Higher Butyric Acid Concentrations Research Articles

The periodontal pathogen Porphyromonas gingivalis induces the Epstein–Barr virus lytic switch transactivator ZEBRA by histone modification

Epstein–Barr virus (EBV) is a ubiquitous human herpesvirus that usually results in latent infection of B cells. The EBV BZLF1 gene product ZEBRA is a master regulator of the transition from latency to the lytic replication cycle. In the latent state, hypoacetylation of histone proteins in the BZLF1 promoter by histone deacetylases (HDACs) is primarily involved in maintaining EBV latency. Although the mechanism that regulates the switch between latency and lytic replication has been a central research focus in EBV infection, the causal link between HDAC inhibition and the disruption of viral latency is not well understood. Periodontal disease is a complex chronic inflammatory disease caused by subgingival infection with oral anaerobic bacteria, typically Porphyromonas gingivalis. Periodontal disease occurs worldwide and is among the most prevalent microbial diseases in humans. In this study, we examined the biological effect of P. gingivalis infection on EBV reactivation and found that P. gingivalis induced expression of ZEBRA. This activity was associated with supernatant from bacterial culture, but not with other bacterial components such as lipopolysaccharide or fimbriae. We demonstrated that culture supernatant from P. gingivalis, which contained high concentrations of butyric acid, inhibited HDACs, thus increasing histone acetylation and the transcriptional activity of the BZLF1 gene. Chromatin immunoprecipitation assays revealed that HDACs were present in the BZLF1 promoter during latent state and that they were dissociated from the promoter concomitantly with the association of acetylated histone H3, upon stimulation by culture supernatant from P. gingivalis. Thus, P. gingivalis induced EBV reactivation via chromatin modification, and butyric acid—a bacterial metabolite—was responsible for this effect. These findings suggest that periodontal disease is a risk factor for EBV reactivation in infected individuals and might therefore contribute to progression of EBV-related diseases.

Influence of dietary blueberry and broccoli on cecal microbiota activity and colon morphology in mdr1a−/− mice, a model of inflammatory bowel diseases

ObjectiveEnteric microbiota has been shown to be associated with various pathological conditions such as inflammatory bowel disease (IBD). This study aimed to determine the anti-inflammatory colonic effects of blueberries and broccoli in mdr1a−/− mice (IBD mouse model) through modification of microbiota composition in the gastrointestinal tract. MethodsThe mdr1a−/− mice were fed either a control diet or the control diet supplemented with either 10% blueberry or broccoli for 21 wk. We investigated the influence of these diets on cecal microbiota and organic acids, colon morphology, and bacterial translocation to mesenteric lymph nodes. ResultsIn comparison to mice fed the control diet, blueberry and broccoli supplementation altered cecum microbiota similarly with the exception of Faecalibacterium prausnitzii, which was found to be significantly lower in broccoli-fed mice. High concentrations of butyric acid and low concentrations of succinic acid were observed in the cecum of broccoli-fed mice. Blueberry- and broccoli-supplemented diets increased colon crypt size and the number of goblet cells per crypt. Only the broccoli-supplemented diet significantly lowered colonic inflammation compared to mice fed the control diet. Translocation of total microbes to mesenteric lymph nodes was lower in broccoli-fed mice compared to blueberry and control diet groups. ConclusionDietary blueberries and/or broccoli altered the composition and metabolism of the cecal microbiota and colon morphology. Overall, these results warrant further investigation through clinical studies to establish whether the consumption of blueberries and/or broccoli is able to alter the composition and metabolism of large intestine microbiota and promote colon health in humans.

