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1

High hydrostatic pressure inactivation of total aerobic bacteria, lactic acid bacteria, yeasts in sour Chinese cabbage  

Microsoft Academic Search

This study investigated the inactivation of total aerobic bacteria (TAB), lactic acid bacteria (LAB), yeasts in sour Chinese cabbage (SCC) treated by high hydrostatic pressure (HHP). The pressure level ranged from 200 to 600MPa and the treatment time were 10–30min. All samples were stored at 4, 27 and 37°C for 90days. The pressure level of 200MPa had no significant impact

Lin Li; Lun Feng; Junjie Yi; Cheng Hua; Fang Chen; Xiaojun Liao; Zhengfu Wang; Xiaosong Hu

2010-01-01

2

Modeling the effects of sucuk production technique on Listeria monocytogenes, aerobic bacteria and lactic acid bacteria during ripening and storage  

Microsoft Academic Search

The modeling of sucuk (Turkish dry-fermented sausage) production techniques on the survival of Listeria monocytogenes, aerobic bacteria (AB), lactic acid bacteria (LAB), and yeasts and molds (YM) during ripening and storage periods were studied. Effect of L. monocytogenes initially contaminated level (low, medium and high contaminated levels) with sucuk dough was also studied. Survival data were analyzed by non-linear regression

Osman Erkmen

2008-01-01

3

Effects of combining Lactobacillus buchneri 40788 with various lactic acid bacteria on the fermentation and aerobic stability of corn silage  

Microsoft Academic Search

The objective was to compare the effectiveness of combining Lactobacillus buchneri 40788 with three lactic acid bacteria on the fermentation, aerobic stability and nutritive value of corn silage. Freshly chopped whole plant corn was untreated or treated with L. buchneri 40788 paired with Lactobacillus plantarum, Pediococcus acidilactici, or Pediococcus pentosaceus. L. buchneri was added to achieve 4×105CFU\\/g of fresh forage

Lindsey J. Reich; Limin Kung Jr.

2010-01-01

4

Aerobic respiration metabolism in lactic acid bacteria and uses in biotechnology.  

PubMed

The lactic acid bacteria (LAB) are essential for food fermentations and their impact on gut physiology and health is under active exploration. In addition to their well-studied fermentation metabolism, many species belonging to this heterogeneous group are genetically equipped for respiration metabolism. In LAB, respiration is activated by exogenous heme, and for some species, heme and menaquinone. Respiration metabolism increases growth yield and improves fitness. In this review, we aim to present the basics of respiration metabolism in LAB, its genetic requirements, and the dramatic physiological changes it engenders. We address the question of how LAB acquired the genetic equipment for respiration. We present at length how respiration can be used advantageously in an industrial setting, both in the context of food-related technologies and in novel potential applications. PMID:22385163

Pedersen, Martin B; Gaudu, Philippe; Lechardeur, Delphine; Petit, Marie-Agnès; Gruss, Alexandra

2011-11-07

5

Lactic acid bacteria of meat and meat products  

Microsoft Academic Search

When the growth of aerobic spoilage bacteria is inhibited, lactic acid bacteria may become the dominant component of the microbial flora of meats. This occurs with cured meats and with meats packaged in films of low gas permeability. The presence of a flora of psychrotrophic lactic acid bacteria on vacuum-packaged fresh chilled meats usually ensures that shelf-life is maximal. When

Aubrey F. Egan

1983-01-01

6

Effect of inoculation of mesophilic lactic acid bacteria on microbial and sensory changes of minced goat meat during storage under vacuum and subsequent aerobic storage  

Microsoft Academic Search

Minced goat meat inoculated with cell suspensions of Lactococcus lactis ssp lactis (Lc. lactis) or Lactobacillus plantarum was stored under vacuum in PETPE film at 4°C and transferred to aerobic storage for 7 days in LDPE bags. During storage under vacuum, the lactic counts of the inoculated samples dropped followed by the development of spontaneous lactic flora. The pH of

Y. Babji; T. R. K. Murthy

2000-01-01

7

Dry matter and nutritional losses during aerobic deterioration of corn and sorghum silages as influenced by different lactic acid bacteria inocula.  

PubMed

The economic damage that results from aerobic deterioration of silage is a significant problem for farm profitability and feed quality. This paper quantifies the dry matter (DM) and nutritional losses that occur during the exposure of corn and sorghum silages to air over 14 d and assesses the possibility of enhancing the aerobic stability of silages through inoculation with lactic acid bacteria (LAB). The trial was carried out in Northern Italy on corn (50% milk line) and grain sorghum (early dough stage) silages. The crops were ensiled in 30-L jars, without a LAB inoculant (C), with a Lactobacillus plantarum inoculum (LP), and with a Lactobacillus buchneri inoculum (LB; theoretical rate of 1 × 10(6) cfu/g of fresh forage). The pre-ensiled material, the silage at silo opening, and the aerobically exposed silage were analyzed for DM content, fermentative profiles, yeast and mold count, starch, crude protein, ash, fiber components, 24-h and 48-h DM digestibility and neutral detergent fiber (NDF) degradability. The yield and nutrient analysis data of the corn and sorghum silages were used as input for Milk2006 to estimate the total digestible nutrients, net energy of lactation, and milk production per Mg of DM. The DM fermentation and respiration losses were also calculated. The inocula influenced the in vitro NDF digestibility at 24h, the net energy for lactation (NE(L)), and the predicted milk yield per megagram of DM, whereas the length of time of air exposure influenced DM digestibility at 24 and 48 h, the NE(L), and the predicted milk yield per megagram of DM in the corn silages. The inocula only influenced the milk yield per megagram of DM and the air exposure affected the DM digestibility at 24h, the NE(L), and the milk yield per megagram of DM in the sorghum silages. The milk yield, after 14 d of air exposure, decreased to 1,442, 1,418, and 1,277 kg/Mg of DM for C, LB, and LP corn silages, respectively, compared with an average value of 1,568 kg of silage at opening. In the sorghum silages, the milk yield, after 14 d of air exposure, decreased to 1,226, 1,278, and 1,250 kg/Mg of DM for C, LB, and LP, respectively. When the estimated milk yield per megagram of harvested DM of corn and sorghum silage were related to mold count, it was shown that the loss of potential milk production occurred when the mold count exceeded 4 log cfu/g of silage, and it was almost halved when the mold count reached values greater than 8 log cfu/g of silage. Inoculation with L. buchneri, at a rate of 1 × 10(6) cfu/g of fresh forage, enhanced the stability of the silage after exposure to air, and, consequently, contributed to maintaining the nutritional value of the harvested forage over time, for air exposure up to 7 d. PMID:21338806

Tabacco, E; Righi, F; Quarantelli, A; Borreani, G

2011-03-01

8

Genetics of Lactic Acid Bacteria  

NASA Astrophysics Data System (ADS)

Many meat (or fish) products, obtained by the fermentation of meat originating from various animals by the flora that naturally contaminates it, are part of the human diet since millenaries. Historically, the use of bacteria as starters for the fermentation of meat, to produce dry sausages, was thus performed empirically through the endogenous micro-biota, then, by a volunteer addition of starters, often performed by back-slopping, without knowing precisely the microbial species involved. It is only since about 50 years that well defined bacterial cultures have been used as starters for the fermentation of dry sausages. Nowadays, the indigenous micro-biota of fermented meat products is well identified, and the literature is rich of reports on the identification of lactic acid bacteria (LAB) present in many traditional fermented products from various geographical origin, obtained without the addition of commercial starters (See Talon, Leroy, & Lebert, 2007, and references therein).

Zagorec, Monique; Anba-Mondoloni, Jamila; Coq, Anne-Marie Crutz-Le; Champomier-Vergès, Marie-Christine

9

Comparative genomics of the lactic acid bacteria  

Technology Transfer Automated Retrieval System (TEKTRAN)

Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacter...

10

Heme and menaquinone induced electron transport in lactic acid bacteria  

PubMed Central

Background For some lactic acid bacteria higher biomass production as a result of aerobic respiration has been reported upon supplementation with heme and menaquinone. In this report, we have studied a large number of species among lactic acid bacteria for the existence of this trait. Results Heme- (and menaquinone) stimulated aerobic growth was observed for several species and genera of lactic acid bacteria. These include Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacilllus brevis, Lactobacillus paralimentarius, Streptococcus entericus and Lactococcus garviae. The increased biomass production without further acidification, which are respiration associated traits, are suitable for high-throughput screening as demonstrated by the screening of 8000 Lactococcus lactis insertion mutants. Respiration-negative insertion-mutants were found with noxA, bd-type cytochrome and menaquinol biosynthesis gene-disruptions. Phenotypic screening and in silico genome analysis suggest that respiration can be considered characteristic for certain species. Conclusion We propose that the cyd-genes were present in the common ancestor of lactic acid bacteria, and that multiple gene-loss events best explains the observed distribution of these genes among the species.

Brooijmans, Rob; Smit, Bart; Santos, Filipe; van Riel, Jan; de Vos, Willem M; Hugenholtz, Jeroen

2009-01-01

11

Safety of industrial lactic acid bacteria  

Microsoft Academic Search

Lactic acid bacteria (LAB) are ubiquitous in fermented and non-fermented foods and are common components of the human commensal microflora. This long history of human exposure and consumption has led to the reasonable conclusion that they are generally safe. Recent attention has also focused on their possible role as probiotic bacteria, promoting beneficial health effects. There have, however, been a

Martin R. Adams; Surrey GU

1999-01-01

12

Evolutionary Genomics of Lactic Acid Bacteria  

Microsoft Academic Search

The lactic acid bacteria (LAB) might be the most numerous group of bacteria linked to humans. They are naturally asso- ciated with mucosal surfaces, particularly the gastrointestinal tract, and are also indigenous to food-related habitats, includ- ing plant (fruits, vegetables, and cereal grains), wine, milk, and meat environments (60, 61). The LAB include both important pathogens, e.g., several Streptococcus species,

Kira S. Makarova; Eugene V. Koonin

2007-01-01

13

Comparative genomics of the lactic acid bacteria.  

PubMed

Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats. PMID:17030793

Makarova, K; Slesarev, A; Wolf, Y; Sorokin, A; Mirkin, B; Koonin, E; Pavlov, A; Pavlova, N; Karamychev, V; Polouchine, N; Shakhova, V; Grigoriev, I; Lou, Y; Rohksar, D; Lucas, S; Huang, K; Goodstein, D M; Hawkins, T; Plengvidhya, V; Welker, D; Hughes, J; Goh, Y; Benson, A; Baldwin, K; Lee, J-H; Díaz-Muñiz, I; Dosti, B; Smeianov, V; Wechter, W; Barabote, R; Lorca, G; Altermann, E; Barrangou, R; Ganesan, B; Xie, Y; Rawsthorne, H; Tamir, D; Parker, C; Breidt, F; Broadbent, J; Hutkins, R; O'Sullivan, D; Steele, J; Unlu, G; Saier, M; Klaenhammer, T; Richardson, P; Kozyavkin, S; Weimer, B; Mills, D

2006-10-09

14

Comparative genomics of the lactic acid bacteria  

PubMed Central

Lactic acid-producing bacteria are associated with various plant and animal niches and play a key role in the production of fermented foods and beverages. We report nine genome sequences representing the phylogenetic and functional diversity of these bacteria. The small genomes of lactic acid bacteria encode a broad repertoire of transporters for efficient carbon and nitrogen acquisition from the nutritionally rich environments they inhabit and reflect a limited range of biosynthetic capabilities that indicate both prototrophic and auxotrophic strains. Phylogenetic analyses, comparison of gene content across the group, and reconstruction of ancestral gene sets indicate a combination of extensive gene loss and key gene acquisitions via horizontal gene transfer during the coevolution of lactic acid bacteria with their habitats.

Makarova, K.; Slesarev, A.; Wolf, Y.; Sorokin, A.; Mirkin, B.; Koonin, E.; Pavlov, A.; Pavlova, N.; Karamychev, V.; Polouchine, N.; Shakhova, V.; Grigoriev, I.; Lou, Y.; Rohksar, D.; Lucas, S.; Huang, K.; Goodstein, D. M.; Hawkins, T.; Plengvidhya, V.; Welker, D.; Hughes, J.; Goh, Y.; Benson, A.; Baldwin, K.; Lee, J.-H.; Diaz-Muniz, I.; Dosti, B.; Smeianov, V.; Wechter, W.; Barabote, R.; Lorca, G.; Altermann, E.; Barrangou, R.; Ganesan, B.; Xie, Y.; Rawsthorne, H.; Tamir, D.; Parker, C.; Breidt, F.; Broadbent, J.; Hutkins, R.; O'Sullivan, D.; Steele, J.; Unlu, G.; Saier, M.; Klaenhammer, T.; Richardson, P.; Kozyavkin, S.; Weimer, B.; Mills, D.

2006-01-01

15

Production of Menaquinones by Lactic Acid Bacteria  

Microsoft Academic Search

Lactic acid bacteria were examined for their ability to produce quinone compounds, which may include dietary sources of menaquinones. Isoprenyl quinones in bacterial cells grown in a synthetic medium were extracted and analyzed by thin layer chromatography. Lactococcus lactis ssp. cremoris (three strains), Lacto- coccus lactis ssp. lactis (two strains), and Leuconostoc lactis were selected as high producers of quinone

Takashi Morishita; Natsuko Tamura; Takashi Makino; Satoshi Kudo

1999-01-01

16

Probiotic Spectra of Lactic Acid Bacteria (LAB)  

Microsoft Academic Search

Lactic acid bacteria (LAB) and their probio-active cellular substances exert many beneficial effects in the gastrointestinal tract. LAB prevent adherence, establishment, and replication of several enteric mucosal pathogens through several antimicrobial mechanisms. LAB also release various enzymes into the intestinal lumen and exert potential synergistic effects on digestion and alleviate symptoms of intestinal malabsoption. Consumption of LAB fermented dairy products

A. S. Naidu; W. R. Bidlack; R. A. Clemens

1999-01-01

17

Genomic organization of lactic acid bacteria  

Microsoft Academic Search

Current knowledge of the genomes of the lactic acid bacteria, Lactococcus lactis and Streptococcus thermophilus, and members of the genera Lactobacillus, Leuconostoc, Pediococcus and Carnobacterium is reviewed. The genomes contain a chromosome within the size range of 1.8 to 3.4 Mbp. Plasmids are common in Lactococcus lactis (most strains carry 4–7 different plasmids), some of the lactobacilli and pediococci, but

Barrie E. Davidson; Nancy Kordias; Marian Dobos; Alan J. Hillier

1996-01-01

18

Carbohydrate metabolism in lactic acid bacteria  

Microsoft Academic Search

The term “lactic acid bacteria” is discussed. An overview of the following topics is given: main pathways of homo- and heterofermentation of hexoses, i.e. glycolysis, bifidus pathway, 6-phosphogluconate pathway; uptake and dissimilation of lactose (tagatose pathway); fermentation of pentoses and pentitols; alternative fates of pyruvate, i.e. splitting to formate and acetate, CO2 and acetate or formation of acetoin and diacetyl;

Otto Kandler

1983-01-01

19

Aerobic Succinate Production in Bacteria.  

National Technical Information Service (NTIS)

Methods of increasing yields of succinate using aerobic culture methods and a multi-mutant E. coli strain are provided. Also provided is a mutant strain of E. coli that produces high amounts of succinic acid.

G. N. Bennett H. Lin K. Y. San

2004-01-01

20

Bacteriocins of lactic acid bacteria: Their potentials as food biopreservative  

Microsoft Academic Search

Numerous strains of lactic acid bacteria used in the fermentation of foods are known to produce bacteriocins. In general, bacteriocins are a group of proteinaceous antimicrobial substances that inhibit the growth of closely related bacteria. However, some bacteriocins produced by lactic acid bacteria (LAB) exhibit a relatively broad antimicrobial spectrum and are active against several food?spoilage and health?threatening microorganisms. Many

Wang June Kim

1993-01-01

21

Fermentation of beet juice by beneficial lactic acid bacteria  

Microsoft Academic Search

Red beets were evaluated as a potential substrate for the production of probiotic beet juice by four species of lactic acid bacteria (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus delbrueckii, Lactobacillus plantarum). All the lactic cultures were found capable of rapidly utilizing beet juice for cell synthesis and lactic acid production. However, L. acidophilus and L. plantarum produced a greater amount of

Kyung Young Yoon; Edward E. Woodams; Yong D. Hang

2005-01-01

22

Lactic acid bacteria and the human gastrointestinal tract  

Microsoft Academic Search

Objective: This review summarises the effects of lactic acid bacteria on lactose malabsorption, bacterial\\/viral or antibiotic associated diarrhoea, and describes the impact of lactic acid bacteria on cancer and the fermentative products in the colon.Results: Eight studies (including 78 patients) demonstrated that lactase deficient subjects absorbed lactose in yogurt better than lactose in milk, while two studies (25 patients) did

H Hove; H Nørgaard; P Brøbech Mortensen

1999-01-01

23

Occurrence and role of lactic acid bacteria in seafood products.  

PubMed

Lactic acid bacteria (LAB) in fish flesh has long been disregarded because the high post-mortem pH, the low percentage of sugars, the high content of low molecular weight nitrogenous molecules and the low temperature of temperate waters favor the rapid growth of pH-sensitive psychrotolerant marine Gram-negative bacteria like Pseudomonas, Shewanella and Photobacterium. In seafood packed in both vacuum (VP) and modified atmosphere (MAP) packaging commonly CO(2) enriched, the growth of the Gram-negative aerobic bacteria group (predominantly pseudomonads) is effectively inhibited and the number reached by LAB during storage is higher than that achieved in air but always several log units lower than the trimethylamine oxide (TMA-O) reducing and CO(2)-resistant organisms (Shewanella putrefaciens and Photobacterium phosphoreum). Accordingly, LAB are not of much concern in seafood neither aerobically stored nor VP and MAP. However, they may acquire great relevance in lightly preserved fish products (LPFP), including those VP or MAP. Fresh fish presents a very high water activity (aw) value (0.99). However, aw is reduced to about 0.96 when salt (typically 6% WP) is added to the product. As a result, aerobic Gram-negative bacteria are inhibited, which allows the growth of other organisms more resistant to reduced aw, i.e. LAB, and then they may acquire a central role in the microbial events occurring in the product. Changes in consumers' habits have led to an increase of convenient LPFP with a relative long shelf-life (at least 3 weeks) which, on the other hand, may constitute a serious problem from a safety perspective since Listeria monocytogenes and sometimes Clostridium botulinum (mainly type E) may able to grow. In any case the LAB function in marine products is complex, depending on species, strains, interaction with other bacteria and the food matrix. They may have no particular effect or they may be responsible for spoilage and, in certain cases, they may even exert a bioprotective effect in relation to undesirable bacteria. The bioprotective potential of endogenous LAB in relation to pathogens and spoiling bacteria has often been highlighted. However, the technology is still in its infancy compared with foods dairy and meat products in which either the carbohydrate content (dairy products) or sugar and salt added (meat products) favor the acidification by LAB that enable a natural preservation of the product. Successful studies on LAB as probiotic for fish intensify, but this potential is still to be explored for human. Although not usual, some applications of LAB for fermentation of marine products and by-products are described. PMID:20630312

Françoise, Leroi

2010-05-25

24

High efficiency recombineering in lactic acid bacteria  

PubMed Central

The ability to efficiently generate targeted point mutations in the chromosome without the need for antibiotics, or other means of selection, is a powerful strategy for genome engineering. Although oligonucleotide-mediated recombineering (ssDNA recombineering) has been utilized in Escherichia coli for over a decade, the successful adaptation of ssDNA recombineering to Gram-positive bacteria has not been reported. Here we describe the development and application of ssDNA recombineering in lactic acid bacteria. Mutations were incorporated in the chromosome of Lactobacillus reuteri and Lactococcus lactis without selection at frequencies ranging between 0.4% and 19%. Whole genome sequence analysis showed that ssDNA recombineering is specific and not hypermutagenic. To highlight the utility of ssDNA recombineering we reduced the intrinsic vancomymycin resistance of L. reuteri >100-fold. By creating a single amino acid change in the d-Ala-d-Ala ligase enzyme we reduced the minimum inhibitory concentration for vancomycin from >256 to 1.5?µg/ml, well below the clinically relevant minimum inhibitory concentration. Recombineering thus allows high efficiency mutagenesis in lactobacilli and lactococci, and may be used to further enhance beneficial properties and safety of strains used in medicine and industry. We expect that this work will serve as a blueprint for the adaptation of ssDNA recombineering to other Gram-positive bacteria.

van Pijkeren, Jan-Peter; Britton, Robert A.

2012-01-01

25

Bioconversion of oleuropein to hydroxytyrosol by lactic acid bacteria.  

PubMed

The aim of this work is to study the conversion of oleuropein-a polyphenol present in olives and olive oil by-products-into hydroxytyrosol, a polyphenol with antioxidant and antibacterial properties. The hydrolysis reaction is performed by lactic acid bacteria. Six bacterial strains (Lactobacillus plantarum 6907, Lactobacillus paracasei 9192, Lactobacillus casei, Bifidobacterium lactis BO, Enterococcus faecium 32, Lactobacillus LAFTI 10) were tested under aerobic and anaerobic conditions. The oleuropein degradation and hydroxytyrosol formation were monitored by HPLC. Results showed that oleuropein could be successfully converted into hydroxytyrosol. The most effective strain was Lactobacillus plantarum 6907, with a reaction yield of hydroxytyrosol of about 30 %. Different reaction mechanisms were observed for different microorganisms; a different yield was observed for Lactobacillus paracasei 9192 under aerobic or anaerobic conditions and an intermediate metabolite (oleuropein aglycone) was detected for Lactobacillus paracasei 9192 and Lactobacillus plantarum 6907 only. This study could have significant applications, as this reaction can be used to increase the value of olive oil by-products and/or to improve the taste of unripe olives. PMID:22806118

Santos, M M; Piccirillo, C; Castro, P M L; Kalogerakis, N; Pintado, M E

2012-03-20

26

Hydrogen Peroxide Formation and Catalase Activity in the Lactic Acid Bacteria  

Microsoft Academic Search

SUMMARY Some lactic acid bacteria formed detectable H202 and some did not, regardless of their preference or requirement for aerobic or anaerobic conditions. Whether or not H202 was formed depended in some instances on the substrate used as energy source. Two H202-splitting activities were encountered though never in the same organism. One, named pseudo- catalase activity, was insensitive to 0.01

R. Whittenbury

1964-01-01

27

Microbiological quality assessment of Moroccan camel's milk and identification of predominating lactic acid bacteria  

Microsoft Academic Search

Samples of camel's milk collected from different zones of Morocco were analysed to evaluate their microbiological quality and to identify predominating lactic acid bacteria (LAB). The following average colony-forming units (c.f.u.s) of aerobic total count, enterococci, faecal and total coliforms, LAB, yeasts,Staphylococcus aureus and spores of sulphite-reducing clostridia were recorded: 6.2 × 107, 2.9 × 104, 1.6 × 104, 7.0

N. Benkerroum; A. Boughdadi; N. Bennani; K. Hidane

2003-01-01

28

Identification of Lactic Acid Bacteria in Michigan Cherry Wines  

Microsoft Academic Search

Many factors contribute to the final flavor of wine. One factor is malolactic fermentation, during which lactic acid bacteria (LAB) transform the harsh tasting malic acid into a more drinkable lactic acid in grape wine. The role of LAB in the production of cherry wine is completely unknown. The goal of this study is to identify the species of LAB

Emily Henk; Margaret Dietrich; Terri Weese

2008-01-01

29

Stress responses in lactic acid bacteria.  

PubMed

Lactic acid bacteria (LAB) constitute a heterogeneous group of bacteria that are traditionally used to produce fermented foods. The industrialization of food bio-transformations increased the economical importance of LAB, as they play a crucial role in the development of the organoleptique and hygienic quality of fermented products. Therefore, the reliability of starter strains in terms of quality and functional properties (important for the development of aroma and texture), but also in terms of growth performance and robustness has become essential. These strains should resist to adverse conditions encountered in industrial processes, for example during starter handling and storage (freeze-drying, freezing or spray-drying). The development of new applications such as life vaccines and probiotic foods reinforces the need for robust LAB since they may have to survive in the digestive tract, resist the intestinal flora, maybe colonize the digestive or uro-genital mucosa and express specific functions under conditions that are unfavorable to growth (for example, during stationary phase or storage). Also in nature, the ability to quickly respond to stress is essential for survival and it is now well established that LAB, like other bacteria, evolved defense mechanisms against stress that allow them to withstand harsh conditions and sudden environmental changes. While genes implicated in stress responses are numerous, in LAB the levels of characterization of their actual role and regulation differ widely between species. The functional conservation of several stress proteins (for example, HS proteins, Csp, etc) and of some of their regulators (for example, HrcA, CtsR) renders even more striking the differences that exist between LAB and the classical model micro-organisms. Among the differences observed between LAB species and B. subtilis, one of the most striking is the absence of a sigma B orthologue in L. lactis ssp. lactis as well as in at least two streptococci and probably E. faecalis. The overview of LAB stress responses also reveals common aspects of stress responses. As in other bacteria, adaptive responses appear to be a usual mode of stress protection in LAB. However, the cross-protection to other stress often induced by the expression of a given adaptive response, appears to vary between species. This observation suggests that the molecular bases of adaptive responses are, at least in part, species (or even subspecies) specific. A better understanding of the mechanisms of stress resistance should allow to understand the bases of the adaptive responses and cross protection, and to rationalize their exploitation to prepare LAB to industrial processes. Moreover, the identification of crucial stress related genes will reveal targets i) for specific manipulation (to promote or limit growth), ii) to develop tools to screen for tolerant or sensitive strains and iii) to evaluate the fitness and level of adaptation of a culture. In this context, future genome and transcriptome analyses will undoubtedly complement the proteome and genetic information available today, and shed a new light on the perception of, and the response to, stress by lactic acid bacteria. PMID:12369188

van de Guchte, Maarten; Serror, Pascale; Chervaux, Christian; Smokvina, Tamara; Ehrlich, Stanislav D; Maguin, Emmanuelle

2002-08-01

30

Treatments Using Hot Water Instead of Lactic Acid Reduce Levels of Aerobic Bacteria and Enterobacteriaceae and Reduce the Prevalence of Escherichia coli O157:H7 on Preevisceration Beef Carcasses  

Microsoft Academic Search

Lactic acid has become the most commonly used organic acid for treatment of postevisceration beef carcasses. Many processors have also implemented 2% lactic acid washes on preevisceration carcasses. We previously demonstrated that hot water washing and steam vacuuming are effective carcass interventions. Because of the effectiveness of hot water, we compared its use with that of lactic acid as a

JOSEPH M. BOSILEVAC; XIANGWU NOU; GENEVIEVE A. BARKOCY-GALLAGHER; TERRANCE M. ARTHUR; MOHAMMAD KOOHMARAIE

2006-01-01

31

Production of Value-added Products by Lactic Acid Bacteria  

Technology Transfer Automated Retrieval System (TEKTRAN)

Lactic acid bacteria (LAB) are a group of facultative anaerobic, catalase negative, nonmotile and nonsporeforming–Gram positive bacteria. Most LAB utilize high energy C sources including monomer sugars to produce energy to maintain cellular structure and function. This anaerobic fermentation proce...

32

Diversity of lactic acid bacteria of the bioethanol process  

Microsoft Academic Search

BACKGROUND: Bacteria may compete with yeast for nutrients during bioethanol production process, potentially causing economic losses. This is the first study aiming at the quantification and identification of Lactic Acid Bacteria (LAB) present in the bioethanol industrial processes in different distilleries of Brazil. RESULTS: A total of 489 LAB isolates were obtained from four distilleries in 2007 and 2008. The

Brigida TL Lucena; Billy M dos Santos; João LS Moreira; Ana Paula B Moreira; Alvaro C Nunes; Vasco Azevedo; Anderson Miyoshi; Fabiano L Thompson; Marcos de Morais

2010-01-01

33

Lactic acid bacteria - a new tool for medicine and pharmacology?  

Microsoft Academic Search

Lactic acid bacteria are a heterogeneous and highly diverse group of microorganisms classified with the status GRAS (Generally Regarded As Safe), meaning that they do not cause illness in humans. They play and important economic role - having been used in the basic production of foods and animal feeds for several millennia. Nowadays such bacteria are being harnessed ever more

JACEK BARDOWSKI

34

Comparative analysis of CRISPR loci in lactic acid bacteria genomes  

Microsoft Academic Search

Clustered regularly interspaced short palindromic repeats (CRISPR) are hypervariable loci widely distributed in bacteria and archaea, that provide acquired immunity against foreign genetic elements. Here, we investigate the occurrence of CRISPR loci in the genomes of lactic acid bacteria (LAB), including members of the Firmicutes and Actinobacteria phyla. A total of 102 complete and draft genomes across 11 genera were

Philippe Horvath; Anne-Claire Coûté-Monvoisin; Dennis A. Romero; Patrick Boyaval; Christophe Fremaux; Rodolphe Barrangou

2009-01-01

35

Biology of Moderately Halophilic Aerobic Bacteria  

PubMed Central

The moderately halophilic heterotrophic aerobic bacteria form a diverse group of microorganisms. The property of halophilism is widespread within the bacterial domain. Bacterial halophiles are abundant in environments such as salt lakes, saline soils, and salted food products. Most species keep their intracellular ionic concentrations at low levels while synthesizing or accumulating organic solutes to provide osmotic equilibrium of the cytoplasm with the surrounding medium. Complex mechanisms of adjustment of the intracellular environments and the properties of the cytoplasmic membrane enable rapid adaptation to changes in the salt concentration of the environment. Approaches to the study of genetic processes have recently been developed for several moderate halophiles, opening the way toward an understanding of haloadaptation at the molecular level. The new information obtained is also expected to contribute to the development of novel biotechnological uses for these organisms.

Ventosa, Antonio; Nieto, Joaquin J.; Oren, Aharon

1998-01-01

36

Synthesis of the Cancer Preventive Peptide Lunasin by Lactic Acid Bacteria During Sourdough Fermentation  

Microsoft Academic Search

This study aimed to exploit the potential of sourdough lactic acid bacteria to release lunasin during fermentation of cereal and nonconventional flours. The peptidase activities of a large number of sourdough lactic acid bacteria were screened using synthetic substrates. Selected lactic acid bacteria were used as sourdough starters to ferment wholemeal wheat, soybean, barley, amaranth, and rye flours. Proteinase activity

Carlo G. Rizzello; Luana Nionelli; Rossana Coda; Marco Gobbetti

2011-01-01

37

Synthesis of the Cancer Preventive Peptide Lunasin by Lactic Acid Bacteria During Sourdough Fermentation  

Microsoft Academic Search

This study aimed to exploit the potential of sourdough lactic acid bacteria to release lunasin during fermentation of cereal and nonconventional flours. The peptidase activities of a large number of sourdough lactic acid bacteria were screened using synthetic substrates. Selected lactic acid bacteria were used as sourdough starters to ferment wholemeal wheat, soybean, barley, amaranth, and rye flours. Proteinase activity

Carlo G. Rizzello; Luana Nionelli; Rossana Coda; Marco Gobbetti

2012-01-01

38

Barriers to application of genetically modified lactic acid bacteria  

Microsoft Academic Search

To increase the acceptability of food products containing genetically modified microorganisms it is necessary to provide in an early stage to the consumers that the product is safe and that the product provide a clear benefit to the consumer. To comply with the first requirement a systematic approach to analyze the probability that genetically modified lactic acid bacteria will transform

C. T. Verrips; D. J. C. Berg

1996-01-01

39

Lactic acid bacteria in traditional fermented Chinese foods  

Microsoft Academic Search

Food fermentation is a widely practiced and ancient technology in China. Lactic acid bacteria (LAB) are involved in many fermentation processes of Chinese traditional foods, demonstrating their profound effects on improving food quality and food safety. This review article outlines the main types of LAB fermentation as well as their typical fermented foods such as koumiss, suan-tsai, stinky tofu and

Shan-na Liu; Ye Han; Zhi-jiang Zhou

2011-01-01

40

Lactic acid bacteria in a changing legislative environment  

Microsoft Academic Search

The benefits of using lactic acid bacteria in the food chain, both through direct consumption and production of ingredients, are increasingly recognised by the food industry and consumers alike. The regulatory environment surrounding these products is diverse, covering foods and food ingredients, processing aids, feed additives and dietary supplements. On a global basis, there are different approaches taken by the

Jean Feord

2002-01-01

41

Bacteriocins from Lactic Acid Bacteria: Production, Purification, and Food Applications  

Microsoft Academic Search

In fermented foods, lactic acid bacteria (LAB) display numerous antimicrobial activities. This is mainly due to the production of organic acids, but also of other compounds, such as bacteriocins and antifungal peptides. Several bacteriocins with industrial potential have been purified and characterized. The kinetics of bacteriocin production by LAB in relation to process factors have been studied in detail through

Luc De Vuyst; Frédéric Leroy

2007-01-01

42

New ways of selecting lactic acid bacteria for biotechnological processes  

Microsoft Academic Search

Illustrated by the selection of lactic acid bacteria to be used as biological ensilage agents, new methods are introduced; they are practicable in microtitre plate dimensions by means of an automatic analysing system. According to the test setting, statements can be made on the acidifiability, the inhibition effect on contaminants and the growth under different milieu conditions. Of 126 strains

Joachim Venus; Frank Idler; Christine Albrecht

1992-01-01

43

Phylogenomic reconstruction of lactic acid bacteria: an update  

Microsoft Academic Search

BACKGROUND: Lactic acid bacteria (LAB) are important in the food industry for the production of fermented food products and in human health as commensals in the gut. However, the phylogenetic relationships among LAB species remain under intensive debate owing to disagreements among different data sets. RESULTS: We performed a phylogenetic analysis of LAB species based on 232 genes from 28

Zhi-Gang Zhang; Zhi-Qiang Ye; Li Yu; Peng Shi

2011-01-01

44

Taxonomy and physiology of probiotic lactic acid bacteria  

Microsoft Academic Search

The current taxonomy of probiotic lactic acid bacteria is reviewed with special focus on the genera Lactobacillus, Bifidobacterium and Enterococcus. The physiology and taxonomic position of species and strains of these genera were investigated by phenotypic and genomic methods. In total, 176 strains, including the type strains, have been included. Phenotypic methods applied were based on biochemical, enzymatical and physiological

Günter Klein; Alexander Pack; Christine Bonaparte; Gerhard Reuter

1998-01-01

45

Isolation of a new lytic enzyme for hiochi bacteria and other lactic acid bacteria  

Microsoft Academic Search

A microorganism producing a lytic enzyme preparation that could rapidly lyse bacterial cells such as hiochi bacteria and other lactic acid bacteria was screened. The microorganism was identified as Streptomyces fulvissimus. The enzyme produced by this organism lysed boil-denatured cells quicker than intact cells of hiochi bacteria. A mutant strain of S. fulvissimus producing the enzyme exhibiting high activity against

Kazuhiko Ohbuchi; Kazuya Hasegawa; Masaaki Hamachi; Kenji Ozeki; Chieko Kumagai

2001-01-01

46

Occurrence and role of lactic acid bacteria in seafood products  

Microsoft Academic Search

Lactic acid bacteria (LAB) in fish flesh has long been disregarded because the high post-mortem pH, the low percentage of sugars, the high content of low molecular weight nitrogenous molecules and the low temperature of temperate waters favor the rapid growth of pH-sensitive psychrotolerant marine Gram-negative bacteria like Pseudomonas, Shewanella and Photobacterium. In seafood packed in both vacuum (VP) and modified atmosphere

Leroi Françoise

2010-01-01

47

Lantibiotics produced by lactic acid bacteria: structure, function and applications  

Microsoft Academic Search

Lantibiotics are a diverse group of heavily modified antimicrobial and\\/or signalling peptides produced by a wide range of bacteria, including a variety of lactic acid bacteria. Based on their diverse structures and mode of action, at least six separate lantibiotic subgroups can be suggested, but all subgroups are characterized by significant post-translational modifications, which include the formation of (ß-methyl)lanthionines, among

Denis Twomey; R. P. Ross; Maire Ryan; Billy Meaney; C. Hill

2002-01-01

48

Perspectives of engineering lactic acid bacteria for biotechnological polyol production  

Microsoft Academic Search

Polyols are sugar alcohols largely used as sweeteners and they are claimed to have several health-promoting effects (low-caloric,\\u000a low-glycemic, low-insulinemic, anticariogenic, and prebiotic). While at present chemical synthesis is the only strategy able\\u000a to assure the polyol market demand, the biotechnological production of polyols has been implemented in yeasts, fungi, and\\u000a bacteria. Lactic acid bacteria (LAB) are a group of

Vicente Monedero; Gaspar Pérez-Martínez; María J. Yebra

2010-01-01

49

Molecular biology of oxygen tolerance in lactic acid bacteria: Functions of NADH oxidases and Dpr in oxidative stress  

Microsoft Academic Search

Lactic acid bacteria including Streptococcus mutans lack cytochromes and heme-containing proteins. Most lactic acid bacteria also lack catalase. However, they can grow in the presence of air. In view of the defense against oxygen toxicity, the lack of catalase in lactic acid bacteria is not always consistent with its aerotolerance. Mechanisms, by which lactic acid bacteria establish their growth in

Masako Higuchi; Yuji Yamamoto; Yoshiyuki Kamio

2000-01-01

50

Isolation, screening and identification of lactic acid bacteria from traditional food fermentation processes and culture collections  

Microsoft Academic Search

This study describes a search for lactic acid bacteria capable of exo?polysaccharide production or exhibiting antimicrobial or proteolytic activities. About 400 lactic acid bacteria were isolated from traditional fermented foods (sour dough, sausages, table olives, cheese and other dairy products). Together with almost 200 lactic acid bacterial strains obtained from culture collections, these strains were screened for exo?polysaccharide production, bacteriocin

Dick J. C. van den Berg; Annelies Smits; Bruno Pot; Aat M. Ledeboer; Karel Kersters; John M. A. Verbake; C. Theo Verrips

1993-01-01

51

Method for the preparation of stabile microencapsulated lactic acid bacteria  

Microsoft Academic Search

Summary A method to produce viable and stabile dry microorganisms for food and agricultural purposes was developed. Spray-dried, freeze-dried or liquid culture concentrates of lactic acid-producing bacteria were mixed with various bulking agents to form a homogeneous wet granulation having a water content of 35–60% (w\\/w). The wet granulation was extruded through a dye onto a spinning plate (350–500 rpm)

H. S. Kim; B. J. Kamara; I. C. Good; G. L. Enders

1988-01-01

52

Lactic acid bacteria as adjuvants for sublingual allergy vaccines  

Microsoft Academic Search

We compared immunomodulatory properties of 11 strains of lactic acid bacteria as well as their capacity to enhance sublingual immunotherapy efficacy in a murine asthma model. Two types of bacterial strains were identified, including: (i) potent inducers of IL-12p70 and IL-10 in dendritic cells, supporting IFN-? and IL-10 production in CD4+ T cells such as Lactobacillus helveticus; (ii) pure Th1

Laurence Van Overtvelt; Helene Moussu; Stéphane Horiot; Sandrine Samson; Vincent Lombardi; Laurent Mascarell; Ariane van de Moer; Raphaëlle Bourdet-Sicard; Philippe Moingeon

2010-01-01

53

Fermentation of pomegranate juice by probiotic lactic acid bacteria  

Microsoft Academic Search

In this research, production of probiotic pomegranate juice through its fermentation by four strains of lactic acid bacteria:\\u000a Lactobacillus plantarum, L. delbruekii, L. paracasei, L. acidophilus was examined. Fermentation was carried out at 30°C for 72 h under microaerophilic conditions. Microbial population, pH, titrable\\u000a acidity, sugar and organic acid metabolism were measured during the fermentation period and the viability of all

Z. E. Mousavi; S. M. Mousavi; S. H. Razavi; Z. Emam-Djomeh; H. Kiani

2011-01-01

54

Survival of Staphylococcus aureus and aerobic bacteria in sucuks made from starter culture and Thymbra spicata during manufacturing and storage  

Microsoft Academic Search

Sucuk (a kind of dry-fermented Turkish sausage) dough was inoculated with Staphylococcus aureus at a level of 3.74 log colony forming unit (cfu) g?1 and manufactured in the presence of spices and addition of lactic acid bacteria (LAB) and with and without essential oil of Thymbra spicata. All samples were analyzed for S. aureus, aerobic plate count (APC), LAB and

Osman Erkmen

2009-01-01

55

Soil and Sediment Bacteria Capable of Aerobic Nitrate Respiration  

Microsoft Academic Search

Several laboratory strains of gram-negative bacteria are known to be able to respire nitrate in the presence ofoxygen,althoughthephysiologicaladvantagegainedfromthisprocessisnotentirelyclear.Thecontribution that aerobic nitrate respiration makes to the environmental nitrogen cycle has not been studied. As afirst step in addressing this question, a strategy which allows for the isolation of organisms capable of reducing nitrate to nitrite following aerobic growth has been developed.

JON P. CARTER; YA HSIN HSIAO; STEPHEN SPIRO; ANDDAVID J. RICHARDSON

1995-01-01

56

Aerobic, Endospore-Forming Bacteria from Antarctic Geothermal Soils  

Microsoft Academic Search

The term ‘aerobic endospore-forming bacteria’ is used to embrace Bacillus species and related genera, for which the production of resistant endospores in the presence of oxygen remains the defining\\u000a feature. They are also expected to possess Gram-positive cell wall structures (but staining reactions, even in young cultures,\\u000a may be Gram-variable or frankly Gram-negative), and may be aerobic or facultatively anaerobic.

Niall A. Logan A. Logan; Raymond N. Allan N. Allan

57

Lactic acid bacteria with health claims—interactions and interference with gastrointestinal flora  

Microsoft Academic Search

Lactic acid bacteria in foods have a long history of safe use. Members of the genera Lactococcus and Lactobacillus have a ‘generally-recognised-as-safe’ status, whilst members of the genera Streptococcus and Enterococcus and some other genera of lactic acid bacteria contain opportunistic pathogens. New species and more specific strains of probiotic bacteria are constantly being identified. Prior to incorporating new strains

Tiina Mattila-Sandholm; Jaana Mättö; Maria Saarela

1999-01-01

58

Antimicrobial Activity of Lactic Acid Bacteria from Sour Milk Products Narine, Karine, and Matsun  

Microsoft Academic Search

We studied antimicrobial properties of lactic acid bacteria from sour milk products Narine, Karine, and Matsun. The whey of the sour milk products included two major fractions, of sugars and L-lactic acid and its sodium and calcium salts. Antimicrobial activity of Narine, Karine, and Matsun was related to the presence of L-lactic acid and its sodium and calcium salts.

A. O. Martirosyan; Sh. L. Mndzhoyan; L. M. Charyan; L. G. Akopyan; M. N. Nikishchenko

2004-01-01

59

Growth and survival of lactic acid bacteria in lucerne silage.  

PubMed

A rifampicin-resistant variant of two strains of Lactobacillus plantarum, one strain of Pediococcus acidilactici, and one strain of Enterococcus faecium were used for the experimental production of lucerne silage. Laboratory silage without inoculants served as a control. Counts of total anaerobes, total lactic acid bacteria (LAB), lactobacilli, pediococci, and enterococci were determined on days 14, 21, 30, 49, and 60 of lucerne fermentation. LAB dominated in silage microflora, reaching a percentage between 59 and 95 % of total anaerobes. Lactobacilli were found as a predominant group of LAB during the whole study. Lactobacilli reached numbers 8.74 log CFU/g in treated silage and 8.89 log CFU/g in the control at the first observation. Their counts decreased to 4.23 and 4.92 log CFU/g in treated silage and the control, respectively, on day 63 of fermentation. Similar decreases were observed in all bacterial groups. The treated silage samples possessed lower pH (4.2 vs. 4.5 in control samples) and contained more lactic acid compared to control silage. The identity of re-isolated rifampicin-resistant bacteria with those inoculated to the lucerne was evaluated by fingerprinting techniques. The fingerprint profiles of re-isolated bacteria corresponded to the profiles of strains used for the treatment. It could be concluded that supplemented LAB dominated in laboratory silage and overgrew naturally occurring LAB. PMID:22491990

Vlková, Eva; Rada, Vojt?ch; Bunešová, V?ra; Ro?ková, Sárka

2012-04-11

60

AEROBIC SALIVARY BACTERIA IN WILD AND CAPTIVE KOMODO DRAGONS  

Microsoft Academic Search

During the months of November 1996, August 1997, and March 1998, saliva and plasma samples were collected for isolation of aerobic bacteria from 26 wild and 13 captive Komodo dragons (Varanus komodoensis). Twenty-eight Gram-negative and 29 Gram-positive spe- cies of bacteria were isolated from the saliva of the 39 Komodo dragons. A greater number of wild than captive dragons were

Joel M. Montgomery; Don Gillespie; Putra Sastrawan; Terry M. Fredeking; George L. Stewart

2002-01-01

61

Oxygen tolerance of strictly aerobic hydrogen-oxidizing bacteria  

Microsoft Academic Search

Growth of various bacteria, especially aerobic hydrogen-oxidizing bacteria, in the presence of 2 to 100% (v\\/v) oxygen in the gas atmosphere was evaluated. The bacterial strains included Alcaligenes eutrophus, A. paradoxus, Aquaspirillum autotrophicum, Arthrobacter spec. strain 11X, Escherichia coli, Arthrobacter globiformis, Nocardia opaca, N. autotrophica, Paracoccus denitrificans, Pseudomonas facilis, P. putida, and Xanthobacter autotrophicus. Under heterotrophic conditions with fructose or

E. Wilde; H. G. Schlegel

1982-01-01

62

Production, recovery and purification of bacteriocins from lactic acid bacteria  

Microsoft Academic Search

Bacteriocins produced by lactic acid bacteria are a heterogeneous group of peptide inhibitors which include lantibiotics\\u000a (class I, e.g. nisin), small heat-stable peptides (class II, e.g. pediocin AcH\\/PA1) and large heat-labile proteins (class\\u000a III, e.g. helveticin J). Many bacteriocins belonging to the first two groups can be successfully used to inhibit undesirable\\u000a microorganisms in foods, but only nisin is produced

E. Parente; A. Ricciardi

1999-01-01

63

Aerobic methanol-oxidizing bacteria in soil.  

PubMed

Methanol is an atmospheric compound that is primarily released from plant polymers and impacts ozone formation. The global methanol emission rate from terrestrial ecosystems is of the same order of magnitude (4.9 x 10(12) mol year(-1)) as that of methane (10 x 10(12) mol year(-1)). The major proportion of the annual plant-released methanol does not enter the atmosphere, but may be reoxidized by biological methanol oxidation, which is catalyzed by methanol-oxidizing prokaryotes. Fifty-six aerobic methanol-oxidizing species have been isolated from soils. These methylotrophs belong to the Alpha-, Beta-, and Gammaproteobacteria, Verrucomicrobia, Firmicutes, and Actinobacteria. Their ecological niches are determined by oxygen and methanol concentration, temperature, pH, the capability to utilize nitrate as an electron acceptor, and the spectrum of nitrogen sources and utilizable multicarbon substrates. Recently discovered interactions with eukaryotes indicate that their ecological niches may not solely be defined by physicochemical parameters. Nonetheless, there are still gaps in knowledge; based on global methanol budgets, methanol oxidation in soil is important, but has not been addressed adequately by biogeochemical studies. Ratios of above-ground and soil-internal methanol oxidation are not known. The contribution to methanol-oxidation by aerobic and anaerobic methylotrophs in situ also needs further research. PMID:19583792

Kolb, Steffen

2009-07-01

64

Engineering strategies aimed at control of acidification rate of lactic acid bacteria.  

PubMed

The ability of lactic acid bacteria to produce lactic acid from various sugars plays an important role in food fermentations. Lactic acid is derived from pyruvate, the end product of glycolysis and thus a fast lactic acid production rate requires a high glycolytic flux. In addition to lactic acid, alternative end products--ethanol, acetic acid and formic acid--are formed by many species. The central role of glycolysis in lactic acid bacteria has provoked numerous studies aiming at identifying potential bottleneck(s) since knowledge about flux control could be important not only for optimizing food fermentation processes, but also for novel applications of lactic acid bacteria, such as cell factories for the production of green fuels and chemicals. With respect to the control and regulation of the fermentation mode, some progress has been made, but the question of which component(s) control the main glycolytic flux remains unanswered. PMID:23266099

Martinussen, Jan; Solem, Christian; Holm, Anders Koefoed; Jensen, Peter Ruhdal

2012-12-19

65

Inhibition of citrus fungal pathogens by using lactic acid bacteria.  

PubMed

The effect of lactic acid bacteria (LAB) on pathogenic fungi was evaluated and the metabolites involved in the antifungal effect were characterized. Penicillium digitatum (INTA 1 to INTA 7) and Geotrichum citri-aurantii (INTA 8) isolated from decayed lemon from commercial packinghouses were treated with imazalil and guazatine to obtain strains resistant to these fungicides. The most resistant strains (4 fungal strains) were selected for evaluating the antifungal activity of 33 LAB strains, among which only 8 strains gave positive results. The antifungal activity of these LAB strains was related to the production of lactic acid, acetic acid, and phenyllactic acid (PLA). A central composite design and the response surface methodology were used to evaluate the inhibitory effect of the organic acids produced by the LAB cultures. The antifungal activity of lactic acid was directly related to its concentration; however, acetic acid and PLA showed a peak of activity at 52.5 and 0.8 mM, respectively, with inhibition rates similar to those obtained with Serenade((R)) (3.0 ppm) imazalil (50 ppm) and guazatine (50 ppm). Beyond the peak of activity, a reduction in effectiveness of both acetic acid and PLA was observed. Comparing the inhibition rate of the organic acids, PLA was about 66- and 600-fold more effective than acetic acid and lactic acid, respectively. This study presents evidences on the antifungal effect of selected LAB strains and their end products. Studies are currently being undertaken to evaluate the effectiveness in preventing postharvest diseases on citrus fruits. PMID:20722936

Gerez, C L; Carbajo, M S; Rollán, G; Torres Leal, G; Font de Valdez, G

2010-08-01

66

Screening and characterization of novel bacteriocins from lactic acid bacteria.  

PubMed

Bacteriocins produced by lactic acid bacteria (LAB) are expected to be safe antimicrobial agents. While the best studied LAB bacteriocin, nisin A, is widely utilized as a food preservative, various novel ones are required to control undesirable bacteria more effectively. To discover novel bacteriocins at the early step of the screening process, we developed a rapid screening system that evaluates bacteriocins produced by newly isolated LAB based on their antibacterial spectra and molecular masses. By means of this system, various novel bacteriocins were identified, including a nisin variant, nisin Q, a two-peptide bacteriocin, lactococcin Q, a leaderless bacteriocin, lacticin Q, and a circular bacteriocin, lactocyclicin Q. Moreover, some LAB isolates were found to produce multiple bacteriocins. They were characterized as to their structures, mechanisms of action, and biosynthetic mechanisms. Novel LAB bacteriocins and their biosynthetic mechanisms are expected for applications such as food preservation and peptide engineering. PMID:23649268

Zendo, Takeshi

2013-05-07

67

Development of Mucosal Vaccines Based on Lactic Acid Bacteria  

NASA Astrophysics Data System (ADS)

Today, sufficient data are available to support the use of lactic acid bacteria (LAB), notably lactococci and lactobacilli, as delivery vehicles for the development of new mucosal vaccines. These non-pathogenic Gram-positive bacteria have been safely consumed by humans for centuries in fermented foods. They thus constitute an attractive alternative to the attenuated pathogens (most popular live vectors actually studied) which could recover their pathogenic potential and are thus not totally safe for use in humans. This chapter reviews the current research and advances in the use of LAB as live delivery vectors of proteins of interest for the development of new safe mucosal vaccines. The use of LAB as DNA vaccine vehicles to deliver DNA directly to antigen-presenting cells of the immune system is also discussed.

Bermúdez-Humarán, Luis G.; Innocentin, Silvia; Lefèvre, Francois; Chatel, Jean-Marc; Langella, Philippe

68

Characterization of anti-listerial lactic acid bacteria isolated from Thai fermented fish products  

Microsoft Academic Search

Thai fermented fish products were screened for lactic acid bacteria capable of inhibitingListeriasp. (Listeria innocua). Of 4150 assumed lactic acid bacteria colonies from MRS agar plates that were screened by an agar-overlay method 58 (1.4%) were positive. Forty four of these strains were further characterized and 43 strains were inhibitory againstListeria monocytogenes. The strains were inhibitory to other Gram-positive (lactic

A. Østergaard; P. K. B. Embarek; C. Wedell-Neergaard; H. H. Huss; L. Gram

1998-01-01

69

Safe and sustainable systems for food-grade fermentations by genetically modified lactic acid bacteria  

Microsoft Academic Search

The last decade has seen a great increase in innovative improvements of lactic acid bacteria used in industrial food fermentations. In order to allow the genetically modified lactic acid bacteria to reach the market place, their novel genetic combinations should be selected, stably maintained, and expressed using food-grade systems that are safe, stable, and sustainable. This paper aims to review

Willem M. de Vos

1999-01-01

70

Identification of Lactic Acid Bacteria Isolated from Tulum Cheese During Ripening Period  

Microsoft Academic Search

The fresh Tulum cheese was manufactured and then ripened at 10 ± 2°C for 3 months. Isolation and identification of lactic acid bacteria (LAB) was carried out during the ripening period of 90 days. Lactic acid bacteria were isolated from PCA, M17, and MRS agar. The strains isolated were identified using morphology, colony pigmentation, production of carbon dioxide from glucose,

Mustafa Gurses; Ahmet Erdogan

2006-01-01

71

Electron transport chains of lactic acid bacteria - walking on crutches is part of their lifestyle  

PubMed Central

A variety of lactic acid bacteria contain rudimentary electron transport chains that can be reconstituted by the addition of heme and menaquinone to the growth medium. These activated electron transport chains lead to higher biomass production and increased robustness, which is beneficial for industrial applications, but a major concern when dealing with pathogenic lactic acid bacteria.

