A Foodgrade Preparation of Nisin from Diluted Milk Fermented with Lactococcus lactis W8

Lactococcus lactis strain W8, which contains the nisin Z gene in its genome, grew well and produced nisin in cow's milk at temperatures of 30 to 37°C. Maximum production of nisin was achieved at 6 h and was 4,000 activity units (AU) per ml in skim milk and 2,400 AU/ml in 3% fat milk. The organism produced nisin even in 20 times diluted skim milk and 3% fat milk at 1,000 and 600 AU/ml, respectively. Boiling of the fermented milk (pH 4.2) made with this culture allowed the separation of the liquid part (whey) from the curd. When 20 times diluted skim milk was fermented and the whey derived from it was lyophilized, the yield of nisin was 60,000 AU/g. The antimicrobial activity of the nisin preparation was stable for at least 1 year at refrigeration temperature. L. lactis W8 may have significant applications in the food industry for a cost-effective natural nisin preparation.

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Antimicrobial activity of the Nisin Z producer Lactococcus lactis subsp. lactis Lc08 against Listeria monocytogenes in skim milk

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352013000500037 ◽

2013 ◽

Vol 65 (5) ◽

pp. 1554-1560 ◽

Cited By ~ 8

Author(s):

L.M. Perin ◽

R.O. Miranda ◽

A.C. Camargo ◽

M. Colombo ◽

A.F. Carvalho ◽

...

Keyword(s):

Antimicrobial Activity ◽

Listeria Monocytogenes ◽

Lactococcus Lactis ◽

Food Systems ◽

Skim Milk ◽

In Vitro Tests ◽

Lactococcus Lactis Subsp ◽

Ph Values ◽

Nisin Z

The presented study aimed to verify the effect of different pH values, enzyme solutions and heat treatments on the antimicrobial activity of the bacteriocinogenic strain Lactococcus lactis subsp. lactis Lc08 and to test their antimicrobial activity against Listeria monocytogenes in reconstituted skim milk at refrigeration temperatures. This strain was previously described as a nisin Z producer and capable of inhibiting L. monocytogenes growth in in vitro tests. The antimicrobial activity of the bacteriocin cell-free supernatant of Lc08 was sensitive to enzyme treatments (except papain). The pH values and heating (65ºC for 30min, 75ºC for 15s) had no apparent effect on the antimicrobial activity of the bacteriocin produced by Lc08. Only treatment at autoclave conditions result in loss of their antimicrobial activity. Lc08 presented antimicrobial activity against L. monocytogenes in the milk system after 12h at 25ºC. No effect was found at 7ºC. The results show the application viability of the Lc08 in food systems as a biopreservative against L. monocytogenes.

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Folate fortification of skim milk by a probiotic Lactococcus lactis CM28 and evaluation of its stability in fermented milk on cold storage

Journal of Food Science and Technology ◽

10.1007/s13197-014-1406-7 ◽

2014 ◽

Cited By ~ 2

Author(s):

Jayakumar Beena Divya ◽

Kesavan Madhavan Nampoothiri

Keyword(s):

Lactococcus Lactis ◽

Cold Storage ◽

Skim Milk ◽

Fermented Milk

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Draft Genome Sequence of the Plasmid-Free Lactococcus lactis subsp. lactis Strain LMG 19460

Genome Announcements ◽

10.1128/genomea.00210-17 ◽

2017 ◽

Vol 5 (16) ◽

Author(s):

Inês N. Silva ◽

Sofia Duarte ◽

Leonilde M. Moreira ◽

Gabriel A. Monteiro

Keyword(s):

Lactococcus Lactis ◽

Genome Sequence ◽

Draft Genome ◽

Cost Effective ◽

Draft Genome Sequence ◽

Delivery Vehicle ◽

Content Type ◽

Mucosal Delivery ◽

Therapeutic Molecules ◽

Lactis Strain

ABSTRACT We report here the draft genome sequence of the plasmid-free Lactococcus lactis subsp. lactis strain LMG 19460. This strain has potential application for a cost-effective production of food-grade plasmid DNA to use in DNA vaccines, produce recombinant proteins, and be used as a mucosal delivery vehicle of therapeutic molecules.

