食品工业中常用益生素和化学益生素研究进展

本文综述益生素和化学益生素的定义、作用机理及近年在食品工业中常用益生素和化学 益生素的最新研究进展。     

Physiological Changes of Surface Membrane in Lactobacillus with Prebiotics

Synbiotics are always considered to be beneficial in healthy manipulation of gut environment; however, the purpose of this research was to investigate the dominance of synbiotic over the individual potential of probiotics and prebiotics. Four different types of prebiotics, fructo‐oligosaccharides, raffinose, inulin, and cellobiose, were evaluated based on their varying degree of polymerization, combined each with 2 different Lactobacilli strains, including Lactobacillus paracasei 276 and Lactobacillus plantarum WCFS1. The effects of synbiotics combination on the surface structure were evaluated by analyzing auto‐aggregation, membrane hydrophobicity, and adhesion to Caco‐2 cells. Our results showed that both Lactobacilli exhibited significantly greater degree of attachment to Caco‐2 cells (23.31% and 16.85%, respectively) when using cellobiose as a substrate than with other prebiotics (P < 0.05). Intestinal adhesion ability was in correlation with the percent of auto‐aggregation, both Lactobacillus exhibited higher percent of auto‐aggregation in cellobiose compared to other prebiotics. These behavioral changes in terms of attachment and auto‐aggregation were further supported with the changes noticed from infrared spectra (FT‐IR).     

Therapeutic Spectrum of Nondigestible Oligosaccharides: Overview of Current State and Prospect

Functional oligosaccharides have emerged as valuable components of food and dietary supplements. Their resistance to digestion and fermentation by colonic microbes has given them the nutritional edge. Apart from implications as dietary fibers, sweeteners, and humectants, they are hailed as prebiotics. Their beneficial effects extend from antioxidant, anti‐inflammatory, immunomodulatory, antiallergic, hypotensive, hyperlipemic, neuroprotective to anticancer. The rising popularity of bioactive oligosaccharides has accelerated the search for their generation from new, sustainable sources. The surfacing crucial role in healthcare and unprecedented demand necessitates deeper investigation. The present review embodies an overview on various aspects of production, properties with emphasis on therapeutic applications of functional oligosaccharides. The biological efficacy and possible mechanisms of action of oligosaccharides have also been discussed.     

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.     

鳙鱼肠道菌群多样性及潜在益生菌的分离鉴定

该研究利用三代16S rRNA扩增子测序技术分析天然池塘生境鳙鱼肠道菌群特征,并从中分离潜在益生菌。该生境鳙鱼肠道菌群以厚壁菌门（Firmicutes,10.28%）和变形菌门（Proteobacteria,21.47%）为主。在属水平上,以未命名菌属ZOR006（21.63%）、严格梭菌属（Clostridium_sensu_stricto_1,10.84%）、罗姆布茨菌属（Romboutsia,10.34%）、类梭菌属（Paeniclostridium,9.63%）、甲基孢囊菌属（Methylocystis,8.74%）为主。为分离到既有利于营养物质的吸收又能抑制病原微生物的鳙鱼源芽孢杆菌（Bacillus）,对从该生境鳙鱼肠道中分离的菌株进行产酶、抑菌等功能相关益生特性试验。试验共分离出3株细菌,YB6、YB42和YB56,通过菌落形态观察及16S rRNA序列分析,鉴定结果显示其分别为贝莱斯芽孢杆菌（Bacillus velezensis strain）、暹罗芽孢杆菌（Bacillus siamensis strain）和解淀粉酶芽孢杆菌（Bacillus amyloliquefaciens strain）。试验结果表明,3株菌均具有良好的产胞外蛋白酶、淀粉酶、纤维素酶及抑制病原菌的能力,可以作为促消化和病原拮抗益生菌做进一步的研究。     

