Absence of adverse events in healthy individuals using probiotics--analysis of six randomised studies by one study group.

Consumption of live bacteria as probiotic supplements is increasing. There is, however, a lack of information on the safety of ingested probiotics. The main objective of this study was to investigate the adverse events (AEs) of specific probiotics (Lactobacillus rhamnosus GG (LGG) alone or LGG in combination with L. rhamnosus Lc705, Propionibacterium freudenreichii JS, Bifidobacterium lactis BB12, or Bifidobacterium breve 99) studied in six of our study groups' clinical trials, by analysing individual participant data. A secondary objective was to study AEs associated with the consumed probiotic species and mixtures in three specific categories; 'gastrointestinal disorders', 'respiratory, thoracic and mediastinal disorders' and 'infections and infestations'. Six randomised, double-blind, placebo-controlled clinical studies by our study group were included in this AE analysis (study population n=1,909). All AE data were classified according to the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) v4.0. From the 26 CTCAE System Organ Classes, we identified AEs in 20 classes among 1,909 subjects. Probiotic ingestion did not result in statistically significant differences in AEs in different groups, when compared to placebo. A subgroup analysis of gastrointestinal, respiratory, thoracic and mediastinal disorders, infections and infestations, found no differences between the intervention groups or for different probiotic combinations (risk ratio (RR) = 0.97, 95% confidence interval (CI): 0.93-1.02, P=0.30; RR=0.99, 95% CI: 0.97-1.01, P=0.35; RR=0.99, 95% CI: 0.93-1.06, P=0.62, respectively). As a conclusion, ingestion of probiotic supplementations containing LGG alone, or LGG in combination with L. rhamnosus Lc705, P. freudenreichii JS, B. breve 99, or B. lactis BB12 did not seem to cause AEs in young and elderly subjects in this analysis.

Synbiotic effects of lactitol and Lactobacillus acidophilus NCFM™ in a semi-continuous colon fermentation model.

The effects of Lactobacillus acidophilus NCFM™, lactitol, and the combination of lactitol and L. acidophilus NCFM™ were studied with a semi-continuous colon fermentation simulation; consisting of compartments mimicking, ascending, transverse, descending and sigmoid colon and their conditions with faecal inoculation. L. acidophilus NCFM™ was detected throughout the colon simulator. Lactitol was utilised early on by the microbes in the proximal part of the simulator. Lactitol increased the total numbers of microbes and bifidobacteria, and decreased clostridia cluster IV, while L. acidophilus NCFM™ alone decreased the numbers of clostridia cluster XIV. Combination treatment increased the numbers of bifidobacteria. Furthermore, concentrations of acetic acid, butyric acid and the sum of total short-chain fatty acids were increased by both lactitol-including treatments. The treatment with L. acidophilus NCFM™ alone increased the concentration of propionic acid and butyric acid. L. acidophilus NCFM™ tended to increase the total concentrations of biogenic amines, while lactitol suppressed production of biogenic amines also in the presence of L. acidophilus NCFM™. True synergistic effects are suggested in stimulation of the production of butyrate, an important microbial metabolite for colon health. In conclusion, lactitol as well as the combination of lactitol and L. acidophilus NCFM™ were found to exhibit complementary beneficial effects on the colon microbial composition and activity.

The effects of polydextrose and xylitol on microbial community and activity in a 4-stage colon simulator.

This study focused on the effects of candidate prebiotics polydextrose (PDX) and xylitol on the microbial community and its metabolic activity in a colon simulator. A semicontinuous, anaerobic culture system was used with 4 vessels mimicking the conditions in the human large intestine from proximal to distal colon. Bacterial inocula for the independent simulations were obtained from fecal samples of different donors. Synthetic medium, mimicking the contents of the small intestine, containing either 2% of the prebiotic candidate or no added carbohydrates as a control, was fed to the system. After 48 h of simulation samples were collected and analyzed. A sustained degradation of polydextrose throughout the colon model and a more rapid degradation of xylitol were observed. The fermentation of both compounds was characterized by a significantly increased production of short-chain fatty acids (SCFA). Polydextrose increased the concentrations of all SCFA, especially acetate and propionate, and xylitol especially the concentration of butyrate. Branched-chain fatty acids (BCFA) levels decreased significantly as a result of polydextrose and xylitol supplementation, whereas biogenic amine levels remained mostly unchanged. Thus, a beneficial shift in the metabolic patterns of the colon microbes was measured with both of the tested products. These in vitro studies provide evidence to the prebiotic characteristics of polydextrose; also, further beneficial properties of xylitol were demonstrated in the colon model.

Enzymes as feed additive to aid in responses against Eimeria species in coccidia-vaccinated broilers fed corn-soybean meal diets with different protein levels.

This research aimed to evaluate the effects of adding a combination of exogenous enzymes to starter diets varying in protein content and fed to broilers vaccinated at day of hatch with live oocysts and then challenged with mixed Eimeria spp. Five hundred four 1-d-old male Cobb-500 chickens were distributed in 72 cages. The design consisted of 12 treatments. Three anticoccidial control programs [ionophore (IO), coccidian vaccine (COV), and coccidia-vaccine + enzymes (COV + EC)] were evaluated under 3 CP levels (19, 21, and 23%), and 3 unmedicated-uninfected (UU) negative controls were included for each one of the protein levels. All chickens except those in unmedicated-uninfected negative controls were infected at 17 d of age with a mixed oral inoculum of Eimeria acervulina, Eimeria maxima, and Eimeria tenella. Live performance, lesion scores, oocyst counts, and samples for gut microflora profiles were evaluated 7 d postinfection. Ileal digestibility of amino acids (IDAA) was determined 8 d postinfection. Microbial communities (MC) were analyzed by G + C%, microbial numbers were counted by flow cytometry, and IgA concentrations were measured by ELISA. The lowest CP diets had poorer (P < or = 0.001) BW gain and feed conversion ratio in the preinfection period. Coccidia-vaccinated broilers had lower performance than the ones fed ionophore diets during pre- and postchallenge periods. Intestinal lesion scores were affected (P < or = 0.05) by anticoccidial control programs, but responses changed according to gut section. Feed additives or vaccination had no effect (P > or = 0.05) on IDAA, and diets with 23% CP had the lowest (P < or = 0.001) IDAA. Coccidial infection had no effect on MC numbers in the ileum but reduced MC numbers in ceca and suppressed ileal IgA production. The COV + EC treatment modulated MC during mixed coccidiosis infection but did not significantly improve chicken performance. Results indicated that feed enzymes may be used to modulate the gut microflora of cocci-vaccinated broiler chickens.