scholarly journals PSIII-33 Stability and function of encapsulated Lactobacillus zeae for pig gut health

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 367-368
Author(s):  
Linyan Li ◽  
Xiaoyin Wang ◽  
Hai Yu ◽  
Qi Wang ◽  
Luca Lo Verso ◽  
...  

Abstract Lactobacilli have been used in livestock production to improve animal gut health; however, they are heat sensitive, which limits their use as feed additives. We have developed a novel spray-drying encapsulation technology that resulted in an approximately 0.5-log reduction of Lactobacillus zeae LB1, a probiotic bacterium known for its potential to reduce the infections caused by Salmonella and enterotoxigenic E. coli in vivo. In this study, encapsulated LB1 was evaluated for its stability during storage and feed pelleting and for its potential to modulate piglet performance. After 14-month storage at 4℃ and 22℃ in a sealed container, the survival rate of encapsulated LB1 represented 17.1% and 85.6% reduction of the original concentration, respectively. In the feed pelleting test, the survived non-encapsulated LB1 in pelleted or mash feed was 1-log lower in the concentration than encapsulated LB1 on the 7th and 30th day after pelleting. To examine the influence of LB1 alone or in combination with colostrum on pig performance, 80 newly-weaned piglets were equally allocated to five groups: 1) basal diets (control-CTL); 2) basal diets supplemented with non-encapsulated LB1 (NEP); 3) basal diets supplemented with encapsulated LB1 (EP); 4) basal diets supplemented with bovine colostrum (BC); 5) basal diets supplemented with EP and BC (EP-BC, same dose as in Group 3 or 4). No significant difference in growth performance was observed between the CTL group and other dietary treatments after five days’ treatment. Supplementation of LB1 or colostrum individually did not affect the population size of Lactobacillus in the ileum and colon of pigs. However, the EP-BC group had a significantly increased population of Lactobacillus in both the ileum and colon (94.57-fold and 23.51-fold, respectively) compared with the CTL group. In conclusion, our encapsulation technology can increase survival and delivery of Lactobacillus zeae potentially beneficial to piglet performance.

2021 ◽  
Author(s):  
man zhou

SMC (structural maintenance of chromosomes) complexes share conserved architectures and function in chromosome maintenance via an unknown mechanism. Here we have used single-molecule techniques to study MukBEF, the SMC complex in Escherichia coli. Real-time movies show MukB alone can compact DNA and ATP inhibits DNA compaction by MukB. We observed that DNA unidirectionally slides through MukB, potentially by a ratchet mechanism, and the sliding speed depends on the elastic energy stored in the DNA. MukE, MukF and ATP binding stabilize MukB and DNA interaction, and ATP hydrolysis regulates the loading/unloading of MukBEF from DNA. Our data suggests a new model for how MukBEF organizes the bacterial chromosome in vivo; and this model will be relevant for other SMC proteins.


2010 ◽  
Vol 73 (12) ◽  
pp. 2296-2300 ◽  
Author(s):  
SARAH L. EDMONDS ◽  
JAMES MANN ◽  
ROBERT R. McCORMACK ◽  
DAVID R. MACINGA ◽  
CHRISTOPHER M. FRICKER ◽  
...  