益生菌对Ⅱ型糖尿病影响的研究进展

肠道菌群在调节机体新陈代谢、维持人体健康和疾病发生中起着重要作用。近年来随着对肠道微生物研究的深入,人们发现肠道菌群与代谢综合征、过敏、神经退行性疾病等疾病的发生和发展密切相关。目前,肠道菌群与人体健康之间的联系成为研究热点,但肠道菌群与这些疾病的关系以及相应的发病机制尚不清楚。对肠道菌群结构和代谢物的16S rRNA及宏基因组进行分析,揭示了肠道菌群组成与糖尿病之间的相关性。益生菌作为人体肠道共生菌中一类特殊的菌群,可以调节胃肠道稳态、营养物质代谢和能量平衡。因此,以肠道微生物为靶点缓解或治疗糖尿病有其独特的优势。本文总结了益生菌在糖尿病防治中的研究进展,为糖尿病的相关研究提供参考。     

Growth, Viability and Activity of Bifidobacterium spp. in Skim Milk Containing Prebiotics

Growth, activity and mean doubling time (T_d) of five Bifidobacterium species in the presence of four types of prebiotics, and concentrations of acetic and lactic acids were determinted during fermentation and after 4 weeks of refrigerated storage. The T_d was lowest for B. animalis with raftilose and inulin. Retention of viability of bifidobacteria was greatest with hi‐amylose corn starch (hi‐maize). The average pH of skim milk at the end of 4 wks storage averaged 4.34 (for B. animalis with raftilose) to 4.07 (for B. longum with inulin). The highest levels of acetic acid and lactic acid were produced by B. pseudolongum with lactulose and B. infantis with lactulose, respectively.     

Optimization of Incorporated Prebiotics as Coating Materials for Probiotic Microencapsulation

ABSTRACT: The purpose of this research was to improve probiotic microencapsulation using prebiotics and modern optimization techniques to determine optimal processing conditions, performance, and survival rates. Prebiotics (fructooligosaccharides or isomaltooligosaccharides), growth promoter (peptide), and sodium algi-nate were incorporated as coating materials to microencapsulate 4 probiotics ( Lactobacillus acidophilus, Lacto-bacillus casei, Bifidobacterium bifidum , and Bifidobacterium longum ). The proportion of the prebiotics, peptide, and sodium alginate was optimized using response surface methodology (RSM) to 1st construct a surface model, with sequential quadratic programming (SQP) subsequently adopted to optimize the model and evaluate the survival of microencapsulated probiotics under simulated gastric fluid test. Optimization results indicated that 1% sodium alginate mixed with 1% peptide and 3% fructooligosaccharides as coating materials would produce the highest survival in terms of probiotic count. The verification experiment yielded a result close to the predicted values, with no significant difference ( P > 0.05). The storage results also demonstrated that addition of prebiotics in the walls of probiotic microcapsules provided improved protection for the active organisms. These probiotic counts remained at 10⁶ to 10⁷ colony-forming units (CFU)/g for microcapsules stored for 1 mo and then treated in simulated gastric fluid test and bile salt test.     

6种低聚糖对肠道益生菌生长情况的影响及代谢产物分析

该研究考察了水苏糖、低聚半乳糖、低聚果糖、菊粉、低聚木糖、抗性糊精等6种低聚糖对9种肠道益生菌的体外增殖作用,评价了不同低聚糖对不同益生菌的促生长和促产酸能力,并分析该54个发酵体系中乙酸和乳酸的最大产生量.结果 表明,6种低聚糖对各益生菌的促生长和促产酸能力不同,以水苏糖和低聚半乳糖的效果最为显著,表现出广谱的代谢能...     

