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Animal Nutrition 2023年第2期13卷 78-89页

作者： Shuo Yang Xiaoqing Xu Qing Peng Lan Ma Yu Qiao Bo Shi Feed Research Institute Chinese Academy of Agricultural SciencesBeijing100081China

Over-use or misuse of antibiotics in livestock and poultry production contributes to the rising threat of antibiotic resistance in animals and has negative ecological *** from lactic acid bacteria(LAB-EPS)are a class of biological macromolecules which are secreted by lactic acid bacteria to the outside of the cell wall during their growth and *** studies demonstrated that LAB-EPS have anti-inflammatory and antimicrobial activities and are able to regulate intestinal health and the immune system in *** are biodegradable,nontoxic and bio-compatible,which are considered as ideal alternatives to *** review aims to discuss and summarize recent research findings of LAB-EPS on regulation of intestinal health and the immune system in animals,and thus provide scientific justification for commercial applications of LAB-EPS in livestock.

关键词： Lactic acid bacteria exopolysaccharides Intestinal health Immune function

exopolysaccharides of Lactobacillus rhamnosus GG ameliorate Salmonella typhimurium-induced intestinal inflammation via the TLR4/NF-κB/MAPK pathway

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1501-1513页

作者： Jinze Li Qiuke Li Qianhui Wu Nan Gao Zhihua Wang Yang Yang Anshan Shan Institute of Animal Nutrition Northeast Agricultural UniversityHarbin 150030P.R.China

Background Salmonella typhimurium(S.T),as an important foodborne bacterial pathogen,can cause diarrhea and gastroenteritis in humans and *** studies have confirmed that exopolysaccharides(EPSs)have various biological functions,but the mechanism through which EPSs improve the immunity of animals against the invasion of pathogenic bacteria is ***,we explored the protective effect of EPSs of Lactobacillus rhamnosus GG(LGG)on the S.T-infected *** Mice received adequate food and drinking water for one week before the start of the *** 7 d of prefeeding,2×108 CFU/mL S.T solution and an equivalent volume of saline(control group)were given orally for 1 *** the fourth day,the mice were treated with 0.5 mg/mL EPSs,1.0 mg/mL EPSs,2.0 mg/mL EPSs,or 2.0 mg/mL penicillin for 7 ***,the body and relative organ weight,histological staining,and the levels of antioxidant enzyme activity and inflammatory cytokines were *** The S.T-infected mice exhibited symptoms of decreased appetite,somnolence,diarrhea and flagging *** with EPSs and penicillin improved the weight loss of the mice,and the high dose of EPSs showed the best therapeutic *** significantly ameliorated S.T-induced ileal injury in ***-dose EPSs were more effective than penicillin for alleviating ileal oxidative damage induced by *** mRNA levels of inflammatory cytokines in the ileum of mice showed that the regulatory effects of EPSs on inflammatory cytokines were better than those of *** could inhibit the expression and activation of key proteins of the TLR4/NF-κB/MAPK pathway and thereby suppress the level of S.T-induced ileal *** EPSs attenuate S.T-induced immune responses by inhibiting the expression of key proteins in the TLR4/NF-κB/MAPK signaling ***,EPSs could promote bacterial aggregation into clusters,which may be a potential strategy for reducing the bacterial invasion of

关键词： exopolysaccharides Lactobacillus rhamnosus Salmonella typhimurium TLR4/NF-κB/MAPK

Identification of Anamorph Yeast of Tremella aurantialba and Optimization of Medium Composition for Production of exopolysaccharides

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过程工程学报 2012年第6期12卷 973-981页

作者：刘春卉杨秀伟俞建国马维新瞿伟菁包艳洁武文斌庄秀园 China National Institute of Standardization Beijing 100088China Dept.Natural Medicines State Key Lab.Natural and Biomimetic DrugsSch.Pharm.Sci.Peking Univ.Beijing 100191China Jiangsu Tongyuantang Bio-engineering Co. Ltd.TaixingJiangsu 225400China School of Life Science East China Normal UniversityShanghai 200062China