The risk of inadequate hand hygiene in food handling settings is exacerbated when water is limited or unavailable, thereby making washing with soap and water difficult. The SaniTwice method involves application of excess alcohol-based hand sanitizer (ABHS), hand “washing” for 15 s, and thorough cleaning with paper towels while hands are still wet, followed by a standard application of ABHS. This study investigated the effectiveness of the SaniTwice methodology as an alternative to hand washing for cleaning and removal of microorganisms. On hands moderately soiled with beef broth containing Escherichia coli (ATCC 11229), washing with a nonantimicrobial hand washing product achieved a 2.86 (±0.64)-log reduction in microbial contamination compared with the baseline, whereas the SaniTwice method with 62% ethanol (EtOH) gel, 62% EtOH foam, and 70% EtOH advanced formula gel achieved reductions of 2.64 ±0.89, 3.64 ±0.57, and 4.61 ±0.33 log units, respectively. When hands were heavily soiled from handling raw hamburger containing E. coli, washing with nonantimicrobial hand washing product and antimicrobial hand washing product achieved reductions of 2.65 ± 0.33 and 2.69 ± 0.32 log units, respectively, whereas SaniTwice with 62% EtOH foam, 70% EtOH gel, and 70% EtOH advanced formula gel achieved reductions of 2.87 ±0.42, 2.99 ± 0.51, and 3.92 ± 0.65 log units, respectively. These results clearly demonstrate that the in vivo antibacterial efficacy of the SaniTwice regimen with various ABHS is equivalent to or exceeds that of the standard hand washing approach as specified in the U.S. Food and Drug Administration Food Code. Implementation of the SaniTwice regimen in food handling settings with limited water availability should significantly reduce the risk of foodborne infections resulting from inadequate hand hygiene.


2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Sangwoo Park ◽  
Jung Wook Lee ◽  
Kevin Jerez Bogota ◽  
David Francis ◽  
Jolie Caroline González-Vega ◽  
...  

Abstract This study was conducted to investigate the effects of a direct-fed microbial (DFM) product (Bacillus subtilis strain DSM 32540) in weaned pigs challenged with K88 strain of Escherichia coli on growth performance and indicators of gut health. A total of 21 weaned pigs [initial body weight (BW) = 8.19 kg] were housed individually in pens and fed three diets (seven replicates per diet) for 21 d in a completely randomized design. The three diets were a corn-soybean meal-based basal diet without feed additives, a basal diet with 0.25% antibiotics (neo-Oxy 10-10; neomycin + oxytetracycline), or a basal diet with 0.05% DFM. All pigs were orally challenged with a subclinical dose (6.7 × 108 CFU/mL) of K88 strain of E. coli on day 3 of the study (3 d after weaning). Feed intake and BW data were collected on days 0, 3, 7, 14, and 21. Fecal scores were recorded daily. On day 21, pigs were sacrificed to determine various indicators of gut health. Supplementation of the basal diet with antibiotics or DFM did not affect the overall (days 0–21) growth performance of pigs. However, antibiotics or DFM supplementation increased (P = 0.010) gain:feed (G:F) of pigs during the post-E. coli challenge period (days 3–21) by 23% and 24%, respectively. The G:F for the DFM-supplemented diet did not differ from that for the antibiotics-supplemented diet. The frequency of diarrhea for pigs fed a diet with antibiotics or DFM tended to be lower (P = 0.071) than that of pigs fed the basal diet. The jejunal villous height (VH) and the VH to crypt depth ratio (VH:CD) were increased (P < 0.001) by 33% and 35%, respectively, due to the inclusion of antibiotics in the basal diet and by 43% and 41%, respectively due to the inclusion of DFM in the basal diet. The VH and VH:CD for the DFM-supplemented diet were greater (P < 0.05) than those for the antibiotics-supplemented diet. Ileal VH was increased (P < 0.05) by 46% due to the inclusion of DFM in the basal diet. The empty weight of small intestine, cecum, or colon relative to live BW was unaffected by dietary antibiotics or DFM supplementation. In conclusion, the addition of DFM to the basal diet improved the feed efficiency of E. coli-challenged weaned pigs to a value similar to that of the antibiotics-supplemented diet and increased jejunal VH and VH:CD ratio to values greater than those for the antibiotics-supplemented diet. Thus, under E. coli challenge, the test DFM product may replace the use of antibiotics as a growth promoter in diets for weaned pigs to improve feed efficiency and gut integrity.