国外益生元膳食来源与摄入量现状

介绍了益生元的概念及其特征,根据不同国家的地区现状对益生元的膳食来源和摄入量进行了探讨,为满足人们对益生元的健康需求结合天然食品、营养强化食品以及营养补充剂给出了膳食建议,讨论了影响国外消费者选择益生元食品的原因。     

Fermentation Capabilities of Bifidobacteria Using Nondigestible Oligosaccharides, and Their Viability as Probiotics in Commercial Powder Infant Formula

The species Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum biotype infantis (Spanish type culture collection), and Bifidobacterium longum (Morinaga nutritional foods) were evaluated in vitro in the presence of 4 commercial nondigestible oligosaccharides (NDO) (short‐chain fructooligosaccharides [SCFOS] [degree of polymerization, DP: 2–3], inulin [DP: 10–0], oligofructose [DP: 2–0] and 4′‐galactosyllactose [4′‐GOS] [DP: 3–]). Each species was incubated anaerobically in tryptone phytone yeast (TPY) broth for 7 d with NDO. Every 24 h, bifidobacteria growth was evaluated by means of broth turbidity as optical density at 600 nm. Moreover, another sample was collected for pH culture measurement. Results showed that inulin was the substrate with the least effect on the stimulation of bifidobacteria growth and pH decrease. On the last day of incubation, the substrate 4′‐GOS stimulated bacterial growth more strongly and produced a larger decrease in culture broth pH than the other substrates. On the other hand, B. bifidum and B. longum showed a greater growth with 4′‐GOS. In a 2nd study, these 2 bifidobacteria species were added to a powder follow‐on probiotic infant formula. The viability of the bifidobacteria during the formula's period of consumption was evaluated in 2 studies of 6 and 14 d. Both corresponded to the minimum and maximum time of consumption of the formula according to the manufacturer's directions. It was found that, although in both studies bifidobacteria counts decreased significantly (P < 0.05) with time, they were always above the recommended addition level (10⁶ colony‐forming units [CFU]/g) at the time of sale for dairy products by the Intl. Standard of Fédération Internationale de Laiterie/International Dairy Federation (FIL/IDF). Moreover, because the pH of the reconstituted formula was always close to neutrality (from 6.74 to 7.06), the number of bacteria did not drop below the recommended level.     

Probiotics: The scientific evidence in the context of inflammatory bowel disease

Inflammatory bowel disease (IBD) generally comprises Crohn's disease (CD) and ulcerative colitis (UC), and their main characteristic is the intestinal mucosa inflammation. Although its origin is not yet fully known, there is growing evidence related to genetics, intestinal microbiota composition, and the immune system factors such as precursors for the initiation and progression of intestinal conditions. The use of certain probiotic microorganisms has been touted as a possible and promising therapeutic approach in reducing the risk of inflammatory bowel disease, specifically ulcerative colitis. Several mechanisms have been proposed to explain the benefits of probiotics, indicating that some bacterial strains are able to positively modulate the intestinal microbiota and the immune system, and to produce metabolites with anti-inflammatory properties. The aim of this paper is to bring together the various results and information, based on scientific evidence, that are related to probiotics and inflammatory bowel disease, emphasizing the possible mechanisms involved in this action.     

益生菌对糖脂代谢紊乱相关疾病的缓解作用及机制

糖脂代谢紊乱是常见内源性疾病发病的重要因素,其相关疾病的发病率逐年上升,严重影响患者的生活质量。益生菌是对人体健康有益的微生物,可通过调节肠道微生物起到降低血糖、调节血脂、改善氧化应激及炎症的作用。作者综述了益生菌在高脂血症、糖尿病、高血压这3种糖脂代谢紊乱相关疾病中的具体作用效果及其相关机制。作为一种非药物性降糖、降脂方法,益生菌为糖脂代谢紊乱相关疾病的干预治疗提供了新思路。     

