Fecal Organic Acid Concentrations Research Articles

Continuous intake of galacto-oligosaccharides containing syrup contributes to maintaining the health of household dogs by modulating their gut microbiota.

Interest is growing in the relationship of the microbiota and intestinal environment with health in companion animals. Galacto-oligosaccharides (GOS), typical prebiotics, are expected to provide benefits in dogs. Previous studies of GOS in dogs have involved dogs with similar rearing conditions and diets, which may have biased the results. We conducted an open study of 26 healthy dogs kept in households with diverse rearing environments in order to evaluate how the intake of a GOS-containing syrup affects the intestinal microbiota and its metabolites. Each dog was fed 1.2-4.8 g of the GOS-containing syrup (GOS 0.5-2.0 g equivalent) for 8 weeks. Fecal microbiota, fecal concentrations of organic acids and putrefactive products, fecal odor, and serum uremic toxin concentrations were evaluated before intake (0 weeks), during the 8-week intake period (4 and 8 weeks), and 4 weeks after intake (12 weeks). The activity of N-benzoyl-DL-arginine peptidase in dental plaque, which may be associated with periodontal disease, was evaluated at 0 and 8 weeks. Continuous intake of GOS resulted in changes in fecal microbiota, with a particularly marked increase in the abundance of Megamonas, which produces propionic acid. Other findings included a significant increase in the fecal acetic, propionic, and n-butyric acid concentrations. Additionally, significant decreases in fecal odor, fecal phenol concentration, and serum indoxyl sulfate concentration. Intake of GOS was also associated with a significant decrease in N-benzoyl-DL-arginine peptidase activity in dental plaques. These results suggest that continuous intake of GOS may contribute to canine health.

Development of an improved colonization system for human-derived Bifidobacterium longum subsp. longum in conventional mice through the feeding of raffinose or 1-kestose.

How bifidobacteria colonize and survive in the intestine is not fully understood. The administration of bifidobacteria to conventional mice can be used to evaluate their ability to colonize the intestine in the presence of endogenous gut microbiota. However, human-derived bifidobacteria do not readily colonize the intestines of conventional mice, and although colonization by Bifidobacterium breve UCC2003 has been achieved, the viability of such populations requires improvement. Therefore, we aimed to establish a colonization system with human-derived bifidobacteria of high viability in conventional mice using Bifidobacterium longum subsp. longum 105-A. Lactose, raffinose, and 1-kestose were identified as the preferred carbohydrate sources for the growth of this strain in culture. The administration of B. longum 105-A to conventional BALB/c mice fed these carbohydrates showed that diets containing 6% (w/w) raffinose or 1-kestose facilitated colonization with >108 colony-forming units/g feces for 2 weeks. The population of this strain was more stable in the raffinose-fed group than in the 1-kestose-fed group. The ingestion of these prebiotics had a greater impact on the composition of the microbiota than the administration of B. longum 105-A. The ingestion of these prebiotics also increased the fecal concentrations of organic acids, which was indicative of greater intestinal fermentation. Collectively, we established a colonization system for B. longum 105-A with high viability in conventional mice by feeding the mice raffinose or 1-kestose. This system should be useful for elucidation of the mechanisms of colonization and survival of bifidobacteria in the intestines in the presence of the endogenous gut microbiota.

Association between postoperative changes in the gut microbiota and pseudopsia after cardiac surgery: prospective observational study

BackgroundDelirium after cardiac surgery affects mortality, but the mechanism remains unclear. Previous studies have reported gut microbiota are associated with brain activity. Systemic inflammation and antibiotics can damage the gut microbiota after cardiac surgery. We aimed to investigate changes in the gut microbiota and the association between the gut microbiota and delirium after cardiac surgery.MethodsTwenty-one patients who underwent cardiac surgery were enrolled. Microbiota counts and fecal organic acid concentrations were measured in fecal samples harvested before surgery, just after surgery, and before discharge. To quantify the microbiota, we extracted total RNA fractions and examined gut microbiota composition using 16S and 23S rRNA-targeted quantitative-reverse Transcription-PCR. Postoperative delirium, insomnia, and pseudopsia were assessed for 1 week. Postoperative total bacterial counts changed significantly from 10.2 ± 0.2 log10 cells/g of feces to 9.8 ± 0.5 in the first postoperative samples (p = 0.003) and 10.0 ± 0.4 in the samples before discharge (p = 0.039). Fecal pH was 6.9 ± 0.6 before surgery and 7.4 ± 0.7 in the first postoperative samples (p = 0.001). Postoperative Staphylococcus and Pseudomonas counts were significantly higher in patients with postoperative pseudopsia than in patients without pseudopsia (3.2 ± 1.3 vs. 5.4 ± 0.9; p = 0.012 and 1.7 ± 0.8 vs. 4.6 ± 2.7; p = 0.001).ConclusionsTotal bacterial counts were significantly lower after surgery and until discharge. Fecal pH was significantly higher than preoperative levels. Staphylococcus and Pseudomonas counts were significantly higher in patients with postoperative pseudopsia.

