scholarly journals Expression of DinJ-YafQ System of Lactobacillus casei Group Strains in Response to Food Processing Stresses

2019 ◽  
Vol 7 (10) ◽  
pp. 438
Author(s):  
Alessia Levante ◽  
Claudia Folli ◽  
Barbara Montanini ◽  
Alberto Ferrari ◽  
Erasmo Neviani ◽  
...  
Keyword(s):  
High Temperature ◽  
Food Processing ◽  
Dairy Products ◽  
Lactobacillus Casei ◽  
Stress Condition ◽  
Stress Conditions ◽  
Food Environments ◽  
Bacterial Genomes ◽  
Plate Counts ◽  
Related Stress

Toxin-antitoxin (TA) systems are widely distributed in bacterial genomes and are involved in the adaptive response of microorganisms to stress conditions. Few studies have addressed TA systems in Lactobacillus and their role in the adaptation to food environments and processes. In this work, for six strains belonging to L. casei group isolated from dairy products, the expression of DinJ-YafQ TA system was investigated after exposure to various food-related stresses (nutrient starvation, low pH, high salt concentration, oxidative stress, and high temperature), as well as to the presence of antibiotics. In particular, culturability and DinJ-YafQ expression were evaluated for all strains and conditions by plate counts and RT qPCR. Among all the food-related stress conditions, only thermal stress was capable to significantly affect culturability. Furthermore, exposure to ampicillin significantly decreased the culturability of two L. rhamnosus strains. The regulation of DinJ-YafQ TA system resulted strain-specific; however, high temperature was the most significant stress condition able to modulate DinJ-YafQ expression. The increasing knowledge about TA systems activity and regulation might offer new perspectives to understand the mechanisms that L. casei group strains exploit to adapt to different niches or production processes.

scholarly journals Comparison of biofilm formation between non-pathogenic Listeria strains under different stress conditions

2020 ◽  
Author(s):  
Endrit Hasani ◽  
Sabrine Labidi ◽  
Csilla Mohácsi-Farkas ◽  
Gabriella Kiskó
Keyword(s):  
Listeria Monocytogenes ◽  
Food Processing ◽  
Biofilm Formation ◽  
Stress Condition ◽  
Environmental Safety ◽  
Stress Conditions ◽  
Listeria Innocua ◽  
Meat Industry ◽  
Micro Organisms ◽  
Listeria Seeligeri

AbstractMicro-organisms can attach to food surfaces and develop biofilms which present a concern in food and environmental safety. The main goal of the current study was to investigate the biofilm formation of six non-pathogenic Listeria strains under different stress conditions using a microplate assay. The effect of the weak biofilm-forming non-pathogenic Listeria strains on the biofilm formation of a strong biofilm-forming pathogenic Listeria strain (Listeria monocytogenes #8) was also examined. Listeria innocua CCM4030, Listeria innocua 2885 and Listeria seeligeri/welshimeri 292 showed the same patterns of biofilm formation with increasing NaCl concentrations from 0.05 to 15%, but all the other strains showed a continuously decreasing trend of OD595 in the same conditions. This study showed that in the case of non-pathogenic Listeria strains, higher concentrations of NaCl do not present a stress condition that enhances biofilm formation. Decrease in pH inhibited biofilm formation for all the non-pathogenic Listeria strains. The weak biofilm forming non-pathogenic Listeria strains (Listeria innocua 2885 and Listeria innocua CCM4030) overgrew the strong biofilm-forming Listeria strain (Listeria monocytogenes #8) during biofilm formation. This phenomenon could be beneficial and potentially be used as a novel control strategy to prevent the colonization of the pathogenic Listeria at food processing facilities such as in meat industry.

