Functional petit-suisse cheese: measure of the prebiotic effect

Prebiotics and probiotics are increasingly being used to produce potentially synbiotic foods, particularly through dairy products as vehicles. It is well known that both ingredients may offer benefits to improve the host health. This research aimed to evaluate the prebiotic potential of novel petit-suisse cheeses using an in vitro fermentation model. Five petit-suisse cheese formulations combining candidate prebiotics (inulin. oligofructose. hone) and probiotics (Lactobacillus acidophilus, Bifidobacterium lactis) were tested in vitro using, sterile. stirred, batch culture fermentations with human faecal slurry. Measurement of prebiotic effect (MPE) values were generated comparing bacterial changes through determination of maximum growth rates of groups, rate of substrate assimilation and production of lactate and short chain fatty acids. Fastest fermentation and high lactic acid production, promoting increased growth rates of bifidobacteria and lactobacilli. were achieved with addition of prebiotics to a probiotic cheese (made using starter + probiotics). Addition of probiotic strains to control cheese (made using just a starter culture) also resulted in high lactic acid production. Highest MPE values were obtained with addition of prebiotics to a probiotic cheese, followed by addition of prebiotics and/or probiotics to a control cheese. Under the in vitro conditions used, cheese made with the combination of different prebiotics and probiotics resulted in the most promising functional petit-suisse cheese. The study allowed comparison of potentially functional petit-suisse cheeses and screening of preferred synbiotic potential for future market use. (c) 2007 Elsevier Ltd. All rights reserved

In vitro fermentation of prebiotic carbohydrates by intestinal microbiota in the presence of Lactobacillus amylovorus DSM 16998

The aim of this study was to evaluate the assimilation of the prebiotics fructooligosaccharides (FOS), galactooligosaccharides (GOS), and Konjac glucomannan oligosaccharides (KGMO) by three human (H1, H2 and H3) and pig (P1, P2 and P3) faecal microbiotas in the presence of the potentially probiotic strain Lactobacillus amylovorus DSM 16698, using an in vitro batch fermentation model. Total bacteria and L. amylovorus populations were quantified using qPCR and biochemical features (pH, production of short chain fatty acids (SCFA), lactate, ammonia, and carbohydrate assimilation) were determined. L. amylovorus did not have a competitive advantage under in vitro conditions, reflected by its reduced relative abundance during fermentation despite the carbohydrate sources added. Pig microbiota sustained more stable probiotic counts. Intermittently produced lactate was possibly assimilated by the microbiota and converted to other SCFA as the carbohydrates were assimilated, with H3 probably having a methanogenic metabolism with high lactate and acetate consumption except in the presence of FOS, which assimilation resulted in the highest total SCFA for this volunteer. Addition of FOS also resulted in lower pH and ammonia, which might have been used as nitrogen source by pig microbiota. KGMO needed longer fermentation periods to be completely assimilated by both human and porcine faecal microbiotas. Overall, our results reinforce the notion that care must be taken when generalising the effects claimed for a given probiotic or potentially probiotic strain, including the combination with different prebiotic substrates, since they may vary considerably among individuals, which is important when studying potentially pro- and prebiotic combinations for application as functional foods and feed ingredients

In vitro evaluation of gastrointestinal survival of Lactobacillus amylovorus DSM 16698 alone and combined with galactooligosaccharides, milk and/or Bifidobacterium animalis subsp. lactis Bb-12

Probiotic properties of Lactobacillus amylovorus DSM 16698 were previously demonstrated in piglets. Here, its potential as a human probiotic was studied in vitro, using the TIM-1 system, which is fully validated to simulate the human upper gastrointestinal tract. To evaluate the effect of the food matrix composition on the survival of L. amylovorus DSM 16698 in TIM-1, the microorganism was inoculated alone or with prebiotic galactooligosaccharides (GOS), partially skimmed milk (PSM) and/or commercial probiotic Bifidobacterium animalis subsp. lactis Bb-12 (Bb-12). Samples were collected from TIM-1 for six hours, at one-hour intervals and L. amylovorus populations were enumerated on MRS agar plates with confirmation of identity of selected isolates by randomly amplified polymorphic DNA (RAPD) fingerprinting. The cumulative survival for L. amylovorus alone (control) was 30% at the end of the experiment (t = 6 h). Co-administration of L. amylovorus with GOS, PSM and/or Bb-12 increased its survival in comparison with the control significantly from the 4th hour after ingestion onwards (P <0.05). Furthermore, by the use of High Performance Anion Exchange Chromatography, both L. amylovorus and Bb-12 were observed to promptly degrade GOS compounds in samples collected from TIM-1, as assessed at t = 2 h. Hence, food matrix composition interfered with survival and growth of L. amylovorus during passage through TIM-1, providing leads towards optimization of probiotic properties in vivo