B. Infantis EVC001 Metabolites Improve Enterocyte Proliferation in Vitro

Abstract Objectives Bacterial metabolites, including short chain fatty acids (SCFA) are essential for host cells to maintain homeostasis. Previous findings showed exclusively breastfed infants colonized with B. infantis EVC001 have significantly increased fecal organic acid concentrations, specifically lactate and acetate as compared to infants not colonized with B. infantis, we investigated the effect of fecal water (FW) from two distinct populations on enterocyte proliferation and morphology in vitro. Methods FW were derived from fecal samples from infants colonized with B. infantis EVC001 (EVC001) and infants not colonized with B. infantis (controls) were added to adult and premature enterocyte cell lines to assess growth, proliferation and cytotoxicity. Microscopic images were taken to observe morphological differences. Results Intestinal epithelial cells (IECs; Caco-2 and HIEC-6 cells) exposed to EVC001 FW showed significantly increased proliferation shown by ATP expression compared to medium alone and control FW (P < 0.0001). Conversely, significantly decreased lactate dehydrogenase, an indication of decreased membrane integrity, was detected in enterocytes exposed to EVC001 FW compared to controls FW (P < 0.01). Specific bacterial metabolites, lactate and acetate at median physiological concentrations found in EVC001 infant FW significantly increased Caco-2 intestinal integrity measured by transepithelial electrical resistance compared to medium alone (P < 0.01, P < 0.05, respectively), while control levels did not significantly increase proliferation. Furthermore, control FW altered the morphology of enterocytes compared to cells exposed to EVC001 FW or medium alone. Conclusions EVC001 FW and specific bacterial metabolites, lactate and acetate significantly increased enterocyte proliferation compared to control FW and medium alone, while control FW negatively affected cell growth, membrane integrity and cell morphology; suggesting metabolites produced by B. infantis EVC001 promote enterocyte growth and improve intestinal integrity in both adult and premature infants. Funding Sources Evolve Biosystems.

Impact of preoperative fecal short chain fatty acids on postoperative infectious complications in esophageal cancer patients

BackgroundThe intestinal epithelial barrier allows absorption of dietary nutrients and prevents passage of pathogens and toxins into the body. Severe insults have a negative impact on the intestinal environment, which may decrease intestinal barrier function and cause bacterial translocation. Bacterial translocation, which can cause infectious complications, is defined as the passage of microbes from the gastrointestinal tract across the mucosal barrier to extraintestinal sites. The aim of this study was to investigate the correlation between concentrations of preoperative fecal organic acids and the occurrence of postoperative infectious complications in patients with esophageal cancer.MethodsFifty-five patients with esophageal cancer who underwent esophagectomy were enrolled in this study. Perioperative synbiotics were administered to all patients. Perioperative clinical characteristics and concentrations of preoperative fecal organic acids were compared between patients with and without postoperative infectious complications.ResultsPostoperative infectious complications occurred in 10 patients. In patients with complications, the concentrations of acetic acid and propionic acid were significantly lower than in patients without complications (p = 0.044 and 0.032, respectively). The concentration of butyric acid was nonsignificantly lower in patients with complications, while the concentration of lactic acid was nonsignificantly higher. The calculated gap between the concentrations of fecal acetic acid plus propionic acid plus butyric acid minus lactic acid was significantly lower in patients with complications. Multivariate analysis revealed that a low gap between acetic acid plus propionic acid plus butyric acid minus lactic acid was an independent risk factor for postoperative infectious complications (p = 0.027).ConclusionsPreoperative fecal concentrations of organic acids had a clinically important impact on the occurrence of postoperative infectious complications in patients with esophageal cancer. To reduce postoperative infectious complications, it may be useful to modulate the intestinal environment and maintain concentrations of fecal organic acids before surgery.

Bacterial profile of infant feces associated with lactation infectious breasts.