Efficient production of butyric acid from Jerusalem artichoke by immobilized Clostridium tyrobutyricum in a fibrous-bed bioreactor

Butyric acid is an important specialty chemical with wide industrial applications. The feasible large-scale fermentation for the economical production of butyric acid requires low-cost substrate and efficient process. In the present study, butyric acid production by immobilized Clostridium tyrobutyricum was successfully performed in a fibrous-bed bioreactor using Jerusalem artichoke as the substrate. Repeated-batch fermentation was carried out to produce butyric acid with a high butyrate yield (0.44g/g), high productivity (2.75g/L/h) and a butyrate concentration of 27.5g/L. Furthermore, fed-batch fermentation using sulfuric acid pretreated Jerusalem artichoke hydrolysate resulted in a high butyric acid concentration of 60.4g/L, with the yield of 0.38g/g and the selectivity of ∼85.1 (85.1g butyric acid/g acetic acid). Thus, the production of butyric acid from Jerusalem artichoke on a commercial scale could be achieved based on the system developed in this work.

Effects of whey and molasses as silage additives on potato hash silage quality and growth performance of lambs

The aim of the study was to determine the effect of whey or molasses on the fermentation quality when added to potato hash silage. In addition, lamb performance, digestibility and feed intake of diets containing potato hash silage were compared with a diet containing maize silage (MSd). Potato hash silage (treated with no additive, or whey, or molasses) and MS were produced in 210 L drums for 90 days and the fermentation quality of the silages was determined thereafter. Diets were formulated and fed ad libitum to 32 South African Dorper lambs (23.5 ± 0.873 kg live weight) for 63 days. A digestibility study was conducted during the last week of the study. The untreated potato hash silage (UPHS) was poorly fermented as indicated by higher concentrations of butyric acid, ammonia-N and pH compared to the other silages. Higher dry matter intake (DMI) and daily weight gains (218 and 250 g/d) were obtained with MSd and molasses treated potato hash silage diet (MPHSd) compared to the other diets. Nutrient digestibility was lower in the UPHS diet compared to the other dietary treatments. It was concluded that the fermentation quality of potato hash was improved with the addition of whey and molasses. Furthermore, growth performance was higher with the MSd and MPHSd than of the other treatments, suggesting that MPHSd can safely replace MSd in a lamb diet at a dietary inclusion level of 20% without any adverse effect on animal performance.Keywords: Digestibility, dry matter, fermentation, intake, maize silage

Effect of stage of growth on the chemical composition, nutritive value and ensilability of whole-crop barley

Chemical composition, nutritive value and ensilability of whole-crop barley as a supplementary feed for dairy cows was investigated using a range of maturities of barley (seed coat ripe—GS 69, early dough stage—GS 82, soft dough—GS 87 and grain ripe—GS 90) in small scale silos. The ensiling experiment was based on a complete randomised design with three replicate silos per harvest date. Twelve 0.225 m 3 plastic silo (were used in the experiment and silo were sampled on opening for chemical composition and nutritive value. The fermentation process reduced the concentrations of water-soluble carbohydrate in the ensiled forage compared to the fresh forage. The proportion of residual WSC in silage did however increase with increasing crop maturity (0.051, 0.077, 0.167 and 0.560 of WSC retained in the silage after the process of fermentation from forages cut at GS 69, 82, 87 and 90 respectively). Silages that were made from forage cut at the most mature stage of growth had a substantially lower production (P<0.001) of total fermentation acids (38.9 g/kg DM for GS 90) compared to those made from the least mature forage (203.4 g/kg DM for GS 69). The pH and concentrations of the various fermentation acids for silages made with the least mature forage (GS 69) were typical of acetic acid dominated fermentation. These silages contained little or no butyric acid and had a pH of 4.5 and contained high concentrations of ammonia-N (186 g/kg total N). Silages produced from forages cut at growth stage 82 were similar to those conserved from immature forages, having acetic acid dominated fermentation (lactic acid to acetic acid ratio of 1:1.22), relatively high pH (4.85) and high concentrations of ammonia-N (141 g/kg total N). These silages differed from those made from the most immature forage insofar that they contained high concentrations of butyric acid (50.5 g/kg DM). The processes of fermentation were affected by the stage of growth of the forage at ensiling and hence the economics of silage production. If the forage was too immature at ensiling, the yield of crop would be compromised but the silage produced may have moderate to high nutritive value and reasonable aerobic stability during the feed out phase. If the whole-crop forage was grown as a crop to secure high levels of supplementary feed from an alternative forage source (other than grass), the trade-off between yield, nutritive value and losses of feed immediately after silo opening would suggest the crop should be harvested between 350 and 450 g DM/kg dry matter.

