动物双歧杆菌KDB19体内及体外安全性评价

安全性评价是益生菌应用的前提,动物双歧杆菌KDB19是一株潜在益生菌,本研究对该菌株进行体外及体内的安全性评价,为菌株应用提供基础保障。通过体外试验评价了KDB19的抗生素抗敏感性和生物胺的生成;体内试验评价了KDB19的经口毒性及易位风险。结果表明,菌株KDB19不存在菌株特有的抗生素敏感性,排除了抗生素抗性横向转移的风险;经过在脱羧酶培养基中培养未发现该菌株产生生物胺;灌胃试验发现,将该菌株分别以10~8cfu/鼠、10~9cfu/鼠、10~(10)cfu/鼠剂量饲喂小鼠28d后,小鼠未发生不良反应,在其血液、肾脏、肝脏未发现该菌株;研究未发现菌株KDB19的不安全因素。     

益生菌肠道黏附性研究进展

益生菌黏附于肠道上皮细胞是成功定植于宿主重要的一步,只有黏附于肠道上皮细胞才能发挥其益生性。文章主要介绍了细菌黏附机理,在体外利用不同的细胞模型研究不同细菌的黏附性,特别是乳酸菌对不同细胞的黏附性,以及目前细菌黏附的体外及体内检测方法。以期为益生菌的应用和有效性评价提供理论参考。     

副干酪乳杆菌L9安全性评价

本研究对益生菌菌株副干酪乳杆菌L9(Lactobacillus paracasei L9)进行了体外及体内的安全性评价。利用体外试验评价了L9的抗生素抗敏感性及生物胺的生成能力;体内试验评价了L9的经口毒性、正常状况下的易位风险及腹腔注射模拟的极端情况下的易位风险。结果表明,菌株L9不存在种属特有耐性以外的抗生素耐受性,不存在抗生素转移的风险;在脱羧酶培养基中培养未发现生物胺的产生;以108、109、1010 cfu/鼠灌胃28d,小鼠未发生不良反应,未发生向血液、肝脏、脾脏和肾脏的易位;109cfu/鼠腹腔注射发生易位现象,但未发生菌血症并且易位不会造成疾病或导致死亡,同时易位状况随时间有所缓解,表现为较高的易位安全性。试验结果证实副干酪乳杆菌L9具有较高安全性,可以直接应用于工业化生产。     

动物微生态制剂(益生菌)的标准、评价规程、功能和发展趋势

文章重点阐述了益生菌的概念、组成和特性及多种生物学功能;介绍了欧盟和FAO/WHO的益生菌选择标准和安全性评价规程,也阐述了作者对益生菌科学研究和产业发展趋势的观点。     

广西猪源益生菌的分离鉴定与生物学特性研究

为了解广西地区猪粪便与微生态发酵饲料中益生菌的存在情况及合理开发和利用猪源益生菌,本试验共采集了15份猪粪便样品和5份益生菌发酵饲料并对其进行益生菌的分离,研究益生菌的形态学特性、生理生化特性及16S rRNA分子序列,进行生长曲线、耐胆盐试验、温度敏感试验、模拟胃肠道耐受试验、耐药性试验、体外抑菌试验、小鼠安全性试验、体内/外抑菌试验,对分离菌株进行生物学特性的研究分析。结果显示,本试验共分离鉴定出6种、29株益生菌,分别为1株屎肠球菌（C2）、2株乳酸肠球菌（C1、C3）、3株植物乳杆菌（R20、R30、R37）、4株干酪乳杆菌（R41~R44）、7株枯草芽孢杆菌（K1~K7）和12株蜡样芽孢杆菌（Y1~Y12）。从中筛选出6株具有生长性能好、耐胆盐、耐高温、对胃肠道耐受、体外抑菌能力强的益生菌：乳酸肠球菌C1、屎肠球菌C2、植物乳杆菌R20、干酪乳杆菌R41、枯草芽孢杆菌K1和蜡样芽孢杆菌Y3。将筛选出的具有优良特性的菌株进行小鼠安全性试验,结果表明,在10⁹ CFU/mL浓度下灌胃6株益生菌对小鼠是安全无毒害的。与此同时,C2、R20、R41、Y3能极显著提高小鼠日增重（P<0.01）,K1能显著提高小鼠日增重（P<0.05）。体内抑菌试验结果表明,C2、R20、K1能降低沙门氏菌G21感染的小鼠的死亡率,有一定程度的体内抑菌作用。各项试验结果表明,R20和K1可作为猪源益生菌的选择菌株。     