BackgroundMastitis is a common complication in lactating women. However, the diversity of intestinal bacteria in infant exclusively fed infectious milk remains uncharacterized. Our colleagues recently established a method based on 16S and 23S rRNA-targeted reverse transcription–quantitative PCR (RT-qPCR) for detecting bacteria.Materials and methodsIn the present study, the bacteria present in 14 samples of milk and infant feces were characterized using the RT-qPCR method, and concentrations of fecal organic acids were measured during the period of breast massage using HPLC.ResultsStreptococcus agalactiae and Str. parasanguinis were detected in milk from mastitis patients, whereas Str. salivarius and Str. thermophilus were the predominant bacteria in milk from engorged breasts. In feces of breastfed infants, Str. salivarius, Str. thermophiles, and Str. parasanguinis were isolated. Levels of lactate were high in fecal samples, whereas the pH of infant feces stabilized during breast massage. The bacterial diversity of milk from lactation infectious breasts was similar to that in feces of infant fed milk from lactation infectious breasts. Streptococcus species isolated from the feces of breastfed infants are related to oral cavity health.ConclusionThese results suggest that Streptococcus species, which are part of the healthy oral microflora, may play an important role in preserving the intestinal bacterial flora in infants fed infectious milk.

Gut Microbiota Patterns in Obese and Type 2 Diabetes (T2D) Patients from Romanian Black Sea Coast Region

Gut microbiota plays a major role in the process of food absorption and low grade inflammation, two key steps in obesity and diabetes mellitus occurrence. Gut microbiota metabolites, such as short chain fatty acids (SCFA), have an important impact over the metabolic pathways like insulin signalling, incretin production and inflammation. [1-3] We aimed to study the microbiota patterns in obese and T2D patients from Black Sea Coast region, considering the ethnic mixture, environmental and geographical particularities, involving diet or various habits in this area. 100 patients and 100 controls matched by age, gender and ethnicity were studied regarding feaces predominance of Lactobacillus and Bifidobacterium species. We compared the results of microbiota patterns from patients to those obtained in a similar control group of healthy subjects. The standard pour plate 0.05% L-cystine enriched method was used to obtain the bacterial cultures and anaerobic conditions. Morphological and biochemical tests were used to identify the Lactobacillus and Bifidobacterium spp. Fecal organic acid concentrations were explored in frozen samples. The association between bacterial counts/organic acid concentrations and independent variables, including age, diet, ethnicity and other risk factors were calculated using multivariable linear regression analysis. Pearson�s correlation coefficients were calculated to detect associations between fecal bacteria counts/organic acid concentrations and laboratory variables (serum biomarkers, body mass index, age, and severity of obesity/T2D according to international scales). Junk and sweet diets, lack of physical activity and familial aggregation of hypercholesterolemia and diabetes were significantly more often present in our T2D/obese patients than in controls. The bacterial counts of the L. acidophilus, L plantarum and L. reuteri subgroups of Lactobacillus sp were significantly lower among patients with T2D and obesity than in controls. The counting of Bifidobacterium spp revealed a higher presence of B. bifidum in controls than in obese or T2D patients. Diet type (junk food and sweets), BMI (]25) and personal history of metabolic disorders were associated with decreased counts of L acidophilus and increased counts of L. fermentum and B. adolescentis in T2D patients. Ethnicity, metabolic disorders history and junk and sweet diet were associated with low counts of L. acidophilus and L. reuteri and low counts of B. longum. Junk and sweet diet was associated with low counts of B. bifidum. Romanian ethnicity and metabolic disorders were associated with low counts of B. choerinum at obese patients, independent of age or previous antidiabetic treatments. The concentrations of acetic and butyric acids were significantly lower in all patients groups, while the concentrations of valeric acid were significantly higher in patients with untreated T2D and obese patients compared to the controls. Low counts of L. acidophilus and L. reuteri were positively correlated with the increased levels of HbA1c, LDL cholesterol, TG and inflammatory markers such as CRP, ESR and IL-6, no matter of diet, age, ethnicity or metabolic disorders history. Also, low counts of B. bifidum and B. infantis were positively correlated with high levels of CRP, IL-6 and TG. In obese patients, statistic analysis results showed that low counts of L. acidophilus, L. plantarum, L. johnsonii and L. reuteri were positively associated with increased levels of CPR, IL-6 and TG, while low counts of B. bifidum, B infantis and B. breve were positively correlated with higher counts of CPR, LDL cholesterol and TG. Low counts of B. bifidum and B choerinum were positively correlated with low counts of HDL cholesterol in Romanian ethnicity patients and in those with previous metabolic disorders. Low bacterial counts of some particular strains of Lactobacillus spp and Bifidobacterium spp were positively correlated with diet type, BMI, Romanian ethnicity and personal history of metabolic disorders obese and T2D patients from Romanian Black Sea Coast Region.

