. Thermal inactivation kinetic models and 5-log reduction parameters can help food processors design and evaluate similar vacuum-assisted steam interventions to comply with FSMA regulations and preventive control plans. However, results or model predictions should not be extrapolated to assume the safety of other types of foods.

Asunto(s)

Bacterias/aislamiento & purificación , Macadamia/microbiología , Pasteurización/métodos , Prunus armeniaca/microbiología , Vitis/microbiología , Bacterias/crecimiento & desarrollo , Microbiología de Alimentos , Calor , Listeria monocytogenes/aislamiento & purificación , Nueces , Pediococcus acidilactici/aislamiento & purificación , Salmonella/aislamiento & purificación , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Vapor , Vacio

RESUMEN

Overproduction and accumulation of melanin in the skin will darken the skin and cause skin disorders. So far, components that can inhibit tyrosinase, a melanin synthase of melanocytes, have been developed and used as ingredients of cosmetics or pharmaceutical products. However, most of existing substances can only inhibit the biosynthesis of melanin while melanin that is already synthesized and deposited is not directly decomposed. Thus, their effects in decreasing melanin concentration in the skin are weak. To overcome the limitation of existing therapeutic agents, we started to develop a substance that could directly biodegrade melanin. We screened traditional fermented food microorganisms for their abilities to direct biodegrade melanin. As a result, we found that a kimchi-derived Pediococcus acidilactici PMC48 had a direct melanin-degrading effect. This PMC48 strain is a new strain, different from P. acidilactici strains reported so far. It not only directly degrades melanin, but also has tyrosinase-inhibiting effect. It has a direct melanindecomposition effect. It exceeds existing melanin synthesis-inhibiting technology. It is expected to be of high value as a raw material for melanin degradation drugs and cosmetics.

Asunto(s)

Alimentos Fermentados/microbiología , Melaninas/biosíntesis , Pediococcus acidilactici/aislamiento & purificación , Pediococcus acidilactici/metabolismo , Perilla/microbiología , Hojas de la Planta/microbiología , Supervivencia Celular/efectos de los fármacos , Melanocitos/efectos de los fármacos , Monofenol Monooxigenasa , Pediococcus acidilactici/genética , Filogenia , ARN Ribosómico 16S , República de Corea

RESUMEN

With regards to the frequently reported findings of spoilage bacteria and pathogens in various foods there is a need to explore new ways to control hazards in food production and to improve consumer safety. Fermented sausages from traditional and industrial production in Germany were screened for lactic acid bacteria with antibacterial effects towards important foodborne pathogens (Escherichia coli DSM 1103, Listeria innocua DSM 20649, Listeria monocytogenes DSM 19094, Pseudomonas aeruginosa DSM 939, Staphylococcus aureus DSM 799 and Salmonella Typhimurium DSM 19587). The obtained isolates and their cell-free supernatants were tested for their antibacterial activity by agar well diffusion assay. Isolates with an inhibitory effect were examined for the underlying antibacterial mechanism. Among the 169 collected isolates, 12.4% showed antibacterial effects only against Listeria innocua DSM 20649 and Listeria monocytogenes DSM 19094. In 6.5% of the isolates, bacteriocins were responsible for the effect. On the remaining test strains, the lactic bacteria isolates exerted no antibacterial effect. Two isolates were selected based on their antibacterial potential against Listeria spp. and the thermostability of the deriving cell free supernatants, traditional product: Pediococcus pentosaceus LMQS 331.3, industrial product: Pediococcus acidilactici LMQS 154.1, were investigated further and confirmed for the presence of bacteriocin structural genes by real-time PCR. Enriched crude bacteriocin preparations were obtained by ammonium sulfate precipitation and were found to remain stable under different pH milieus and to be active towards an extended set of Listeria spp. strains. Fermented meat products from German production are a promising source for bacteriocin-producing lactic acid bacteria. Two bacteriocin-producing isolates were identified which have the potential to contribute to product and consumer safety.