Brooijmans, Rob; Hugenholtz, Jeroen

2009-01-01

72

Comparison of Lactic Acid Bacteria Fermentation with Acid Treatments for Chitosan Production from Shrimp Waste  

Microsoft Academic Search

The traditional procedure for chitosan production involves use of a strong acid (HCl) for demineralization of chitin. This study reports application of a mixed culture of lactic acid bacteria (Lactobacillus plantarum, Lactobacillus acidophilus, and Lactobacillus lactis) fermentation in demineralization of chitin for chitosan production from shrimp waste. Chitosan produced from shrimp waste with lactic acid bacteria fermentation at 30°C for

Sureerat Phuvasate; Yi-Cheng Su

2010-01-01

73

Inhibition of hydrogen fermentation of organic wastes by lactic acid bacteria  

Microsoft Academic Search

The effects of lactic acid bacteria (LAB) on hydrogen fermentation of organic waste were investigated. For this three hydrogen producing strains of Clostridium were cultured with two lactic acid bacteria, i.e. Lactobacillus paracasei and Enterococcus durans, which were isolated from the wastes generated in the bean curd manufacturing. The decrease or cessation of hydrogen production by Clostridium was caused by

Tatsuya Noike; Hiroo Takabatake; Osamu Mizuno; Mika Ohba

2002-01-01

74

Improving the Quality of Fermented Camel Sausage by Controlling Undesirable Microorganisms with Selected Lactic Acid Bacteria  

Microsoft Academic Search

Main objectives of the present work was to study the possibility of preserving ground camel meat by a biological procedure using lactic acid bacteria to encourage an extended shelf-life of fresh meat in hot areas. Lactic acid bacteria isolated from natural fermented foodstuffs were selected for their antimicrobial activity, and used in sausage making from camel meat. Fresh meat purchased

I. KALALOU; M. FAID; T. A. AHAMI

75

Lactic acid bacteria as functional starter cultures for the food fermentation industry  

Microsoft Academic Search

The production of fermented foods is based on the use of starter cultures, for instance lactic acid bacteria that initiate rapid acidification of the raw material. Recently, new starter cultures of lactic acid bacteria with an industrially important functionality are being developed. The latter can contribute to the microbial safety or offer one or more organoleptic, technological, nutritional, or health

Frédéric Leroy; Luc De Vuyst

2004-01-01

76

Surface Binding of Aflatoxin B1 by Lactic Acid Bacteria  

PubMed Central

Specific lactic acid bacterial strains remove toxins from liquid media by physical binding. The stability of the aflatoxin B1 complexes formed with 12 bacterial strains in both viable and nonviable (heat- or acid-treated) forms was assessed by repetitive aqueous extraction. By the fifth extraction, up to 71% of the total aflatoxin B1 remained bound. Nonviable bacteria retained the highest amount of aflatoxin B1. Lactobacillus rhamnosus strain GG (ATCC 53103) and L. rhamnosus strain LC-705 (DSM 7061) removed aflatoxin B1 from solution most efficiently and were selected for further study. The accessibility of bound aflatoxin B1 to an antibody in an indirect competitive inhibition enzyme-linked immunosorbent assay suggests that surface components of these bacteria are involved in binding. Further evidence is the recovery of around 90% of the bound aflatoxin from the bacteria by solvent extraction. Autoclaving and sonication did not release any detectable aflatoxin B1. Variation in temperature (4 to 37°C) and pH (2 to 10) did not have any significant effect on the amount of aflatoxin B1 released. Binding of aflatoxin B1 appears to be predominantly extracellular for viable and heat-treated bacteria. Acid treatment may permit intracellular binding. In all cases, binding is of a reversible nature, but the stability of the complexes formed depends on strain, treatment, and environmental conditions.

Haskard, Carolyn A.; El-Nezami, Hani S.; Kankaanpaa, Pasi E.; Salminen, Seppo; Ahokas, Jorma T.

2001-01-01

77

Optimization of Lactic Acid Production by Lactic Acid Bacteria Isolated from Some Traditional Fermented Food in Nigeria  

Microsoft Academic Search

Abstract: Seven species of Lactic Acid Bacteria (LAB) namely L. fermentum,L. casei,L. brevis, L delbrueckii, L. acidophilus,L. plantarumand Leuconostoc mesenteroides were isolated from ogi, burukutu and retted cassava (fufu). The isolates were screened,for quantitative production of lactic acid using normal MRS broth andmodifi ed MRS broth under varying conditions of growth such,as temperature and pH and influence of carbon and

I. a. Adesokan; B. b. Odetoyinbo; B. m. Okanlawon

78

Studying Denitrification by Aerobic Endospore-forming Bacteria in Soil  

Microsoft Academic Search

\\u000a As part of the aerobic endospore-forming bacteria in soil, members of the genus Bacillus sensu stricto and related species are involved in denitrification – one of the main processes in the global nitrogen cycle. So far, only\\u000a limited information on the denitrification abilities and the distribution of the key denitrification genes in these organisms\\u000a is available. This chapter provides a

Ines Verbaendert; Paul De Vos

79

Aerobic and Anaerobic Starvation Metabolism in Methanotrophic Bacteria  

PubMed Central

The capacity for anaerobic metabolism of endogenous and selected exogenous substrates in carbon- and energy-starved methanotrophic bacteria was examined. The methanotrophic isolate strain WP 12 survived extended starvation under anoxic conditions while metabolizing 10-fold less endogenous substrate than did parallel cultures starved under oxic conditions. During aerobic starvation, the cell biomass decreased by 25% and protein and lipids were the preferred endogenous substrates. Aerobic protein degradation (24% of total protein) took place almost exclusively during the initial 24 h of starvation. Metabolized carbon was recovered mainly as CO(inf2) during aerobic starvation. In contrast, cell biomass decreased by only 2.4% during anaerobic starvation, and metabolized carbon was recovered mainly as organic solutes in the starvation medium. During anaerobic starvation, only the concentration of intracellular low-molecular-weight compounds decreased, whereas no significant changes were measured for cellular protein, lipids, polysaccharides, and nucleic acids. Strain WP 12 was also capable of a limited anaerobic glucose metabolism in the absence of added electron acceptors. Small amounts of CO(inf2) and organic acids, including acetate, were produced from exogenous glucose under anoxic conditions. Addition of potential anaerobic electron acceptors (fumarate, nitrate, nitrite, or sulfate) to starved cultures of the methanotrophs Methylobacter albus BG8, Methylosinus trichosporium OB3b, and strain WP 12 did not stimulate anaerobic survival. However, anaerobic starvation of these bacteria generally resulted in better survival than did aerobic starvation. The results suggest that methanotrophic bacteria can enter a state of anaerobic dormancy accompanied by a severe attenuation of endogenous metabolism. In this state, maintenance requirements are presumably provided for by fermentation of certain endogenous substrates. In addition, low-level catabolism of exogenous substrates may support long-term anaerobic survival of some methanotrophic bacteria.

Roslev, P.; King, G. M.

1995-01-01

80

Method for quantification of aerobic anoxygenic phototrophic bacteria  

Microsoft Academic Search

Accurate quantification of aerobic anoxygenic phototrophic bacteria (AAPB) is of crucial importance for estimation of the\\u000a role of AAPB in the carbon cycling in marine ecosystems. The normally used method “epifluorescence microscope-infrared photography\\u000a (EFM-IRP)” is, however, subject to positive errors introduced by mistaking cyanobacteria as AAPB due to the visibility of\\u000a cyanobacteria under infrared photographic conditions for AAPB. This error

Yao Zhang; Nianzhi Jiao

2004-01-01

81

Metabolite Profiles of Lactic Acid Bacteria in Grass Silage?  

PubMed Central

The metabolite production of lactic acid bacteria (LAB) on silage was investigated. The aim was to compare the production of antifungal metabolites in silage with the production in liquid cultures previously studied in our laboratory. The following metabolites were found to be present at elevated concentrations in silos inoculated with LAB strains: 3-hydroxydecanoic acid, 2-hydroxy-4-methylpentanoic acid, benzoic acid, catechol, hydrocinnamic acid, salicylic acid, 3-phenyllactic acid, 4-hydroxybenzoic acid, (trans, trans)-3,4-dihydroxycyclohexane-1-carboxylic acid, p-hydrocoumaric acid, vanillic acid, azelaic acid, hydroferulic acid, p-coumaric acid, hydrocaffeic acid, ferulic acid, and caffeic acid. Among these metabolites, the antifungal compounds 3-phenyllactic acid and 3-hydroxydecanoic acid were previously isolated in our laboratory from liquid cultures of the same LAB strains by bioassay-guided fractionation. It was concluded that other metabolites, e.g., p-hydrocoumaric acid, hydroferulic acid, and p-coumaric acid, were released from the grass by the added LAB strains. The antifungal activities of the identified metabolites in 100 mM lactic acid were investigated. The MICs against Pichia anomala, Penicillium roqueforti, and Aspergillus fumigatus were determined, and 3-hydroxydecanoic acid showed the lowest MIC (0.1 mg ml?1 for two of the three test organisms).

Broberg, Anders; Jacobsson, Karin; Strom, Katrin; Schnurer, Johan

2007-01-01

82

Aerobic Respiration in the Gram-Positive Bacteria  

Microsoft Academic Search

The group of Gram-positive bacteria is a major phylum of prokaryotes, including several typical saprophytic aerobes. Their\\u000a respiratory chains are apparently similar to those of eukaryotic mitochondria, but in several points are different from them.\\u000a The respiratory chain of Gram-positives, like many bacteria, contains branched electron transfer pathways, usually 1-3 heme-Cu\\u000a oxidases, but SoxB-type cytochrome c oxidases (cytochrome b(a\\/o)3) are

Nobhuito Sone; Cecilia Hagerhall; Junshi Sakamoto

83

Biodegradation of Asphalt Cement-20 by Aerobic Bacteria  

PubMed Central

Seven gram-negative, aerobic bacteria were isolated from a mixed culture enriched for asphalt-degrading bacteria. The predominant genera of these isolates were Pseudomonas, Acinetobacter, Alcaligenes, Flavimonas, and Flavobacterium. The mixed culture preferentially degraded the saturate and naphthene aromatic fractions of asphalt cement-20. A residue remained on the surface which was resistant to biodegradation and protected the underlying asphalt from biodegradation. The most potent asphalt-degrading bacterium, Acinetobacter calcoaceticus NAV2, excretes an emulsifier which is capable of emulsifying the saturate and naphthene aromatic fractions of asphalt cement-20. This emulsifier is not denatured by phenol.

Pendrys, John P.

1989-01-01

84

Purification Techniques of Bacteriocins from Lactic Acid Bacteria and Other Gram-Positive Bacteria  

Microsoft Academic Search

\\u000a The search for new antimicrobial peptides produced by lactic acid ­bacteria and other Gram-positive microorganisms has become\\u000a an interesting field of research in the past decades. The fact that bacteriocins are active against numerous foodborne and\\u000a human pathogens, are produced by generally regarded as safe (GRAS) microorganisms, and are readily degraded by proteolytic\\u000a host systems makes them attractive candidates for

Lucila Saavedra; Fernando Sesma

2011-01-01

85

Reduction of patulin in aqueous solution by lactic acid bacteria.  

PubMed

This study aims to investigate the ability of lactic acid bacteria (LAB) to remove patulin (PAT) from aqueous solution with respect to the bacterial viability, initial PAT concentration, incubation time, temperature, and pH. The removal of PAT determined by high-performance liquid chromatography (HPLC) coupled with UV detector. The maximum PAT uptake was achieved by Bifidobacterium bifidum 6071 and Lactobacillus rhamnosus 6149 strains (52.9% and 51.1%) for viable and (54.1% and 52.0%) for nonviable cells after 24 h incubation. The highest removal of PAT was at pH 4.0 and 37 °C and increased with decreasing of toxin levels. The removal ability of selected strains could represent new strategies for a possible application in contaminated food products and animal feed. PMID:22394296

Hatab, Shaimaa; Yue, Tianli; Mohamad, Osama

2012-03-06

86

Antibiotic susceptibility of different lactic acid bacteria strains.  

PubMed

Five lactic acid bacteria (LAB) strains belonging to species Lactobacillus acidophilus, Lactobacillus helveticus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus delbrueckii subsp. lactis and Streptococcus thermophilus were tested for their susceptibility to 27 antibiotics. The minimum inhibitory concentrations of each antimicrobial were determined using a microdilution test. Among the strains a high susceptibility was detected for most of the cell-wall synthesis inhibitors (penicillins, cefoxitin and vancomycin) and resistance toward inhibitors of DNA synthesis (trimethoprim/sulfonamides and fluoroquinolones). Generally, the Lactobacillus strains were inhibited by antibiotics such as chloramphenicol, erythromycin and tetracycline at breakpoint levels lower or equal to the levels defined by the European Food Safety Authority. Despite the very similar profile of S. thermophilus LC201 to lactobacilli, the detection of resistance toward erythromycin necessitates the performance of additional tests in order to prove the absence of transferable resistance genes. PMID:22146692

Karapetkov, N; Georgieva, R; Rumyan, N; Karaivanova, E

2011-12-01

87

[Protection against Salmonella via immunization with recombinant lactic acid bacteria].  

PubMed

Mucosal immunization of hens may be effective to prevent contamination of Salmonella enterica serovar Enteritidis (SE) in eggs. Lactic acid bacteria have been considered potential vaccine delivery agents because they are safe, immunogenic, and inexpensive. Our research group has been investigating the development of oral vaccines against SE using a Lactobacillus casei strain as an antigen delivery vehicle. Recombinant lactobacilli expressing SE antigens FliC and SipC have been constructed and administered to mice. Antigen specific immune responses and protective immunity were elicited after the immunization. For adjuvant delivery, IL-1beta-secreting L. casei was also engineered and its efficacies were evaluated in vitro and in vivo. This article reviews a novel approach to develop SE vaccines using recombinant lactobacilli. PMID:22894061

Kajikawa, Akinobu

2012-08-01

88

Analysis of vaginal lactic acid producing bacteria in healthy women.  

PubMed

Vaginal lactic acid-producing bacteria of 80 pre-menopausal women were studied by isolation on Blood and DeMan-Rogosa-Sharpe agar, PCR with group-specific primers for Lactobacillus-denaturing gradient gel electrophoresis (DGGE), and PCR with specific primers for V3 region in 16S rRNA-temporal temperature gel electrophoresis (TTGE). Conventional isolation method on media detected only one lactobacillus (Lactobacillus brevis) while TTGE detected only Lactobacillus sp. DGGE detected seven Lactobacillus species; L. coleohominis, L. crispatus, L. iners, L. reuteri, L. rhamnosus, L. vaginalis, and Leuconostoc lactis. L. acidophilus and L. gasseri, which are prevalent in Western women, were not detected in Korean women. Furthermore, L. rhamnosus, Leuc. lactis, L. coleohominis, and Weissella cibaria, which were not previously reported in the vaginal microbiota of Korean women, were detected. The five most prevalent LABs in vaginal microbiota in Korean women were L. iners, Enterococcus faecalis, L. crispatus, Leuc. lactis, and W. cibaria. PMID:18176534

Nam, Hyeran; Whang, Kyunghee; Lee, Yeonhee

2007-12-01

89

Spray-drying of bacteriocin-producing lactic acid bacteria.  

PubMed

Cell survival, cellular damage, and antagonistic activity were investigated after spray-drying of four bacteriocin-producing strains of lactic acid bacteria: Lactococcus lactis subsp. lactis 140, isolated from natural whey culture and producing a narrow-inhibitory spectrum bacteriocin); L. lactis subsp. lactis G35, isolated from pizza dough and producing nisin; Lactobacillus curvatus 32Y and Lactobacillus sp. 8Z, isolated from dry sausages. Trials were performed with bacteria suspended in skimmed milk or directly grown in whey. Three air temperatures at the inlet of the drier (160, 180, and 200 degrees C) and three flow rates (10, 13, and 17 ml/min) were assayed. Cell viability and bacteriocin activity of the dried materials were determined immediately after the process and after 5, 15, 30, and 60 days of storage at 4 degrees C. There was no significant difference between the two feeding suspensions in cell survival, always decreasing with the increase of inlet-air temperature. No loss of bacteriocin activity was detected in reconstituted powders, nor was any loss of ability to produce bacteriocin found after drying. Investigations of sensitivity to NaCl revealed only temporary damage to dried bacteria. During storage for 2 months at 4 degrees C, all samples, but mainly the lactococcal strains, displayed a gradual decrease in cell survival. Bacteriocin activity remained at the same level, allowing powders to be considered as effective biopreservatives. PMID:10419271

Mauriello, G; Aponte, M; Andolfi, R; Moschetti, G; Villani, F

1999-07-01

90

Diversity of lactic acid bacteria of the bioethanol process  

PubMed Central

Background Bacteria may compete with yeast for nutrients during bioethanol production process, potentially causing economic losses. This is the first study aiming at the quantification and identification of Lactic Acid Bacteria (LAB) present in the bioethanol industrial processes in different distilleries of Brazil. Results A total of 489 LAB isolates were obtained from four distilleries in 2007 and 2008. The abundance of LAB in the fermentation tanks varied between 6.0 × 105 and 8.9 × 108 CFUs/mL. Crude sugar cane juice contained 7.4 × 107 to 6.0 × 108 LAB CFUs. Most of the LAB isolates belonged to the genus Lactobacillus according to rRNA operon enzyme restriction profiles. A variety of Lactobacillus species occurred throughout the bioethanol process, but the most frequently found species towards the end of the harvest season were L. fermentum and L. vini. The different rep-PCR patterns indicate the co-occurrence of distinct populations of the species L. fermentum and L. vini, suggesting a great intraspecific diversity. Representative isolates of both species had the ability to grow in medium containing up to 10% ethanol, suggesting selection of ethanol tolerant bacteria throughout the process. Conclusions This study served as a first survey of the LAB diversity in the bioethanol process in Brazil. The abundance and diversity of LAB suggest that they have a significant impact in the bioethanol process.

2010-01-01

91

Hydrolytic breakdown of lactoferricin by lactic acid bacteria.  

PubMed

Lactoferricin is a 25-amino acid antimicrobial peptide fragment that is liberated by pepsin digestion of lactoferrin present in bovine milk. Along with its antibacterial properties, lactoferricin has also been reported to have immunostimulatory, antiviral, and anticarcinogenic effects. These attributes provide lactoferricin and other natural bioactive peptides with the potential to be functional food ingredients that can be used by the food industry in a variety of applications. At present, commercial uses of these types of compounds are limited by the scarcity of information on their ability to survive food processing environments. We have monitored the degradation of lactoferricin during its incubation with two types of lactic acid bacteria used in the yogurt-making industry, Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus, with the aim of assessing the stability of this milk protein-derived peptide under simulated yogurt-making conditions. Analysis of the hydrolysis products isolated from these experiments indicates degradation of this peptide near neutral pH by lactic acid bacteria-associated peptidases, the extent of which was influenced by the bacterial strain used. However, the data also showed that compared to other milk-derived bioactive peptides that undergo complete degradation under these conditions, the 25-amino acid lactoferricin is apparently more resistant, with approximately 50% of the starting material remaining after 4 h of incubation. These findings imply that lactoferricin, as a natural milk protein-derived peptide, has potential applications in the commercial production of yogurt-like fermented dairy products as a multi-functional food ingredient. PMID:19924455

Paul, Moushumi; Somkuti, George A

2009-11-19

92

Lactic Acid Bacteria Convert Human Fibroblasts to Multipotent Cells  

PubMed Central

The human gastrointestinal tract is colonized by a vast community of symbionts and commensals. Lactic acid bacteria (LAB) form a group of related, low-GC-content, gram-positive bacteria that are considered to offer a number of probiotic benefits to general health. While the role of LAB in gastrointestinal microecology has been the subject of extensive study, little is known about how commensal prokaryotic organisms directly influence eukaryotic cells. Here, we demonstrate the generation of multipotential cells from adult human dermal fibroblast cells by incorporating LAB. LAB-incorporated cell clusters are similar to embryoid bodies derived from embryonic stem cells and can differentiate into endodermal, mesodermal, and ectodermal cells in vivo and in vitro. LAB-incorporated cell clusters express a set of genes associated with multipotency, and microarray analysis indicates a remarkable increase of NANOG, a multipotency marker, and a notable decrease in HOX gene expression in LAB-incorporated cells. During the cell culture, the LAB-incorporated cell clusters stop cell division and start to express early senescence markers without cell death. Thus, LAB-incorporated cell clusters have potentially wide-ranging implications for cell generation, reprogramming, and cell-based therapy.

Ohta, Kunimasa; Kawano, Rie; Ito, Naofumi

2012-01-01

93

Aerobic growth of campylobacter in media supplemented with a-ketoglutaric, lactic, and/or fumaric acids  

Technology Transfer Automated Retrieval System (TEKTRAN)

A study was conducted to examine the ability of Campylobacter spp. to grow aerobically in media supplemented with selected organic acids. Basal broth media composed of tryptose, yeast extract, and a mineral-vitamin solution was supplemented with a-ketoglutaric, lactic, and/or fumaric acids. The fina...

94

Glycerol metabolism and bitterness producing lactic acid bacteria in cidermaking.  

PubMed

Several lactic acid bacteria were isolated from bitter tasting ciders in which glycerol was partially removed. The degradation of glycerol via glycerol dehydratase pathway was found in 22 out of 67 isolates. The confirmation of glycerol degradation by this pathway was twofold: showing their glycerol dehydratase activity and detecting the presence of the corresponding gene by a PCR method. 1,3-propanediol (1,3-PDL) and 3-hydroxypropionic acid (3-HP) were the metabolic end-products of glycerol utilization, and the accumulation of the acrolein precursor 3-hydroxypropionaldehyde (3-HPA) was also detected in most of them. The strain identification by PCR-DGGE rpoB showed that Lactobacillus collinoides was the predominant species and only 2 belonged to Lactobacillus diolivorans. Environmental conditions conducting to 3-HPA accumulation in cidermaking were studied by varying the fructose concentration, pH and incubation temperature in L. collinoides 17. This strain failed to grow with glycerol as sole carbon source and the addition of fructose enhanced both growth and glycerol degradation. Regarding end-products of glycerol metabolism, 1,3-PDL was always the main end-product in all environmental conditions assayed, the only exception being the culture with 5.55 mM fructose, where equimolar amounts of 1,3-PDL and 3-HP were found. The 3-HPA was transitorily accumulated in the culture medium under almost all culture conditions, the degradation rate being notably slower at 15 degrees C. However, no disappearance of 3-HPA was found at pH 3.6, a usual value in cider making. After sugar exhaustion, L. collinoides 17 oxidated lactic acid and/or mannitol to obtain energy and these oxidations were accompanied by the removal of the toxic 3-HPA increasing the 1,3-PDL, 3-HP and acetic acid contents. PMID:18180066

Garai-Ibabe, G; Ibarburu, I; Berregi, I; Claisse, O; Lonvaud-Funel, A; Irastorza, A; Dueñas, M T

2007-11-12

95

Simultaneous saccharification and fermentation of furfural residues by mixed cultures of lactic acid bacteria and yeast to produce lactic acid and ethanol  

Microsoft Academic Search

In a cellulosic ethanol production system, yeasts cannot be reused, and it is difficult to avoid the formation of lactic acid.\\u000a A novel mixed fermentation system based on water-rinsed furfural residue was designed to produce lactic acid and ethanol simultaneously\\u000a by yeast and lactic acid bacteria. The fermentation broth can be used for the production of lactic acid, ethanol, or

Yong Tang; Danqing Zhao; Liwei Zhu; Jianxin Jiang

96

Biopreservative activity of lactic acid bacteria on suya produced from poultry meat  

Microsoft Academic Search

The influence of lactic acid bacteria (LAB) isolated from poultry meat on the attributes of suya was investigated. Lactobacillus plantarum with the highest frequency of occurrence (90%) produced the highest amount of lactic acid (16.2 g\\/l) and inhibited all the indicator organisms with the exception of Candida albicans and Proteus vulgaris. Consequently, L. plantarum was chosen as the starter culture

I. A. Adesokan; B. B. Odetoyinbo; A. O. Olubamiwa

97

Lactic Acid Bateria - Friend or Foe? Lactic Acid Bacteria in the Production of Polysaccharides and Fuel Ethanol  

Technology Transfer Automated Retrieval System (TEKTRAN)

Lactic acid bacteria (LAB) have been widely used in the production of fermented foods and as probiotics. Alternan is a glucan with a distinctive backbone structure of alternating alpha-(1,6) and alpha-(1,3) linkages produced by the LAB Leuconostoc mesenteroides. In recent years, improved strains f...

98

Metabolic engineering of lactic acid bacteria: overview of the approaches and results of pathway rerouting involved in food fermentations  

Microsoft Academic Search

Lactic acid bacteria such as Lactococcus lactis are the microorganisms of choice for performing metabolic engineering in relation to food fermentation. These bacteria are used extensively in food fermentations, they have a simple and therefore controllable metabolism and the molecular genetics of these food bacteria is well-developed. There have been recent successes in metabolic engineering in these lactic acid bacteria,

Jeroen Hugenholtz; Michiel Kleerebezem

1999-01-01

99

Genetically modified lactic acid bacteria: applications to food or health and risk assessment  

Microsoft Academic Search

Lactic acid bacteria have a long history of use in fermented food products. Progress in gene technology allows their modification by introducing new genes or by modifying their metabolic functions. These modifications may lead to improvements in food technology (bacteria better fitted to technological processes, leading to improved organoleptic properties…), or to new applications including bacteria producing therapeutic molecules that

Pierre Renault

2002-01-01

100

Thermotolerance of meat spoilage lactic acid bacteria and their inactivation in vacuum-packaged vienna sausages  

Microsoft Academic Search

Heat resistance of three meat spoilage lactic acid bacteria was determined in vitro. D-values at 57, 60 and 63 °C were 52.9, 39.3 and 32.5 s for Lactobacillus sake, 34.9, 31.3 and 20.2 s for Leuconostoc mesenteroides and 22.5, 15.6 and 14.4 s for Lactobacillus curvatus, respectively. The three lactic acid bacteria were heat sensitive, as one log reductions in

C. M. A. P. Franz; A. von Holy

1996-01-01

101

Evaluation of Cathra system for identifying gram negative aerobic bacteria.  

PubMed Central

The Cathra system is a commercial multipoint inoculation method for the identification of aerobic Gram negative bacteria. The system uses a replicator technique in which 21 different agar media can be inoculated simultaneously with 36 organisms. Identifications are made by use of a special computer database. The performance of this system was compared with that of the API 20E for the identification of 372 clinical isolates of Enterobacteriaceae and 133 miscellaneous Gram negative bacteria. For enterobacteria, the Cathra system was in 97% agreement with API 20E at species level and 98% at genus level. For miscellaneous Gram negative strains the two systems were in 59% agreement at species level and 77% at genus level. The Cathra system is suitable for use in diagnostic laboratories, especially those with a heavy workload and a wish to use break-point sensitivity testing. The identification database for miscellaneous Gram negative organisms, however, needs to be expanded.

Ling, J M; Zhang, L C; Hui, Y W; French, G L

1990-01-01

102

Oxygen tolerance of strictly aerobic hydrogen-oxidizing bacteria.  

PubMed

Growth of various bacteria, especially aerobic hydrogen-oxidizing bacteria, in the presence of 2 to 100% (v/v) oxygen in the gas atmosphere was evaluated. The bacterial strains included Alcaligenes eutrophus, A. paradoxus, Aquaspirillum autotrophicum, Arthrobacter spec. strain 11 X, Escherichia coli, Arthrobacter globiformis, Nocardia opaca, N. autotrophica, Paracoccus denitrificans, Pseudomonas facilis, P. putida, and Xanthobacter autotrophicus. Under heterotrophic conditions with fructose or gluconate as substrates neither colony formation on solid medium nor the growth rates in liquid media were drastically impaired by up to 100% oxygen. In contrast, autotrophic growth--with hydrogen, carbon dioxide and up to 80% oxygen in the gas atmosphere--was strongly depressed by high oxygen concentrations. However, only the growth rate, not the viability of the cells, was decreased. Growth retardation was accompanied by a decrease of hydrogenase activity. PMID:7049081

Wilde, E; Schlegel, H G

1982-05-01

103

Chemical Characterization of Wines Fermented with Various Malo-lactic Bacteria1  

PubMed Central

Six malo-lactic strains of lactic acid bacteria were isolated from California wines and identified as Lactobacillus delbrueckii, L. buchneri, L. brevis, Leuconostoc citrovorum, and two strains of Pediococcus cerevisiae. Malo-lactic fermentation was induced in separate lots of wine by inoculation of each lot with one of the strains of bacteria. Malo-lactic fermentation had occurred in each inoculated wine within 2 months. The resultant wines were subjected to chemical analysis, including gas chromatographic examination of concentrated extracts of the wines. Only a few differences in composition were found when the malo-lactic wines were compared one with another. The differences that were found were in volatile acidity and in concentrations of acetoin (plus diacetyl) and probably diethyl succinate.

Pilone, Gordon J.; Kunkee, Ralph E.; Webb, A. Dinsmoor

1966-01-01

104

Fermentation of aqueous plant seed extracts by lactic acid bacteria  

SciTech Connect

The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgaricus, L. acidophilus, and Streptococcus thermophilus. Organisms were inoculated individually into all of the seed extracts; L. bulgaricus and S. thermophilus were also evaluated together as inocula for fermenting the legume extracts. During fermentation, bacterial population and changes in titratable acidity, pH, viscosity, and color were measured over a 72 h period at 37 degrees C. Maximum bacterial populations, titratable acidity, pH, and viscosity varied depending upon the type of extract and bacterial strain. The maximum population of each organism was influenced by fermentable carbohydrates, which, in turn, influenced acid production and change in pH. Change in viscosity was correlated with the amount of protein and titratable acidity of products. Color was affected by pasteurization treatment and fermentation as well as the source of extract. In the extracts inoculated simultaneously with L. bulgaricus and S. thermophilus, a synergistic effect resulted in increased bacterial populations, titratable acidity, and viscosity, and decreased pH in all the legume extracts when compared to the extracts fermented with either of these organisms individually. Fermented extracts offer potential as substitutes for cultured dairy products. 24 references.

Schafner, D.W.; Beuchat, R.L.

1986-05-01

105

Removal of 3-methylindole by lactic acid bacteria in vitro  

PubMed Central

3-Methylindole (3MI) is a substance with an unpleasant odor that is found in intact male pigs and is known to negatively affect consumers of pork. The growth of four strains of lactic acid bacteria [Lactobacillus brevis 1.12 (L. brevis 1.12), L. plantarum 102, L. casei 6103 and L. plantarum ATCC8014] in incubation medium with 3MI was studied. The four strains were tested for their ability to remove 3MI from the medium. The growth of L. brevis 1.12 remained steady as the levels of 3MI increased 3MI from 0.2 to 1.0 ?g/ml. The 3MI removal ability of L. brevis 1.12 was the strongest among the four strains, and the highest removal rate was 65.35±0.3% in 1 ml incubation medium containing 1.0 ?g/ml 3MI for 120 h. Furthermore, the supernatant fluid of the fermentation broth of L. brevis 1.12 had a stronger ability to remove 3MI than cell pellets and cell extracts and the removal rate was 14.4±0.3% in 24 h. Further results indicate that the mode of removal of 3MI was not through the physical binding of cells by L. brevis 1.12.

MENG, XIAO; HE, ZHI-FEI; LI, HONG-JUN; ZHAO, XIN

2013-01-01

106

Antihepatocarcinoma activity of lactic acid bacteria fermented Panax notoginseng.  

PubMed

Panax notoginseng was used as the medium for lactic acid bacteria fermentation to manufacture product with antihepatocarcinoma activity. The fermentation broth prepared in a 250 mL Erlenmeyer flask was found to possess antiproliferation activity against hepatoma Hep3B cells. At the dosage of 500 microg/mL, the viability of hepatoma Hep3B cells was approximately 2.2%. When the fermentation was scaled up to a 6.6 L fermenter, it was found that the fermentation broth produced at 37 degrees C for 2 days showed the highest antihepatoma activity. Animal study revealed that when Hep3B implanted SCID mice were treated with 1000 mg/kg BW/day of the fermentation broth, tumor volume and tumor weight were reduced approximately 60% as compared to the negative control group. HPLC analyses showed that saponins in P. notoginseng including notoginsenoside R(1) and ginsenosides Rg(1), Rb(1), Rd, and Rh(4) decreased, but ginsenosides Rh(1) and Rg(3) increased during fermentation. LC-MS/MS revealed that the minor saponins ginsenoside F(1), protopanaxatriol, and notoginseng R(2) also exist in the fermentation product. It appears that ginsenoside Rg(3), ginsenoside Rh(1), and protopanaxatriol are possibly responsible for the enhanced antihepatocarcinoma activity of the P. notoginseng fermentation broth. PMID:20681639

Lin, Yu-Wei; Mou, Yu-Chen; Su, Chen-Chiang; Chiang, Been-Huang

2010-08-11

107

Characterisation of lactic acid bacteria isolated from fermented milk "laban".  

PubMed

The technological properties of 96 lactic acid bacteria isolated from Lebanese traditional fermented milk "laban" were characterised. They were classified by phenotypic and biochemical analyses as Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, thus indicating that laban is a fermented milk similar to yogurt. Most strains of L. bulgaricus (87.5%) exhibited a high acidification activity, whereas strains of streptococci showed low acidification ability. 33.3% of streptococci strains and 25% of lactobacilli strains displayed similar acidification performances as European strains. Results obtained for syneresis, texture and rheological parameters led us to consider that isolated strains were not low polymer-producing strains. Some of them displayed interesting characteristics such as low syneresis and high values for rheological parameters. The major flavour compounds found in pure cultures were acetaldehyde, acetone, 2-butanone, dimethyl disulfide, acetoin, 2,3-butanedione, 2,3-pentanedione, and acetic, hexanoic and butanoic acids. Acetaldehyde (7.4%) and organic acids (48.3%) were mainly produced by L. bulgaricus strains, whereas streptococci cultures contained high relative levels of 2,3-butanedione and acetoin, which represented around 82% of the total flavour compounds. Finally, strains isolated from laban samples exhibited different technological properties than those used in yogurt production, thus conferring specific characteristics to this product. PMID:16701913

Chammas, Gisele I; Saliba, Rachad; Corrieu, Georges; Béal, Catherine

2006-05-15

108

Heterologous production of bacteriocins by lactic acid bacteria.  

PubMed

Over the last two decades, bacteriocins produced by lactic acid bacteria (LAB) have been the subject of considerable research and industrial interest due to their potential as food biopreservatives. The development of heterologous expression systems for such antimicrobial compounds may offer a number of advantages over native systems, such as facilitating the control of bacteriocin gene expression or achieving higher production levels. In addition, the heterologous production by food-grade LAB offers an attractive method for overcoming some of the adverse situations that may affect the effectiveness of some bacteriocins in food systems. Construction of multibacteriocinogenic strains or acquisition of antimicrobial properties by industrial strains are further objectives that can be achieved through the use of heterologous gene expression systems. The development of new biotechnological tools and recent advances in LAB genetics account for the escalating number of studies dealing with heterologous production of bacteriocins by such hosts. This paper reviews the literature published on the subject and compares the different experimental strategies that have been used up to the present for this purpose. PMID:12381397

Rodríguez, J M; Martínez, M I; Horn, N; Dodd, H M

2003-01-25

109

Fermentation of Aqueous Plant Seed Extracts by Lactic Acid Bacteria  

PubMed Central

The effects of lactic acid bacterial fermentation on chemical and physical changes in aqueous extracts of cowpea (Vigna unguiculata), peanut (Arachis hypogea), soybean (Glycine max), and sorghum (Sorghum vulgare) were studied. The bacteria investigated were Lactobacillus helveticus, L. delbrueckii, L. casei, L. bulgaricus, L. acidophilus, and Streptococcus thermophilus. Organisms were inoculated individually into all of the seed extracts; L. bulgaricus and S. thermophilus were also evaluated together as inocula for fermenting the legume extracts. During fermentation, bacterial population and changes in titratable acidity, pH, viscosity, and color were measured over a 72-h period at 37°C. Maximum bacterial populations, titratable acidity, pH, and viscosity varied depending upon the type of extract and bacterial strain. The maximum population of each organism was influenced by fermentable carbohydrates, which, in turn, influenced acid production and change in pH. Change in viscosity was correlated with the amount of protein and titratable acidity of products. Color was affected by pasteurization treatment and fermentation as well as the source of extract. In the extracts inoculated simultaneously with L. bulgaricus and S. thermophilus, a synergistic effect resulted in increased bacterial populations, titratable acidity, and viscosity, and decreased pH in all the legume extracts when compared to the extracts fermented with either of these organisms individually. Fermented extracts offer potential as substitutes for cultured dairy products.

Schaffner, Donald W.; Beuchat, Larry R.

1986-01-01

110

Aerobic salivary bacteria in wild and captive Komodo dragons.  

PubMed

During the months of November 1996, August 1997, and March 1998, saliva and plasma samples were collected for isolation of aerobic bacteria from 26 wild and 13 captive Komodo dragons (Varanus komodoensis). Twenty-eight Gram-negative and 29 Gram-positive species of bacteria were isolated from the saliva of the 39 Komodo dragons. A greater number of wild than captive dragons were positive for both Gram-negative and Gram-positive bacteria. The average number of bacterial species within the saliva of wild dragons was 46% greater than for captive dragons. While Escherichia coli was the most common bacterium isolated from the saliva of wild dragons, this species was not present in captive dragons. The most common bacteria isolated from the saliva of captive dragons were Staphylococcus capitis and Staphylococcus capitis and Staphylococcus caseolyticus, neither of which were found in wild dragons. High mortality was seen among mice injected with saliva from wild dragons and the only bacterium isolated from the blood of dying mice was Pasteurella multocida. A competitive inhibition enzyme-linked immunosorbent assay revealed the presence of anti-Pasteurella antibody in the plasma of Komodo dragons. Four species of bacteria isolated from dragon saliva showed resistance to one or more of 16 antimicrobics tested. The wide variety of bacteria demonstrated in the saliva of the Komodo dragon in this study, at least one species of which was highly lethal in mice and 54 species of which are known pathogens, support the observation that wounds inflicted by this animal are often associated with sepsis and subsequent bacteremia in prey animals. PMID:12238371

Montgomery, Joel M; Gillespie, Don; Sastrawan, Putra; Fredeking, Terry M; Stewart, George L

2002-07-01

111

Lactic acid bacteria effective for regulating the growth of contaminant bacteria during the fermentation of Undaria pinnatifida (Phaeophyta)  

Microsoft Academic Search

Lactic acid fermentation of seaweed is a recent topic and quite limited information is available on culture conditions. To\\u000a know the suitable strains for use as a starter culture for seaweed fermentation, 14 lactic acid bacteria (LAB) strains, including\\u000a 11 species, were tested in culture conditions prepared with or without salt. A commercial product of Undaria pinnatifida powder was used

Motoharu Uchida; Masakazu Murata; Fumiyasu Ishikawa

2007-01-01

112

Hypolipidemic effects of lactic acid bacteria fermented cereal in rats  

PubMed Central

Background The objectives of the present study were to investigate the efficacy of the mixed culture of Lactobacillus acidophilus (DSM 20242), Bifidobacterium bifidum (DSM 20082) and Lactobacillus helveticus (CK60) in the fermentation of maize and the evaluation of the effect of the fermented meal on the lipid profile of rats. Methods Rats were randomly assigned to 3 groups and each group placed on a Diet A (high fat diet into which a maize meal fermented with a mixed culture of Lb acidophilus (DSM 20242), B bifidum (DSM 20082) and Lb helveticus (CK 60) was incorporated), B (unfermented high fat diet) or C (commercial rat chow) respectively after the first group of 7 rats randomly selected were sacrificed to obtain the baseline data. Thereafter 7 rats each from the experimental and control groups were sacrificed weekly for 4 weeks and the plasma, erythrocytes, lipoproteins and organs of the rats were assessed for cholesterol, triglyceride and phospholipids. Results Our results revealed that the mixed culture of Lb acidophilus (DSM 20242), B bifidum (DSM 20082) and Lb helveticus (CK 60) were able to grow and ferment maize meal into ‘ogi’ of acceptable flavour. In addition to plasma and hepatic hypercholesterolemia and hypertriglyceridemia, phospholipidosis in plasma, as well as cholesterogenesis, triglyceride constipation and phospholipidosis in extra-hepatic tissues characterized the consumption of unfermented hyperlipidemic diets. However, feeding the animals with the fermented maize diet reversed the dyslipidemia. Conclusion The findings of this study indicate that consumption of mixed culture lactic acid bacteria (Lb acidophilus (DSM 20242), Bifidobacterium bifidum (DSM 20082) and Lb helveticus (CK 60) fermented food results in the inhibition of fat absorption. It also inhibits the activity of HMG CoA reductase. This inhibition may be by feedback inhibition or repression of the transcription of the gene encoding the enzyme via activation of the sterol regulatory element binding protein (SREBP) transcription factor. It is also possible that consumption of fermented food enhances conversion of cholesterol to bile acids by activating cholesterol-7?-hydroxylase.

2012-01-01

113

Lack of inhibitory effects of Lactic acid bacteria on 1,2-dimethylhydrazine-induced colon tumors in rats  

Microsoft Academic Search

AIM: A myriad of healthful effects has been attributed to the probiotic lactic acid bacteria, perhaps the most controversial issue remains that of anticancer activity. This study was aimed at investigating the putative anti-cancer effects of lactic acid bacteria strains on the progression of colon tumor in 1,2-dimethylhydrazine (DMH)-treated animals. METHODS: The strain of lactic acid bacteria used in this

Wei Li; Chong-Bi Li

2003-01-01

114

Identification of lactic acid bacteria: culture-dependent and culture-independent methods  

Microsoft Academic Search

Because of their well-documented fermentative and claimed health-promoting properties, lactic acid bacteria (LAB) are one of the most important groups of bacteria to the food industry. The correct species identification of LAB is of paramount importance from the technological, ecological, and safety point of view. This paper provides an overview of phenotypic and genotypic techniques that are currently used for

Robin Temmerman; Geert Huys; Jean Swings

2004-01-01

115

Identification and succession of lactic acid bacteria during fermentation of 'urutan', a Balinese indigenous fermented sausage  

Microsoft Academic Search

'Urutan' is a Balinese traditional fermented sausage, which is made of lean pork and fat mixed with spices, sugar, and salt. The mixture is stuffed into cleaned pig intestine and fermented under uncontrolled condition during sun drying for 5 days. The investigation showed that lactic acid bacteria (LAB) were the dominating bacteria during 'urutan' fermentation. Among the 71 isolates obtained,

N. S. Antara; I. N. Sujaya; A. Yokota; K. Asano; W. R. Aryanta; F. Tomita

2002-01-01

116

Production of nitric oxide (NO) by lactic acid bacteria isolated from fermented products  

Microsoft Academic Search

In this study, the bacteria which were isolated from various milk and fermented food products were tested for their ability to convert metmyoglobin to nitrosomyoglobin. Lactic acid bacteria were isolated from samples of raw milk, unsalted butter, Beyaz cheese, yoghurt, pickles and silage. The nitric oxide (NO) forming abilities of 1534 isolates were tested using plates of de Man, Rogosa,

Arzu Kart Gündo?du; Aynur Gül Karahan; M. Lütfü Çakmakç

2006-01-01

117

The effect of dietary fatty acids on lactic acid bacteria associated with the epithelial mucosa and from faecalia of Arctic charr, Salvelinus alpinus (L.).  

PubMed

Arctic charr, Salvelinus alpinus (L.), held in fresh water, were fed four experimental diets containing different polyunsaturated fatty acids (PUFA). In addition, one group fed a diet containing only coconut oil as sole lipid source served as control. The population of aerobic heterotrophic bacteria associated with the epithelial mucosa and the faecalia was estimated using the dilution plate technique. Generally, the population level of adherent bacteria increased along the digestive tract (stomach, small intestine and large intestine). Adherent Gram-negative and Gram-positive bacteria seemed to be present at equal levels in all parts of the alimentary tract. Lactic acid bacteria dominated among the Gram-positive bacteria, and they were detected in all regions of fish fed the PUFA supplemented diets. The frequency of lactic acid bacteria was highest in the digestive tract of fish fed diets with added 7.0% linolenic acid (18:3 n-3) or 4% of a PUFA mix. A lower frequency of lactic acid bacteria was found in fish fed dietary linoleic acid (18:2 n-6), and they were absent or present in low numbers in fish fed the coconut oil diet. It is suggested that dietary fatty acids affect the attachment sites for the gastrointestinal microbiota, possibly by modifying the fatty acid composition of the intestine wall. Numerical taxonomy procedures showed that the lactic acid bacteria Carnobacterium spp. and a Carnobacterium piscicola-like strain were predominant, with smaller numbers of Lactobacillus plantarum, Streptococcus spp. and Leuconostoc mesenteroides present. Seven strains of Carnobacterium spp. were further identified on the basis of 16S rDNA sequence analysis, and all these strains were identified as Carnobacterium piscicola. PMID:9830121

Ringø, E; Bendiksen, H R; Gausen, S J; Sundsfjord, A; Olsen, R E

1998-11-01

118

Synthesis of the cancer preventive peptide lunasin by lactic acid bacteria during sourdough fermentation.  

PubMed

This study aimed to exploit the potential of sourdough lactic acid bacteria to release lunasin during fermentation of cereal and nonconventional flours. The peptidase activities of a large number of sourdough lactic acid bacteria were screened using synthetic substrates. Selected lactic acid bacteria were used as sourdough starters to ferment wholemeal wheat, soybean, barley, amaranth, and rye flours. Proteinase activity during fermentation was characterized by SDS-PAGE analysis of the water-soluble extracts. Albumins having molecular masses of 18 to 22 kDa, which included the size of lunasin precursors, were markedly affected by proteolysis of lactic acid bacteria. After fermentation, lunasin from the water-soluble extracts was quantified, purified, and identified through RP-HPLC and nano-LC-ESI-MS analyses. Compared to control doughs, the concentration of lunasin increased up to 2-4 times during fermentation. Lactobacillus curvatus SAL33 and Lactobacillus brevis AM7 synthesized the highest concentrations of lunasin in all the flours. Besides the presence of the entire lunasin sequence, fragments containing the immunoreactive epitope RGDDDDDDDDD were also found. This study shows that fermentation by lactic acid bacteria increased the concentration of lunasin to levels that would suggest new possibilities for the biological synthesis and for the formulation of functional foods. PMID:22098174

Rizzello, Carlo G; Nionelli, Luana; Coda, Rossana; Gobbetti, Marco

2011-11-18

119

Use of virginiamycin to control the growth of lactic acid bacteria during alcohol fermentation  

Microsoft Academic Search

  The antibiotic virginiamycin was investigated for its effects on growth and lactic acid production by seven strains of lactobacilli\\u000a during the alcoholic fermentation of wheat mash by yeast. The lowest concentration of virginiamycin tested (0.5?mg Lactrol\\u000a TMkg?1 mash), was effective against most of the lactic acid bacteria under study, but Lactobacillus plantarum was not significantly inhibited at this concentration. The

S H Hynes; D M Kjarsgaard; K C Thomas; W M Ingledew

1997-01-01

120

The role of transport processes in survival of lactic acid bacteria, Energy transduction and multidrug resistance  

Microsoft Academic Search

Lactic acid bacteria play an essential role in many food fermentation processes. They are anaerobic organisms which obtain their metabolic energy by substrate phosphorylation. In addition three secondary energy transducing processes can contribute to the generation of a proton motive force: proton\\/substrate symport as in lactic acid excretion, electrogenic precursor\\/product exchange as in malolactic and citrolactic fermentation and histidine\\/histamine exchange,

W. N. Konings; J. S. Lolkema; H. Bolhuis; H. W. van Veen; B. Poolman; A. J. M. Driessen

1997-01-01

121

Spoilage and safety characteristics of ground beef treated with lactic acid bacteria.  

PubMed

Lactic acid bacteria (LAB) can decrease numbers of Escherichia coli O157:H7 and Salmonella in ground beef during storage. Two dose-titration studies were conducted in ground beef to determine dose levels of LAB needed to inhibit the pathogens. A second study evaluated whether LAB masked changes typically associated with the spoilage of ground beef displayed under refrigerated (0 degrees C) or abusive (10 degrees C) temperatures packaged in both traditional overwrap (TOP) and modified atmosphere packaging (MAP; 80% O(2)-20% CO(2)). Microbial analyses were conducted to determine spoilage endpoints and pathogen reduction. In the dose-titration study, Salmonella was reduced by 3 log cycles at all doses (10(6), 10(7), and 10(8) LAB per g) after 3 days of storage and was eliminated after 5 days of storage. E. coli O157:H7 was reduced by 2 log cycles at all dosages after 3 days of storage and by 3 log cycles after 5 days of storage. In the spoilage studies, as expected, total aerobic plate counts and LAB populations in LAB-inoculated samples were higher than the controls initially, but the counts were similar near the end of the study. While total spoilage bacteria generally increased over time, very few differences existed between treatments stored at 0 degrees C and 10 degrees C in coliforms, Brochothrix thermosphacta, yeasts and molds, and Pseudomonas spp. counts for both the TOP and MAP samples. We conclude that LAB could potentially be added to ground beef in TOP and MAP as a processing intervention for E. coli O157:H7 and Salmonella without masking microbial spoilage characteristics. PMID:19903389

Hoyle, A R; Brooks, J C; Thompson, L D; Palmore, W; Stephens, T P; Brashears, M M

2009-11-01

122

Phylogenomic reconstruction of lactic acid bacteria: an update  

PubMed Central

Background Lactic acid bacteria (LAB) are important in the food industry for the production of fermented food products and in human health as commensals in the gut. However, the phylogenetic relationships among LAB species remain under intensive debate owing to disagreements among different data sets. Results We performed a phylogenetic analysis of LAB species based on 232 genes from 28 LAB genome sequences. Regardless of the tree-building methods used, combined analyses yielded an identical, well-resolved tree topology with strong supports for all nodes. The LAB species examined were divided into two groups. Group 1 included families Enterococcaceae and Streptococcaceae. Group 2 included families Lactobacillaceae and Leuconostocaceae. Within Group 2, the LAB species were divided into two clades. One clade comprised of the acidophilus complex of genus Lactobacillus and two other species, Lb. sakei and Lb. casei. In the acidophilus complex, Lb. delbrueckii separated first, while Lb. acidophilus/Lb. helveticus and Lb. gasseri/Lb. johnsonii were clustered into a sister group. The other clade within Group 2 consisted of the salivarius subgroup, including five species, Lb. salivarius, Lb. plantarum, Lb. brevis, Lb. reuteri, Lb. fermentum, and the genera Pediococcus, Oenococcus, and Leuconostoc. In this clade, Lb. salivarius was positioned most basally, followed by two clusters, one corresponding to Lb. plantarum/Lb. brevis pair and Pediococcus, and the other including Oenococcus/Leuconostoc pair and Lb. reuteri/Lb. fermentum pair. In addition, phylogenetic utility of the 232 genes was analyzed to identify those that may be more useful than others. The genes identified as useful were related to translation and ribosomal structure and biogenesis (TRSB), and a three-gene set comprising genes encoding ultra-violet resistance protein B (uvrB), DNA polymerase III (polC) and penicillin binding protein 2B (pbpB). Conclusions Our phylogenomic analyses provide important insights into the evolution and diversification of LAB species, and also revealed the phylogenetic utility of several genes. We infer that the occurrence of multiple, independent adaptation events in LAB species, have resulted in their occupation of various habitats. Further analyses of more genes from additional, representative LAB species are needed to reveal the molecular mechanisms underlying adaptation of LAB species to various environmental niches.

2011-01-01

123

Antibacterial activity of lactic acid bacteria against spoilage and pathogenic bacteria isolated from the same meat small-scale facility  

Microsoft Academic Search

A total of 87 lactic acid bacteria (LAB) (36 Lactobacillus sakei, 22 Enterococcus faecium, 16 Lactococcus garvieae, 11 Vagococcus carniphilus and 2 Enterococcus sp.) isolated from a small-scale facility producing traditional dry sausages were screened for antagonistic activity against other LAB and some spoilage and pathogenic microorganisms, also isolated from the same processing facility, except Listeria innocua (in lieu of

Salim Ammor; Grégoire Tauveron; Eric Dufour; Isabelle Chevallier

2006-01-01

124

Antibacterial activity of lactic acid bacteria against spoilage and pathogenic bacteria isolated from the same meat small-scale facility  

Microsoft Academic Search

The survival of Listeria innocua ATCC 33090, Staphylococcus aureus E1S-5 and\\/or Hafnia alvei E1E-25 in dual species biofilms with bacteriocin-like producing lactic acid bacteria (5 Vagococcus carniphilus, 3 Enterococcus faecium, 1 Lactobacillus sakei and 1 Enterococcus sp.) was investigated. The aim was to select strains able to repress the growth of undesirable bacteria in biofilms, i.e., the real mode of

Salim Ammor; Grégoire Tauveron; Eric Dufour; Isabelle Chevallier

2006-01-01

125

Improved stability of aerobic granules by selecting slow-growing nitrifying bacteria  

Microsoft Academic Search

This study investigated the feasibility of improving the stability of aerobic granules through selecting slow-growing nitrifying bacteria. For this purpose, four sequencing batch reactors were operated at different substrate N\\/COD ratios ranging from 5\\/100 to 30\\/100. Results showed that aerobic granules formed in all four reactors, and aerobic granulation was a gradual process evolving from the dispersed seed sludge to

Yu Liu; Shu-Fang Yang; Joo-Hwa Tay

2004-01-01

126

Factors influencing the production of volatile phenols by wine lactic acid bacteria.  

