scholarly journals Sequencing of 185 Streptococcus thermophilus and identification of fermentation biomarkers

2020 ◽  
Author(s):  
Wenjun Liu ◽  
Linjie Wu ◽  
Jie Zhao ◽  
Weicheng Li ◽  
Yu Wang ◽  
...  

Abstract Streptococcus (S.) thermophilus is an important dairy starter in the production of fermented dairy products has important significance, from natural fermentation in the past to industrial production today. While the genetic architecture underlying S. thermophilus traits and phenotypes is largely unknown. Here, we sequenced 185 S. thermophilus strains, which isolated from natural fermented dairy products of China and Mongolia and using comparative genomic and genome wide association study to provide novel point for genetic architecture underlying its traits and phenotypes. Genome analysis of S. thermophilus showed association of phylogeny with environmental and phenotypic features and revealed clades with high acid production potential or with substantial genome decay. A few S. thermophilus isolated from areas with high chloramphenicol emissions had a chloramphenicol-resistant gene CatB8. Most importantly, we defined a growth score and identified a missense mutation G1118698T located at the gene AcnA that were both predictive of acidification capability of S. thermophilus. Our findings provide novel insight in S. thermophilus genetic traits, antibiotic resistant and predictive of acidification capability which both may had huge help in culture starter screening.

2005 ◽  
Vol 68 (11) ◽  
pp. 2295-2300 ◽  
Author(s):  
WU DING ◽  
HAIFENG WANG ◽  
MANSEL W. GRIFFITHS

Lactobacilli and bifidobacteria are important members of the gastrointestinal microflora of humans and animals and are thought to have positive effects on human health. Therefore, there is an increasing interest in using these microorganisms as probiotics to be incorporated into either fermented dairy products or tablets. However, convincing scientific data that support claims of their health benefits are scarce. The effect of cell-free extracts of milk fermented by 10 probiotic bacteria (five Bifidobacterium strains and five Lactobacillus strains) on the expression of the flaA gene of Campylobacter jejuni was assessed using a fusion between the flaA σ28 promoter and a promoterless luxCDABE cassette carried on the plasmid pRYluxCDABE, which resulted in strains with quantifiable luminescence linked to flaA σ28 promoter activity. Cell-free extracts of milk fermented by all of the tested probiotic strains inhibited the growth of the C. jejuni and down-regulated flaA σ28 promoter activity. Two nonprobiotic lactic acid bacterial strains, Lactococcus lactis and Streptococcus thermophilus, were less inhibitory.


2020 ◽  
Author(s):  
Narges Dargahi ◽  
Joshua Johnson ◽  
Vasso Apostolopoulos

ABSTRACTIngesting probiotics contributes to the development of a healthy microflora in the gastrointestinal tract with established benefits to human health. Some of these beneficial effects may be through modulating of the immune system and probiotics have become more common in the treatment of many inflammatory and immune disorders. We demonstrate a range of immune modulating effects of Streptococcus thermophilus by human monocytes, including, decreased mRNA expression of IL-1R, IL-18, IFNγR1, IFNαR1, CCL2, CCR5, TLR-1, TLR-2, TLR-4, TLR-5, TLR-6, TLR-8, CD14, CD86, CD4, ITGAM, LYZ, TYK2, IFNR1, IRAK-1, NOD2, MYD88, ITGAM, SLC11A1, and, increased expression of IL-1α, IL-1β, IL-2, IL-6, IL-8, IL-23, IFNγ, TNFα, CSF-2. Routine administration of Streptococcus thermophilus in fermented dairy products, and their consumption may be beneficial to the treatment/management of inflammatory and autoimmune diseases.


Author(s):  
Ina Simiţaru ◽  
Rodica Segal

The exopolysaccharides produced by the lactic acid bacteria confer the possibility to obtain fermented dairy products of good quality, with desirable rheological properties, and diverse benefits for health. The capacity of lactic acid bacteria to produce exopolysaccharides is influenced by culture media and the conditions of growth. The purpose of this work was to study the thermophile yogurt culture YF-L 811, which contains Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. The study was based on the capacity of the culture to produce exopolysaccharides in different temperature conditions and with different ingredients added in culture media. The amount of exopolysaccharides was correlated to viscosity of the yogurt.


Biologics ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 396-415
Author(s):  
Narges Dargahi ◽  
Joshua C. Johnson ◽  
Vasso Apostolopoulos

Ingesting probiotics contributes to the development of a healthy microflora in the GIT with established benefits to human health. Some of these beneficial effects may be through the modulation of the immune system. In addition, probiotics have become more common in the treatment of many inflammatory and immune disorders. Here, we demonstrate a range of immune modulating effects of Streptococcus thermophilus by human monocytes, including decreased mRNA expression of IL-1R, IL-18, IFNαR1, IFNγR1, CCL2, CCR5, TLR-1, TLR-2, TLR-4, TLR-5, TLR-6, TLR-8, CD14, CD86, CD4, ITGAM, LYZ, TYK2, IFNR1, IRAK-1, NOD2, MYD88, SLC11A1, and increased expression of IL-1α, IL-1β, IL-2, IL-6, IL-8, IL-23, IFNγ, TNFα, CSF-2. The routine administration of Streptococcus thermophilus in fermented dairy products and their consumption may be beneficial to the treatment/management of inflammatory and autoimmune diseases.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Xue Han ◽  
Zhe Yang ◽  
Xueping Jing ◽  
Peng Yu ◽  
Yingchun Zhang ◽  
...  

