Prevention of infections by probiotics

'Viable bacteria that exhibit beneficial effects for health based on improvement of balance of intestinal bacterial flora' was the most common definition of probiotics, but the diversity of their action mechanisms, including immune regulation, has been clarified, and probiotics have recently been broadly defined as 'live microorganisms which when administered in adequet amounts confer a health benefit on the host'. Coined words such as prebiotics, describing non-digestible food fiber components that contribute to host health by activating proliferation and function of beneficial intestinal bacteria, and synbiotics, describing a combination of probiotics and prebiotics have also been established as medical expressions. In this report, clinical studies of probiotics, prebiotics, and synbiotics on prevention of infection by various infectious diseases in humans are reviewed. The effects of and action mechanisms against sporadic intestinal infectious diseases that are difficult to investigate in humans (enterohemorrhagic Escherichia coli and Salmonellosis) in experimental animal models are also reviewed. Finally, points necessary for clarification of the role of probiotics in health care, and their functions in health care foods are discussed.     

Evolutionary concepts in the functional biotics arena: a mini-review

Over the years, the attempts to elucidate the role of beneficial microorganisms in shaping human health are becoming fairly apparent. The functional impact conferred by such microbes is not only transmitted by viable cells or their metabolites but also through non-viable cells. Extensive research to unveil the protective action of such wonder bugs has resulted in categorizing the beneficial microflora and their bioactive metabolites into a variety of functional biotic concepts based on their intended applications in various forms. In the modern era, these are often termed as probiotics, prebiotics, synbiotics, postbiotics, next-generation probiotics, psychobiotics, oncobiotics, pharmabiotics, and metabiotics. Currently, the concept of traditional probiotics is being widened to include microbes beyond lactic acid bacteria. Indeed, this diversification has broadened the functional food portfolio from food to pharmaceuticals. In this context, the present review aims to summarize the existing biotic concepts and their differences thereof.     

Prebiotics as functional foods: A review

Prebiotics are short chain carbohydrates that are non-digestible by digestive enzymes in humans and selectively enhance the activity of some groups of beneficial bacteria. In the intestine, prebiotics are fermented by beneficial bacteria to produce short chain fatty acids. Prebiotics also render many other health benefits in the large intestine such as reduction of cancer risk and increase calcium and magnesium absorption. Prebiotics are found in several vegetables and fruits and are considered functional food components which present significant technological advantages. Their addition improves sensory characteristics such as taste and texture, and enhances the stability of foams, emulsions and mouthfeel in a large range of food applications like dairy products and bread. This contribution reviews bioactives from food sources with prebiotic properties. Additionally, food application of bioactive prebiotics, stimulation of the viability of probiotics, health benefits, epidemiological studies, and safety concerns of prebiotics are also reviewed.     

Effectiveness of probiotics,prebiotics, and prebiotic‐like components in common functional foods

The bioactive ingredients in commonly consumed foods include, but are not limited to, prebiotics, prebiotic‐like components, probiotics, and postbiotics. The bioactive ingredients in functional foods have also been associated with beneficial effects on human health. For example, they aid in shaping of gut microflora and promotion of immunity. These functional components also contribute in preventing serious diseases such as cardiovascular malfunction and tumorigenesis. However, the specific mechanisms of these positive influences on human health are still under investigation. In this review, we aim to emphasize the major contents of probiotics, prebiotics, and prebiotic‐like components commonly found in consumable functional foods, and we present an overview of direct and indirect benefits they provide on human health. The major contributors are certain families of metabolites, specifically short‐chain fatty acids and polyunsaturated fatty acids produced by probiotics, and prebiotics, or prebiotic‐like components such as flavonoids, polyphenols, and vitamins that are found in functional foods. These functional ingredients in foods influence the gut microbiota by stimulating the growth of beneficial microbes and the production of beneficial metabolites that, in turn, have direct benefits to the host, while also providing protection from pathogens and maintaining a balanced gut ecosystem. The complex interactions that arise among functional food ingredients, human physiology, the gut microbiota, and their respective metabolic pathways have been found to minimize several factors that contribute to the incidence of chronic disease, such as inflammation oxidative stress.     