PubMed

This work aimed to evaluate the effect of certain factors on the production of volatile phenols from the metabolism of p-coumaric acid by lactic acid bacteria (LAB) (Lactobacillus plantarum, L. collinoides and Pediococcus pentosaceus). The studied factors were: pH, L-malic acid concentration, glucose and fructose concentrations and aerobic/anaerobic conditions. It was found that, in the pH range of 3.5 to 4.5, the higher the pH the greater the production of volatile phenols. This behaviour is correlated with the effect of pH on bacterial growth. Increasing levels of L-malic acid in the medium diminished the production of 4-vinylphenol (4VP) and stimulated the production of 4-ethylphenol (4EP) by L. plantarum NCFB 1752 and L. collinoides ESB 99. The conversion of 4VP into 4EP by the activity of the vinylphenol reductase may be advantageous to the cells in the presence of L-malic acid, presumably due to the generation of NAD+, a cofactor required by the malolactic enzyme. Relatively high levels of glucose (20 g/L) led to an almost exclusive production of 4VP by L. plantarum NCFB 1752, while at low concentrations (? 5 g/L), 4EP is mainly or solely produced. Part of the glucose may be diverted to the production of mannitol as an alternative pathway to regenerate NAD+. This is corroborated by the experiments done with fructose, a compound that can be used as an electron acceptor by some bacteria becoming reduced to mannitol. In anaerobiosis, the reduction of 4VP into 4EP is clearly favoured, which is consistent with the need to increase the availability of NAD+ in these conditions. This study shows that the amount and the ratio 4VP/4EP produced by LAB are greatly affected by certain environmental and medium composition factors. The behaviour of the bacteria seems to be driven by the intracellular NAD+/NADH balance. PMID:21329996

Silva, Isa; Campos, Francisco M; Hogg, Tim; Couto, José António

2011-02-02

127

Phenotypic and Genotypic Characterization of Lactic Acid Bacteria Isolated from Some Nigerian Traditional Fermented Foods  

Microsoft Academic Search

A total of 104 lactic acid bacteria were isolated from ogi, wara, fermenting cassava mash for local food product gari and raw milk for nono. They were characterized phenotypically and divided into six main groups, which are facultative heterofermentative rods, obligate heterofermentative rods, tetrad-forming homofermentative cocci, homofermentative cocci, heterofermentative cocci, and an unidentified group. A total of 40 strains with

Kolawole Banwo; Abiodun Sanni; Huarong Tan; Yuqing Tian

2012-01-01

128

Redirection of Pyruvate Pathway of Lactic Acid Bacteria to Improve Cheese Quality  

Microsoft Academic Search

Metabolic engineering in Lactic acid bacteria (LAB) has focused on changing of pyruvate metabolism to increase production of desired flavor compounds. A constructed mutant strain should contain no foreign DNA and antibiotic resistance genes. Therefore, food grade lactate dehydrogenase (ldh ) and diacetyl reductase (dar ) mutant strains were created using two plasmid system in this study. Metabolic end products

Ismail Akyol; Kalbiye Serdaroglu; Yekta Gezginc; K. Sinan Dayisoylu; M. Sait Ekinci; Emin Ozkose

2009-01-01

129

Effects of cultivation conditions on folate production by lactic acid bacteria  

Microsoft Academic Search

A variety of lactic acid bacteria were screened for their ability to produce folate intracellularly and\\/or extracellularly. Lactococcus lactis, Streptococcus thermophilus, and Leuconostoc spp. all produced folate, while most Lactobacillus spp., with the exception of Lactobacillus plantarum, were not able to produce folate. Folate production was further investigated in L. lactis as a model organism for metabolic engineering and in

Wilbert Sybesma; Marjo Starrenburg; Linda Tijsseling; Marcel H. N. Hoefnagel; Jeroen Hugenholtz

2003-01-01

130

Detoxification of patulin and ochratoxin A, two abundant mycotoxins, by lactic acid bacteria  

Microsoft Academic Search

Aim of the present study was to investigate the detoxification of two abundant mycotoxins, namely ochratoxin A (OTA) and patulin (PAT) which are frequently found in human foods, by lactic acid bacteria. The removal of the two mycotoxins from liquid medium by thirty different LAB strains was analyzed in a screening trial by the use of HPLC coupled with UV-

S. Fuchs; G. Sontag; R. Stidl; V. Ehrlich; M. Kundi; S. Knasmüller

2008-01-01

131

Occurrence of biogenic amine-forming lactic acid bacteria in wine and cider  

Microsoft Academic Search

A collection of 810 lactic acid bacteria (LAB) strains isolated from wine and cider was screened for potential biogenic amine (BA) producers by combining molecular and phenotypic approaches. A newly developed multiplex PCR method allowed for the simultaneous detection of four genes involved in the production of histamine (histidine decarboxylase, hdc), tyramine (tyrosine decarboxylase, tyrdc) and putrescine (via either ornithine decarboxylase,

M. Coton; A. Romano; G. Spano; K. Ziegler; C. Vetrana; C. Desmarais; A. Lonvaud-Funel; P. Lucas; E. Coton

2010-01-01

132

Competitive Selection of Lactic Acid Bacteria That Persist in the Human Oral Cavity ? †  

PubMed Central

Lactic acid bacteria (LAB) might offer opportunities as oral probiotics provided candidate strains persist in the mouth. After intake of a mixture of 69 LAB, strains of Lactobacillus fermentum and Lactobacillus salivarius were especially recovered. Coaggregation with other microbes is likely not a prerequisite for persistence since L. salivarius strongly coaggregated with typical oral cavity isolates, whereas L. fermentum failed to display this phenotype.

Snel, Johannes; Marco, Maria L.; Kingma, Fedde; Noordman, Wouter M.; Rademaker, Jan; Kleerebezem, Michiel

2011-01-01

133

Lactic acid bacteria – Potential for control of mould growth and mycotoxins: A review  

Microsoft Academic Search

Most data dealing with the biopreservative activity of lactic acid bacteria (LAB) are focused on their antibacterial effects. Food spoilage by mould and the occurrence of their mycotoxins constitute a potential health hazard. Development of biological control should help improve the safety of products by controlling mycotoxin contamination. Data have actually shown that many LAB can inhibit mould growth and

D. K. D. Dalié; A. M. Deschamps; F. Richard-Forget

2010-01-01

134

Enhancing stability of lactic acid bacteria and probiotics by Williopsis saturnus var. saturnus in fermented milks  

Microsoft Academic Search

Purpose – There is a need to improve stability of lactic acid bacteria (LAB) and probiotics in fermented milks especially at elevated temperatures. The purpose of this paper is to evaluate the impact of yeast Williopsis saturnus var. saturnus on stability of LAB and probiotic Lactobacillus rhamnosus in fermented milks. Design\\/methodology\\/approach – Fermented milks were made from reconstituted whole milk

Shao-Quan Liu; Marlene Tsao

2010-01-01

135

Growth of lactic acid bacteria and Rhizopus oligosporus during barley tempeh fermentation  

Microsoft Academic Search

The zygomycete Rhizopus oligosporus is traditionally used to ferment soybean tempeh, but it is also possible to ferment other legumes and cereals to tempeh. The traditional soybean tempeh harbours a multitude of microorganisms with potentially beneficial or detrimental effects on quality. Lactic acid bacteria (LAB) have positive effects on the safety of soybean tempeh, but the effects of LAB on

Xin Mei Feng; Anders R. B. Eriksson; Johan Schnürer

2005-01-01

136

Characterization of Proteolytic Effect of Lactic Acid Bacteria Starter Cultures on Thai Fermented Sausages  

Microsoft Academic Search

The objective of this study was to investigate the effect of starter culture addition on proteolysis of Thai fermented sausages. Sausages inoculated with six different external starter cultures—Pediococcus pentosaceous, Pediococcus acidilactici, Weissella cibaria, Lactobacillus plantarum, Lactobacillus pentosus, and Lactobacillus sakei—were compared with naturally fermented sausages. The results of microbiological analysis indicated that the dominance of lactic acid bacteria (LAB) could

Wiramsri Sriphochanart; Wanwisa Skolpap

2010-01-01

137

Interactions between Staphylococcus aureus and lactic acid bacteria: An old story with new perspectives  

Microsoft Academic Search

Staphylococcus aureus is a Gram positive opportunistic pathogen and a major concern for both animal and human health worldwide. In some contexts where Lactic Acid Bacteria (LAB) are the normal dominant microbiota, such as in fermented food or in the vaginal ecosystem, S. aureus sometimes colonises, persists, expresses virulence factors and produces food poisoning or urogenital infections, respectively. Studies on

C. Charlier; M. Cretenet; S. Even; Y. Le Loir

2009-01-01

138

Use of Human Lysozyme Transgenic Goat Milk in Cheese Making: Effects on Lactic Acid Bacteria Performance  

Microsoft Academic Search

Geneticallyengineeredgoatsexpressingelevatedlev- els of the antimicrobial enzyme lysozyme in their milk were developed to improve udder health, product shelf life, and consumer well-being. Thepurpose of this study was to evaluate the effect of lysozyme on the develop- ment of lactic acid bacteria (LAB) throughout the cheese-making process. Raw and pasteurized milk from 7 lysozyme transgenic goats and 7 breed-, age-, and

E. C. Scharfen; D. A. Mills; E. A. Maga

2007-01-01

139

Antibiotic Resistances of Starter and Probiotic Strains of Lactic Acid Bacteria  

Microsoft Academic Search

The antibiotic resistances of 45 lactic acid bacteria strains belonging to the genera Lactobacillus, Strepto- coccus, Lactococcus, Pediococcus, and Leuconostoc were investigated. The objective was to determine antibiotic resistances and to verify these at the genetic level, as is currently suggested by the European \\

Anja S. Hummel; Christian Hertel; Wilhelm H. Holzapfel; Charles M. A. P. Franz

2007-01-01

140

Effect of process parameters on the production of lactic acid bacteria in batch fermentation  

Microsoft Academic Search

The effect of aeration and type of neutralising agent on the growth of lactic acid bacteria, isolated from a typical Italian cheese, was investigated in laboratory fermenters, with the aim of defining process conditions for the production of autochthonous cul- tures to be used as starters in traditional cheese-making. Batch fermentation trials were carried out using six different bacterial species

Emanuele ZANNINI; Sara SANTARELLI; Andrea OSIMANI; Luana DELL' AQUILA; Francesca CLEMENTI

141

SCREENING AND IDENTIFICATION OF LACTIC ACID BACTERIA PRODUCING ANTIMICROBIAL COMPOUNDS FROM PIG GASTROINTESTINAL TRACTS  

Microsoft Academic Search

A total of 87 lactic acid bacteria were isolated from 15 samples of pig gastrointestinal tract. Antimicrobial activities of all isolates grown under oxygen-restricted conditions to eliminate the effect of hydrogen peroxide were tested against 5 pathogenic bacterial strains using agar well diffusion technique. Seventeen isolates exhibited antimicrobial activity against at least one indicator strain tested. Among the 17 isolates,

Nongpanga Khunajakr; Aporn Wongwicharn; Duangtip Moonmangmee; Sukon Tantipaiboonvut

2008-01-01

142

Comparative genomics of enzymes in flavor-forming pathways from amino acids in lactic acid bacteria  

Microsoft Academic Search

Lactic acid bacteria (LAB) have been widely used as starter or nonstarter cultures in the dairy industry for over a thousand years. They play an essential role in flavor formation during the fermentation of dairy products. Several metabolic routes can lead to the formation of flavor compounds when LAB are growing in milk. One of the main precursors for flavor

Mengjin Liu; Arjen Nauta; Christof Francke; Roland J. Siezen

2008-01-01

143

Screening of biogenic amine production by lactic acid bacteria isolated from grape must and wine  

Microsoft Academic Search

The potential to produce the biogenic amines tyramine, histamine and putrescine, was investigated for lactic acid bacteria (LAB) of various origin, including commercial malolactic starter cultures, type strains and 78 strains isolated from Spanish grape must and wine. The presence of biogenic amines in a decarboxylase synthetic broth was determined by reverse-phase high performance liquid chromatography (RP-HPLC). Tyramine was the

M. Victoria Moreno-Arribas; M. Carmen Polo; Felisa Jorganes; Rosario Muñoz

2003-01-01

144

Arginine, citrulline and ornithine metabolism by lactic acid bacteria from wine  

Microsoft Academic Search

The catabolism of arginine, an amino acid found in grape juice and wine, citrulline and ornithine was investigated in four lactic acid bacteria. Only Lactobacillus hilgardii X1B catabolized arginine and excreted citrulline into the medium. The recovery of arginine as ornithine was lower than the expected theoretical value. The arginase-urease pathway was not detected indicating that the amino acid degradation

M. E. Arena; F. M. Saguir; M. C. Manca de Nadra

1999-01-01

145

Identification of lactic acid bacteria isolated from traditional Sudanese fermented camel's milk (Gariss)  

Microsoft Academic Search

From 12 samples of gariss, a Sudanese traditionally fermented camel' s milk, 24 lactic acid bacteria were isolated and phenotypically characterized by biochemical tests and their ability to ferment different carbohydrates. Analysis of the observed data resulted in classifying the isolates into 11 groups, each group containing one or more isolates, 2 major groups were identified, the larger one composed

Ayman Ashmaig; Alaa Hasan; Eisa El Gaali

2009-01-01

146

Evolution and identification of lactic acid bacteria isolated during the ripening of Sardinian sausages  

Microsoft Academic Search

Lactic acid bacteria (LAB) were isolated during the production and the ripening of Sardinian sausage, a typical Italian dry fermented sausage. Samples were taken at different stages, and 112 strains were isolated. The isolates were characterized using the micromethod proposed by Font de Valdez et al. [Font de Valdez, G., Savoy de Giori, G., Oliver, G., & De Ruiz Holgado,

M. Greco; R. Mazzette; E. P. L. De Santis; A. Corona; A. M. Cosseddu

2005-01-01

147

EFFECTS OF DOSING WITH LACTIC ACID BACTERIA ON CRYPTOSPORIDIUM PARVUM INFECTION IN CALVES  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cryptosporidium parvum is a protozoan parasite that is a major cause of diarrheal illness in both humans and neonatal calves. Previous studies in humans and mice have suggested that use of probiotics in the form of lactic acid bacteria may be of benefit in reducing infection with C. parvum. Groups...

148

Preliminary characterization of bacteriocin-like substances from lactic acid bacteria isolated from organic leafy vegetables  

Microsoft Academic Search

This study presents the characterization of new strains of lactic acid bacteria (LAB) from organic vegetables. Forty-five strains of LAB isolated from vegetables were investigated by its antimicrobial activity against taxonomically related microorganisms. Genetic identification of selected LAB was performed by means of PCR method. These strains were Enterococcus faecium, Lactococcus lactis, Enterococcus hirae and Enterococcus canis. Bacteriocin-like substances were

A. G. Ponce; M. R. Moreira; C. E. del Valle; S. I. Roura

2008-01-01

149

Glucansucrases from lactic acid bacteria which produce water-insoluble polysaccharides from sucrose  

Technology Transfer Automated Retrieval System (TEKTRAN)

Dextrans and related glucans produced from sucrose by lactic acid bacteria have been studied for many years and are used in numerous commercial applications and products. Most of these glucans are water-soluble, except for a few notable exceptions from cariogenic Streptococcus spp. and a very small ...

150

The cell membrane and the struggle for life of lactic acid bacteria  

Microsoft Academic Search

The major life-threatening event for lactic acid bacteria (LAB) in their natural environment is the depletion of their energy sources and LAB can survive such conditions only for a short period of time. During periods of starvation LAB can exploit optimally the potential energy sources in their environment usually by applying proton motive force generating membrane transport systems. These systems

Wil. N. Konings

2002-01-01

151

Comparison of phenotypic and molecular tests to identify lactic acid bacteria  

PubMed Central

Twenty-nine lactic acid bacteria (LAB) isolates were submitted for identification using Biolog, API50CHL, 16S rDNA sequencing, and species-specific PCR reactions. The identification results were compared, and it was concluded that a polyphasic approach is necessary for proper LAB identification, being the molecular analyzes the most reliable.

Moraes, Paula Mendonca; Perin, Luana Martins; Junior, Abelardo Silva; Nero, Luis Augusto

2013-01-01

152

Strategies to improve the bacteriocin protection provided by lactic acid bacteria.  

PubMed

Lactic acid bacteria (LAB) produce a wide variety of antimicrobial peptides (bacteriocins) which contribute to the safety and preservation of fermented foods. This review discusses strategies that have been or could be employed to further enhance the commercial application of bacteriocins and/or bacteriocin-producing LAB for food use. PMID:23337424

O' Shea, Eileen F; Cotter, Paul D; Ross, R Paul; Hill, Colin

2013-01-18

153

Practical implications of lactate and pyruvate metabolism by lactic acid bacteria in food and beverage fermentations  

Microsoft Academic Search

This article reviews the metabolism of pyruvate and lactate by lactic acid bacteria (LAB) involved in food and beverage fermentations with an emphasis on practical implications. First, the formation of pyruvate and lactate from a range of substrates, including carbohydrates, organic acids and amino acids, is briefly described. The catabolism of pyruvate and lactate by LAB is then reviewed. This

S.-Q. Liu

2003-01-01

154

The role of interaction between yeasts and lactic acid bacteria in African fermented milks: a review  

Microsoft Academic Search

Yeasts are present in indigenous African fermented milks in numbers up to log 8 cfu g?1, together with a varied lactic acid bacteria (LAB) flora, and therefore potentially contribute to product characteristics. However, interaction between yeasts and LAB in these products has received little notice.In studies of indigenous fermented milk in Zimbabwe and Uganda, many samples contained more than one

Judith A. Narvhus; Tendekayi Henry Gadaga

2003-01-01

155

Cell membrane damage induced by phenolic acids on wine lactic acid bacteria  

Microsoft Academic Search

The aim of this work was to investigate the effect of phenolic acids on cell membrane permeability of lactic acid bacteria from wine. Several phenolic acids were tested for their effects on the cell membrane of Oenococcus oeni and Lactobacillus hilgardii by measuring potassium and phosphate efflux, proton influx and by assessing culture viability employing a fluorescence technique based on

F. M. Campos; J. A. Couto; A. R. Figueiredo; I. V. Tóth; A. O. S. S. Rangel; T. A. Hogg

2009-01-01

156

Potential of lactic acid bacteria isolated from specific natural niches in food production and preservation  

Microsoft Academic Search

Autochthonous strains of lactic acid bacteria (LAB) have been isolated from traditionally homemade cheeses collected from specific ecological localities across Serbia and Montenegro. Genetic and biochemical analysis of this LAB revealed that they produce bacteriocins, proteinases and exopolysaccharides. LAB produces a variety of antimicrobial substances with potential importance for food fermentation and preservation. Apart from the metabolic end products, some

Ljubisa Topisirovic; Milan Kojic; Djordje Fira; Natasa Golic; Ivana Strahinic; Jelena Lozo

2006-01-01

157

Class IIa bacteriocins from lactic acid bacteria: Antibacterial activity and food preservation  

Microsoft Academic Search

In the last decade, a variety of ribosomally synthesized antimicrobial peptides, or bacteriocins, produced by lactic acid bacteria have been identified and characterized. As a result of these studies, insight has been gained into various fundamental aspects of biology and biochemistry such as bacteriocin processing and secretion, mechanisms of cell immunity, and structure-function relationships. In parallel, there has been a

Saïd Ennahar; Kenji Sonomoto; Ayaaki Ishizaki

1999-01-01

158

Survival of probiotic bacteria during lactic acid fermentation of vegetable juices  

Microsoft Academic Search

The general objective of this research was to perform the lactic acid fermentative processes using different probiotic bacteria species unspecific to epiphytic microbiota of vegetables, with a view to achieve new knowledge concerning the possibility of developing and preservation their viability in vegetable juices. The carrots and the red beet were evaluated as potential substrat for the production of probiotic

Carmen Leane Nicolescu; Daniela Avram; Magda Gabriela; Bratu Iuliana Manea

159

FUNCTIONAL EXPRESSION OF BACTERIAL ZYMOBACTER PALMAE PYRUVATE DECARBOXYLASE GENE IN LACTIC ACID BACTERIA  

Technology Transfer Automated Retrieval System (TEKTRAN)

In this study, a pyruvate decarboxylase (PDC) gene from bacterial Zymobacter palmae (Zymopdc) was cloned, characterized, and introduced into lactic acid bacteria (LAB) via a shuttle vector pAK80 as part of a research strategy to develop an efficient ethanol producing LAB. Six constructs containing ...

160

Can Immunoregulatory Lactic Acid Bacteria Be Used as Dietary Supplements to Limit Allergies?  

Microsoft Academic Search

Studies in gnotobiotic animals have suggested that the intestinal bacterial flora may play an important role in priming the immune system during ontogeny to limit dysfunctional responses, including allergy. Prospective clinical studies have identified a higher incidence of allergy expression in early childhood among children who have low enteric populations of lactic acid bacteria (LAB), such as lactobacilli and bifidobacteria,

M. L. Cross; H. S. Gill

2001-01-01

161

The characterisation of lactic acid bacteria during the fermentation of an artisan Serbian sausage (Petrovská Klobása)  

Microsoft Academic Search

Petrovská Klobása is an artisan Serbian sausage made only from meat and spices without any additives or starter cultures. In order to characterise lactic acid bacteria (LAB) microflora, a total number of 404 LAB strains were isolated from 15 samples collected during 90days of the fermentation and 120days of storage of one batch of Petrovská Klobása. The isolates were preliminarily

Bojana Danilovi?; Nataša Jokovi?; Ljiljana Petrovi?; Katarina Veljovi?; Maja Tolina?ki; D. Savi?

2011-01-01

162

Probiotic properties of lactic-acid bacteria: plenty of scope for fundamental R & D  

Microsoft Academic Search

Probiotic products are marketed widely throughout the world. This is especially true of yogurts that contain strains of lactic-acid bacteria of intestinal origin. Consumption of these products is aimed at promoting the wellbeing of the consumer by impacting on the collection of microorganisms that normally inhabit the intestinal tract. The development of scientifically valid probiotics requires more detailed knowledge of

Gerald W Tannock

1997-01-01

163

LACTIC ACID BACTERIA USED IN INOCULANTS FOR SILAGE AS PROBIOTICS FOR RUMINANTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Many studies have shown the beneficial effects on ruminant performance of feeding them with silages inoculated with lactic acid bacteria (LAB). These benefits might derive from probiotic effects. The purpose of the current study was to determine whether LAB included in inoculants for silage can surv...

164

The Effects of Lactic Acid Bacteria+Enzyme Mixture Silage Inoculant on  

Microsoft Academic Search

This study was carried out to determine the effects of a commercial lactic acid bacteria+enzyme inoculants used as silage additive on the fermentation, crude nutritient contents, cell wall fractions and in vitro dry and organic matter digestibilities wheat (Triticum aestivum L.) harvested and ensiled at milk and dough stages of maturity. Sil-All (Altech, UK) containing water soluble Pediococcus acidilactici, Lactobacillus

Wheat Silage

2008-01-01

165

Broad and complex antifungal activity among environmental isolates of lactic acid bacteria  

Microsoft Academic Search

More than 1200 isolates of lactic acid bacteria isolated from different environments were screened for antifungal activity in a dual-culture agar plate assay. Approximately 10% of the isolates showed inhibitory activity and 4% showed strong activity against the indicator mould Aspergillus fumigatus. The antifungal spectra for 37 isolates with strong activity and five isolates with low or no activity were

Jesper Magnusson; Katrin Ström; Stefan Roos; Jörgen Sjögren; Johan Schnürer

2003-01-01

166

Mixed Culture Pre-Ferments of Lactic and Propionic Acid Bacteria for Baking.  

National Technical Information Service (NTIS)

The main aim of the present work was to develop an optimal lactic and propionic acid bacteria mixed culture pre-ferment with naturally fermented propionic acid in a sufficient quantity to prevent bread molding. For this purpose controlled formation of lac...

P. Javanainen

1993-01-01

167

Isolation and Selection of Anti-Candida albicans Producing Lactic Acid Bacteria  

Microsoft Academic Search

The forty isolates of lactic acid bacteria (LAB) were obtained from various fermented foods. The cross streak plate method was used to preliminary screen for antimicrobial activity. LAB were isolated by selective medium, Mann Rogosa Sharpe (MRS). Most of the isolates showed inhibition against Staphylococcus aureus TISTR 517, Bacillus subtilis TISTR 008, Micrococcus luteus TISTR 884, Escherichia coli TISTR 887,

Monthon LERTCANAWANICHAKUL

168

Removal of Aflatoxin B1 from Contaminated Liquid Media by Dairy Lactic Acid Bacteria  

Microsoft Academic Search

In the present study the ability of some dairy strains of lactic acid bacteria to remove aflatoxin B1 from contaminated media was investigated. Twelve out of forty two isolates from yogourt, raw milk and karisk cheese have shown different levels to bind aflatoxin B1 (AFB1). The highest isolates for binding AFB1 were identified as Lactococcus lactis and Sterptococcus thermophilus. Dead

A. A. M. SHAHIN

169

Disease-Dependent Adhesion of Lactic Acid Bacteria to the Human Intestinal Mucosa  

Microsoft Academic Search

Their adhesion to the intestinal mucosa is considered one of the main reasons for the beneficial health effects of specific lactic acid bacteria (LAB). However, the influence of disease on the mucosal adhesion is largely unknown. Adhesion of selected LAB to resected colonic tissue and mucus was determined in patients with three major intestinal diseases (i.e., diverticulitis, rectal carcinoma, and

Arthur C. Ouwehand; Seppo Salminen; Peter J. Roberts; Jari Ovaska; Eeva Salminen

2003-01-01

170

Evaluation of the petrifilm aerobic count plate for enumeration of aerobic marine bacteria from seawater and Caulerpa lentillifera.  

PubMed

The enumeration and evaluation of the activity of marine bacteria are important in the food industry. However, detection of marine bacteria in seawater or seafood has not been easy. The Petrifilm aerobic count plate (ACP) is a ready-to-use alternative to the traditional enumeration media used for bacteria associated with food. The purpose of this study was to evaluate the usefulness of a simple detection and enumeration method utilizing the Petrifilm ACP for enumeration of aerobic marine bacteria from seawater and an edible seaweed, Caulerpa lentillifera. The efficiency of enumeration of total aerobic marine bacteria on Petrifilm ACP was compared with that using the spread plate method on marine agar with 80 seawater and 64 C. lentillifera samples. With sterile seawater as the diluent, a close correlation was observed between the method utilizing Petrifilm ACP and that utilizing the conventional marine agar (r=0.98 for seawater and 0.91 for C. lentillifera). The Petrifilm ACP method was simpler and less time-consuming than the conventional method. These results indicate that Petrifilm ACP is a suitable alternative to conventional marine agar for enumeration of marine microorganisms in seawater and C. lentillifera samples. PMID:20819367

Kudaka, Jun; Horii, Toru; Tamanaha, Koji; Itokazu, Kiyomasa; Nakamura, Masaji; Taira, Katsuya; Nidaira, Minoru; Okano, Sho; Kitahara, Akio

2010-08-01

171

Acetylene degradation by new isolates of aerobic bacteria and comparison of acetylene hydratase enzymes  

Microsoft Academic Search

Aerobic acetylene-degrading bacteria were isolated from soil samples. Two isolates were assigned to the species Rhodococcus opacus, two others to Rhodococcus ruber and Gordona sp. They were compared with known strains of aerobic acetylene-, cyanide-, or nitrile-utilizing bacteria. The acetylene hydratases of R. opacus could be measured in cell-free extracts only in the presence of a strong reductant like titanium(III)

Bettina M Rosner; Frederick A Rainey; Reiner M Kroppenstedt; Bernhard Schink

1997-01-01

172

Organism-adapted specificity of the allosteric regulation of pyruvate kinase in lactic acid bacteria.  

PubMed

Pyruvate kinase (PYK) is a critical allosterically regulated enzyme that links glycolysis, the primary energy metabolism, to cellular metabolism. Lactic acid bacteria rely almost exclusively on glycolysis for their energy production under anaerobic conditions, which reinforces the key role of PYK in their metabolism. These organisms are closely related, but have adapted to a huge variety of native environments. They include food-fermenting organisms, important symbionts in the human gut, and antibiotic-resistant pathogens. In contrast to the rather conserved inhibition of PYK by inorganic phosphate, the activation of PYK shows high variability in the type of activating compound between different lactic acid bacteria. System-wide comparative studies of the metabolism of lactic acid bacteria are required to understand the reasons for the diversity of these closely related microorganisms. These require knowledge of the identities of the enzyme modifiers. Here, we predict potential allosteric activators of PYKs from three lactic acid bacteria which are adapted to different native environments. We used protein structure-based molecular modeling and enzyme kinetic modeling to predict and validate potential activators of PYK. Specifically, we compared the electrostatic potential and the binding of phosphate moieties at the allosteric binding sites, and predicted potential allosteric activators by docking. We then made a kinetic model of Lactococcus lactis PYK to relate the activator predictions to the intracellular sugar-phosphate conditions in lactic acid bacteria. This strategy enabled us to predict fructose 1,6-bisphosphate as the sole activator of the Enterococcus faecalis PYK, and to predict that the PYKs from Streptococcus pyogenes and Lactobacillus plantarum show weaker specificity for their allosteric activators, while still having fructose 1,6-bisphosphate play the main activator role in vivo. These differences in the specificity of allosteric activation may reflect adaptation to different environments with different concentrations of activating compounds. The combined computational approach employed can readily be applied to other enzymes. PMID:23946717

Veith, Nadine; Feldman-Salit, Anna; Cojocaru, Vlad; Henrich, Stefan; Kummer, Ursula; Wade, Rebecca C

2013-07-25

173

The catalytic mechanism for aerobic formation of methane by bacteria.  

PubMed

Methane is a potent greenhouse gas that is produced in significant quantities by aerobic marine organisms. These bacteria apparently catalyse the formation of methane through the cleavage of the highly unreactive carbon-phosphorus bond in methyl phosphonate (MPn), but the biological or terrestrial source of this compound is unclear. However, the ocean-dwelling bacterium Nitrosopumilus maritimus catalyses the biosynthesis of MPn from 2-hydroxyethyl phosphonate and the bacterial C-P lyase complex is known to convert MPn to methane. In addition to MPn, the bacterial C-P lyase complex catalyses C-P bond cleavage of many alkyl phosphonates when the environmental concentration of phosphate is low. PhnJ from the C-P lyase complex catalyses an unprecedented C-P bond cleavage reaction of ribose-1-phosphonate-5-phosphate to methane and ribose-1,2-cyclic-phosphate-5-phosphate. This reaction requires a redox-active [4Fe-4S]-cluster and S-adenosyl-L-methionine, which is reductively cleaved to L-methionine and 5'-deoxyadenosine. Here we show that PhnJ is a novel radical S-adenosyl-L-methionine enzyme that catalyses C-P bond cleavage through the initial formation of a 5'-deoxyadenosyl radical and two protein-based radicals localized at Gly?32 and Cys?272. During this transformation, the pro-R hydrogen from Gly?32 is transferred to the 5'-deoxyadenosyl radical to form 5'-deoxyadenosine and the pro-S hydrogen is transferred to the radical intermediate that ultimately generates methane. A comprehensive reaction mechanism is proposed for cleavage of the C-P bond by the C-P lyase complex that uses a covalent thiophosphate intermediate for methane and phosphate formation. PMID:23615610

Kamat, Siddhesh S; Williams, Howard J; Dangott, Lawrence J; Chakrabarti, Mrinmoy; Raushel, Frank M

2013-04-24

174

Lactic acid bacteria-enclosing poly(epsilon-caprolactone) microcapsules as soil bioamendment.  

PubMed

Free plant growth-promoting bacteria in soil bioamendments (SBA) are easily outnumbered by competitors and predators in agricultural soils. Microencapsulation of the bacteria is an effective technique that provides a suitable microenvironment for their survival. In this study, we attempted to prepare poly(epsilon-caprolactone) (PCL) microcapsules enclosing lactic acid bacteria (LAB), a plant growth-promoting bacteria, using the solvent-evaporation method via water-in-oil-in-water (W/O/W) emulsion. Three preparation parameters in the emulsion system were optimized based on the lactic acid production activity of the encapsulated LAB. A sodium alginate aqueous solution suspending the bacteria, a dichloromethane solution with dissolved PCL, and a poly(vinyl alcohol) aqueous solution were used as the inner aqueous phase (W(i)), the oil phase (O), and the outer aqueous phase (W(o)), respectively. Suitable volume ratio of W(i) to O, concentration of sodium alginate in W(i), and the molecular weight of PCL in O were 0.1, 1.0%, and 40 kDa, respectively. The lactic acid production activity of the microcapsules prepared under the optimized conditions was approximately nine times higher than that of commercial SBA. Application to soil demonstrated that the microcapsules are effective in the removal of the root-knot nematodes. PMID:18930004

Takei, Takayuki; Yoshida, Masahiro; Hatate, Yasuo; Shiomori, Koichiro; Kiyoyama, Shiro

2008-09-01

175

The Effect of Lactic Acid, Nisin Whey Permeate, Sodium Chloride and Related Combinations on Aerobic Plate Count and the Sensory Characteristics of Rainbow Trout  

Microsoft Academic Search

The inhibitory effects of 2.5 g\\/kg lactic acid, 30 g\\/kg whey permeate, 20 g\\/kg sodium chloride and their combinations on the total aerobic counts of minced fish were studied. Whey permeate was produced by a nisin-producingLactococcus lactisstrain. The applicability of lactic acid and whey permeate as bio-preservatives was also studied through the use of quantitative sensory profiling techniques. Bacterial growth

Anne Nykänen; Anja Lapveteläinen; Rose-Marie Hietanen; Heikki Kallio

1998-01-01

176

Distinct distribution pattern of abundance and diversity of aerobic anoxygenic phototrophic bacteria in the global ocean  

Microsoft Academic Search

Summary Aerobic anoxygenic phototrophic bacteria (AAPB) are an important bacterial group with capability of har- vesting light energy, and appear to have a particular role in the ocean's carbon cycling. Yet the signifi- cance of AAPB relative to total bacteria (AAPB%) in different marine regimes are still controversial, and variation trend of genetic diversity of AAPB along environmental gradients remains

Nianzhi Jiao; Yao Zhang; Yonghui Zeng; Ning Hong; Rulong Liu; Feng Chen; Pinxian Wang

2007-01-01

177

Novel method to extract large amounts of bacteriocins from lactic acid bacteria.  

PubMed

Antimicrobial peptides, bacteriocins, produced by lactic acid bacteria were adsorbed on the cells of producing strains and other gram-positive bacteria. pH was a crucial factor in determining the degree of adsorption of these peptides onto cell surfaces. In general, between 93 and 100% of the bacteriocin molecules were adsorbed at pHs near 6.0, and the lowest (< or = 5%) adsorption took place at pH 1.5 to 2.0. On the basis of this property, a novel isolation method was developed for bacteriocins from four genera of lactic acid bacteria. By using this method we made preparations of pediocin AcH, nisin, sakacin A, and leuconocin Lcm1 that were potent and concentrated. This method produced a higher yield than isolation procedures, which rely on precipitation of the bacteriocins from the cell-free culture liquor. It is simple and can be used to produce large quantities of bacteriocins from lactic acid bacteria to be used as food biopreservatives. PMID:1444369

Yang, R; Johnson, M C; Ray, B

1992-10-01

178

Lactic Acid Bacteria Inducing a Weak Interleukin12 and Tumor Necrosis Factor Alpha Response in Human Dendritic Cells Inhibit Strongly Stimulating Lactic Acid Bacteria but Act Synergistically with Gram-Negative Bacteria  

Microsoft Academic Search

The development and maintenance of immune homeostasis indispensably depend on signals from the gut flora. Lactic acid bacteria (LAB), which are gram-positive (G) organisms, are plausible significant players and have received much attention. Gram-negative (G) commensals, such as members of the family Entero- bacteriaceae, may, however, be immunomodulators that are as important as G organisms but tend to be overlooked.

Louise Hjerrild Zeuthen; Hanne Risager Christensen; H. Frokiaer

2006-01-01

179

Antibiotic resistance in food lactic acid bacteria—a review  

Microsoft Academic Search

Antibiotics are a major tool utilized by the health care industry to fight bacterial infections; however, bacteria are highly adaptable creatures and are capable of developing resistance to antibiotics. Consequently, decades of antibiotic use, or rather misuse, have resulted in bacterial resistance to many modern antibiotics. This antibiotic resistance can cause significant danger and suffering for many people with common

Shalini Mathur; Rameshwar Singh

2005-01-01

180

Action of lysozyme and nisin mixtures against lactic acid bacteria  

Microsoft Academic Search

Lysozyme was formulated together with nisin for usage against food spoilage lactobacilli. The mixtures demonstrated improved minimal inhibitory concentrations (MIC), compared to the parent compounds, for many of the bacteria and media tested, including high salt media in which lysozyme lost virtually all of its activity. Synergy was also observed through measurement of the kinetics of bacterial killing of L.

Wilfred Chung; Robert E. W Hancock

2000-01-01

181

Lactic acid starter and probiotic bacteria: a comparative “in vitro” study of probiotic characteristics and biological barrier resistance  

Microsoft Academic Search

Probiotic characteristics (deconjugation of bile salts, hydrophobicity and ?-galactosidase activity) and the resistance to biological barriers (gastric juice and bile salts) of 24 strains of lactic acid starter bacteria (Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus and Lactococcus lactis) and 24 strains of probiotic bacteria (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus and bifidobacteria) were compared. Among the probiotic bacteria tested, Lactobacillus

C. G. Vinderola; J. A. Reinheimer

2003-01-01

182

Phenolic Biotransformations during Conversion of Ferulic Acid to Vanillin by Lactic Acid Bacteria  

PubMed Central

Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives.

Kaur, Baljinder; Kumar, Balvir

2013-01-01

183

Phenolic Biotransformations during Conversion of Ferulic Acid to Vanillin by Lactic Acid Bacteria.  

PubMed

Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives. PMID:24066293

Kaur, Baljinder; Chakraborty, Debkumar; Kumar, Balvir

2013-08-28

184

Aerobic Anoxygenic Phototrophic Bacteria Attached to Particles in Turbid Waters of the Delaware and Chesapeake Estuaries  

Microsoft Academic Search

Aerobic anoxygenic phototrophic (AAP) bacteria are photoheterotrophs that, if abundant, may be biogeo- chemically important in the oceans. We used epifluorescence microscopy and quantitative PCR (qPCR) to examine the abundance of these bacteria by enumerating cells with bacteriochlorophyll a (bChl a) and the light-reaction center gene pufM, respectively. In the surface waters of the Delaware estuary, AAP bacteria were abundant,

Lisa A. Waidner; David L. Kirchman

2007-01-01

185

Efficacy of Lactic Acid Bacteria (LAB) supplement in management of constipation among nursing home residents  

Microsoft Academic Search

BACKGROUND: Constipation is a significant problem in the elderly, specifically nursing home and\\/or extended-care facility residents are reported to suffer from constipation. Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as diarrhea and constipation effect. The objective of this study was to investigate the efficacy

Hyang Mi An; Eun Hye Baek; Seok Jang; Do Kyung Lee; Mi Jin Kim; Jung Rae Kim; Kang Oh Lee; Jong Gi Park; Nam Joo Ha

2010-01-01

186

Development and Evaluation of Genome-Probing Microarrays for Monitoring Lactic Acid Bacteria  

Microsoft Academic Search

The genome-probing microarray (GPM) was developed for quantitative, high-throughput monitoring of commu- nity dynamics in lactic acid bacteria (LAB) fermentation through the deposit of 149 microbial genomes as probes on a glass slide. Compared to oligonucleotide microarrays, the specificity of GPM was remarkably increased to a species-specific level. GPM possesses about 10- to 100-fold higher sensitivity (2.5 ng of genomic

Jin-Woo Bae; Sung-Keun Rhee; J. R. Park; W.-H. Chung; Y.-D. Nam; I. Lee; H. Kim; Y.-H. Park

2005-01-01

187

Risk Assessment of Genetically Modified Lactic Acid Bacteria Using the Concept of Substantial Equivalence  

Microsoft Academic Search

The use of food-grade microorganisms such as lactic acid bacteria (LAB) is one of the most promising methods for delivering\\u000a health promoting compounds. Since it is not always possible to obtain strains that have the ability to produce specific compounds\\u000a naturally or that produce them in sufficient quantities to obtain physiological responses, genetic modifications can be performed\\u000a to improve their

Jean Guy LeBlanc; Douwe Van Sinderen; Jeroen Hugenholtz; Jean-Christophe Piard; Fernando Sesma; Graciela Savoy de Giori

2010-01-01

188

Anti-listerial inhibitory lactic acid bacteria isolated from commercial cold smoked salmon  

Microsoft Academic Search

The natural microflora of cold-smoked fish at the end of shelf-life are lactic acid bacteria (LAB). Some of these display a capacity to inhibit spoilage as well as several strains of pathogenic micro-organisms, e.g. Listeria monocytogenes which is isolated frequently from cold-smoked salmon (CSS).Eight batches of sliced vacuum-packed CSS from Norway, Scotland and Spain were collected at retail. Packs were

Elisabetta Tomé; Paula Teixeira; Paul A. Gibbs

2006-01-01

189

Assuring the continued safety of lactic acid bacteria used as probiotics  

Microsoft Academic Search

Lactic acid bacteria have long been used to improve the safety of foods through fermentation. Some fermented products were\\u000a also early used for their perceived health benefits, which lead to the development of probiotics as we now know them. Probiotics\\u000a mainly belong to the genera Lactobacillus and Bifidobacterium. Most members of these genera are not considered pathogens or even opportunistic

Miguel Gueimonde; Rafael Frias; Arthur C. Ouwehand

2006-01-01

190

Distribution and genetic diversity of lactic acid bacteria from traditional fermented sausage  

Microsoft Academic Search

This study was conducted to investigate the distribution and genetic diversity of the native lactic acid bacteria (LAB) population in nem chua, a popular traditional Vietnamese uncooked fermented sausage. A total of 74 LAB isolates were identified and their molecular fingerprints were obtained using repetitive-PCR (rep-PCR) and pulse-field gel electrophoresis (PFGE). The results revealed that the majority of LAB isolates

Khanh T. M. Tran; Bee K. May; Peter M. Smooker; Thi T. H. Van; Peter J. Coloe

2011-01-01

191

New Procedure for the Detection of Lactic Acid Bacteria in Vegetables Producing Antibacterial Substances  

Microsoft Academic Search

There is an increasing interest in antibacterial-producing lactic acid bacteria (LAB) as protective cultures on ready-to-use vegetables. A new procedure for detection of active strains has been developed, which consisted of anaerobic incubation (30 °C, 2 d) of juice of ‘i ceberglettuce’ on MRS agar or lactose-bromcresol purple (LBP) agar followed by overlaying with the indicator strain in soft agar

Rosario Gómez; Marina Muñoz; Begoña de Ancos; M. Pilar Cano

2002-01-01

192

Pediocin PA1, a Wide-Spectrum Bacteriocin from Lactic Acid Bacteria  

Microsoft Academic Search

Referee: Dr. Helen Dodd, Food Safety Science Division, Institute of Food Research, Norwich Research Park, Colney NR4 7UA, Norwich, United Kingdom Pediocin PA-1 is a broad-spectrum lactic acid bacteria bacteriocin that shows a particularly strong activity against Listeria monocytogenes, a foodborne pathogen of special concern among the food industries. This antimicrobial peptide is the most extensively studied class IIa (or

Juan M. Rodríguez; María I. Martínez; Jan Kok

2002-01-01

193

Isolation of cholesterol-lowering lactic acid bacteria from human intestine for probiotic use  

Microsoft Academic Search

Cholesterol-lowering effect of lactic acid bacteria (LAB: Streptococcus, Lactobacillus and Bifidobacterium) is well- known. Thus, we investigated LAB isolated from human intestine on the cholesterol-lowering effect in vitro. Seven Streptococcus (61.1%), 11 Lactobacillus (71.8%) and 7 Bifidobacterium (27.9%) were isolated as acid (pH 2.5 and 3.0) and bile (0.3% oxgall) tolerant strains. Streptococcus HJS-1, Lactobacillus HJL-37 and Bifidobacterium HJB-4 were

Hyeong-Jun Lim; So-Young Kim; Wan-Kyu Lee

194

Fermented Milk–Starch and Milk–Inulin Products as Vehicles for Lactic Acid Bacteria  

Microsoft Academic Search

Formulations using cassava starch or inulin plus milk were fermented with three different lactic acid bacteria (LAB) strains: Lactobacillus plantarum D34, Lactobacillus sp. SLH6, and Streptococcus thermophilus ST4. Growth and acidification were followed in 3% powdered milk (M3), 3% milk–6% starch (M3-S6), and 3% milk–6% inulin (M3-In6). D34 and SLH6 growth was enhanced by starch in M3-S6, when compared to

ANGELA ZULETA; MARÍA I. SARCHI; MARÍA E. RIO; MARÍA E. SAMBUCETTI; MARCELO MORA; SUSANA V. DE FABRIZIO; JOSÉ L. PARADA

2004-01-01

195

Preservation of porcine blood quality by means of lactic acid bacteria  

Microsoft Academic Search

The capacity of 12 lactic acid bacteria (LAB) strains to preserve porcine blood during storage was evaluated. A general ability of LAB to prevent blood’s hemolysis and to maintain the functional properties of plasma was observed. Two strains, PS99 (Enterococcus raffinosus) and TA43 (Lactobacillus reuteri), were selected for studies at 5°C according to their antibacterial activity in blood stored at

Eduard Dàvila; Elena Saguer; Mònica Toldrà; Carmen Carretero; Dolors Parés

2006-01-01

196

The effects on vegetative cells and spores of three bacteriocins from lactic acid bacteria  

Microsoft Academic Search

The sensitivities of vegetative cells of strains ofListeria, Clostridium, Staphylococcus, Lactococcus, Lactobacillus, MicrococcusandPediococcus, and of spores ofClostridiumandBacillusto three broad spectrum bacteriocins (nisin A, nisin Z and pediocin) from lactic acid bacteria were determined by a critical dilution micro-assay. The minimal inhibitory concentrations (MIC) of partially purified bacteriocins, prepared by a pH-dependent adsorption\\/desorption process, were determined and expressed in arbitrary units

J. Meghrous; C. Lacroix; R. E. Simard

1999-01-01

197

Lactic acid bacteria from chicken carcasses with inhibitory activity against Salmonella spp. and Listeria monocytogenes  

Microsoft Academic Search

This study was conducted to isolate psychrotrophic lactic acid bacteria (LAB) from chicken carcasses with inhibitory activity against strains of Salmonella spp. and Listeria monocytogenes. A total of 100 broiler samples were examined for the presence of LAB. Ninety-two LAB isolates that showed antimicrobial effects against Salmonella spp. and L. monocytogenes were further analysed to examine their LAB (Gram-positive, catalase negative,

I. Sakaridis; N. Soultos; C. I. Dovas; E. Papavergou; I. Ambrosiadis; P. Koidis

198

Temporal Effects of Lactic Acid Bacteria Probiotic Culture on Salmonella in Neonatal Broilers  

Microsoft Academic Search

We evaluated the ability of a commercially available lactic acid bacteria-based probiotic culture (LAB)toreduceSalmonellaEnteritidisorSalmonellaTyphi- murium in day-of-hatch broiler chicks. In these experi- ments, chicks were challenged with Salmonella Enteritidis or Salmonella Typhimurium and treated with LAB 1-h postchallenge. Following treatment, cecal tonsils and ceca were aseptically collected for Salmonella Enteritidis or Sal- monella Typhimurium enrichment or Salmonella Enteriti- dis enumeration,

J. P. Higgins; S. E. Higgins; J. L. Vicente; A. D. Wolfenden; G. Tellez; B. M. Hargis

199

Influence of intensive and extensive breeding on lactic acid bacteria isolated from Gallus gallus domesticus ceca  

Microsoft Academic Search

In the present study, lactic acid bacteria (LAB) from the cecum of chickens bred either under intensive (commercial broilers) or extensive (free-range) conditions were isolated, identified and some of their probiotic characteristics determined. The LAB identified by 16S–23S rRNA PCR-ARDRA were mainly of Lactobacillus species and to a lesser extent of Enterococcus spp. for all animals. Free-range chickens showed a

Marcelo R. Souza; João L. Moreira; Flávio H. F. Barbosa; Mônica M. O. P. Cerqueira; Álvaro C. Nunes; Jacques R. Nicoli

2007-01-01

200

Biogenic amines in cold-smoked fish fermented with lactic acid bacteria  

Microsoft Academic Search

It has been proved in previous studies that fish can be fermented by lactic acid bacteria (LAB). Added glucose must be at\\u000a concentrations of almost 1% to reduce the pH to <5.3, a level which corresponds to the safe pH values for meat products. Because\\u000a some LAB and some contaminating microbes form biogenic amines, this study was conducted to examine

E. Petäjä; S. Eerola; P. Petäjä

2000-01-01

201

Quantitative detection of lactic acid bacteria in dried sourdoughs using real-time PCR  

Microsoft Academic Search

A real-time PCR system with 16S rRNA gene-targeted group-specific primers was developed to quantitatively detect lactic acid\\u000a bacteria (LAB) of the genera Lactobacillus, Leuconostoc, Pediococcus, and Weissella in different types of commercially available dried sourdoughs. Despite a high degree of degradation in the DNA isolated from\\u000a the doughs, the 341-bp 16S rRNA gene fragment of the sourdough LAB biota could

Melanie Wieschebrock; Marion Seitter; Christian Hertel

202

Identification of Lactic Acid Bacteria from Chili Bo, a Malaysian Food Ingredient  

Microsoft Academic Search

Ninety-two strains of lactic acid bacteria (LAB) were isolated from a Malaysian food ingredient, chili bo, stored for up to 25 days at 28°C with no benzoic acid (product A) or with 7,000 mg of benzoic acid kg21 (product B). The strains were divided into eight groups by traditional phenotypic tests. A total of 43 strains were selected for comparison

JØRGEN J. LEISNER; BRUNO POT; HENRIK CHRISTENSEN; GULAM RUSUL; JOHN E. OLSEN; BEE WAH WEE; KHARIDAH MUHAMAD; HASANAH M. GHAZALI

1999-01-01

203

Tyrosine and histidine-decarboxylase positive lactic acid bacteria and enterococci in dry fermented sausages  

Microsoft Academic Search

Lactic acid bacteria (LAB) and enterococci were isolated immediately after stuffing (day 0), at the end of ripening (28th day) and at the end of storage (112th day) from dry fermented sausages produced by two different producers (K; R) in two diameters (4.5 and 7cm) using either of two spice mixtures (P; H) and either of two starter cultures (Pediococcus

T. Komprda; P. Sládková; E. Petirová; V. Dohnal; R. Burdychová

2010-01-01

204

Characterisation and technological properties of psychotropic lactic acid bacteria strains isolated from Tunisian raw milk  

Microsoft Academic Search

A total of 102 wild lactic acid bacteria (LAB: 32%Lactococcus ssp.lactis, 23%Lactobacillus plantarum, 22%Lactobacillus pentosus, 7%Leuconostoc mesenteroides, 5%Lactobacillus brevis), isolated from Tunisian refrigerated raw milk obtained from collected centres, were screened according to their antimicrobial\\u000a activities against spoilage and undesirable micro-organisms. Nineteen isolates having the most important antimicrobial activities\\u000a were selected. Amplification of 16S\\/23S spacer regions of these selected LAB

Olfa Ben Moussa; Melika Mankaï; Khaola Setti; Mouna Boulares; Medini Maher; Mnasser Hassouna

2008-01-01

205

Antimicrobial Activities of Lactic Acid Bacteria Strains Isolated from Burkina Faso Fermented Milk  

Microsoft Academic Search

Abstract: Eight strains of lactic acid bacteria producing,bacteriocin were,isolated from,Burkina Faso fermented milk samples. These strains were identified to species: Lactobacillus fermentum, Pediococcus spp., Leuconostoc mesenteroides subsp. meseteroides, Lactococcus. Isolated bacteriocin exhibited antibacterial activity against Enterococcus faecalis103907 CIP, Bacillus cereus 13569 LMG,Staphylococcus aureusATCC 25293,Escherichia coli105182 CIP using the agar drop diffusion test. The inhibition diameters obtained wi th bacteriocin are

2004-01-01

206

Antihypertensive peptides and ?-aminobutyric acid from prozyme 6 facilitated lactic acid bacteria fermentation of soymilk  

Microsoft Academic Search

Soymilk was fermented with five lactic acid bacteria (Lactobacillus casei, Lactobacillus acidophilus, Streptococcus thermophilus, Lactobacillus bulgaricus, Bifidobacterium longum) for up to 30h at 42°C. A protease, prozyme 6, was added 5h after fermentation. The whey was separated from the fermented soymilk and then freeze-dried. As the fermentation time extended to 30h, pH decreased from 6.5 to 4.1, soluble protein content

J. S. Tsai; Y. S. Lin; B. S. Pan; T. J. Chen

2006-01-01

207

Probiotic Characteristics of Lactic Acid Bacteria Isolated from Traditional Fermented Milk ‘Dahi’ in Bangladesh  

Microsoft Academic Search

3 Abstract: We evaluated the probiotic characteristics (pH and acid production, acid and bile acid tolerance and Angiotensin I-converting enzyme (ACE) inhibitory activity) of lactic acid bacteria isolated from traditional fermented milk 'Dahi' in Bangladesh. Among the tested strains, Lactobacillus delbrueckii subsp. bulgaricus M3 40-3 displayed more tolerance at acidic medium as well as highest acid production (2.13%). Whereas, highest

Kaname Togo; Minoru Ueda; Taku Miyamoto

2007-01-01

208

Interaction between human polymorphonuclear leukocytes (PMNL) and bacteria cultivated in aerobic and anaerobic conditions.  

