scholarly journals Recombinant Oleate Hydratase from Lactobacillus rhamnosus ATCC 53103: Enzyme Expression and Design of a Reliable Experimental Procedure for the Stereoselective Hydration of Oleic Acid

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1122
Author(s):  
Antonio Castagna ◽  
Davide De Simeis ◽  
Erica E. Ferrandi ◽  
Stefano Marzorati ◽  
Daniela Monti ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Substrate Inhibition ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Strain ◽  
Hydration Reaction ◽  
E Coli ◽  
High Oleic ◽  
Oleic Acid Concentration ◽  
Microbial Strains ◽  
Oleate Hydratase

Different microbial strains are able to transform oleic acid (OA) into 10-hydroxystearic acid (10-HSA) by means of the catalytic activity of the enzymes oleate hydratase (EC 4.2.1.53). Lactobacillus rhamnosus ATCC 53103 performs this biotransformation with very high stereoselectivity, affording enantiopure (R)-10-HSA. In this work, we cloned, in Escherichia coli, the oleate hydratase present in the above-mentioned probiotic strain. Our study demonstrated that the obtained recombinant hydratase retains the catalytic properties of the Lactobacillus strain but that its activity was greatly affected by the expression procedure. According to our findings, we devised a reliable procedure for the hydration of oleic acid using a recombinant E. coli whole-cell catalyst. We established that the optimal reaction conditions were pH 6.6 at 28 °C in phosphate buffer, using glycerol and ethanol as co-solvents. According to our experimental protocol, the biocatalyst does not show significant substrate inhibition as the hydration reaction can be performed at high oleic acid concentration (up to 50 g/L).

scholarly journals Evaluation of a new probiotic concept for broilers

2020 ◽  
Author(s):  
S. L. Jørgensen ◽  
L. L. Poulsen ◽  
M. Bisgaard ◽  
H. Christensen
Keyword(s):  
Pathogenic Bacteria ◽  
Horizontal Transmission ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Strain ◽  
Average Weight ◽  
Normal Range ◽  
Multiple Introductions ◽  
E Coli ◽  
Probiotic Strains ◽  
The Cost

SUMMARYProbiotics were introduced as a spray directly in the hatcher when chickens started to leave the eggs which potentially could reduce the horizontal transmission and colonization with pathogenic bacteria. The single introduction of probiotics could limit the cost compared to multiple introductions with feed and/or water. A mixture of five probiotic strains belonging to Escherichia coli, Enterococcus faecalis, Lactobacillus agilis and Lactobacillus rhamnosus was tested with two independent flocks of broilers (Ross 308). For each experiment, a comparison was made to an untreated control flock on the same farm. At day 14 of production the probiotic strains were re-isolated from ileum of euthanized chickens. The first week mortality was slightly increased in the probiotic flock (0.42%) compared to the control (0.35%) in experiment 1, however, it was higher in the control flock (1.45%) compared to the probiotic flock (1.12%) in experiment 2. The average weight of chickens that could be slaughtered for consumption was increased by 3.5% in the probiotic flocks compared to the control flocks, resulting in a 1.9% higher total weight of slaughtered chickens in the probiotics treated flocks compared to the control as a mean of the two experiments. The number of condemned animals was within the normal range for the production system and could not directly be related to effects of probiotics. Although one probiotic strain of E. coli was isolated from dead animals, the probiotics did not affect the proportion of chickens which died due to E. coli during the first week compared to the control.Primary audienceplant managers, veterinarians, nutritionists

Differences in Development of Oleic and Linoleic Acid in High- and Normal-Oleic Virginia and Runner-Type Peanuts

2016 ◽  
Vol 43 (1) ◽  
pp. 12-23 ◽  
Author(s):  
C.M. Klevorn ◽  
K.W. Hendrix ◽  
T.H. Sanders ◽  
L.L. Dean
Keyword(s):  
Oleic Acid ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Food Industry ◽  
Growing Season ◽  
Fatty Acid Profiles ◽  
Fresh Weight ◽  
High Oleic ◽  
Harvest Dates ◽  
Oleic Acid Concentration