Asunto(s)

Antibacterianos/metabolismo , Alimentos Fermentados/microbiología , Pediocinas/metabolismo , Pediococcus acidilactici/aislamiento & purificación , Pediococcus pentosaceus/aislamiento & purificación , Fermentación , Industria de Alimentos , Microbiología de Alimentos , Inocuidad de los Alimentos , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Alemania , Productos de la Carne/microbiología , Pruebas de Sensibilidad Microbiana , Pediococcus acidilactici/metabolismo , Pediococcus pentosaceus/metabolismo

RESUMEN

Lipolysis occurs during ripening of dairy products as a result of esterase or lipase activity. Lactic acid bacteria (LAB) are considered to be weakly lipolytic bacteria compared with other species. In cheeses with extended ripening periods, lipolytic LAB may have several advantages. Pediococcus acidilactici is a LAB frequently found in fermented dairy products, but no previous reports exist on their production of esterases or lipases. Our interest in the relationship of LAB and enzymatic characterization is due to the multiple reports of the benefits of LAB in the gut microbiome, particularly at the intestinal membrane. Pediococci have been characterized as probiotic and especially active in membrane interactions. The aim of this project was to purify, characterize, and identify the phosphoesterase produced by P. acidilactici originally isolated from Gouda cheese and determine its phospholipid (PL) hydrolysis profile, with a focus on increased absorption of these compounds in the human gut. Native zymograms were performed to identify a protein with lipolytic activity in the intracellular fraction of P. acidilactici. The enzyme was purified via size-exclusion HPLC, concentrated via ultrafiltration, and identified using sequence analysis in liquid chromatography (LC)-MS/MS. The purified fraction was subjected to biochemical characterization as a function of pH, temperature, ion concentration, hydrolysis of different substrates, and PL. A single protein with a molecular weight of 86 kDa and esterase activity was detected by zymography. Analysis of the LC-MS/MS results identified a putative metallophosphoesterase with a calculated molecular weight of 45.5 kDa, suggesting that this protein is active as a homodimer. The pure protein showed an optimal activity between pH 8.0 to 9.0. The optimal temperature for activity was 37°C, and the enzyme lost 15% of activity after incubation at 90°C for 1 h. This enzyme showed activity on short-chain fatty acids and exhibited high hydrolysis of phosphatidylinositol. It also hydrolyzed phosphatidylserine, phosphatidylcholine, and sphingomyelin. Phosphatidylethanolamine was hydrolyzed but with less efficiency. The characteristics and lipolytic actions exerted by this protein obtained from LAB hold promise for a potential strain of esterase or lipase that may exert human health benefits through increased digestibility and absorption of nutrients found in dairy products.

Asunto(s)

Queso/microbiología , Pediococcus acidilactici/enzimología , Fosfoproteínas Fosfatasas/aislamiento & purificación , Animales , Cromatografía Liquida , Humanos , Hidrólisis , Lipólisis , Peso Molecular , Pediococcus acidilactici/aislamiento & purificación , Fosfoproteínas Fosfatasas/metabolismo , Espectrometría de Masas en Tándem

RESUMEN

The nutritional challenge faced by the monogastric animals due to the chelation effects of phytic acid, fuel the research on bioprospecting of probiotics for phytase production. Pediococcus acidilactici SMVDUDB2 isolated from Kalarei, exhibited extracellular phytase activity of 5.583 U/mL after statistical optimization of fermentation conditions viz. peptone (1.27%); temperature (37 °C); pH (6.26) and maltose (1.43%). The phytase enzyme possessed optimum pH and temperature of 5.5 and 37 °C, respectively and was thermostable at 60 °C. The enzyme was purified 6.42 fold with a specific activity of 245.12 U/mg with hydrophobic interaction chromatography. The purified enzyme had Km and Vmax values of 0.385 mM and 4.965 µmol/min respectively, with sodium phytate as substrate. The strain depicted more than 80% survival rate at low pH (pH 2.0, 3.0), high bile salt concentration (0.3 and 0.5%), after gastrointestinal transit, highest hydrophobicity affinity with ethyl acetate (33.33 ± 0%), autoaggregation (77.68 ± 0.68%) as well as coaggregation (73.57 ± 0.47%) with Staphylococcus aureus (MTCC 3160). The strain exhibited antimicrobial activity against Bacillus subtilis (MTCC 121), Mycobacterium smegmatis (MTCC 994), Staphylococcus aureus (MTCC 3160), Proteus vulgaris (MTCC 426), Escherichia coli (MTCC 1652) and Lactobacillus rhamnosus (MTCC 1408). The amount of exopolysaccharide produced by the strain was 2 g/L. This strain having the capability of phytate degradation and possessing probiotic traits could find application in food and feed sectors.