PubMed

A study was performed on one strain of Escherichia coli (E. coli K12D22) and on one strain of Salmonella braenderup (S. braenderup S2828). The physico-chemical surface properties of the bacteria were strongly influenced by oxygen supply, viz. anaerobic growth conditions resulted in increasing of hydrophobicity. Interaction between human polymorphonuclear leukocytes and bacteria, measured as chemiluminescence, was more efficient when bacteria had been cultivated anaerobically than when cultivated aerobically. The results show the importance of the surface hydrophobicity of bacteria in interaction with PMNL, and the role of the growth conditions of bacteria in that process. PMID:3893034

Maluszynska, G M; Stendahl, O; Magnusson, K E

1985-04-01

209

Occurrence of Arginine Deiminase Pathway Enzymes in Arginine Catabolism by Wine Lactic Acid Bacteria  

PubMed Central

l-Arginine, an amino acid found in significant quantities in grape juice and wine, is known to be catabolized by some wine lactic acid bacteria. The correlation between the occurrence of arginine deiminase pathway enzymes and the ability to catabolize arginine was examined in this study. The activities of the three arginine deiminase pathway enzymes, arginine deiminase, ornithine transcarbamylase, and carbamate kinase, were measured in cell extracts of 35 strains of wine lactic acid bacteria. These enzymes were present in all heterofermentative lactobacilli and most leuconostocs but were absent in all the homofermentative lactobacilli and pediococci examined. There was a good correlation among arginine degradation, formation of ammonia and citrulline, and the occurrence of arginine deiminase pathway enzymes. Urea was not detected during arginine degradation, suggesting that the catabolism of arginine did not proceed via the arginase-catalyzed reaction, as has been suggested in some earlier studies. Detection of ammonia with Nessler's reagent was shown to be a simple, rapid test to assess the ability of wine lactic acid bacteria to degrade arginine, although in media containing relatively high concentrations (>0.5%) of fructose, ammonia formation is inhibited.

Liu, S.; Pritchard, G. G.; Hardman, M. J.; Pilone, G. J.

1995-01-01

210

Antibacterial effects of enniatins J(1) and J(3) on pathogenic and lactic acid bacteria.  

PubMed

Enniatins (ENs) are N-methylated cyclohexadepsipeptides, secondary metabolites produced by various species of the genus Fusarium. They are known to act as antifungal, antiyeast and antibacterial and to possess antiinsecticidal and phytotoxic properties. In this study we evaluated for the first time the antibiotic effect of pure fractions of EN J(1) and J(3) on several pathogenic strains and lactic acid bacteria. The ENs J(1) and J(3) were purified from the fermentation extract of Fusarium solani growth on solid medium of wheat kamut, using the technique of the low pressure liquid chromatography (LPLC) followed by a semipreparative liquid chromatography (LC). The purity and the structure of the isolated compound were confirmed by electrospray ionization-mass spectrometry study-linear ion trap (ESI-MS-LIT). The use of both chromatographic techniques have permitted to produce and purify 47mg of the En J(1) and 50mg of the EN J(3) with a mean purity of 98% completely characterized with the technique of the ESI-MS-LIT. Microbial bioassay analyses were carried out by incubation in MRSA and TSA for acid lactic and pathogenic bacteria, respectively during 24h at 37°C. None of the tested strains were inhibited by a 1ng dose of EN J(1) and J(3). These compounds were only not effective against Listeria monocytogenes, Pseudomonas aeruginosa and Salmonella enteric. This study highlight ENs J(1) and J(3) could be potentially effective antibacterial agents against several pathogenic and lactic acid bacteria. PMID:21742008

Sebastià, Natividad; Meca, Giuseppe; Soriano, José Miguel; Mañes, Jordi

2011-07-01

211

Hygienic quality of commercial minced meat as indicated by aerobic micro-organisms and Coliform bacteria  

Microsoft Academic Search

The hygienic quality of commercial beef and beef-pork minced meat was examined using aerobic micro-organisms and Coliform\\u000a bacteria as indicator organisms. About 70% of the samples examined were of good quality and about 30% of tolerable quality.\\u000a Aerobic micro-organisms can be recommended as an initial means of monitoring the hygienic quality of minced meat, being better\\u000a for this purpose than

Anneli Skrökki

1997-01-01

212

Studying the Life Cycle of Aerobic Endospore-forming Bacteria in Soil  

Microsoft Academic Search

\\u000a Members of the genus Bacillus are commonly isolated from soils, with members of the Bacillus cereus group being prevalent. Our knowledge of the ecology of B. cereus and other aerobic spore-forming bacteria in soil is far from complete. We have developed an in terra approach to study soil-associated aerobes, using filter-sterilized soil extracted soluble organic matter (SESOM). B. cereus is

Volker S. Brözel; Yun Luo; Sebastien Vilain

213

Prevention of Aerobic Spoilage of Maize Silage by a Genetically Modified Killer Yeast, Kluyveromyces lactis, Defective in the Ability To Grow on Lactic Acid  

Microsoft Academic Search

In this study, we propose a new process of adding a genetically modified killer yeast to improve the aerobic stability of silage. Previously constructed Kluyveromyces lactis killer strain PCK27, defective in growth on lactic acid due to disruption of the gene coding for phosphoenolpyruvate carboxykinase, a key enzyme for gluco- neogenesis, inhibited the growth of Pichia anomala inoculated as an

H. K. KITAMOTO; A. HASEBE; S. OHMOMO; E. G. SUTO; M. MURAKI; Y. IIMURA

1999-01-01

214

Isolation and characterization of lactic acid bacteria strains with ornithine producing capacity from natural sea salt  

Microsoft Academic Search

Two lactic acid bacteria (LAB) having ornithine-producing capacity were isolated from Korean natural sea salt. They were Gram-positive,\\u000a short rod-type bacteria, and able to grow anaerobically with CO2 production. The isolates grew well on MRS broth at 30–37°C and a pH of 6.5–8.0. The optimum temperature and pH for growth\\u000a are 37°C and pH 7.0. The isolates fermented D-ribose, D-galactose,

Jin-Ju Yu; Suk-Heung Oh

2010-01-01

215

Behavior of Psychrotrophic Lactic Acid Bacteria Isolated from Spoiling Cooked Meat Products  

PubMed Central

Three kinds of lactic acid bacteria were isolated from spoiling cooked meat products stored below 10°C. They were identified as Leuconostoc mesenteroides subsp. mesenteroides, Lactococcus lactis subsp. lactis, and Leuconostoc citreum. All three strains grew well in MRS broth at 10°C. In particular, L. mesenteroides subsp. mesenteroides and L. citreum grew even at 4°C, and their doubling times were 23.6 and 51.5 h, respectively. On the other hand, although the bacteria were initially below the detection limit (<10 CFU/g) in model cooked meat products, the bacterial counts increased to 108 CFU/g at 10°C after 7 to 12 days.

Hamasaki, Yoshikatsu; Ayaki, Mitsuko; Fuchu, Hidetaka; Sugiyama, Masaaki; Morita, Hidetoshi

2003-01-01

216

Classification of lactic acid bacteria with UV-resonance Raman spectroscopy.  

PubMed

UV-resonance Raman spectroscopy is applied as a method for the identification of lactic acid bacteria from yogurt. Eight different strains of bacteria from Lactobacillus acidophilus, L. delbrueckii ssp. bulgaricus, and Streptococcus thermophilus were investigated. At an excitation wavelength of 244 nm signals from nucleic acids and proteins are selectively enhanced. Classification was accomplished using different chemometric methods. In a first attempt, the unsupervised methods hierarchical cluster analysis and principal component analysis were applied to investigate natural grouping in the data. In a second step the spectra were analyzed using several supervised methods: K-nearest neighbor classifier, nearest mean classifier, linear discriminant analysis, and support vector machines. PMID:16421858

Gaus, K; Rösch, P; Petry, R; Peschke, K-D; Ronneberger, O; Burkhardt, H; Baumann, K; Popp, J

2006-07-01

217

A combination of two lactic acid bacteria improves the hydrolysis of gliadin during wheat dough fermentation.  

PubMed

The evaluation of gliadin hydrolysis during dough fermentation by using two lactic acid bacteria, Lactobacillus plantarum CRL 775 and Pediococcus pentosaceus CRL 792, as pooled cell suspension (LAB) or cell free extract (CFE) was undertaken. The CFE pool produced a greater (121%) increase in amino acid concentration than the LAB pool (70-80%). These results were correlated with the decrease (76,100 and 64,300 ppm) in the gliadin concentration of doughs supplemented with CFE and LAB, respectively, compared to control doughs. The use of LAB peptidases seemed to be a viable technologic alternative to reduce the gliadin concentration in wheat dough without using living bacteria as starter. PMID:22986210

Gerez, Carla Luciana; Dallagnol, Andrea; Rollán, Graciela; Font de Valdez, Graciela

2012-07-20

218

Complete decomposition of biological waste sludge by thermophilic aerobic bacteria  

Microsoft Academic Search

Conventional activated sludge (AS) process is an economical and effective biooxidation process although a large amount of excess sludge is necessarily generated. We have developed a new zero- discharge AS process, in which no excess sludge is generated. It was formed by combining the conventional AS process with thermophilic aerobic sludge digester in which excess sludge is solubilized by thermophilic

Y. Sakai; T. Aoyagi; N. Shiota; A. Akashi; S. Hasegawa

2000-01-01

219

Genotypic identification of some lactic acid bacteria by amplified fragment length polymorphism analysis and investigation of their potential usage as starter culture combinations in Beyaz cheese manufacture.  

PubMed

In this study, 2 different starter culture combinations were prepared for cheesemaking. Starter culture combinations were formed from 8 strains of lactic acid bacteria. They were identified as Lactococcus lactis ssp. lactis (2 strains), Lactobacillus plantarum (5 strains), and Lactobacillus paraplantarum (1 strain) by amplified fragment length polymorphism analysis. The effects of these combinations on the physicochemical and microbiological properties of Beyaz cheeses were investigated. These cheeses were compared with Beyaz cheeses that were produced with a commercial starter culture containing Lc. lactis ssp. lactis and Lc. lactis ssp. cremoris as control. All cheeses were ripened in brine at 4 degrees C for 90 d. Dry matter, fat in dry matter, titratable acidity, pH, salt in dry matter, total N, water-soluble N, and ripening index were determined. Sodium dodecyl sulfate-PAGE patterns of cheeses showed that alpha(S)-casein and beta-casein degraded slightly during the ripening period. Lactic acid bacteria, total mesophilic aerobic bacteria, yeast, molds, and coliforms were also counted. All analyses were repeated twice during d 7, 30, 60, and 90. The starter culture combinations were found to be significantly different from the control group in pH, salt content, and lactobacilli, lactococci, and total mesophilic aerobic bacteria counts, whereas the cheeses were similar in fat, dry matter content, and coliform, yeast, and mold counts. The sensory analysis of cheeses indicated that textural properties of control cheeses presented somewhat lower scores than those of the test groups. The panelists preferred the tastes of treatment cheeses, whereas cheeses with starter culture combinations and control cheeses had similar scores for appearance and flavor. These results indicated that both starter culture combinations are suitable for Beyaz cheese production. PMID:20059897

Karahan, A G; Ba?yi?it Kiliç, G; Kart, A; Sanlidere Alo?lu, H; Oner, Z; Aydemir, S; Erku?, O; Harsa, S

2010-01-01

220

Aerobic mesophilic and psychrotrophic sporeforming bacteria in buffalo milk.  

PubMed

Seasonal variation of the population of aerobic sporeformers in raw milk was higher in summer than in other seasons. Least variation was in fall, but variation in winter and spring was similar. Aerobic mesophilic sporeformers in raw milk consisted mainly of Bacillus subtilis (42.5%) and Bacillus megaterium (34.8%), followed by Bacillus circulans (4.9%), Bacillus cereus (4.6%), Bacillus pumilus (2.9%), Bacillus polymyxa (2.8%), Bacillus licheniformis (1.9%), Bacillus badius (1.5%), Bacillus brevis (1.3%), Bacillus pulvifaciens (1.2%), Bacillus coagulans (1.1%), and Bacillus firmus (.5%). Comparing these findings with those previously obtained for the same area reveal noticeable variations. The psychrotrophic Bacillus strains were cereus (42.6%), pumilus (31.9%), badius (12.8%), licheniformis (10.6%), and firmus (2.1%). PMID:6886164

Shehata, A E; Magdoub, M N; Sultan, N E; El-Samragy, Y A

1983-06-01

221

Distribution, diversity and ecology of aerobic CO-oxidizing bacteria  

Microsoft Academic Search

Numerous studies indicate that carbon monoxide (CO) participates in a broader range of processes than any other single molecule, ranging from subcellular to planetary scales. Despite its toxicity to many organisms, a diverse group of bacteria that span multiple phylogenetic lineages metabolize CO. These bacteria are globally distributed and include pathogens, plant symbionts and biogeochemically important lineages in soils and

Carolyn F. Weber; Gary M. King

2007-01-01

222

Developments in the Taxonomy of Aerobic, Endospore-forming Bacteria  

Microsoft Academic Search

\\u000a \\u000a Bacillus holds an important place in the history of bacteriology. With observations upon Bacillus subtilis and its spores Cohn discredited the theory of spontaneous generation, and with his demonstration of the life history of B. anthracis in 1876 Robert Koch proved the germ theory of disease and founded medical bacteriology. Later, Bacillus became defined as a genus of aerobic, endospore-forming

Niall A. Logan; Gillian Halket

223

Effect of phenolic acids on glucose and organic acid metabolism by lactic acid bacteria from wine.  

PubMed

The influence of phenolic (p-coumaric, caffeic, ferulic, gallic and protocatechuic) acids on glucose and organic acid metabolism by two strains of wine lactic acid bacteria (Oenococcus oeni VF and Lactobacillus hilgardii 5) was investigated. Cultures were grown in modified MRS medium supplemented with different phenolic acids. Cellular growth was monitored and metabolite concentrations were determined by HPLC-RI. Despite the strong inhibitory effect of most tested phenolic acids on the growth of O. oeni VF, the malolactic activity of this strain was not considerably affected by these compounds. While less affected in its growth, the capacity of L. hilgardii 5 to degrade malic acid was clearly diminished. Except for gallic acid, the addition of phenolic acids delayed the metabolism of glucose and citric acid in both strains tested. It was also found that the presence of hydroxycinnamic acids (p-coumaric, caffeic and ferulic) increased the yield of lactic and acetic acid production from glucose by O. oeni VF and not by L. hilgardii 5. The results show that important oenological characteristics of wine lactic acid bacteria, such as the malolactic activity and the production of volatile organic acids, may be differently affected by the presence of phenolic acids, depending on the bacterial species or strain. PMID:19376463

Campos, Francisco M; Figueiredo, Ana R; Hogg, Tim A; Couto, José A

2009-02-07

224

Anti-diabetic effects of lactic acid bacteria in normal and type 2 diabetic mice  

PubMed Central

The antidiabetic effects of lactic acid bacteria were investigated using mice. In Experiment 1, normal ICR mice were loaded with sucrose or starch with or without viable Lactobacillus rhamnosus GG cells. GG significantly inhibited postprandial blood glucose levels when administered with sucrose or starch. In Experiment 2, KK-Ay mice, a model of genetic type 2 diabetes, were given a basal diet containing viable GG cells or viable Lactobacillus delbrueckii subsp. bulgaricus cells for 6 weeks. Viable GG cells significantly inhibited fasting blood glucose, postprandial blood glucose in a glucose tolerance test and HbA1c. Such effects were not shown by viable L. bulgaricus cells. In Experiment 3, the KK-Ay mice were given a basal diet containing viable GG cells or heat-treated GG cells for 3 weeks. The viable GG cells significantly suppressed fasting blood glucose and impaired glucose tolerance, but the heat-treated GG showed no effects. These results demonstrated that GG decreased the postprandial blood glucose in ICR mice, and that the antidiabetic activity of lactic acid bacteria on the KK-Ay mice differed depending on the bacterial strain and whether the bacterium is viable when it arrives in the intestine. In the present study, we conclude that the antidiabetic activity may result from continuous inhibition of the postprandial blood glucose through suppression of glucose absorption from the intestine. These findings indicate that specific strains of lactic acid bacterium can be expected to be beneficial for the management of type 2 diabetes.

Honda, Kayoko; Moto, Mihoko; Uchida, Naoko; He, Fang; Hashizume, Naotaka

2012-01-01

225

Competition and coexistence of aerobic ammonium- and nitrite-oxidizing bacteria at low oxygen concentrations  

Microsoft Academic Search

In natural and man-made ecosystems nitrifying bacteria experience frequent exposure to oxygen-limited conditions and thus\\u000a have to compete for oxygen. In several reactor systems (retentostat, chemostat and sequencing batch reactors) it was possible\\u000a to establish co-cultures of aerobic ammonium- and nitrite-oxidizing bacteria at very low oxygen concentrations (2–8 ?M) provided\\u000a that ammonium was the limiting N compound. When ammonia was in

A. Olav Sliekers; Suzanne C. M. Haaijer; Marit H. Stafsnes; J. Gijs Kuenen; Mike S. M. Jetten

2005-01-01

226

Application of antimicrobial-producing lactic acid bacteria to control pathogens in ready-to-use vegetables.  

PubMed

Five psychrotrophic strains of lactic acid bacteria (Lactobacillus casei, Lact. plantarum and Pediococcus spp.) were isolated from 22 samples of commercial salads. These strains were shown to inhibit Aeromonas hydrophila, Listeria monocytogenes, Salmonella typhimurium and Staphylococcus aureus on MRS agar, in salads and in juice prepared from vegetable salads. Lactobacillus casei IMPCLC34 was most effective in reducing total mesophilic bacteria and the coliform group; Aer. hydrophila, Salm. typhimurium and Staph. aureus disappeared after 6 d of storage, while the counts for L. monocytogenes remained constant. The potential application of antimicrobial-producing lactic acid bacteria as biopreservatives of ready-to-use vegetables is suggested. PMID:8760320

Vescovo, M; Torriani, S; Orsi, C; Macchiarolo, F; Scolari, G

1996-08-01

227

Imaging of lactic acid bacteria with AFM—elasticity and adhesion maps and their relationship to biological and structural data  

Microsoft Academic Search

The adhesion of lactic acid bacteria to the intestinal epithelium is one of the most important factors determining probiotic ability of a bacterial strain. Studying bacterial adhesion requires knowledge of the structure and properties of the bacterial surface, which can be studied by atomic force microscopy under native conditions. The observation of the surface topography of bacteria from the species

Prisca Schaer-Zammaretti; Job Ubbink

2003-01-01

228

Genome-scale model of Streptococcus thermophilus LMG18311 for metabolic comparison of lactic acid bacteria.  

PubMed

In this report, we describe the amino acid metabolism and amino acid dependency of the dairy bacterium Streptococcus thermophilus LMG18311 and compare them with those of two other characterized lactic acid bacteria, Lactococcus lactis and Lactobacillus plantarum. Through the construction of a genome-scale metabolic model of S. thermophilus, the metabolic differences between the three bacteria were visualized by direct projection on a metabolic map. The comparative analysis revealed the minimal amino acid auxotrophy (only histidine and methionine or cysteine) of S. thermophilus LMG18311 and the broad variety of volatiles produced from amino acids compared to the other two bacteria. It also revealed the limited number of pyruvate branches, forcing this strain to use the homofermentative metabolism for growth optimization. In addition, some industrially relevant features could be identified in S. thermophilus, such as the unique pathway for acetaldehyde (yogurt flavor) production and the absence of a complete pentose phosphate pathway. PMID:19346354

Pastink, Margreet I; Teusink, Bas; Hols, Pascal; Visser, Sanne; de Vos, Willem M; Hugenholtz, Jeroen

2009-04-03

229

Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria  

Microsoft Academic Search

Manned Mars exploration, especially for extended periods of time, will require recycle of materials to support human life. Here, a conceptual design is developed for a Martian agricultural system driven by biologically regenerative functions. One of the core biotechnologies function is the use of hyper-thermophilic aerobic composting bacterial ecology. These thermophilic bacteria can play an important role in increasing the

S. Kanazawa; Y. Ishikawa; K. Tomita-Yokotani; H. Hashimoto; Y. Kitaya; M. Yamashita; M. Nagatomo; T. Oshima; H. Wada

2008-01-01

230

Aerobic biological treatment of olive mill wastewater by olive pulp bacteria  

Microsoft Academic Search

The capability of olive fruit bacteria to remove chemical oxygen demand (COD) and phenolic compounds from olive mill wastewater (OMW) using flasks and packed bed reactors was tested. Batch aerobic experiments were performed in flask reactors, with OMW at different dilutions (20%, 50%, and 100%). The maximum phenolic and dissolved COD removal reached up to 82–90% for the dilutions of

G. Tziotzios; S. Michailakis; D. V. Vayenas

2007-01-01

231

Combined heterotrophic nitrification and aerobic denitrification in Thiosphaera pantotropha and other bacteria  

Microsoft Academic Search

Reports of the simultaneous use of oxygen and denitrification by different species of bacteria have become more common over the past few years. Research with some strains (e.g. Thiosphaera pantotropha) has indicated that there might be a link between this ‘aerobic denitrification’ and a form of nitrification which requires rather than generates energy and is therefore known as heterotrophic nitrification.

Lesley A. Robertson; J. Gijs Kuenen

1990-01-01

232

A Method to Grow Obligately Aerobic Bacteria at Increased Hydrostatic Pressure.  

National Technical Information Service (NTIS)

Culture vessels made of gas-permeable silicone membranes are described in which obligately aerobic bacteria are grown under conditions where mechanical aeration is not possible. The growth of a strain of Pseudomonas putida at 1, 200, and 400 atm is used t...

L. R. Berger L. Q. Tam

1970-01-01

233

Concentrations of butyric acid bacteria spores in silage and relationships with aerobic deterioration  

Microsoft Academic Search

Germination and growth of spores of butyric acid bacteria (BAB) may cause severe defects in semihard cheeses. Silage is the main source of BAB spores in cheese milk. The objectives of the study were to deter- mine the significance of grass silages and corn silages assourcesofBABsporesandtoinvestigatetherelation- ships between high concentrations of BAB spores in corn silage and aerobic deterioration. In

M. M. M. Vissers; F. Driehuis; M. C. Te Giffel; P. De Jong; J. M. G. Lankveld

2007-01-01

234

On the natural selection and evolution of the aerobic phototrophic bacteria  

Microsoft Academic Search

This contribution gives a brief survey of the short history since the discovery of the aerobic phototrophic bacteria to focus on a general evolutionary scenario. Most of the citations are of reviews that have covered the earlier literature and to which the reader is directed at appropriate places in the following text. The data summarized in these reviews are supplemented

J. Thomas Beatty

2002-01-01

235

CHARACTERISTICS OF ALDEHYDE DEHYDROGENASES OF CERTAIN AEROBIC BACTERIA REPRESENTING HUMAN COLONIC FLORA  

Microsoft Academic Search

We have proposed the existence of a bacteriocolonic pathway for ethanol oxidation resulting in high intracolonic levels of toxic and carcinogenic acetaldehyde. This study was aimed at determining the ability of the aldehyde dehydrogenases (ALDH) of aerobic bacteria representing human colonic flora to metabolize intracolonically derived acetaldehyde. The apparent Michaelis constant (Km) values for acetaldehyde were determined in crude extracts

T. NOSOVA; K. JOKELAINEN; P. KAIHOVAARA; R. HEINE; H. JOUSIMIES-SOMER; M. SALASPURO

1998-01-01

236

Aerobic Anoxygenic Photosynthesis in Roseobacter Clade Bacteria from Diverse Marine Habitats  

Microsoft Academic Search

The marine Roseobacter clade comprises several genera of marine bacteria related to the uncultured SAR83 cluster, the second most abundant marine picoplankton lineage. Cultivated representatives of this clade are physiologically heterogeneous, and only some have the capability for aerobic anoxygenic photosynthesis, a process of potentially great ecological importance in the world's oceans. In an attempt to correlate phylogeny with ecology,

Martin Allgaier; Heike Uphoff; Andreas Felske; Irene Wagner-Dobler

2003-01-01

237

Velvet pad surface sampling of anaerobic and aerobic bacteria: an in vitro laboratory model  

Microsoft Academic Search

Velvet pads have been evaluated in an experimental, laboratory model, simulating intraoperative sampling of Staphylococcus epidermis, Escherichia coli and Bacteroides fragilis. After sampling, the pad was placed in a transport medium and kept in an anaerobic atmosphere, before being shaken and rinsed, followed by anaerobic and aerobic culture. This technique permitted quantitatively high recoveries of the test bacteria. Velvet pad

D Raahave; A Friis-Møller

1982-01-01

238

In Silico Evidence for the Horizontal Transfer of gsiB, a ??-Regulated Gene in Gram-Positive Bacteria, to Lactic Acid Bacteria ?  

PubMed Central

gsiB, coding for glucose starvation-inducible protein B, is a characteristic member of the ?? stress regulon of Bacillus subtilis and several other Gram-positive bacteria. Here we provide in silico evidence for the horizontal transfer of gsiB in lactic acid bacteria that are devoid of the ?? factor.

Asteri, Ioanna-Areti; Boutou, Effrossyni; Anastasiou, Rania; Pot, Bruno; Vorgias, Constantinos E.; Tsakalidou, Effie; Papadimitriou, Konstantinos

2011-01-01

239

Bioprotection of Golden Delicious apples and Iceberg lettuce against foodborne bacterial pathogens by lactic acid bacteria.  

PubMed

Lactic acid bacteria were isolated from fresh vegetables and fruit and its ability to inhibit the growth of foodborne human pathogens (Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, and Staphylococcus aureus) was tested using the agar spot assay. Eighteen isolates showed a strong antagonistic capacity and were further characterised and identified using 16S rDNA sequencing and API 50CH. Most of them pertained to Leuconostoc spp. and Lactobacillus plantarum, and a few corresponded to Weissella spp. and Lactococcus lactis. Growth and efficacy of control of foodborne pathogen test bacteria by selected strains were tested in wounded Golden Delicious apples and Iceberg lettuce leaf cuts. The strains grew on the substrates and did not cause negative effects on the general aspect of tissues of apple or lettuce. Treatment of apple wounds and lettuce cuts with the antagonistic strains reduced the cell count of S. typhimurium and E .coli by 1 to 2 log cfu/wound or g, whereas the growth of L. monocytogenes was completely inhibited. Results support the potential use of lactic acid bacteria as bioprotective agents against foodborne human pathogens in ready-to-eat fresh fruit and vegetable products. PMID:18191266

Trias, Rosalia; Bañeras, Lluís; Badosa, Esther; Montesinos, Emilio

2007-12-04

240

Identification of lactic acid bacteria isolated during traditional fura processing in Ghana.  

PubMed

Fura is a millet-based spontaneously fermented dumpling produced and consumed in parts of West Africa, particularly Nigeria, Burkina Faso and Ghana. From eight traditional fura production sites in northern Ghana, 862 lactic acid bacteria were isolated and identified to species level using a combination of genotypic and phenotypic methods including (GTG)(5)-based PCR fingerprinting and 16S rRNA gene sequencing, multiplex PCR by means of recA gene sequence comparison, conventional morphological characteristics and carbohydrate fermentation profiling. During millet dough fermentation, pH decreased from 5.6-6.4 to 4.1-3.7 and total lactic acid bacteria (LAB) counts increased from 4.4-5.3 to 7.9-9.2 log(10) (cfu/g). The initial stages of the fermentation were characterized by co-dominance of homo- and heterofermentative species of Pediococcus acidilactici, Weisella confusa, Lactobacillus fermentum, Lactobacillus reuteri, Lactobacillus salivarius, and Lactobacillus paraplantarum whereas L. fermentum was dominating at the end of the fermentation. L. fermentum was predominant in all fermentations (p < 0.05) and a high uniformity was observed among production sites regarding the dominance of L. fermentum. L. fermentum and W. confusa were isolated in all production sites and almost at all fermentation stages indicating that they are indigenous to traditional fura processing. The other LAB bacteria species which comprised a minor proportion of the total LAB occurred occasionally and in an irregular pattern among the production sites. PMID:22850376

Owusu-Kwarteng, James; Akabanda, Fortune; Nielsen, Dennis S; Tano-Debrah, Kwaku; Glover, Richard L K; Jespersen, Lene

2012-05-11

241

The efficacy of lactic acid bacteria Pediococcus acidilactici, lactose and formic acid as dietary supplements for turkeys.  

PubMed

A feeding trial was performed on 1400 Big-6 turkey toms divided into experimental groups subject to the use of dietary supplements. The ain of this study was to evaluate the efficacy of the probiotic supplement Bactocell, containing lactic acid bacteria Pediococcus acidilactici, and lactose, administered to turkeys separately or in combination, as well as a formic acid supplement. The addition of the probiotic under test (lactic acid bacteria Pediococcus acidilactici) to diets for turkeys contributed to higher daily gains and lower feed consumption per kg weigh gain only during the first 12 weeks of their life. Diet supplementation with lactic acid bacteria and lactose reduced mortality rates. A slaughter value analysis revealed only a slightly (by approximately 1%) higher content of breast muscle and a lower content of thigh muscle in birds fed diets supplemented with lactic acid bacteria. Turkeys receiving lactic acid bacteria or lactose and a combination of both these supplements were characterized by a higher fat content of meat and slightly lower pH values, whereas meat from turkeys fed lactose-supplemented diets was darker in color. The addition of formic acid Acidum formicum to diets for turkeys contributed only to lower mortality rates. PMID:21077430

Wajda, S; Smieci?ska, K; Jankowski, J; Matusevicius, P; Buteikis, G

2010-01-01

242

Identification of lactic acid bacteria isolated from South African brandy base wines.  

PubMed

In brandy base wines, no sulphur dioxide is used and it therefore is ideal for the proliferation of lactic acid bacteria. As part of an extensive taxonomic survey within the ecological framework of South African vineyards and wineries, and the influence of naturally occurring lactic acid bacteria on the quality of wine and brandy, a total of 54 strains were isolated from grape juice and at different stages of brandy base wine production. The strains were identified using numerical analysis of total soluble cell protein patterns, 16S rRNA sequence analyses and polymerase chain reaction (PCR) using species-specific primers. The predominant species was Oenococcus oeni (22 strains), but Lactobacillus brevis (8 strains), Lactobacillus paracasei (8 strains) and Lactobacillus plantarum (6 strains) were also isolated frequently. Many of the O. oeni strains were isolated from brandy base wines after completion of spontaneous malolactic fermentation (MLF). The Lactobacillus spp. were isolated from all the different stages of brandy base wine production. Lb. plantarum was the dominant species in the juice, but disappeared during the later stages of production. However, Lactobacillus hilgardii, Lb. brevis and Lb. paracasei were also isolated from base wine after spontaneous MLF. Strains identified as Lactobacillus vermiforme were isolated during the alcoholic fermentation and after MLF have been completed. Total soluble cell protein patterns grouped O. oeni strains into two phenotypic groups. Two phenotypic clusters have also been identified for the Lb. brevis isolates. The Lb. paracasei isolates all grouped in one cluster. This is the first report of the presence of Lb. paracasei and Lb. vermiforme in brandy base wines. The presence of the Lactobacillus spp. could be correlated to the decrease in quality of the base wine and distillate, while O. oeni strains were found to have a more favourable influence on the quality of base wine and distillates. These results shed some light on the ecology and oenological influence of lactic acid bacteria (LAB) on the quality of South African brandy. PMID:14967557

du Plessis, H W; Dicks, L M T; Pretorius, I S; Lambrechts, M G; du Toit, M

2004-02-15

243

Engineering lactic acid bacteria with pyruvate decarboxylase and alcohol dehydrogenase genes for ethanol production from Zymomonas mobilis  

Microsoft Academic Search

Lactic acid bacteria are candidates for engineered production of ethanol from biomass because they are food-grade microorganisms\\u000a that can, in many cases, metabolize a variety of sugars and grow under harsh conditions. In an effort to divert fermentation\\u000a from production of lactic acid to ethanol, plasmids were constructed to express pyruvate decarboxylase (PDC) and alcohol dehydrogenase\\u000a (ADH), encoded by the

Nancy N. Nichols; Bruce S. Dien; Rodney J. Bothast

2003-01-01

244

Fluorescent protein vectors for promoter analysis in lactic acid bacteria and Escherichia coli.  

PubMed

Fluorescent reporter genes are valuable tools for real-time monitoring of gene expression in living cells. In this study we describe the construction of novel promoter-probe vectors containing a synthetic mCherry fluorescent protein gene, codon-optimized for lactic acid bacteria, divergently linked, or not, to a gene encoding the S65T and F64L variant of the green fluorescent protein. The utility of the transcriptional fusion vectors was demonstrated by the cloning of a single or two divergent promoter regions and by the quantitative evaluation of fluorescence during growth of Lactococcus lactis, Enterococcus faecalis, and Escherichia coli. PMID:22534822

García-Cayuela, Tomás; de Cadiñanos, Luz P Gómez; Mohedano, M Luz; de Palencia, Pilar Fernández; Boden, Daniel; Wells, Jerry; Peláez, Carmen; López, Paloma; Requena, Teresa

2012-04-27

245

Two distinct pathways for the formation of hydroxy FA from linoleic acid by lactic acid bacteria  

Microsoft Academic Search

Twenty-three of 86 strains of lactic acid bacteria transformed linoleic acid into hydroxy FA. Two distinct conversion pathways\\u000a were in operation. Two strains of Lactobacillus acidophilus and a strain of Pediococcus pentosaceus produced 13(S)-hydroxy-9-octadecenoic acid [13(S)-OH 18?1] and 10,13-dihydroxyoctadecanoic acid (10,13-OH 18?0) as main and minor products, respectively, whereas 13 strains,\\u000a including L. casei subsp. casei, L. paracasei subsp, paracasei,

Noriaki Kishimoto; Izumi Yamamoto; Kazuki Toraishi; Satiko Yoshioka; Kenji Saito; Hideki Masuda; Tokio Fujita

2003-01-01

246

Bacteriocin-Producing Lactic Acid Bacteria Isolated from Traditional Fermented Food  

PubMed Central

Lactic Acid Bacteria (LAB) isolated from several traditional fermented foods such as “tempeh”, “tempoyak” and “tapai” were screened for the production of bacteriocin. One strain isolated from “tempeh” gives an inhibitory activity against several LAB. The strain was later identified as Lactobacillus plantarum BS2. Study shows that the inhibitory activity was not caused by hydrogen peroxide, organic acids or bacteriophage. The bacteriocin production was maximum after 10 hours of incubation with an activity of 200 AU/ml. The bacteriocin was found to be sensitive towards trypsin, ?-chymotrypsin, ?-chymotrypsin, ?-amylase and lysozyme.

Kormin, Salasiah; Rusul, Gulam; Radu, Son; Ling, Foo Hooi

2001-01-01

247

Perspectives on the contribution of lactic acid bacteria to cheese flavor development.  

PubMed

It has been known since the 1960s that lactic acid bacteria are essential for the development of cheese flavor. In the ensuing 50 years significant research has been directed at understanding the microbiology, genetics and biochemistry of this process. This review briefly covers the current status of cheese flavor development and then provides our vision for approaches which will enhance our understanding of this process. The long-term goal of this area of research is to enable technology (i.e. cultures and enzymes) that results in consistent rapid development of cheese variety-specific characteristic flavors. PMID:23279928

Steele, James; Broadbent, Jeffery; Kok, Jan

2012-12-29

248

Production of ?-Amino Butyric Acid in Tea Leaves wit Treatment of Lactic Acid Bacteria  

NASA Astrophysics Data System (ADS)

Lactic acid bacteria was searched for producing termented tea that contained a lot of ?-amino butyric acid(GABA). Also examined were the growth condition, GABA production and changes in catechin contents in the tea leaves. Lactobacillus brevis L12 was found to be suitable for the production of fermented tea since it gave as much GABA as gabaron tea when tea leaves being suspended with water at 10% and incubated for 4 days at 25°C. The amount of GABA produced was more than calculated based upon the content of glutamic acid in tea leaves. It is probable to assume that glutamate derived from glutamine and theanine is converted into GABA.

Watanabe, Yuko; Hayakawa, Kiyoshi; Ueno, Hiroshi

249

Fate of Chlortetracycline and Tylosin-Resistant Bacteria in an Aerobic Thermophilic Sequencing Batch Reactor Treating Swine Waste  

Microsoft Academic Search

Antibiotics have been added to animal feed for decades. Consequently, food animals and their wastes constitute a reservoir\\u000a of antibiotic-resistant bacteria. The objective of this work was to characterize the impact of an aerobic thermophilic biotreatment\\u000a on aerobic, antibiotic-resistant bacteria in swine waste. The proportion of tylosin- and chlortetracycline-resistant bacteria\\u000a grown at 25°C, 37°C, and 60°C decreased after treatment, but

Martin R. Chénier; Pierre Juteau

2009-01-01

250

Interaction of lactic acid bacteria with metal ions: opportunities for improving food safety and quality.  

PubMed

Certain species of lactic acid bacteria (LAB), as well as other microorganisms, can bind metal ions to their cells surface or transport and store them inside the cell. Due to this fact, over the past few years interactions of metal ions with LAB have been intensively investigated in order to develop the usage of these bacteria in new biotechnology processes in addition to their health and probiotic aspects. Preliminary studies in model aqueous solutions yielded LAB with high absorption potential for toxic and essential metal ions, which can be used for improving food safety and quality. This paper provides an overview of results obtained by LAB application in toxic metal ions removing from drinking water, food and human body, as well as production of functional foods and nutraceutics. The biosorption abilities of LAB towards metal ions are emphasized. The binding mechanisms, as well as the parameters influencing the passive and active uptake are analyzed. PMID:22806724

Mrv?i?, Jasna; Stanzer, Damir; Soli?, Ema; Stehlik-Tomas, Vesna

2012-06-14

251

Anti-diabetic effects of lactic acid bacteria in normal and type 2 diabetic mice.  

PubMed

The antidiabetic effects of lactic acid bacteria were investigated using mice. In Experiment 1, normal ICR mice were loaded with sucrose or starch with or without viable Lactobacillus rhamnosus GG cells. GG significantly inhibited postprandial blood glucose levels when administered with sucrose or starch. In Experiment 2, KK-A(y) mice, a model of genetic type 2 diabetes, were given a basal diet containing viable GG cells or viable Lactobacillus delbrueckii subsp. bulgaricus cells for 6 weeks. Viable GG cells significantly inhibited fasting blood glucose, postprandial blood glucose in a glucose tolerance test and HbA1c. Such effects were not shown by viable L. bulgaricus cells. In Experiment 3, the KK-A(y) mice were given a basal diet containing viable GG cells or heat-treated GG cells for 3 weeks. The viable GG cells significantly suppressed fasting blood glucose and impaired glucose tolerance, but the heat-treated GG showed no effects. These results demonstrated that GG decreased the postprandial blood glucose in ICR mice, and that the antidiabetic activity of lactic acid bacteria on the KK-A(y) mice differed depending on the bacterial strain and whether the bacterium is viable when it arrives in the intestine. In the present study, we conclude that the antidiabetic activity may result from continuous inhibition of the postprandial blood glucose through suppression of glucose absorption from the intestine. These findings indicate that specific strains of lactic acid bacterium can be expected to be beneficial for the management of type 2 diabetes. PMID:22962525

Honda, Kayoko; Moto, Mihoko; Uchida, Naoko; He, Fang; Hashizume, Naotaka

2012-07-30

252

Natural populations of lactic acid bacteria isolated from vegetable residues and silage fermentation.  

PubMed

Natural populations of lactic acid bacteria (LAB) and silage fermentation of vegetable residues were studied. Fifty-two strains of LAB isolated from cabbage, Chinese cabbage, and lettuce residues were identified and characterized. The LAB strains were gram-positive and catalase-negative bacteria, which were divided into 6 groups (A to F) according to morphological and biochemical characteristics. The strains in group A were rods that did not produce gas from glucose and formed the d and l isomers of lactate. Groups B and C were homofermentative cocci that formed l-lactic acid. Groups D, E, and F were heterofermentative cocci that formed d-lactic acid. Based on 16S rDNA gene sequence analysis, group A to F strains were identified as Lactobacillus plantarum, Lactococcus piscium, Lactococcus lactis, Leuconostoc citreum, Weissella soli and Leuconostoc gelidum, respectively. The prevalent LAB, predominantly homofermentative lactobacilli, consisted of Lactobacillus plantarum (34.6%), Weissella soli (19.2%), Leuconostoc gelidum (15.4%), Leuconostoc citreum (13.5%), Lactococcus lactis (9.6%), and Lactococcus piscium (7.7%). Lactobacillus plantarum was the dominant member of the LAB population in 3 types of vegetable residues. These vegetable residues contained a high level of crude protein (20.2 to 28.4% of dry matter). These silages prepared by using a small-scale fermentation system were well preserved, with low pH and a relatively high content of lactate. This study suggests that the vegetable residues contain abundant LAB species and nutrients, and that they could be well preserved by making silage, which is a potentially good vegetable protein source for livestock diets. PMID:20630231

Yang, J; Cao, Y; Cai, Y; Terada, F

2010-07-01

253

Technological and functional applications of low-calorie sweeteners from lactic acid bacteria.  

PubMed

Lactic acid bacteria (LAB) have been extensively used for centuries as starter cultures to carry out food fermentations and are looked upon as burgeoning "cell factories" for production of host of functional biomolecules and food ingredients. Low-calorie sugars have been a recent addition and have attracted a great deal of interest of researchers, manufacturers, and consumers for varied reasons. These sweeteners also getting popularized as low-carb sugars have been granted generally recommended as safe (GRAS) status by the U.S. Federal Drug Administration (USFDA) and include both sugars and sugar alcohols (polyols) which in addition to their technological attributes (sugar replacer, bulking agent, texturiser, humectant, cryoprotectant) have been observed to exert a number of health benefits (low calories, low glycemic index, anticariogenic, osmotic diuretics, obesity control, prebiotic). Some of these sweeteners successfully produced by lactic acid bacteria include mannitol, sorbitol, tagatose, and trehalose and there is a potential to further enhance their production with the help of metabolic engineering. These safe sweeteners can be exploited as vital food ingredients for development of low-calorie foods with added functional values especially for children, diabetic patients, and weight watchers. PMID:19200114

Patra, F; Tomar, S K; Arora, S

254

Cell membrane damage induced by phenolic acids on wine lactic acid bacteria.  

PubMed

The aim of this work was to investigate the effect of phenolic acids on cell membrane permeability of lactic acid bacteria from wine. Several phenolic acids were tested for their effects on the cell membrane of Oenococcus oeni and Lactobacillus hilgardii by measuring potassium and phosphate efflux, proton influx and by assessing culture viability employing a fluorescence technique based on membrane integrity. The experimental results indicate that hydroxycinnamic acids (p-coumaric, caffeic and ferulic acids) induce greater ion leakages and higher proton influx than hydroxybenzoic acids (p-hydroxibenzoic, protocatechuic, gallic, vanillic, and syringic acids). Among the hydroxycinnamic acids, p-coumaric acid showed the strongest effect. Moreover, the exposure of cells to phenolic acids caused a significant decrease in cell culture viability, as measured by the fluorescence assay, in both tested strains. The results agree with previous results obtained in growth experiments with the same strains. Generally, phenolic acids increased the cell membrane permeability in lactic acid bacteria from wine. The different effects of phenolic acids on membrane permeability could be related to differences in their structure and lipophilic character. PMID:19733929

Campos, F M; Couto, J A; Figueiredo, A R; Tóth, I V; Rangel, A O S S; Hogg, T A

2009-08-04

255

Selected lactic acid bacteria synthesize antioxidant peptides during sourdough fermentation of cereal flours.  

PubMed

A pool of selected lactic acid bacteria was used for the sourdough fermentation of various cereal flours with the aim of synthesizing antioxidant peptides. The radical-scavenging activity of water/salt-soluble extracts (WSE) from sourdoughs was significantly (P < 0.05) higher than that of chemically acidified doughs. The highest activity was found for whole wheat, spelt, rye, and kamut sourdoughs. Almost the same results were found for the inhibition of linoleic acid autoxidation. WSE were subjected to reverse-phase fast protein liquid chromatography. Thirty-seven fractions were collected and assayed in vitro. The most active fractions were resistant to further hydrolysis by digestive enzymes. Twenty-five peptides of 8 to 57 amino acid residues were identified by nano-liquid chromatography-electrospray ionization-tandem mass spectrometry. Almost all of the sequences shared compositional features which are typical of antioxidant peptides. All of the purified fractions showed ex vivo antioxidant activity on mouse fibroblasts artificially subjected to oxidative stress. This study demonstrates the capacity of sourdough lactic acid bacteria to release peptides with antioxidant activity through the proteolysis of native cereal proteins. PMID:22156436

Coda, Rossana; Rizzello, Carlo Giuseppe; Pinto, Daniela; Gobbetti, Marco

2011-12-09

256

Improved screening procedure for biogenic amine production by lactic acid bacteria.  

PubMed

An improved screening plate method for the detection of amino acid decarboxylase-positive microorganisms (especially lactic acid bacteria) was developed. The suitability and detection level of the designed medium were quantitatively evaluated by confirmation of amine-forming capacity using an HPLC procedure. The potential to produce the biogenic amines (BA) tyramine, histamine, putrescine, and cadaverine, was investigated in a wide number of lactic acid bacteria (LAB) of different origin, including starter cultures, protective cultures, type strains and strains isolated from different food products. Also, several strains of Enterobacteriaceae were examined. Modifications to previously described methods included lowering glucose and sodium chloride concentrations, and increasing the buffer effect with calcium carbonate and potassium phosphate. In addition, pyridoxal-5-phosphate was included as a codecarboxylase factor for its enhancing effect on the amino acid decarboxylase activity. The screening plate method showed a good correlation with the chemical analysis and due to its simplicity it is presented as a suitable and sensitive method to investigate the capacity of biogenic amine production by LAB. Tyramine was the main amine formed by the LAB strains investigated. Enterococci, carnobacteria and some strains of lactobacilli, particularly of Lb. curvatus. Lb. brevis and Lb. buchneri, were the most intensive tyramine formers. Several strains of lactobacilli, Leuconostoc spp., Weissella spp. and pediococci did not show any potential to produce amines. Enterobacteriaceae were associated with cadaverine and putrescine formation. No significant histamine production could be detected for any of the strains tested. PMID:10598112

Bover-Cid, S; Holzapfel, W H

1999-12-01

257

Rapid identification of lactic acid bacteria isolated from home-made fermented milk in Tibet.  

PubMed

Fermented milk is a very delicious and nutritional food distributed in the international markets. Rapid preliminary identification of lactic acid bacteria to the species level is an important issue for the fermentation industry. One hundred seventy-one strains of lactic acid bacteria (LAB) were isolated from twenty-nine kurut samples and fifteen traditional fermented mongolian cattle milk (FMCM) samples in Tibet, China. All of the strains were isolated and divided into bacilli or cocci by phenotype, and then differentiated by restriction fragment length polymorphism (RFLP) analysis using a set of restriction enzymes, AluI, HaeIII, BsmaI, TspRI and HinfI. Restriction pattern analyses indicated that the lactobacilli could be clearly identified at the species level and the LAB cocci at the genera level by the five restriction enzymes. Further studies on 16S rDNA sequences of representative and undefined strains showed that the combination of RFLP analysis of polymerase chain reaction (PCR) for amplifying 16S rDNA and 16S rDNA sequence analysis is rapid, easy to perform, and effective for large-scale preliminary identification of LAB. PMID:19590145

Yu, Jie; Sun, Zhihong; Liu, Wenjun; Zhang, Jiachao; Sun, Tiansong; Bao, Qiuhua; Zhang, Heping

2009-06-01

258

Prediction of acid lactic-bacteria growth in turkey ham processed by high hydrostatic pressure  

PubMed Central

High hydrostatic pressure (HHP) has been investigated and industrially applied to extend shelf life of meat-based products. Traditional ham packaged under microaerophilic conditions may sometimes present high lactic acid bacteria population during refrigerated storage, which limits shelf life due to development of unpleasant odor and greenish and sticky appearance. This study aimed at evaluating the shelf life of turkey ham pressurized at 400 MPa for 15 min and stored at 4, 8 and 12 °C, in comparison to the non pressurized product. The lactic acid bacteria population up to 107 CFU/g of product was set as the criteria to determine the limiting shelf life According to such parameter the pressurized sample achieved a commercial viability within 75 days when stored at 4 °C while the control lasted only 45 days. Predictive microbiology using Gompertz and Baranyi and Roberts models fitted well both for the pressurized and control samples. The results indicated that the high hydrostatic pressure treatment greatly increased the turkey ham commercial viability in comparison to the usual length, by slowing down the growth of microorganisms in the product.

Mathias, S.P.; Rosenthal, A.; Gaspar, A.; Aragao, G.M.F.; Slongo-Marcusi, A.

2013-01-01

259

Antimicrobial interactions of microbial species involved in the fermentation of cassava dough into agbelima with particular reference to the inhibitory effect of lactic acid bacteria on enteric pathogens  

Microsoft Academic Search

Lactic acid bacteria, Bacillus species and yeasts are involved in the fermentation of cassava dough into agbelima. Microbial interactions within and between these groups of microorganisms were investigated in addition to the survival of five enteric pathogens inoculated into agbelima under various conditions. Nine out of 10 cultures of lactic acid bacteria isolated at the end of agbelima fermentation showed

Ebenezer Siaw Mante; Esther Sakyi-Dawson; Wisdom Kofi Amoa-Awua

2003-01-01

260

Preservation of acidified cucumbers with a natural preservative combination of fumaric acid and allyl isothiocyanate that target lactic acid bacteria and yeasts  

Technology Transfer Automated Retrieval System (TEKTRAN)

Without the addition of preservative compounds cucumbers acidified with 150 mM acetic acid with pH adjusted to 3.5 typically undergo fermentation by lactic acid bacteria. Fumaric acid (20 mM) inhibited growth of Lactobacillus plantarum and the lactic acid bacteria present on fresh cucumbers, but sp...

261

Characterization of abundance and diversity of lactic acid bacteria in the hindgut of wood- and soil-feeding termites by molecular and culture-dependent techniques  

Microsoft Academic Search

Lactic acid bacteria have been identified as typical and numerically significant members of the gut microbiota of Reticulitermes flavipes and other wood-feeding lower termites. We found that also in the guts of the higher termites Nasutitermes arborum (wood-feeding), Thoracotermes macrothorax, and Anoplotermes pacificus (both soil-feeding), lactic acid bacteria represent the largest group of culturable carbohydrate-utilizing bacteria (3.6-5.2쎸 bacteria per gut;

Sabine Bauer; Anne Tholen; Jörg Overmann; Andreas Brune

2000-01-01

262

Total mesophilic counts underestimate in many cases the contamination levels of psychrotrophic lactic acid bacteria (LAB) in chilled-stored food products at the end of their shelf-life.  

PubMed

The major objective of this study was to determine the role of psychrotrophic lactic acid bacteria (LAB) in spoilage-associated phenomena at the end of the shelf-life of 86 various packaged (air, vacuum, modified-atmosphere) chilled-stored retail food products. The current microbiological standards, which are largely based on the total viable mesophilic counts lack discriminatory capacity to detect psychrotrophic LAB. A comparison between the total viable counts on plates incubated at 30 °C (representing the mesophiles) and at 22 °C (indicating the psychrotrophs) for 86 food samples covering a wide range - ready-to-eat vegetable salads, fresh raw meat, cooked meat products and composite food - showed that a consistent underestimation of the microbial load occurs when the total aerobic mesophilic counts are used as a shelf-life parameter. In 38% of the samples, the psychrotrophic counts had significantly higher values (+0.5-3 log CFU/g) than the corresponding total aerobic mesophilic counts. A total of 154 lactic acid bacteria, which were unable to proliferate at 30 °C were isolated. In addition, a further 43 with a poor recovery at this temperature were also isolated. This study highlights the potential fallacy of the total aerobic mesophilic count as a reference shelf-life parameter for chilled food products as it can often underestimate the contamination levels at the end of the shelf-life. PMID:22986212

Pothakos, Vasileios; Samapundo, Simbarashe; Devlieghere, Frank

2012-08-07

263

[Resistance to chemotherapy of aerobic bacteria from nonspecific odontogenic infections].  

PubMed

Germs in patients suffering from nonspecific odontogenous infections described in a previous paper were analysed with regard to their resistance to chemotherapy (1964 to 1971). At the same time it was discovered that in the bacteria groups: staphyloccocus aureus, streptococci and pneumococci and enterobacteriaceae plus pseudomonas (344 strains) their sensitivity to penicillin, streptomycin, chloramphenicol, oxytetracyclin, erythromycin, polymyxin B and nifurantin varied in several and significant ways. Significant changes were established in the resistance of staphylococcus aureus to all the potentially effective antibiotics, while from 1969 to 1971 the strains with the least resistance appeared. In the 1970 to 1971 period strepto- and pneumococci showed insensitivity to penicillin and streptomycin more frequently than before. From 1969 to 1971 entero-bacteriaceae and pseudomonas also showed evidence of increasing loss of sensitivity to chloramphenicol and oxytetracyclin, whereas the frequency of strains resistant to polymyxin B and nifurantine diminished. The findings are being discussed. PMID:188271

Oehring, H; Schumann, D; Karl, P; Knappe, U; Gruhn, I

1976-01-01

264

Rapid High-Throughput Assessment of Aerobic Bacteria in Complex Samples by Fluorescence-Based Oxygen Respirometry  

Microsoft Academic Search

A simple method has been developed for the analysis of aerobic bacteria in complex samples such as broth and food homogenates. It employs commercial phosphorescent oxygen-sensitive probes to monitor oxygen consumption of samples containing bacteria using standard microtiter plates and fluorescence plate readers. As bacteria grow in aqueous medium, at certain points they begin to deplete dissolved oxygen, which is

Fiach C. O'Mahony; Dmitri B. Papkovsky

2006-01-01

265

[Screening and denitrification characteristics of a heterotrophic nitrification-aerobic denitrifier bacteria].  