19Streptococcus thermophiluswith high exopolysaccharide production were isolated from traditional Chinese fermented dairy products. The exopolysaccharide and viscosity of milk fermented by these 19 isolates were assayed. The strains ofStreptococcus thermophiluszlw TM11 were selected because its fermented milk had the highest exopolysaccharide content (380 mg/L) and viscosity (7716 mpa/s). ThenStreptococcus thermophiluszlw TM11 was combined withLactobacillus delbrueckiisubsp.bulgaricus3 4.5 and the combination was named SH-1. The quality of the yogurt fermented by SH-1 and two commercial starter cultures (YO-MIX 465, YF-L711) were compared. It was shown that the exopolysaccharide content of yogurt fermented by SH-1 was similar to that of yogurt fermented by YF-L711 and significantly higher than YO-MIX 465 (p<0.05). In addition, the yogurt fermented by SH-1 had the lowest syneresis (8.5%) and better texture and sensory than the samples fermented by YO-MIX 465 and YF-L711. It manifested that the selected higher exopolysaccharide production starter SH-1 could be used as yogurt starter and reduce the amount of adding stabilizer, which can compare with the imported commercial starter culture.


1992 ◽  
Vol 55 (12) ◽  
pp. 999-1002 ◽  
Author(s):  
R. JORDANO ◽  
CRISTINA E. SERRANO ◽  
MARÍA TORRES ◽  
J. SALMERON

Three M17 agar media for the enumeration of Streptococcus thermophilus in fermented dairy products, such as yogurt and other commercial fermented milk, were compared: CM785 Oxoid®, 15108 Merck®, and a M17 made in the laboratory. In all cases, the highest counts were taken on Oxoid® medium. The difference between the averages of the counts on the Oxoid® M17 and the laboratory-made M17 is significant, (P ≤ 0.05). However, the difference between the counts on the Oxoid® and Merck® media is not significant.


Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3669
Author(s):  
Dmitri Pismennõi ◽  
Vassili Kiritsenko ◽  
Jaroslav Marhivka ◽  
Mary-Liis Kütt ◽  
Raivo Vilu

Saccharides are the most common carbon source for Streptococcus thermophilus, which is a widely used bacterium in the production of fermented dairy products. The performance of the strain is influenced by the consumption of different saccharides during fermentation. Therefore, a precise measurement of the concentrations of saccharides in the fermentation media is essential. An 18-min long method with limits of quantitation in the range of 0.159–0.704 mg/L and with 13C labelled internal standards employing hydrophilic interaction chromatography coupled to mass spectrometric detection-(HILIC-LC-MS) allowed for simultaneous quantification of five saccharides: fructose, glucose, galactose, sucrose, and lactose in the fermentation samples. The method included a four-step sample preparation protocol, which could be easily applied to high-throughput analysis. The developed method was validated and applied to the fermentation samples produced by Streptococcus thermophilus.


2018 ◽  
Vol 20 (87) ◽  
pp. 78-84
Author(s):  
I.M. Slyvka ◽  
O.Y. Tsisaryk ◽  
L.Y. Musiy

Bacterial resistance to antimicrobials is a global health problem that affects not only on humane and veterinary medicine, but also on food products. The food chain can be by transmission of antibiotic resistance from bacterial populations to animals and humans. Literary data on the current state of the problem of antibiotic resistance of lactic acid bacteria (LAB) in Ukraine and in the world are given in the review. Possible ways of transferring resistance to antibiotics through fermented dairy products are shown. The main aspects of the danger of transmission of antibiotic resistance genes through the LAB and fermented dairy products are revealed. The main modern approaches to the definition of antibiotic resistance of microorganisms with the use of classical and modern research methods are described. The article provides the main sources of information on the safety of use of LAB as starter cultures and probiotics for the production of fermented dairy products. The hypothesis of the resistance gene's reservoir suggests that LAB can be a reservoir of sustainability genes, and the subsequent transfer of such genes to pathogenic and opportunistic microorganisms. The presence of antibiotic resistance genes transposed horizontally is inadmissible for lactobacilli, which are used as commercial bacterial agents for the production of fermented dairy products. According to the literature data, the absence of acquired antimicrobial resistance has become an important criterion for assessing the safety of lactobacilli, which are used as starting cultures for the production of fermented dairy products or probiotics. It has been established that it is obligatory to study the antibiotic resistance gene in addition to clinical and laboratory methods of studying the antibiotic resistance of LAB. To minimize the formation of antibiotic-resistant bacteria in food products of plant and animal origin it is possible by careful monitoring of residues of antibiotics in raw materials and finished products. This will prevent the entry of antibiotic resistant strains into the natural cycle.


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