Asunto(s)

6-Fitasa/metabolismo , Queso/microbiología , Pediococcus acidilactici/aislamiento & purificación , Probióticos/aislamiento & purificación , 6-Fitasa/aislamiento & purificación , Pruebas de Enzimas , Pediococcus acidilactici/enzimología , Ácido Fítico/metabolismo , Polisacáridos Bacterianos/biosíntesis , Probióticos/metabolismo

RESUMEN

Tryptophan is one of the most extensively used amino acids in livestock industry owing to its effectiveness in enhancing the growth performance of animals. Conventionally, the production of tryptophan relies heavily on genetically modified Escherichia coli but its pathogenicity is a great concern. Our recent study demonstrated that a lactic acid bacterium (LAB), Pediococcus acidilactici TP-6 that isolated from Malaysian food was a promising tryptophan producer. However, the tryptophan production must enhance further for viable industrial application. Hence, the current study evaluated the effects of medium components and optimized the medium composition for tryptophan production by P. acidilactici TP-6 statistically using Plackett-Burman Design, and Central Composite Design. The optimized medium containing molasses (14.06 g/L), meat extract (23.68 g/L), urea (5.56 g/L) and FeSO4 (0.024 g/L) significantly enhanced the tryptophan production by 150% as compared to the control de Man, Rogosa and Sharpe medium. The findings obtained in this study revealed that rapid evaluation and effective optimization of medium composition governing tryptophan production by P. acidilactici TP-6 were feasible via statistical approaches. Additionally, the current findings reveal the potential of utilizing LAB as a safer alternative tryptophan producer and provides insight for future exploitation of various amino acid productions by LAB.

Asunto(s)

Fermentación , Microbiología de Alimentos , Pediococcus acidilactici/metabolismo , Triptófano/biosíntesis , Aminoácidos/metabolismo , Análisis de Varianza , Ácido Láctico/metabolismo , Pediococcus acidilactici/aislamiento & purificación

RESUMEN

Clostridium difficile infection (CDI) has become a growing health concern, as evident from the increase in the mortality rate among elderly or hospitalized patients. Treatment of CDI is usually based on antibiotics (metronidazole and vancomycin), but it has some limitations, including cost and antibiotic resistance. Probiotics could offer an effective remedy to prevent CDI and could be an auxiliary agent in treatment CDI. Here, the anti-clostridial activity of a newly isolated probiotic strain, Pediococcus acidilactici SPM138 (SPM138) was evaluated. The cultivation of C. difficile (CD) with SPM138, inhibited the growth of CD and significantly reduced CD toxins level. The result of MTT assay showed that, incubation with 25% CD culture supernatant decreased the survival rate of HT-29 cells to less than 20%. However, the survival rate of these cells increased to 98% in the presence of the 25% CD + SPM138 supernatant. The mRNA expression of IL-6, IL-8 and PTGS2 in HT-29 cells decreased by more than 60% upon incubation with CD + SPM138 co-cultures as compared to the levels observed after treatment with CD supernatant only. The concentration of IL-8 also decreased by more than 60% upon treatment with CD + SPM138 co-culture supernatant. In a C. difficile PCR ribotype 027-infected mouse model, the concentration of CD toxin in stool samples of SPM138-fed mice was only 37% of that reported in C. difficile 027-infected group. These findings show that P. acidilactici SPM138 may be a promising probiotic in CDI.