ALUMINUM 214

Alloy Digest ◽  
1964 ◽  
Vol 13 (11) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Shear Strength ◽  
High Temperature ◽  
Physical Properties ◽  
Food Processing ◽  
Heat Treating ◽  
Temperature Performance ◽  
Aluminum Company ◽  
Excellent Corrosion Resistance ◽  
Marine Applications

Abstract Aluminum 214 is a non-heat treatable alloy containing 4% magnesium and characterized by excellent corrosion resistance and excellent weldability. It is recommended for marine applications and food processing equipment. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive and shear strength as well as fatigue. It also includes information on high temperature performance and corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Al-141. Producer or source: Aluminum Company of America.

scholarly journals Impact of the Resistance Responses to Stress Conditions Encountered in Food and Food Processing Environments on the Virulence and Growth Fitness of Non-Typhoidal Salmonellae

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 617
Author(s):  
Silvia Guillén ◽  
Laura Nadal ◽  
Ignacio Álvarez ◽  
Pilar Mañas ◽  
Guillermo Cebrián
Keyword(s):  
Stress Resistance ◽  
Food Processing ◽  
Current Knowledge ◽  
Foodborne Pathogen ◽  
Stress Conditions ◽  
Bacterial Cells ◽  
Modified Atmospheres ◽  
Development Of Resistance ◽  
Salmonella Virulence ◽  
Short Time

The success of Salmonella as a foodborne pathogen can probably be attributed to two major features: its remarkable genetic diversity and its extraordinary ability to adapt. Salmonella cells can survive in harsh environments, successfully compete for nutrients, and cause disease once inside the host. Furthermore, they are capable of rapidly reprogramming their metabolism, evolving in a short time from a stress-resistance mode to a growth or virulent mode, or even to express stress resistance and virulence factors at the same time if needed, thanks to a complex and fine-tuned regulatory network. It is nevertheless generally acknowledged that the development of stress resistance usually has a fitness cost for bacterial cells and that induction of stress resistance responses to certain agents can trigger changes in Salmonella virulence. In this review, we summarize and discuss current knowledge concerning the effects that the development of resistance responses to stress conditions encountered in food and food processing environments (including acid, osmotic and oxidative stress, starvation, modified atmospheres, detergents and disinfectants, chilling, heat, and non-thermal technologies) exerts on different aspects of the physiology of non-typhoidal Salmonellae, with special emphasis on virulence and growth fitness.

The CRZ-1 Transcription Factor Regulates Hsp 80 Involves in the Acquisition of Thermotolerance, and NCA-2 for Calcium Stress Tolerance in Neurospora Crassa

2021 ◽  
Author(s):  
Avishek Roy ◽  
Ranjan Tamuli
Keyword(s):  
Transcription Factor ◽  
Heat Shock ◽  
Neurospora Crassa ◽  
Stress Condition ◽  
Stress Conditions ◽  
Start Codon ◽  
Expression Levels ◽  
Heat Shock Stress ◽  
Shock Proteins ◽  
Shock Stress

Abstract Heat shock proteins (Hsps) are molecular chaperones and required for survival of organisms under heat stress conditions. In this study, we studied Hsp80, a member of the Hsp90 family, in Neurospora crassa. The expression of hsp80 was severely reduced in the N. crassa calcineurin B subunit RIP-mutant (cnb-1RIP) strains under the heat shock conditions. Furthermore, the expression levels of cnb-1, hsp60, hsp80, and the calcineurin-regulated transcription factor crz-1 were increased, but expression levels were reduced in the presence of the calcineurin inhibitor FK506 under the heat shock stress in the N. crassa wild type. Therefore, the calcineurin-crz-1 signaling pathway transcriptionally regulates hsp60 and hsp80 under the heat shock stress condition in N. crassa. In addition, the transcript levels of trm-9 and nca-2, a Ca2+ sensor and a Ca2+ ATPase, respectively, were increased under the heat shock stress condition. Moreover, the expression of the hsp80, but not the hsp60, was reduced in the Δtrm-9, Δnca-2, and the Δtrm-9 Δnca-2 double mutants. These results suggested that hsp80, trm-9, and nca-2 play a role in coping the heat shock stress in N. crassa. We found that CRZ-1 binds to 5ʹ-CCTTCACA-3ʹ and 5ʹ-AGCGGAGC-3ʹ 8 bp nucleotide sequences, located about 1075 bp and 679 bp upstream of the ATG start codon, respectively, of hsp80. We also found that CRZ-1 binds to an 8 bp nucleotide sequence 5ʹ-ACCGCGCC-3ʹ, located 234 bp upstream of the ATG start codon of nca-2 under Ca2+ stress condition. Thus, cnb-1, hsp60, hsp80, and crz-1 are involved in the heat shock stress response in N. crassa. Moreover, CRZ-1 upregulates the expressions of hsp80 and nca-2 under the heat shock stress and Ca2+ stress conditions, respectively, in N. crassa.

