益生菌的安全性及其功能

介绍了益生菌的安全性和功能。益生菌安全性包括益生菌的来源、非致病性和抗抗生素性；益生菌的主要功能包括其在肠道中的生存力和持久性、免疫调节作用、拮抗其他细菌作用和抗突变作用。     

In vitro comparison of probiotic properties of Lactobacillus casei Zhang, a potential new probiotic, with selected probiotic strains

Since 2004, our research group has isolated 240 Lactobacillus strains from Koumiss, a traditional fermented alcoholic beverage prepared from mare's milk in Inner Mongolia, Xinjiang of China and Mongolia. Among these Lactobacillus strains a novel strain with potential probiotic properties, Lactobacillus casei Zhang, was screened out and studied extensively for its probiotic properties, health-promoting effects and fermentation characteristics. In vitro tests indicated that L. casei Zhang had high tolerance to simulated gastric, intestine juices and bile salts, similar to commercial probiotic strains such as Lactobacillus acidophilus NCFM, Lactobacillus rhamnosus GG, L. casei Shirota and Bifidobacterium animalis Bb12. Higher acid-production activity and proteolytic activity was observed in the fermented milk inoculated with L. casei Zhang during the refrigerated storage than in the samples inoculated with the selected commercial probiotics. The yogurt samples fermented with L. casei Zhang exhibited similarer viable count (1.0 × 10⁹ cfu/mL) as the other samples after 28 d of refrigerated storage. The results suggested that L. casei Zhang showed good potential for application in functional foods and health-related products.     

Potential probiotic Lactobacillus strains from fermented sausages: Further investigations on their probiotic properties

A rational selection of probiotic microorganisms is an important challenge and requires the definition of fundamental information about the physiology and genetics of candidate strains. In this study, selected Lactobacillus (Lact.) strains already characterized in a previous study for their capability to resist low pH and to grow in conditions simulating the intestinal environment, were further investigated to explore their probiotic properties, such as the adhesion capability to intestinal human Caco-2 cell lines and their growth behaviour in the presence of various prebiotic carbohydrates. At first 25 Lactobacillus strains were characterized by pulsed field gel electrophoresis using the endonuclease NotI. Among them, 13 strains belonging to the Lact. plantarum-group were identified at species level by a multiplex PCR assay. Subsequently 11 Lactobacillus strains showing different PFGE restriction pattern and the best acid- and bile-resistances, were chosen to investigate their in vitro adhesion capability to human intestinal epithelial cells and their fermentation properties of five prebiotic substances (FOS, Inulin, IMO, GOS and lactulose) at a concentration of 2%. The 11 strains analysed in this study possessed good adhesion capability to Caco-2 cell layers and, in particular, the eight strains belonging to the Lact. plantarum-group showed the higher final number of viable adhering cells. Moreover a species-related fermentative behaviour was pointed out and the strain Lact. paracasei EL7 was the only one able to grow in the presence of all prebiotics tested. In conclusion the strains of Lactobacillus studied in this research could be further investigated to assess possible in vivo human health benefits.     

营养生物发酵剂在乳品中的应用

<正> 乳品经发酵变酸后,便具有更强的防腐能力,保质期更长。在发酵乳的生产中,一般都是采用乳酸菌进行发酵。经研究发现,有些乳酸菌能促进人体健康,这就是所谓的营养乳酸菌(probiotic lactic acid bacteria)。随着人们生活的富足,对加工食品的要求除了用以充饥外,更要求具有保健功能。富含营养乳酸菌的营养生物发酵剂除了能在任何发酵乳制品中引发发酵过程外,还能增加发酵乳已有的营养价值作用,其发展潜力非常广阔。     

Effects of inulin and oligofructose on the rheological characteristics and probiotic culture survival in low-fat probiotic ice cream

ABSTRACT:  The effects of supplementation of oligofructose or inulin on the rheological characteristics and survival of Lactobacillus acidophilus La-5 and Bifidobacterium animalis Bb-12 in low-fat ice cream stored at –18 °C for 90 d were studied. Addition of oligofructose or inulin to ice cream mix significantly increased apparent viscosity and overrun and developed the melting properties in ice cream during storage ( P < 0.05). However, the highest increase in firmness, the lowest change in melting properties, and the longest 1st dripping time were obtained in probiotic ice cream containing inulin ( P < 0.05). Some textural properties have also improved especially by the end of storage. Freezing process caused a significant decrease in the viability of Lactobacillus acidophilus La-5 and Bifidobacterium animalis Bb-12 ( P < 0.05). Oligofructose significantly improved the viability of L. acidophilus La-5 and B. animalis Bb-12 in ice cream mix ( P < 0.05). Although the viable numbers for both bacteria decreased throughout the storage, the minimum level of 10⁶ CFU/g was maintained for B. animalis Bb-12 in only ice cream with oligofructose during storage.     