Asunto(s)

Antibiosis , Clostridioides difficile/fisiología , Pediococcus acidilactici/fisiología , Animales , Toxinas Bacterianas/biosíntesis , Infecciones por Clostridium/genética , Infecciones por Clostridium/metabolismo , Infecciones por Clostridium/microbiología , Técnicas de Cocultivo , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Farmacorresistencia Bacteriana , Regulación de la Expresión Génica , Humanos , Ratones , Pediococcus acidilactici/efectos de los fármacos , Pediococcus acidilactici/aislamiento & purificación

RESUMEN

The aim of this research was to isolate bacteria capable of biotransforming daidzein from fresh feces from pregnant horses. A Hungate anaerobic roller tube was used for anaerobic culture. Single colonies were picked at random and incubated with daidzein. High performance liquid chromatography was used to detect whether the isolated bacteria were able to biotransform the substrate. A strain capable of reducing daidzein was selected and characterized using sequence analysis of 16S rDNA, and a phylogenetic tree was constructed. The morphological physiological and biochemical characteristics of the strain were investigated. A facultative anaerobic, Gram-positive bacterium capable of converting daidzein to dihydrodaidzein was isolated and named HXBM408 (MF992210). A BLAST search of HXBM408's 16S rDNA sequence against the GenBank database suggested that the strain has 99% similarity with Pediococcus acidilactici strain DSM (NR042057). The morphological, physiological, and biochemical characteristics of HXBM408 are very similar to those of Pediococcus. Based on these characteristics, the strain was identified as Pediococcus acidilactici. The bacterial strain HXBM408 isolated from the feces of pregnant horses was able to reduce the isoflavone daidzein to dihydrodaidzein.

Asunto(s)

Bacterias/aislamiento & purificación , Bacterias/metabolismo , Caballos/metabolismo , Caballos/microbiología , Isoflavonas/metabolismo , Pediococcus acidilactici/aislamiento & purificación , Pediococcus acidilactici/metabolismo , Animales , Bacterias/genética , Biotransformación , ADN Bacteriano/genética , ADN Ribosómico/genética , Heces/microbiología , Femenino , Pediococcus acidilactici/genética , Filogenia , Fitoestrógenos/metabolismo , Embarazo , ARN Ribosómico 16S/genética , Glycine max/química

RESUMEN

Aerobic plate counts are the standard enumeration method for probiotic-containing products. This counting method is limited by the ability of many cells to enter a viable but non-culturable (VBNC) state upon exposure to stressful conditions like dehydration and heating commonly used in probiotic product preparation. Alternative enumeration methods are available including flow cytometry (FC) which counts total live/dead cells by assessing cellular integrity and/or metabolic activity, and quantitative polymerase chain reaction (qPCR) in which enumeration is correlated with the quantity of a nucleic acid target. These three methods were compared for enumerating three lactic acid bacteria (LAB): Pediococcus acidilactici, Pediococcus pentosaceus, and Lactobacillus plantarum, and a Bacillus subtilis related strain in twenty samples of a mixed probiotic product ranging in age from one to 825 days post-production. Flow cytometry and qPCR enumerations were similar and much higher compared to plate counts at later storage times, suggesting that some strains in the population were entering the VBNC state and were only countable by FC and qPCR. We propose the use of FC and/or qPCR as an alternative to plate counts for more accurate enumeration of bacteria in probiotic products.