scholarly journals Vigor and alpha-amylase activity in common bean seeds under salt stress conditions

2021 ◽  
Vol 42 (6supl2) ◽  
pp. 3633-3650
Author(s):  
Matheus Santin Padilha ◽  
◽  
Cileide Maria Medeiros Coelho ◽  
Natalia Carolina Moraes Ehrhardt-Brocardo ◽  
◽  
...  
Keyword(s):  
Salt Stress ◽  
Common Bean ◽  
Stress Condition ◽  
Amylase Activity ◽  
Reduction Rate ◽  
Stress Conditions ◽  
Alpha Amylase ◽  
Reserve Mobilization ◽  
Relationship Of ◽  
The Relationship

Seeds with high vigor have greater capacity for hydrolysis and mobilization of stored reserves, which results in the formation of vigorous seedlings, and this behavior is observed under abiotic stress conditions. This study proposes to investigate the relationship of the enzyme alpha-amylase in lots of common-bean seeds with contrasting vigor, when subjected to the absence and presence of salt stress, aiming to identify the relationship of this enzyme with the vigor of the seed lot under these conditions. Seven common-bean cultivars were used. Physiological quality was determined by germination, vigor index and seedling length. The mobilization of reserves was evaluated under absence and presence of salt stress simulated with a NaCl solution with a concentration of 50 mmol L-1. The analyzed variables regarding reserve mobilization were reserve reduction, reserve reduction rate, seedling dry weight, reserve mobilization rate, starch, starch reduction rate and alpha-amylase activity. Results showed that the stress condition negatively affected all the evaluated variables; however, the cultivars classified as having greater vigor showed better physiological performance under stress. Salt stress in common-bean seeds affects seedling performance and reduces alpha-amylase activity during germination, and high-vigor seed lots exhibited higher enzyme activity in the no-stress condition.

scholarly journals Heritability and mode of gene action determination for grain filling rate and relative water content in hexaploid wheat

Genetika ◽  
2012 ◽  
Vol 44 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Ahmad Golparvar
Keyword(s):  
Drought Stress ◽  
Water Content ◽  
Relative Water Content ◽  
Stress Condition ◽  
Gene Action ◽  
Grain Filling ◽  
Stress Conditions ◽  
Filling Rate ◽  
Grain Filling Rate ◽  
Relative Water

Mode of gene action, heritability and determination of the effective breeding strategy for improvement of physiological and traits specifically in drought stress conditions is very important. Therefore, this study was conducted by using two drought susceptible and tolerant wheat cultivars. Cultivars Sakha8 (tolerant) and Pishtaz (susceptible) as parents along with F1, F2, BC1 and BC2 generations were sown in a randomized complete block design with three replications in drought stress conditions. Results of analysis of variance indicated significant difference between generations as well as degree of dominance revealed over-dominance for the both traits. Fitting simple additive-dominance model designated that this model was not able to account for changes of traits relative water content and mean of grain filling rate. It was revealed that m-d-h-i-j model for relative water content and m-d-h-i model for mean of grain filling rate are the best models. Estimation of heritability and mode of gene action indicated that selection for improvement of traits studied in stress condition and specifically in early generations have medium genetic gain. In conclusion, grain filling rate is better than relative water content as indirect selection criteria to improve plant grain yield in drought stress condition.

scholarly journals Manufacturing of Fermented dairy products by using Lactobacillus casei which had the ability to lower cholesterol

2010 ◽  
Vol 4 (1) ◽  
pp. 72-81
Author(s):  
Abdul Wahed Baker ◽  
Zaid A. A. ◽  
Amer A. A.
Keyword(s):  
Shelf Life ◽  
Dairy Products ◽  
Lactobacillus Casei ◽  
Storage Period ◽  
Bacterial Cells ◽  
Manufactured Products ◽  
Fermented Dairy Products ◽  
Therapeutic Properties ◽  
Fermented Dairy ◽  
Number Of Bacteria