2021 ◽  
Author(s):  
Jayashree Pohnerkar ◽  
Krishma Tailor ◽  
Prarthi Sagar ◽  
Keyur Dave

The guanosine nucleotide derivatives ppGpp and pppGpp are central to the remarkable capacity of bacteria to adapt to fluctuating environment and metabolic perturbations. These alarmones are synthesized by two proteins, RelA and SpoT in E. coli and the activities of each of the two enzymes are highly regulated for homeostatic control of (p)ppGpp levels in the cell. Although the domain structure and function of RelA are well defined, the findings of this study unfold the regulatory aspect of RelA that is possibly relevant in vivo. We uncover here the importance of the N-terminal 1-119 amino acids of the enzymatically compromised (p)ppGpp hydrolytic domain (HD) of monofunctional RelA for the (p)ppGpp mediated regulation of RelA-CTD function. We find that even moderate level expression of RelA appreciably reduces growth when the basal levels of (p)ppGpp in the cells are higher than in the wild type, an effect independent of its ability to synthesize (p)ppGpp. This is evidenced by the growth inhibitory effects of oversynthesis of the RelA-CTD in the relA+ strain but not in relA null mutant, suggesting the requirement of the functional RelA protein for basal level synthesis of (p)ppGpp, accordingly corroborated by the restoration of the growth inhibitory effects of the RelA-CTD expression in the relA1 spoT202 mutant. The N-terminal 119 amino acids of RelA fused in-frame with the RelA-CTD, both from 406-744 amino acids (including TGS) and from 454-744 amino acids (sans TGS) caused growth inhibition only in spoT1 and spoT202 relA1 mutants, uncovering the hitherto unrealized (p)ppGpp-dependent regulation of RelA-CTD function. An incremental rise in the (p)ppGpp levels is proposed to progressively modulate the interaction of RelA-CTD with the ribosomes, with possible implications in the feedback regulation of the N-terminal (p)ppGpp synthesis function, a proposal that best explains the nonlinear relationship between (p)ppGpp synthesis and increased ratio of RelA:ribosomes, both in vitro as well as in vivo.


2020 ◽  
Vol 10 (13) ◽  
pp. 4493
Author(s):  
Sung Won Choi ◽  
Hafiz Muhammad Shahbaz ◽  
Jeong Un Kim ◽  
Da-Hyun Kim ◽  
Sohee Yoon ◽  
...  

Efficiencies of various treatments for UVC photolysis (ultraviolet light-C at 254 nm), VUV photolysis (vacuum ultraviolet light at 254 nm and 185 nm), UVC-assisted titanium dioxide photocatalysis (UVC-TiO2), and VUV-assisted titanium dioxide photocatalysis (VUV-TiO2) were investigated for the degradation of pesticides including pyraclostrobin, boscalid, fludioxonil, and azoxystrobin and inactivation of microorganisms Escherichia coli K12 as a surrogate for E. coli O157:H7 and Saccharomyces cerevisiae in aqueous solutions and on the surface of fresh cut carrots. The degradation efficiencies of VUV were higher than for UVC on pesticides in aqueous solutions. However, there was no significant difference between degradation efficiencies for UVC and UVC-TiO2 treatments, and between VUV and VUV-TiO2 treatments. UVC, VUV, UVC-TiO2, and VUV-TiO2 showed similar inactivation effects against E. coli K12 and S. cerevisiae in aqueous solutions. The combined use of UVC and VUV treatments (combined UV) and combined use of UVC-TiO2 and VUV-TiO2 treatments (combined UV-TiO2) showed higher efficiencies (72–94% removal) for the removal of residual pesticides on fresh cut carrots than bubble water washing (53–73% removal). However, there was no significant difference in removal efficiency between combined UV and combined UV-TiO2 treatments. For E. coli K12 and S. cerevisiae on fresh cut carrots, the combined UV-TiO2 treatment (1.5 log and 1.6 log reduction, respectively) showed slightly higher inactivation effects than combined UV (1.3 log and 1.2 log reduction, respectively). Photolysis and TiO2 photocatalytic treatments under UV irradiation, including VUV as a light source, showed potential for the simultaneous degradation of pesticides and microorganisms as a non-chemical and residue-free technique for surface disinfection of fresh produce.