Reactivation of Latent HIV-1 Infection by the Periodontopathic Bacterium Porphyromonas gingivalis Involves Histone Modification

Latently infected cells harbor the HIV-1 proviral DNA genome primarily integrated into heterochromatin, allowing the persistence of transcriptionally silent proviruses. Hypoacetylation of histone proteins by histone deacetylases (HDAC) is involved in the maintenance of HIV-1 latency by repressing viral transcription. In addition, periodontal diseases, caused by polymicrobial subgingival bacteria including Porphyromonas gingivalis, are among the most prevalent infections of mankind. Here we demonstrate the effects of P. gingivalis on HIV-1 replication. This activity could be ascribable to the bacterial culture supernatant but not to other bacterial components such as fimbriae or LPS. We found that this HIV-1-inducing activity was recovered in the lower molecular mass (<3 kDa) fraction of the culture supernatant. We also demonstrated that P. gingivalis produces high concentrations of butyric acid, acting as a potent inhibitor of HDACs and causing histone acetylation. Chromatin immunoprecipitation assays revealed that the corepressor complex containing HDAC1 and AP-4 was dissociated from the HIV-1 long terminal repeat promoter upon stimulation with bacterial culture supernatant concomitantly with the association of acetylated histone and RNA polymerase II. We thus found that P. gingivalis could induce HIV-1 reactivation via chromatin modification and that butyric acid, one of the bacterial metabolites, is responsible for this effect. These results suggest that periodontal diseases could act as a risk factor for HIV-1 reactivation in infected individuals and might contribute to the systemic dissemination of the virus.

Effect of potassium diformate on growth performance and gut microbiota in broiler chickens challenged with necrotic enteritis

1. The effect of potassium diformate (KDF) on mortality, growth performance, microbial populations, pH and short chain fatty acid concentrations in the intestinal tract of broiler chickens challenged with necrotic enteritis was investigated. 2. An experiment with 1050 Cobb male broiler chickens was conducted from 1 to 35 d of age. There were 7 treatment groups: (1) unchallenged negative control, (2) unchallenged KDF (4·50 g/kg feed), (3) challenged negative control, (4) challenged positive control (100 ppm monensin and 45 ppm Zn-bacitracin), and (5) to (7) challenged KDF (inclusion rate 2·25, 4·50 and 6·75 g/kg feed, respectively). 3. The necrotic enteritis challenge caused significant growth depression except in the challenged positive control group. Inclusion of KDF in feed had no significant effect on weight gain or feed conversion ratio, neither under challenged nor unchallenged conditions. Necrotic-enteritis-related mortalities were reduced in response to the positive control feed and KDF at 2·25 and 4·50 g/kg rates, but with no effect at the 6·75 g/kg rate. 4. There was no effect of KDF on Clostridium perfringens numbers in jejunum during the necrotic enteritis challenge (d 15). Post challenge (d 35), 4·5 g/kg KDF reduced the number of C. perfringens and Enterobacteria in jejunum compared with the negative control group. 5. Intestinal pH was not affected by adding KDF to the feed. The challenge reduced jejunum pH compared with the unchallenged treatment groups and challenged positive control group. 6. Chickens fed the KDF diets had detectable concentrations of formic acid in the jejunum. There was a tendency towards higher concentrations of acetic acid and lactic acid in the small intestine of unchallenged birds, whereas challenged birds had higher concentrations of butyric acid in the caeca. 7. It is concluded that KDF holds promise as an agent to control necrotic enteritis in broiler chickens and it may be possible to enhance the efficacy of KDF by manipulating dietary properties that may influence the dissociation kinetics of KDF in the gut.