Asunto(s)

Alimentación Animal/microbiología , Bacterias/aislamiento & purificación , Carga Bacteriana/métodos , Citometría de Flujo/métodos , Probióticos/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Bacillus subtilis/aislamiento & purificación , Lactobacillus plantarum/aislamiento & purificación , Viabilidad Microbiana , Pediococcus acidilactici/aislamiento & purificación , Pediococcus pentosaceus/aislamiento & purificación

RESUMEN

AIMS: To examine the characteristics of three isolated Pediococcus acidilactici strains (LTG7, LOG9 and LH9) and evaluate their effects on silage quality, nutritive value and in vitro ruminal digestibility in a variety of forages. METHODS AND RESULTS: One commercial inoculant Lactobacillus plantarum MTD-1 (G) and three isolated lactic acid bacteria (LAB) strains were measured by morphological, physiological and biochemical tests. All the LAB strains were added to Italian ryegrass (Lolium multiflorum Lam.), tall fescue (Festuca arundinacea Schred.) and oat (Avena sativa L.) for ensiling 30 days in laboratory silos (1 l) respectively. Isolated strains could grow normally at 5-20°C, pH 3·5-7·0 and NaCl (3·0, 6·5%), and were identified as P. acidilactici by sequencing 16S rDNA. In Italian ryegrass and oat silages, all inoculants obviously (P < 0·05) increased lactic acid (LA) contents, LAB numbers and in vitro dry matter digestibility (IVDMD), and decreased pH, undesirable micro-organism numbers, butyric acid and ammonia nitrogen (NH3 -N) contents compared with the corresponding controls. LTG7, LOG9 and G silages in Italian ryegrass and oat had markedly (P < 0·05) higher LA content and IVDMD, and lower pH and NH3 -N contents than LH9 silages. In tall fescue silage, LAB inoculants had no obvious (P > 0·05) effect on fermentation quality, while markedly (P < 0·05) enhanced IVDMD. CONCLUSIONS: Based on our results, strains LTG7 and LOG9 had similar potential with the commercial inoculant G in silage making. SIGNIFICANCE AND IMPACT OF THE STUDY: Few studies involved inoculation of silage with P. acidilactici in different forage types. Analysis of effects of LAB strains with their physiological and biochemical characteristics help understand how LAB inoculants affect the digestibility.

Asunto(s)

Pediococcus acidilactici/metabolismo , Ensilaje/microbiología , Avena/microbiología , Fermentación , Festuca/microbiología , Ácido Láctico/análisis , Lactobacillales/citología , Lactobacillales/crecimiento & desarrollo , Lactobacillales/aislamiento & purificación , Lactobacillales/metabolismo , Lactobacillus plantarum/citología , Lactobacillus plantarum/crecimiento & desarrollo , Lactobacillus plantarum/metabolismo , Lolium/microbiología , Valor Nutritivo , Pediococcus acidilactici/citología , Pediococcus acidilactici/crecimiento & desarrollo , Pediococcus acidilactici/aislamiento & purificación

RESUMEN

Lactic acid bacteria were isolated from hemp (Cannabis sativa L.) flour, spontaneously fermented dough, and type I sourdough. Isolates were identified and further selected based on pro-technological, nutritional and functional properties. Lactobacillus plantarum/s5, Pediococcus acidilactici/s5, and Leuconostoc mesenteroides/s1 were used as mixed starter to produce hemp sourdough. Significant decreases of the concentration of phytic acid, condensed tannins, and total saponins were observed during fermentation. The in vitro protein digestibility increased up to 90%. Experimental wheat breads were made adding 5% to 15% (w/w) hemp sourdough to the formula, characterized, and compared to baker's yeast wheat bread manufactured without hemp sourdough. The use of hemp sourdough improved the textural features of wheat bread, without adversely affect the sensory profile. Proportionally to the fortification with hemp sourdough, protein digestibility of the breads increased, while the predicted glycemic index significantly decreased (87 vs 100%). This work demonstrated that the fermentation with selected starters improved nutritional functionality of hemp flour, allowing its large-scale use in different food applications, meeting the consumers and producers request for novel fermented baked goods with a well-balanced nutritional profile.