PubMed

A heterotrophic nitrification-aerobic denitrifier bacteria CPZ24 was isolated form the livestock wastewater by way of the limiting dilution combined with the chromogenic medium screening methods. This bacterium was Gram positive, rod. The colonies of the strain were orange-red.It was identified as Rhodococuus pyridinivorans according to its morphological and physiological properties and the analysis of its 16S rDNA gene. Studied on its function of heterotrophic nitrification and aerobic denitrification,the results show that all NH4+ -N is removed and the removal rate of TN is 98.70% in heterotrophic nitrification; the removal rate of NO3- -N by this strain is 66.74% and the removal rate of TN is 64.27%. This high effective microorganisms with nitrogen removed is able to realize simultaneous nitrification and denitrification. It can perform the whole process of bacteria denitrification independently. PMID:20187396

Chen, Pei-zhen; Wang, Li-gang; Wang, Ying-chun; Li, Ji; Ding, Wei; Ren, Tian-zhi; Li, Shao-peng

2009-12-01

266

Aerobic Anoxygenic Phototrophic Bacteria in the Mid-Atlantic Bight and the North Pacific Gyre  

PubMed Central

The abundance of aerobic anoxygenic phototrophic (AAP) bacteria, cyanobacteria, and heterotrophs was examined in the Mid-Atlantic Bight and the central North Pacific Gyre using infrared fluorescence microscopy coupled with image analysis and flow cytometry. AAP bacteria comprised 5% to 16% of total prokaryotes in the Atlantic Ocean but only 5% or less in the Pacific Ocean. In the Atlantic, AAP bacterial abundance was as much as 2-fold higher than that of Prochlorococcus spp. and 10-fold higher than that of Synechococcus spp. In contrast, Prochlorococcus spp. outnumbered AAP bacteria 5- to 50-fold in the Pacific. In both oceans, subsurface abundance maxima occurred within the photic zone, and AAP bacteria were least abundant below the 1% light depth. The abundance of AAP bacteria rivaled some groups of strictly heterotrophic bacteria and was often higher than the abundance of known AAP bacterial genera (Erythrobacter and Roseobacter spp.). Concentrations of bacteriochlorophyll a (BChl a) were low (?1%) compared to those of chlorophyll a in the North Atlantic. Although the BChl a content of AAP bacteria per cell was typically 20- to 250-fold lower than the divinyl-chlorophyll a content of Prochlorococcus, the pigment content of AAP bacteria approached that of Prochlorococcus in shelf break water. Our results suggest that AAP bacteria can be quite abundant in some oceanic regimes and that their distribution in the water column is consistent with phototrophy.

Cottrell, Matthew T.; Mannino, Antonio; Kirchman, David L.

2006-01-01

267

[Viability and activity of the lactic bacteria (Streptococcus salivarius ssp thermophilus y Lactobacillus delbrueckii ssp bulgaricus) del yogurt en Venezuela].  

PubMed

National and international legislations have agreed that the population of lactic bacteria in yogurt must be viable and not less than 10(6) ufc/g. In Venezuela, during last years, observations indicate that the number of viable cells in some commercial samples show high variations, as low levels. This research attempted to find the origin of this problem in the local industry. For this purpose 105 commercial samples were analyzed during their shelf life and 32 samples of yogurt prepared in the laboratory following the flow diagram of the local industry. The different conditions of freeze dried lactic culture, were also analyzed. These samples were evaluated for viable cell count of lactic bacteria and possible variations of pH and acidity. The absence or low number of lactic bacteria detected in some commercial samples is due to the use of inadequate working cultures that show imbalanced proportions of the two microorganisms, besides a low count below 106 ufc/g. The succesive propagation and storage time of mother culture, and the overacidification of the product, produce subletal injury to the microbial cells of the yogurt starter culture. The data indicate that manufacturing practices significantly affect the survival of the lactic flora. PMID:11510428

Briceño, A G; Martínez, R; García, K

2001-01-01

268

Current status and emerging role of glutathione in food grade lactic acid bacteria  

PubMed Central

Lactic acid bacteria (LAB) have taken centre stage in perspectives of modern fermented food industry and probiotic based therapeutics. These bacteria encounter various stress conditions during industrial processing or in the gastrointestinal environment. Such conditions are overcome by complex molecular assemblies capable of synthesizing and/or metabolizing molecules that play a specific role in stress adaptation. Thiols are important class of molecules which contribute towards stress management in cell. Glutathione, a low molecular weight thiol antioxidant distributed widely in eukaryotes and Gram negative organisms, is present sporadically in Gram positive bacteria. However, new insights on its occurrence and role in the latter group are coming to light. Some LAB and closely related Gram positive organisms are proposed to possess glutathione synthesis and/or utilization machinery. Also, supplementation of glutathione in food grade LAB is gaining attention for its role in stress protection and as a nutrient and sulfur source. Owing to the immense benefits of glutathione, its release by probiotic bacteria could also find important applications in health improvement. This review presents our current understanding about the status of glutathione and its role as an exogenously added molecule in food grade LAB and closely related organisms.

2012-01-01

269

Incidence of Bacteriocins Produced by Food-Related Lactic Acid Bacteria Active towards Oral Pathogens  

PubMed Central

In the present study we investigated the incidence of bacteriocins produced by 236 lactic acid bacteria (LAB) food isolates against pathogenic or opportunistic pathogenic oral bacteria. This set of LAB contained several strains (?17%) producing bacteriocins active against food-related bacteria. Interestingly only Streptococcus macedonicus ACA-DC 198 was able to inhibit the growth of Streptococcus oralis, Streptococcus sanguinis and Streptococcus gordonii, while Lactobacillus fermentum ACA-DC 179 and Lactobacillus plantarun ACA-DC 269 produced bacteriocins solely against Streptococcus oralis. Thus, the percentage of strains that were found to produce bacteriocins against oral bacteria was ~1.3%. The rarity of bacteriocins active against oral LAB pathogens produced by food-related LAB was unexpected given their close phylogenetic relationship. Nevertheless, when tested in inhibition assays, the potency of the bacteriocin(s) of S. macedonicus ACA-DC 198 against the three oral streptococci was high. Fourier-transform infrared spectroscopy combined with principal component analysis revealed that exposure of the target cells to the antimicrobial compounds caused major alterations of key cellular constituents. Our findings indicate that bacteriocins produced by food-related LAB against oral LAB may be rare, but deserve further investigation since, when discovered, they can be effective antimicrobials.

Zoumpopoulou, Georgia; Pepelassi, Eudoxie; Papaioannou, William; Georgalaki, Marina; Maragkoudakis, Petros A.; Tarantilis, Petros A.; Polissiou, Moschos; Tsakalidou, Effie; Papadimitriou, Konstantinos

2013-01-01

270

Aerobic growth of campylobacter in media supplemented with glutamic, lactic, and/or fumaric acids  

Technology Transfer Automated Retrieval System (TEKTRAN)

Campylobacter spp. are major causes of human foodborne illnesses, and the pathogen is widely associated with live poultry and processed poultry products. These bacteria are classified as obligate microaerophiles and are generally cultured under atmospheres with reduced oxygen and elevated carbon dio...

271

Genome Analysis of Food Grade Lactic Acid-Producing Bacteria: From Basics to Applications  

PubMed Central

Whole-genome sequencing has revolutionized and accelerated scientific research that aims to study the genetics, biochemistry and molecular biology of bacteria. Lactic acid-producing bacteria, which include lactic acid bacteria (LAB) and bifidobacteria, are typically Gram-positive, catalase-negative organisms, which occupy a wide range of natural plant- and animal-associated environments. LAB species are frequently involved in the transformation of perishable raw materials into more stable, pleasant, palatable and safe fermented food products. LAB and bifidobacteria are also found among the resident microbiota of the gastrointestinal and/or genitourinary tracts of vertebrates, where they are believed to exert health-promoting effects. At present, the genomes of more than 20 LAB and bifidobacterial species have been completely sequenced. Their genome content reflects its specific metabolism, physiology, biosynthetic capabilities, and adaptability to varying conditions and environments. The typical LAB/bifidobacterial genome is relatively small (from 1.7 to 3.3 Mb) and thus harbors a limited assortment of genes (from around 1,600 to over 3,000). These small genomes code for a broad array of transporters for efficient carbon and nitrogen assimilation from the nutritionally-rich niches they usually inhabit, and specify a rather limited range of biosynthetic and degrading capabilities. The variation in the number of genes suggests that the genome evolution of each of these bacterial groups involved the processes of extensive gene loss from their particular ancestor, diversification of certain common biological activities through gene duplication, and acquisition of key functions via horizontal gene transfer. The availability of genome sequences is expected to revolutionize the exploitation of the metabolic potential of LAB and bifidobacteria, improving their use in bioprocessing and their utilization in biotechnological and health-related applications.

Mayo, B; van Sinderen, D; Ventura, M

2008-01-01

272

Interaction between lactic acid bacteria and gastrointestinal nematodes of caprine origin.  

PubMed

To compare the level of parasitism with gastrointestinal nematodes in sheep and goats, several studies have been conducted. They have generally shown that goats were more infected than sheep, as they exhibited higher worm burdens and egg excretion. This difference between two host species has been attributed not only to a difference in feeding behavior, but also to a lesser ability of goats to develop resistance to trichostrongylate infection (In kids and lambs the greatest damage is observed from weaning until 1 yr of age; mature mothers, before and after parturition and during suckling, are affected). In the last few decades, the most common tool (and frequently the only one) used for controlling internal parasites in livestock was the anthelmintic drugs. The application of anthelmintic treatments; must be accompanied by epidemic data and determinations supporting the appropriate timing and frequency of animal treatment. This view has not always been respected. In our country, because of a decrease in price, the anthelmintic drugs were used indiscriminately, causing the resistance we see today. This serious problem, added to the objective of producing organic foods without drug residuals, calls for better use of the antiparasitic drugs and for the developmentment of alternative methods that are ecologically viable and without risks for human health.Little information is available on the interactions between bacteria and intestinal nematodes of caprine origin. Some reports note ovicidal activity of different strains of Bacillus thuringiensis on the eggs of zooparasitic nematodes. Recent work found inhibitory actions of lactic bacteria on gastrointestinal nematodes (both of caprine origin). In the present chapter we describe the methods used for the determination of interactions between lactic acid bacteria and nematodes. PMID:15156032

Draksler, Diana; Monferran, María Cecilia; González, Silvia

2004-01-01

273

Phylogenetic diversity and activity of aerobic heterotrophic bacteria from a hypersaline oil-polluted microbial mat  

Microsoft Academic Search

The diversity and function of aerobic heterotrophic bacteria (AHB) in cyanobacterial mats have been largely overlooked. We used culture-dependent and molecular techniques to explore the species diversity, degradative capacities and functional guilds of AHB in the photic layer (2mm) of an oil-polluted microbial mat from Saudi Arabia. Enrichment isolation was carried out at different salinities (5% and 12%) and temperatures

Raeid M. M. Abed; Burhanuddin Zein; Assad Al-Thukair; Dirk de Beer

2007-01-01

274

Inhibition of Human Immunodeficiency Virus Type 1 by Lactic Acid Bacteria from Human Breastmilk  

PubMed Central

Abstract Background Human breastmilk provides a rich source of commensal lactic acid bacteria (LAB) to the infant during breastfeeding and stimulates abundant growth and colonization of these bacteria at mucosal surfaces in the infant gastrointestinal tract. While conferring critical nutritional and immunologic support to the developing newborn, breastmilk also serves as a vehicle for human immunodeficiency virus type 1 (HIV-1) transmission from mother to child during breastfeeding. Whether breastmilk LAB confer protection against mucosal exposure to HIV-1 in breastfeeding infants is unknown. Study Design In the present study, we sought to evaluate LAB isolated from the breastmilk of healthy women for the ability to inhibit HIV-1 infection in vitro. A total of 38 strains of breastmilk bacteria were evaluated in this study. Both heat-killed bacteria and cell-free conditioned supernatants from bacterial cultures were tested for the ability to inhibit infection with HIV-1 using viral isolates with tropism for CCR5 (R5), CXCR4 (X4), or R5/X4 dual-tropism. Results Significant inhibition of R5-tropic HIV-1 was demonstrated using heat-killed bacteria, most notably among breastmilk strains of Lactobacillus and Pediococcus. Selected strains of breastmilk LAB also demonstrated significant inhibition of HIV-1 infection against virus with tropism for X4 and R5/X4. Conclusion These results demonstrate for the first time that commensal LAB from human breastmilk inhibit HIV-1 infection in vitro and suggest a possible role for these bacteria in mucosal protection against HIV-1 in the breastfeeding infant.

Martin, Virginia; Maldonado, Antonio; Fernandez, Leonides; Rodriguez, Juan M.

2010-01-01

275

Aerobic anoxygenic phototrophic bacteria attached to particles in turbid waters of the Delaware and Chesapeake estuaries.  

PubMed

Aerobic anoxygenic phototrophic (AAP) bacteria are photoheterotrophs that, if abundant, may be biogeochemically important in the oceans. We used epifluorescence microscopy and quantitative PCR (qPCR) to examine the abundance of these bacteria by enumerating cells with bacteriochlorophyll a (bChl a) and the light-reaction center gene pufM, respectively. In the surface waters of the Delaware estuary, AAP bacteria were abundant, comprising up to 34% of prokaryotes, although the percentage varied greatly with location and season. On average, AAP bacteria made up 12% of the community as measured by microscopy and 17% by qPCR. In the surface waters of the Chesapeake, AAP bacteria were less abundant, averaging 6% of prokaryotes. AAP bacterial abundance was significantly correlated with light attenuation (r=0.50) and ammonium (r=0.42) and nitrate (r=0.71) concentrations. Often, bChl a-containing bacteria were mostly attached to particles (31 to 94% of total AAP bacteria), while usually 20% or less of total prokaryotes were associated with particles. Of the cells containing pufM, up to 87% were associated with particles, but the overall average of particle-attached cells was 15%. These data suggest that AAP bacteria are particularly competitive in these two estuaries, in part due to attachment to particles. PMID:17468276

Waidner, Lisa A; Kirchman, David L

2007-04-27

276

Growth-inhibition of hiochi bacteria in namazake (raw sake) by bacteriocins from lactic acid bacteria  

Microsoft Academic Search

The bacteriocins produced by Lactococcus lactis subsp. lactis C101910 (C101910) and NBRC 12007 (NBRC 12007) were used to prevent the growth of sake spoiling hiochi bacteria (Lactobacillus hilgardii, Lactobacillus fructivorans, and Lactobacillus paracasei) in namazake, which is raw (unpasteurized) sake. The bacteriocin concentrations required for decreasing the viable cell concentrations of L. hilgardii and L. fructivorans below the detection limit

Masayuki Taniguchi; Yohei Ishiyama; Takeomi Takata; Toshihiro Nakanishi; Mitsuoki Kaneoke; Ken-ichi Watanabe; Fujitoshi Yanagida; Yi-sheng Chen; Tomoaki Kouya; Takaaki Tanaka

2010-01-01

277

Influence of Geographical Origin and Flour Type on Diversity of Lactic Acid Bacteria in Traditional Belgian Sourdoughs  

Microsoft Academic Search

A culture-based approach was used to investigate the diversity of lactic acid bacteria (LAB) in Belgian traditional sourdoughs and to assess the influence of flour type, bakery environment, geographical origin, and technological characteristics on the taxonomic composition of these LAB communities. For this purpose, a total of 714 LAB from 21 sourdoughs sampled at 11 artisan bakeries throughout Belgium were

Ilse Scheirlinck; Roel Van der Meulen; Ann Van Schoor; Marc Vancanneyt; Luc De Vuyst; Peter Vandamme; Geert Huys

2007-01-01

278

Tina wooden vat biofilm: A safe and highly efficient lactic acid bacteria delivering system in PDO Ragusano cheese making  

Microsoft Academic Search

In the Sicilian PDO Ragusano cheese making, raw milk is placed in a wooden vat called a Tina. As no starter is added, lactic acid is produced by milk flora and flora released from the Tina biofilm. The aim of this work was to assess the safety and efficiency of this natural inoculation system. From 15 Tinas' biofilms, bacteria total

Sylvie Lortal; Annalisa Di Blasi; Marie-Noëlle Madec; Concetta Pediliggieri; Laura Tuminello; Gaëlle Tanguy; Jacques Fauquant; Yohan Lecuona; Patrizia Campo; Stefania Carpino; Giuseppe Licitra

2009-01-01

279

Studies on translocation, acute oral toxicity and intestinal colonization of potentially probiotic lactic acid bacteria administered during calf rearing  

Microsoft Academic Search

In order to test the harmlessness of potentially beneficial bacterial strains when raising young calves, their safety level should be verified before they are included into a probiotic formulation. In the present study, an inoculum composed of three lactic acid bacteria of bovine origin, Lactobacillus casei DSPV 318T, Lactobacillus salivarius DSPV 315T and Pediococcus acidilactici DSPV 006T, was evaluated to

L. S. Frizzo; E. Bertozzi; L. P. Soto; G. J. Sequeira; R. Rodriguez Armesto; M. R. Rosmini

2010-01-01

280

Selection criteria for lactic acid bacteria to be used as functional starter cultures in dry sausage production: An update  

Microsoft Academic Search

Lactic acid bacteria (LAB) have long been used as starter cultures in the production of fermented dry sausages and other meat-derived commodities. These cultures are generally designed to meet food safety, shelf-life, technological effectiveness and economic feasibility criteria. Besides all these traditional properties, novel starter cultures should take into account the risks posed by the formation of biogenic amines in

Mohammed Salim Ammor; Baltasar Mayo

2007-01-01

281

Role of lactic acid bacteria during meat conditioning and fermentation: Peptides generated as sensorial and hygienic biomarkers  

Microsoft Academic Search

The microbial ecology of meat fermentation is a complex process in which lactic acid bacteria (LAB) and coagulase-negative cocci play a major role. The present work reviews the most significant developments in which LAB are the main characters acting both as starter cultures improving the sensorial quality and as biopreservative agents. New findings about the identification of low molecular weight

Silvina Fadda; Constanza López; Graciela Vignolo

2010-01-01

282

Interaction between Lactic Acid Bacteria and Mycobacterium bovis in Ethiopian Fermented Milk: Insight into the Fate of M. bovis?  

PubMed Central

Mycobacterium bovis causes tuberculosis in animals and humans. Infected cows can transmit the bacillus to humans via milk. Milk also contains lactic acid bacteria (LAB). LAB isolated from milk were put in milk cultures together with spiked M. bovis. Different LAB had different abilities to reduce M. bovis counts, as M. bovis was undetectable in some while it persisted in two of the cultures.

Mariam, Solomon H.

2009-01-01

283

Enumeration of Lactobacillus casei in the presence of L. acidophilus, bifidobacteria and lactic starter bacteria in fermented dairy products  

Microsoft Academic Search

The aim of this work was to select a set of culture media to perform the enumeration of L. casei when it appears together with L. acidophilus, bifidobacteria and bacteria of lactic acid starters, in fermented dairy products. A number of L. acidophilus, Bifidobacterium and L. casei strains (8 of each) were tested for their ability to grow in two

C. G Vinderola; J. A Reinheimer

2000-01-01

284

Lactic acid bacteria and yeasts associated with spontaneous fermentations during the production of sour cassava starch in Brazil  

Microsoft Academic Search

Sour cassava starch is a traditional fermented food used in the preparation of fried foods and baked goods such as traditional cheese breads in Brazil. Thirty samples of sour cassava starch were collected from two factories in the state of Minas Gerais. The samples were examined for the presence of lactic acid bacteria, yeasts, mesophilic microorganisms, Bacillus cereus and faecal

Inayara C. A. Lacerda; Rose L. Miranda; Beatriz M. Borelli; Álvaro C. Nunes; Regina M. D. Nardi; Marc-André Lachance; Carlos A. Rosa

2005-01-01

285

Protein Pattern and Plasmid Profile of Lactic Acid Bacteria Isolated from Dahi, A Traditional Fermented Milk Product of Pakistan  

Microsoft Academic Search

Summary A total of 116 isolates were identified from randomly collected market dahi samples from Rawalpindi, Pakistan. Lactic acid bacteria dominated the microbial population of dahi and were identified according to their morphological and physiological characteristics. Among these lactobacilli were frequently occurring organisms. The phenotypic and bio- chemical analyses gave a diversity of species (8 presumptive species). The most abundant

Aijaz Hussain Soomro; Tariq Masud

2007-01-01

286

Effect of Temperature on Growth and Diacetyl Production by Aroma Bacteria in Single and Mixed-Strain Lactic Cultures1  

Microsoft Academic Search

By the use of a differential plating me- dium, the growth of aroma bacteria (Leu- conostoc citrovorum and Streptococcus di- acetilactis) in mixed-strain lactic starter cultures was followed. Populations were greater at 30 C than at the temperature (21 C) normally used in the dairy industry for incubation of cultures for manufacture of fermented dairy products. At 30 C, peak

M. Y. Pack; E. R. Vedamuthu; W. E. Sandine; P. R. Elliker; H. Leesment

1968-01-01

287

Effect of Quaternary Ammonium Compounds on Activity of Lactic Acid Starter Bacteria in Milk and Cheese1  

Microsoft Academic Search

The increased application of quaternary ammonium compounds (QAC) for dairy sanitation purposes has stimulated interest in the effect of various con- centrations of these compounds on the growth of lactic acid bacteria in milk. The problem is important from the standpoint of attempts to prevent souring of milk or to reduce bacterial counts prior to delivery to the dairy plant.

D. D. Miller; P. R. Elliker

1951-01-01

288

Production of four potentially probiotic lactic acid bacteria and their evaluation as feed additives for weaned piglets  

Microsoft Academic Search

The present study was conducted to study the production and evaluation of potentially probiotic additives containing both live lactic acid bacteria (Pediococcus acidilactici NRRL B-5627, Lactococcus lactis subsp. lactis CECT 539, Lactobacillus casei subsp. casei CECT 4043 and Enterococcus faecium CECT 410) and antimicrobial metabolites with could be used as a replacement for antibiotics in weanling pig diets. The gastrointestinal

Nelson Pérez Guerra; Paula Fajardo Bernárdez; Jesús Méndez; Pilar Cachaldora; Lorenzo Pastrana Castro

2007-01-01

289

Horizontal gene transfer amongst probiotic lactic acid bacteria and other intestinal microbiota: what are the possibilities? A review  

Microsoft Academic Search

Probiotics are live cultures, usually lactic acid bacteria, which are ingested to promote a healthy gastrointestinal tract.\\u000a These organisms require certain traits to survive and compete in this niche, but these traits may be transferred to other\\u000a microbiota in the gastrointestinal tract (GIT). Similarly, virulence factors from pathogens may be acquired by probiotic strains.\\u000a Bacteria have developed a plethora of

Carol A. van Reenen; Leon M. T. Dicks

2011-01-01

290

Fed-batch Fermentation of Lactic Acid Bacteria to Improve Biomass Production: A Theoretical Approach  

NASA Astrophysics Data System (ADS)

Recently, fed-batch fermentation has been introduced in an increasing number of fermentation processes. Previous researches showed that fed-batch fermentation can increase the biomass yield of many strains. Improvement of the biomass yield is interested because biomass from lactic acid bacteria (LAB) fermentation is widely used in food and pharmaceutical industry. The aim of this research is to study the ability and feasibility of fed-batch fermentation to improve biomass production of LAB. Appropriate model has been selected from literature. Monod equation described the substrate limitation of LAB and the product inhibition of LAB follows a non-competitive model. Furthermore, the lactic acid production follows Luedeking and Piret model. Then the models are applied to simulate the fermentation of batch and fed-batch cultures by using MATLAB. From the results of simulation, fed-batch fermentation showed that substrate limitation and substrate inhibition can be avoided. Besides that, the variable volume fed-batch fermentation also showed that product inhibition can be eliminated by diluting the product concentration with added fresh feed. However, it was found that fed-batch fermentation is not economically feasible because large amount of substrate is required to reduce the product inhibition effect. Therefore, fed-batch fermentation plays more importance role if the fermentation strain has high Ks value or low Kp value.

Beng Lee, Boon; Tham, Heng Jin; Chan, Eng Seng

291

Isolation and characteristics of lactic acid bacteria isolated from ripe mulberries in Taiwan  

PubMed Central

The objective of this study was to isolate, characterize, and identify lactic acid bacteria (LAB) from ripe mulberries collected in Taiwan. Ripe mulberry samples were collected at five mulberry farms, located in different counties of Taiwan. Eighty-eight acid-producing cultures were isolated from these samples, and isolates were divided into classes first by phenotype, then into groups by restriction fragment length polymorphism (RFLP) analysis and sequencing of 16S ribosomal DNA (rDNA). Phenotypic and biochemical characteristics led to identification of four bacterial groups (A to D). Weissella cibaria was the most abundant type of LAB distributed in four mulberry farms, and Lactobacillus plantarum was the most abundant LAB found in the remaining farm. Ten W. cibaria and one Lactococcus lactis subsp. lactis isolate produced bacteriocins against the indicator strain Lactobacillus sakei JCM 1157T. These results suggest that various LAB are distributed in ripe mulberries and W. cibaria was the most abundant LAB found in this study.

Chen, Yi-sheng; Wu, Hui-chung; Yanagida, Fujitoshi

2010-01-01

292

Mucosal targeting of therapeutic molecules using genetically modified lactic acid bacteria: an update.  

PubMed

Lactic acid bacteria (LAB) represent a heterogeneous group of microorganisms naturally present in many foods and those have proved to be effective mucosal delivery vectors. Moreover, some specific strains of LAB exert beneficial properties (known as probiotic effect) on both human and animal health. Although probiotic effects are strain-specific traits, it is theoretically possible, using genetic engineering techniques, to design strains that can exert a variety of beneficial properties. During the two past decades, a large variety of therapeutic molecules has been successfully expressed in LAB, and although this field has been largely reviewed in recent years, approximately 20 new publications appear each year. Thus, the aim of this minireview is not to extensively assess the entire literature but to update progress made within the last 2 years regarding the use of the model LAB Lactococcus lactis and certain species of lactobacilli as live recombinant vectors for the development of new safe mucosal vaccines. PMID:23600579

LeBlanc, Jean Guy; Aubry, Camille; Cortes-Perez, Naima G; de Moreno de LeBlanc, Alejandra; Vergnolle, Nathalie; Langella, Philippe; Azevedo, Vasco; Chatel, Jean-Marc; Miyoshi, Anderson; Bermúdez-Humarán, Luis G

2013-05-16

293

Inhibition of mycotoxin-producing Aspergillus nomius vsc 23 by lactic acid bacteria and Saccharomyces cerevisiae  

PubMed Central

The effect of different fermenting microorganisms on growth of a mycotoxin- producing Aspergillus nomius was assayed. Two lactic acid bacteria, Lactobacillus fermentum and Lactobacillus rhamnosus, and Saccharomyces cerevisiae, all of which are widely used in fermentation and preservation of food, were assayed on their fungus inhibitory properties. Assays were carried out by simultaneous inoculation of one of the possible inhibiting microorganisms and the fungus or subsequent inoculation of one of the microorganisms followed by the fungus. All three microorganisms assayed showed growth inhibition of the mycotoxin-producing Aspergillus strain. L. rhamnosus O236, isolated from sheep milk and selected for its technological properties, showed highest fungal inhibition of the microorganisms assayed. The use of antifungal LAB with excellent technological properties rather than chemical preservatives would enable the food industry to produce organic food without addition of chemical substances.

Munoz, R; Arena, M.E.; Silva, J.; Gonzalez, S.N.

2010-01-01

294

Traditional Indian fermented foods: a rich source of lactic acid bacteria.  

PubMed

This review describes the diversity of Indian fermented food and its significance as a potential source of lactic acid bacteria (LAB). Fermented foods consumed in India are categorized based upon their base material. Fermented foods such as dahi, gundruk, sinki, iniziangsang, iromba, fermented rai, kanjika and handua were reported to have significant medicinal properties. Some fermented products such as koozh, dahi and kanjika are consumed unknowingly as, probiotic drinks, by local people. There are very few reports regarding isolation of LAB from Indian fermented foods available in the past; however, due to growing consciousness about potential health benefits of LAB, we now have scores of reports in this field. There is an abundant opportunity available for food microbiologists to explore the Indian fermented foods for the isolation of new LAB strains for their potential role in probiotic research. PMID:23181843

Satish Kumar, R; Kanmani, P; Yuvaraj, N; Paari, K A; Pattukumar, V; Arul, V

2012-11-27

295

Characterization of enterocin- and salivaricin-producing lactic acid bacteria from the mammalian gastrointestinal tract.  

PubMed

Bacteriocin production may be a factor contributing to bacterial dominance within complex microbial populations and may therefore be a common trait within the gut microbiota. However, of 278 antimicrobial-producing culturable lactic acid bacteria (LAB) isolated from a range of mammalian intestinal sources in this study, characterization revealed just 23 distinct strains producing bacteriocin-like inhibitory substances and one Streptococcus hyointestinalis strain producing a potentially novel protease-insensitive antimicrobial. Three class II bacteriocins previously isolated from intestinal-derived LAB were identified as enterocin A and two salivaricin P-like bacteriocins. Moreover, this is the first report of intestinal-derived Streptococcus salivarius producing variants of the lantibiotic salivaricin A. PMID:19076236

O'Shea, Eileen F; Gardiner, Gillian E; O'Connor, Paula M; Mills, Susan; Ross, R Paul; Hill, Colin

2008-12-03

296

Lactic acid bacteria from chicken carcasses with inhibitory activity against Salmonella spp. and Listeria monocytogenes.  

PubMed

This study was conducted to isolate psychrotrophic lactic acid bacteria (LAB) from chicken carcasses with inhibitory activity against strains of Salmonella spp. and Listeria monocytogenes. A total of 100 broiler samples were examined for the presence of LAB. Ninety-two LAB isolates that showed antimicrobial effects against Salmonella spp. and L. monocytogenes were further analysed to examine their LAB (Gram-positive, catalase negative, oxidase negative) and psychrotrophic characteristics (ability to grow at 7 °C). Fifty isolates were further selected and identified initially using standard biochemical tests in miniature (Micro-kits API CH 50) and then by sequencing of the 16s-23s rRNA gene boundary region (Intergenic Spacer Region). By molecular identification, these isolates were classified into 5 different LAB species: Lactobacillus salivarius, Lactobacillus reuteri, Lactobacillus johnsonii, Pediococcus acidilactici, and Lactobacillus paralimentarius. None of the isolates produced tyramine or histamine. PMID:21983108

Sakaridis, I; Soultos, N; Dovas, C I; Papavergou, E; Ambrosiadis, I; Koidis, P

2011-10-01

297

In vitro testing of commercial and potential probiotic lactic acid bacteria.  

PubMed

Probiotics are defined as live microorganisms which when administered in adequate amounts confer a health benefit on the host. The objective of this study was to investigate the diversity of selected commercial and potential probiotic lactic acid bacteria using common in vitro screening assays such as transit tolerance in the upper human gastrointestinal tract, adhesion capacity to human intestinal cell lines and effect on epithelial barrier function. The selected bacteria include strains of Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus farciminis, Lactobacillus sakei, Lactobacillus gasseri, Lactobacillus rhamnosus, Lactobacillus reuteri and Pediococcus pentosaceus. Viable counts after simulated gastric transit tolerance showed that L. reuteri strains and P. pentosaceus tolerate gastric juice well, with no reduction of viability, whereas L. pentosus, L. farciminis and L. sakei strains lost viability over 180min. All strains tested tolerate the simulated small intestinal juice well. The bacterial adhesion capacity to human intestinal cells revealed major species and strain differences. Overall, L. plantarum MF1298 and three L. reuteri strains had a significant higher adhesion capacity compared to the other strains tested. All strains, both living and UV-inactivated, had little effect on the epithelial barrier function. However, living L. reuteri strains revealed a tendency to increase the transepithelial electrical resistance (TER) from 6 to 24h. This work demonstrates the diversity of 18 potential probiotic bacteria, with major species and strain specific effects in the in vitro screening assays applied. Overall, L. reuteri strains reveal some interesting characteristics compared to the other strains investigated. PMID:22177712

Jensen, Hanne; Grimmer, Stine; Naterstad, Kristine; Axelsson, Lars

2011-12-01

298

Lactic acid bacteria associated with the digestive tract of Atlantic salmon (Salmo salar L.).  

PubMed

The present study reports the effect of excessive handling stress and starvation on the lactic acid bacteria associated with the digestive tract of Atlantic salmon (Salmo salar L.). A relatively low population level (approximately 2 x 103 bacteria per gram wet tissue) of viable adherent heterotrophic bacteria was associated with the digestive tract (foregut, midgut and hindgut). Of the 752 bacterial isolates isolated from diet, water and the digestive tract, 201 isolates belonged to the carnobacteria. Of these isolates, one from the diet, one from the rearing water and 80 from the gastrointestinal tract, were further identified on the basis of 16S rDNA sequence analysis. All these isolates were identified as being Carnobacterium piscicola-like. Daily repeated stress and starvation of the fish over 11 d had no influence on the total culturable bacterial numbers or population level of C. piscicola associated with the digestive tract. C. piscicola-like isolates colonizing the various intestinal regions (foregut, midgut and hindgut) were also screened for their ability to produce growth inhibitory compounds active against the fish pathogen Aeromonas salmonicida. Of the 199 C. piscicola isolates tested, 139 inhibited growth of the pathogen. PMID:10971765

Ringø, E; Bendiksen, H R; Wesmajervi, M S; Olsen, R E; Jansen, P A; Mikkelsen, H

2000-08-01

299

Psychrotrophic, lactic acid-producing bacteria from anoxic waters in Ace Lake, Antarctica; Carnobacterium funditum sp. nov. and Carnobacterium alterfunditum sp. nov  

Microsoft Academic Search

Heterofermentative, lactic acid-producing, gram-positive, motile bacteria were isolated from the waters of Ace Lake, Antarctica. All strains produced virtually only l(+)lactic acid from d(+)glucose. d(-)ribose was fermented to lactic, acetic, and formic acids, and ethanol. Cell walls contained meso-diaminopimaleic acid. The strains did not grow at 30°C and were psychrotrophic. Whole cells contained 18:1cis 9 as a major component of

P. D. Franzmann; P. Höpfl; N. Weiss; B. J. Tindall

1991-01-01

300

Numbers, diversity, and morphological characteristics of aerobic, chemoheterotrophic bacteria in deep subsurface sediments from a site in South Carolina  

Microsoft Academic Search

The aerobic, chemoheterotrophic bacteria indigenous to deep aquifers and other subsurface sediments (depths to 265 m) at a site in South Carolina were characterized by direct microscopy, enumeration of viable cells, analysis of colony morphologies on plates, and analysis of cell morphologies of isolated strains. Substantial numbers of viable bacteria (1010\\/g) were present in all transmissive, aquifer sediments, and their

David L. Balkwill

1989-01-01

301

Effect of radiation dose on the recovery of aerobic and anaerobic bacteria from mice  

SciTech Connect

The presence of aerobic and anaerobic bacteria in the blood, spleen, and liver was investigated in mice that were exposed to 7, 8, 9, or 10 Gy /sup 60/Co radiation. Microorganisms were detected more often in animals exposed to higher doses of radiation. The number of mice that were culture positive and the number of isolates in one site increased with increasing dose. Bacteria were recovered in mice killed at various times after radiation, in 3 of 100 mice exposed to 7 Gy, in 13 of 100 irradiated with 8 Gy, in 23 of 90 exposed to 9 Gy, and in 34 of 87 irradiated with 10 Gy. The predominant organisms recovered were Escherichia coli, anerobic Gram-positive cocci, Proteus mirabilis, Staphylococcus aureus, and Bacteroides spp. Escherichia coli and anaerobes were more often isolated in animals exposed to 10 Gy, while S. aureus was more often recovered in those irradiated with 9 Gy. These data demonstrate a relationship between the dose of radiation and the rate of infection due to entire aerobic and anaerobic bacteria. Reprints.

Brook, I.; Walker, R.I.; MacVittie, T.J.

1986-01-01

302

Development and validation of a species-independent functional gene microarray that targets lactic acid bacteria.  

PubMed

During the last few years, genome-related information has become available for many microorganisms, including important food-related bacteria. Lactic acid bacteria (LAB) are important industrially in the production of fermented foods such as dairy products, sausages, sourdoughs, and vegetables. Despite their limited metabolic capacity, LAB contribute considerably to important characteristics of fermented foods, such as flavor and texture. In the present study, a species-independent functional gene microarray was developed that targets 406 genes that play key roles in the production of sugar catabolites, bacteriocins, exopolysaccharides, and aromas, in probiotic and biosafety characteristics, and in the stress response. Also, genes linked to negative traits, such as antibiotic resistance and virulence, are represented. As LAB ecosystems contain a variety of species, there was a more global focus on these specific functional properties. Thus, an algorithm was used to design gene-specific oligonucleotides that preferably hybridize with multiple LAB species, thereby allowing controlled cross-hybridization. For proof of concept, the microarray composed of 2,269 30-mer oligonucleotides focused on LAB species that are prevalent in sourdough ecosystems. Validation hybridizations using DNA and RNA from 18 LAB strains, covering 86% of all the oligonucleotides, showed that there were wide ranges in intensity and high reproducibility between microarrays. PMID:19684161

Weckx, Stefan; Allemeersch, Joke; Van der Meulen, Roel; Vrancken, Gino; Huys, Geert; Vandamme, Peter; Van Hummelen, Paul; De Vuyst, Luc

2009-08-14

303

Relevance and application of sortase and sortase-dependent proteins in lactic acid bacteria  

PubMed Central

Lactic acid bacteria (LAB) are a diverse group of Gram-positive bacteria found in a vast array of environments including dairy products and the human gastrointestinal tract (GIT). In both niches, surface proteins play a crucial role in mediating interactions with the surrounding environment. The sortase enzyme is responsible for covalently coupling a subset of sortase-dependent proteins (SDPs) to the cell wall of Gram-positive organisms through recognition of a conserved C-terminal LPXTG motif. Genomic sequencing of LAB and annotation has allowed for the identification of sortase and SDPs. Historically, sortase and SDPs were predominately investigated for their role in mediating pathogenesis. Identification of these proteins in LAB has shed light on their important roles in mediating nutrient acquisition through proteinase P as well as positive probiotic attributes including adhesion, mucus barrier function, and immune signaling. Furthermore, sortase expression signals in LAB have been exploited as a means to develop oral vaccines targeted to the GIT. In this review, we examine the collection of studies which evaluate sortase and SDPs in select species of dairy-associated and health promoting LAB.

Call, Emma K.; Klaenhammer, Todd R.

2013-01-01

304

Growth of Lactic Acid Bacteria in Waste Waters of Vegetable-Processing Plants  

PubMed Central

Waters used in washing, blanching, cooling, and conveying vegetables during processing for freezing were filtered, sterilized, and inoculated with Streptococcus faecalis, S. lactis, or Lactobacillus plantarum. The contents of total nitrogen and total solids were determined, and ninhydrin tests and Benedict's tests for reducing sugars were performed. Substances positive to the ninyhydrin tests and also capable of supporting the growth of the bacteria to high levels of population were found in waters used to blanch cut green beans, but not in the cooling or conveying waters. They were found only in waters following slicing of blanched whole beans. They were also present in waters used in processing purple hull peas at all stages, but only in the waters used to blanch and cool lima beans. The substances were present in waters used to wash and blanch squash, but only in the waters used to blanch greens; they were not found in the cooling waters during the handling of either vegetable. No waters used in the processing of okra yielded a positive ninhydrin test, nor did they support the growth of the lactic acid bacteria.

Mundt, J. Orvin; Larsen, Sandra A.; McCarty, I. E.

1966-01-01

305

Biofilm formation by lactic acid bacteria and resistance to environmental stress.  

PubMed

We investigated the formation of biofilms by 3 type strains of lactic acid bacteria (LAB), Lactobacillus plantarum, Lactobacillus brevis and Lactobacillus fructivorans, as representatives of LAB that cause food deterioration or contamination. Lactobacillus plantarum subsp. plantarum JCM1149 and Lactobacillus brevis JCM1059 appeared to adhere and accumulate on glass cover slips. Lactobacillus fructivorans JCM1117 cells made thin cellophane-like biofilms, and most of the biofilm cells became longer than the planktonic cells. We tested the resistance of biofilm and planktonic L. plantarum subsp. plantarum JCM1149 cells to acetic acid and ethanol, which strongly inhibit the growth of bacteria and are important in food preservation. The biofilm cells were more resistant than the planktonic cells and the surfaces of the treated planktonic cells were badly damaged, whereas those of the biofilm cells were only slightly damaged. We isolated 43 LAB from onions and the biofolm cells of an isolate, L. plantarum M606 also had high resistance. These results demonstrate the significance of studying biofilms of LAB in the food industry. PMID:19000615

Kubota, Hiromi; Senda, Shouko; Nomura, Nobuhiko; Tokuda, Hajime; Uchiyama, Hiroo

2008-10-01

306

Comparative genomics of lactic acid bacteria reveals a niche-specific gene set  

PubMed Central

Background The recently sequenced genome of Lactobacillus helveticus DPC4571 [1] revealed a dairy organism with significant homology (75% of genes are homologous) to a probiotic bacteria Lb. acidophilus NCFM [2]. This led us to hypothesise that a group of genes could be determined which could define an organism's niche. Results Taking 11 fully sequenced lactic acid bacteria (LAB) as our target, (3 dairy LAB, 5 gut LAB and 3 multi-niche LAB), we demonstrated that the presence or absence of certain genes involved in sugar metabolism, the proteolytic system, and restriction modification enzymes were pivotal in suggesting the niche of a strain. We identified 9 niche specific genes, of which 6 are dairy specific and 3 are gut specific. The dairy specific genes identified in Lactobacillus helveticus DPC4571 were lhv_1161 and lhv_1171, encoding components of the proteolytic system, lhv_1031 lhv_1152, lhv_1978 and lhv_0028 encoding restriction endonuclease genes, while bile salt hydrolase genes lba_0892 and lba_1078, and the sugar metabolism gene lba_1689 from Lb. acidophilus NCFM were identified as gut specific genes. Conclusion Comparative analysis revealed that if an organism had homologs to the dairy specific geneset, it probably came from a dairy environment, whilst if it had homologs to gut specific genes, it was highly likely to be of intestinal origin. We propose that this "barcode" of 9 genes will be a useful initial guide to researchers in the LAB field to indicate an organism's ability to occupy a specific niche.

2009-01-01

307

Phylogenetic and Kinetic Diversity of Aerobic Vinyl Chloride-Assimilating Bacteria from Contaminated Sites  

PubMed Central

Aerobic bacteria that grow on vinyl chloride (VC) have been isolated previously, but their diversity and distribution are largely unknown. It is also unclear whether such bacteria contribute to the natural attenuation of VC at chlorinated-ethene-contaminated sites. We detected aerobic VC biodegradation in 23 of 37 microcosms and enrichments inoculated with samples from various sites. Twelve different bacteria (11 Mycobacterium strains and 1 Nocardioides strain) capable of growth on VC as the sole carbon source were isolated, and 5 representative strains were examined further. All the isolates grew on ethene in addition to VC and contained VC-inducible ethene monooxygenase activity. The Mycobacterium strains (JS60, JS61, JS616, and JS617) all had similar growth yields (5.4 to 6.6 g of protein/mol), maximum specific growth rates (0.17 to 0.23 day?1), and maximum specific substrate utilization rates (9 to 16 nmol/min/mg of protein) with VC. The Nocardioides strain (JS614) had a higher growth yield (10.3 g of protein/mol), growth rate (0.71 day?1), and substrate utilization rate (43 nmol/min/mg of protein) with VC but was much more sensitive to VC starvation. Half-velocity constant (Ks) values for VC were between 0.5 and 3.2 ?M, while Ks values for oxygen ranged from 0.03 to 0.3 mg/liter. Our results indicate that aerobic VC-degrading microorganisms (predominantly Mycobacterium strains) are widely distributed at sites contaminated with chlorinated solvents and are likely to be responsible for the natural attenuation of VC.

Coleman, Nicholas V.; Mattes, Timothy E.; Gossett, James M.; Spain, Jim C.

2002-01-01

308

Mannitol production by lactic acid bacteria grown in supplemented carob syrup.  

PubMed

Detailed kinetic and physiological characterisation of eight mannitol-producing lactic acid bacteria, Leuconostoc citreum ATCC 49370, L. mesenteroides subsp. cremoris ATCC19254, L. mesenteroides subsp. dextranicum ATCC 19255, L. ficulneum NRRL B-23447, L. fructosum NRRL B-2041, L. lactis ATCC 19256, Lactobacillus intermedius NRRL 3692 and Lb. reuteri DSM 20016, was performed using a carob-based culture medium, to evaluate their different metabolic capabilities. Cultures were thoroughly followed for 30 h to evaluate consumption of sugars, as well as production of biomass and metabolites. All strains produced mannitol at high yields (>0.70 g mannitol/g fructose) and volumetric productivities (>1.31 g/l h), and consumed fructose and glucose simultaneously, but fructose assimilation rate was always higher. The results obtained enable the studied strains to be divided mainly into two groups: one for which glucose assimilation rates were below 0.78 g/l h (strains ATCC 49370, ATCC 19256 and ATCC 19254) and the other for which they ranged between 1.41 and 1.89 g/l h (strains NRRL B-3692, NRRL B-2041, NRRL B-23447 and DSM 20016). These groups also exhibited different mannitol production rates and yields, being higher for the strains with faster glucose assimilation. Besides mannitol, all strains also produced lactic acid and acetic acid. The best performance was obtained for L. fructosum NRRL B-2041, with maximum volumetric productivity of 2.36 g/l h and the highest yield, stoichiometric conversion of fructose to mannitol. PMID:20820868

Carvalheiro, Florbela; Moniz, Patrícia; Duarte, Luís C; Esteves, M Paula; Gírio, Francisco M

2010-09-05

309

Selection of potential probiotic lactic acid bacteria from fermented olives by in vitro tests.  

PubMed

The present study aims to evaluate the probiotic potential of lactic acid bacteria (LAB) isolated from naturally fermented olives and select candidates to be used as probiotic starters for the improvement of the traditional fermentation process and the production of newly added value functional foods. Seventy one (71) lactic acid bacterial strains (17 Leuconostoc mesenteroides, 1 Ln. pseudomesenteroides, 13 Lactobacillus plantarum, 37 Lb. pentosus, 1 Lb. paraplantarum, and 2 Lb. paracasei subsp. paracasei) isolated from table olives were screened for their probiotic potential. Lb. rhamnosus GG and Lb. casei Shirota were used as reference strains. The in vitro tests included survival in simulated gastrointestinal tract conditions, antimicrobial activity (against Listeria monocytogenes, Salmonella Enteritidis, Escherichia coli O157:H7), Caco-2 surface adhesion, resistance to 9 antibiotics and haemolytic activity. Three (3) Lb. pentosus, 4 Lb. plantarum and 2 Lb. paracasei subsp. paracasei strains demonstrated the highest final population (>8 log cfu/ml) after 3 h of exposure at low pH. The majority of the tested strains were resistant to bile salts even after 4 h of exposure, while 5 Lb. plantarum and 7 Lb. pentosus strains exhibited partial bile salt hydrolase activity. None of the strains inhibited the growth of the pathogens tested. Variable efficiency to adhere to Caco-2 cells was observed. This was the same regarding strains' susceptibility towards different antibiotics. None of the strains exhibited ?-haemolytic activity. As a whole, 4 strains of Lb. pentosus, 3 strains of Lb. plantarum and 2 strains of Lb. paracasei subsp. paracasei were found to possess desirable in vitro probiotic properties similar to or even better than the reference probiotic strains Lb. casei Shirota and Lb. rhamnosus GG. These strains are good candidates for further investigation both with in vivo studies to elucidate their potential health benefits and in olive fermentation processes to assess their technological performance as novel probiotic starters. PMID:23200662

Argyri, Anthoula A; Zoumpopoulou, Georgia; Karatzas, Kimon-Andreas G; Tsakalidou, Effie; Nychas, George-John E; Panagou, Efstathios Z; Tassou, Chrysoula C

2012-10-31

310

Phenotypic and genotypic analyses of lactic acid bacteria in local fermented food, breast milk and faeces of mothers and their babies  

Microsoft Academic Search

Lactic acid bacteria (LAB) are generally accepted as beneficial to the host and their presence is directly influenced by ingestion of fermented food or probiotics. While the intestinal lactic microbiota is well-described knowledge on its routes of inoculation and competitiveness towards selective pressure shaping the intestinal microbiota is limited. In this study, LAB were isolated from faecal samples of breast

Rima Albesharat; Matthias A. Ehrmann; Maher Korakli; Sabah Yazaji; Rudi F. Vogel

2011-01-01

311

Microbial and Physiological Characterization of Weakly Amylolytic but Fast-Growing Lactic Acid Bacteria: a Functional Role in Supporting Microbial Diversity in Pozol, a Mexican Fermented Maize Beverage  

Microsoft Academic Search

Pozol is an acid beverage obtained from the natural fermentation of nixtamal (heat- and alkali-treated maize) dough. The concentration of mono- and disaccharides from maize is reduced during nixtamalization, so that starch is the main carbohydrate available for lactic acid fermentation. In order to provide some basis to understand the role of amylolytic lactic acid bacteria (ALAB) in this fermented

G. Diaz-Ruiz; J. P. Guyot; F. Ruiz-Teran; J. Morlon-Guyot; C. Wacher

2003-01-01

312

Molecular characterization of lactic acid bacteria and in situ amylase expression during traditional fermentation of cereal foods.  

PubMed

Lactic acid bacteria play an important role in traditional fermented foods consumed in different countries. Study of their taxonomic structure and diversity is necessary for starter culture selection, improved safety and nutritional enhancement. To achieve these objectives, microbial genomic typing methods were used to study genetic differences of autochthonous bacteria and their distribution in two traditional African fermented cereal foods. A total of 85 predominant bacterial species were isolated from ogi and kunu-zaki obtained from Northern and Southern geographical region of Nigeria. They were identified using combination of 16S rRNA gene sequencing, multilocus sequence analysis (MLSA) based on rpoA, pheS and atpA genes as well as M13-PCR gel fingerprints. The results showed that Lactobacillus fermentum was the most frequently isolated species in ogi (71.4%) and kunu-zaki (84.5%). Other species of lactic acid bacteria (LAB) identified were Lactobacillus plantarum, Streptococcus gallolyticus subsp. macedonicus and Pediococcus pentosaceus. Non lactic acid bacteria isolated from these foods were species belonging to the Bacillus and Staphylococcus. Non-metric multidimensional scaling (nMDS) analysis of the M13-PCR fingerprints for LAB strains showed clonal diversity among strains of the same species. In vitro and in situ expression of amylase gene during fermentation by amylolytic L. plantarum ULAG11 was detected, indicating the potential usefulness of such species for development of starter cultures and for controlled fermentation processes. PMID:22608231

Oguntoyinbo, Folarin Anthony; Narbad, Arjan

2012-03-21

313

Population of aerobic heterotrophic nitrogen-fixing bacteria associated with wetland and dryland rice  

SciTech Connect

Nitrogen-fixing activity and populations of nitrogen-fixing bacteria associated with two varieties of rice grown in dryland and wetland conditions were measured at various growth stages during the dry season. Acetylene reduction activities were measured both in the field and for the hydroponically grown rice, which was transferred from the field to water culture 1 day before assay. The activities measured by both methods were higher in wetland than in dryland rice. The population of nitrogen-fixing heterotrophic bacteria associated with rhizosphere soil, root, and basal shoots was determined by the most probable number method with semisolid glucose-yeast extract and semisolid malate-yeast extract media. The number of nitrogen-fixing bacteria was higher in wetland conditions than in dryland conditions. The difference between two conditions was most pronounced in the population associated with the basal shoot. The glucose medium gave higher counts than did the malate medium. Colonies were picked from tryptic soy agar plates, and their nitrogen-fixing activity was tested on a semisolid glucose-yeast extract medium. The incidence of nitrogen-fixing bacteria among aerobic heterotrophic bacteria in association with rhizosphere soil, root, and basal shoots was much lower in dryland rice than in wetland rice. (Refs. 11).

Barraquio, W.L.; De Guzman, M.R.; Barrion, M.; Watanahe, I.

1982-01-01

314

Diversity of aerobic and anaerobic ammonia-oxidizing bacteria in marine sponges.  

