A new synbiotic dairy food containing lactobionic acid and Lactobacillus casei

As well as its beneficial health properties, the incorporation of the prebiotic lactobionic acid (LBA) in fermented dairy products can provide a technological advantage due to its gelling capacities. This study aimed to develop a new functional dairy product containing LBA synthesised within the process itself by the bacterium Pseudomonas taetrolens. A probiotic Lactobacillus casei strain was introduced through a sequential fermentation system. After incubation, in the case of the most effective experimental procedure, a synbiotic fermented milk with 30 g/L of prebiotic LBA was obtained, together with an active L. casei population of 10⁹ cfu/mL and <1% lactose content.     

The isolation of lactic acid bacteria from human colonic biopsies after enrichment on lactose derivatives and rye arabinoxylo-oligosaccharides

Lactic acid bacteria (LAB) were isolated from human colon biopsies on LAMVAB by enrichment with different substrates such as lactose derivatives, rye arabinoxylo-oligosaccharides and rye fractions. The selected isolates were tested for their ability to adhere to Caco-2 cells. Only Lactobacillus species were enriched under these conditions. From 161 isolates screened, 28% were identified by ribotyping as Lactobacillus rhamnosus, 29% as L. salivarius, 14% as L. cellobiosus, 13% as L. paracasei and the rest remained unidentified.L. rhamnosus was preferentially enriched by lactulose, L. salivarius by lactobionic acid, L. cellobiosus by lactitol and L. paracasei by arabinoxylo-oligosaccharides. The biopsy-derived strains L. rhamnosus E-97948 andL. paracasei E-97949 have potential for further evaluations in their probiotic and technological properties. Lactulose may have prebiotic effects on colonic LAB by favouring their growth.     

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.     

In vitro screening of probiotics and synbiotics according to anti-inflammatory and anti-proliferative effects

There is emerging evidence of the efficiency of probiotic, prebiotic and synbiotic treatments in inflammatory bowel diseases (IBDs) and one of their long-term complications, colorectal cancer (CRC). In this study, various strains of probiotic lactic acid bacteria, prebiotic glucooligosaccharides (GOS) or a synbiotic combination of the two were screened for anti-inflammatory and anti-proliferative effects in different in vitro models in the context of such diseases. To mimic IBD response to Gram negative bacteria, HT-29 cells were sensitised to inflammatory response to lipopolysaccharide (LPS) by IFNγ which increased expression of TLR4, the LPS biosensor, and were then treated by probiotics, prebiotics and synbiotics. Secreted IL-8 and activated NF-κB were monitored as inflammation biomarkers. A selection of active strains were then subjected to a second inflammatory cell culture model consisting of inflammatory activated transgenic Caco-2 cells transfected by a reporter gene under the control of NF-κB inducible promoter. Quantification of reporter gene expression allowed us to demonstrate some probiotic inhibitory properties or to confirm such characteristics in two different models. Proliferation of cancerous HT-29 cells was monitored by XTT assay. Only three probiotic strains induced a proliferation decrease, but with a lack of reproducibility. Binary or ternary probiotic associations, complemented or not by prebiotic GOS, significantly decreased proliferation, especially with a synbiotic association of Bifidobacterium breve, Lactococcus lactis and oligoalternan, a GOS. This combination was selected for the following experiments. We showed the involvement of both bacterial and carbohydrate compounds of this synbiotic in the observed effect by dose range tests. We demonstrated that this decrease in proliferation may be due to an induction of a differentiated phenotype, as shown by the up-regulation of intestinal alkaline phosphatase, a biomarker of differentiation, monitored by real-time RT-PCR in HT-29 cells treated by the selected synbiotics. Thus, this study demonstrates the ability of probiotics to exert anti-inflammatory effects and shows some anti-proliferative characteristics for a specific synbiotics. These products should be further evaluated in animal models to confirm the in vitro results.     