功能性益生菌的筛选及在食品中应用进展

益生菌是指能够促进宿主健康,对机体有益的一类活性微生物。目前存在的益生菌一类是动物体内本身就存在的,另一类是从发酵食品和自然界中筛选的有益于人体健康的菌种。因益生菌可以通过抑制肠道病原菌、降血脂血糖血压、增强机体免疫力、抗氧化等不同的途径对人体机体有益,从而在世界各地不断的有新的益生菌被筛选出来和进行开发应用。该文通过综述益生菌的定义、种类、功能;益生菌的筛选标准;不同益生菌的筛选途径、功能性益生菌在食品中的开发应用和发展趋势,以期为功能性益生菌的进一步研究开发提供理论借鉴。     

乳酸菌代谢低聚果糖/菊粉途径及机理的研究进展

合生元又称合生素,指益生元与益生菌结合使用的生物制剂（微生态制剂）,近年来,越来越多研究表明合生元具有多种益处,益生元和益生菌的选择对其最终效果起着至关重要的作用。低聚果糖和菊粉是合生元中常见的益生元,可被肠道内的乳酸菌选择性吸收,通过促进益生菌增殖的方式来改善机体健康。本文综述了乳酸菌对低聚果糖和菊粉的代谢差异及代谢途径,并从分子水平阐述水解酶、转运系统、调控蛋白的作用机制,以期为探明乳酸菌调控低聚果糖和菊粉的代谢网络提供依据;同时总结了近年来低聚果糖/菊粉合生元的应用,为益生元与益生菌的进一步联用提供参考。     

Probiotics and prebiotics--perspectives and challenges

Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.     

益生菌、益生元的研究发展新动向

人们已确定的知道人体的结肠微生物区对健康有着极大的影响.自从引入益生菌和益生元的概念后,关于人体肠微生物区组成的观点产生了极大的变化.对于科学家特别是细菌学家来讲,详细研究复杂的细菌群落一直是个巨大的挑战.预期用抽样法研究肠微生物群将会更加成熟并广泛应用于此项研究.以核酸为基础的分析方法目前是研究肠微生物区系的基本工具.应用先进的分子技术,使点查和鉴定结肠细菌的种类以及族系级别成为可能.目前正在对第二代益生元的概念展开广泛研究.了解内脏生态系统的作用机制以及处于内脏生态系统中的细菌的作用机制对于益生菌和益生元将来的发展极为重要.     

Functional cultures and health benefits

A number of health benefits have been claimed for probiotic bacteria such as Lactobacillus acidophilus, Bifidobacterium spp., and L. casei. These benefits include antimutagenic effects, anticarcinogenic properties, improvement in lactose metabolism, reduction in serum cholesterol, and immune system stimulation. Because of the potential health benefits, these organisms are increasingly being incorporated into dairy foods, particularly yoghurt. In addition to yoghurt, fermented functional foods with health benefits based on bioactive peptides released by probiotic organisms, including Evolus^® and Calpis^®, have been introduced in the market. To maximize effectiveness of bifidus products, prebiotics are used in probiotic foods. Synbiotics are products that contain both prebiotics and probiotics.     

Review Article: Technological Aspects of Prebiotics in Probiotic Fermented Milks

Prebiotics are food components that exert beneficial effects on health of the host, associated with modulation of the intestinal flora via stimulating the growth and/or activity of the probiotics. One of the recommended ways to maintain high viable numbers of probiotic bacteria in the intestine as well as in the probiotic fermented milk products until the time of consumption is via the use of prebiotics. These compounds can also affect sensory profile, physicochemical and rheological characteristics, and economic properties of probiotic fermented milk products. In this article, technological aspects of prebiotics (viability of probiotics in the product as well as the physicochemical, rheological, sensory, and economic characteristics of product) in probiotic fermented milks are reviewed.     

Probiotics,prebiotics, and microencapsulation: A review

The development of a suitable technology for the production of probiotics is a key research for industrial production, which should take into account the viability and the stability of the organisms involved. Microbial criteria, stress tolerance during processing, and storage of the product constitute the basis for the production of probiotics. Generally, the bacteria belonging to the genera Lactobacillus and Bifidobacterium have been used as probiotics. Based on their positive qualities, probiotic bacteria are widely used in the production of food. Interest in the incorporation of the probiotic bacteria into other products apart from dairy products has been increasing and represents a great challenge. The recognition of dose delivery systems for probiotic bacteria has also resulted in research efforts aimed at developing probiotic food outside the dairy sector. Producing probiotic juices has been considered more in the recent years, due to an increased concern in personal health of consumers. This review focuses on probiotics, prebiotics, and the microencapsulation of living cells.     