Effect of ensiling field bean, field pea and common vetch in different proportions with whole‐crop wheat using formic acid or an inoculant on fermentation characteristics

AbstractWhole‐crop field bean (FB), field pea (FP) and common vetch (CV) [155, 213 and 238 g dry matter (DM) kg−1] were ensiled in 1·5 L laboratory silos with whole‐crop wheat as mixtures of 0, 0·25, 0·50, 0·75 and 1·00 of fresh weight (FW). Silages were ensiled (i) without additive, and (ii) with formic acid (FA) (4 L t−1) or (iii) an inoculant (Lactobacillus plantarum, 106 colony‐forming units g−1 FW) as additives. The concentrations of water‐soluble carbohydrates in herbage of whole‐crop FB, FP, CV and wheat were 93, 157, 67 and 114 g kg−1 DM and the buffering capacities were 588, 710, 755 and 429 mEq kg−1 DM respectively. Field bean and FP silages were mainly well preserved with low pH values and moderate fermentation losses, except for FB‐only silage without additive which had a high butyric acid concentration. Common vetch silages had higher pH values and were less well fermented compared to the silages of the other legumes. For all legumes, FA reduced ammonia‐N concentrations more effectively compared to other additive treatments. In conclusion, in FB and FP silages the use of FA or an inoculant, as additives, ensured good preservation up to a proportion of legume in the herbage of 0·75. With all legume silages, and with those containing CV, only FA, as an additive, adequately restricted protein breakdown.

Short‐chain fatty acid content in the hindgut of rats fed various composite foods and commercial dietary fibre fractions from similar sources

AbstractThe fermentability of indigestible carbohydrates and content of short‐chain fatty acids along the hindgut of rats were investigated using plant materials of importance in the Swedish diet (instant potato powder, apples and oat flakes). Results with the composite food products were compared with commercial fibre fractions obtained from similar sources, ie potato fibre, apple pectin and β‐glucan‐enriched oat fibre. The materials were incorporated into diets yielding a concentration of 60 or 70 g kg−1 indigestible carbohydrates. The fermentability of indigestible carbohydrates was high with all diets, between 79 and 90%. All substrates except the pure apple pectin generated intermediate to high proportions of butyric acid in the caecum (15–22 vs 8%). The potato products gave high concentrations of butyric acid in the distal colon. The potato powder, ie the diet with the highest content of resistant starch (22 g kg−1), also gave the highest proportion of butyric acid in the distal colon (19%), which was higher than the proportion in the caecum with the same substrate (15%) (P &lt; 0.005). The composite foods promoted a higher proportion of butyric acid in the distal colon as compared with the commercial fibre fractions (P &lt; 0.05).© 2002 Society of Chemical Industry

Chemical attributes characterizing sticky post-mortem ageing in beef

Reports in literature on post-mortem sticky ageing are rare and data about chemical metabolites that occur particularly during sticky ageing are partly contradictory. In the present study different chemicals (pH, NH 3, TVB-N, H 2S, R value, IMP, pyruvate and various volatile acids such as lactic acid, acetic acid, butyric acid, uric acid and pyroglutamic acid) were tested for their suitability to serve as parameters to characterize sticky post-mortem ageing in beef muscle samples. Results show that a high butyric acid concentration (0.46 μMol g −1) seems to be typical for sticky post-mortem ageing in beef. A distinction from onset of spoilage is possible due to the high butyric acid concentration, a low ammonia content (10.5 mg 100 g −1) and a low pH value. From meat with normal ageing it can be differentiated by sensory, colour, smell, consistency, a high butyric and pyroglutamic acid content and a low IMP concentration (0.04 μMol g −1).