2018 ◽  
Vol 2017 (2) ◽  
pp. 612-620 ◽  
Author(s):  
Eithne O'Flaherty ◽  
Jeanne-Marie Membré ◽  
Enda Cummins

Abstract It is vital that harmful bacteria are removed from water and wastewater treatment plants to prevent human/environmental exposure. This paper examines the log reduction of antibiotic-sensitive (AS) and antibiotic-resistant (AR) Escherichia coli (E. coli) as a result of low-pressure (LP) and medium-pressure (MP) UV lamps. A meta-analysis was performed and a mixed-effect model was created in which 303 data points on the log reduction of E. coli from UV treatment were collected. The results show that in order to achieve a 6 log reduction using an MP lamp, on average a UV level of 7.3 mJ/cm2 for AS E. coli and 7.5 mJ/cm2 for AR E. coli were required. Using an LP lamp, a UV level of 8.1 mJ/cm2 for AS E. coli and 8.4 mJ/cm2 for AR E. coli were required. The results show there is no significant difference between the inactivation of AR and AS E. coli at different UV levels. The model predicts that AR or AS E. coli will be inactivated at UV levels lower than the recommended UV operation conditions (40 mJ/cm2), but it is important to use this UV level to inactivate other harmful microorganisms.


2020 ◽  
Vol 11 ◽  
Author(s):  
Zhengguo Zhang ◽  
Ziming Jiang ◽  
Yiming Zhang ◽  
Yu Zhang ◽  
Yan Yan ◽  
...  

Testicular macrophages (TM) play a central role in maintaining testicular immune privilege and protecting spermatogenesis. Recent studies showed that their immunosuppressive properties are maintained by corticosterone in the testicular interstitial fluid, but the underlying molecular mechanisms are unknown. In this study, we treated mouse bone marrow-derived macrophages (BMDM) with corticosterone (50 ng/ml) and uncovered AMP-activated protein kinase (AMPK) activation as a critical event in M2 polarization at the phenotypic, metabolic, and cytokine production level. Primary TM exhibited remarkably similar metabolic and phenotypic features to corticosterone-treated BMDM, which were partially reversed by AMPK-inhibition. In a murine model of uropathogenic E. coli-elicited orchitis, intraperitoneal injection with corticosterone (0.1mg/day) increased the percentage of M2 TM in vivo, in a partially AMPK-dependent manner. This study integrates the influence of corticosterone on M2 macrophage metabolic pathways, phenotype, and function, and highlights a promising new avenue for the development of innovative therapeutics for orchitis patients.


2010 ◽  
Vol 59 (3) ◽  
pp. 360-364 ◽  
Author(s):  
Liliana Pascual ◽  
Francisco Ruiz ◽  
Walter Giordano ◽  
Isabel Lucila Barberis

A strain of Lactobacillus, identified as Lactobacillus fermentum L23, was selected from among 100 strains isolated from vaginal swabs of healthy, non-pregnant, pre-menopausal women. L. fermentum L23 was chosen on the basis of its bacteriocinogenic ability and its properties relevant to colonization, i.e. self-aggregation, adherence to vaginal epithelial cells and co-aggregation with bacterial pathogens. The antimicrobial preventative and curative effects produced by the probiotic L. fermentum L23 administered locally against Escherichia coli in a murine vaginal tract infection model were studied. One dose of the human strain L23 containing 108 c.f.u. ml−1 colonized and persisted in the vaginal tract of the female BALB/c mice for 5 days. Infection with the pathogen at 106 c.f.u. ml−1 in the vaginal tract was maintained for more than 7 days. A single dose of L23 administered 24 h pre-infection inhibited E. coli growth on day 3 post-infection, showing the preventative effect displayed by this Lactobacillus strain. Treatment with L. fermentum L23 during the post-infection period showed complete inhibition of pathogen growth from day 5. Thus, this in vivo study indicated that the probiotic bacterium L. fermentum L23 produced both preventative and curative effects on E. coli growth. The beneficial properties and the production of antimicrobial metabolites may act in situ to inhibit a pathogenic micro-organism within the vaginal environment. Strain L23 could be a good natural alternative to other therapies used for genital infections.