A yeast-like fungus strain B1 isolated from wild fungus Tremella aurantialba was identified and initially characterized. Two phylogenetic trees were generated based on the sequences of large subunit ribosomal RNA gene D1/D2 regions and internal transcribed spacer (ITS) regions of related fungi, respectively. The analysis of D1/D2 regions and ITS sequences showed that fungus B1 was clustered together with T. aurantialba, T. aurantia and T. microspore in the phylogenetic trees. Both the morphological characteristic and phylogenetic analysis established that fungus B1 was one of the anamorph strains of T. aurantialba and belongs to Tremella genus. A fermentation medium for exopolysaccharides (EPS) production by T. aurantialba B1 . Plackett-Burmen design was used to evaluate the effects of different components in the culture medium. Glucose and yeast extract have significant influence on the EPS production. The concentrations of two factors were optimized subsequently using central composite design and response surface analysis. The results showed that 49.2 g/L glucose and 10.4 g/L yeast extract could lead to the maximum production of EPS (4.99 g/L). The optimized medium led to a 1.5-fold enhancement of the production of EPS by T. aurantialba B1 , as compared with that without optimization.

关键词： Tremella aurantialba anamorph yeast large subunit ribosomal RNA gene internal transcribed spacer exopolysaccharides central composite design

Antioxidant Activities of exopolysaccharides Produced by Lactic Acid Bacteria Isolated from Commercial Yoghurt Samples

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Advances in Microbiology 2020年第8期10卷 359-374页

作者： Aminat O. Adelekan Taiwo O. Olurin Abiola O. Ezeani Department of Chemical and Food Sciences Bells University of Technology Ota Nigeria

An antioxidant is a substance that inhibits the oxidation of other molecules caused by free radicals. The inbuilt antioxidant systems possessed by living organisms are generally not enough to prevent them from oxidative damages and the uses of synthetic antioxidants also have some harmful effects. This study was aimed at evaluating the antioxidant activities of exopolysaccharides produced by lactic acid bacteria isolated from yoghurt. Lactic acid bacteria (LAB) were isolated from six different brands of commercially available yoghurt using deMan Rogosa Sharpe (MRS) agar. The LAB isolates were identified based on morphological and biochemical analyses and were screened for exopolysaccharide (EPS) production. The LAB isolates screened positive were used for EPS production in a liquid medium and the EPS produced were purified and quantified using standard methods. Antioxidant activities of the EPS were evaluated by determining the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric ion reducing power, and total phenolic contents. Data obtained were analysed using Analysis of Variance. Total lactic acid bacterial count obtained from the yoghurt samples ranged from 0 - 3.9 × 104

关键词： Antioxidant Activities exopolysaccharides Lactic Acid Bacteria Commercial Yoghurt

Effect of arsenic on tolerance mechanisms of two plant growth-promoting bacteria used as biological inoculants

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Journal of Environmental Sciences 2015年第7期27卷 203-210页

作者： Ana L.Armendariz Melina A.Talano Ana L.Wevar Oller María I.Medina Elizabeth Agostini Departamento de Biología Molecular FCEFQy N Universidad Nacional de Río Cuarto

Bacterial ability to colonize the rhizosphere of plants in arsenic（As） contaminated soils is highly important for symbiotic and free-living plant growth-promoting rhizobacteria（PGPR）used as inoculants, since they can contribute to enhance plant As tolerance and limit metalloid uptake by plants. The aim of this work was to study the effect of As on growth,exopolysaccharide（EPS） production, biofilm formation and motility of two strains used as soybean inoculants, Bradyrhizobium japonicum E109 and Azospirillum brasilense Az39. The metabolism of arsenate（As（V）） and arsenite（As（III）） and their removal and/or possible accumulation were also evaluated. The behavior of both bacteria under As treatment was compared and discussed in relation to their potential for colonizing plant rhizosphere with high content of the metalloid. B. japonicum E109 growth was reduced with As（III）concentration from 10 μM while A. brasilense Az39 showed a reduction of growth with As（III） from 500 μM. EPS and biofilm production increased significantly under 25 μM As（III）for both strains. Moreover, this was more notorious for Azospirillum under 500 μM As（III）,where motility was seriously affected. Both bacterial strains showed a similar ability to reduce As（V）. However, Azospirillum was able to oxidize more As（III）（around 53%） than Bradyrhizobium（17%）. In addition, both strains accumulated As in cell biomass. The behavior of Azospirillum under As treatments suggests that this strain would be able to colonize efficiently As contaminated soils. In this way, inoculation with A. brasilense Az39 would positively contribute to promoting growth of different plant species under As treatment.