Gut Microbiota Composition Before and After Use of Proton Pump Inhibitors

BackgroundRecently, problems associated with proton pump inhibitor (PPI) use have begun to surface. PPIs influence the gut microbiota; therefore, PPI use may increase the risk of enteric infections and cause bacterial translocation. In this study, we investigated fecal microbiota composition, fecal organic acid concentrations and pH, and gut bacteria in the blood of the same patients before and after PPI use.MethodsTwenty patients with reflux esophagitis based on endoscopic examination received 8 weeks of treatment with PPIs. To analyze fecal microbiota composition and gut bacteria in blood and organic acid concentrations, 16S and 23S rRNA-targeted quantitative RT-PCR and high-performance liquid chromatography were conducted.ResultsLactobacillus species were significantly increased at both 4 and 8 weeks after PPI treatment compared with bacterial counts before treatment (P = 0.011 and P = 0.002, respectively). Among Lactobacillus spp., counts of the L. gasseri subgroup, L. fermentum, the L. reuteri subgroup, and the L. ruminis subgroup were significantly increased at 4 and 8 weeks after treatment compared with counts before treatment. Streptococcus species were also significantly increased at 4 and 8 weeks after PPI treatment compared with counts before treatment (P < 0.01 and P < 0.001, respectively). There was no significant difference in the total organic acid concentrations before and after PPI treatment. Detection rates of bacteria in blood before and after PPI treatment were 22 and 28%, respectively, with no significant differences.ConclusionsOur quantitative RT-PCR results showed that gut dysbiosis was caused by PPI use, corroborating previous results obtained by metagenomic analysis.

Profile of preoperative fecal organic acids closely predicts the incidence of postoperative infectious complications after major hepatectomy with extrahepatic bile duct resection: Importance of fecal acetic acid plus butyric acid minus lactic acid gap

To investigate the association between preoperative fecal organic acid concentrations and the incidence of postoperative infectious complications in patients undergoing major hepatectomy with extrahepatic bile duct resection for biliary malignancies. The fecal samples of 44 patients were collected before undergoing hepatectomy with bile duct resection for biliary malignancies. The concentrations of fecal organic acids, including acetic acid, butyric acid, and lactic acid, and representative fecal bacteria were measured. The perioperative clinical characteristics and the concentrations of fecal organic acids were compared between patients with and without postoperative infectious complications. Among 44 patients, 13 (30%) developed postoperative infectious complications. Patient age and intraoperative bleeding were significantly greater in patients with postoperative infectious complications compared with those without postoperative infectious complications. The concentrations of fecal acetic acid and butyric acid were significantly less, whereas the concentration of fecal lactic acid tended to be greater in the patients with postoperative infectious complications. The calculated gap between the concentrations of fecal acetic acid plus butyric acid minus lactic acid gap was less in the patients with postoperative infectious complications (median 43.5 vs 76.1μmol/g of feces, P=.011). Multivariate analysis revealed that an acetic acid plus butyric acid minus lactic acid gap <60μmol/g was an independent risk factor for postoperative infectious complications with an odds ratio of 15.6; 95% confidence interval 1.8-384.1. The preoperative fecal organic acid profile (especially low acetic acid, low butyric acid, and high lactic acid) had a clinically important impact on the incidence of postoperative infectious complications in patients undergoing major hepatectomy with extrahepatic bile duct resection.

Gut dysbiosis is associated with metabolism and systemic inflammation in patients with ischemic stroke.