Asunto(s)

Pan/microbiología , Cannabis/microbiología , Fermentación/fisiología , Lactobacillus plantarum/metabolismo , Leuconostoc mesenteroides/metabolismo , Pediococcus acidilactici/metabolismo , Reactores Biológicos , Alimentos Fermentados , Harina/microbiología , Ácido Láctico/metabolismo , Lactobacillus plantarum/aislamiento & purificación , Leuconostoc mesenteroides/aislamiento & purificación , Pediococcus acidilactici/aislamiento & purificación , Ácido Fítico/análisis , Proantocianidinas/análisis , Saccharomyces cerevisiae/metabolismo , Saponinas/análisis , Triticum/microbiología , Levadura Seca

RESUMEN

The aim of the present study was isolation and molecular identification of lactic acid bacteria from King grass and their application to improve the fermentation quality of sweet Sorghum. Seventy-six strains of LAB were isolated; five strains were selected for Physiological and morphological tests and 16S rRNA sequencing. All five strains grew at different pH 3.5-8.0, different temperature 35, 40, 45, 50 °C and different NaCl concentrations 3, 6.5, 9.5%. Strains HDASK were identified Lactobacillus plantarum and SK3907, SK2A32, SK3A42 and ASKDD Pediococcus acidilactici. Three isolated strains and one commercial strain were added to sweet sorghum. Silage was prepared of four treatments and one control with three replicates as control (SKC, adding 2 ml/kg sterilizing water), L. plantarum commercial bacteria (SKP), L. plantarum (HDASK) isolated from King grass (SKA), P. acidilactici (SK3907) isolated from King grass (SKB) and P. acidilactici (ASKDD) isolated from King grass (SKD). All silage were prepared using polyethylene terephthalate bottles, and incubated at room temperature for different ensiling days. The level of pH, acetic acid, NH3-N, water soluble carbohydrate and butyric acid was significantly (P < 0.05) decreased. Lactic acid, ethanol and propionic acid (PA) was significantly (P < 0.05) increased in treatments compared to control. The dry matter, propionic acid neutral detergent fiber, acid detergent fiber did not significantly (P < 0.05) differ among the treatments but the values were increased and decreased. The number of yeast, mold and LAB were significantly (P < 0.05). It is suggested that the supplementation of LAB could enhanced the fermentation quality of sweet Sorghum silage.

Asunto(s)

Fermentación , Lactobacillales/genética , Lactobacillales/aislamiento & purificación , Poaceae/microbiología , Sorghum , Ácido Acético/análisis , Ácido Butírico/análisis , Metabolismo de los Hidratos de Carbono , ADN Bacteriano , Etanol/análisis , Hongos/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis , Ácido Láctico/metabolismo , Lactobacillales/clasificación , Lactobacillales/fisiología , Lactobacillus plantarum/genética , Lactobacillus plantarum/crecimiento & desarrollo , Lactobacillus plantarum/aislamiento & purificación , Lactobacillus plantarum/fisiología , Pediococcus acidilactici/genética , Pediococcus acidilactici/crecimiento & desarrollo , Pediococcus acidilactici/aislamiento & purificación , Pediococcus acidilactici/fisiología , Filogenia , Propionatos/análisis , ARN Ribosómico 16S/genética , Ensilaje/microbiología , Cloruro de Sodio/metabolismo , Temperatura

RESUMEN

Four lactic acid bacteria (LAB) strains isolated from straw silages on the Tibetan Plateau were characterized, and their effects on the fermentation quality of Italian ryegrass (Lolium multiflorum Lam.) at different temperatures (10°C, 15°C and 25°C) were studied. These LAB isolates were evaluated using the acids production ability test, morphological observation, Gram staining, physiological, biochemical and acid tolerance tests. All the isolates (M1, LM8, LO7 and LOG9) could grow at 5-20°C, pH 3.5-7.0 and NaCl (3.0%, 6.5%). Strains M1, LM8, LO7 and LOG9 were identified as Lactobacillus plantarum, L. coryniformis, Pediococcus pentosaceus and P. acidilactici, respectively, by sequencing 16S ribosomal DNA. The four isolates were added to Italian ryegrass for ensiling for 30 days at various temperatures. Compared with the corresponding control, inoculating with isolates M1, LM8 and LO7 could improve the silage quality of Italian ryegrass at low temperatures, indicated by significantly (P < 0.05) higher lactic acid (LA) contents and ratios of lactic acid/acetic acid (LA/AA), and significantly (P < 0.05) lower pH and ammonia nitrogen/total nitrogen (AN/TN). Compared with other isolates, LM8 performed better at 10°C and 15°C, indicated by the higher (P < 0.05) LA content and ratio of LA/AA, and the lower (P < 0.05) pH and AN/TN.