益生菌对雌激素代谢及相关疾病的影响

近年来,因雌激素代谢紊乱引起的女性健康问题受到国内外学者的广泛关注。有研究发现肠道微生物及其多样性对女性雌激素代谢及其代谢产物有重要影响,而经过益生菌干预后可改善肠道菌群结构,促进有益菌生长,进而改善机体雌激素代谢。此外,益生菌能够调节有机体内血液循环及内分泌循环系统,从而改善因雌激素代谢紊乱而诱发的一系列疾病。本文对国内外益生菌与雌激素相关疾病的研究现状进行综述,并列举了益生菌对改善雌激素代谢紊乱在临床治疗中的应用,为雌激素代谢紊乱及相关疾病的防治提供一定参考。     

复合益生菌制剂对人体肠道菌群组成的调节作用

为了研究复合益生菌制剂对人体肠道菌群的调节作用,该实验招募到15名健康志愿者,连续服用4周的复合益生菌制剂。干预前后收集志愿者的粪便样品,通过16S rDNA扩增子测序技术分析干预前后粪便中肠道菌群组成的变化。其结果表明：复合益生菌制剂干预4周后,人体肠道菌群的Shannon指数和Evenness指数不变（p>0.05）;在门水平上,厚壁菌门（Firmicutes）和放线菌门（Actinobacteria）的相对丰度增加;在属水平上,除乳杆菌属（Lactobacillus）和双歧杆菌属（Bifidobacterium）的相对丰度增加以外,复合益生菌制剂干预对柯林斯菌属（Collinsella）、瘤胃球菌属（Ruminococcus）、多尔氏菌属（Dorea）和真细菌属（Eubacterium）等肠道内产氢气细菌的相对丰度也产生影响。由此认为,该复合益生菌制剂具有调节肠道菌群组成的作用,能够提高肠道内一些有益菌的丰度。     

Effect of Co-encapsulation of Probiotics with Prebiotics on Increasing the Viability of Encapsulated Bacteria under In Vitro Acidic and Bile Salt Conditions and in Yogurt

ABSTRACT: Three different complementary prebiotics (selected by in vitro fermentation) were separately co-encapsulated with Lactobacillus acidophilus CSCC 2400 or CSCC 2409 and tested for their efficacy in improving the viability of bacteria under in vitro acidic conditions. Addition of Hi-maize^TM starch to capsules containing Lactobacillus spp. provided maximum protection to the encapsulated bacteria after 3 h of incubation at pH 2.0 compared with other 2 prebiotics, Raftiline® and Raftilose®. Viable counts of Lactobacillus spp. increased significantly ( P < 0.05) with Hi-maize concentration of up to 1.0% (w/v). Further increase in Hi-maize concentration did not protect the encapsulated bacteria effectively. Effects of 3 different polymers (chitosan, poly-L-lysine, and alginate) were also tested for their efficacy in protecting the encapsulated bacteria at pH 2.0. Addition of Hi-maize (1.0% w/v) to capsules containing Lactobacillus spp. and further coating with chitosan significantly increased ( P < 0.05) the survival of encapsulated bacteria under in vitro acidic and bile salt conditions and also in stored yogurt compared with alginate encapsulated cells.     

Impact of human aging and modern lifestyle on gut microbiota

Human evolution and lifestyle changes caused by the agricultural and industrial revolutions have led to great advances in medicine and increased life expectancy, whilst also profoundly altering the ecological relationships and disease patterns of populations. Studies involving populations that still enjoy a rural way of life and with traits similar to the Paleolithic period reveal them to present a more robust, resistant and diverse gut microbiota, in comparison to highly industrialized civilizations. The human diet has expanded and broadened to include the consumption of high-calorie foods, particularly from animal sources such as game meat and eggs. For some time, authors have been alert to the fact that a modern lifestyle leads to reduced intake of beneficial bacteria, suggesting that nonpathogenic bacteria are being eradicated. Furthermore, therapeutic procedures, including the use of probiotics and prebiotics, have been proposed to lead to recovery of this microbiota, which is altered due to both the ageing process and lifestyle related aspects. Accordingly, this article aims to review the impact of human aging and modern lifestyle on gut microbiota, within an evolutionary, ecological, epidemiological and therapeutic context.