关键词： Accumulation Arsenic Biofilm Colonization exopolysaccharides Plant growth-promoting rhizobacteria

Silver nanoparticles tolerant bacteria from sewage environment

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Journal of Environmental Sciences 2011年第2期23卷 346-352页

作者： Sudheer Khan Amitava Mukherjee Natarajan Chandrasekaran Nanobio-Medicine Laboratory School of Bio-Sciences and TechnologyVIT University

Silver nanoparticle （SNP） is a threat to soil, water and human health. Protection of environment from silver nanoparticles is a major concern. A sewage isolate, Bacillus pumilus treated with SNPs showed similar growth kinetics to that without nanoparticles. A reduction in the amount of exopolysaccharides was observed after SNPs - B. pumilus culture supernatant interaction. The Fourier transform infrared spectroscopy （FT-IR） peaks for the exopolysaccharides extracted from the bacterial culture supernatant and＇the interacted SNPs were almost similar. The exopolysaccharide capping of the SNPs was confirmed by UV-Visible, FT-IR and X-ray diffraction analysis. The study of bacterial exopolysaccharides capped SNPs with E. coli, S. aureus and M. luteus showed less toxicity compared to uncoated SNPs. Our studies suggested that the capping of nanopartieles by bacterially produced exopolysaccharides serve as the probable mechanism of tolerance.

关键词： Bacillus pumilus silver nanoparticles exopolysaccharides encapsulation bacterial tolerance toxicity reduction

Biofilm three-dimensional architecture influences in situ pH distribution pattern on the human enamel surface

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International Journal of Oral Science 2017年第2期9卷 74-79页

作者： Jin Xiao Anderson T Hara Dongyeop Kim Domenick T Zero Hyun Koo Geelsu Hwang Eastman Institute for Oral Health University of Rochester Medical Center Department of Cariology Operative Dentistry and Dental Public HealthOral Health Research InstituteIndiana University School of Dentistry Biofilm Research Laboratories Levy Center for Oral HealthDepartment of Orthodontics and Divisions of Pediatric Dentistry & Community Oral HealthSchool of Dental MedicineUniversity of Pennsylvania

To investigate how the biofilm three-dimensional(3D) architecture influences in situ pH distribution patterns on the enamel surface. Biofilms were formed on human tooth enamel in the presence of 1% sucrose or 0.5% glucose plus 0.5% fructose. At specific time points, biofilms were exposed to a neutral pH buffer to mimic the buffering of saliva and subsequently pulsed with 1% glucose to induce re-acidification. Simultaneous 3D pH mapping and architecture of intact biofilms was performed using two-photon confocal microscopy. The enamel surface and mineral content characteristics were examined successively via optical profilometry and microradiography analyses. Sucrose-mediated biofilm formation created spatial heterogeneities manifested by complex networks of bacterial clusters(microcolonies). Acidic regions(pH<5.5) were found only in the interior of microcolonies,which impedes rapid neutralization(taking more than 120 min for neutralization). Glucose exposure rapidly re-created the acidic niches, indicating formation of diffusion barriers associated with microcolonies structure. Enamel demineralization(white spots),rougher surface, deeper lesion and more mineral loss appeared to be associated with the localization of these bacterial clusters at the biofilm-enamel interface. Similar 3D architecture was observed in plaque-biofilms formed in vivo in the presence of sucrose. The formation of complex 3D architectures creates spatially heterogeneous acidic microenvironments in close proximity of enamel surface, which might correlate with the localized pattern of the onset of carious lesions(white spot like) on teeth.

关键词： biofilms demineralization dental caries exopolysaccharides microcolonies pH microenvironments plaque Streptococcus mutans

Modulating of food glycemic response by lactic acid bacteria

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Food Bioscience 2022年第3期47卷 1090-1097页

作者： Ceren Mutlu Cihadiye Candal-Uslu Hazal Özhanlı Sultan Arslan-Tontul Mustafa Erbas Department of Food Engineering Engineering FacultyAkdeniz University07058AntalyaTurkey Department of Food Engineering Engineering FacultyBalikesir University10145BalikesirTurkey Faculty of Health Science Nutrition and DieteticsArtvin Coruh University08100ArtvinTurkey Department of Food Engineering Agricultural FacultySelcuk University42130KonyaTurkey

There are some strategies for modulating the glycemic response of food through synthesized metabolites such as organic acids,fatty acids,sugar alcohols,bioactive peptides,and exopolysaccharides by bacteria,yeast,and/or fungi during *** different species of lactic acid bacteria (LAB) are the most important option in fermented food production because they are considered food-grade,their products can be directly used in food,their usability of a cheap and wide range of substrate,and suitable for genetic *** can contribute to lowering the glycemic load of nutrition through their organic acid,alcohol,polysaccharides,and vitamin *** study aimed to review the effects of lowering the glycemic responses of foods by LAB via metabolites produced and their contribution to human well-being in this way.