ABSTRACT A consistent, pure supply of high-oleic (HO) peanuts is important to certain segments of the food industry as it allows for the production of confections and other products with improved shelf-life characteristics. Peanut shellers have struggled with food industry demands for lots which contain greater than 95% high-oleic peanuts. Normal-oleic (NO) and HO cultivars of virginia and runner market type peanuts were grown during the 2012 and 2013 growing season respectively to investigate differences in fatty acid development between HO and NO peanuts. Fatty acid profiles of individual seeds from individual plants taken across the growing season were determined in relation to seed fresh weight. Fatty acid profiles of HO virginia-type seeds from the early sampling date of 78 days after planting (DAP) revealed oleic acid to linoleic acid ratios (O/L) of only 4.0 in the seeds of the greatest fresh weight. As the oleic acid concentration in many of the HO virginia-type peanuts reached 60 to 80% and the linoleic acid concentrations ranged from less than 1.0 to 10 % by the middle sampling date (106 DAP), the O/L ratios of most HO seeds were well above the industry accepted cut-off ratio of 9.0. A similar change in the fatty acids was seen in the HO runner cultivar. Increases in oleic acid and decreases in linoleic acid contents occurred in conjunction with the increased seed fresh weights. The data indicate that HO seed attain high-oleic status as physiological development progresses as seen in the changing seed fresh weight. However at the final sampling dates which corresponded to the harvest dates, O/L ratios of less than 9.0 were still present for the HO cultivars of both market types despite the fresh weight of some seeds being of potential marketable size. It was concluded that some of the perceived contamination of HO seed lots with NO seed could be the result of normal peanut development, especially in the virginia-type cultivar with the larger sized seeds.

The influence of oleic acid on cAMP accumulation of thyroid plasma membrane activated by thyrotropin

1988 ◽  
Vol 117 (1) ◽  
pp. 125-129
Author(s):  
Tien-Chun Chang ◽  
Tien-Shang Huang
Keyword(s):  
Plasma Membrane ◽  
Oleic Acid ◽  
Thyroid Hormone ◽  
Plasma Membranes ◽  
Albumin Concentration ◽  
Adenylate Cyclase System ◽  
Camp Accumulation ◽  
Hormone Binding ◽  
High Oleic ◽  
Oleic Acid Concentration

Abstract. Several thyroid hormone binding inhibitors have been described in nonthyroid illness. One of the major inhibitors, oleic acid, is present in excess amounts in sera of patients with nonthyroid illness. In this study, we demonstrated that oleic acid inhibited the cAMP accumulation of thyroid plasma membrane activated by thyrotropin at 50 μmol/l and higher concentrations. In the presence of albumin, oleic acid significantly inhibited the cAMP accumulation of plasma membrane activated by thyrotropin at 2.4 mmol/l (P < 0.01 when the albumin concentration was 40 g/l and pH was 7.4; P < 0.001 when the albumin concentration was 20 g/l and pH was 7.2). These findings suggest that in nonthyroid illness, especially at a low albumin concentration and low blood pH, a high oleic acid concentration may influence the thyroid function directly in addition to inhibiting the thyroid hormone binding to serum protein. Oleic acid also could inhibit 5′-guanylylimidodiphosphate- and forskolin-induced cAMP production in thyroid plasma membranes. Therefore, the inhibiting effect of oleic acid may be through the action of oleic acid on the catalytic unit of the hormone-sensitive adenylate cyclase system.

scholarly journals Measurements of Oleic Acid among Individual Kernels Harvested from Test Plots of Purified Runner and Spanish High Oleic Seed

2017 ◽  
Vol 44 (2) ◽  
pp. 134-142 ◽  
Author(s):  
J. P. Davis ◽  
J.M. Leek ◽  
D.S. Sweigart ◽  
P. Dang ◽  
C.L. Butts ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Acid Concentration ◽  
Kernel Size ◽  
Late Season ◽  
High Oleic ◽  
Chemistry Development ◽  
Oleic Acid Concentration ◽  
Soil Temperatures ◽  
Type Data ◽  
Kernel Level

