Stimulation of Bacteriocin Production by Dialyzed Culture Media from Different Lactic Acid Bacteria

In the present study, the antibacterial effect of 20 lactic acid bacteria isolates from a traditional cheese was investigated. 6 isolates showed antibacterial effect against Gram positive bacteria.Streptococcus thermophilusT2 strain showed the wide inhibitory spectrum against the Gram positive bacteria. Growth and bacteriocin production profiles showed that the maximal bacteriocin production, byS. thermophilusT2 cells, was measured by the end of the late-log phase (90 AUml−1) with a bacteriocine production rate of 9.3 (AUml−1)h−1. In addition, our findings showed that the bacteriocin, produced byS. thermophilusT2, was stable over a wide pH range (4–8); this indicates that such bacteriocin may be useful in acidic as well as nonacidic food. This preliminarily work shows the potential application of autochthonous lactic acid bacteria to improve safety of traditional fermented food.

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Suppression of bacteriocin production in mixed-species cultures of lactic acid bacteria

Food Control ◽

10.1016/j.foodcont.2012.09.014 ◽

2013 ◽

Vol 30 (2) ◽

pp. 474-479 ◽

Cited By ~ 13

Author(s):

Jesús Domínguez-Manzano ◽

Rufino Jiménez-Díaz

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bacteriocin Production ◽

Mixed Species

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Inactivation of Calcium-Dependent Lactic Acid Bacteria Phages by Phosphates

Journal of Food Protection ◽

10.4315/0362-028x-70.6.1518 ◽

2007 ◽

Vol 70 (6) ◽

pp. 1518-1522 ◽

Cited By ~ 8

Author(s):

V. B. SUÁREZ ◽

M. L. CAPRA ◽

M. RIVERA ◽

J. A. REINHEIMER

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Sodium Tripolyphosphate ◽

Culture Media ◽

Divalent Cations ◽

Skim Milk ◽

Inhibitory Effect ◽

Lytic Cycle ◽

High Solubility ◽

Calcium Dependent

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.

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Screening and enumeration of lactic acid bacteria in milk using three different culture media in Petrifilm™ Aerobic Count plates and conventional pour plate methodology

Journal of Dairy Research ◽

10.1017/s002202990700266x ◽

2007 ◽

Vol 74 (4) ◽

pp. 387-391 ◽

Cited By ~ 14

Author(s):

Maria BT Ortolani ◽

Gabriela N Viçosa ◽

Vanerli Beloti ◽

Luís A Nero

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Culture Media ◽

Skim Milk ◽

Raw Milk ◽

Excellent Correlation ◽

Anaerobic Conditions ◽

Milk Samples ◽

Experimental Inoculation

This study aimed to compare Petrifilm™ Aerobic Count (AC) plates and the conventional pour plate methodology using de Mann-Rogosa-Sharpe (MRS), Kang-Fung (KF) and Kang-Fung-Sol (KFS) culture media for screening and enumeration of lactic acid bacteria (LAB) in milk. Suspensions of 10 LAB species in reconstituted powder skim milk and 30 raw milk samples, without experimental inoculation, were tested. For selective enumeration, all samples were previously diluted in MRS, KF and KFS broths and then plated in Petrifilm™ AC and conventional pour plate methodology, using the same culture media with added agar. All plates were incubated at 37°C for 48 h in anaerobic conditions. Differences in the counts were observed only for raw milk samples using KFS in conventional methodology, when compared with the counts obtained from MRS and KF (P⩽0·05). The results showed excellent correlation indexes between both methodologies using the three culture media for LAB suspensions (r=0·97 for MRS, KF and KFS). For raw milk samples, the correlation indexes were excellent (r=0·97, for MRS) and good (r=0·84 for KF, and r=0·82 for KFS), showing some interference in Petrifilm™ AC when supplements were added, especially lactic acid. These results indicate the possibility of using Petrifilm™ AC plates for enumeration of LAB in milk, even with the use of selective supplements.

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Screening of lactic acid bacteria from sudanese fermented foods for bacteriocin production

Journal of Microbiology Biotechnology and Food Sciences ◽

10.15414/jmbfs.2015.4.5.373-378 ◽

2015 ◽

Vol 04 (05) ◽

pp. 373-378 ◽

Cited By ~ 5

Author(s):

Yasmeen Y. A. Elyas ◽

Nuha M. E. Yousif ◽

Isam A. Mohamed Ahmed

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bacteriocin Production ◽

Fermented Foods

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Antimicrobial Action of Hydrolyzed Chitosan against Spoilage Yeasts and Lactic Acid Bacteria of Fermented Vegetables

Journal of Food Protection ◽

10.4315/0362-028x-65.5.828 ◽

2002 ◽

Vol 65 (5) ◽

pp. 828-833 ◽

Cited By ~ 62

Author(s):

TONY SAVARD ◽

CAROLE BEAULIEU ◽

ISABELLE BOUCHER ◽

CLAUDE P. CHAMPAGNE

Keyword(s):

Molecular Weight ◽

Cell Wall ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Culture Media ◽

Antimicrobial Properties ◽

Spoilage Yeasts ◽

Entire Cell ◽

Fermented Vegetables ◽

Chitosan Lactate

The antimicrobial properties of various chitosan-lactate polymers (ranging from 0.5 to 1.2 MDa in molecular weight) against two yeasts isolated from fermented vegetables and against three lactic acid bacteria from a mixed starter for sauerkraut on methylene blue agar (MBA) and in vegetable juice medium (VJM) were investigated. Chitosan-lactate reduced the growth of all microorganisms in solid (MBA) as well as in liquid (VJM) medium. In MBA, a concentration of 5 g/liter was needed to inhibit the growth of Saccharomyces bayanus, while 1 g/liter was sufficient to inhibit the growth of Saccharomyces unisporus. Lactic acid bacteria were also inhibited in this range of concentrations. The low-molecular-weightchitosan-lactateDP3 (0.5 kDa) was most efficient in solid medium (MBA), and inhibitory activities decreased with increasing hydrolysate lengths. In liquid medium (VJM), 0.5 g of chitosan-lactate per liter reduced the growth rates for both yeasts, but 10 g/liter was insufficient to prevent yeast growth. Intermediate-molecular-weight chitosan-lactate (5 kDa) was more efficient than chitosan of low molecular weight. Native chitosan (1.2 MDa) showed no inhibition in either medium. Microscopic examination of S. unisporus Y-42 after treatment with chitosan-lactate DP25 showed agglutination of a refractive substance on the entire cell wall, suggesting an interaction between chitosan and the cell wall. When chitosanase was added to the culture media containing chitosan-lactate, refractive substances could not be observed.

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