关键词： Lactic acid bacteria Starch digestibility exopolysaccharides Sugar alcohol Glycemic index Diabetes

Recent biotechnological trends in lactic acid bacterial fermentation for food processing industries

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Systems Microbiology and Biomanufacturing 2022年第1期2卷 14-40页

作者： Tirath Raj K.Chandrasekhar A.Naresh Kumar Sang-Hyoun Kim School of Civil and Environmental Engineering Yonsei UniversitySeoul 03722Republic of Korea

Lactic acid bacteria(LAB)are non-mobile,gram-positive,non-spore-forming,micro-aerophilic microorganisms widely explored as starter cultures food industry to enhance the gustatory,nutritional value,imparts appetizing favour,texture to milk,vegetative,meat foods and prolongs their shelf *** vast review emphasis various LABs widely explored in the food ***,we have summarized the classifcation of LAB strains,their metabolic pathways for biosynthesis of lactic acid,ethanol,acetic acid and demonstrated their application in various food industries for making fermented milk(yoghurt),cheese,beverages,bread,and animal *** wide spectrum of LAB-based probiotics,bacteriocins,exopolysaccharides,bio preservative and their relevant benefts towards human health has also been ***,LAB bacteriocins and probiotics in food application may limit the growth of pathogenic,while boosting health *** exopolysaccharides have interesting characteristics for the fermented food industry as new functional *** on,we have discussed the various advancement in metabolic engineering,synthetic biology tools,which have gained considerable interest to elucidate the biosynthetic pathway for tailoring cellular metabolism for high activity.

关键词： Lactic acid bacteria Fermentation exopolysaccharides Carbohydrates Bacteriocins Probiotics

Azospirillum brasilense and Saccharomyces cerevisiae as Alternative for Decrease the Effect of Salinity Stress in Tomato(Lycopersicon esculentum)Growth

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Phyton-International Journal of Experimental Botany 2022年第1期91卷 21-32页

作者： Ali Abdelmoteleb Daniel Gonzalez-Mendoza Ahmed Mohamed Elbaalawy Botany Department Faculty of AgricultureMenoufia UniversityShebin El-KomPo 32511Egypt Instituto de Ciencias Agrícolas Universidad Autónoma de Baja CaliforniaCarretera a Delta s/n Ejido Nuevo LeónBaja CaliforniaCP 21705México Department of Soil Science Faculty of AgricultureMenoufia UniversityShebin El-KomPo 32511Egypt

The salinity stress is one of the most relevant abiotic stresses that affects the agricultural *** present study was performed to study the improvement of the salt tolerance of tomato plants which is known for their susceptibility to salt *** present study aimed to assess to what extent strain Azospirillum brasilense(N040)and Saccharomyces cerevisiae improve the salt tolerance to tomato plants treated with different salt *** inoculant strain ***(N040)was previously adapted to survive up to 7%NaCl in the basal media.A greenhouse experiment was conducted to evaluate the effect of this inoculation on growth parameter such as:plant height,root length,fresh and dry weight,fruits fresh weight,chlorophyll content,proline and total soluble sugar in tomato plants under salt stress *** results revealed that co-inoculation of Azospirillum brasilense(N040)and Saccharomyces cerevisiae significantly increased the level of proline(8.63 mg/g FW)and total soluble sugar(120 mg/g FW)of leaves under salinity condition comparing to non-inoculated plants(2.3 mg/g FW and 70 mg/g FW,respectively).Plants co-inoculated with adapted strain of *** and *** showed the highest significant(p<0.01)increase in fruit yield(1166.6 g/plant),plant high(115 cm)and roots length(52.6)compared whit un-inoculated control plants(42 g/pant,43.3 cm and 29.6 cm,respectively).In contrast,Na^(+)ion content was significantly decreased in the leaves of salt stressed plants treated with the ***(N040)and ***,the results showed that dual benefits provided by both ***(N040)and *** can provide a major way to improve tomato yields in saline soils.

关键词： Salinity stress tomato proline exopolysaccharides microorganism