Methane Potential of Food Waste and Anaerobic Toxicity of Leachate Produced During Food Waste Decomposition

The objective of this study was to characterize the anaerobic biodegradation of food waste, including its methane potential and the anaerobic toxicity of leachate associated with food waste decomposition. Biodegradation experiments were conducted in 2.2- litre reactors and were seeded with well-decomposed refuse. Despite pH neut ralization, reactors seeded with 30% old refuse failed to undergo methanogenesis. Food waste in a second set of reactors, containing 70% seed, produced 300.7 ml CH4 dry g-1. Leachate toxicity was evaluated by a modified anaerobic toxicity assay (ATA). The results of ATAs were typically consistent with the methane production behavior of the reactors. However, the toxicity observed in the ATA test could not be simulated with synthetic leachate containing high concentrations of carboxylic acids and sodium. Tests with 20, 5, 15 and 12 g 1 ' of acetate, propionate, butyrate and sodium, respectively, suggested that high concentrations of butyric acid and sodium inhibited the onset of methane production but that refuse micro-organisms could acchmatize to these concentrations within 5-10 days. The refuse ecosystem was shown to tolerate higher concentrations of undissociated carboxylic acids than previously reported for anaerobic digesters. © 1997 ISWA

METHANE POTENTIAL OF FOOD WASTE AND ANAEROBIC TOXICITY OF LEACHATE PRODUCED DURING FOOD WASTE DECOMPOSITION

The objective of this study was to characterize the anaerobic biodegradation of food waste, including its methane potential and the anaerobic toxicity of leachate associated with food waste decomposition. Biodegradation experiments were conducted in 2.2-litre reactors and were seeded with well-decomposed refuse. Despite pH neutralization, reactors seeded with 30% old refuse failed to undergo methanogenesis. Food waste in a second set of reactors, containing 70% seed, produced 300.7 ml CH4dry g−1. Leachate toxicity was evaluated by a modified anaerobic toxicity assay (ATA). The results of ATAs were typically consistent with the methane production behavior of the reactors. However, the toxicity observed in the ATA test could not be simulated with synthetic leachate containing high concentrations of carboxylic acids and sodium. Tests with 20, 5, 15 and 12 g l−1of acetate, propionate, butyrate and sodium, respectively, suggested that high concentrations of butyric acid and sodium inhibited the onset of methane production but that refuse micro-organisms could acclimatize to these concentrations within 5–10 days. The refuse ecosystem was shown to tolerate higher concentrations of undissociated carboxylic acids than previously reported for anaerobic digesters.

Preservation of crab or shrimp waste as silage for cattle

Five experiments were conducted to either ferment fresh shrimp or crab waste with molasses, molasses and bacterial inoculant, or to preserve it with salt. Experiment 1 was a 4 × 2 factorial arrangement. Crab waste was combined with 0, 5, 10, or 15% liquid molasses, and stored in mini-silos (15 l) with or without lids for 14 days. The addition of molasses slightly decreased pH and offensive odors; mini-silo temperatures without lids were higher than those with lids. Experiment 2 was a 5 × 2 factorial arrangement designed to enhance fermentation. Fresh shrimp waste was combined with 0, 10, 15, 20, or 25% dry molasses and 0 or 1.0 × 10 8 colony forming bacteria/g inoculant and ensiled for six days. As the level of molasses increased, dry matter and lactic acid increased but, the pH, crude protein, ammonia acetic, butyric, and propionic acid concentrations decreased. Significant molasses by inoculant interactions occurred which were highly variable for each acid. Evidence of fermentation was supported by production of lactic acid at all levels of molasses. The pH decreased from 7.7 in the untreated waste to an average of 7.4 for the 10, 15 and 20% molasses treated wastes to 6.8 in the 25% molasses treated waste. The high pH was an indication that the waste may be unstable with longer storage (> 6 days). Therefore, in Experiment 3, designed as a 2 × 2 factorial arrangement, shrimp waste treated with 15 and 20% molasses, with or without inoculant was ensiled for 21 days to test stability. By day 21, shrimp waste had deteriorated as indicated by a mean pH of 7.5, low lactic acid, and high butyric acid concentration, an unacceptable odor, and the presence of mold on the surface of the samples. In Experiments 4 and 5, shrimp or crab waste was combined with salt at 0, 2.5, 5.0, 7.5, 10.0, and 12.5%. Increasing levels of salt decreased crude protein percent, ammonia concentration, and lactic and volatile fatty acids while increasing the pH and improving the acceptability of the odors in both the shrimp and crab wastes. Treatment of crustacean waste with 7.5% or greater salt was more effective at preserving crude protein and minimizing odor than either dry or liquid molasses.