抑制大肠杆菌K88的益生菌体外筛选

本研究以从断奶仔猪肠道分离的益生菌为试验菌株,将大肠杆菌K88和益生菌接种到体外培养的猪小肠上皮细胞(intestinal porcine epithelial cell-1,IPEC-1)中,测定培养2.5h上清液中的乳酸脱氢酶(lactate dehydrogenase,LDH)活性,同时将益生菌和大肠杆菌K88体外混合培养2.5h,进行平板计数,统计大肠杆菌K88菌数的变化,筛选出可以抑制大肠杆菌K88的益生菌。试验结果显示,干酪乳杆菌和凝结芽孢杆菌能显著降低IPEC-1培养上清液中的LDH活性(P<0.05),降低大肠杆菌K88对细胞的损伤;凝结芽孢杆菌能降低DMEM培养基中大肠杆菌K88的生长速度,结合模拟制粒过程及胃肠道环境的耐高温、耐酸及耐胆盐研究进行综合分析,该凝结芽胞杆菌对大肠杆菌K88有较好的抑制作用且具有良好的耐高温、耐酸及耐胆盐性能,具有作为微生态制剂菌株的应用潜力。本试验建立了能够抑制大肠杆菌K88的益生菌体外筛选技术模型。     

广西猪源益生菌的分离鉴定与生物学特性研究

为了解广西地区猪粪便与微生态发酵饲料中益生菌的存在情况及合理开发和利用猪源益生菌,本试验共采集了15份猪粪便样品和5份益生菌发酵饲料并对其进行益生菌的分离,研究益生菌的形态学特性、生理生化特性及16S rRNA分子序列,进行生长曲线、耐胆盐试验、温度敏感试验、模拟胃肠道耐受试验、耐药性试验、体外抑菌试验、小鼠安全性试验、体内/外抑菌试验,对分离菌株进行生物学特性的研究分析。结果显示,本试验共分离鉴定出6种、29株益生菌,分别为1株屎肠球菌(C2)、2株乳酸肠球菌(C1、C3)、3株植物乳杆菌(R20、R30、R37)、4株干酪乳杆菌(R41～R44)、7株枯草芽孢杆菌(K1～K7)和12株蜡样芽孢杆菌(Y1～Y12)。从中筛选出6株具有生长性能好、耐胆盐、耐高温、对胃肠道耐受、体外抑菌能力强的益生菌:乳酸肠球菌C1、屎肠球菌C2、植物乳杆菌R20、干酪乳杆菌R41、枯草芽孢杆菌K1和蜡样芽孢杆菌Y3。将筛选出的具有优良特性的菌株进行小鼠安全性试验,结果表明,在10~9 CFU/mL浓度下灌胃6株益生菌对小鼠是安全无毒害的。与此同时,C2、R20、R41、Y3能极显著提高小鼠日增重(P0.01),K1能显著提高小鼠日增重(P0.05)。体内抑菌试验结果表明,C2、R20、K1能降低沙门氏菌G21感染的小鼠的死亡率,有一定程度的体内抑菌作用。各项试验结果表明,R20和K1可作为猪源益生菌的选择菌株。     

抗菌肽在细菌感染动物模型中的抗菌活性和毒性评价方法研究进展

抗菌肽作为新型的潜在抗菌药物,在耐药问题日益严峻的今天引起了广泛关注。在对抗菌肽体外研究不断深入的同时,抗菌肽体内研究也逐渐成为关注重点。论文主要从抗菌肽的体内抗菌活性研究和毒性评价两个方面进行了综述,在体内抗菌活性研究中介绍了模型设计及动物试验原则、接种途径和模型鉴定方法,并对常用于抗菌肽体内研究的几种典型细菌感染动物模型建立及活性试验方法进行了总结,在毒性评价中主要介绍了测定半数致死量(LD50)法,同时对建模及活性毒性评价研究中的不同方法进行了对比分析。     