PubMed

Aerobic ammonia-oxidizing bacteria (AAOB) are known to have an important function in the marine nitrogen cycle. Anaerobic ammonium oxidation (anammox) carried out by some members of Planctomycetales is also an important process in marine ecosystems. Ammonia-monooxygenase gene (amoA) fragments were amplified to investigate the potential for nitrification and the diversity of the AAOB in two marine sponges Ircinia strobilina and Mycale laxissima. All of the AmoA sequences obtained from the two sponges clustered with the AmoA sequences of the Betaproteobacteria Nitrosospira spp. To investigate the anaerobic ammonia-oxidizing bacteria (AnAOB) in sponges, 16S rRNA gene fragments of Planctomycetales and anammox bacteria were also amplified with specific primers, and clone libraries were constructed. The Planctomycetales diversity detected in the two sponges was different. The Planctomycetales community in M. laxissima was affiliated with Pirellula, Planctomyces and anammox bacteria, while all of the I. strobilina Planctomycetales clones were solely affiliated with the candidate phylum 'Poribacteria'. Interestingly, sequences related to anammox genera were recovered only from M. laxissima. This is the first report of anammox bacteria in marine sponges. It is intriguing to find AAOB and AnAOB in M. laxissima, but the nature of their interaction with the sponge host and with each other remains unclear. This work further supports the potential of sponge-associated microorganisms for nitrification and sheds light on anammox as a new aspect of the nitrogen cycle in marine sponges. PMID:19617876

Mohamed, Naglaa M; Saito, Keiko; Tal, Yossi; Hill, Russell T

2009-07-16

315

Production of potentially probiotic beverages using single and mixed cereal substrates fermented with lactic acid bacteria cultures.  

PubMed

In the present work, single and mixed cereal substrates were fermented with lactic acid bacteria to study and compare the effect of the media formulation on fermentation parameters. Three cereal flours namely malt, barley and barley mixed with malt (barley-malt) were selected and fermented with two probiotic strains: Lactobacillus plantarum (NCIMB 8826) and Lactobacillus acidophilus (NCIMB 8821). The effect of the single and mixed cereal flour suspensions on the fermentation of these two strains of lactic acid bacteria (LAB) was studied at an incubation temperature of 30 °C for 28 h. It was found that the LAB growth was enhanced in media containing malt and significant amounts of lactic acid were produced (0.5-3.5 g/L). A cell concentration between 7.9 and 8.5 Log?? CFU/mL and a pH below 4.0 was achieved within 6 h of fermentation. Though the cell populations in the mixed culture fermentations of mixed substrates were similar to the ones obtained with single cereal flours, significant differences in the production of lactic acid were observed. These results suggest that the functional and organoleptic properties of these cereal-based probiotic drinks could be considerably modified through changes in the substrate or inocula composition. PMID:22265307

Rathore, Sorbhi; Salmerón, Ivan; Pandiella, Severino S

2011-09-24

316

Viability of lactic acid bacteria and bifidobacteria in fermented soymilk after drying, subsequent rehydration and storage.  

PubMed

To develop a probiotic dietary adjunct, soymilk fermented with various combinations of lactic acid bacteria (Streptococcus thermophilus and Lactobacillus acidophilus) and bifidobacteria (Bifidobacterium longum and Bifidobacterium infantis) was subjected to freeze-drying and spray-drying. Survival of the starter organisms during the drying process, subsequent rehydration at different temperatures and during a 4-month period of storage under different storage conditions was examined. After freeze-drying, lactic acid bacteria and bifidobacteria exhibited a survival percent of 46.2-75.1% and 43.2-51.9%, respectively, higher than that noted after spray-drying. Regardless of the drying condition, S. thermophilus showed a higher percentage of survival than L. acidophilus, while B. longum survived better than B. infantis. Further study with soymilk fermented with S. thermophilus and B. longum revealed that the freeze-dried and spray-dried fermented soymilk rehydrated at 35-50 degrees C and 20 degrees C, respectively, was optimum for the recovery of the starter organisms. Both S. thermophilus and B. longum survived better in the freeze-dried than the spray-dried fermented soymilk during storage. A higher percent of survival was also noted for both the starter organisms when the dried fermented soymilk was stored at 4 degrees C than 25 degrees C. Holding the dried fermented soymilk in the laminated pouch enabled S. thermophilus and B. longum to exhibit a higher percentage of survival than in the deoxidant- and desiccant-containing glass or polyester (PET) bottle. Among all the packaging materials and storage temperatures tested, starter organisms were most stable in the dried fermented soymilk held in laminated pouch and stored at 4 degrees C. Under this storage condition, S. thermophilus and B. longum showed a survival percentage of 51.1% and 68.8%, respectively, in the freeze-dried fermented soymilk after 4 months of storage. Meanwhile, S. thermophilus and B. infantis in the spray-dried fermented soymilk showed a survival percent of 29.5% and 57.7%, respectively. PMID:15135959

Wang, Yi-Chieh; Yu, Roch-Chui; Chou, Cheng-Chun

2004-06-01

317

Ability of dairy strains of lactic acid bacteria to bind aflatoxin M1 in a food model.  

PubMed

Aflatoxin M1 (AFM1) is a highly toxic compound found in milk. Its occurrence poses a threat to the health of consumers, especially young children, and leads to economic losses due to contaminated milk. The problem is global but more severe in developing countries. Consequently, there is a great demand for novel strategies to prevent the contamination and adverse effects of AFM1. To develop a safe and practical decontamination method, a preliminary study was carried out with specific lactic acid bacteria strains that were tested for their ability to remove AFM1 from liquid media. All strains, whether viable or heat-killed, could reduce the AFM1 content of a liquid medium. Two most effective strains were also tested using contaminated skim and full cream milk. The results indicate that specific lactic acid bacteria used in dairy products can offer novel means of decontaminating aflatoxin M1 from milk. PMID:10826723

Pierides, M; El-Nezami, H; Peltonen, K; Salminen, S; Ahokas, J

2000-05-01

318

Elucidation of the Taxonomic Status of Industrial Strains of Thermophilic Lactic Acid Bacteria by Sequencing of 16S rRNA Genes  

Microsoft Academic Search

Both phenotypic characteristics and results of PCR tests for the presence of species-specific genes indicate that a number of strains of thermophilic lactic acid bacteria previously considered as belonging to Streptococcus thermophilus are actually closely related to enterococci. In the present study, partial (over 500 nucleotides) sequencing of 16S rRNA genes from 12 strains of thermophilic lactic acid bacteria used

S. G. Botina; A. M. Lysenko; V. V. Sukhodolets

2005-01-01

319

Proteolysis by Sourdough Lactic Acid Bacteria: Effects on Wheat Flour Protein Fractions and Gliadin Peptides Involved in Human Cereal Intolerance  

Microsoft Academic Search

Sourdough lactic acid bacteria were preliminarily screened for proteolytic activity by using a digest of albumin and globulin polypeptides as a substrate. Based on their hydrolysis profile patterns, Lactobacillus alimentarius 15M, Lactobacillus brevis 14G, Lactobacillus sanfranciscensis 7A, and Lactobacillus hilgardii 51B were selected and used in sourdough fermentation. A fractionated method of protein extraction and subsequent two-dimensional electrophoresis were used

Raffaella Di Cagno; Maria De Angelis; Paola Lavermicocca; Massimo De Vincenzi; Claudio Giovannini; Michele Faccia; Marco Gobbetti

2002-01-01

320

Atherosclerosis-Preventing Activity of Lactic Acid Bacteria-Fermented Milk?Soymilk Supplemented with Momordica charantia  

Microsoft Academic Search

In this study, the milk-soymilk and milk-soymilk supplemented with Momordica charantia, a common oriental vegetable possessing medicinal activities, were fermented by lactic bacteria. The objective of this study was to investigate the effects of milk-soymilk and fermented milk-soymilk with or without M. charantia on atherosclerosis in hyperlipidemic hamsters. Fermented 25% milk and 75% soymilk combinations, supplemented with 1% M. charantia

Tsung-Yu Tsai; Li-Han Chu; Chun-Lin Lee; Tzu-Ming Pan

2009-01-01

321

The potential of dairy lactic acid bacteria to metabolise amino acids via non-transaminating reactions and endogenous transamination  

Microsoft Academic Search

The metabolism of amino acids by 22 starter and 49 non-starter lactic acid bacteria (LAB) was studied in a system consisting of amino acids and non-growing cells without added amino acceptors such as ?-ketoglutarate. There were significant inter- and intra-species differences in the metabolism of amino acids. Some amino acids such as alanine, arginine, aspartate, serine and branched-chain amino acids

S.-Q. Liu; R. Holland; V. L. Crow

2003-01-01

322

Screening for anti-listerial bacteriocin-producing lactic acid bacteria from “Gueddid” a traditionally Tunisian fermented meat  

Microsoft Academic Search

Forty eight lactic acid bacteria strains isolated from “Gueddid”, a traditionally Tunisian fermented meat, were screened for bacteriocin production. Four strains named MMZ 04, 09, 13, and 17 showed antimicrobial activity and were identified as Enterococcus faecium by molecular methods based on the 16S-23S rDNA ISR, PCR-RFLP analysis of the 16S-23S rDNA ISR and species-specific primers. The four antimicrobial compounds

Zouhaier Ben Belgacem; Mounir Ferchichi; Hervé Prévost; Xavier Dousset; Mohamed Manai

2008-01-01

323

Antimould activity of sourdough lactic acid bacteria: identification of a mixture of organic acids produced by Lactobacillus sanfrancisco CB1  

Microsoft Academic Search

Sourdough lactic acid bacteria, cultivated in wheat flour hydrolysate, produced antimould compounds. The antimould activity\\u000a varied greatly among the strains and was mainly detected within obligately heterofermentative Lactobacillus spp. Among these, Lb. sanfrancisco CB1 had the largest spectrum. It inhibited moulds related to bread spoilage such as Fusarium, Penicillium, Aspergillus and Monilia. A mixture of acetic, caproic, formic, propionic, butyric

A. Corsetti; M. Gobbetti; J. Rossi; P. Damiani

1998-01-01

324

Capacity of Human Nisin and Pediocin-Producing Lactic Acid Bacteria To Reduce Intestinal Colonization by Vancomycin-Resistant Enterococci  

Microsoft Academic Search

This study demonstrated the capacity of bacteriocin-producing lactic acid bacteria (LAB) to reduce intes- tinal colonization by vancomycin-resistant enterococci (VRE) in a mouse model. Lactococcus lactis MM19 and Pediococcus acidilactici MM33 are bacteriocin producers isolated from human feces. The bacteriocin secreted by P. acidilactici is identical to pediocin PA-1\\/AcH, while PCR analysis demonstrated that L. lactis harbors the nisin Z

Mathieu Millette; Gilbert Cornut; Claude Dupont; Francois Shareck; Denis Archambault; Monique Lacroix

2008-01-01

325

Isolation of lactic acid bacteria with inhibitory activity against pathogens and spoilage organisms associated with fresh meat  

Microsoft Academic Search

The use of lactic acid bacteria (LAB) as protective cultures in vacuum-packed chill-stored meat has potential application for assuring and improving food quality, safety and market access. In a study to identify candidate strains suitable for evaluation in a meat model, agar-based methods were employed to screen 181 chilled meat and meat process-related LAB for strains inhibitory to pathogens and

Rhys J. Jones; Hassan M. Hussein; Monique Zagorec; Gale Brightwell; John R. Tagg

2008-01-01

326

Use of Starter Cultures of Lactic Acid Bacteria and Yeasts in the Preparation of Kisra, a Sudanese Fermented Food  

Microsoft Academic Search

This research was carried out to study the effect of lactic acid bacteria (Lactobacillus fermentum, Lactobacillus brevis and Lactobacillus amylovorus) starter on traditional fermentation of sorghum flour (variety dabar). Results obtained indicated that fermentation time was reduced from 19-6 h albeit the final pH was reduced to 3.47. The addition of Saccharomyces cerevisiae to the previous starter further reduced sorghum

Asmahan A. Ali; Muna M. Mustafa

2009-01-01

327

Analysis of lactic acid bacteria populations during spontaneous malolactic fermentation of Tempranillo wines at five wineries during two consecutive vintages  

Microsoft Academic Search

The ecology and the population dynamics of lactic acid bacteria during malolactic fermentation of Tempranillo wine made at five wineries in Castilla-La Mancha were analysed for two consecutive vintages (years 2006 and 2007). This microbiota was typed using Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) subsequently identified using both molecular and phenotypic methods. Oenococcus oeni was the predominant species. Genotypes

P. Ruiz; P. M. Izquierdo; S. Seseña; M. Ll. Palop

2010-01-01

328

Variations in the energy metabolism of biotechnologically relevant heterofermentative lactic acid bacteria during growth on sugars and organic acids  

Microsoft Academic Search

Heterofermentative lactic acid bacteria (LAB) such as Leuconostoc, Oenococcus, and Lactobacillus strains ferment pentoses by the phosphoketolase pathway. The extra NAD(P)H, which is produced during growth on hexoses, is transferred to acetyl-CoA, yielding ethanol. Ethanol fermentation represents the limiting step in hexose fermentation, therefore, part of the extra NAD(P)H is used to produce erythritol and glycerol. Fructose, pyruvate, citrate, and

T. Zaunmüller; M. Eichert; H. Richter; G. Unden

2006-01-01

329

Identification and antagonistic activity of lactic acid bacteria occurring in porcine blood from industrial slaughterhouses—a preliminary study  

Microsoft Academic Search

Ninety-seven lactic acid bacteria (LAB) were isolated from slaughterhouse porcine blood in order to select autochthonous LAB strains for use as biopreservatives of this by-product. They were identified by 16S rDNA sequencing; and their inhibition capacity was determined against four bacterial species frequently found in contaminated blood, i.e. Staphylococcus aureus, Escherichia coli, Pseudomonas fluorescens and Bacillus spp. The taxonomic study

Eduard Dàvila; Lucero M. Zamora; Maria Pla; Carmen Carretero; Dolors Parés

2006-01-01

330

Glutamate dehydrogenase activity: a major criterion for the selection of flavour-producing lactic acid bacteria strains  

Microsoft Academic Search

Lactic acid bacteria (LAB) have the enzyme potential to transform amino acids into aroma compounds that contribute greatly to cheese flavour. Generally, amino acid conversion by LAB is limited by their low production of a-ketoglutarate since this a-ketoacid is essential for the first step of the conversion. Indeed, we have demonstrated that adding exogenous a-ketoglutarate to cheese curd, as well

Catherine Tanous; Agnieszka Kieronczyk; Sandra Helinck; Emilie Chambellon; Mireille Yvon

2002-01-01

331

Improvement of protein production in lactic acid bacteria using 5?-untranslated leader sequence of slpA from Lactobacillus acidophilus  

Microsoft Academic Search

The 5?-untranslated leader sequence (UTLS) of the slpA gene from Lactobacillus acidophilus contributes to mRNA stabilization by producing a 5? stem and loop structure, and a high-level expression system for the lactic acid bacteria was developed using the UTLS in this study. A plasmid, which expresses ?-amylase under the control of the ldh promoter, was constructed by integrating the core

Junya Narita; Saori Ishida; Kenji Okano; Sakurako Kimura; Hideki Fukuda; Akihiko Kondo

2006-01-01

332

Phylogenetic group- and species-specific oligonucleotide probes for single-cell detection of lactic acid bacteria in oral biofilms  

Microsoft Academic Search

BACKGROUND: The purpose of this study was to design and evaluate fluorescent in situ hybridization (FISH) probes for the single-cell detection and enumeration of lactic acid bacteria, in particular organisms belonging to the major phylogenetic groups and species of oral lactobacilli and to Abiotrophia\\/Granulicatella. RESULTS: As lactobacilli are known for notorious resistance to probe penetration, probe-specific assay protocols were experimentally

Beatrice Quevedo; Elin Giertsen; Vincent Zijnge; Helga Lüthi-Schaller; Bernhard Guggenheim; Thomas Thurnheer; Rudolf Gmür

2011-01-01

333

Application of PCR-DGGE for the identification of lactic acid bacteria in acitve dry wine yeasts  

Microsoft Academic Search

In this work a Polymerase Chain Reaction (PCR)-Denaturing Gradient Gel Electrophoresis (DGGE) protocol was used to identify\\u000a the Lactic Acid Bacteria (LAB) contaminants in enological active dry yeasts routinely used in the wine production. The method\\u000a is based on the PCR amplification of a DNA fragment from the region V1 of 16S rDNA gene followed by a DGGE technique. The

Cristina Giusto; Dagmara Medrala; Giuseppe Comi; Marisa Manzano

2007-01-01

334

Improvement of Experimentally Induced Hepatic and Renal Disorders in Rats using Lactic Acid Bacteria-fermented Soybean Extract (Biofermentics™)  

Microsoft Academic Search

The effects of lactic acid bacteria-fermented soybean extract (BiofermenticsTM; BF) on experimental models of hepatic and renal disorders were investigated in vivo and in vitro. In rat, hepatitis induced by feeding of deoxycholic acid (DCA, 0.5 wt\\/wt, n = 6) or intraperitoneal injection of D-galactosamine (GMN, 500 mg\\/body wt, n = 6), the increase in serum AST (aspartate aminotransferase) and

Ryoichi Shin; Momoyo Suzuki; Takeo Mizutani; Nobuyuki Susa

2009-01-01

335

In Vitro Reduction of Aflatoxin B1 by Strains of Lactic Acid Bacteria Isolated from Moroccan Sourdough Bread  

Microsoft Academic Search

The ability of some selected strains of lactic acid bacteria isolated from traditional sourdough ferments to remove aflatoxin B1 (AFB1) was studied in the present investigation. Isolates were grown for 48 h in MRS broth containing a known concentration of AFB1 at 30°C. The AFB1 in the medium was determined for each strain with HPLC and calculated with the initial

ABDELLAH ZINEDINE; MOHAMED FAID; MOHAMED BENLEMLIH

336

Phylogenetic Diversity of Lactic Acid Bacteria Associated with Paddy Rice Silage as Determined by 16S Ribosomal DNA Analysis  

Microsoft Academic Search

A total of 161 low-GC-content gram-positive bacteria isolated from whole-crop paddy rice silage were classified and subjected to phenotypic and genetic analyses. Based on morphological and biochemical char- acters, these presumptive lactic acid bacterium (LAB) isolates were divided into 10 groups that included members of the genera Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, and Weissella. Analysis of the 16S ribosomal DNA

Saïd Ennahar; Yimin Cai; Yasuhito Fujita

2003-01-01

337

Tina wooden vat biofilm: a safe and highly efficient lactic acid bacteria delivering system in PDO Ragusano cheese making.  

PubMed

In the Sicilian PDO Ragusano cheese making, raw milk is placed in a wooden vat called a Tina. As no starter is added, lactic acid is produced by milk flora and flora released from the Tina biofilm. The aim of this work was to assess the safety and efficiency of this natural inoculation system. From 15 Tinas' biofilms, bacteria total counts varied from 10(3) to 10(6) CFU/cm(2), with the predominance of thermophilic lactic acid bacteria. Low counts of yeasts and moulds were found in a few Tinas. Salmonella, Listeria monocytogenes, Escherichia coli O157:H7 were totally absent, as assessed by conventional plating and the Bax detection system after enrichment, highlighting the safety of the system. From four Tinas out of the 15, micropieces of wood were observed by confocal and scanning electron microscopy. The biofilm entrapped in a matrix covered almost entirely the surface of the wood. Polysaccharides were detected in the four Tinas. In three of the latter, cocci were predominant in the ecosystem whereas in the other one, cocci, bacilli, yeasts and moulds were observed. Fifty litres of microfiltrated milk (<10 CFU/mL) were poured in the four Tinas for 10 min of contact. Enumeration of lactic acid bacteria, yeasts and enterococci were performed in the milk after contact. Depending on the Tina, from 5.10(4) to 10(6) CFU/mL of Streptococcus thermophilus were released into the milk, and from 10(4) to 10(5) CFU/mL of thermophilic lactobacilli. Spontaneous acidification after contact confirmed the high efficiency of biofilm lactic acid bacteria delivery. PMID:19361876

Lortal, Sylvie; Di Blasi, Annalisa; Madec, Marie-Noëlle; Pediliggieri, Concetta; Tuminello, Laura; Tanguy, Gaëlle; Fauquant, Jacques; Lecuona, Yohan; Campo, Patrizia; Carpino, Stefania; Licitra, Giuseppe

2009-03-09

338

Ecology and technological capability of lactic acid bacteria isolated during Grillo grape vinification in the Marsala production area  

Microsoft Academic Search

Grapes of the “Grillo” variety, used to produce Marsala wine, were harvested from five vineyards with different climatic and\\u000a agronomic parameters, in order to obtain a first mapping of lactic acid bacteria (LAB) inhabiting the production area. Marsala\\u000a base wine production was followed at a large-scale, and also two experimental vinifications, with different lysozyme and SO2 concentrations and in combination,

Nicola Francesca; Luca Settanni; Ciro Sannino; Maria Aponte; Giancarlo Moschetti

2011-01-01

339

Dynamics of Indigenous Lactic Acid Bacteria Populations in Wine Fermentations from La Rioja (Spain) During Three Vintages  

Microsoft Academic Search

Diversity of lactic acid bacteria (LAB) species has been analyzed for three consecutive years (2006, 2007, and 2008) during\\u000a alcoholic and malolactic fermentations of Tempranillo wine in a winery at La Rioja. The results showed differences in malolactic\\u000a fermentation duration, and in both diversity of LAB species and diversity of Oenococcus oeni genotypes. O. oeni was shown to be the

Lucía González-Arenzana; Rosa López; Pilar Santamaría; Carmen Tenorio; Isabel López-Alfaro

340

Enzyme activities of lactic acid bacteria from a pearl millet fermented gruel ( ben-saalga) of functional interest in nutrition  

Microsoft Academic Search

Lactic acid bacteria responsible for the fermentation of a pearl-millet based fermented gruel, ben-saalga, were investigated for enzyme activity in relation with the nutritional characteristics of gruels used as complementary foods for young children. Thirty pre-selected LAB from a set of 155 isolates were characterized principally for their ability to produce amylase, phytase and ?-galactosidase. Two Lactobacillus plantarum strains (4.4

L. T. Songré-Ouattara; C. Mouquet-Rivier; C. Icard-Vernière; C. Humblot; B. Diawara; J. P. Guyot

2008-01-01

341

Development and quality of a Brazilian semi-hard goat cheese (coalho) with added probiotic lactic acid bacteria.  

PubMed

The effects of the addition of different strains of lactic acid bacteria on different quality parameters of a Brazilian goat semi-hard cheese (coalho) were assessed during 7 days of storage (10°C) as follows: Control, Lactobacillus lactis subsp. lactis and L. lactis subsp. cremoris (standard); C2, L. acidophilus; C3, L. paracasei; C4, Bifidobacterium lactis; and C5, L. acidophilus, L. paracasei and B. lactis. There were no differences for the proteolysis index and depth of proteolysis among the assessed cheeses. The cheeses presented increase in hardness, gumminess and chewiness during the storage. Regarding the ability to melt, all evaluated cheeses showed a reduction in diameter. Cheeses presented high luminosity with predominance of the yellow component; and number of lactic bacteria greater than 10?-10? cfu/g during the 7 days of storage. C5 had better sensory scores in the acceptance test, purchase intention and preference ranking test. Coalho goat cheese could be a potential carrier of probiotic lactic acid bacteria. PMID:22574688

Garcia, Estefânia Fernandes; de Oliveira, Maria Elieidy Gomes; Queiroga, Rita de Cássia Ramos Do Egypto; Machado, Tamires Alcântara Dourado; de Souza, Evandro Leite

2012-05-11

342

Purple Sulfur Bacteria Control the Growth of Aerobic Heterotrophic Bacterioplankton in a Meromictic Salt Lake  

PubMed Central

In meromictic Mahoney Lake, British Columbia, Canada, the heterotrophic bacterial production in the mixolimnion exceeded concomitant primary production by a factor of 7. Bacterial growth rates were correlated neither to primary production nor to the amount of chlorophyll a. Both results indicate an uncoupling of bacteria and phytoplankton. In the chemocline of the lake, an extremely dense population of the purple sulfur bacterium Amoebobacter purpureus is present year round. We investigated whether anoxygenic phototrophs are significant for the growth of aerobic bacterioplankton in the overlaying water. Bacterial growth rates in the mixolimnion were limited by inorganic phosphorus or nitrogen most of the time, and the biomass of heterotrophic bacteria did not increase until, in autumn, 86% of the cells of A. purpureus appeared in the mixolimnion because of their reduced buoyant density. The increase in heterotrophic bacterial biomass, soluble phosphorus concentrations below the detection limit, and an extraordinarily high activity of alkaline phosphatase in the mixolimnion indicate a rapid liberation of organically bound phosphorus from A. purpureus cells accompanied by a simultaneous incorporation into heterotrophic bacterioplankton. High concentrations of allochthonously derived dissolved organic carbon (mean, 60 mg of C(middot)liter(sup-1)) were measured in the lake water. In Mahoney Lake, liberation of phosphorus from upwelling purple sulfur bacteria and degradation of allochthonous dissolved organic carbon as an additional carbon source render heterotrophic bacterial production largely independent of the photosynthesis of phytoplankton. A recycling of inorganic nutrients via phototrophic bacteria also appears to be relevant in other lakes with anoxic bottom waters.

Overmann, J.; Beatty, J. T.; Hall, K. J.

1996-01-01

343

Lactic acid bacteria fermentation of human milk oligosaccharide components, human milk oligosaccharides and galactooligosaccharides.  

PubMed

Human milk contains about 7% lactose and 1% human milk oligosaccharides (HMOs) consisting of lactose with linked fucose, N-acetylglucosamine and sialic acid. In infant formula, galactooligosaccharides (GOSs) are added to replace HMOs. This study investigated the ability of six strains of lactic acid bacteria (LAB), Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus reuteri, Streptococcus thermophilus and Leuconostoc mesenteroides subsp. cremoris, to digest HMO components, defined HMOs, and GOSs. All strains grew on lactose and glucose. N-acetylglucosamine utilization varied between strains and was maximal in L. plantarum; fucose utilization was low or absent in all strains. Both hetero- and homofermentative LAB utilized N-acetylglucosamine via the Embden-Meyerhof pathway. Lactobacillus acidophilus and L. plantarum were the most versatile in hydrolysing pNP analogues and the only strains releasing mono- and disaccharides from defined HMOs. Whole cells of all six LAB hydrolysed oNP-galactoside and pNP-galactoside indicating ?-galactosidase activity. High ?-galactosidase activity of L. reuteri, L. fermentum, S. thermophilus and L. mesenteroides subsp. cremoris whole cells correlated to lactose and GOS hydrolysis. Hydrolysis of lactose and GOSs by heterologously expressed ?-galactosidases confirmed that LAB ?-galactosidases are involved in GOS digestion. In summary, the strains of LAB used were not capable of utilizing complex HMOs but metabolized HMO components and GOSs. PMID:21175746

Schwab, Clarissa; Gänzle, Michael

2010-12-22

344

Production of natural folates by lactic acid bacteria starter cultures isolated from artisanal Argentinean yogurts.  

PubMed

Folate is a B-group vitamin that cannot be synthesized by humans and must be obtained exogenously. Although some species of lactic acid bacteria (LAB) can produce folates, little is known about the production of this vitamin by yogurt starter cultures. Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains were isolated from artisanal Argentinean yogurts and were grown in folate-free culture medium (FACM) and nonfat milk after which intracellular and extracellular folate production were evaluated. From the initial 92 isolated LAB strains, 4 L. delbrueckii subsp. bulgaricus and 32 S. thermophilus were able to grow in the absence of folate. Lactobacillus delbrueckii subsp. bulgaricus CRL 863 and S. thermophilus CRL 415 and CRL 803 produced the highest extracellular folate levels (from 22.3 to 135 µg/L) in FACM. In nonfat milk, these strains were able to increase the initial folate concentrations by almost 190%. This is the first report where native strains of L. delbrueckii subsp. bulgaricus were shown to produce natural folate. The LAB strains identified in this study could be used in developing novel fermented products bio-enriched in natural folates that could in turn be used as an alternative to fortification with the controversial synthetic chemical folic acid. PMID:22502809

Laiño, Jonathan Emiliano; Leblanc, Jean Guy; Savoy de Giori, Graciela

2012-04-13

345

Effect of grape polyphenols on lactic acid bacteria and bifidobacteria growth: resistance and metabolism.  

PubMed

Food polyphenols are able to selectively modify the growth of susceptible micro-organisms. This study describes the effect of a flavan-3-ol enriched grape seed extract (GSE) on the growth of several lactic acid bacteria (LAB) and bifidobacteria and the ability of the resistant strains to metabolize these compounds. Streptococcus thermophilus, Lactobacillus fermentum, Lactobacillus acidophilus and Lactobacillus vaginalis strains showed a remarkable sensitivity to the phenolic extracts assayed, including a GSE fraction consisting mainly in (+)-catechin and (-)-epicatechin (GSE-M). On the other hand, Lactobacillus plantarum, Lactobacillus casei, and Lactobacillus bulgaricus strains reached maximal growth with the GSE fractions, including a rich-oligomeric (GSE-O) fraction. Within bifidobacteria, Bifidobacterium lactis BB12 showed the highest sensitivity to the phenolic extracts assayed, whereas Bifidobacterium breve 26M2 and Bifidobacterium bifidum HDD541 reached maximum growth in presence of GSE-O and GSE-M fractions. Metabolism of flavan-3-ols by LAB and bifidobacteria resistant strains was investigated in vitro. The results revealed that only L. plantarum IFPL935 was able to metabolize the polyphenols studied by means of galloyl-esterase, decarboxylase and benzyl alcohol dehydrogenase activities that led to the formation of gallic acid, pyrogallol and catechol, respectively. An unknown metabolite that does not exhibit a phenolic-acid-type structure was also detected, which suggests a new enzyme activity in L. plantarum IFPL935 able to degrade flavan-3-ol monomers. PMID:21839384

Tabasco, Raquel; Sánchez-Patán, Fernando; Monagas, María; Bartolomé, Begoña; Victoria Moreno-Arribas, M; Peláez, Carmen; Requena, Teresa

2011-06-12

346

The effect of marination on lactic acid bacteria communities in raw broiler fillet strips  

PubMed Central

Marination with marinade containing salt, sugar, and acetic acid is commonly used in Finland to enhance the value of raw broiler meat. In this study, we investigated the effect of marination, marinade components and storage time on composition of bacterial communities in modified atmosphere-packaged (MAP) broiler fillet strips. The communities were characterized using two culture-independent methods: 16S rRNA gene fragment sequencing and terminal restriction fragment length polymorphism. In unmarinated broiler fillet strips, Lactococcus spp. and Carnobacterium spp. predominated at the early storage phase but were partially replaced by Lactobacillus spp. and Leuconostoc spp. when the chilled storage time was extended. In the marinated fillet strips, Lactobacillus spp. and Leuconostoc spp. predominated independent from the storage time. By mixing the different marinade components with broiler meat, we showed that marination changed the community composition and favored Leuconostoc spp. and Lactobacillus spp. by the combined effect of carbohydrates and acetic acid in marinade. Marination increased the maximum level of lactic acid bacteria in broiler meat and enhanced CO2 production and acidification of meat during the chilled storage. Accumulation of CO2 in package head-space due to the enhanced growth of Leuconostoc spp. in marinated meat may lead to bulging of packages, which is a spoilage defect frequently associated with marinated and MAP raw broiler preparations in Finland.

Nieminen, T. T.; Valitalo, H.; Sade, E.; Paloranta, A.; Koskinen, K.; Bjorkroth, J.

2012-01-01

347

Occurrence of biogenic amine-forming lactic acid bacteria in wine and cider.  

PubMed

A collection of 810 lactic acid bacteria (LAB) strains isolated from wine and cider was screened for potential biogenic amine (BA) producers by combining molecular and phenotypic approaches. A newly developed multiplex PCR method allowed for the simultaneous detection of four genes involved in the production of histamine (histidine decarboxylase, hdc), tyramine (tyrosine decarboxylase, tyrdc) and putrescine (via either ornithine decarboxylase, odc, or agmatine deiminase, agdi) while TLC and HPLC analysis allowed for BA-production determination. One hundred and fifty-eight LAB strains were monitored by the molecular/phenotypic double approach and revealed a good correlation between genotypic and phenotypic data. Eighteen per cent of the tested strains were positive for at least one BA target gene with up to three detected simultaneously, in particular amongst Lactobacillus brevis and Lactobacillus hilgardii isolates for the tyrdc and agdi genes. The most frequent gene corresponded to the agdi gene detected in 112 strains (14% of all LAB strains) of 10 different LAB species. The tyrdc gene was detected in 67 strains represented by 7 different LAB species (8% overall), especially those isolated from wine. Lower levels of hdc(+) (2% of strains) and especially odc(+) (0.5% of strains) strains were observed. Interestingly, species that have never been described to carry BA-producing pathway genes were identified in this study. Furthermore, only one cadaverine-producer was detected and corresponded to Lactobacillus 30a, a collection strain not found in fermented beverages, although cadaverine is commonly detected in wines. PMID:20832688

Coton, M; Romano, A; Spano, G; Ziegler, K; Vetrana, C; Desmarais, C; Lonvaud-Funel, A; Lucas, P; Coton, E

2010-07-16

348

Risk assessment of genetically modified lactic acid bacteria using the concept of substantial equivalence.  

PubMed

The use of food-grade microorganisms such as lactic acid bacteria (LAB) is one of the most promising methods for delivering health promoting compounds. Since it is not always possible to obtain strains that have the ability to produce specific compounds naturally or that produce them in sufficient quantities to obtain physiological responses, genetic modifications can be performed to improve their output. The objective of this study was to evaluate if previously studied genetically modified LAB (GM-LAB), with proven in vivo beneficial effects, are just as safe as the progenitor strain from which they were derived. Mice received an elevated concentration of different GM-LAB or the native parental strain from which they were derived during a prolonged period of time, and different health parameters were evaluated. Similar growth rates, hematological values, and other physiological parameters were obtained in the animals that received the GM-LAB compared to those that were fed with the native strain. These results demonstrate that the GM-LAB used in this study are just as safe as the native strains from which they were derived and thus merit further studies to include them into the food chain. PMID:20449592

LeBlanc, Jean Guy; Van Sinderen, Douwe; Hugenholtz, Jeroen; Piard, Jean-Christophe; Sesma, Fernando; de Giori, Graciela Savoy

2010-05-07

349

Immunomodulatory properties of fermented soy and dairy milks prepared with lactic acid bacteria.  

PubMed

Fermented soy and dairy milk preparations provide a means for delivering lactic acid bacteria and their fermentation products into the diet. Our aims were to test immunomodulatory bioactivity of fermented soy beverage (SB) and dairy milk blend (MB) preparations on human intestinal epithelial cells (IEC) and to determine the impact of freezing medium on culture survival prior to bioactivity analyses. Fermented SB and MB were prepared using pure or mixed cultures of Streptococcus thermophilus ST5, Bifidobacterium longum R0175, and Lactobacillus helveticus R0052. Immunomodulatory bioactivity was assessed by testing selected SB and MB ferments on tumor necrosis factor alpha (TNFalpha)-treated IEC and measuring effects on Interleukin-8 (IL-8) production. Impact of timing of ferment administration relative to this pro-inflammatory challenge was investigated. The most pronounced reductions in IEC IL-8 production were observed when IEC were treated with either SB or MB ferment preparations prior to TNFalpha challenge. These results indicate that freezing-stable MB and SB ferments prepared with selected strains can modulate IEC IL-8 production in vitro, and suggest that yogurt-like fermented soy formulations could provide a functional food alternative to milk-based fermented products. PMID:19799669

Wagar, L E; Champagne, C P; Buckley, N D; Raymond, Y; Green-Johnson, J M

2009-10-01

350

Characterization of lactic acid bacteria isolated from Bukuljac, a homemade goat's milk cheese.  

PubMed

The Bukuljac cheese is traditionally homemade cheese, produced from heat-treated goat's milk without the addition of any bacterial starter culture. The presence of lactic acid bacteria (LAB) in Bukuljac cheese has been analyzed by using a polyphasic approach including microbiological and molecular methods such as rep-PCR with (GTG)5 primer. Lactobacillus paracasei subsp. paracasei represents a dominant strain in the microflora of analyzed cheese. Out of 55 Gram-positive and catalase-negative isolates, 48 belonged to L. paracasei subsp. paracasei species. Besides lactobacilli, five Lactococcus lactis subsp. lactis and two Enterococcus faecalis were found. Results of PCR-denaturing gradient gel electrophoresis (DGGE) of DNA extracted directly from the fresh cheese revealed the presence of Leuconostoc mesenteroides. Only lactobacilli showed a high proteolytic activity and hydrolyzed alpha(s1)- and beta-caseins. They are also producers of diacetyl. In addition, 34 out of 55 isolates, all determined as lactobacilli, showed the ability of auto-aggregation. Among 55 isolates, 50 also exhibited antimicrobial activity. PMID:18177967

Nikolic, Milica; Terzic-Vidojevic, Amarela; Jovcic, Branko; Begovic, Jelena; Golic, Natasa; Topisirovic, Ljubisa

2007-12-04

351

Symbionts as Major Modulators of Insect Health: Lactic Acid Bacteria and Honeybees  

PubMed Central

Lactic acid bacteria (LAB) are well recognized beneficial host-associated members of the microbiota of humans and animals. Yet LAB-associations of invertebrates have been poorly characterized and their functions remain obscure. Here we show that honeybees possess an abundant, diverse and ancient LAB microbiota in their honey crop with beneficial effects for bee health, defending them against microbial threats. Our studies of LAB in all extant honeybee species plus related apid bees reveal one of the largest collections of novel species from the genera Lactobacillus and Bifidobacterium ever discovered within a single insect and suggest a long (>80 mya) history of association. Bee associated microbiotas highlight Lactobacillus kunkeei as the dominant LAB member. Those showing potent antimicrobial properties are acquired by callow honey bee workers from nestmates and maintained within the crop in biofilms, though beekeeping management practices can negatively impact this microbiota. Prophylactic practices that enhance LAB, or supplementary feeding of LAB, may serve in integrated approaches to sustainable pollinator service provision. We anticipate this microbiota will become central to studies on honeybee health, including colony collapse disorder, and act as an exemplar case of insect-microbe symbiosis.

Vasquez, Alejandra; Forsgren, Eva; Fries, Ingemar; Paxton, Robert J.; Flaberg, Emilie; Szekely, Laszlo

2012-01-01

352

Manufacture and characterization of functional emmer beverages fermented by selected lactic acid bacteria.  

PubMed

Autochthonous lactic acid bacteria from emmer flour were screened based on the kinetic of acidification and used to ferment beverages containing emmer flour, emmer gelatinized flour, and emmer malt at percentages ranging 5-30% (wt/wt). Preliminarily, the concentration of raw flour and malt was selected based on sensory analysis. Different protocols were set up for the manufacture of four different beverages which used Lactobacillus plantarum 6E as the starter. Emmer beverages were mainly differentiated based on the concentration of organic acids, carbohydrates, amino acids, dietary fibers, vitamins, antioxidant and phytase activities, and volatiles and sensory profiles. Wheat flour bread was used as the control to determine the hydrolysis index (HI=100), as an indirect estimation of the glycemic index. The beverage made with 30% (wt/wt) of gelatinized flour showed an HI of 56%, its viscosity was improved by using an EPS-producing strain and it allowed the survival of the potential probiotic Lactobacillus rhamnosus SP1 at cell density of ca. 5 × 10(8) cfu/ml throughout storage at 4 °C. Among the exploited biotechnological options, this latter beverage could be considered as a promising novel functional food. PMID:21356461

Coda, Rossana; Rizzello, Carlo Giuseppe; Trani, Antonio; Gobbetti, Marco

2010-11-12

353

Characterization of lactic acid bacteria isolated from the one humped camel milk produced in Morocco.  

PubMed

One hundred and twenty (120) strains of lactic acid bacteria (LAB) were enumerated and isolated from raw dromedary milk in Morocco using various cultured media. Strains isolated were characterized by phenotypic, physiological and biochemical properties. Results showed that high counts of LAB were found. Presumptive lactobacilli counts ranged from 2.5x10(2) to 6x10(7)cfu/ml, presumptive lactococci levels varied from 5x10(2) to 6x10(7)cfu/ml, presumptive streptococci counts varied from 4.2x10(2) to 8x10(7)cfu/ml, presumptive leuconostoc levels ranged from 5.4x10(2) to 5.4x10(7)cfu/ml. Results showed also that Lactobacillus and Lactococcus were the predominant genera with 37.5% and 25.8%, respectively. The dominated species found were Lactococcus lactis subsp. lactis (17.5%), Lactobacillus helveticus (10%), Streptococcus salivarius subsp. thermophilus (9.20%), Lactobacillus casei subsp. casei (5.80%) and Lactobacillus plantarum (5%). This is the first report on the characterization of LAB strains isolated from the one humped camel milk produced in Morocco. PMID:17187971

Khedid, K; Faid, M; Mokhtari, A; Soulaymani, A; Zinedine, A

2006-12-21

354

Evidence of Two Functionally Distinct Ornithine Decarboxylation Systems in Lactic Acid Bacteria  

PubMed Central

Biogenic amines are low-molecular-weight organic bases whose presence in food can result in health problems. The biosynthesis of biogenic amines in fermented foods mostly proceeds through amino acid decarboxylation carried out by lactic acid bacteria (LAB), but not all systems leading to biogenic amine production by LAB have been thoroughly characterized. Here, putative ornithine decarboxylation pathways consisting of a putative ornithine decarboxylase and an amino acid transporter were identified in LAB by strain collection screening and database searches. The decarboxylases were produced in heterologous hosts and purified and characterized in vitro, whereas transporters were heterologously expressed in Lactococcus lactis and functionally characterized in vivo. Amino acid decarboxylation by whole cells of the original hosts was determined as well. We concluded that two distinct types of ornithine decarboxylation systems exist in LAB. One is composed of an ornithine decarboxylase coupled to an ornithine/putrescine transmembrane exchanger. Their combined activities results in the extracellular release of putrescine. This typical amino acid decarboxylation system is present in only a few LAB strains and may contribute to metabolic energy production and/or pH homeostasis. The second system is widespread among LAB. It is composed of a decarboxylase active on ornithine and l-2,4-diaminobutyric acid (DABA) and a transporter that mediates unidirectional transport of ornithine into the cytoplasm. Diamines that result from this second system are retained within the cytosol.

Romano, Andrea; Trip, Hein; Lonvaud-Funel, Aline; Lolkema, Juke S.

2012-01-01

355

"Green preservatives": combating fungi in the food and feed industry by applying antifungal lactic acid bacteria.  

PubMed

Fungal food spoilage plays a pivotal role in the deterioration of food and feed systems and some of them are also able to produce toxic compounds for humans and animals. The mycotoxins produced by fungi can cause serious health hazards, including cancerogenic, immunotoxic, teratogenic, neurotoxic, nephrotoxic and hepatotoxic effects, and Kashin-Beck disease. In addition to this, fungal spoilage/pathogens are causing losses of marketable quality and hygiene of foodstuffs, resulting in major economic problem throughout the world. Nowadays, food spoilage can be prevented using physical and chemical methods, but no efficient strategy has been proposed so far to reduce the microbial growth ensuring public health. Therefore, lactic acid bacteria (LAB) can play an important role as natural preservatives. The protection of food products using LAB is mainly due to the production of antifungal compounds such as carboxylic acids, fatty acids, ethanol, carbon dioxide, hydrogen peroxide, and bacteriocins. In addition to this, LAB can also positively contribute to the flavor, texture, and nutritional value of food products. This review mainly focuses on the use of LAB for food preservation given their extensive industrial application in a wide range of foods and feeds. The attention points out the several industrial patents concerning the use of antifungal LAB as biocontrol agent against spoilage organisms in different fermented foods and feeds. PMID:22909981

Pawlowska, Agata M; Zannini, Emanuele; Coffey, Aidan; Arendt, Elke K

2012-01-01

356

A 'bacteriocin PCR array' for identification of bacteriocin-related structural genes in lactic acid bacteria.  

PubMed

Bacteriocins have been identified in many strains of lactic acid bacteria (LAB) which are a source of natural food preservatives and microbial inhibitors. Our objectives were to use a PCR array of primers to identify bacteriocin structural genes in Bac(+) LAB. DNA sequence homology at the 5'- and 3'-ends of the various structural genes indicated that non-specific priming may allow PCR amplification of heterologous bacteriocin genes. Successful amplification was obtained by real-time PCR and confirmed by melting curve and agarose gel analysis. Sequence information specific to targeted bacteriocin structural genes from the intra-primer regions of amplimers was compared to sequences residing in GenBank. The bacteriocin PCR array allowed the successful amplification of bacteriocin structural genes from strains of Lactobacillus, Lactococcus, and Pediococcus including one whose amino acid sequence was unable to be determined by Edman degradation analysis. DNA sequence analysis identified as many as 3 bacteriocin structural genes within a given strain, identifying ten unique bacteriocin sequences that were previously uncharacterized (partial homology) and one that was 100% identical to sequences in GenBank. This study provides a rapid approach to sequence and identify bacteriocin structural genes among Bac(+) LAB using a microplate bacteriocin PCR array. PMID:22119852

Macwana, Sunita J; Muriana, Peter M

2011-11-18

357

Cholesterol removal capability of lactic acid bacteria and related cell membrane fatty acid modifications.  

PubMed

Milk and dairy products play an important role in a healthy diet because of their high nutritional value, even if they represent a source of lipids and cholesterol. Nowadays, some commercially hypocholesterolemic products are available, which contain lactic acid bacteria (LAB). Therefore, the aims of this study were to test and compare the cholesterol removal abilities of different LAB species and to investigate the capacity of the cholesterol to change the cellular fatty acid composition of microorganisms. Fifty-eight strains of dairy LAB were studied for their ability to remove cholesterol during 24 h of growth. Two of them, L. plantarum 885 and L. acidophilus LA-5®, showed the higher reduction capability. For these strains, the cellular fatty acid composition was studied. They showed a different behaviour, which appeared related to the needs of the cells to maintain the characteristics of membrane fluidity, but was dependent upon their original fatty acid composition. Further studies are required to better characterise the LAB strains to be used to develop fermented dairy products with reduced cholesterol content or be able to induce hypocholesterolemic effects. It will also be interesting to investigate the possible modifications of the cell membrane caused by cholesterol and its possible involvement in cell metabolism. PMID:23386266

Remagni, Maria Chiara; Paladino, Maria; Locci, Francesco; Romeo, Flora V; Zago, Miriam; Povolo, Milena; Contarini, Giovanna; Carminati, Domenico

2013-02-06

358

Detection and characterization of pediocin PA-1/AcH like bacteriocin producing lactic acid bacteria.  

PubMed

Fifty-five bacteriocinogenic lactic acid bacteria (LAB) isolated from seven different sources. Eight isolates were found to produce pediocin PA-1 like bacteriocin as detected by pedB gene PCR and dot-blot hybridization. The culture filtrate (CF) activity of these isolates exhibited strong antilisterial, antibacterial activity against tested food-borne pathogens and LAB. The identification and genetic diversity among the selected LAB was performed by conventional morphological and molecular tools like RFLP, RAPD, and 16S rDNA gene sequencing. The isolates were identified as, 1 each of Pediococcus acidilactici Cb1, Lactobacillus plantarum Acr2, and Streptococcus equinus AC1, 2 were of P. pentosaceus Cb4 and R38, and other 3 were Enterococcus faecium Acr4, BL1, V3. Partial characterization of the bacteriocins revealed that the peptide was heat-stable, active at acidic to alkaline pH, inactivated by proteolytic enzymes, and had molecular weight around 4.6 kDa and shared the properties of class IIa pediocin-family. The bacteriocin production at different temperatures, pH, and salt concentrations was studied to investigate the optimal condition for application of these isolates as a starter culture or as a biopreservative in either acidic or non-acidic foods. PMID:21656248

Devi, S Manjulata; Halami, Prakash M

2011-06-09

359

Detection of mobile genetic elements in pediocin PA-1 like producing lactic acid bacteria.  

PubMed

To evaluate the presence of mobile genetic elements (MGEs) in intergeneric and interspecific pediocin producing lactic acid bacteria (LAB) the flanking regions of the pediocin PA-1/AcH (pediocin PA-1) operon was characterized. In Enterococcus faecium Acr4 and Lactobacillus plantarum Acr2 a variation in the amplicon size in the downstream region of the operon was identified, suggesting a deletion in this region. Beyond that, in pediocin PA-1 encoding plasmids MGEs such as ISLpl1 and mobilization regions were detected by Southern hybridization analysis. Phylogenetic analyses of the E. faecium Acr4 ISLpl1 gene sequence suggested the gene transfer from lactobacilli in the environment. The tyrosine recombinase detected in pediocin plasmids of Pediococcus acidilactici H and K7 indicate a possible transfer of the entire operon among LAB. Since these elements are known to be associated with transfer of genes linked to the bacteriocin production, antibiotic resistance, and sugar utilization, we suggest similar mechanism for natural spread of pediocin PA-1 operon among different bacterial species. PMID:22915312

Devi, Sundru Manjulata; Halami, Prakash M

2012-08-23

360

Screening of lactic acid bacteria for bacteriocins by microbiological and PCR methods.  

PubMed

We describe a practical laboratory designed for third-year undergraduate students of Biotechnology as part of a Microbial Physiology and Genetics course. It comprises a five-session laboratory module to screen foods for lactic acid bacteria (LAB)1 and to test isolated LAB for the presence of bacteriocins. Traditional Thai fermented foods are first screened for bacteriocin-producing LAB using microbiological methods. This is followed by a simple and rapid DNA extraction and by a multiplex polymerase chain reaction (PCR) using three pairs of specific primers to test for the presence or absence of various bacteriocin genes in the isolated LAB. PCR amplicons of 332, 412, and 608 bp indicate the presence of pediocin, enterocin, and nisin genes, respectively, whereas no amplicon band indicates the absence of these bacteriocins. The laboratory provides the students with experience in the use of microbiological and multiplex PCR methods and shows how the molecular biology techniques can be related to their daily lives. The module could easily be adapted to the study of fermented foods from other countries. PMID:21591125

Suwanjinda, Duongdearn; Eames, Chris; Panbangred, Watanalai

2007-09-01

361

Structural and rheological characterisation of heteropolysaccharides produced by lactic acid bacteria in wheat and sorghum sourdough.  

PubMed

Hydrocolloids improve the volume, texture, and shelf life of bread. Exopolysaccharides (EPS) produced by lactic acid bacteria (LAB) during sourdough fermentation can replace hydrocolloids. It was the aim of this study to determine whether heteropolysaccharides (HePS) synthesized intracellularly from sugar nucleotides by glycosyltransferases are produced in wheat and gluten-free sorghum sourdough at effective levels. The HePS-producing strains Lactobacillus casei FUA3185, L. casei FUA3186, and Lactobacillus buchneri FUA3154 were used; Weissella cibaria 10M producing no EPS in the absence of sucrose served as control strain. Cell suspensions of L. buchneri in MRS showed the highest viscosity at low shear rate. Glycosyltransferase genes responsible of HePS formation in LAB were expressed in sorghum and wheat sourdough. However, only HePS produced by L. buchneri influenced the rheological properties of sorghum sourdoughs but not of wheat sourdoughs. Sorghum sourdough fermented with L. buchneri exhibited a low |G*| compared to the control, indicating a decrease in resistance to deformation. An increase in tan ? indicated decreased elasticity. The use of LAB producing HePS expands the diversity of EPS and increases the variety of cultures for use in baking. PMID:21356463

Galle, Sandra; Schwab, Clarissa; Arendt, Elke K; Gänzle, Michael G

2010-11-19

362

The effect of marination on lactic acid bacteria communities in raw broiler fillet strips.  

PubMed

Marination with marinade containing salt, sugar, and acetic acid is commonly used in Finland to enhance the value of raw broiler meat. In this study, we investigated the effect of marination, marinade components and storage time on composition of bacterial communities in modified atmosphere-packaged (MAP) broiler fillet strips. The communities were characterized using two culture-independent methods: 16S rRNA gene fragment sequencing and terminal restriction fragment length polymorphism. In unmarinated broiler fillet strips, Lactococcus spp. and Carnobacterium spp. predominated at the early storage phase but were partially replaced by Lactobacillus spp. and Leuconostoc spp. when the chilled storage time was extended. In the marinated fillet strips, Lactobacillus spp. and Leuconostoc spp. predominated independent from the storage time. By mixing the different marinade components with broiler meat, we showed that marination changed the community composition and favored Leuconostoc spp. and Lactobacillus spp. by the combined effect of carbohydrates and acetic acid in marinade. Marination increased the maximum level of lactic acid bacteria in broiler meat and enhanced CO(2) production and acidification of meat during the chilled storage. Accumulation of CO(2) in package head-space due to the enhanced growth of Leuconostoc spp. in marinated meat may lead to bulging of packages, which is a spoilage defect frequently associated with marinated and MAP raw broiler preparations in Finland. PMID:23087685

Nieminen, T T; Välitalo, H; Säde, E; Paloranta, A; Koskinen, K; Björkroth, J

2012-10-18

363

The Effect of Lactic Acid Bacteria Isolates on the Urinary Tract Pathogens to Infants In Vitro  

PubMed Central

Urinary tract infections are common clinical problems in children, even though lots of treatment strategies have been tried. Many studies of the application of probiotics for urinary tract infection in female adults exist, but there is a lack of studies in children. The aims of this study were to screen probiotic strains for inhibiting the uropathogens in vitro, to find candidates for in vivo study. Nine strains of E. coli were isolated from children with urinary tract infection and six uropathogens were obtained from Korean Colletion for Type Cultures and American Type Culture Collection. Also 135 lactic acid bacteria (LAB) strains were isolated from healthy children, and were identified through physiologic, biochemical methods, 16S rDNA PCR, and data analysis. And with agar disk diffusion assay technique the antimicrobial activities of these LAB strains against those uropathogens were examined. Three strains of separated LAB strains demonstrated major antimicrobial activity against all the uropathogens. In the agar disk diffusion assay technique, antimicrobial activities increased most in the 4th day culture broth with separated Lactobacillus. In summary, some LAB can be used as candidates to develop the probiotic microorganisms that inhibit uropathogens in children, and are expected to be applied to treatment and prevention of pediatric urinary tract infection.