Application of pure and mixed probiotic lactic acid bacteria and yeast cultures for oat fermentation

Fermentation of a prebiotic containing oat substrate with probiotic lactic acid bacteria and yeast strains is an intriguing approach for the development of new synbiotic functional products. This approach was applied in the present work by using pure and mixed microbial cultures to ferment a heat‐treated oat mash. Results show that the strains studied were appropriate for oat fermentation and the process could be completed for 6–10 h depending on the strain. The viable cell counts achieved within this time were above the required levels of 10⁶–10⁷ cfu ml⁻¹ for probiotic products. Both single lactic acid bacteria strains and mixed cultures of the same strains with yeast were found suitable for oat fermentation. However, the pure LAB cultures attributed better flavour and shelf life of the oat drinks. The content of the prebiotic oat component beta‐glucan remained within 0.30–0.36% during fermentation and storage of the drinks obtained with each of the strains used. Thus, these products would contribute diet with the valuable functional properties of beta‐glucan. Also, the viability of pure and mixed cultures in the oat products was good: levels of cell counts remained above the required numbers for probiotic products throughout the estimated shelf‐life period. Copyright © 2005 Society of Chemical Industry     

The potential effect of FOS and inulin upon probiotic bacterium performance in curdled milk matrices

Inulin and fructooligosaccharides were studied for their prebiotic effect upon growth/survival of probiotic bacteria and technological potential in probiotic food processing, via characterization of glycolysis, proteolysis and lipolysis in curdled milk matrices; the ultimate goal is the manufacture of synbiotic cheeses. Prebiotic compounds did not significantly affect growth/viability of all strains studied, except Lactobacillus acidophilus La-5. Proteolysis indices revealed considerable casein degradation in probiotic and synbiotic matrices inoculated with Bifidobacterium lactis B94 and Lactobacillus casei-01; lower values were achieved in those inoculated with L. acidophilus La-5, yet a synbiotic effect was apparent in NPN values. Lipolysis was not extensive over storage, irrespective of matrix type; however, interesting differences in terms of the qualitative free fatty acids profile were observed. CLA isomers, and α-linolenic and γ−linolenic acids were detected upon 15 d of ripening of all inoculated matrices. Principal component analysis was able to discriminate the various matrices according to degree of maturation, throughout the ripening period. Microbiological and biochemical parameters unfolded a very good technological potential, especially of B. lactis B94 and L. casei-01, to produce novel types of functional dairy matrices - although extrapolation to actual cheeses should still be done with care, because e.g. syneresis was not considered.     

罗非鱼源肠道益生菌的分离鉴定及其体外益生特性分析

为了筛选出优良的鱼源益生菌,作者以吉富罗非鱼(Oreochromis niloticus)为实验材料,进行肠道芽孢杆菌和乳酸菌的分离、鉴定,并对分离得到的菌株进行抑菌活性、耐酸性、耐胆盐、人工胃肠液耐受、溶血活性和抗生素敏感性等体外益生特性分析。结果表明,从罗非鱼肠道中共分离得到109株菌,其中包括79株乳酸菌和30株芽孢杆菌,经过一系列的实验最终筛选出3株乳酸乳球菌（Lactococcus lactis）。生物学特性研究表明,3株菌均无溶血活性,对抗生素具有一定的敏感性,对强酸、胆盐和人工胃肠液具有一定的耐受性,对水产病原菌具有不同的抑菌活性。筛选得到的3株菌丰富了鱼源益生菌资源,它们均可作为优良的鱼源益生菌候选菌株。其中,菌株R1对强酸和人工胃肠液耐受性最强,菌株R29耐胆盐能力最强,可进行进一步的益生特性研究,挖掘其作为食品源益生菌的益生效果。     

Effect of the Lactobacillus rhamnosus strain GG and tagatose as a synbiotic combination in a dextran sulfate sodium-induced colitis murine model

Synbiotics, a combination of prebiotics and probiotics, produce synergistic effects to promote gastrointestinal health. Herein, we investigated the synbiotic interaction between the Lactobacillus rhamnosus strain GG (LGG; a probiotic strain) and tagatose (a prebiotic) in a dextran sulfate sodium (DSS)-induced colitis murine model. Initially, body weight, food intake, and clinical features were dramatically decreased after treatment with DSS, and the addition of LGG, tagatose, or both ameliorated these effects. In our pyrosequencing analysis of fecal microbiota, DSS treatment increased the abundance of Proteobacteria and decreased that of Firmicutes. When LGG and tagatose were administered as synbiotics, the gut microbiota composition recovered from the dysbiosis caused by DSS treatment. In particular, the abundance of Bacteroides, Lactobacillus, and Akkermansia was significantly associated with probiotic, prebiotic, and synbiotic treatments. Taken together, our results suggest that LGG and tagatose as synbiotics can alleviate colitis, and synbiotics could be applied as dietary supplements in dairy foods such as yogurt and cheese.     