动物双歧杆菌A6体内外安全性评价

本研究对动物双歧杆菌A6进行了体外及体内的安全性评价,为菌株应用提供基础保障。通过体外试验评价了A6的抗生素敏感性和生物胺的生成;通过体内试验评价了A6的经口毒性及移位风险。试验结果表明,A6不存在菌株特有的抗生素敏感性,排除了抗生素耐性横向转移的风险;在脱羧酶培养基中培养,未发现该菌株产生生物胺;灌胃试验发现,将该菌株分别以2×10^8cfu/mL、2×10^9cfu/mL、2×10^10cfu/mL低中高三种剂量灌胃小鼠,每只小鼠每天灌胃0.2mL,连灌28d,结果小鼠无不良反应,在其血液、肾脏、肝脏未发现该菌株的移位现象。在对动物双歧杆菌A6安全性评价中,未发现菌株的不安全因素。     

南京市犬幽门螺杆菌感染的流行病学调查及其防治效果的研究

旨在调查南京市犬幽门螺杆菌(Hp)的感染率和特征,研究益生菌和抗生素在Hp治疗过程中的作用,评估Hp菌株的耐药情况。采用胶体金检测、PCR扩增和细菌分离纯化培养等方法鉴定Hp菌株,体内试验检测益生菌和抗生素的治疗效果,体外药敏试验评估菌株耐药性强弱。结果显示:南京市犬Hp总感染率为75.87%(393/518),不同生活环境下感染率为57.14%~80.65%;螺杆菌的感染率为87.10%(108/124),Hp占其中87.96%(95/108);此外,临床上采用抗生素辅以益生菌治疗能够明显提高Hp的消除率;Hp菌株对标准三联用药方案中的克拉霉素、阿莫西林耐药性增高。生活环境对犬的Hp感染有明显的影响,良好的生活饲养环境可有效降低犬的Hp感染率;临床抗生素治疗时辅以益生菌能够有效提升Hp的消除率,同时减少Hp菌株对其敏感抗生素耐药性的产生。     

Research Progress on the Evaluation Methods of Safety and Efficacy of Probiotics

Probiotics are live microorganisms. When they are administrated in adequate amounts, they can have beneficial effects on the host. They are widely applied in food fermentation and feed industry. With the appearance of commercial probiotics, more concerns are raised on the safety and efficacy evaluation of probiotics. At present, the evaluation of probiotics are mainly about the safety and efficacy, and both of them can be done in vivo and in vitro. When developing probiotic products, many companies rarely make a comprehensive safety evaluation of strains, and the evaluation index and methods used by various researchers from different countries are different. Besides, standards in efficacy evaluation of probiotics are not uniform either. In order to solve the problems of probiotics evaluation, it is necessary for evaluating the safety and effectiveness of the probiotics systematically and scientifically to establish a comprehensive evaluation method. From the aspects of potential harm and efficacy of probiotics, the authors summarizes recent developments in some aspects of safety evaluation in vitro including hemolytic, evaluation of virulence factors, antibiotic resistance and toxic metabolites-producing ability, in functional characteristics evaluation including resistance to acid and bile, tolerance to simulated gastrointestinal tract, adhesion capacity to gastrointestinal mucosa and epithelial cells, antimicrobial activity, and in safety and functional characteristics in vivo. The aim of this paper is to provide references to build a comprehensive technical system and standard of evaluation of probiotics.     

Study and use of the probiotic Lactobacillus reuteri in pigs:a review

Probiotics are living microorganisms that provide a wide variety of health benefits to the host when ingested in adequate amounts.The bacterial strains most frequently used as probiotic agents are lactic acid bacteria,such as Lactobacillus reuteri,which is one of the few endogenous Lactobacillus species found in the gastrointestinal tract of vertebrates,including humans,rats,pigs and chickens.L reuteri is one of the most well documented probiotic species and has been widely utilized as a probiotic in humans and animals for many years.Initially,L reuteri was used in humans to reduce the incidence and the severity of diarrhea,prevent colic and necrotic enterocolitis,and maintain a functional mucosal barrier.As interest in alternatives to in-feed antibiotics has grown in recent years,some evidence has emerged that probiotics may promote growth,improve the efficiency of feed utilization,prevent diarrhea,and regulate the immune system in pigs.In this review,the characteristics of L reuteri are described,in order to update the evidence on the efficacy of using L.reuteri in pigs.     