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Evaluation of Technological Attributes of Lactococcus lactis Cultures for Preparation of Dahi and Misti Dahi (Sweetened Dahi)

Asian Journal of Dairy and Food Research ◽

10.18805/ajdfr.dr-1632 ◽

2021 ◽

Author(s):

Vandna Kumari ◽

Narendra Kumar ◽

Surajit Mandal

Keyword(s):

Escherichia Coli ◽

Growth Rate ◽

Antimicrobial Activity ◽

Lactococcus Lactis ◽

Micrococcus Luteus ◽

Fermented Milk ◽

Zone Of Inhibition ◽

Milk Products ◽

Test Organisms ◽

Fermented Milk Products

Background: Dahi and Misti dahi are traditional Indian fermented milk products. The present study was aimed to evaluate the technological attributes of selected six Lactococcus lactis cultures namely NCDC 193, 125, 128, 94, 97 and 314 for preparation of Dahi and Misti dahi. Methods: Six Lactococcus lactis were collected and tested for acidification profile as well as growth rate was also determined in milk with (15%) and without sucrose. Their flavor producing ability, proteolytic ability by OPA method and antimicrobial activity against four spoilage causing microorganisms (Escherichia coli NCDC 134, Staphylococcus aureus NCDC 109, Micrococcus luteus NCDC 131 and Pseudomonas fluorescenes NCDC 316) were evaluated. Result: All the six cultures were able to grow and produce acidity in milk containing 15% sucrose and similar acidification profile as well as growth rate (K) were found in milk without sucrose. Cultures NCDC 193, 128 and 125 were found to produce flavoring compound (diacetyl). Proteolytic activity of the selected cultures ranged between 0.17 to 0.41 mg/mL of Leucine. Among six cultures three Lactococcus lactis cultures NCDC 314, 94 and 97 have shown zone of inhibition against all four test organisms.

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Combinational Antibacterial Activity of Nisin and 3-Phenyllactic Acid and Their Co-production by Engineered Lactococcus lactis

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.612105 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jiaheng Liu ◽

Rongrong Huang ◽

Qianqian Song ◽

Hui Xiong ◽

Juan Ma ◽

...

Keyword(s):

Antibacterial Activity ◽

Lactococcus Lactis ◽

Foodborne Pathogens ◽

Antimicrobial Agents ◽

Cost Effective ◽

Food Preservation ◽

Phenyllactic Acid ◽

Nisin Z ◽

Effective Performance ◽

Microbial Analysis

Nisin produced by certain Lactococcus lactis strains is commercially used in meat and dairy industries because of its effective antibacterial activity and food safety characteristics. It has been proved that the antibacterial activity could be enhanced when combined with other antimicrobial agents. In this study, we demonstrated that nisin and 3-phenyllactic acid (PLA) in combination displayed excellent combinational antibacterial activity against foodborne pathogens including S. xylosus and M. luteus. The potential application in food preservation was further verified via microbial analysis during the storage of meat and milk, and determination of strawberry rot rate. Scanning electron microscopy observation indicated a distinct mode of PLA with nisin, which may target at the dividing cell, contributing to their combinational antibacterial effect of nisin and PLA. Considering the positive results, a nisin-PLA co-producing strain was constructed based on the food-grade strain L. lactis F44, a nisin Z producer. By the knockout of two L-lactate dehydrogenase (LDH) and overexpression of D-LDHY25A, the yield of PLA was significantly increased 1.77-fold in comparison with the wild type. Anti-bacterial assays demonstrated that the fermentation product of the recombinant strain performed highly effective antibacterial activity. These results provided a promising prospect for the nisin-PLA co-expressing L. lactis in food preservation on account of its considerable antibacterial activity and cost-effective performance.

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Engineering of Bacillus subtilis 168 for Increased Nisin Resistance

Applied and Environmental Microbiology ◽

10.1128/aem.00943-09 ◽

2009 ◽

Vol 75 (21) ◽

pp. 6688-6695 ◽

Cited By ~ 17

Author(s):

Mette E. Hansen ◽

Romilda Wangari ◽

Egon B. Hansen ◽

Ivan Mijakovic ◽

Peter R. Jensen

Keyword(s):

Bacillus Subtilis ◽

Lactococcus Lactis ◽

Resistance Genes ◽

Food Industry ◽

Cost Effective ◽

Heterologous Production ◽

Host Organism ◽

Synthetic Promoter ◽

Bacillus Subtilis 168 ◽

Promoter Library

ABSTRACT Nisin is a natural bacteriocin produced commercially by Lactococcus lactis and widely used in the food industry as a preservative because of its broad host spectrum. Despite the low productivity and troublesome fermentation of L. lactis, no alternative cost-effective host has yet been found. Bacillus subtilis had been suggested as a potential host for the biosynthesis of nisin but was discarded due to its sensitivity to the lethal action of nisin. In this study, we have reevaluated the potential of B. subtilis as a host organism for the heterologous production of nisin. We applied transcriptome and proteome analyses of B. subtilis and identified eight genes upregulated in the presence of nisin. We demonstrated that the overexpression of some of these genes boosts the natural defenses of B. subtilis, which allows it to sustain higher levels of nisin in the medium. We also attempted to overcome the nisin sensitivity of B. subtilis by introducing the nisin resistance genes nisFEG and nisI from L. lactis under the control of a synthetic promoter library.