The tartaric acid-modified enzyme-resistant dextrin from potato starch as potential prebiotic

Enzyme-resistant dextrin, obtained as a result of heating potato starch with tartaric acid, was tested as the carbon source for selected strains of probiotic bacteria and also bacteria isolated from feces of healthy 30-year old men volunteers. The dynamics of growth of bacterial monocultures in broth containing tartaric acid (TA)-modified dextrin was estimated. It was also investigated whether probiotic lactobacilli and bifidobacteria cultured with intestinal bacteria in the presence of resistant dextrin would be able to dominate the intestinal isolates. Prebiotic fermentation of resistant dextrin was analyzed using prebiotic index (PI). Fermentation products were determined by HPLC. It was shown that all of the tested bacteria were able to grow and utilize TA-modified dextrin as a source of carbon, albeit to varying degrees. In co-cultures of intestinal and probiotic bacteria, the environment was found to be dominated by the probiotic strains of Bifidobacterium and Lactobacillus, which is a beneficial effect.     

Probiotic potential of Lactobacillus paracasei FM-LP-4 isolated from Xinjiang camel milk yoghurt

Fifty three probiotic lactic acid bacteria (LAB) strains with high anti-oxidative activity from Xinjiang camel milk yoghurt were screened and identified. Four strains showed higher 2,2-diphenyl-1-picrylhydrazyl scavenging activity and reducing power than the reference strain Lactobacillus rhamnosus GG (ATCC53103) with strain FM-LP-4, identified as Lactobacillus paracasei by 16S rDNA nucleotide sequencing, showing the highest. Strain FM-LP-4 also showed higher stress tolerance properties (acidity, bile, and osmotic pressure) and adhesion properties than L. rhamnosus GG. The in vivo antioxidant activity of FM-LP-4 was further assayed in d-galactose-induced oxidative damaged mice. Administration of FM-LP-4 significantly enhanced the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and inhibited the biosynthesis of malondialdehyde (MDA) and protein carbonyl in a dose-dependent manner. Additionally, FM-LP-4 strain could significantly decrease the endotoxin level in the serum of mice. Overall, strain FM-LP-4 is a promising probiotic candidate for preparations of functional foods and antioxidant supplements.     

Lipolysis in probiotic and synbiotic cheese: The influence of probiotic bacteria, prebiotic compounds and ripening time on free fatty acid profiles

The influence of probiotic bacteria (Lactobacillus casei-01, Bifidobacterium lactis B94), prebiotic compounds (FOS and inulin) and ripening time (0-60 days) on the free fatty acid (FFA) profile of cheese, with special emphasis on the conjugated linoleic acid (CLA) content, was investigated. After 60 days of ripening, 10⁹-10¹⁰ cfu g⁻¹ cheese were recorded in both probiotic and synbiotic cheeses, despite harsh conditions of low pH values (4.1-5.1) and low moisture content (<30%, w/w). Increases in total FFA and CLA were observed throughout the ripening period, especially in synbiotic cheeses containing FOS and inulin (50:50) inoculated with B. lactis B94. The addition of FOS alone or combined with inulin did not significantly affect probiotic strain growth and viability during the ripening period; however, the advantage of the addition of prebiotic compounds in probiotic cheese manufacture is that it may allow the production of cheeses with improved performance as far as functional CLA compounds are concerned, as well as an improved nutritional quality reflected in a lower atherogenicity index.     

Probiotic potential and biochemical and technological properties of Lactococcus lactis ssp. lactis strains isolated from raw milk and kefir grains

Lactococcus lactis ssp. lactis is one of the most important starter bacteria used in dairy technology and it is of great economic importance because of its use in the production of dairy products, including cheese, butter, cream, and fermented milks. Numerous studies have evaluated the biochemical and probiotic properties of lactococci; however, limited studies on the probiotic characteristics of lactococci were conducted using strains originating from raw milk and dairy products. Characterizing the probiotic properties of strains isolated from raw milk and fermented milk products is important in terms of selecting starter culture strains for the production of functional dairy products. In this study, biochemical properties (including antibiotic sensitivity, lipolytic activity, amino acid decarboxylation, antioxidant activity) and probiotic properties (including antimicrobial activity, growth in the presence of bile salts, bile salts deconjugation, and hydrophobicity) of 14 Lactococcus lactis strains isolated from raw milk and kefir grains were investigated. Strains originating from kefir grains had better characteristics in terms of antimicrobial activity and bile salt deconjugation, whereas strains from raw milk had better hydrophobicity and antioxidant activity characteristics. None of the strains were able to grow in the presence of bile salt and did not show amino acid decarboxylation or lipolytic activities. Biochemical and probiotic properties of L. lactis strains varied depending on the strain and some of these strains could be used as functional cultures depending on their properties. However, these strains did not possess all of the properties required to meet the definition of a probiotic.     