Probiotics--possibilities and limitations of their application in food, animal feed, and in pharmaceutical preparations for men and animals]

Probiotics are cultures of special microorganisms, which have been used as feed additives since the seventies of the past century and already since the twenties in food specimen and in pharmaceuticals. The definition of "Probioticum" was formulated in 1974 simultaneously with the use of living cultures in feed for various animals in order to substitute the application of nutritive antibiotics or chemotherapeutics. In the meantime probiotics are applied not only as feed supplements or pharmaceuticals but increasingly in suitable food specimens such as dairy products, fruit juices, chocolates, and even meat products. Of course, heating of such products prior to consumption or application must be ruled out. The selection of a suitable strain of a microorganism can be regarded as the primary requirement for the use as a probiotic. These cultures must be able to pass the stomach-duodenum barrier in a viable state and to multiply at the site of destination in the intestine. Additionally, they must be capable of producing antagonistic metabolites against a dominating saprophytic microflora resulting in a competitive growth. These abilities are common among lactic acid bacteria, e.g. lactobacilli and bifidobacteria. Yet, intended autochthonous species do not possess very good technological features for the enrichment in food specimens, because their viability will decrease rapidly under unfavourable conditions as it is the case with mineral supplements in feed or with low acidity in fermented dairy products. Therefore, some other microorganisms like spore-forming species or yeast cultures were introduced as probiotic components. These possess some similar features which render them suitable for probiotic use. But their physiological and ecological traits do not qualify them as probiotics of first choice. The special efficacy of probiotics must be strictly verified in animal nutrition due to restrictive EC-regulations, in pharmacy due to legal restraints, and in food applications in accordance with food law regulations. Safety aspects are considered very restrictively in feed applications, in the food and pharmaceutical sector they should be in accordance with the intended purpose of "fulfilling health claims". In the presented review the different requirements for the application of probiotics in animal nutrition, in food, and in pharmaceuticals will be provided. The special effect of competitive exclusion of pathogenetic and toxinogenic microorganisms in fowl performance are mentioned and even the application of probiotics as marine aquacultures of fish and Crustaceae will be included. Furthermore, the safety aspects resulting from the tremendous amount of industrially produced cultures which are distributed into the environment will be discussed. In conclusion it may be pointed out that probiotics may serve to partially replace the presently reduced or even prohibited application of nutritive antibiotics or chemotherapeutics in animal nutrition and in fulfillment of health claims in man and animals. Economic and environmental aspects will reduce the overall application of probiotics world-wide. Restrictions of use and controls of efficacy and safety are essential and must be implemented periodically.     

Probiotic Use in Horses – What is the Evidence for Their Clinical Efficacy?

The gastrointestinal microbiota is extremely important for human and animal health. Investigations into the composition of the microbiota and its therapeutic modification have received increasing interest in human and veterinary medicine. Probiotics are a way of modifying the microbiota and have been tested to prevent and treat diseases. Probiotics are proposed to exert their beneficial effects through various pathways. Production of antimicrobial compounds targeting intestinal pathogens, general immune stimulation, and colonization resistance are among these mechanisms. Despite widespread availability and use, scientific, peer‐reviewed evidence behind commercial probiotic formulations in horses is limited. Additionally, quality control of commercial over‐the‐counter products is not tightly regulated. Although promising in vitro results have been achieved, in vivo health benefits have been more difficult to prove. Whether the ambiguous results are caused by strain selection, dosage selection or true lack of efficacy remains to be answered. Although these limitations exist, probiotics are increasingly used because of their lack of severe adverse effects, ease of administration, and low cost. This review summarizes the current evidence for probiotic use in equine medicine. It aims to provide veterinarians with evidence‐based information on when and why probiotics are indicated for prevention or treatment of gastrointestinal disease in horses. The review also outlines the current state of knowledge on the equine microbiota and the potential of fecal microbial transplantation, as they relate to the topic of probiotics.     

Study and use of the probiotic Lactobacillus reuteri in pigs: a review

Probiotics are living microorganisms that provide a wide variety of health benefits to the host when ingested in adequate amounts. The bacterial strains most frequently used as probiotic agents are lactic acid bacteria, such as Lactobacillus reuteri, which is one of the few endogenous Lactobacillus species found in the gastrointestinal tract of vertebrates, including humans, rats, pigs and chickens. L. reuteri is one of the most well documented probiotic species and has been widely utilized as a probiotic in humans and animals for many years. Initially, L. reuteri was used in humans to reduce the incidence and the severity of diarrhea, prevent colic and necrotic enterocolitis, and maintain a functional mucosal barrier. As interest in alternatives to in-feed antibiotics has grown in recent years, some evidence has emerged that probiotics may promote growth, improve the efficiency of feed utilization, prevent diarrhea, and regulate the immune system in pigs. In this review, the characteristics of L. reuteri are described, in order to update the evidence on the efficacy of using L. reuteri in pigs.     