ABSTRACT Normal oleic peanuts are often found within commercial lots of high oleic peanuts when sampling among individual kernels. Kernels not meeting high oleic threshold could be true contamination with normal oleic peanuts introduced via poor handling, or kernels not meeting threshold could be immature and not fully expressing the trait. Beyond unintentional mixing, factors contributing to variation in oleic acid concentration in peanut kernels include market type, environment, maturity and/or kernel size; however, the relative influence of these factors, and their interactions, is not quantitatively well understood on the single kernel level. To better understand these factors while simultaneously excluding variation from unintentional mixing, seed from a high oleic spanish cultivar and seed from a high oleic runner cultivar were carefully purified via NIR technology. The purified seed were planted in environmentally controlled test plots to analyze the progeny for oleic acid chemistry. Post flowering, plot sections were either chilled (3.8 -5.0 C below ambient), maintained at ambient or heated (3.8-5.0 C above ambient) in the pod zone to characterize soil temperature effects on oleic acid chemistry development. Fully randomized (4 reps) plots included the purified high oleic spanish and runner cultivars, three soil temperatures, seed maturity (profile board), commercial kernel size classifications, and a late season flower termination protocol. At harvest, the oleic acid concentration of approximately 24,000 individual kernels were measured via NIR technology. Market type, temperature, maturity and size had a significant effect on high oleic chemistry among kernels. Late season flower termination significantly, and positively, influenced high oleic chemistry of runner peanuts, minimized the number of immature kernels not meeting high oleic threshold and resulted in elevated and more consistent distributions in this key chemistry; distributions that were more similar to those of the more botanically determinate, but lower yielding, spanish market type. Data from this study improves our understanding of expected natural variation in high oleic chemistry and suggests late season flower termination of runner peanuts is a viable strategy to maximize high oleic chemistry on the single kernel level.

scholarly journals Lactobacillus rhamnosus and its cell-free culture supernatant differentially modulate inflammatory biomarkers in Escherichia coli-challenged human dendritic cells

2014 ◽  
Vol 111 (10) ◽  
pp. 1727-1737 ◽  
Author(s):  
Miriam Bermudez-Brito ◽  
Sergio Muñoz-Quezada ◽  
Carolina Gomez-Llorente ◽  
Fernando Romero ◽  
Angel Gil
Keyword(s):  
Escherichia Coli ◽  
Dendritic Cells ◽  
Inflammatory Cytokines ◽  
Culture Supernatant ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Strain ◽  
E Coli ◽  
Tgf Β1 ◽  
Cell Free Culture Supernatant ◽  
Pro Inflammatory Cytokines

The intestinal immune system maintains a delicate balance between immunogenicity against invading pathogens and tolerance to the commensal microbiota and food antigens. Different strains of probiotics possess the ability to finely regulate the activation of dendritic cells (DC), polarising the subsequent activity of T-cells. Nevertheless, information about their underlying mechanisms of action is scarce. In the present study, we investigated the immunomodulatory effects of a potentially probiotic strain, Lactobacillus rhamnosus CNCM I-4036, and its cell-free culture supernatant (CFS) on human DC challenged with Escherichia coli. The results showed that the levels of pro-inflammatory cytokines such as IL-1β, IL-6, IL-8 and IL-12p70 were higher in the cells treated with live L. rhamnosus than in the cells treated with the CFS. In the presence of E. coli, the supernatant was more effective than the probiotic bacteria in reducing the secretion of pro-inflammatory cytokines. In addition, live L. rhamnosus potently induced the production of transforming growth factor (TGF)-β1 and TGF-β2, whereas the CFS increased the secretion of TGF-β1. However, in the presence of E. coli, both treatments restored the levels of TGF-β. The probiotic strain L. rhamnosus CNCM I-4036 and its CFS were able to activate the Toll-like receptor signalling pathway, enhancing innate immunity. The two treatments induced gene transcription of TLR-9. Live L. rhamnosus activated the expression of TLR-2 and TLR-4 genes, whereas the CFS increased the expression of TLR-1 and TLR-5 genes. In response to the stimulation with probiotic/CFS and E. coli, the expression of each gene tested was notably increased, with the exception of TNF-α and NFKBIA. In conclusion, the CFS exhibited an extraordinary ability to suppress the production of pro-inflammatory cytokines by DC, and may be used as an effective and safer alternative to live bacteria.

scholarly journals Label-free quantitative proteomic analysis of the inhibition effect of Lactobacillus rhamnosus GG on Escherichia coli biofilm formation in co-culture

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Huiyi Song ◽  
Ni Lou ◽  
Jianjun Liu ◽  
Hong Xiang ◽  
Dong Shang
Keyword(s):  
Escherichia Coli ◽  
Proteomic Analysis ◽  
Biofilm Formation ◽  
Lactobacillus Rhamnosus ◽  
Differentially Expressed ◽  
Differentially Expressed Proteins ◽  
Label Free ◽  
Quantitative Proteomic Analysis ◽  
E Coli ◽  
Protein Ubiquitination