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Enzymatic-Ultraviolet Method for Measuring Lactose in Milk: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/67.3.637 ◽

1984 ◽

Vol 67 (3) ◽

pp. 637-640 ◽

Cited By ~ 1

Author(s):

David O Biltcliffe ◽

Dick H Kleyn ◽

J Richard Trout ◽

◽

D Azzara ◽

...

Keyword(s):

Food Industry ◽

Collaborative Study ◽

Skim Milk ◽

Gravimetric Method ◽

T Test ◽

Enzymatic Method ◽

Commercial Laboratory ◽

Aoac Method ◽

Standard Deviations

Abstract Collaborators in 8 dairy and food industry laboratories performed one lactose determination on each of 8 unknown samples of milk, lowfat milk, or skim milk, as 3 pairs of blind duplicates. Two known samples were provided to gain experience prior to analysis of the unknown samples. All of the above samples were also analyzed for lactose content by the official AOAC gravimetric method (16.507) by a commercial laboratory. From the overall mean of results on all samples, determinations by the enzymatic method averaged 0.49% lower than by the AOAC method. This difference was significant by the t-test (P = 0.05), which indicated a lack of agreement between the compared methods in determining lactose content. Standard deviations were similar for the 3 sets of blind duplicates which ranged between 3.67 and 4.55% lactose content. F-values revealed that variations between means obtained by laboratories differed significantly as compared with variations within laboratory means. The method has been adopted official first action.

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The Effects of Dietary Supplementation of Lactococcus lactis Strain Plasma on Skin Microbiome and Skin Conditions in Healthy Subjects—A Randomized, Double-Blind, Placebo-Controlled Trial

Microorganisms ◽

10.3390/microorganisms9030563 ◽

2021 ◽

Vol 9 (3) ◽

pp. 563

Author(s):

Ryohei Tsuji ◽

Kamiyu Yazawa ◽

Takeshi Kokubo ◽

Yuumi Nakamura ◽

Osamu Kanauchi

Keyword(s):

Gene Expression ◽

Lactococcus Lactis ◽

Healthy Subjects ◽

Controlled Trial ◽

Dietary Supplementation ◽

Skin Microbiome ◽

Double Blind ◽

Double Blind Placebo ◽

Lactis Strain ◽

Skin Conditions

(1) Background: Lactococcus lactis strain Plasma (LC-Plasma) is a unique strain which directly activates plasmacytoid dendritic cells, resulting in the prevention against broad spectrum of viral infection. Additionally, we found that LC-Plasma intake stimulated skin immunity and prevents Staphylococcus aureus epicutaneous infection. The aim of this study was to investigate the effect of LC-Plasma dietary supplementation on skin microbiome, gene expression in the skin, and skin conditions in healthy subjects. (2) Method: A randomized, double-blind, placebo-controlled, parallel-group trial was conducted. Seventy healthy volunteers were enrolled and assigned into two groups receiving either placebo or LC-Plasma capsules (approximately 1 × 1011 cells/day) for 8 weeks. The skin microbiome was analyzed by NGS and qPCR. Gene expression was analyzed by qPCR and skin conditions were diagnosed by dermatologists before and after intervention. (3) Result: LC-Plasma supplementation prevented the decrease of Staphylococcus epidermidis and Staphylococcus pasteuri and overgrowth of Propionibacterium acnes. In addition, LC-Plasma supplementation suggested to increase the expression of antimicrobial peptide genes but not tight junction genes. Furthermore, the clinical scores of skin conditions were ameliorated by LC-Plasma supplementation. (4) Conclusions: Our findings provided the insights that the dietary supplementation of LC-Plasma might have stabilizing effects on seasonal change of skin microbiome and skin conditions in healthy subjects.

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Electrochemical Biosensors in Food Safety: Challenges and Perspectives

Molecules ◽

10.3390/molecules26102940 ◽

2021 ◽

Vol 26 (10) ◽

pp. 2940

Author(s):

Antonella Curulli

Keyword(s):

Food Industry ◽

Electrochemical Sensors ◽

Cost Effective ◽

Electrochemical Biosensors ◽

Food Chains ◽

Sensing Systems ◽

Highly Sensitive ◽

Skilled Personnel ◽

Recent Developments ◽

Key Issues

Safety and quality are key issues for the food industry. Consequently, there is growing demand to preserve the food chain and products against substances toxic, harmful to human health, such as contaminants, allergens, toxins, or pathogens. For this reason, it is mandatory to develop highly sensitive, reliable, rapid, and cost-effective sensing systems/devices, such as electrochemical sensors/biosensors. Generally, conventional techniques are limited by long analyses, expensive and complex procedures, and skilled personnel. Therefore, developing performant electrochemical biosensors can significantly support the screening of food chains and products. Here, we report some of the recent developments in this area and analyze the contributions produced by electrochemical biosensors in food screening and their challenges.

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