益生菌冰淇淋的开发

近年来我国食品工业中,冰淇淋成为继饮料、方便面后发展最为迅猛的产品之一。如何将冰淇淋的嗜好性与产品的营养和功能特性进行有机结合,是冰淇淋产品未来重要的发展趋势。本文从冰淇淋发展简史与近年市场状况,益生茵的种类和作用,益生菌冰淇淋的优势、研究与开发方向等方面进行了概述。     

Importance of food in probiotic efficacy

Foods are carriers for the delivery of probiotics to the human body. In addition, foods help to buffer the probiotic through the gastrointestinal tract, regulate their colonization and contain other functional ingredients, such as bioactive components, which may interact with probiotics to alter their functionality and efficacy. The growth and survival of probiotics during gastric transit is affected by the physico-chemical properties of food carriers. Gastric acid, juices and bile tolerance, adherence to gastrointestinal epithelium and the acid production of probiotics are also affected by the food ingredients used in probiotic delivery. Same probiotic strains could vary in functional and technological properties in the presence of different food ingredients. Prebiotic food ingredients encourage the growth of probiotic bacteria. The appropriate combination of prebiotics and probiotics manifest higher potential for a synergistic effect. Originally, probiotic delivery was consistently associated with foods, particularly dairy foods. But nowadays, there is an increasing trend toward using probiotics in different food systems despite its original sources and even as nutraceuticals, such as in capsules. This changing trend in delivering probiotics may lead to a reduction in functional efficacy due to the exclusion of the potential synergistic effect of the food. Thus, selection of suitable food systems to deliver probiotics is a vital factor that should be considered in developing functional probiotic foods. This review focuses on information related to the effect of processed food products on functional efficacy of probiotics.     

Adhesion and aggregation properties of probiotic and pathogen strains

Autoaggregation has been correlated with adhesion, which is known to be a prerequisite for colonization and infection of the gastrointestinal tract by many pathogens. The coaggregation properties of probiotic strains with pathogens as well as their ability to displace pathogens are of importance for therapeutic manipulation of the aberrant intestinal microbiota. Consequently, the ability to aggregate and coaggregate are desirable properties for probiotics in health-promoting foods. Aggregation assays and bacterial adhesion to hydrocarbons (BATH test) demonstrated significant differences in cell surface properties among the tested commercial probiotic strains. Hydrophobicity increased when the cells were heat-inactivated. All probiotic strains tested showed aggregation abilities with the pathogen strains tested, but the results were strain-specific and dependent on time and incubation conditions. Our results indicate that the ability to autoaggregate, together with cell-surface hydrophobicity and coaggregation abilities with pathogen strains can be used for preliminary screening in order to identify potentially probiotic bacteria suitable for human or animal use.     

Evaluation of in vitro probiotic potential of phytase‐producing bacterial strain as a new probiotic candidate

Sixty‐three phytase‐producing bacterial strains were isolated from natural sources, and their probiotic potential was evaluated. Of these, only fifteen strains were selected on the basis of confirmatory plate assay. Among these, five phytase‐producing strains exhibiting potent probiotic properties were identified as Bacillus cereus P1, Bacillus subtilis P6, B. subtilis P7, Pseudomonas aeruginosa P12 and P. aeruginosa P15 on the basis of morphological, biochemical and molecular characteristics. Maximum phytase activity (2.74 EU mL^?1) with potential probiotic properties, that is more than 70% survivability at pH 2.0, up to 2.0% bile salt tolerance, sporulation efficiency of more than 80% and survival in anaerobic condition (94.31%), was revealed by B. subtilis P6 as compared to the well‐established commercial probiotic strains Lactobacillus sporogenes and Lactobacillus casei. Thus, phytase‐producing B. subtilis P6 with promising probiotic features can be used in food and animal feed applications for betterment of mankind after further validation.     