Abstract Background Escherichia coli (E. coli) is the principal pathogen that causes biofilm formation. Biofilms are associated with infectious diseases and antibiotic resistance. This study employed proteomic analysis to identify differentially expressed proteins after coculture of E. coli with Lactobacillus rhamnosus GG (LGG) microcapsules. Methods To explore the relevant protein abundance changes after E. coli and LGG coculture, label-free quantitative proteomic analysis and qRT-PCR were applied to E. coli and LGG microcapsule groups before and after coculture, respectively. Results The proteomic analysis characterised a total of 1655 proteins in E. coli K12MG1655 and 1431 proteins in the LGG. After coculture treatment, there were 262 differentially expressed proteins in E. coli and 291 in LGG. Gene ontology analysis showed that the differentially expressed proteins were mainly related to cellular metabolism, the stress response, transcription and the cell membrane. A protein interaction network and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis indicated that the differentiated proteins were mainly involved in the protein ubiquitination pathway and mitochondrial dysfunction. Conclusions These findings indicated that LGG microcapsules may inhibit E. coli biofilm formation by disrupting metabolic processes, particularly in relation to energy metabolism and stimulus responses, both of which are critical for the growth of LGG. Together, these findings increase our understanding of the interactions between bacteria under coculture conditions.

Fatty Acid Data and Crop Surveys Indicate Sources of Red Sunflower Seed Weevil (Coleoptera: Curculionidae), Populations and Suggest Strategies for Management

2020 ◽  
Author(s):  
Jarrad R Prasifka ◽  
Beth Ferguson ◽  
James V Anderson
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Sunflower Seed ◽  
Cultural Practices ◽  
High Oleic ◽  
Fatty Acid Data ◽  
Smicronyx Fulvus ◽  
Combined Data ◽  
Fatty Acid Compositions

Abstract The red sunflower seed weevil, Smicronyx fulvus L., is a univoltine seed-feeding pest of cultivated sunflower, Helianthus annuus L. Artificial infestations of S. fulvus onto sunflowers with traditional (&lt;25% oleic acid), mid-oleic (55–75%), or high oleic (&gt;80%) fatty acid profiles were used to test if fatty acids could be used as natural markers to estimate the proportion of weevils developing on oilseed sunflowers rather than wild Helianthus spp. and confection (non-oil) types. Oleic acid (%) in S. fulvus confirmed the fatty acid compositions of mature larvae and weevil adults reflected their diets, making primary (oleic or linoleic) fatty acids feasible as natural markers for this crop-insect combination. Oleic acid in wild S. fulvus populations in North Dakota suggests at least 84 and 90% of adults originated from mid-oleic or high oleic sunflower hybrids in 2017 and 2018, respectively. Surveys in 2017 (n = 156 fields) and 2019 (n = 120 fields) extended information provided by S. fulvus fatty acid data; no significant spatial patterns of S. fulvus damage were detected in samples, damage to oilseed sunflowers was greater than confection (non-oil) types, and the majority of damage occurred in ≈10% of surveyed fields. Combined, data suggest a few unmanaged or mismanaged oilseed sunflower fields are responsible for producing most S. fulvus in an area. Improved management seems possible with a combination of grower education and expanded use of non-insecticidal tactics, including cultural practices and S. fulvus-resistant hybrids.

Antimicrobial Screening, in Silico Studies and QSAR of Chalcone-based 1,4-disubstituted 1,2,3-triazole Hybrids

Drug Research ◽  
2020 ◽  
Author(s):  
Pinki Yadav ◽  
Kashmiri Lal ◽  
Ashwani Kumar
Keyword(s):  
Topoisomerase Ii ◽  
Antimicrobial Properties ◽  
Qsar Model ◽  
Quantitative Structure Activity Relationship ◽  
Binding Modes ◽  
E Coli ◽  
Structure Activity ◽  
In Silico Studies ◽  
Microbial Strains

AbstractThe in vitro antimicrobial properties of some chalcones (1a–1c ) and chalcone tethred 1,4-disubstituted 1,2,3-triazoles (2a–2u) towards different microbial strains viz. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Aspergillus niger and Candida albicans are reported. Compounds 2g and 2u exhibited better potency than the standard Fluconazole with MIC values of 0.0063 µmol/mL and 0.0068 µmol/mL, respectively. Furthermore, molecular docking was performed to investigate the binding modes of two potent compounds 2q and 2g with E. coli topoisomerase II DNA gyrase B and C. albicans lanosterol 14α-demethylase, respectively. Based on these results, a statistically significant quantitative structure activity relationship (QSAR) model was successfully summarized for antibacterial activity against B. subtilis.

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