益生菌与功能发酵乳开发研究进展

近10 年来，随着先进研究方法的使用和研究内容的不断深入，对益生菌的认识取得重大进展，尤其是对益生菌促进健康作用的机理逐渐清晰，益生菌制备技术和产业化技术更加成熟，为新型发酵乳的开发提供了坚实的发展基础。本文对益生菌功能机理、遗传转化及代谢调控的研究现状和发展进行阐述，介绍分离自内蒙古马乳酒中的干酪乳杆菌LC2W和分离自发酵蔬菜中的植物乳杆菌ST-Ⅲ的益生特性、基因组及产胞外多糖特性，并进一步探讨基于植物乳杆菌增殖技术开发含高活菌数的纯植物乳杆菌发酵乳品，以期为益生菌和功能发酵乳的应用开发提供理论依据。发酵乳品是益生菌的良好载体，吸收现代益生菌科技成果，加强循证医学方法论证，基于生物活性效应分子及生物活性评价，增加临床研究数据，新型发酵乳将为人类健康做出更多贡献。     

Probiotics in animal nutrition: a review

The normal microflora colonizing the digestive tract in livestock species at five to six days after birth can be summarized as following: 400 to 500 different bacterial strains for a total count of 10(14) bacteriae. The role of the gut flora is multifarious: fermentation of feed compounds, induction of anatomical and physiological changes in the intestinal cell wall structure, increase in animal resistance against enteropathogenic bacteriae, etc. In the present review, the numerous hypotheses for explaining the beneficial effects of probiotics on zootechnical performances and also the healthy aspects for men and animals are summarized, and the possible mechanisms of bacterial attachment are enumerated. The different assumptions on mode of action and fixation mechanisms of probiotics in the gut are critically discussed, and the required characteristics of the ideal probiotic are listed. Finally, some zootechnical results obtained with lactic acid bacteria are shown for calves, piglets and broilers.     

Putative probiotic Lactobacillus spp. from porcine gastrointestinal tract inhibit transmissible gastroenteritis coronavirus and enteric bacterial pathogens

A total of 310 bacterial strains isolated from the porcine gastrointestinal tract were tested for their activity against transmissible gastroenteritis (TGE) coronavirus and other enteric pathogens. Based on activity, the strains Probio-38 and Probio-37 were selected as potential probiotics and identified as Lactobacillus plantarum Probio-38 and Lactobacillus salivarius Probio-37 respectively by 16S rRNA gene sequencing. Supernatants of these strains inhibited TGE coronavirus in vitro in ST cells, without any cytopathic effect even after 72 h of incubation. Both the strains exhibited high survival in synthetic gastric juice. The strains were resistant to 5% porcine bile and exhibited antimicrobial activity against all the 13 enteric bacterial pathogens tested. These strains also exhibited resistance to most of the antibiotics analyzed. The inhibition of transmissible gastroenteritis coronavirus and enteric bacterial pathogens as well as the bile tolerance, high survival in gastric juice, and the antibiotic resistance indicate that the two isolated bacterial strains are ideal probiotic candidates for animal application after proper in vivo experiments.     

益生菌健康宣称的调研分析

我国市场上将益生菌进行健康宣称的食品主要涉及调制乳粉、酸乳、乳酸菌饮料和益生菌粉。本次调研主要从产品中添加益生菌的种类、产品包装正面益生菌的健康宣称和产品包装背面益生菌的健康宣称三方面进行。同时对比我国与国外益生菌健康宣称的法规,针对国内益生菌健康宣称管理中的问题提出相关建议。结果表明：不同产品的益生菌添加种类不同,调制乳粉中添加的益生菌一般为1～2 种,而乳酸菌饮料、酸乳和益生菌粉中添加的益生菌大多在2 种以上,有些产品达到10 种以上;益生菌产品包装正面用语主要涉及“益生菌”、“活性”、“菌株名称”、