The role of metabolic diseases in ischemic stroke has become a primary concern in both research and clinical practice. Increasing evidence suggests that dysbiosis is associated with metabolic diseases. The aim of this study was to investigate whether the gut microbiota, as well as concentrations of organic acids, the major products of dietary fiber fermentation by the gut microbiota, are altered in patients with ischemic stroke, and to examine the association between these changes and host metabolism and inflammation. We analyzed the composition of the fecal gut microbiota and the concentrations of fecal organic acids in 41 ischemic stroke patients and 40 control subjects via 16S and 23S rRNA-targeted quantitative reverse transcription (qRT)-PCR and high-performance liquid chromatography analyses, respectively. Multivariable linear regression analysis was subsequently performed to evaluate the relationships between ischemic stroke and bacterial counts and organic acid concentrations. Correlations between bioclinical markers and bacterial counts and organic acids concentrations were also evaluated. Although only the bacterial counts of Lactobacillus ruminis were significantly higher in stroke patients compared to controls, multivariable analysis showed that ischemic stroke was independently associated with increased bacterial counts of Atopobium cluster and Lactobacillus ruminis, and decreased numbers of Lactobacillus sakei subgroup, independent of age, hypertension, and type 2 diabetes. Changes in the prevalence of Lactobacillus ruminis were positively correlated with serum interleukin-6 levels. In addition, ischemic stroke was associated with decreased and increased concentrations of acetic acid and valeric acid, respectively. Meanwhile, changes in acetic acid concentrations were negatively correlated with the levels of glycated hemoglobin and low-density lipoprotein cholesterol, whereas changes in valeric acid concentrations were positively correlated with the level of high sensitivity C-reactive protein and with white blood cell counts. Together, our findings suggest that gut dysbiosis in patients with ischemic stroke is associated with host metabolism and inflammation.

Intestinal Microbiota Profiles of Healthy Pre-School and School-Age Children and Effects of Probiotic Supplementation

Objectives: This study aims to establish the baseline profile of intestinal microbiota in pre-school and school-age Japanese children and to investigate the effects of a probiotic on the microbiota. Methods: We analyzed the intestinal microbiota and investigated the effects (before, during and after the ingestion period) on intestinal microbiota and the environment of 6 months of daily ingestion of a probiotic (Lactobacillus casei strain Shirota (LcS)-fermented milk). Results: We performed an open trial in 23 children (14 boys, 9 girls; age 7.7 ± 2.4 years (mean ± SD); BMI 19.6 ± 4.6). The composition of intestinal microbiota of healthy pre-school and school-age children resembled that of adults. During probiotic supplementation, the population levels of Bifidobacterium and total Lactobacillus increased significantly, while those of Enterobacteriaceae, Staphylococcus and Clostridium perfringens decreased significantly. A significant increase in fecal concentrations of organic acids and also a decrease in fecal pH were observed during the ingestion period. However, the patterns of fecal microbiota and intestinal environment were found to revert to the baseline levels (i.e. before ingestion) within 6 months following the cessation of probiotic intake. Conclusion: Regular intake of an LcS-containing probiotic product may modify the gut microbiota composition and intestinal environment in pre-school and school-age children while maintaining the homeostasis of the microbiota.

Effects of Oral Administration of Chitin Nanofiber on Plasma Metabolites and Gut Microorganisms.

The aim of this study was to examine the effects of oral administration of chitin nanofibers (CNFs) and surface-deacetylated (SDA) CNFs on plasma metabolites using metabolome analysis. Furthermore, we determined the changes in gut microbiota and fecal organic acid concentrations following oral administrations of CNFs and SDACNFs. Healthy female mice (six-week-old) were fed a normal diet and administered tap water with 0.1% (v/v) CNFs or SDACNFs for 28 days. Oral administration of CNFs increased plasma levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP), and serotonin (5-hydroxytryptamine, 5-HT). Oral administration of SDACNFs affected the metabolisms of acyl-carnitines and fatty acids. The fecal organic level analysis indicated that oral administration of CNFs stimulated and activated the functions of microbiota. These results indicate that oral administration of CNFs increases plasma levels of ATP and 5-HT via activation of gut microbiota.

Effects of the enteral administration of Bifidobacterium breve on patients undergoing chemotherapy for pediatric malignancies

Probiotics are expected to be effective in prophylaxis of infection in cancer patient, since infections in neutropenics are mainly caused by endogenous flora through the intestinal mucosa. However, the experience with the use of probiotics in immunocompromised patients is limited, and precise fecal bacteria analysis has not been reported. The aim of the study was to evaluate the effects of the enteral administration of the probiotic, Bifidobacterium breve strain Yakult, on its ability to prevent infection, fecal micro flora, and intestinal environments in cancer patients on chemotherapy. A placebo-controlled trial was performed at Juntendo University Hospital. Patients with malignancies admitted for chemotherapy (n = 42) were randomized into two groups receiving probiotic or placebo. The effects on infectious complications, natural killer cells, fecal micro flora, fecal organic acid concentrations, and fecal pH were studied. The frequency of fever and the use of intravenous antibiotics were lower in the probiotic group than the placebo group. The probiotic administration enhanced the habitation of anaerobes. Disruption of the intestinal microbiota after chemotherapy such as the increase in the population levels of Enterobacteriaceae was observed at more pronounced manner in the placebo group in comparison to the probiotic group. The concentrations of total organic acids were maintained most of the time at the normal level, which constantly maintained the pH below 7.0 only in the probiotic group. These data, although based on a limited number of patients and samples, suggest that administration of B. breve strain Yakult could be an effective approach for achieving clinical benefits in immunocompromised hosts by improving their intestinal environments.