Lee, Ho Seok; Kim, Won Yong

2009-01-01

364

Effect of lactic acid bacteria inoculants on in vitro digestibility of wheat and corn silages.  

PubMed

The aim of the study was to determine the effect of 10 sources of lactic acid bacteria (LAB) on dry matter digestibility (DM-D) and neutral detergent fiber digestibility (NDF-D), in various combinations with starch, in vitro. The soluble starch represented a concentrate feed, whereas silage represented feeding only roughage. The DM-D and NDF-D were determined after 24 and 48 h of incubation to represent effective (24 h) and potential (48 h) digestibility. Addition of LAB was both by direct application of the inoculants to rumen fluid (directly fed microbials) and by the use of preinoculated silages. For each feed combination, tubes without added LAB served as controls. The results indicate that, overall, some LAB inoculants applied at ensiling or added directly to the rumen fluid had the potential to increase the DM-D and NDF-D. The major significant inoculant effect on NDF-D was obtained after 24 h of incubation, whereas the effect after 48 h was mainly nonsignificant. The effective inoculants seemed to minimize the inhibitory effect of the starch on NDF-D within 24 h, perhaps by competition with lactate-producing rumen microorganisms. PMID:17881698

Weinberg, Z G; Shatz, O; Chen, Y; Yosef, E; Nikbahat, M; Ben-Ghedalia, D; Miron, J

2007-10-01

365

Bio-protective potential of lactic acid bacteria isolated from fermented wax gourd.  

PubMed

The antifungal activities of 85 lactic acid bacteria strains isolated from fermented wax gourd against the four fungal species, Penicillium oxalicum, Aspergillus flavus, Aspergillus sydowii, and Mucor racemosus, were determined. Inhibitory activity against at least one or more fungal species was observed with 27 Weissella cibaria and 11 Weissella paramesenteroides strains. Among these strains, W. cibaria 861006 and W. paramesenteroides 860509 showed greater inhibitory activities and were therefore selected for further analysis. The results suggested that the antifungal activities were originated from the organic acids produced by W. cibaria 861006 and W. paramesenteroides 860509. The application tests indicated that the growth of P. oxalicum could be effectively inhibited by W. cibaria 861006 for 6 days on grape surfaces. However, W. paramesenteroides 860509 could only remain its inhibition effect for 48 h. The findings obtained in this study suggest the potential use of W. cibaria 861006 as a bio-protective agent against fungi for agricultural purposes or ready-to-eat fresh fruit and vegetable products. PMID:22307833

Lan, Wei-Tse; Chen, Yi-Sheng; Wu, Hui-Chung; Yanagida, Fujitoshi

2012-02-04

366

Potential of bacteriocin-producing lactic acid bacteria for improvements in food safety and quality.  

PubMed

Lactic acid bacteria (LAB) have been used for centuries in the fermentation of a variety of dairy products. The preservative ability of LAB in foods is attributed to the production of anti-microbial metabolites including organic acids and bacteriocins. Bacteriocins generally exert their anti-microbial action by interfering with the cell wall or the membrane of target organisms, either by inhibiting cell wall biosynthesis or causing pore formation, subsequently resulting in death. The incorporation of bacteriocins as a biopreservative ingredient into model food systems has been studied extensively and has been shown to be effective in the control of pathogenic and spoilage microorganisms. However, a more practical and economic option of incorporating bacteriocins into foods can be the direct addition of bacteriocin-producing cultures into food. This paper presents an overview of the potential for using bacteriocin-producing LAB in foods for the improvement of the safety and quality of the final product. It describes the different genera of LAB with potential as biopreservatives, and presents an up-to-date classification system for the bacteriocins they produce. While the problems associated with the use of some bacteriocin-producing cultures in certain foods are elucidated, so also are the situations in which incorporation of the bacteriocin-producer into model food systems have been shown to be very effective. PMID:12423803

O'Sullivan, L; Ross, R P; Hill, C

367

Biosorption of heavy metals by lactic acid bacteria and identification of mercury binding protein.  

PubMed

Heavy metals cause various health hazards. Using lactic acid bacteria (LAB), we tested the biosorption of heavy metals e.g. cadmium (Cd) (II), lead (Pb) (II), arsenic (As) (III), and mercury (Hg) (II). Cd (II) sorption was tested in 103 strains using atomic absorption spectrophotometery (AAS). Weissella viridescens MYU 205 (1 × 10(8) cells/ml) decreased Cd (II) levels in citrate buffer (pH 6.0) from one ppm to 0.459 ± 0.016 ppm, corresponding to 10.46 ?g of Cd (II). After screening, 11 LAB strains were tested using various pH (pH 4.0, 5.0, 6.0, 7.0) showing the sorption was acid sensitive; and was cell concentration dependent, where the Cd (II) concentration decreased from one ppm to 0.042 (max)/0.255 (min) ppm at 1 × 10(10) cells/ml. Additionally, the biosorption of Pb (II), As (III), and Hg (II) were tested using an inductively coupled plasma mass spectrometer (ICP-MS). The Hg (II) concentration was reduced the most followed by Pb (II) and As (III). Many of the bacterial cell surface proteins of W. viridescens MYU 205 showed binding to Hg (II) using the Hg (II) column assay. Having a CXXC motif, a ?14 kDa protein may be one of the Hg (II) binding proteins. LAB biosorption may aid the detoxification of people exposed to heavy metals. PMID:23603782

Kinoshita, Hideki; Sohma, Yui; Ohtake, Fumika; Ishida, Mitsuharu; Kawai, Yasushi; Kitazawa, Haruki; Saito, Tadao; Kimura, Kazuhiko

2013-04-17

368

The investigation of probiotic potential of lactic acid bacteria isolated from traditional Mongolian dairy products.  

PubMed

The aims of this study were to investigate the diversity of lactic acid bacteria (LAB) isolated from traditional Mongolian dairy products, and to estimate the probiotic potential of the isolated strains. We collected 66 samples of the traditional Mongolian dairy products tarag (n = 45), airag (n = 7), aaruul (n = 8), byasulag (n = 1) and eezgii (n = 5), from which 543 LAB strains were isolated and identified based on 16S ribosomal DNA sequence. The predominant species of those products were Lactobacillus (L.) delbrueckii ssp. bulgaricus, L. helveticus, L. fermentum, L. delbrueckii ssp. lactis and Lactococcus lactis ssp. lactis. However, we could not detect any LAB strains from eezgii. All LAB isolates were screened for tolerance to low pH and to bile acid, gas production from glucose, and adherence to Caco-2 cells. In vitro, we found 10 strains possess probiotic properties, and almost identified them as L. plantarum or L. paracasei subspecies, based on 16S ribosomal DNA and carbohydrate fermentation pattern. These strains were differentiated from each other individually by randomly amplified polymorphic DNA analysis. Additionally, it was notable that 6/10 strains were isolated from camel milk tarag from the Dornogovi province. PMID:21794017

Takeda, Shiro; Yamasaki, Keiko; Takeshita, Masahiko; Kikuchi, Yukiharu; Tsend-Ayush, Chuluunbat; Dashnyam, Bumbein; Ahhmed, Abdulatef M; Kawahara, Satoshi; Muguruma, Michio

2011-04-20

369

The characterisation of lactic acid bacteria during the fermentation of an artisan Serbian sausage (Petrovská Klobása).  

PubMed

Petrovská Klobása is an artisan Serbian sausage made only from meat and spices without any additives or starter cultures. In order to characterise lactic acid bacteria (LAB) microflora, a total number of 404 LAB strains were isolated from 15 samples collected during 90 days of the fermentation and 120 days of storage of one batch of Petrovská Klobása. The isolates were preliminarily identified by phenotypic tests and subjected to (GTG)?-PCR fingerprinting. Representatives of each group were identified by 16S rDNA sequencing. The results showed that among the isolates, Lactobacillus sakei and Leuconostoc mesenteroides predominate with 36.4% and 37.1% of total LAB strains, respectively. Pediococcus pentosaceus was also isolated in high proportion (18.4%) whereas Enterococcus durans and Enterococcus caseliflavus made only 1% and 6% of the total isolates, correspondingly. The analysis of vacuum packed and modified atmosphere packed (MAP) samples showed higher presence of L. mesenteroides and L. sakei in the total microflora. PMID:21420794

Danilovi?, Bojana; Jokovi?, Nataša; Petrovi?, Ljiljana; Veljovi?, Katarina; Tolina?ki, Maja; Savi?, D

2011-03-02

370

Inactivation of calcium-dependent lactic acid bacteria phages by phosphates.  

PubMed

The capacity of three phosphates to interrupt the lytic cycle of four specific autochthonal bacteriophages of lactic acid bacteria used as starters was assayed. The phosphates used (polyphosphates A and B and sodium tripolyphosphate-high solubility [TAS]) were selected on the basis of their capacity to sequester divalent cations, which are involved in the lytic cycle of certain bacteriophages. The assays were performed in culture media (deMan Rogosa Sharpe and Elliker broths) and reconstituted (10%, wt/vol) commercial skim milk to which phosphates had been added at concentrations of 0.1, 0.3, and 0.5% (wt/vol). Phosphate TAS was the most inhibitory one, since it was able to inhibit the lytic cycle of all bacteriophages studied, in both broths and milk. In broth, polyphosphates A and B inhibited the lytic cycle of only two bacteriophages at the maximal concentration used (0.5%), whereas in milk, they were not capable of maintaining the same inhibitory effect. PMID:17612087

Suárez, V B; Capra, M L; Rivera, M; Reinheimer, J A

2007-06-01

371

Symbionts as major modulators of insect health: lactic acid bacteria and honeybees.  

PubMed

Lactic acid bacteria (LAB) are well recognized beneficial host-associated members of the microbiota of humans and animals. Yet LAB-associations of invertebrates have been poorly characterized and their functions remain obscure. Here we show that honeybees possess an abundant, diverse and ancient LAB microbiota in their honey crop with beneficial effects for bee health, defending them against microbial threats. Our studies of LAB in all extant honeybee species plus related apid bees reveal one of the largest collections of novel species from the genera Lactobacillus and Bifidobacterium ever discovered within a single insect and suggest a long (>80 mya) history of association. Bee associated microbiotas highlight Lactobacillus kunkeei as the dominant LAB member. Those showing potent antimicrobial properties are acquired by callow honey bee workers from nestmates and maintained within the crop in biofilms, though beekeeping management practices can negatively impact this microbiota. Prophylactic practices that enhance LAB, or supplementary feeding of LAB, may serve in integrated approaches to sustainable pollinator service provision. We anticipate this microbiota will become central to studies on honeybee health, including colony collapse disorder, and act as an exemplar case of insect-microbe symbiosis. PMID:22427985

Vásquez, Alejandra; Forsgren, Eva; Fries, Ingemar; Paxton, Robert J; Flaberg, Emilie; Szekely, Laszlo; Olofsson, Tobias C

2012-03-12

372

Selectivity and antimicrobial action of bovine lactoferrin derived peptides against wine lactic acid bacteria.  

PubMed

In this study, the antibacterial activities of a bovine Lactoferrin pepsin hydrolysate (LFH) and a synthetic peptide derived from bovine lactoferricin (LfcinB(17-31)) have been evaluated against Oenococcus oeni and three additional lactic acid bacteria (LAB) known to cause spoilage during winemaking processes. Inhibition of bacterial growth was demonstrated in vitro in synthetic broth media (MRS) for both LFH and LfcinB(17-31). The bactericidal activity of the synthetic peptide was also assayed and found to vary depending on the bacterial species and the matrix in which exposure to peptide occurred (either MRS broth or white must). Specificity of LfcinB(17-31) for Lactobacillus brevis, Pediococcus damnosus, and O. oeni was demonstrated in must fermentation experiments in which these three LAB co-existed with the winemaking Saccharomyces cerevisiae T73 in the presence of the peptide. Finally, fermentation experiments also showed that LfcinB(17-31) at inhibitory concentrations did not alter either fermentation kinetics or specific enological parameters. PMID:19269579

Enrique, María; Manzanares, Paloma; Yuste, María; Martínez, Mireia; Vallés, Salvador; Marcos, Jose F

2008-12-10

373

Updating the importance of lactic acid bacteria in fish farming: natural occurrence and probiotic treatments.  

PubMed

Many recent papers have deepened the state of knowledge about lactic acid bacteria (LAB) in fish gut. In spite of high variability in fish microbiota, LAB are sometimes abundant in the intestine, notably in freshwater fish. Several strains of Streptococcus are pathogenic to fish. Streptococcus iniae and Lactococcus garvieae are major fish pathogens, against which commercial vaccines are available. Fortunately, most LAB are harmless, and some strains have been reported for beneficial effects on fish health. A major step forward in recent years was the converging evidence that LAB can stimulate the immune system in fish. An open question is whether viability can affect immunostimulation. The issue is crucial to commercialize live probiotics rather than inactivated preparations or extracts. There has been a regain of interest in allochthonous strains used as probiotics for terrestrial animals or humans, due to economical and regulatory constraints, but the short survival in sea water may limit application to marine fish. If viability is required, alternative treatments may include the incorporation of prebiotics in feed, and other dietary manipulations that could promote intestinal LAB. Antagonism to pathogens is the other main feature of candidate probiotics, and there are many reports concerning mainly carnobacteria and Enterococcus. Some bacteriocins were characterized which may be of interest not only for aquaculture, but also for food preservation. PMID:17957117

Gatesoupe, François-Joël

2008-01-01

374

Esterase activity of lactic acid bacteria isolated from malolactic fermentation of red wines.  

PubMed

The goal of this study was to examine the esterase activity of 243 lactic acid bacteria (LAB) strains from wines of different red grape varieties, belonging to the genera Oenococcus, Lactobacillus, Pediococcus and Enterococcus. p-Nitrophenyl octanoate was used as substrate. All strains presented esterase activity in the first screening, but only those showing higher activity were used in subsequent studies to determine the cellular location of this activity, the influence of pH, temperature and the presence of ethanol and the substrate specificity. For the thirteen selected strains, the highest activity was observed in the intracellular fraction. Responses to pH, temperature and ethanol were strain-dependent, but for all the strains, a marked decrease in activity in presence of ethanol was observed. When the influence of pH and ethanol acting together was studied at 25 °C and 37 °C, temperature-dependent differences were not observed for any of the strains except for Oen6. In the substrate specificity assay, the majority of strains of all genera displayed a trend to more readily hydrolyse ester substrates from C8 and longer. PMID:23558198

Pérez-Martín, Fátima; Seseña, Susana; Izquierdo, Pedro Miguel; Palop, María Llanos

2013-03-14

375

Broad-spectrum antifungal-producing lactic acid bacteria and their application in fruit models.  

PubMed

A large-scale screen of some 7,000 presumptive lactic acid bacteria (LAB), isolated from animal, human, or plant origin, identified 1,149 isolates with inhibitory activity against the food-spoilage mould Penicillium expansum. In excess of 500 LAB isolates were subsequently identified to produce a broad spectrum of activity against P. expansum, Penicillium digitatum, Penicillium notatum, Penicillium roqueforti, Rhizopus stolonifer, Fusarium culmorum, Aspergillus fumigatus and Rhodotorula mucilaginosa. Partial 16S rRNA sequencing of 94 broad spectrum isolates revealed that the majority of antifungal producers were strains of Lactobacillus plantarum. The remaining population was composed of Weissella confusa and Pediococcus pentosaceous isolates. Characterization of six selected broad-spectrum antifungal LAB isolates revealed that antifungal activity is maximal at a temperature of 30 °C, a pH of 4.0 and is stable across a variety of salt concentrations. The antifungal compound(s) was shown to be neither proteinaceous nor volatile in nature. P. pentosaceous 54 was shown to have protective properties against P. expansum spoilage when applied in pear, plum and grape models, therefore representing an excellent candidate for food-related applications. PMID:23160868

Crowley, Sarah; Mahony, Jennifer; van Sinderen, Douwe

2012-11-17

376

Spoilage characteristics of traditionally packaged ground beef with added lactic acid bacteria displayed at abusive temperatures.  

PubMed

Growth of pathogenic organisms such as Escherichia coli O157:H7 and Salmonella spp. can be inhibited in ground beef through the addition of certain lactic acid-producing bacteria (LAB; Lactobacillus acidophilus NP51, Lactobacillus crispatus NP35, Pediococcus acidilactici, and Lactococcus lactis ssp. lactis). This study evaluated the effects of LAB inclusion on the organoleptic and biochemical properties typically associated with spoilage in traditionally packaged ground beef displayed at abusive (10°C) temperatures for 36 h. Trained and untrained panelist evaluations of lean color and off-odor, as well as instrumental color analyses, did not indicate an effect on spoilage traits due to LAB utilization (P > 0.05). However, display length affected each variable independently and was indicative of decreased stability and acceptability as display time (h) increased (P < 0.05). Thiobarbituric acid values were decreased for ground beef with added LAB (P < 0.05), but likely can be related to bacterial degradation of lipid oxidation by-products because no reduction in organoleptic traits due to oxidation was noted between treatments. Overall, LAB did not adversely influence the spoilage characteristics of traditionally packaged ground beef displayed at abusive temperatures for up to 36 h. Furthermore, biochemical and sensory indicators of spoilage were present for all treatments at the conclusion of display. Therefore, LAB can be added to ground beef in traditional packaging as a processing intervention without masking or delaying the expected spoilage characteristics. PMID:22064744

Hoyle Parks, A R; Brashears, M M; Woerner, W D; Martin, J N; Thompson, L D; Brooks, J C

2011-11-07

377

Natural populations of lactic acid bacteria in douchi from Yunnan Province, China*  

PubMed Central

This research was aimed at isolating and identifying the predominant lactic acid bacteria (LAB) in the traditional Chinese salt-fermented soybean food, douchi, from Yunnan, China. The predominant LAB present were isolated and identified by conventional culture-dependent methods combined with molecular biological methods. Two hundred and sixty isolates were obtained from thirty kinds of traditional fermented douchi from six cities and counties in Yunnan, and those strains were divided into twelve groups by their morphological and biochemical characteristics. Based on 16S ribosomal DNA (rDNA) sequencing and analysis, 56 representative strains were identified as belonging to 6 genera and 14 species: Lactobacillus (4 spp.), Weissella (3 spp.), Pediococcus (2 spp.), Staphylococcus (2 spp.), Enterococcus (1 sp.), and Bacillus (2 spp.). The results show that douchi contains a large natural population of LAB of diverse composition from which some strains could be selected as starters for functional fermented foods. This is the first study on the original douchi from Yunnan, and the results suggest that it may be a useful source for the isolation of LAB. This study has also laid a foundation for further research on developing functional douchi products.

Liu, Chen-jian; Gong, Fu-ming; Li, Xiao-ran; Li, Hai-yan; Zhang, Zhong-hua; Feng, Yue; Nagano, Hiroko

2012-01-01

378

Identification of lactic acid bacteria isolated from Tarhana, a traditional Turkish fermented food.  

PubMed

Tarhana is a traditional fermented product produced from a mixture of spontaneously fermented yogurt and wheat flour in Turkey. The aims of the present study were to enumerate and identify for the first time by molecular biology-based methods predominant lactic acid bacteria (LAB) isolated during processing of Tarhana. Samples were collected from eight different regions of Turkey. In order to explore the relationship between raw material and the microbiology of Tarhana, yogurt and wheat flour were also analyzed. A total of 226 Gram-positive and catalase-negative isolates were obtained from MRS, M17 and SBM (Slanetz and Bartley Medium). The isolates were grouped and identified using a combination of pheno- and genotypic methods including rep-PCR fingerprinting [(GTG)(5) primer], multiplex PCR, 16S rRNA gene sequencing and carbohydrate assimilation profiling. Pediococcus acidilactici were found to constitute 27% of the isolates, 19% were identified as Streptococcus thermophilus, 19% as Lactobacillus fermentum, 12% as Enterococcus faecium, 7% as Pediococcus pentosaceus, 5% as Leuconostoc pseudomesenteroides, 4% as Weissella cibaria, 2% as Lactobacillus plantarum, 2% as Lactobacillus delbrueckii spp. bulgaricus, 2% as Leuconostoc citreum, 1% as Lactobacillus paraplantarum and 0.5% as Lactobacillus casei. The different production sites investigated all had individual LAB profiles, but with P. acidilactici and S. thermophilus being isolated from the majority of samples. The main source of P. acidilactici and S. thermophilus was found to be the yogurt. PMID:19703719

Sengun, Ilkin Yucel; Nielsen, Dennis S; Karapinar, Mehmet; Jakobsen, Mogens

2009-08-04

379

Gassericin A: a circular bacteriocin produced by Lactic acid bacteria Lactobacillus gasseri.  

PubMed

During the recent years extensive efforts have been made to find out bacteriocins from lactic acid bacteria (LAB) active against various food spoilage and pathogenic bacteria, and superior stabilities against heat treatments and pH variations. Bacteriocins isolated from LAB have been grouped into four classes. Circular bacteriocins which were earlier grouped among the four groups of bacteriocins, have recently been proposed to be classified into a different class, making it class V bacteriocins. Circular bacteriocins are special molecules, whose precursors must be post translationally modified to join the N to C termini with a head-to-tail peptide bond. Cyclization appears to make them less susceptible to proteolytic cleavage, high temperature and pH, and, therefore, provides enhanced stability as compared to linear bacteriocins. The advantages of circularization are also reflected by the fact that a significant number of macrocyclic natural products have found pharmaceutical applications. Circular bacteriocins were unknown two decades ago, and even to date, only a few circular bacteriocins from a diverse group of Gram positive organisms have been reported. The first example of a circular bacteriocin was enterocin AS-48, produced by Enterococcus faecalis AS-48. Gassereccin A, produced by Lactobacillus gasseri LA39, Reutericin 6 produced by Lactobacillus reuteri LA6 and Circularin A, produced by Clostridium beijerinickii ATCC 25,752, are further examples of this group of antimicrobial peptides. In the present scenario, Gassericin A can be an important tool in the food preservation owing to its properties of high pH and temperature tolerance and the fact that it is produced by LAB L. gasseri, whose many strains are proven probiotic. PMID:23712477

Pandey, Neha; Malik, R K; Kaushik, J K; Singroha, Garima

2013-05-28

380

Structure-Function Relationships of Glucansucrase and Fructansucrase Enzymes from Lactic Acid Bacteria  

PubMed Central

Lactic acid bacteria (LAB) employ sucrase-type enzymes to convert sucrose into homopolysaccharides consisting of either glucosyl units (glucans) or fructosyl units (fructans). The enzymes involved are labeled glucansucrases (GS) and fructansucrases (FS), respectively. The available molecular, biochemical, and structural information on sucrase genes and enzymes from various LAB and their fructan and ?-glucan products is reviewed. The GS?and FS enzymes are both glycoside hydrolase enzymes that act on the same substrate (sucrose) and catalyze (retaining) transglycosylation reactions that result in polysaccharide formation, but they possess completely different protein structures. GS enzymes (family GH70) are large multidomain proteins that occur exclusively in LAB. Their catalytic domain displays clear secondary-structure similarity with ?-amylase enzymes (family GH13), with a predicted permuted (?/?)8 barrel structure for which detailed structural and mechanistic information is available. Emphasis now is on identification of residues and regions important for GS enzyme activity and product specificity (synthesis of ?-glucans differing in glycosidic linkage type, degree and type of branching, glucan molecular mass, and solubility). FS enzymes (family GH68) occur in both gram-negative and gram-positive bacteria and synthesize ?-fructan polymers with either ?-(2?6) (inulin) or ?-(2?1) (levan) glycosidic bonds. Recently, the first high-resolution three-dimensional structures have become available for FS (levansucrase) proteins, revealing a rare five-bladed ?-propeller structure with a deep, negatively charged central pocket. Although these structures have provided detailed mechanistic insights, the structural features in FS enzymes dictating the synthesis of either ?-(2?6) or ?-(2?1) linkages, degree and type of branching, and fructan molecular mass remain to be identified.

van Hijum, Sacha A. F. T.; Kralj, Slavko; Ozimek, Lukasz K.; Dijkhuizen, Lubbert; van Geel-Schutten, Ineke G. H.

2006-01-01

381

Antimicrobial activity of bacteriocin-producing lactic acid bacteria isolated from cheeses and yogurts.  

PubMed

The biopreservation of foods using bacteriocinogenic lactic acid bacteria (LAB) isolated directly from foods is an innovative approach. The objectives of this study were to isolate and identify bacteriocinogenic LAB from various cheeses and yogurts and evaluate their antimicrobial effects on selected spoilage and pathogenic microorganisms in vitro as well as on a food commodity.LAB were isolated using MRS and M17 media. The agar diffusion bioassay was used to screen for bacteriocin or bacteriocin-like substances (BLS) producing LAB using Lactobacillus sakei and Listeria innocua as indicator organisms. Out of 138 LAB isolates, 28 were found to inhibit these bacteria and were identified as strains of Enterococcus faecium, Streptococcus thermophilus, Lactobacillus casei and Lactobacillus sakei subsp. sakei using 16S rRNA gene sequencing. Eight isolates were tested for antimicrobial activity at 5°C and 20°C against L. innocua, Escherichia coli, Bacillus cereus, Pseudomonas fluorescens, Erwinia carotovora, and Leuconostoc mesenteroides subsp. mesenteroides using the agar diffusion bioassay, and also against Penicillium expansum, Botrytis cinerea and Monilinia frucitcola using the microdilution plate method. The effect of selected LAB strains on L. innocua inoculated onto fresh-cut onions was also investigated.Twenty percent of our isolates produced BLS inhibiting the growth of L. innocua and/or Lact. sakei. Organic acids and/or H2O2 produced by LAB and not the BLS had strong antimicrobial effects on all microorganisms tested with the exception of E. coli. Ent. faecium, Strep. thermophilus and Lact. casei effectively inhibited the growth of natural microflora and L. innocua inoculated onto fresh-cut onions. Bacteriocinogenic LAB present in cheeses and yogurts may have potential to be used as biopreservatives in foods. PMID:22963659

Yang, En; Fan, Lihua; Jiang, Yueming; Doucette, Craig; Fillmore, Sherry

2012-09-10

382

[Bioaugmentation for shortcut nitrification in SBR treating for sewage containing sea water by nitrification-aerobic denitrification bacteria].  

PubMed

The feasibility of heterotrophic nitrification-aerobic denitrification bacteria applied in shortcut nitrification system was studied. Four heterotrophic nitrification-aerobic denitrification strains mixed with halotolerant activated sludge was added into SBR in order to test their bioaugmentation ability for shortcut nitrification system, which was treating for sewage containing sea water, and the difference between bioaugmentation system and original system was compared. The results showed that the maximum accumulation of NO2(-) -N in bioaugmentation system was 34.92% lower than that in original system, and the time of maximum accumulation of NO2(-) -N was 2 hours earlier than that in original system. The TN and COD was continuously decreasing in the later phase of nitrification in bioaugmentation system, and finally the removal rate of TN and COD were 15.24% and 5.39% higher than that in original system respectively, as well as the removal rate of NH4(+) -N and the nitrosation rate were 6.85% and 14.47% higher than that in original system. And the pH was 0.46 higher than that in original system, whereas the ORP was 25.84 mV lower. It was considered that the function of heterotrophic nitrification-aerobic denitrification bacteria should strengthen the performance of bioaugmentation system. When the seawater content raised to 70%, the stability of bioaugmentation system was better than that in original system, and the current that transforming shortcut nitrification to complete nitrification was restrained by heterotrophic nitrification-aerobic denitrification bacteria effectively. The number of heterotrophic nitrification-aerobic denitrification bacteria was changed when bioaugmentation system and original system ran in different phase and the bacteria had a great loss with the discharge of activated sludge. These results may provide a theoretical reference about the feasibility that the heterotrophic nitrification-aerobic denitrification bacteria applied in shortcut nitrification system. PMID:21229749

Qu, Yang; Zhang, Pei-Yu; Yu, De-Shuang; Guo, Sha-Sha; Yang, Rui-Xia

2010-10-01

383

Exploitation of sweet cherry (Prunus avium L.) puree added of stem infusion through fermentation by selected autochthonous lactic acid bacteria.  

PubMed

Strains of Lactobacillus plantarum, Pediococcus acidilactici, Pediococcus pentosaceus and Leuconostoc mesenteroides subsp. mesenteroides were identified from 8 cultivars of sweet cherry by partial 16S rRNA gene sequence and subjected to typing by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analysis. Representative isolates from each species and each cultivar were screened based on the kinetics of growth on cherry puree added of (10%, v/v) stem infusion (CP-SI). A protocol for processing and storage of CP-SI, which included fermentation by selected autochthonous P. pentosaceus SWE5 and L. plantarum FP3 (started CP-SI) or spontaneous fermentation (unstarted CP-SI), was set up. Starters grew and remained viable at elevated cell numbers (ca. 9.0 log cfu g(-1)) during 60 days of storage at 4 °C. The number of presumptive lactic acid bacteria of the unstarted CP-SI did not exceed the value of ca. 3.0 log cfu g(-1). Consumption of carbohydrates (e.g., glucose and fructose) by starter lactic acid bacteria was limited as well as it was the lactic acid fermentation. Consumption of organic acids (e.g., malic acid) and free amino acids was evident, especially, throughout storage. Compared to CP-SI before processing, the concentrations of total phenolic compounds and anthocyanins did not vary in the started CP-SI. The concentration of anthocyanins slightly decreased in the unstarted CP-SI. The antioxidant activity, expressed as the scavenging activity toward DPPH radical, was found at highest level in the started CP-SI which approached that found in CP-SI before processing. During storage, viscosity and, especially, color indexes of started CP-SI were higher than those found in the unstarted CP-SI. Fermentation by autochthonous lactic acid bacteria seemed to also positively interfere with the sensory attributes of CP-SI. PMID:21569932

Di Cagno, Raffaella; Surico, Rosalinda Fortunata; Minervini, Giovanna; Rizzello, Carlo Giuseppe; Lovino, Raffaella; Servili, Maurizio; Taticchi, Agnese; Urbani, Sefania; Gobbetti, Marco

2010-12-31

384

Inhibition of the accumulation of uremic toxins in the blood and their precursors in the feces after oral administration of Lebenin, a lactic acid bacteria preparation, to uremic patients undergoing hemodialysis.  

PubMed

The plasma levels of phenol, p-cresol, and indican are markedly increased in uremic patients, and cannot be efficiently reduced by hemodialysis. Such uremic toxins, which are produced in the intestine as bacterial putrefactive metabolites, accumulate to a great degree in the feces of hemodialysis patients. Oral administration of Lebenin, a preparation consisting of antibiotic-resistant lactic acid bacteria, reduced the levels of fecal putrefactive metabolites to levels comparable with those of healthy subjects. Moreover, the plasma level of indican also significantly decreased in these Lebenin-treated patients. An analysis of the fecal microflora revealed that a disturbed composition of the microflora characterized by an overgrowth of aerobic bacteria is restored to normal by oral administration of Lebenin in hemodialysis patients. These results thus demonstrate that oral administration of lactic acid bacteria in uremic patients is effective in reducing the levels of uremic toxins, especially that of indican, in the blood by inhibiting bacterial production by means of correcting the intestinal microflora. PMID:8893154

Hida, M; Aiba, Y; Sawamura, S; Suzuki, N; Satoh, T; Koga, Y

1996-01-01

385

Genotypic characterization and safety assessment of lactic acid bacteria from indigenous African fermented food products  

PubMed Central

Background Indigenous fermented food products play an essential role in the diet of millions of Africans. Lactic acid bacteria (LAB) are among the predominant microbial species in African indigenous fermented food products and are used for different applications in the food and biotechnology industries. Numerous studies have described antimicrobial susceptibility profiles of LAB from different parts of the world. However, there is limited information on antimicrobial resistance profiles of LAB from Africa. The aim of this study was to characterize 33 LAB previously isolated from three different African indigenous fermented food products using (GTG)5-based rep-PCR, sequencing of the 16S rRNA gene and species-specific PCR techniques for differentiation of closely related species and further evaluate their antibiotic resistance profiles by the broth microdilution method and their haemolytic activity on sheep blood agar plates as indicators of safety traits among these bacteria. Results Using molecular biology based methods and selected phenotypic tests such as catalase reaction, CO2 production from glucose, colonies and cells morphology, the isolates were identified as Lactobacillus delbrueckii, Lactobacillus fermentum, Lactobacillus ghanensis, Lactobacillus plantarum, Lactobacillus salivarius, Leuconostoc pseudomesenteroides, Pediococcus acidilactici, Pediococcus pentosaceus and Weissella confusa. The bacteria were susceptible to ampicillin, chloramphenicol, clindamycin and erythromycin but resistant to vancomycin, kanamycin and streptomycin. Variable sensitivity profiles to tetracycline and gentamicin was observed among the isolates with Lb. plantarum, Lb. salivarius, W. confusa (except strain SK9-5) and Lb. fermentum strains being susceptible to tetracycline whereas Pediococcus strains and Lb. ghanensis strains were resistant. For gentamicin, Leuc. pseudomesenteroides, Lb. ghanensis and Ped. acidilactici strains were resistant to 64?mg/L whereas some W. confusa and Lb. plantarum strains had a MIC value of 16?mg/L and 32?mg/L respectively. No ?-haemolytic activity was observed, however, ?-haemolytic activity was observed in 27% (9) of the strains comprising Lb. salivarius (6), W. confusa (2) and Lb. delbrueckii (1) isolates. Conclusions The resistance to kanamycin and vancomycin is probably an intrinsic feature since similar observations were reported in the literature for LAB. Low prevalence of pathogenicity indicator traits were observed among the isolates especially with the presence of poor haemolytic activities and they could therefore be considered as interesting candidates for selection of starter cultures or probiotics for different applications.

2012-01-01

386

Suppression of growth of putrefactive and food poisoning bacteria by lactic acid fermentation of kitchen waste  

Microsoft Academic Search

In order to produce lactic acid, from kitchen waste, which is a raw material for biodegradable plastic production, it is necessary to store waste for some days in the system of kitchen waste collection and transportation through disposers and pipes. The changes of counts of viable cells in kitchen waste during storage were observed. In spite of seasonal variations, lactic

Q Wang; K Yamabe; J Narita; M Morishita; Y Ohsumi; K Kusano; Y Shirai; H. I Ogawa

2001-01-01

387

EVALUATION OF THE BIOSYS OPTICAL METHOD FOR RAPIDLY ENUMERATING POPULATIONS OF AEROBIC BACTERIA, COLIFORMS, AND ESCHERICHIA COLI FROM BROILER CHICKEN CARCASSES  

Microsoft Academic Search

SUMMARY A study was conducted to determine if a rapid optical method could be used to enumerate total aerobic bacteria, coliforms, and Escherichia coli from broiler chicken carcasses. The BioSys optical method was compared with standard methods for enumerating bacteria. For chicken carcasses, the correlation coefficients for the regression lines comparing aerobic plate counts, coliform counts, and E. coli most

S. M. RUSSELL

388

Analyses of spatial distributions of sulfate-reducing bacteria and their activity in aerobic wastewater biofilms  

SciTech Connect

The vertical distribution of sulfate-reducing bacteria (SRB) in aerobic wastewater biofilms grown on rotating disk reactors was investigated by fluorescent in situ hybridization (FISH) with 16S rRNA-targeted oligonucleotide probes. To correlate the vertical distribution of SRB populations with their activity, the microprofiles of O{sub 2}, H{sub 2}S, NO{sub 2}{minus}, NH{sub 2}{sup +}, and pH were measured with microelectrodes. In addition, a cross-evaluation of the FISH and microelectrode analyses was performed by comparing them with culture-based approaches and biogeochemical measurements. In situ hybridization revealed that a relatively high abundance of the probe SRB385-stained cells were evenly distributed throughout the biofilm, even in the toxic surface. The probe SRB660-stained Desulfobulbus spp. were found to be numerically important members of SRB populations. The result of microelectrode measurements showed that a high sulfate-reducing activity was found in a narrow anaerobic zone located about 150 to 300 {micro}m below the biofilm surface and above which an intensive sulfide oxidation zone was found. The biogeochemical measurements showed that elemental sulfur (S{degree}) was an important intermediate of the sulfide reoxidation in such thin wastewater biofilms, which accounted for about 75% of the total S pool in the biofilm. The contribution of an internal Fe-sulfur cycle to the overall sulfur cycle in aerobic wastewater biofilms was insignificant (less than 1%) due to the relatively high sulfate reduction rate.

Okabe, Satoshi; Itoh, Tsukasa; Satoh, Hisashi; Watanabe, Yoshimasa

1999-11-01

389

Diversity and phylogeny of the ectoine biosynthesis genes in aerobic, moderately halophilic methylotrophic bacteria.  

PubMed

The genes of ectoine biosynthesis pathway were identified in six species of aerobic, slightly halophilic bacteria utilizing methane, methanol or methylamine. Two types of ectoine gene cluster organization were revealed in the methylotrophs. The gene cluster ectABC coding for diaminobutyric acid (DABA) acetyltransferase (EctA), DABA aminotransferase (EctB) and ectoine synthase (EctC) was found in methanotrophs Methylobacter marinus 7C and Methylomicrobium kenyense AMO1(T). In methanotroph Methylomicrobium alcaliphilum ML1, methanol-utilizers Methylophaga thalassica 33146(T) , Methylophaga alcalica M8 and methylamine-utilizer Methylarcula marina h1(T), the genes forming the ectABC-ask operon are preceded by ectR, encoding a putative transcriptional regulatory protein EctR. Phylogenetic relationships of the Ect proteins do not correlate with phylogenetic affiliation of the strains, thus implying that the ability of methylotrophs to produce ectoine is most likely the result of a horizontal transfer event. PMID:21971967

Reshetnikov, Alexander S; Khmelenina, Valentina N; Mustakhimov, Ildar I; Kalyuzhnaya, Marina; Lidstrom, Mary; Trotsenko, Yuri A

2011-10-05

390

Effect of linear alkylbenzene sulfonates on the growth of aerobic heterotrophic cultivable bacteria isolated from an agricultural soil  

Microsoft Academic Search

An enrichment culture technique was used to isolate soil bacteria capable of growing in the presence of two different concentrations\\u000a of linear alkylbenzene sulfonates (LAS) (10 and 500 ?g ml?1). Nine bacterial strains, representatives of the major colony types of aerobic heterotrophic cultivable bacteria in the enriched\\u000a samples, were isolated and subsequently identified by PCR-amplification and partial sequencing of the 16S rRNA

María del Mar Sánchez-Peinado; Jesús González-López; Belén Rodelas; Vanesa Galera; Clementina Pozo; María Victoria Martínez-Toledo

2008-01-01

391

Exploring Diversity of Cultivable Aerobic Endospore-forming Bacteria: From Pasteurization to Procedures Without Heat-Shock Selection  

Microsoft Academic Search

\\u000a The assessment of the diversity of populations with low abundances in soil, as are most of the aerobic endospore-forming bacteria,\\u000a is a real challenge in modern studies of microbial ecology. Besides the culture-independent approaches reported in De Vos,\\u000a Studying the bacterial diversity of the soil by culture-independent approaches. In: Logan NA (ed) Endospore forming soil bacteria\\u000a (Soil Biology 27). Springer,

O. Berge; P. Mavingui; T. Heulin

392

Discrimination of Aerobic Endospore-forming Bacteria via Electrospray-Ionization Mass Spectrometry of Whole Cell Suspensions  

Microsoft Academic Search

Direct injection electrospray ionization mass spectrometry (ESI-MS) without prior analyte separation was investigated for the analysis of whole cell suspensions of bacteria. Thirty-six strains of aerobic endospore-forming bacteria, consisting of six Bacillus species and one Brevibacillus species, were studied. ESI was performed in the positive ion mode on the bacterial suspensions. Several peaks in the range of 250-1500 m\\/z were

Seetharaman Vaidyanathan; Jem J. Rowland; Douglas B. Kell; Royston Goodacre

2001-01-01

393

Impact of an Aerobic Thermophilic Sequencing Batch Reactor on Antibiotic-Resistant Anaerobic Bacteria in Swine Waste  

Microsoft Academic Search

The introduction of antibiotics to animal feed has contributed to the selection of antibiotic-resistant bacteria in concentrated\\u000a animal feeding operations. The aim of this work was to characterize the impact of an aerobic thermophilic biotreatment on\\u000a anaerobic antibiotic-resistant bacteria in swine waste. Despite 162- to 6,166-fold reduction in antibiotic-resistant populations\\u000a enumerated in the swine waste at 25°C and 37°C, resistant

Martin R. Chénier; Pierre Juteau

2009-01-01

394

Diversity in growth and protein degradation by dairy relevant lactic acid bacteria species in reconstituted whey.  

PubMed

The high nutritional value of whey makes it an interesting substrate for the development of fermented foods. The aim of this work was to evaluate the growth and proteolytic activity of sixty-four strains of lactic acid bacteria in whey to further formulate a starter culture for the development of fermented whey-based beverages. Fermentations were performed at 37 °C for 24 h in 10 and 16% (w/v) reconstituted whey powder. Cultivable populations, pH, and proteolytic activity (o-phthaldialdehyde test) were determined at 6 and 24 h incubation. Hydrolysis of whey proteins was analysed by Tricine SDS-PAGE. A principal component analysis (PCA) was applied to evaluate the behaviour of strains. Forty-six percent of the strains grew between 1 and 2 ?log CFU/ml while 19% grew less than 0·9 ?log CFU/ml in both reconstituted whey solutions. Regarding the proteolytic activity, most of the lactobacilli released amino acids and small peptides during the first 6 h incubation while streptococci consumed the amino acids initially present in whey to sustain growth. Whey proteins were degraded by the studied strains although to different extents. Special attention was paid to the main allergenic whey protein, ?-lactoglobulin, which was degraded the most by Lactobacillus acidophilus CRL 636 and Lb. delbrueckii subsp. bulgaricus CRL 656. The strain variability observed and the PCA applied in this study allowed selecting appropriate strains able to improve the nutritional characteristics (through amino group release and protein degradation) and storage (decrease in pH) of whey. PMID:22559062

Pescuma, Micaela; Hébert, Elvira M; Bru, Elena; Font de Valdez, Graciela; Mozzi, Fernanda

2012-05-01

395

Biodiversity of lactic acid bacteria and yeasts in spontaneously-fermented buckwheat and teff sourdoughs.  

PubMed

In this study, four different laboratory scale gluten-free (GF) sourdoughs were developed from buckwheat or teff flours. The fermentations were initiated by the spontaneous biota of the flours and developed under two technological conditions (A and B). Sourdoughs were propagated by continuous back-slopping until the stability was reached. The composition of the stable biota occurring in each sourdough was assessed using both culture-dependent and -independent techniques. Overall, a broad spectrum of lactic acid bacteria (LAB) and yeasts species, belonging mainly to the genera Lactobacillus, Pediococcus, Leuconostoc, Kazachstania and Candida, were identified in the stable sourdoughs. Buckwheat and teff sourdoughs were dominated mainly by obligate or facultative heterofermentative LAB, which are commonly associated with traditional wheat or rye sourdoughs. However, the spontaneous fermentation of the GF flours resulted also in the selection of species which are not consider endemic to traditional sourdoughs, i.e. Pediococcus pentosaceus, Leuconostoc holzapfelii, Lactobacillus gallinarum, Lactobacillus vaginalis, Lactobacillus sakei, Lactobacillus graminis and Weissella cibaria. In general, the composition of the stable biota was strongly affected by the fermentation conditions, whilst Lactobacillus plantarum dominated in all buckwheat sourdoughs. Lactobacillus pontis is described for the first time as dominant species in teff sourdough. Among yeasts, Saccharomyces cerevisiae and Candida glabrata dominated teff sourdoughs, whereas the solely Kazachstania barnetti was isolated in buckwheat sourdough developed under condition A. This study allowed the identification and isolation of LAB and yeasts species which are highly competitive during fermentation of buckwheat or teff flours. Representatives of these species can be selected as starters for the production of sourdough destined to GF bread production. PMID:21356457

Moroni, Alice V; Arendt, Elke K; Dal Bello, Fabio

2010-10-28

396

Detection, identification and characterization of bacteriocin-producing lactic acid bacteria from retail food products.  

PubMed

Forty bacteriocin-producing (Bac+) lactic acid bacteria (LAB) were isolated from food samples purchased from retail supermarkets and local farms. Of the 40 Bac+ isolates, 18 were isolated from 85 food samples by enrichment (21% isolation rate) whereas eight were obtained from 63 samples by direct plating (13% isolation rate). By direct plating, Bac+ LAB were detected at levels up to 2.4 x 10(5) cfu/g in ready-to-eat meats. The Bac+ isolates were identified by carbohydrate fermentation patterns, SDS-PAGE protein patterns, and other biochemical characteristics; SDS-PAGE proved invaluable in identifying strains that could not be identified by other means. Differential inhibitory spectra against indicator microorganisms assisted in the identification of 19 unique Bac+ isolates. Bac+ LAB included Enterococcus faecalis, Lactobacillus curvatus, Lb. delbrueckii, Lb. plantarum, Lactococcus lactis, and Pediococcus acidilactici. Lb. curvatus (four strains) and Lc. lactis (nine strains) were the only isolates inhibitory to foodborne pathogens including Listeria monocytogenes, Bacillus cereus, Clostridium perfringens and Staphylococcus aureus. Some Lc. lactis isolates inhibited as many as nine Gram-positive genera. Lb. curvatus FS47 and FS65 grew to high cell densities and produced bacteriocin at 6 degrees C; however, Lc. lactis FS56 produced greater levels of bacteriocin at lower cell densities. The high incidence of Bac+ LAB detected in retail foods indicates that the public is consuming a wide variety of Bac+ LAB that occur as natural contaminants. These data suggest a greater role for bacteriocins as biopreservatives in food. PMID:8257654

Garver, K I; Muriana, P M

1993-09-01

397

Regulation of the activity of lactate dehydrogenases from four lactic acid bacteria.  

PubMed

Despite high similarity in sequence and catalytic properties, the l-lactate dehydrogenases (LDHs) in lactic acid bacteria (LAB) display differences in their regulation that may arise from their adaptation to different habitats. We combined experimental and computational approaches to investigate the effects of fructose 1,6-bisphosphate (FBP), phosphate (Pi), and ionic strength (NaCl concentration) on six LDHs from four LABs studied at pH 6 and pH 7. We found that 1) the extent of activation by FBP (Kact) differs. Lactobacillus plantarum LDH is not regulated by FBP, but the other LDHs are activated with increasing sensitivity in the following order: Enterococcus faecalis LDH2 ? Lactococcus lactis LDH2 < E. faecalis LDH1 < L. lactis LDH1 ? Streptococcus pyogenes LDH. This trend reflects the electrostatic properties in the allosteric binding site of the LDH enzymes. 2) For L. plantarum, S. pyogenes, and E. faecalis, the effects of Pi are distinguishable from the effect of changing ionic strength by adding NaCl. 3) Addition of Pi inhibits E. faecalis LDH2, whereas in the absence of FBP, Pi is an activator of S. pyogenes LDH, E. faecalis LDH1, and L. lactis LDH1 and LDH2 at pH 6. These effects can be interpreted by considering the computed binding affinities of Pi to the catalytic and allosteric binding sites of the enzymes modeled in protonation states corresponding to pH 6 and pH 7. Overall, the results show a subtle interplay among the effects of Pi, FBP, and pH that results in different regulatory effects on the LDHs of different LABs. PMID:23720742

Feldman-Salit, Anna; Hering, Silvio; Messiha, Hanan L; Veith, Nadine; Cojocaru, Vlad; Sieg, Antje; Westerhoff, Hans V; Kreikemeyer, Bernd; Wade, Rebecca C; Fiedler, Tomas

2013-05-17

398

Distribution of antimicrobial-resistant lactic acid bacteria in natural cheese in Japan.  

PubMed

To determine and compare the extent of contamination caused by antimicrobial-resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P?=?0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm-made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32?µg/mL). Leuconostoc isolates from three Japanese farm-made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to?>?512?µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial-resistant LAB in imported and Japanese farm-made cheeses on the Japanese market, but not in Japanese commercial cheeses. PMID:23930694

Ishihara, Kanako; Nakajima, Kumiko; Kishimoto, Satoko; Atarashi, Fumiaki; Muramatsu, Yasukazu; Hotta, Akitoyo; Ishii, Satomi; Takeda, Yasuyuki; Kikuchi, Masanori; Tamura, Yutaka

2013-10-01

399

Lactic acid bacteria contribution to gut microbiota complexity: lights and shadows.  

PubMed

Lactic Acid Bacteria (LAB) are ancient organisms that cannot biosynthesize functional cytochromes, and cannot get ATP from respiration. Besides sugar fermentation, they evolved electrogenic decarboxylations and ATP-forming deiminations. The right balance between sugar fermentation and decarboxylation/deimination ensures buffered environments thus enabling LAB to survive in human gastric trait and colonize gut. A complex molecular cross-talk between LAB and host exists. LAB moonlight proteins are made in response to gut stimuli and promote bacterial adhesion to mucosa and stimulate immune cells. Similarly, when LAB are present, human enterocytes activate specific gene expression of specific genes only. Furthermore, LAB antagonistic relationships with other microorganisms constitute the basis for their anti-infective role. Histamine and tyramine are LAB bioactive catabolites that act on the CNS, causing hypertension and allergies. Nevertheless, some LAB biosynthesize both gamma-amino-butyrate (GABA), that has relaxing effect on gut smooth muscles, and beta-phenylethylamine, that controls satiety and mood. Since LAB have reduced amino acid biosynthetic abilities, they developed a sophisticated proteolytic system, that is also involved in antihypertensive and opiod peptide generation from milk proteins. Short-chain fatty acids are glycolytic and phosphoketolase end-products, regulating epithelial cell proliferation and differentiation. Nevertheless, they constitute a supplementary energy source for the host, causing weight gain. Human metabolism can also be affected by anabolic LAB products such as conjugated linoleic acids (CLA). Some CLA isomers reduce cancer cell viability and ameliorate insulin resistance, while others lower the HDL/LDL ratio and modify eicosanoid production, with detrimental health effects. A further appreciated LAB feature is the ability to fix selenium into seleno-cysteine. Thus, opening interesting perspectives for their utilization as antioxidant nutraceutical vectors. PMID:22919677

Pessione, Enrica

2012-06-22

400

Surface of Lactic Acid Bacteria: Relationships between Chemical Composition and Physicochemical Properties  

PubMed Central

The surface chemical composition and physicochemical properties (hydrophobicity and zeta potential) of two lactic acid bacteria, Lactococcus lactis subsp. lactis bv. diacetilactis and Lactobacillus helveticus, have been investigated using cells harvested in exponential or stationary growth phase. The surface composition determined by X-ray photoelectron spectroscopy (XPS) was converted into a molecular composition in terms of proteins, polysaccharides, and hydrocarbonlike compounds. The concentration of the last was always below 15% (wt/wt), which is related to the hydrophilic character revealed by water contact angles of less than 30°. The surfaces of L. lactis cells had a polysaccharide concentration about twice that of proteins. The S-layer of L. helveticus was either interrupted or crossed by polysaccharide-rich compounds; the concentration of the latter was higher in the stationary growth phase than in the exponential growth phase. Further progress was made in the interpretation of XPS data in terms of chemical functions by showing that the oxygen component at 531.2 eV contains a contribution of phosphate in addition to the main contribution of the peptide link. The isoelectric points were around 2 and 3, and the electrophoretic mobilities above pH 5 (ionic strength, 1 mM) were about ?3.0 × 10?8 and ?0.6 × 10?8 m2 s?1 V?1 for L. lactis and L. helveticus, respectively. The electrokinetic properties of the latter reveal the influence of carboxyl groups, while the difference between the two strains is related to a difference between N/P surface concentration ratios, reflecting the relative exposure of proteins and phosphate groups at the surface.

Boonaert, Christophe J. P.; Rouxhet, Paul G.

2000-01-01

401

Competitive inhibition of Listeria monocytogenes in ready-to-eat meat products by lactic acid bacteria.  

PubMed

Forty-nine strains of lactic acid bacteria (LAB), isolated from commercially available ready-to-eat (RTE) meat products, were screened for their ability to inhibit the growth of Listeria monocytogenes at refrigeration (5 degrees C) temperatures on agar spot tests. The three most inhibitory strains were identified as Pediococcus acidilactici, Lactobacillus casei, and Lactobacillus paracasei by 16S rDNA sequence analysis. Their antilisterial activity was quantified in associative cultures in deMan Rogosa Sharpe (MRS) broth at 5 degrees C for 28 days, resulting in a pathogen reduction of 3.5 log10 cycles compared to its initial level. A combined culture of these strains was added to frankfurters and cooked ham coinoculated with L. monocytogenes, vacuum packaged, and stored at 5 degrees C for 28 days. Bacteriostatic activity was observed in cooked ham, whereas bactericidal activity was observed in frankfurters. Numbers of L. monocytogenes were 4.2 to 4.7 log10 and 2.6 log10 cycles lower than controls in frankfurters and cooked ham, respectively, after the 28-day refrigerated storage. In all cases, numbers of LAB increased by only 1 log10 cycle. The strain identified as P. acidilactici was possibly a bacteriocin producer, whereas the antilisterial activity of the other two strains was due to the production of organic acids. There was no significant difference (P > 0.05) in the antilisterial activity detected in frankfurters whether the LAB strains were used individually or as combined cultures. Further studies over a 56-day period indicated no impact on the quality of the product. This method represents a potential antilisterial intervention in RTE meats, because it inhibited the growth of the pathogen at refrigeration temperatures without causing sensory changes. PMID:11848562

Amézquita, A; Brashears, M M

2002-02-01

402

Synthesis of ?-Aminobutyric Acid by Lactic Acid Bacteria Isolated from a Variety of Italian Cheeses?  