Influence of functional food components on gut health

Intestinal epithelial cells (IECs) lining the gastrointestinal tract establish a barrier between external environments and the internal milieu. An intact intestinal barrier maintains gut health and overall good health of the body by preventing from tissue injury, pathogen infection and disease development. When the intestinal barrier function is compromised, bacterial translocation can occur. Our gut microbiota also plays a fundamentally important role in health, for example, by maintaining intestinal barrier integrity, metabolism and modulating the immune system, etc. Any disruption of gut microbiota composition (also termed dysbiosis) can lead to various pathological conditions. In short, intestinal barrier and gut microbiota are two crucial factors affecting gut health. The gastrointestinal tract is a complex environment exposed to many dietary components and commensal bacteria. Dietary components are increasingly recognized to play various beneficial roles beyond basic nutrition, resulting in the development of the functional food concepts. Various dietary modifiers, including the consumption of live bacteria (probiotics) and ingestible food constituents such as prebiotics, as well as polyphenols or synbiotics (combinations of probiotics and prebiotics) are the most well characterized dietary bioactive compounds and have been demonstrated to beneficially impact the gut health and the overall well-being of the host. In this review we depict the roles of intestinal epithelium and gut microbiota in mucosal defence responses and the influence of certain functional food components on the modulation of gut health, with a particular focus on probiotics, prebiotics and polyphenols.     

Modulation of Intestinal Epithelial Defense Responses by Probiotic Bacteria

Probiotics are live microorganisms, which when administered in food confer numerous health benefits. In previous studies about beneficial effects of probiotic bacteria to health, particularly in the fields of intestinal mucosa defense responses, specific probiotics, in a strain-dependent manner, show certain degree of potential to reinforce the integrity of intestinal epithelium and/or regulate some immune components. The mechanism of probiotic action is an area of interest. Among all possible routes of modulation by probiotics of intestinal epithelial cell-mediated defense responses, modulations of intestinal barrier function, innate, and adaptive mucosal immune responses, as well as signaling pathways are considered to play important role in the intestinal defense responses against pathogenic bacteria. This review summarizes the beneficial effects of probiotic bacteria to intestinal health together with the mechanisms affected by probiotic bacteria: barrier function, innate, and adaptive defense responses such as secretion of mucins, defensins, trefoil factors, immunoglobulin A (IgA), Toll-like receptors (TLRs), cytokines, gut associated lymphoid tissues, and signaling pathways.     

Effect of Different Aloe Fractions on the Growth of Lactic Acid Bacteria

Several foods on the market, such as yogurt and fermented milk, include mixtures of prebiotics and probiotic microorganisms effective in promoting the proliferation and equilibrium of intestinal bacteria, thus improving gut health. Particularly, researchers and the public have shown increasing interest in the combination of probiotics with natural substances that promote health or that can act as substrates to promote bacterial growth. The aim of this study is to evaluate the effects of different extracts of Aloe barbadensis and Aloe arborescens in fermented milk, taking into account both the prebiotic effect of aloe polysaccharides and the antimicrobial activity of several secondary metabolites. The results demonstrate a beneficial effect of 5% aloe inner gel on Lactobacillus growth and confirm the antimicrobial activity of the phenolic compounds peculiar of green rind extracts.     

Potential interactions among phenolic compounds and probiotics for mutual boosting of their health-promoting properties and food functionalities – A review

Several foods are rich sources of phenolic compounds (PC) and their beneficial effects on human health may be increased through the action of probiotics. Additionally, probiotics may use PC as substrates, increasing their survival and functionality. This review presents available studies on the effects of PC on probiotics, including their physiological functionalities, interactions and capability of surviving during exposure to gastrointestinal conditions and when incorporated into food matrices. Studies have shown that PC can improve the adhesion capacity and survival of probiotics during exposure to conditions that mimic the gastrointestinal tract. There is strong evidence that PC can modulate the composition of the gut microbiota in hosts, improving a variety of biochemical markers and risk factors for chronic diseases. Available literature also indicates that metabolites of PC formed by intestinal microorganisms, including probiotics, exert a variety of benefits on host health. These metabolites are typically more active than parental dietary PC. The presence of PC commonly enhances probiotic survival in different foods. Finally, further clinical studies need to be developed to confirm in vitro and experimental findings concerning the beneficial interactions among different PC and probiotics.     