Innovative production of multistrain synbiotic product using Thai-pigmented rice and rice bran oil

This study found that the isolated probiotics Lactobacillus paracasei KUKPS6201, L. acidophilus KUKPS6107, L. reuteri KUKPS6103, L. rhamnosus KUKPS6007, L. salivarius KUKPS6202, Bacillus coagulans KPSTF02 and Saccharomyces boulardii KUKPS6005 had high potential for probiotic properties. All strains had antibacterial activity and high antioxidant activity of 1.654 ± 0.017 mg Trolox mL⁻¹ probiotic extract. The selected strains could survive in a simulated gastrointestinal tract under anaerobic conditions and showed no haemolytic activity. Furthermore, the probiotic strains were strongly auto-aggregated and also showed co-aggregated ability with pathogenic bacteria. The probiotic microorganisms demonstrated high ability to adhere to Thai-pigmented rice grains. The results of analysis of these probiotics showed that Riceberry rice bran oil was an excellent prebiotic. A synbiotic product containing Thai-pigmented rice grains (cultivar Riceberry, Luem Pua and Black Jasmine) and rice bran oil was produced. After 8 weeks of storage, the viability of the probiotics in terms of multistrains was 7.36 ± 0.04 log CFU g^–1 (85.78% survival rate). Microbiological safety testing indicated that the amounts of contaminants were acceptable. This study provided the first scientific report on the feasibility of applying Thai-pigment rice, rice bran oil and mixed-culture probiotics as a novel functional synbiotic product.     

Identification and functional characterization of Lactobacillus strains isolated from milk and Gioddu,a traditional Sardinian fermented milk

Raw milk from Sardinian cows and sheep, and sheep's milk yoghurt (Gioddu), are food products that are poorly characterized in terms of the presence of mesophilic Lactobacillus strains, and may be good sources from which to isolate novel bacterial strains. Sixteen Lactobacillus strains were identified by genotypic and phenotypic methods from samples of sheep's milk (n=7), fermented sheep's milk (n=7) and one sample of cows’ milk. These strains were further characterized for the presence of functional traits useful for probiotic applications, such as resistance to simulated gastric acid, resistance to bile salts, and adhesion of two different cell lines (Caco-2 and MIM/PPK). Moreover, selected aspects correlated with safety (antimicrobial susceptibility and presence of plasmids) and ecological roles (ability to produce biofilms and bacteriocin-like substances) were tested. All but 1 of the 16 strains were unambiguously allotted to three species, L. paracasei (5 strains), L. plantarum (8 strains), and L. reuteri (2 strains). Many of the strains exhibited characteristics suggesting that they would survive in the gastrointestinal tract and also had the capability to attach to various cells. Greater variability was observed for the other traits analyzed. These data suggest that Sardinian artisan dairy products are interesting sources for the isolation of bacterial strains with characteristic and differentiated functional traits.     

Improving functionality of chocolate: A review on probiotic,prebiotic, and/or synbiotic characteristics

BackgroundChocolate is consumed by people of all ages in all segments of society throughout the world. The popularity of this food is mainly associated with its potential to arouse sensory pleasure and positive emotions. Increasing awareness of the link between healthy eating and well-being is reflected in the current views of the general consumers. Consumers perceive functional foods as a member of the specific food category to which they belong. Also, in developed economies, a key trend at the moment is confectionery products that deliver functional benefits for health and well-being, such as functional chocolate.Scope and approachIn this review, studies related with production of prebiotic, probiotic and synbiotic chocolates as a functional food were investigated and positive and negative aspects of these functional products when compared with standard one were stated, which could shape the following related studies in food area and the production of prebiotic, probiotic and synbiotic chocolates in the food industry.Key findings and conclusionsWhen the studies related with this topic were investigated it could be concluded that the studies associated with chocolate which could play a role in transportation of probiotics and prebiotics might be supported by studies in which bioavailability and bioaccessibility characteristics of them in vivo and in vitro media will be determined. Moreover, in order to improve bioavailability and bioaccessibility properties product quality optimization studies might be required in the future.     