PubMed Central

The concentrations of ?-aminobutyric acid (GABA) in 22 Italian cheese varieties that differ in several technological traits markedly varied from 0.26 to 391 mg kg?1. Presumptive lactic acid bacteria were isolated from each cheese variety (total of 440 isolates) and screened for the capacity to synthesize GABA. Only 61 isolates showed this activity and were identified by partial sequencing of the 16S rRNA gene. Twelve species were found. Lactobacillus paracasei PF6, Lactobacillus delbrueckii subsp. bulgaricus PR1, Lactococcus lactis PU1, Lactobacillus plantarum C48, and Lactobacillus brevis PM17 were the best GABA-producing strains during fermentation of reconstituted skimmed milk. Except for L. plantarum C48, all these strains were isolated from cheeses with the highest concentrations of GABA. A core fragment of glutamate decarboxylase (GAD) DNA was isolated from L. paracasei PF6, L. delbrueckii subsp. bulgaricus PR1, L. lactis PU1, and L. plantarum C48 by using primers based on two highly conserved regions of GAD. A PCR product of ca. 540 bp was found for all the strains. The amino acid sequences deduced from nucleotide sequence analysis showed 98, 99, 90, and 85% identity to GadB of L. plantarum WCFS1 for L. paracasei PF6, L. delbrueckii subsp. bulgaricus PR1, L. lactis PU1, and L. plantarum C48, respectively. Except for L. lactis PU1, the three lactobacillus strains survived and synthesized GABA under simulated gastrointestinal conditions. The findings of this study provide a potential basis for exploiting selected cheese-related lactobacilli to develop health-promoting dairy products enriched in GABA.

Siragusa, S.; De Angelis, M.; Di Cagno, R.; Rizzello, C. G.; Coda, R.; Gobbetti, M.

2007-01-01

403

Potential beneficial properties of bacteriocin-producing lactic acid bacteria isolated from smoked salmon.  

PubMed

Aims:? To evaluate the probiotic properties of strains isolated from smoked salmon and previously identified as bacteriocin producers. Methods and Results:? Strains Lactobacillus curvatus ET06, ET30 and ET31, Lactobacillus fermentum ET35, Lactobacillus delbrueckii ET32, Pediococcus acidilactici ET34 and Enterococcus faecium ET05, ET12 and ET88 survived conditions simulating the gastrointestinal tract (GIT) and produced bacteriocins active against several strains of Listeria monocytogenes, but presented very low activity against other lactic acid bacteria (LAB). Cell-free supernatants containing bacteriocins, added to 3-h-old cultures of L. monocytogenes 603, suppressed growth over 12?h. Auto-aggregation was strain-specific, and values ranged from 7·2% for ET35 to 12·1% for ET05. Various degrees of co-aggregation with L. monocytogenes 603, Lactobacillus sakei ATCC 15521 and Enterococcus faecalis ATCC 19443 were observed. Adherence of the bacteriocinogenic strains to Caco-2 cells was within the range reported for Lactobacillus rhamnosus GG, a well-known probiotic. The highest levels of hydrophobicity were recorded for Lact. curvatus (61·9-64·6%), Lact. fermentum (78·9%), Lact. delbrueckii (43·7%) and Ped. acidilactici (51·3%), which are higher than the one recorded for Lact. rhamnosus GG (53·3%). These strains were highly sensitive to several antibiotics and affected by several drugs from different generic groups in a strain-dependent manner. Conclusions:? Smoked salmon is a rich source of probiotic LAB. All strains survived conditions simulating the GIT and produced bacteriocins active against various pathogens. Adherence to Caco-2 cells was within the range reported for Lact. rhamnosus GG, a well-known probiotic. In addition, the high hydrophobicity readings recorded define the strains as good probiotics. Significance and Impact of the Study:? Smoked salmon contains a number of different probiotic LAB and could be marketed as having a potential beneficial effect. PMID:21251174

Todorov, S D; Furtado, D N; Saad, S M I; Tome, E; Franco, B D G M

2011-01-20

404

Diversity of lactic acid bacteria from Hussuwa, a traditional African fermented sorghum food.  

PubMed

The diversity of lactic acid bacteria associated with Hussuwa fermentation, a Sudanese fermented sorghum food, was studied using a polyphasic taxonomical approach. Predominant strains could be well characterised based on a combination of phenotypic tests and genotypic methods such as ARDRA, rep-PCR and RAPD-PCR, as well as 16S rRNA gene sequencing of representative strains. Thus, the majority (128 of 220, 58.3%) of strains exhibited phenotypic properties typical of heterofermentative lactobacilli and of these, 100 strains were characterised more closely using the genotyping methods. The majority (97/100) strains could be characterised as Lactobacillus fermentum strains. Seventy-two of 220 strains (32.7%) showed phenotypic properties that are characteristic of pediococci. Of 41 selected strains investigated by genotyping techniques, 38 (92.7%) could be characterised as Pediococcus acidilactici strains, while three (7.3%) could be characterised as Pediococcus pentosaceus strains. The Hussuwa fermentation thus appears to be dominated by L. fermentum strains and P. acidilactici strains. For this reason, we selected representative and predominant strains as potential starter cultures for Hussuwa fermentation. These strains, L. fermentum strains BFE 2442 and BFE 2282 and P. acidilactici strain BFE 2300, were shown on the basis of RAPD-PCR fingerprinting to predominate in a model fermentation when used as starter cultures inoculated at 1 x 10(6) CFU/g and to lower the pH of the fermentation to below pH 4.0 within 48 h. These cultures should be studied for further development as starter preparations in pilot scale studies in actual field fermentations. PMID:20630317

Yousif, Nuha M K; Huch, Melanie; Schuster, Tobias; Cho, Gyu-Sung; Dirar, Hamid A; Holzapfel, Wilhelm H; Franz, Charles M A P

2010-03-27

405

Numerical Taxonomy of Aerobic, Gram-negative Bacteria associated with Oysters and Surrounding Seawater of the Mediterranean Coast  

Microsoft Academic Search

A numerical taxonomic study was performed on 245 strains of heterotrophic, aerobic, marine bacteria, plus 26 reference strains. The isolates were obtained from oysters and seawater sampled monthly over one year, by direct plating on Marine Agar. The strains were characterised by 93 morphological, biochemical, physiological and nutritional tests. Clustering yielded 46 phena at 0.60 S level (SJ coefficient). Some

Margarita Ortigosa; Esperanza Garay; María-Jesús Pujalte

1995-01-01

406

Comparison between rinse and crush-and-rub sampling for aerobic bacteria recovery from broiler hatching eggs after sanitization  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study compared surface and deep eggshell aerobic bacteria recovered by rinse and crush-and-rub sampling methods for commercial hatching eggs after treatment with sanitizers. Eggs were arranged into 5 treatments consisting of No-treatment, Water, and three sanitizers. Sanitizers were Hydrogen ...

407

Comparison between Rinse and Crush-and-Rub Sampling for Aerobic Bacteria Recovery from Hatching Eggs after Sanitization  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study compared surface and deep eggshell aerobic bacteria recovered by rinse and crush-and-rub sampling methods for commercial hatching eggs after treatments with sanitizers. Eggs were arranged into 5 treatments consisting of three sanitizers, Water, and No-treatment. Sanitizers were Hydrogen...

408

Amino acid profiles of lactic acid bacteria, isolated from kefir grains and kefir starter made from them.  

PubMed

The characteristics of cell growth, lactic acid production, amino acid release and consumption by single-strain cultures of lactic acid bacteria (isolated from kefir grains), and by a multiple-strain kefir starter prepared from them, were studied. The change in the levels of free amino acids was followed throughout the kefir process: single-strain kefir bacteria and the kefir starter (Lactococcus lactis C15-1%+Lactobacillus helveticus MP12-3%+(Streptococcus thermophilus T15+Lactobacillus bulgaricus HP1 = 1:1)-3%) were cultivated in pasteurized (92 degrees C for 20 min) cow's milk (3% fat content) at 28 degrees C for 5 h (the kefir starter reached pH 4.7) and subsequently grown at 20 degrees C for 16 h; storage was at 4 degrees C for 168 h. The strain L. helveticus MP12 was unrivaled with respect to free amino acid production (53.38 mg (100 g)(-1)) and cell growth (17.8 x 10(8) CFU ml(-1)); however, it manifested the lowest acidification activity. L. bulgaricus HP1 released approximately 3.7 times less amino acids, nearly 5 times lower cell growth, and produced about 1.2 times more lactic acid. S. thermophilus T15 demonstrated dramatically complex amino acid necessities for growth and metabolism. With L. lactis C15, the highest levels of growth and lactic acid synthesis were recorded (18.3 x 10(8) CFU ml(-1) and 7.8 g l(-1) lactic acid at the 21st hour), and as for free amino acid production, it approximated L. bulgaricus HP1 (17.03 mg (100 g)(-1) maximum concentration). In the L. lactis C15 culture, the amino acids were used more actively throughout the first exponential growth phase (by the 10th hour) than during the second growth phase. The unique properties of the L. helveticus MP12 strain to produce amino acids were employed to create a symbiotic bioconsortium kefir culture, which, under conditions of kefir formation, enhanced lactic acid production and shortened the time required to reach pH 4.7; intensified cell growth activity, resulting in a respective 90- and 60-fold increase in the concentration of lactobacilli and cocci in the mixed culture compared to individual cultures; and accumulated free amino acids in the final kefir with higher total concentrations (56.88 mg (100 g)(-1)) and an individual concentration of essential amino acids (1.5 times) greater than that of yogurt. PMID:16297479

Simova, Emilina; Simov, Zhelyasko; Beshkova, Dora; Frengova, Ginka; Dimitrov, Zhechko; Spasov, Zdravko

2005-11-16

409

Screening of a natural biodiversity of lactic and propionic acid bacteria for folate and vitamin B12 production in supplemented whey permeate  

Microsoft Academic Search

Lactic acid bacteria (LAB) and propionic acid bacteria (PAB) are known for the production of several important nutraceuticals. We screened 151 LAB and 100 PAB of different origins (fermented foods and feeds) for extracellular folate and intracellular vitamin B12 production in supplemented whey permeate using a standardized microbiological assay (folate) and HPLC (vitamin B12). Five LAB strains belonging to the

Selina Hugenschmidt; Susanne Miescher Schwenninger; Nicole Gnehm; Christophe Lacroix

2010-01-01

410

Cultivable microbiota of Lithobates catesbeianus and advances in the selection of lactic acid bacteria as biological control agents in raniculture.  

PubMed

The cultivable microbiota of skin and cloaca of captive Lithobates catesbeianus includes microorganisms generally accepted as beneficial and potentially pathogenic bacteria. In order to select a group of potentially probiotic bacteria, 136 isolates were evaluated for their surface properties and production of antagonistic metabolites. Then, 11 lactic acid bacteria (LAB) strains were selected and identified as Lactobacillus plantarum, Lb. brevis, Pediococcus pentosaceus, Lactococcus lactis, L. garvieae and Enterococcus gallinarum. Studies of compatibility indicate that all the strains could be included in a multi-strain probiotic, with the exception of Ent. gallinarum CRL 1826 which inhibited LAB species through a bacteriocin-like metabolite. These results contribute to the design of a probiotic product to improve the sanitary status of bullfrogs in intensive culture systems, to avoid the use of antibiotics and thus to reduce production costs. It could also be an alternative to prevent infectious diseases during the ex situ breeding of amphibian species under threat of extinction. PMID:22695175

Mendoza, Gabriela Montel; Pasteris, Sergio E; Ale, Cesar E; Otero, María C; Bühler, Marta I; Nader-Macías, María E Fátima

2012-06-12

411

The genetic diversity of lactic acid producing bacteria in the equine gastrointestinal tract  

Microsoft Academic Search

Seventy-two lactic acid producing bacterial isolates (excluding streptococci) were cultured from the gastrointestinal tract of six horses. Two of the horses were orally dosed with raftilose to induce lactic acidosis and laminitis while the remaining four were maintained on a roughage diet. Near complete 16S rDNA was amplified by PCR from the genomic DNA of each isolate. Following RFLP analysis

Rafat A. M. Al Jassim; Paul T. Scott; Andrea L. Trebbin; Darren Trott; Christopher C. Pollitt

2005-01-01

412

Lactic Acid Permeabilizes Gram-Negative Bacteria by Disrupting the Outer Membrane  

PubMed Central

The effect of lactic acid on the outer membrane permeability of Escherichia coli O157:H7, Pseudomonas aeruginosa, and Salmonella enterica serovar Typhimurium was studied utilizing a fluorescent-probe uptake assay and sensitization to bacteriolysis. For control purposes, similar assays were performed with EDTA (a permeabilizer acting by chelation) and with hydrochloric acid, the latter at pH values corresponding to those yielded by lactic acid, and also in the presence of KCN. Already 5 mM (pH 4.0) lactic acid caused prominent permeabilization in each species, the effect in the fluorescence assay being stronger than that of EDTA or HCl. Similar results were obtained in the presence of KCN, except for P. aeruginosa, for which an increase in the effect of HCl was observed in the presence of KCN. The permeabilization by lactic and hydrochloric acid was partly abolished by MgCl2. Lactic acid sensitized E. coli and serovar Typhimurium to the lytic action of sodium dodecyl sulfate (SDS) more efficiently than did HCl, whereas both acids sensitized P. aeruginosa to SDS and to Triton X-100. P. aeruginosa was effectively sensitized to lysozyme by lactic acid and by HCl. Considerable proportions of lipopolysaccharide were liberated from serovar Typhimurium by these acids; analysis of liberated material by electrophoresis and by fatty acid analysis showed that lactic acid was more active than EDTA or HCl in liberating lipopolysaccharide from the outer membrane. Thus, lactic acid, in addition to its antimicrobial property due to the lowering of the pH, also functions as a permeabilizer of the gram-negative bacterial outer membrane and may act as a potentiator of the effects of other antimicrobial substances.

Alakomi, H.-L.; Skytta, E.; Saarela, M.; Mattila-Sandholm, T.; Latva-Kala, K.; Helander, I. M.

2000-01-01

413

A PCR assay for detection of acetic acid-tolerant lactic acid bacteria in acidic food products.  

PubMed

A PCR assay for the detection of acetic acid-tolerant lactic acid bacteria in the genera of Lactobacillus and Pediococcus was developed in this study. Primers targeting the bacterial 16S rRNA gene were newly designed and used in this PCR assay. To determine the specificity of the assay, 56 different bacterial strains (of 33 genera), 2 fungi, 3 animals, and 4 plants were tested. Results were positive for most tested bacterial members of 16S rRNA gene-based phylogenetic groups (classified in the Lactobacillus casei and Pediococcus group), including Lactobacillus fructivorans, Lactobacillus brevis, Lactobacillus buchneri, Lactobacillus plantarum, and Lactobacillus paracasei. For all other bacterial strains and eukaryote tested, results were negative. Bacterial DNA for PCR was prepared with a simple procedure with the use of Chelex 100 resin from culture after growth in deMan Rogosa Sharpe broth (pH 6.0). To test this PCR assay for the monitoring of the acetic acid-tolerant lactic acid bacteria, L. fructivorans was inoculated into several acidic food as an indicator. Before the PCR, the inoculation of 10 to 50 CFU of bacteria per g of food was followed by a 28-h enrichment culture step, and the PCR assay allowed the detection of bacterial cells. Including the enrichment culture step, the entire PCR detection process can be completed within 30 h. PMID:15035383

Nakano, Shigeru; Matsumura, Atsushi; Yamada, Toshihiro

2004-03-01

414

Thermotolerant bacteriocin-producing lactic acid bacteria isolated from thai local fermented foods and their bacteriocin productivity.  

PubMed

Twenty-one samples of Thai local fermented foods were screened for thermotolerant bacteriocin-producing lactic acid bacteria. From 529 isolates of lactic acid bacteria, 121 isolates were able to inhibit the growth of certain bacterial strains. Of these 121 isolates, only 11 produced antibacterial agents that were capable of inhibiting the growth of multiple bacterial strains in a liquid medium. One strain (KKU 170) of these 11 isolates produced an antibacterial agent that could strongly inhibit the growth of selected strains of gram-positive bacteria including Listeria sp. The antibacterial agent produced by the strain KKU 170 was identified as a bacteriocin since it was inactivated by proteinase K treatment. The strain KKU 170 was identified as Pediococcus acidilactici by both biochemical tests and molecular biological techniques. Optimal production of bacteriocin by the strain KKU 170 was found in culture medium containing 0.2% glucose, at an initial culture pH of 6.5, and temperature of 45 ºC. The maximum bacteriocin activity (1600 AU ml(-1)) was reached at the late exponential phase of growth and displayed primary metabolite production. The partially purified bacteriocin of the strain KKU 170 was tolerant to heat treatment at 121 ºC for 30 min. PMID:21467627

Leelavatcharamas, Vichai; Arbsuwan, Nida; Apiraksakorn, Jirawan; Laopaiboon, Pattana; Kishida, Masao

2011-03-01

415

Isolation, identification, and selection of lactic acid bacteria from alfalfa sprouts for competitive inhibition of foodborne pathogens.  

PubMed

Several studies have investigated the control of pathogens on alfalfa sprouts, and some treatments have been shown to be effective in reducing pathogen populations. However, control methods investigated thus far only provide pathogen control at a given point in the sprouting process and can affect germination. Competitive inhibition of pathogens with lactic acid bacteria might provide pathogen control throughout the sprouting process and up to consumption. The purpose of this study was to isolate and identify lactic acid bacteria from alfalfa sprouts to inhibit the growth of foodborne pathogens. Fifty-eight lactic acid bacteria isolates were obtained from alfalfa seeds and sprouts. These isolates were evaluated for inhibitory action against Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes by agar spot tests. All pathogens were inhibited by 32 (55%) of the isolates, S. enterica by 56 (97%), E. coli O157:H7 by 49 (84%), and L. monocytogenes by 41 (71%). The isolates were identified by the Analytical Profile Index evaluation of carbohydrate utilization. Isolates obtained from a sample of alfalfa seeds and identified as Lactococcus lactis subsp. lactis showed zones of inhibition of 4.0 mm or greater for all pathogens. One of these isolates, Lactococcus lactis subsp. lactis (L7), and an isolate previously obtained, Pediococcus acidilactici (D3), were evaluated for competitive inhibition of S. enterica, E. coli O157:H7, and L. monocytogenes in deMan Rogosa Sharpe agar and broth. Pathogen populations were significantly reduced by day 5. The selected isolates will be further evaluated in future studies for inhibitory action toward S. enterica, E. coli O157:H7, and L. monocytogenes during sprouting. PMID:15151232

Wilderdyke, M R; Smith, D A; Brashears, M M

2004-05-01

416

Probiotic potential of lactic acid bacteria isolated from fermented dairy milks on antiproliferation of colon cancer cells  

Microsoft Academic Search

Fifty-four strains of lactic acid bacteria obtained from fermented dairy milks were investigated for possible use as probiotics\\u000a and for colon cancer biological products. Five of these strains inhibited growth of eight food-borne pathogens including Helicobacter pylori, Escherichia coli, and Salmonella typhimurium. Three of these strains survived at pH 2.5 and in 0.3% bile salts. Additionally they produced no haemolysis, were resistant\\u000a to

Mongkol Thirabunyanon; Pongphun Boonprasom; Piyanuch Niamsup

2009-01-01

417

Plutonium Oxidation State Distribution under Aerobic and Anaerobic Subsurface Conditions for Metal-Reducing Bacteria  

NASA Astrophysics Data System (ADS)

The fate and potential mobility of plutonium in the subsurface is receiving increased attention as the DOE looks to cleanup the many legacy nuclear waste sites and associated subsurface contamination. Plutonium is the near-surface contaminant of concern at several DOE sites and continues to be the contaminant of concern for the permanent disposal of nuclear waste. The mobility of plutonium is highly dependent on its redox distribution at its contamination source and along its potential migration pathways. This redox distribution is often controlled, especially in the near-surface where organic/inorganic contaminants often coexist, by the direct and indirect effects of microbial activity. The redox distribution of plutonium in the presence of facultative metal reducing bacteria (specifically Shewanella and Geobacter species) was established in a concurrent experimental and modeling study under aerobic and anaerobic conditions. Pu(VI), although relatively soluble under oxidizing conditions at near-neutral pH, does not persist under a wide range of the oxic and anoxic conditions investigated in microbiologically active systems. Pu(V) complexes, which exhibit high chemical toxicity towards microorganisms, are relatively stable under oxic conditions but are reduced by metal reducing bacteria under anaerobic conditions. These facultative metal-reducing bacteria led to the rapid reduction of higher valent plutonium to form Pu(III/IV) species depending on nature of the starting plutonium species and chelating agents present in solution. Redox cycling of these lower oxidation states is likely a critical step in the formation of pseudo colloids that may lead to long-range subsurface transport. The CCBATCH biogeochemical model is used to explain the redox mechanisms and final speciation of the plutonium oxidation state distributions observed. These results for microbiologically active systems are interpreted in the context of their importance in defining the overall migration of plutonium in the subsurface.

Reed, D. T.; Swanson, J.; Khaing, H.; Deo, R.; Rittmann, B.

2009-12-01

418

Growth and Metabolism of Lactic Acid Bacteria during and after Malolactic Fermentation of Wines at Different pH  

PubMed Central

Commercially produced red wines were adjusted to pH 3.0, 3.2, 3.5, 3.7, or 4.0 and examined during and after malolactic fermentation for growth of lactic acid bacteria and changes in the concentrations of carbohydrates, organic acids, amino acids, and acetaldehyde. With one exception, Leuconostoc oenos conducted the malolactic fermentation in all wines and was the only species to occur in wines at pH below 3.5. Malolactic fermentation by L. oenos was accompanied by degradation of malic, citric, and fumaric acids and production of lactic and acetic acids. The concentrations of arginine, histidine, and acetaldehyde also decreased at this stage, but the behavior of hexose and pentose sugars was complicated by other factors. Pediococcus parvulus conducted the malolactic fermentation in one wine containing 72 mg of total sulfur dioxide per liter. Fumaric and citric acids were not degraded during this malolactic fermentation, but hexose sugars were metabolized. P. parvulus and species of Lactobacillus grew after malolactic fermentation in wines with pH adjusted above 3.5. This growth was accompanied by the utilization of wine sugars and production of lactic and acetic acids.

Davis, C. R.; Wibowo, D. J.; Lee, T. H.; Fleet, G. H.

1986-01-01

419

Fermentation quality and chemical composition of shrub silage treated with lactic acid bacteria inoculants and cellulase additives.  

PubMed

Effects of lactic acid bacteria (LAB) inoculants and cellulase additives on fermentation quality and chemical compositions of shrub silages were studied by using a small-scale fermentation system. Two LAB inoculants of Qingbao (Lactobacillus plantarum, Pediococcus acidilacticii, Lactobacillus casei and Clostridium phage) and Caihe (Lactobacillus plantarum, Lactobacillus brevis and Pediococcus acidilactici) and a commercial cellulase made from Trichoderma reesei were used as additives for intermediate pea-shrub, rush bushclover, arborescent ceratoides and shrubby silage preparation. The crude protein, neutral detergent fiber and water-soluble carbohydrate contents of the four shrub materials were 10.1-14.2, 62.6-67.2 and 1.9-3.5% on a dry matter basis, respectively. All shrub silages had pH 3.40-4.43, ammonia-N 0.1-0.2% g/kg and lactic acid 1.3-2.9% on a fresh matter basis. The silage quality of LAB-inoculated silages did not have a greater effect than control silages, except shrubby silage preparation. Silages treated with the cellulase, the pH of rush bushclover and shrubby sweetvetch silage were significantly (P < 0.05) lower and the lactic acid content were significantly (P < 0.05) higher than the control silages. The results confirmed that shrub contained a relatively high content of crude protein; its silages can be preserved in good quality, and they are new potential resources for livestock feed. PMID:22515690

Sun, Qizhong; Gao, Fengqin; Yu, Zhu; Tao, Ya; Zhao, Shufen; Cai, Yimin

2011-10-18

420

Prevalent lactic acid bacteria in cider cellars and efficiency of Oenococcus oeni strains.  

PubMed

Malolactic fermentation (MLF) is an important step in cider production in order to allowing for improvement of microbiological stability and organoleptic characteristics of cider. Induction of this fermentation by using starter cultures enables a better control over this bioprocess, but although it is a common practice in winemaking, starters specifically focussed for cider MLF are not yet commercially available. Proper starter cultures need to present the ability to degrade l-malic acid conferring pleasing sensory characteristics while avoiding toxicological risks. In this work, lactic acid bacteria (LAB) were first isolated from MLF industrial cider samples, obtained in a cellar in the main cider-producing region of Spain, Asturias. Isolates, identified by molecular tools, belonged to the Lactobacillus brevis and Oenococcus oeni species. After a phylogenetic analysis, representative strains of both identified species were evaluated in order to determine their fermentation capacity, showing O. oeni the best behaviour in this cider fermentation, as previously demonstrated for wine in the literature. Consequently, and with the aim to test the influence at strain level, selection of O. oeni isolates as starters for cider fermentation has been undergone. In order to check the influence of geography over biodiversity, O. oeni strains from six different industrial cellars representing the distinct producing areas in the region (located in a ratio of 30 km) were analyzed by using a specific RAPD method. In this way, isolates were typed in five distinct groups, mainly corresponding to each producing area. All strains isolated from the same cellar showed the same RAPD profile revealing the significance of geographical origin in the indigenous cider LAB. Molecular tools were applied to reject those isolates exhibiting presence of genes related to organoleptic spoilage (exopolysaccharides and acrolein production) or food safety (biogenic amine production), as key selection criteria. Representative strains of each of the five O. oeni RAPD groups were tested as pure cultures to evaluate their technological utility for cider production. Experimental data of malic acid degradation and cell concentration obtained were fitted to previously selected kinetic models aimed to optimization and prediction of bioprocess performance. Four strains revealed as suitable potential starter cultures for conducting MLF in cider production. PMID:22850371

Sánchez, Ainoa; Coton, Monika; Coton, Emmanuel; Herrero, Mónica; García, Luis A; Díaz, Mario

2012-03-05

421

An analysis of the effectiveness of heat-killed lactic acid bacteria in alleviating allergic diseases.  

PubMed

Allergic diseases are reported to be caused by a skew in the balance between T helper type 1 and 2 cells. Because some lactic acid bacteria have been shown to stimulate IL-12 (p70) production, which in turn shifts the balance between the T helper type 1 and 2 cell response from the latter to the former, they have the potential to either prevent or ameliorate disease conditions or both. They have therefore been extensively studied in the recent past for their probiotic activities. Nevertheless, much less information is available concerning the microbial factors that determine the strain-dependent ability to affect the production of cytokines. The objectives of our study were first to select potentially probiotic lactobacilli that strongly stimulate cytokine production in vitro, and then to determine whether the selected Lactobacillus strains could suppress antigen-specific IgE production in vivo by using allergic model animals. Finally, our investigation was extended to analyze which bacterial components were responsible for the observed biological activity. Twenty strains of heat-killed lactobacilli isolated from humans were screened for their stimulatory activity for the production of IL-12 (p70) by murine splenocytes in vitro. The results showed that some strains of Lactobacillus plantarum and Lactobacillus gasseri had a higher stimulatory activity for IL-12 (p70) production than the other lactobacilli tested; however, this effect was strain dependent rather than species dependent. Oral administration of the heat-killed strains that showed higher stimulatory activity for IL-12 (p70) production tended to reduce the serum antigen-specific IgE levels in ovalbumin-sensitized BALB/c mice compared with the controls. Among the lactobacilli tested, L. gasseri OLL2809 showed the highest activity in reducing the level of antigen-specific IgE. Furthermore, the stimulatory activity for IL-12 (p70) production was found to be reduced after treating the lactobacilli with N-acetyl-muramidase and to be positively correlated with the amount of peptidoglycan in the cells. The present data suggest that L. gasseri OLL2809 is a good candidate for potential probiotics in terms of either the prevention or amelioration of allergic diseases or both. In addition, the strain-dependent stimulatory activity for IL-12 (p70) production was found to be due, at least in part, to the amount of peptidoglycan present in the cells. PMID:16840600

Sashihara, T; Sueki, N; Ikegami, S

2006-08-01

422

Potential of lactic acid bacteria isolated from specific natural niches in food production and preservation.  

PubMed

Autochthonous strains of lactic acid bacteria (LAB) have been isolated from traditionally homemade cheeses collected from specific ecological localities across Serbia and Montenegro. Genetic and biochemical analysis of this LAB revealed that they produce bacteriocins, proteinases and exopolysaccharides. LAB produces a variety of antimicrobial substances with potential importance for food fermentation and preservation. Apart from the metabolic end products, some strains also secrete antimicrobial substances known as bacteriocins. Among the natural isolates of LAB from homemade cheeses, bacteriocin producers were found in both lactococci and lactobacilli. Lactococcus lactis subsp. lactis BGMN1-5 was found to produce three narrow spectrum class II heat-stable bacteriocins. In addition to bacteriocin production, BGMN1-5 synthesized a cell envelope-associated proteinase (CEP) and shows an aggregation phenotype. Another isolate, L. lactis subsp. lactis BGSM1-19 produces low molecular mass (7 kDa) bacteriocin SM19 that showed antimicrobial activity against Staphylococcus aureus, Micrococcus flavus and partially against Salmonella paratyphi. Production of bacteriocin reaches a plateau after 8 h of BGSM1-19 growth. Bacteriocin SM19 retained activity within the wide pH range from 1 to 12 and after the treatment at 100 degrees C for 15 min. Among collection of lactobacilli, the isolate Lactobacillus paracasei subsp. paracasei BGSJ2-8 produces heat-stable bacteriocin SJ (approx. 5 kDa) polypeptide. It retained activity after treatment for 1 h at 100 degrees C, and in the pH range from 2 to 11. In addition to isolates from cheeses, bacteriocin-producing human oral lactobacilli were detected. Most of them showed antimicrobial activity against streptococci, staphylococci and micrococci, but not against Candida. Isolate BGHO1 that showed the highest antimicrobial activity was determined as L. paracasei. Interestingly, Lactobacillus helveticus BGRA43, which was isolated from the human intestine showed strong activity against Clostridium sporogenes, but it was not possible to detect any bacteriocin production in this isolate by using standard procedures. Further analysis of antimicrobial activity revealed that BGRA43 has a relatively broad spectrum. Lactobacilli resistant to nisin were also detected among natural isolates. They produce bacteriocins, which have no activity against nisin producing lactococci. PMID:16764959

Topisirovic, Ljubisa; Kojic, Milan; Fira, Djordje; Golic, Natasa; Strahinic, Ivana; Lozo, Jelena

2006-06-09

423

Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria  

NASA Astrophysics Data System (ADS)

Manned Mars exploration, especially for extended periods of time, will require recycle of materials to support human life. Here, a conceptual design is developed for a Martian agricultural system driven by biologically regenerative functions. One of the core biotechnologies function is the use of hyper-thermophilic aerobic composting bacterial ecology. These thermophilic bacteria can play an important role in increasing the effectiveness of the processing of human metabolic waste and inedible biomass and of converting them to fertilizer for the cultivation of plants. This microbial technology has been already well established for the purpose of processing sewage and waste materials for small local communities in Japan. One of the characteristics of the technology is that the metabolic heat release that occurs during bacterial fermentation raises the processing temperature sufficiently high at 80 100 °C to support hyper-thermophilic bacteria. Such a hyper-thermophilic system is found to have great capability of decomposing wastes including even their normally recalcitrant components, in a reasonably short period of time and of providing a better quality of fertilizer as an end-product. High quality compost has been shown to be a key element in creating a healthy regenerative food production system. In ground-based studies, the soil microbial ecology after the addition of high quality compost was shown to improve plant growth and promote a healthy symbiosis of arbuscular mycorrhizal fungi. Another advantage of such high processing temperature is the ability to sterilize the pathogenic organisms through the fermentation process and thus to secure the hygienic safety of the system. Plant cultivation is one of the other major systems. It should fully utilize solar energy received on the Martian surface for supplying energy for photosynthesis. Subsurface water and atmospheric carbon dioxide mined on Mars should be also used in the plant cultivation system. Oxygen and food production for human thus rely on local Martian resources. A tree growing subsystem will also give an interesting feature to Martian agriculture. In addition to producing excess oxygen, trees’ rigid body will provide structural material, which can be used for habitat construction. The combination of hyper-thermophilic aerobic composting, plant cultivation, and tree growing with utilizing in-situ natural local resources available on Mars can provide important elements which can enable space agriculture on Mars.

Space Agriculture Task Force; Ishikawa, Y.; Tomita-Yokotani, K.; Hashimoto, H.; Kitaya, Y.; Yamashita, M.; Nagatomo, M.; Oshima, T.; Wada, H.

424

Survival rate analysis of freeze-dried lactic acid bacteria using the arrhenius and z-value models.  

PubMed

The survival rate of five freeze-dried bacteria species, Lactobacillus plantarum, Lactobacillus pentosus, Weisella paramesenteroides, Leuconostoc mesenteroides, and Lactobacillus fermentum, was described in terms of reaction rate constants (D or k) and temperature sensitivity of rate constants (z or Ea). The freeze-dried strains were stored under vacuum at 55, 37, and 4 degrees C for 168 h, 17 days, and 2 months, respectively. D-values decreased and k increased with an increase of the storage temperature. Neither the z-value nor the inactivation energy (Ea) of the reaction was significantly different (P > 0.05) for all the strains, suggesting that thermal inactivation of the freeze-dried lactic acid bacteria may occur by the same mechanism. Therefore, it was possible to compare rate constants of survival for the freeze-dried strains studied. PMID:18326201

Yao, A A; Bera, F; Franz, C; Holzapfel, W; Thonart, P

2008-02-01

425

Production of Wax Esters during Aerobic Growth of Marine Bacteria on Isoprenoid Compounds  

PubMed Central

This paper describes the production of isoprenoid wax esters during the aerobic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four bacteria (Acinetobacter sp. strain PHY9, Pseudomonas nautica [IP85/617], Marinobacter sp. strain CAB [DSMZ 11874], and Marinobacter hydrocarbonoclasticus [ATCC 49840]) isolated from the marine environment. Different pathways are proposed to explain the formation of these compounds. In the case of 6,10,14-trimethylpentadecan-2-one, these esters result from the condensation of some acidic and alcoholic metabolites produced during the biodegradation, while phytol constitutes the alcohol moiety of most of the esters produced during growth on this isoprenoid alcohol. The amount of these esters formed increased considerably in N-limited cultures, in which the ammonium concentration corresponds to conditions often found in marine sediments. This suggests that the bacterial formation of isoprenoid wax esters might be favored in such environments. Although conflicting evidence exists regarding the stability of these esters in sediments, it seems likely that, under some conditions, bacterial esterification can enhance the preservation potential of labile compounds such as phytol.

Rontani, Jean-Francois; Bonin, Patricia C.; Volkman, John K.

1999-01-01

426

Numerical taxonomy of psychrotrophic lactic acid bacteria from prepacked meat and meat products  

Microsoft Academic Search

Ninety-four strains of lactic acid bateria isolated from refrigerated, prepacked meat and meat products were together with 59 reference strains of Brochothrix, Lactobacillus, Leuconostoc, Pediococcus and Streptococcus phenotypically classfied, using 96 unit characters. Data were examined using Simple Matching (SSM) or Jaccard coefficient (SJ), and unweighted pair group algorithm with arithmetic averages. Twenty-three clusters with two or more members were

Elisabeth Borch; Göran Molin

1988-01-01

427

THE SURVIVAL OF SILAGE INOCULANT LACTIC ACID BACTERIA IN RUMEN FLUID  

Technology Transfer Automated Retrieval System (TEKTRAN)

Twelve commercial silage inoculants were added at 1 and 10 million CFU/ml to clarified and strained rumen fluid taken from dairy cows, respectively, with and without 5 g/l glucose. The vials of inoculated rumen fluid was incubated anaerobically at 39 C. Changes in pH, lactic acid bacterial numbers a...

428

Effects of Inoculants Containing Propionic Acid Bacteria on Fermentation and Aerobic Stability of Corn Silage[1] and [2  

Microsoft Academic Search

The effects of microbial inoculants containing propionic acid bacteria on fermentation and aerobic stability of corn silage were examined. Whole-plant corn was ensiled for 3, 21, and 90 d in 5- to 7-kg capacity polyethylene bags, and six treatments were compared: no additive, Pediococcus cerevisiae at 3 × 105 cfu\\/g of fresh forage plus Lactobacillus planta- rum at 1.5 ×

G. E. Higginbotham; S. C. Mueller; K. K. Bolsen; E. J. DePeters

1998-01-01

429

Detection and Quantification of Bacteria Involved in Aerobic and Anaerobic Ammonium Oxidation in an Ammonium-Contaminated Aquifer  

Microsoft Academic Search

The aerobic and anaerobic ammonium-oxidizing bacterial guilds were studied from two multilevel samplers in an ammonium-contaminated aquifer in the UK. By end point polymerase chain reaction (PCR), the presence of betaproteobacterial ammonium-oxidizing bacteria and anaerobic ammonium-oxidizing (anammox) planctomycetes was demonstrated. The sequences of cloned anammox-specific PCR fragments had close relationships with known anammox strains. Real-time PCR was subsequently used to

Theo H. M. Smits; Arne Hüttmann; David N. Lerner; Christof Holliger

2009-01-01

430

Characterization of aerobic spore-forming bacteria associated with industrial dairy processing environments and product spoilage.  

PubMed

Due to changes in the design of industrial food processing and increasing international trade, highly thermoresistant spore-forming bacteria are an emerging problem in food production. Minimally processed foods and products with extended shelf life, such as milk products, are at special risk for contamination and subsequent product damages, but information about origin and food quality related properties of highly heat-resistant spore-formers is still limited. Therefore, the aim of this study was to determine the biodiversity, heat resistance, and food quality and safety affecting characteristics of aerobic spore-formers in the dairy sector. Thus, a comprehensive panel of strains (n=467), which originated from dairy processing environments, raw materials and processed foods, was compiled. The set included isolates associated with recent food spoilage cases and product damages as well as isolates not linked to product spoilage. Identification of the isolates by means of Fourier-transform infrared spectroscopy and molecular methods revealed a large biodiversity of spore-formers, especially among the spoilage associated isolates. These could be assigned to 43 species, representing 11 genera, with Bacillus cereus s.l. and Bacillus licheniformis being predominant. A screening for isolates forming thermoresistant spores (TRS, surviving 100°C, 20min) showed that about one third of the tested spore-formers was heat-resistant, with Bacillus subtilis and Geobacillus stearothermophilus being the prevalent species. Strains producing highly thermoresistant spores (HTRS, surviving 125°C, 30min) were found among mesophilic as well as among thermophilic species. B. subtilis and Bacillus amyloliquefaciens were dominating the group of mesophilic HTRS, while Bacillus smithii and Geobacillus pallidus were dominating the group of thermophilic HTRS. Analysis of spoilage-related enzymes of the TRS isolates showed that mesophilic strains, belonging to the B. subtilis and B. cereus groups, were strongly proteolytic, whereas thermophilic strains displayed generally a low enzymatic activity and thus spoilage potential. Cytotoxicity was only detected in B. cereus, suggesting that the risk of food poisoning by aerobic, thermoresistant spore-formers outside of the B. cereus group is rather low. PMID:23973839

Lücking, Genia; Stoeckel, Marina; Atamer, Zeynep; Hinrichs, Jörg; Ehling-Schulz, Monika

2013-07-16

431

Characterisation and biochemical properties of predominant lactic acid bacteria from fermenting cassava for selection as starter cultures.  

PubMed

A total of 375 lactic acid bacteria were isolated from fermenting cassava in South Africa, Benin, Kenya and Germany, and were characterised by phenotypic and genotypic tests. These could be divided into five main groups comprising strains of facultatively heterofermentative rods, obligately heterofermentative rods, heterofermentative cocci, homofermentative cocci and obligately homofermentative rods, in decreasing order of predominance. Most of the facultatively heterofermentative rods were identified by phenotypic tests as presumptive Lactobacillus plantarum-group strains, which also comprised the most predominant bacteria (54.4% of strains) isolated in the study. The next predominant group of lactic acid bacteria (14.1% of total isolates) consisted of obligately heterofermentative rods belonging either to the genus Lactobacillus or Weissella, followed by the heterofermentative cocci (13.9% of isolates) belonging to the genera Weissella or Leuconostoc. Homofermentative cocci were also isolated (13.3% of isolates). Biochemical properties such as production of alpha-amylase, beta-glucosidase, tannase, antimicrobials (presumptive bacteriocin and H(2)O(2)-production), acidification and fermentation of the indigestible sugars raffinose and stachyose, were evaluated in vitro for selection of potential starter strains. A total of 32 strains with one or more desirable biochemical properties were pre-selected and identified using rep-PCR fingerprinting in combination with 16S rRNA sequencing of representative rep-PCR cluster isolates. Of these strains, 18 were identified as L. plantarum, four as Lactobacillus pentosus, two each as Leuconostoc fallax, Weissella paramesenteroides and Lactobacillus fermentum, one each as Leuconostoc mesenteroides subsp. mesenteroides and Weissella cibaria, while two remained unidentified but could be assigned to the L. plantarum-group. These strains were further investigated for clonal relationships, using RAPD-PCR with three primers, and of the 32 a total of 16 strains were finally selected for the development as starter cultures for Gari production. PMID:17188771

Kostinek, M; Specht, I; Edward, V A; Pinto, C; Egounlety, M; Sossa, C; Mbugua, S; Dortu, C; Thonart, P; Taljaard, L; Mengu, M; Franz, C M A P; Holzapfel, W H

2006-12-26

432

Phylogenetic group- and species-specific oligonucleotide probes for single-cell detection of lactic acid bacteria in oral biofilms  

PubMed Central

Background The purpose of this study was to design and evaluate fluorescent in situ hybridization (FISH) probes for the single-cell detection and enumeration of lactic acid bacteria, in particular organisms belonging to the major phylogenetic groups and species of oral lactobacilli and to Abiotrophia/Granulicatella. Results As lactobacilli are known for notorious resistance to probe penetration, probe-specific assay protocols were experimentally developed to provide maximum cell wall permeability, probe accessibility, hybridization stringency, and fluorescence intensity. The new assays were then applied in a pilot study to three biofilm samples harvested from variably demineralized bovine enamel discs that had been carried in situ for 10 days by different volunteers. Best probe penetration and fluorescent labeling of reference strains were obtained after combined lysozyme and achromopeptidase treatment followed by exposure to lipase. Hybridization stringency had to be established strictly for each probe. Thereafter all probes showed the expected specificity with reference strains and labeled the anticipated morphotypes in dental plaques. Applied to in situ grown biofilms the set of probes detected only Lactobacillus fermentum and bacteria of the Lactobacillus casei group. The most cariogenic biofilm contained two orders of magnitude higher L. fermentum cell numbers than the other biofilms. Abiotrophia/Granulicatella and streptococci from the mitis group were found in all samples at high levels, whereas Streptococcus mutans was detected in only one sample in very low numbers. Conclusions Application of these new group- and species-specific FISH probes to oral biofilm-forming lactic acid bacteria will allow a clearer understanding of the supragingival biome, its spatial architecture and of structure-function relationships implicated during plaque homeostasis and caries development. The probes should prove of value far beyond the field of oral microbiology, as many of them detect non-oral species and phylogenetic groups of importance in a variety of medical conditions and the food industry.

2011-01-01

433

A description of the lactic acid bacteria microbiota associated with the production of traditional fermented vegetables in Vietnam.  

PubMed

An important part of the daily nourishment in Vietnam constitutes of fermented vegetables. Bacteria and especially lactic acid bacteria play a central role in the production of many fermented vegetables. The current study was conducted to investigate the diversity of native lactic acid bacteria (LAB) populations in 'dua muoi' (mustard and beet fermentation) and 'ca muoi' (eggplant fermentation), three types of popular traditional fermented vegetables of Vietnamese origin. To this end a polyphasic approach combining matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and pheS gene sequence analysis was used. In addition, denaturing gradient gel electrophoresis was performed as a culture-independent method to complement the observed culturable diversity data. A total of 881 LAB isolates were recovered from 21 different samples. Predominant LAB associated with 'dua muoi' and 'ca muoi' were identified as Lactobacillus fermentum (56.6%), Lactobacillus pentosus (24.4%) and Lactobacillus plantarum (17.1%). Less abundant species were Pediococcus pentosaceus (1.0%) and Lactobacillus brevis (0.5%). Species present less than 0.1% included Lactobacillus paracasei, Lactobacillus pantheris and Pediococcus acidilactici. In contrast to fermented mustard and beet with the highest prevalence of L. fermentum, the species most recovered from fermented eggplant samples was L. pentosus. In addition, an important degree of genetic variability within the different predominant species was observed and strain dependency correlating with the type of fermented vegetable or location of production could be demonstrated using multivariate statistics. This research gives an extensive and detailed inventory of the LAB diversity associated with the production of diverse Vietnamese fermented vegetables and demonstrates the influence of type of raw material and/or production location and conditions on this diversity. PMID:23500611

Nguyen, Doan Thi Lam; Van Hoorde, Koenraad; Cnockaert, Margo; De Brandt, Evie; Aerts, Maarten; Binh Thanh, Le; Vandamme, Peter

2013-02-04

434

Comparison between rinse and crush-and-rub sampling for aerobic bacteria recovery from broiler hatching eggs after sanitization.  

PubMed

This study compared surface and deep eggshell aerobic bacteria recovered by the rinse and crush-and-rub sampling methods for commercial hatching eggs after treatment with sanitizers. Eggs were arranged into 5 treatments consisting of no treatment, water, and 3 sanitizers. The sanitizers were H(2)O(2), phenol, and Q(4)B (a compound chemical containing 4 quaternary ammoniums and 1 biguanide moiety). Eggs were sprayed according to treatment and allowed to dry for 1 h before sampling. To collect samples for the eggshell rinse, each egg was massaged in a plastic bag with 20 mL of saline. Eggshells were then aseptically opened and their contents were discarded before being individually crushed into 50-mL centrifuge tubes containing 20 mL of saline. Aerobic bacteria were enumerated on Petrifilm after 48 h of incubation at 37°C. Aerobic bacteria recovered (log(10) cfu/mL) from the eggshell rinse were highest and similar for the no-treatment (4.0) and water (3.7) groups, lower for the phenol (3.2) and H(2)O(2) (3.1) groups, and lowest for the Q(4)B (2.4) group. Aerobic bacteria levels with the crush-and-rub method were similar for the no-treatment (2.5) and water (2.3) groups, lower for the phenol (1.6) group, intermediate for the H(2)O(2) (1.2) group, and lowest for the Q(4)B (0.9) group. The overall correlation between the rinse and crush-and-rub sampling methods for individual egg aerobic bacteria counts was r = 0.71. The correlation within each treatment revealed the following r values: no treatment, 0.55; water, 0.72; H(2)O(2), 0.67; phenol, 0.73; and Q(4)B, 0.38. A second experiment was designed to further examine the lower aerobic bacterial levels recovered by the crush-and-rub method (for previously rinsed eggs) than the levels recovered in the initial eggshell rinse sample. Eggs were either rinsed and then crushed and rubbed, or they were only crushed and rubbed without a prior rinse. Results confirmed a significant decrease (1.5 log(10) cfu/mL) in bacteria levels between the initial rinse (4.4) and the subsequent crush and rub (2.9) for the same eggshell. For the crush-and-rub eggs with no previous rinsing, the bacteria recovery level (3.9) was not significantly different from levels for the rinse method. Therefore, either the rinse or crush-and-rub sampling methods can be used to recover similar levels of eggshell aerobic bacteria. PMID:21673179

Spickler, J L; Buhr, R J; Cox, N A; Bourassa, D V; Rigsby, L L

2011-07-01

435

Diversity of lactic acid bacteria from modified atmosphere packaged sliced cooked meat products at sell-by date assessed by PCR-denaturing gradient gel electrophoresis.  

PubMed

The predominant lactic acid bacteria (LAB) microbiota associated with three types of modified atmosphere packaged (MAP) sliced cooked meat products (i.e. ham, turkey and chicken) was analyzed at sell-by date using a combination of culturing and molecular population fingerprinting. Likewise routine analyses during industrial MAP production, meat samples were plated on the general heterotrophic Plate Count Agar (PCA) and on the LAB-specific de Man, Rogosa, Sharpe (MRS) agar under different temperature and atmosphere conditions. Subsequently, community DNA extracts were prepared from culturable bacterial fractions harvested from both media and used for PCR targeting the V3 hyper-variable region of the 16S rRNA gene followed by denaturing gradient gel electrophoresis (DGGE) of PCR amplicons (PCR-DGGE). Irrespective of aerobic or anaerobic incubation conditions, V3-16S rDNA DGGE fingerprints of culturable fractions from PCA and MRS medium displayed a high level of similarity indicating that LAB constituted the most dominant group in the culturable bacterial community. Comparison of DGGE profiles of fractions grown at 20, 28 or 37 degrees C indicated that part of the culturable community consisted of psychrotrophs. Four DGGE bands were common among cooked ham, turkey and chicken products, suggesting that these represent the microbiota circulating in the plant where all three MAP product types were sliced and packaged. Based on band sequencing and band position analysis using LAB reference strains, these four bands could be assigned to Lactobacillus sakei and/or the closely related Lactobacillus fuchuensis, Lactobacillus curvatus, Carnobacterium divergens and Leuconostoc carnosum. In conclusion, the PCR-DGGE approach described in this study allows to discriminate, identify and monitor core and occasional LAB microbiota of MAP sliced cooked meat products and provides valuable complementary information to the current plating procedures routinely used in industrial plants. PMID:19913685

Audenaert, Kris; D'Haene, Klaas; Messens, Kathy; Ruyssen, Tony; Vandamme, Peter; Huys, Geert

2009-05-04

436

Biodiversity of lactic acid bacteria in French wheat sourdough as determined by molecular characterization using species-specific PCR.  

PubMed

The lactic acid microflora of nine traditional wheat sourdoughs from the Midi-Pyrénées area (South western France) was previously isolated and preliminary characterized using conventional morphological and biochemical analysis. However, such phenotypic methods alone are not always reliable and have a low taxonomic resolution for identification of lactic acid bacteria species. In the present study, a total of 290 LAB isolates were identified by PCR amplification using different sets of specific primers in order to provide a thorough characterization of the lactic flora from these traditional French sourdoughs. Overall, the LAB isolates belonged to 6 genera: Lactobacillus (39%, 8 species), Pediococcus (38%, 1 species), Leuconostoc (17%, 2 species), Weissella (4%, 2 species), Lactococcus (1%, 1 species) and Enterococcus (<1%, 1 species) and 15 different species were detected: L. plantarum, L. curvatus, L. paracasei, L. sanfranciscensis, L. pentosus, L. paraplantarum, L. sakei, L. brevis, P. pentosaceus, L. mesenteroides, L. citreum, W. cibaria, W. confusa, L. lactis and E. hirae. Facultative heterofermentative LAB represent more than 76% of the total isolates, the main species isolated herein correspond to L. plantarum and P. pentosaceus. Obligate heterofermentative lactobacilli (L. sanfranciscencis, L. brevis) represent less than 3% of the total isolates whereas Leuconostoc and Weissella species represent 21% of the total isolates and have been detected in eight of the nine samples. Detection of some LAB species was preferentially observed depending on the isolation culture medium. The number of different species within a sourdough varies from 3 to 7 and original associations of hetero- and homofermentative LAB species have been revealed. Results from this study clearly confirm the diversity encountered in the microbial community of traditional sourdough and highlight the importance of LAB cocci in the sourdough ecosystem, along with lactobacilli. PMID:19651455

Robert, Hervé; Gabriel, Valérie; Fontagné-Faucher, Catherine

2009-07-12

437

Immobilized growing lactic acid bacteria with ? -carrageenan — locust bean gum gel  

Microsoft Academic Search

Summary A cell entrapment process using ?-carrageenan — locust bean gum gel is presented. Streptococcus thermophilus, Lactobacillus bulgaricus and S. lactis were immobilized in small gel beads (0.5–1.0 mm and 1.0–2.0 mm diameter) and fermentations in bench bioreactors were conducted. Viability of entrapped cells, lactose utilization, lactic acid production and cell release rates were measured during fermentation. The procedure was

Pascal Audet; Céline Paquin; Christophe Lacroix

1988-01-01

438

Growth and bacteriocin production by lactic acid bacteria in vegetable broth and their effectiveness at reducing Listeria monocytogenes in vitro and in fresh-cut lettuce  

Microsoft Academic Search

The fresh-cut fruit and vegetable industry is searching for alternatives to replace chemical treatments with biopreservative approaches that ensure the safety of the product and fulfil consumer preferences for minimally processed foods. In this study, the use of bacteriocins produced by lactic acid bacteria has been tested as a substitute for chemical disinfection of fresh-cut iceberg lettuce. First, the ability

Ana Allende; Beatriz Martínez; Victoria Selma; María I. Gil; Juan E. Suárez; Ana Rodríguez

2007-01-01

439

Diversity and technological properties of predominant lactic acid bacteria from fermented cassava used for the preparation of Gari, a traditional African food  

Microsoft Academic Search

Traditional fermentation of cassava is dominated by a lactic acid bacteria (LAB) population. Fermentation is important for improving product flavour and aroma as well as safety, especially by reduction of its toxic cyanogenic glucosides. The production of Gari from cassava in Benin typically occurs on a household or small industrial scale, and consequently suffers from inconsistent product quality and may

Melanie Kostinek; Ingrid Specht; Vinodh A. Edward; Ulrich Schillinger; Christian Hertel; Wilhelm H. Holzapfel; Charles M. A. P. Franz

2005-01-01