2021 ◽  
Author(s):  
Enzo A Redondo ◽  
Leandro M Redondo ◽  
Octavio A Bruzzone ◽  
Juan M Diaz-Carrasco ◽  
Claudio Cabral ◽  
...  

Consumer demands and increased regulations on the use of antimicrobials in farm animals accentuated the need to develop strategies to replace antimicrobial growth promoters (AGPs) in food-producing animals. The present study evaluates the productive and gut health outcomes during the implementation of AGPs free programs based on the inclusion of a tannin blend compared with AGPs based program under commercial conditions. In the first trial, 6 farms were randomly assigned to AGP or tannin-based programs. In a second trial, both programs were applied simultaneously in one farm and the results were studied over 1 year. Although productive results from both trials were similar among treatments, evaluations of gut health indicators show improvements in the tannins treated flocks. Frequency and severity of intestinal gross lesions were reduced in jejunum (42% vs 23%; p<0.05 – 1.37 vs. 0.73; p<0.01, respectively) and ileum (25% vs. 10%; p<0.0.5 – 1.05 vs. 0.58; p<0.01) in tannins treated birds. Results from 16S studies, show that cecal microbiota diversity was not differentially affected by AGPs or tannins, but changes in the relative abundance of certain taxa were described, including Lactobacillus and Bifidobacterium groups. Additional evaluations using an in vivo model for C. perfringens necrotic enteritis showed that tannins treated birds had reduced incidence of gross lesions in jejunum (43.75 vs. 74.19%; p<0.01) and ileum (18.75% vs. 45.16%; p<0.05) compared with control. These results suggest that AGPs can be replaced by tannins feed additives, and contribute in the implementation of antimicrobial-free programs in broilers without affecting health or performance.


2020 ◽  
Vol 31 (2) ◽  
pp. 22-32
Author(s):  
Josephat S. Hema ◽  
Doreen A. Mloka ◽  
George M. Bwire ◽  
Ezekiel M. Marandu ◽  
Kennedy D. Mwambete

Background: The WHO estimates that approximately 600 million people fall ill after consumption of contaminated food and over 420 000 die every year, resulting in loss of 33 million healthy life years. Hand hygiene is considered by the WHO to be the most effective preventive measure for infectious diseases including food borne diseases.Methods: A laboratory-based study involving convenient sampling of common brands alcohol-based hand sanitizers (ABHS) from retail community pharmacies and local supermarkets was conducted in Ilala District, Dar es salaam, Tanzania. The study was conducted, between December 2018 to January 2019. A modified protocol of The European Norm (EN) 1500 was used for in vivo testing of sampled ABHs. Efficacy was evaluated using standard strain of Escherichia coli. A total of 26 healthy volunteers were used for hand sanitization. The percentage of bioburden/microbial reduction was assessed at baseline and after treatment, and the log reduction factor calculated.Results: A total of 10 gel ABHS were purchased and assayed for antibacterial efficacy. Majority (70%) of ABHS were imported products and contained ethanol as the sole active ingredient. About 60% of them did not correctly indicate the label disclosure information on concentration of active ingredients. Only one product was efficacious against E. coli with log reduction of 3.75; while majority (70%) of the samples had poor bacterial efficacy with log reduction ranging from 0.140 -0.664.Conclusions: Most of ABHS gel products available in the Dar es Salaam market were not efficacious as per FDA and EN 1500 guidelines. Post market surveillance is recommended of the circulating ABH to safe guard consumers. Keywords: Hand sanitizers, efficacy, E. coli, EN 1500.


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