Lactobacillus plantarum 299v Enhances the Concentrations of Fecal Short-Chain Fatty Acids in Patients with Recurrent Clostridium difficile-Associated Diarrhea

Our objective was to document how intake of Lactobacillus plantarum 299v affects the concentrations of fecal organic acids during and after metronidazole treatment in 19 patients with recurrent Clostridium difficile-associated diarrhea. Fecal samples were analyzed by gas-liquid chromatography. After intake of metronidazole a significant decrease in total short-chain fatty acids was seen in the placebo group (from 77.1 to 45.5 micromol/g; P=0.028) but not in the Lactobacillus group (79.8-60.4 micromol/g). In addition, a statistically significant difference between treatment groups was noted for butyrate (5.6-1.2 micromol/g in the placebo group vs. 7.6-5.6 micromol/g in the Lactobacillus group; P=0.047). At the end of the study and after cessation of placebo or Lactobacillus, the total short-chain fatty acids rose to the same levels as before antibiotic treatment in the placebo group. Both treatment groups showed a significant decrease in concentrations of succinate at the end of the study in comparison to the time when metronidazole intake was stopped (6.3-1.5 micromol/g in the placebo group versus 9.3-0.9 micromol/g in the Lactobacillus group; P=0.028). The present study of fecal samples from a clinical trial is the first to demonstrate that administration of Lactobacillus plantarum 299v reduces the negative effects of an antibiotic on colonic fermentation. The intake of this probiotic strain may thereby provide an additional benefit for patients with recurrent Clostridium difficile-associated diarrhea.

Perioperative Synbiotic Treatment to Prevent Postoperative Infectious Complications in Biliary Cancer Surgery

Use of synbiotics has been reported to benefit human health, but clinical value in surgical patients remains unclear. To investigate the effect of perioperative oral administration of synbiotics upon intestinal barrier function, immune responses, systemic inflammatory responses, microflora, and surgical outcome in patients undergoing high-risk hepatobiliary resection. Patients with biliary cancer involving the hepatic hilus (n = 101) were randomized before hepatectomy, into a group receiving postoperative enteral feeding with synbiotics (group A); or another receiving preoperative plus postoperative synbiotics (group B). Lactulose-mannitol (L/M) ratio, serum diamine oxidase (DAO) activity, natural killer (NK) cell activity, interleukin-6 (IL-6), fecal microflora, and fecal organic acid concentrations were determined before and after hepatectomy. Postoperative infectious complications were recorded. Of 101 patients, 81 completed the trial. Preoperative and postoperative changes in L/M ratio and DAO activity were similar between groups. Preoperatively in group B, NK activity, and lymphocyte counts increased, while IL-6 decreased significantly (P < 0.05). Postoperative serum IL-6, white blood cell counts, and C-reactive protein in group B were significantly lower than in group A (P < 0.05). During the preoperative period, numbers of Bifidobacterium colonies cultured from and total organic acid concentrations measured in feces increased significantly in group B (P < 0.05). Postoperative concentrations of total organic acids and acetic acid in feces were significantly higher in group B than in group A (P < 0.05). Incidence of postoperative infectious complications was 30.0% (12 of 40) in group A and 12.1% (5 of 41) in group B (P < 0.05). Preoperative oral administration of synbiotics can enhance immune responses, attenuate systemic postoperative inflammatory responses, and improve intestinal microbial environment. These beneficial effects likely reduce postoperative infectious complications after hepatobiliary resection for biliary tract cancer.

Effects of lactulose on intestinal bacterial flora and fecal organic acids in patients with liver cirrhosis

To evaluate the effects of oral lactulose on fecal bacterial flora, we measured fecal bacterial counts and organic acid concentration before and 2 weeks after lactulose administration in patients with liver cirrhosis. Lactulose administration resulted in increases in the total anaerobic bacterial count and in the proportion of Bifidobacterium, and a decrease in that of Bacteroides in the flora. Fecal concentrations of organic acids remained unaltered following lactulose administration. These results suggest that lactulose administration suppresses the proportion of urease-forming bacteria independent of fecal organic acid levels.