Asunto(s)

Calidad de los Alimentos , Lactobacillales/aislamiento & purificación , Lactobacillus/aislamiento & purificación , Pediococcus acidilactici/aislamiento & purificación , Pediococcus pentosaceus/aislamiento & purificación , Ensilaje , Temperatura , Ácido Acético/análisis , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis , Lactobacillus plantarum/aislamiento & purificación , Lolium , Compuestos de Nitrógeno/análisis , Ensilaje/análisis , Ensilaje/microbiología , Tibet , Factores de Tiempo

RESUMEN

Abstract Pediococcus acidilactici strain S1, a lactic acid-fermenting bacterium, was isolated from makgeolli-a Korean traditional fermented alcoholic beverage. Here we report the 1,980,172 bp (G + C content, 42%) genome sequence of Pediococcus acidilactici strain S1 with 1,525 protein-coding sequences (CDS), of which 47% could be assigned to recognized functional genes. The genome sequence of the strain S1 might provide insights into the genetic basis of the lactic acid bacterium with alcohol-tolerant.

Asunto(s)

Genoma Bacteriano , Ácido Láctico/metabolismo , Bebidas Alcohólicas/microbiología , Pediococcus acidilactici/aislamiento & purificación , Pediococcus acidilactici/genética , Secuencia de Bases , República de Corea , Fermentación , Pediococcus acidilactici/metabolismo , Secuenciación Completa del Genoma

RESUMEN

Pediococcus acidilactici strain S1, a lactic acid-fermenting bacterium, was isolated from makgeolli-a Korean traditional fermented alcoholic beverage. Here we report the 1,980,172bp (G+C content, 42%) genome sequence of Pediococcus acidilactici strain S1 with 1,525 protein-coding sequences (CDS), of which 47% could be assigned to recognized functional genes. The genome sequence of the strain S1 might provide insights into the genetic basis of the lactic acid bacterium with alcohol-tolerant.

Asunto(s)

Bebidas Alcohólicas/microbiología , Genoma Bacteriano , Ácido Láctico/metabolismo , Pediococcus acidilactici/genética , Pediococcus acidilactici/aislamiento & purificación , Secuencia de Bases , Fermentación , Pediococcus acidilactici/metabolismo , República de Corea , Secuenciación Completa del Genoma

RESUMEN

Abstract Pediococcus acidilactici strain K3 is an alcohol-tolerant lactic acid bacterium isolated from nuruk, which is a traditional Korean fermentation starter for makgeolli brewing. Draft genome of this strain was approximately 1,991,399 bp (G+C content, 42.1%) with 1525 protein-coding sequences (CDS), of which 44% were assigned to recognized functional genes. This draft genome sequence data of the strain K3 will provide insights into the genetic basis of its alcohol-tolerance.

Asunto(s)

Adaptación Biológica/efectos de los fármacos , Adaptación Biológica/genética , Genoma Bacteriano , Etanol/farmacología , Pediococcus acidilactici/efectos de los fármacos , Pediococcus acidilactici/genética , Ácido Láctico/biosíntesis , Biología Computacional/métodos , Genómica/métodos , Etanol/metabolismo , Fermentación , Secuenciación de Nucleótidos de Alto Rendimiento , Anotación de Secuencia Molecular , Pediococcus acidilactici/aislamiento & purificación , Pediococcus acidilactici/metabolismo