The study included manufacturing of fermented dairy products by using full cream milk of four kinds of mammalian: (Buffalos, Cows, Sheep's and Goats); with the use of Lactobacillus casei as a starter for the production of fermented dairy products which had the ability to lower cholesterol percentage in the above mentioned products by (71.4, 70, 74.8 and 67.7)% respectively. The viability of Lb. casei had not been affected significantly during storage shelf life of 21days " The product shelf life " , keeping their therapeutic properties unaltered with high viable number of bacteria at time of consumption. The viable counts of the bacteria after storage period for manufactured products were (1.06× 109, 8.1× 108, 7.5× 108and 8× 108) CFU/ml respectively. These numbers represent a decrease equal to one logarithmic cycle for each of manufactured products of Cows, Sheep's and Goats milk, and the decrease of bacteria's viability of manufactured products of Buffalos milk was less than one logarithmic cycle. Results of statistical analysis showed that there was highly significant differences (P<0.05) in the viable bacterial cells counts between manufactured products. By sensory comparison of the manufactured fermented products together, the results shows that the manufactured products from Buffalos milk was the best then the manufactured products of Cows milk then Sheep's milk then goats milk

scholarly journals The Liriodendron chinense MKK2 Gene Enhances Arabidopsis thaliana Salt Resistance

Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1160
Author(s):  
Xinying Chen ◽  
Pengkai Wang ◽  
Fangfang Zhao ◽  
Lu Lu ◽  
Xiaofei Long ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Mechanical Damage ◽  
Salt Resistance ◽  
Stress Conditions ◽  
Mitogen Activated Protein Kinase ◽  
Biotic And Abiotic Stress ◽  
Regulatory Pathways ◽  
Mitogen Activated Protein ◽  
Liriodendron Chinense ◽  
Related Stress

To adapt and sense environmental perturbations, including a variety of biotic and abiotic stress conditions, plants have developed disparate regulatory pathways. Mitogen-activated protein kinase (MAPK or MPK) signaling cascades are found widespread across the eukaryotic kingdoms of life. In plants, they may regulate signaling pathways aimed at resisting the stressful effects of low temperature, salt damage, drought, touch, and mechanical damage. To date, no conclusive studies into Liriodendron chinense (Hemsl.) Sarg MPK-related stress resistance signaling have been performed. In our study, we cloned three homologous L. chinense MAP kinase kinase family genes: LcMKK2, LcMKK4, and LcMKK6. LcMKK2 and LcMKK6 have their highest expression level in the root, while LcMKK4 is highly expressed in the stem. LcMKK2 showed upregulation in response to salt and cold stress conditions in L. chinense. To further analyze its gene function, we overexpressed LcMKK2 in wild-type Arabidopsis thaliana (L.) Heynh. and obtained transgenic plants. Overexpression of LcMKK2 caused a significant reduction in plant mortality (from 96% to 70%) in response to a 7-day 200 mM NaCl treatment. Therefore, we conclude that LcMKK2 is involved in a signaling response to salt stress, and it could thus prove an effective target gene for breeding strategies to improve Liriodendron salt tolerance.

WHAT THE SANITARIAN SHOULD KNOW ABOUT STAPHYLOCOCCI AND SALMONELLAE IN NON-DAIRY PRODUCTS.

1968 ◽  
Vol 31 (4) ◽  
pp. 110-116 ◽  
Author(s):  
Frank L. Bryan
Keyword(s):  
Food Processing ◽  
Dairy Products ◽  
Food Service ◽  
Infectious Agent ◽  
Control Measures ◽  
Processing Conditions ◽  
Inhibition Of Growth ◽  
Processing Plants ◽  
Prepared Food ◽  
Human Nose

After a review of the nature of staphylococci and staphylococcal enterotoxins including data on survival of these organisms under both natural and food processing conditions, the epidemiology of staphylococcal intoxications is discussed. The human nose is the main reservoir of Staphylococcus aureus. A number of circumstances must be fulfilled for foodborne staphylococcal intoxications to occur; these include: a reservoir for the infectious agent, a mode of dissemination of the organism, contamination of a food capable of supporting bacterial growth, enough time at a temperature which permits bacterial multiplication, and ingestion of sufficient amounts of staphylococcal enterotoxin by susceptible hosts. Control measures must be based on these circumstances. Principles of control, therefore, include limitation of contamination, inhibition of growth, and destruction of the organism. Control of staphylococcal intoxication must be emphasized at places foods are prepared (food processing plants, food-service establishments, and homes).

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