婴幼儿用益生菌的研究现状及面临的挑战

益生菌是活的微生物,当摄入足够数量时,对宿主起有益健康的作用。研究发现母乳中含有活的微生物,使婴幼儿用益生菌被广泛关注。目前,国际上没有对"婴幼儿用益生菌"明确统一的定义及共识。通过阐述婴幼儿用益生菌的种类、常用菌株、安全性、临床研究的现状,指出研究最多的是乳酸杆菌属(Lactobacillus)和双歧杆菌属(Bifidobacterium),诸多报道显示其安全性良好,但是大多益生作用研究来自动物实验,成熟的、具有明确保健功能的益生菌菌株较少,尤其缺乏充分的临床研究。婴幼儿益生菌在研究和产业方面面临3方面挑战:现代肠道优势菌群新发现与传统益生菌菌株的矛盾,健康功能及作用缺乏像药物一样更深层面的精准机制解析,以及婴幼儿益生菌的法规与新菌株临床试验研究的矛盾。尽管面临诸多问题,但是,针对婴幼儿,特别是中国婴幼儿,特有的胃肠功能、免疫系统等尚未发育健全,这一独特的生理特点,开发婴幼儿用益生菌将具有重要前景。     

Prebiotics: Present and future in food science and technology

Because of its resident microbiota, the human colon is one of the body’s most metabolically active organs. The use of diet to fortify certain gut flora components is a popular current aspect of functional food sciences and prebiotics have a significant role. Prebiotics are selectively fermented ingredients that allow specific changes, both in the composition and/or activity in the gastrointestinal microbiota that confers benefits upon host well-being and health. Improved techniques for analysis of the gut microflora, new food manufacturing biotechnologies, and increased understanding of the metabolism of prebiotic inulin and oligosaccharides by probiotics are facilitating development. Such developments are leading us to the time when we will be able to rationally develop prebiotics for specific functional properties and health outcomes. Thus, this review will focus on the progress of prebiotics in food science and technology in understanding the important role of prebiotics in health, beginning at the rationale of gut microflora and interactions with prebiotics. Furthermore, the classification criteria, food applications and safety assessment of prebiotics as food ingredient is also discussed.     

A review on technological parameters and recent advances in the fortification of processed cheese

BackgroundAlthough the consumption of processed foods is growing in overseas markets, the increased awareness of consumers to health and wellbeing in recent years has led to a decline in the growth of processed food sales in the Western market. The added pressure on the food manufacturing industry to increase the perceived healthiness of processed foods has opened up new market potential in the area of fortified processed foods, such as processed cheeses.Scope and approachThis review paper provides an overview of the current methodologies into the production of a processed cheese with added health benefits, including the use of probiotics and prebiotics, vitamin and mineral fortification and the addition of plant macromolecules.Key findings and conclusionsProcessed cheeses with increased health benefits have been of great interest to manufacturers, with reduced salt and reduced fat options commercially available. Although processed cheeses fortified with vitamins, mineral, probiotics and prebiotics are not as widespread, further work in these areas has been identified as a way to produce high value processed cheese products with added health benefits.     

乳酸菌合生元的研究进展

合生元(synbiotics)是由益生菌(probiotics)和益生元(prebiotics)组成的微生物制剂,可同时具有益生菌和益生元的作用,并以肠道为靶点位置发挥益生功能.乳酸菌(lactic acid bacteria,LAB)是肠道中最重要的益生菌成员,无论是用于商品化生产,还是用于基础研究,LAB是最广泛用...     

Dietary fibres as "prebiotics": implications for colorectal cancer

A "prebiotic" is a nondigestible food ingredient whose beneficial effects on the host result from the selective stimulation of growth and/or activity of members of the bacterial community that inhabits the human bowel (the gut microbiota). Although much of the prebiotic literature focuses on nondigestible oligosaccharides, such as oligofructose, most dietary fibres that are fermentable carbohydrates could be considered as prebiotics. Early studies suggested that colonic bacteria were risk factors for colon cancer. However, altering the composition or metabolic activity of the bowel microbiota through the use of dietary fibre might be important in reducing the prevalence of colorectal cancer. Mechanisms for beneficial effects of prebiotics might include changing the activity of exogenous carcinogens through modulating metabolic activation and/or detoxification, or stimulating the production of the short-chain fatty acid, butyrate. However, modern analytical techniques suggest that an important consequence of a modified bacterial community could be a change in the expression not only of a range of different bacterial genes in bowel contents, but also in the bowel mucosa of the host. Analogous with observations with probiotics, the stimulation of cytokines and modification of immune responses could be important in producing beneficial effects. Compared with transitory effects of probiotics, the prebiotic action of fermentable carbohydrates potentially provide the opportunity for sustainable modulation of activity of the gut microbiota. However, their mechanisms of action in humans are speculative, and research aimed at providing an integrated view of the gut microbiota and dietary fibre nutrition of humans needs to be developed.