Influence of sulfates and operational parameters on volatile fatty acids concentration profile in acidogenic phase

Anaerobic treatment of distillery wastewaters containing high sulfate concentrations was carried out on a two-phase process. The acidogenic phase was operated so as to produce the more favourable intermediates for methanogenic bacteria coupled with maximum sulfate removal. Sulfate removal was directly affected by pH and dilution rate (D). The maximum sulfate removal and acetic acid production was achieved at pH 6.6 and D=0.035 h−1. A linear relationship between acetic acid produced and sulfate removal was observed, indicating that acetic acid was mainly produced by sulfate reducing bacteria with important operational advantages. Higher concentrations of butyric acid were obtained at low pH values and high dilution rates.

Branhamella catarrhalis. New methods of bacterial diagnosis.

A total of 176 strains identified as Branhamella catarrhalis were isolated from various clinical specimens, mainly sputum (71), pharynx (49), eye (24), nose (11), ear (6) and tracheal aspirate (7). B. catarrhalis appeared as Gram-negative cocci in white colonies which were oxidase- and catalase-positive and which did not produce acidification of sugars. The 3 related species, Neisseria caviae, N. ovis and N. cuniculi were also white but the 'true asaccharolytic Neisseria' studied presented a yellow pigment. Only a few strains of B. catarrhalis were able to grow on selective medium. However, when Catlin's chemically defined medium was used, all strains of B. catarrhalis had a unique requirement for arginine. This characteristic differentiated B. catarrhalis from N. caviae and N. ovis (non-requiring), N. cuniculi (required cystine, proline and arginine) and N. canis and N. elongata (both non-requiring). All strains of B. catarrhalis reduced nitrate and nitrite, possessed deoxyribonuclease activity and hydrolysed tributyrin to butyric acid. B. catarrhalis liberated high concentrations of butyric acid, N. caviae, N. ovis and N. cuniculi moderate concentrations and other species of Neisseria minimal concentrations. All strains of B. catarrhalis were resistant to acetazolamide and the absence of gamma-glutamyl transferase activity differentiated B. catarrhalis from atypical meningococci which were always positive.

Induction and properties of beta-adrenergic receptors during erythroid differentiation of Friend leukemic cells.

beta-Adrenergic receptors on Friend erythroleukemic cells were identified by the use of 125I-labeled hydroxybenzylpindolol, a potent beta-adrenergic antagonist. Binding of this ligand was saturable and stereospecific. The relative orders of potency of isoproterenol, epinephrine, and norepinephrine to displace bound hydroxybenzylpindolol indicate that the Friend cells have beta 2-adrenergic receptors. After culture for 6 days in the presence of dimethyl sulfoxide or hexamethylene bisacetamide, both undifferentiated and differentiated cells have a similar number of receptors (1500 per cell), but the density of beta receptors on the cell surface increases during the process of erythroid differentiation. Incubation of the Friend cells for 24 hr with high concentrations of butyric acid, dimethyl sulfoxide, or hexamethylenebisacetamide resulted in a striking increase of th number of beta-catecholamine receptors. The induction of beta-adrenergic receptors also occurred in the presence of the tumor promoter 12-O-tetradecanoylphorbol 13-acetate and dexamethasone.