A new probiotic cheese with antioxidative and antimicrobial activity

The aim of our study was to develop an original probiotic cheese based on the Estonian open-texture, smear-ripened, semisoft cheese "Pikantne." Cheese was produced by two methods using cheese starter cultures (Probat 505) in combination with 0.04% of probiotic Lactobacillus fermentum strain ME-3 (10(9) cfu/mL) with high antimicrobial activity and antioxidative properties. The probiotic Lactobacillus was added into milk simultaneously with starter cultures (cheese A) and into drained curd (cheese B). After addition of probiotic L. fermentum ME-3, the cheese composition, flavor, and aroma were comparable to the control cheese (score values = 4.5, 4.2, and 3.7 for control cheese, cheese A, and cheese B, respectively). Cheese A, which had good sensory properties, was chosen for further testing of viability and probiotic properties. The probiotic strain was found to withstand the technological processing of cheese, surviving and sustaining moderate antimicrobial and high antioxidative activity throughout ripening and storage (the ripened cheese contained approximately 5 x 10(7) cfu/g viable ME-3 cells), although the viability of the ME-3 strain incorporated into the cheese showed a slight decrease between d 24 and 54 after cheese preparation. Semisoft cheese "Pikantne" serves as a suitable carrier of antimicrobial and antioxidative L. fermentum ME-3.     

Challenges in the addition of probiotic cultures to foods

Probiotic cultures are increasingly being added to foods in order to develop products with health-promoting properties. Although the literature is abundant on the beneficial effects of bifidobacteria and Lactobacillus acidophilus on health, little information is available on the challenges industry faces in adding these probiotic cultures to food products. The aim of this article is to examine seven issues that should be addressed when developing functional foods: 1) type or form of probiotic that should be used; 2) addition level required to have a beneficial effect; 3) toxicity; 4) effect of the processing steps on viability; 5) determination, in the product, of the cell populations added; 6) stability during storage; 7) changes in sensory properties of the foods.     

High-intensity ultrasound reduces fermentation time and improves textural properties,antioxidant activity and probiotic survival in fermented probiotic strawberry drink

This study aimed to evaluate the effect of high-intensity ultrasound (HIUS) application with different processing times (2.5, 5, 7.5 and 10 min) on the physicochemical, rheological and textural properties, antioxidant activity (AA) and probiotic survival in strawberry-flavoured fermented probiotic strawberry drink during storage (7°C for 28 days). The application of HIUS resulted in products with lower fermentation times, higher organic acid stability during storage and improved texture (higher firmness and consistency) and functional properties (higher phenolic compounds content and/or AA). Using 2.5 min of processing time would be advisable due to the better probiotic survival to simulated gastrointestinal conditions (probiotic counts higher than 10⁶ CFU mL⁻¹), reduced fermentation times (reduction in 3 h), higher lactic acid content during storage and enhanced AA. The products showed a viable probiotic counts higher than 10⁶ CFU mL⁻¹ during the entire shelf life. HIUS may be considered as an adequate pre-treatment in the development of probiotic fermented probiotic strawberry drink.     

Antimicrobial properties of probiotic strains isolated from breast-fed infants

The protective and probiotic characteristics of intestinal lactobacilli, bifidobacteria and enterococci isolated from breast-fed infant faeces were investigated. Fifty-two selected isolates were identified at the species level and further characterized for their antimicrobial and safety features. Resistance to simulated gastric digestion and adherence to Caco-2 cells were also studied in the selected strains Lactobacillus paracasei INIA P272, Lactobacillus rhamnosus INIA P344, L. rhamnosus INIA P426, Lactobacillus mucosae INIA P459, Bifidobacterium pseudolongum INIA P2, Bifidobacterium breve INIA P18, Enterococcus faecium INIA P445 and Enterococcus faecalis INIA 127 due to their tolerance to GIT (gastrointestinal tract) conditions and interesting antimicrobial properties compared to the other strains investigated. A considerable diversity in the probiotic and antimicrobial properties among breast-fed infant lactic acid bacteria and bifidobacteria isolates was recorded. Some of the selected strains could be promising candidates to be exploited in the development of infant formulas or novel food products.     

Antagonistic and antioxidant effect of probiotic Weissella cibaria JW15

Food Science and Biotechnology - The objective of this study was to evaluate the functional properties of Weissella cibaria JW15 (JW15) by investigating its antagonistic and antioxidant activities....     