Efeitos do extrato da parede de levedura na digestibilidade, no escore fecal e na palatabilidade de dietas para gatos Effects of spray-dried yeast cell wall on digestibility, score of feces, and palatability of diets for cats

Para avaliar o efeito do extrato seco da parede de levedura (EPL) sobre a digestibilidade, o escore fecal e a palatabilidade de dietas para gatos, foram realizados três ensaios experimentais. No primeiro, 20 animais adultos foram distribuídos ao acaso em quatro tratamentos: dieta comercial úmida (controle) e dieta-controle + 0,2, ou dieta-controle + 0,4 ou dieta-controle + 0,6% de EPL na matéria seca. No segundo, utilizaram-se alimento seco e as mesmas proporções com o mesmo delineamento do primeiro experimento. No ensaio 3, de palatabilidade, 20 gatos adultos receberam simultaneamente dieta comercial úmida sem e com a inclusão de 0,4% de EPL. No experimento 1, não foram observadas diferenças quanto à digestibilidade da matéria seca, proteína bruta, extrato etéreo, matéria orgânica e energia bruta, assim como no escore fecal; no segundo, houve aumento linear (P<0,46) no coeficiente de digestibilidade da matéria seca, e, no terceiro, observou-se efeito negativo da inclusão de 0,4% sobre a palatabilidade da dieta (P<0,004). Conclui-se que a inclusão de EPL em dietas úmidas não influi na digestibilidade, mas pode comprometer a palatabilidade, e que em dietas secas há melhora da digestibilidade da matéria seca.<br>The effects of spray-dried yeast cell wall (YCW) were evaluated on digestibility, score of feces, and palatability of diets for cats were evaluated. Three trials were carried out. In the first, 20 adult cats were randomly allotted in four treatments: wet commercial diet (control) and control plus 0.2, 0.4, or 0.6% of YCW in dry matter. In the second, a commercial dry diet was tested in an equal arrangement concerning concentration of YCW and number of animals of the first trial. In the third, 20 adult cats were fed at the same time a wet diet with or without 0.4% YCW. In the first trial, no differences among treatments for dry matter, crude protein, ether extract, organic matter, gross energy digestibility, and faecal score were observed. In second trial, positive linear effect on dry matter digestibility (P=0.046) was observed. In the third, negative effect of 0.4% YCW inclusion (P=0.004) on palatability of diet was observed. It was concluded that YCW inclusion in wet diet did not effectively alter the nutrients digestibilities but it decrease the palatability. However, the YCW inclusion in dry diets can be important to improve dry matter digestibility

Effect of galactooligosaccharides and Bifidobacterium animalis Bb-12 on growth of Lactobacillus amylovorus DSM 16698, microbial community structure, and metabolite production in an in vitro colonic model set up with human or pig microbiota

A validated in vitro model of the large intestine (TIM-2), set up with human or pig faeces, was used to evaluate the impact of potentially probiotic Lactobacillus amylovorus DSM 16698, administered alone (i), in the presence of prebiotic galactooligosaccharides (GOS) (ii), and co-administered with probiotic Bifidobacterium animalis ssp. lactis Bb-12 (Bb-12) (iii) on GOS degradation, microbial growth (L. amylovorus, lactobacilli, bifidobacteria and total bacteria) and metabolite production. High performance anion exchange chromatography revealed that GOS degradation was more pronounced in TIM-2 inoculated with pig faeces than with human faeces. Denaturing gradient gel electrophoresis profiling of PCR-amplified 16S rRNA genes detected a more complex Lactobacillus spp. community in pig faecal material than in human faecal inoculum. According to 16S rRNA gene-targeted qPCR, GOS stimulated the growth of lactobacilli and bifidobacteria in faecal material from both materials. The cumulative production of short chain fatty acids and ammonia was higher (P <0.05) for pig than for human faeces. However, lactate accumulation was higher (P <0.05) in the human model and increased after co-administration with GOS and Bb-12. This study reinforced the notion that differences in microbiota composition between target host organisms need to be considered when animal data are extrapolated to human, as is often done with pre- and probiotic intervention studie