Short communication: In vitro and in vivo probiotic potential of Lactobacillus plantarum B7 and Lactobacillus rhamnosus D1 isolated from Minas artisanal cheese

Some Lactobacillus strains may contribute to the health of the host when administered in adequate concentrations, demonstrating their probiotic potential. In contrast, Listeria monocytogenes is a foodborne pathogen that can cause enteropathy, meningoencephalitis, abortion, and septicemia. The aim of this survey was to evaluate the in vitro and in vivo probiotic potential of Lactobacillus plantarum B7 and Lactobacillus rhamnosus D1, isolated from Minas artisanal cheese of the Serra da Canastra (Minas Gerais, Brazil), against Lis. monocytogenes. We submitted B7 and D1 to in vitro testing (antibiogram, tolerance to bile salts and artificial gastric fluid, and spot-on-lawn) and in vivo testing (relative weight gain in mice). Both Lactobacillus strains demonstrated in vitro inhibitory activity against Lis. monocytogenes, as well as sensitivity to antimicrobials and resistance to gastric acids and bile salts. In the in vivo assays, mice treated with D1 gained more weight than mice in the other groups. These results indicate that D1 could have higher probiotic potential than B7 because improvements in feed conversion may help animals fight infection.     

Probiotic potential of Lactobacillus delbrueckii strains and their phage resistant mutants

Three commercial phage sensitive strains of Lactobacillus delbrueckii and spontaneous phage resistant mutants isolated from them were studied by focusing on their biological and probiotic features. After incubation in a simulated gastric solution (pH 2.0), viable cell counts decreased moderately, but a protective effect on strains was observed when milk was added. A limited resistance to bile was observed, while most of the strains tolerated lysozyme, and grew in the presence of bile salts and fermented prebiotics. Some strains showed high hydrophobicity values and β-galactosidase activity. The strong antibacterial activity displayed toward pathogens was due to the production of lactic acid. Sensitive strains and their phage resistant variants were able to adhere to Caco-2/TC-7 monolayers and significantly inhibited the invasion of Salmonella enterica serovar Enteritidis into Caco-2/TC-7 cells. All strains tested showed potential probiotic features, suggesting a potential probiotic role of L. delbrueckii.     

Characterization and probiotic potential of Lactobacillus plantarum strains isolated from cheeses

Ninety-eight Lactobacillus plantarum strains isolated from Italian and Argentinean cheeses were evaluated for probiotic potential. After a preliminary subtractive screening based on the presence of msa and bsh genes, 27 strains were characterized. In general, the selected strains showed high resistance to lysozyme, good adaptation to simulated gastric juice, and a moderate to low bile tolerance. The capacity to agglutinate yeast cells in a mannose-specific manner, as well as the cell surface hydrophobicity was found to be variable among strains. Very high β-galactosidase activity was shown by a considerable number of the tested strains, whereas variable prebiotic utilization ability was observed. Only tetracycline resistance was observed in two highly resistant strains which harbored the tetM gene, whereas none of the strains showed β-glucuronidase activity or was capable of inhibiting pathogens. Three strains (Lp790, Lp813, and Lp998) were tested by in vivo trials. A considerable heterogeneity was found among a number of L. plantarum strains screened in this study, leading to the design of multiple cultures to cooperatively link strains showing the widest range of useful traits. Among the selected strains, Lp790, Lp813, and Lp998 showed the best probiotic potential and would be promising candidates for inclusion as starter cultures for the manufacture of probiotic fermented foods.     

A survey of non-starter lactic acid bacteria in traditional cheeses: Culture dependent identification and survival to simulated gastrointestinal transit

Cultivable NSLAB in traditional Pasta filata and ewes' milk cheeses were studied by both PCR-DGGE of cells from Rogosa agar and by isolation and molecular identification after a simulated gastric juice (SGJ) treatment of the cheese. Two to six species were retrieved from each sample. The majority of isolates were identified as Lactobacillus paracasei, Lactobacillus fermentum, Lactobacillus rhamnosus, Enterococcus or Pediococcus. Bile tolerance and bile salt hydrolase (BSH) activity were tested on 88 strains: 64% were able to grow with ≥0.15% bile and 40% were BSH positive. The effect of simulated digestion was tested on 15 strains. Inactivation ranged from 0.15 to 2.93 log cycles; most of the lethality was associated with pancreatic juice treatment. Although SGJ treatment alone may not provide a correct estimate of tolerance to gastrointestinal transit, it allowed selection of strains with a high tolerance to gastric juice, which may be tested as probiotic candidates.     

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.