Application of shellac for the development of probiotic formulations

In this study, we have improved the enteric properties of shellac and developed probiotic formulations comprising this natural polymer. The effects of plasticizers such as glycerol and glyceryl triacetate, as well as water-soluble polymers such as sodium alginate, hydroxypropyl methylcellulose and polyvinylpyrrolidone on thermodynamic characteristics and coating properties of shellac were evaluated. The data indicate that glycerol showed the best plasticization effect. Hydroxypropyl methylcellulose and polyvinylpyrrolidone had superior miscibility with shellac compared to sodium alginate. Then, three fluid-bed dried bacterial species i.e., Enterococcus faecium, Bifidobacterium bifidum and Lactobacillus reuteri, were coated with formulations comprising different concentrations of shellac and additives. Coatings with shellac containing 5% glycerol or 5% sodium alginate or up to 20% [w/w] polyvinylpyrrolidone protected the microorganisms against acidic pH and provided the best release profile in simulated intestinal fluid. Moreover, these formulations maintained promising cell survival rates after four months of storage at 5 °C. E. faecium and B. bifidum showed more resistance to manufacturing process than L. reuteri.     

益生菌来自健康声明的挑战

本文介绍了全世界不同国家和地区关于健康声明应用的法律规范。健康声明必须依据科学的证据,提供这些证据需要一个漫长而昂贵的过程,而且必须解决一系列的挑战。应用体内、体外不同的方法,筛选和鉴定益生菌。体外研究一般用于筛选目的,获得被测菌株特异性功能等信息,以及评估它们的安全性。差强人意的前期筛选、有限的体外实验及不合适的动物模型经常导致体外结果和体内可行性之间相互矛盾。益生菌最终必须通过适当设计的人体临床研究得到验证。通过实验证据来鉴定益生菌和证实它们在临床试验中的效果,比其他的功能性食品更具挑战,因为这些效果是由活的微生物所介导的,并且微生物本身的状态也会影响这些效果。本文逐一回顾了益生菌健康声明的具体步骤。     

Production of functional probiotic, prebiotic, and synbiotic ice creams

In this work, 3 types of ice cream were produced: a probiotic ice cream produced by adding potentially probiotic microorganisms such as Lactobacillus casei and Lactobacillus rhamnosus; a prebiotic ice cream produced by adding inulin, a prebiotic substrate; and a synbiotic ice cream produced by adding probiotic microorganisms and inulin in combination. In addition to microbial counts, pH, acidity, and physical and functional properties of the ice creams were evaluated. The experimental ice creams preserved the probiotic bacteria and had counts of viable lactic acid bacteria after frozen storage that met the minimum required to achieve probiotic effects. Moreover, most of the ice creams showed good nutritional and sensory properties, with the best results obtained with Lb. casei and 2.5% inulin.     

Comparative survival and evaluation of functional probiotic properties of spray-dried lactic acid bacteria

The effect of spray drying on the viability and retention of key probiotic properties like acid and bile tolerance and cholesterol assimilation of three probiotic lactic acid bacteria (LAB) ( Lactobacillus plantarum CFR 2191, Lactobacillus salivarius CFR 2158 and Pediococcus acidilactici CFR 2193) has been studied. More than 97% survival was exhibited by the three LAB (1% cell suspension) spray dried with maltodextrin and nonfat skimmed (NFSM) as carriers. LAB cultures spray dried with maltodextrin showed significantly greater ( P ≤  0.05) retention of functional properties than those with NFSM. The results highlight a cost-effective way of producing large quantities of selected probiotic cultures with functional properties for neutraceutical application.     

Assessment of adhesion properties of novel probiotic strains to human intestinal mucus

Potential new probiotic strains Lactobacillus brevis PELI, L. reuteri ING1, L. rhamnosus VTT E-800 and L. rhamnosus LC-705 were assessed for their adhesion properties using the human intestinal mucus model. The effect on the adhesion of exposure to acid and pepsin and to milk were tested to simulate gastric and food processing conditions, and the effect of different growth media on adhesion was tested. The properties of the four strains were compared to the well-investigated probiotic L. rhamnosus strain GG. Three of the tested strains showed significant adhesion properties in the mucus model, while L. brevis PELI had intermediate adhesion and L. rhamnosus LC-705 adhered poorly. Pretreatment with different milks decreased the adhesion and low pH and pepsin treatment reduced the adhesion of all tested strains except L. rhamnosus LC-705. No competitive exclusion of pathogenic Salmonella typhimurium or Escherichia coli SfaII was observed. The results indicate that major differences exist between tested proposed probiotic strains. The growth media and the food matrix significantly affect the adhesive ability of the tested strains. This has previously not been taken into account when selecting novel probiotic strains.