Propionic Research Articles

Exercise Affects Mucosa-Associated Microbiota and Colonic Tumor Formation Induced by Azoxymethane in High-Fat-Diet-Induced Obese Mice

The only reliable factor that reduces the risk of colorectal carcinogenesis is physical activity. However, the underlying mechanisms remain unclear. In this study, we examined the effects of physical activity against gut microbiota, including mucosa-associated microbiota (MAM) on azoxymethane-induced colorectal tumors in obese mice. We divided the subjects into four groups: normal diet (ND), high-fat diet (HFD), ND + exercise (Ex), and HFD + Ex groups. The Ex group performed treadmill exercise for 20 weeks. Thereafter, fecal and colonic mucus samples were extracted for microbiota analysis. DNA was collected from feces and colonic mucosa, and V3–V4 amplicon sequencing analysis of the 16SrRNA gene was performed using MiSeq. The HFD group had significantly more colonic polyps than the ND group (ND 6.5 ± 1.3, HFD 11.4 ± 1.5, p < 0.001), and the addition of Ex suppressed the number of colonic polyps in ND and HFD groups (ND 6.5 ± 1.3, ND + Ex 2.8 ± 2.5, p < 0.05). The HFD group showed significantly lower concentrations of succinic, acetic, butyric, and propionic acids (mg/g) in feces, compared with the ND group (succinic acid HFD 0.59, ND 0.17; acetic acid HFD 0.63, ND 2.41; propionic acid HFD 0.10, ND 0.47; and N-butyric acid HFD 0.31, ND 0.93). In the case of ND, succinic acid and butyric acid tended to decrease with Ex (succinic acid ND 0.17, ND + Ex 0.12; N-butyric acid ND 0.93, ND + Ex 0.74 0.74). Succinic acid, acetic acid, butyric acid, and propionic acid levels in feces were significantly lower in the HFD group than in the ND group; in both feces and mucus samples, Butyricicoccus and Lactobacillus levels were significantly lower in the HFD group. Akkermansia was significantly increased in ND + Ex and HFD + Ex groups. Diet and exercise affected the number of colorectal tumors. Furthermore, diet and exercise alter intestinal MAM, which may be involved in colorectal tumor development.

Deflagration characteristics of N2 diluted propanal/air mixtures at elevated pressures

Hydrocarbon fuels, in addition to being direct sources of energy, also serve as crucial raw materials for numerous industrial processes. In this study, the oxidation of propanal to propionic acid under elevated pressures has garnered our attention due to the substantial heat release during the mixing of propanal and oxidants, posing considerable hazards to production. Fortunately, the introduction of N2 effectively mitigates these risks by reducing the laminar burning speed (SL) and peak deflagration pressure (Pm), and even preventing the ignition of mixtures. On this basis, the deflagration characteristics of propanal/N2/air mixtures were investigated in a 20 L spherical vessel at 348 K under various equivalent ratios (φ, 0.5 - 2.0), dilution rates (D, 0 - 0.5) and initial pressures (P0, 0.1 - 1.0 MPa). The combustion characteristics of propanal/N2/air were also analyzed through the 1-D laminar flame speed model, and the sensitivity analysis was performed to elucidate the effect of φ, D and P0 on the combustion of propanal. Results reveal that the addition of N2 stabilizes the flame propagation, and the Pm of propanal/N2/air mixtures decreases with the increasing D, with a sudden drop observed at a certain D level. However, the reduction of SL does not undergo an abrupt decrease across the entire dilution rate range. Furthermore, Pm exhibits a linear relationship with P0 at lower D, but this linear trend disappears once D approaches the critical suppression concentration. Interestingly, the critical suppression concentration of N2 increases with P0 at fuel-rich conditions, yet remains unaffected by P0 at fuel-lean conditions. Near the critical suppression concentration, a limiting burning speed (Slim) emerges, below which the flame is incapable of spontaneous propagation. Notably, Slim is not a fixed value, but varies according to the composition and initial state of the mixture. For a given gas component, an increase in P0 leads to a decline in Slim, while for gases with varying components, Slim is observed to be lower under fuel-rich conditions compared to fuel-lean scenarios. Also, both the addition of N2 and the augmentation of P0 significantly reduce the SL. When SL is comparable to the gas rise speed due to natural convection, the flame propagation becomes vulnerable to buoyancy instability. Meanwhile, the flame propagation may also be influenced by thermal diffusion instability and hydrodynamic instability. Under the combined effect of these instabilities, the flame is prone to be unstable. More importantly, when the flame contacting the upper wall of the is in a critical state where it can or cannot propagate downward, the irregularity of the disturbed flame may introduces uncertainty into the subsequent propagation, resulting in markedly different Pm even among mixtures with identical compositions.

Inactivation of Listeria monocytogenes on a laboratory medium and enoki mushrooms using organic acid and essential oil vapors

The aim of this study was to determine the antimicrobial activity of organic acid (OA) and essential oil (EO) vapors against Listeria monocytogenes on a laboratory medium and enoki mushrooms. Among 14 OA and 8 EO vapors tested, 3 OA vapors (acetic, formic, and propionic acid) and 3 EO vapors (cinnamon bark, citronella, and lemongrass) showed relatively strong antilisterial activity. On tryptic soy agar (TSA), all three OA vapors had a minimum inhibitory concentration (MIC) of 12.5 mg/L, while the minimum lethal concentration (MLC) of formic acid vapor was the lowest, at 50 mg/L, followed by acetic acid vapor (200 mg/L) and propionic acid vapor (400 mg/L). The MIC values of lemongrass, cinnamon bark, and citronella EO vapors were 25, 100, and 100 mg/L, respectively. The MLC of lemongrass EO vapor was 100 mg/L and MLCs of other EO vapors were >400 mg/L. Formic acid and lemongrass EO vapors showed a partial synergism on TSA (fractional inhibitory concentration index of 0.7500). For L. monocytogenes inoculated on enoki mushrooms, formic acid vapor at a concentration of ≥50 mg/L, as well as formic acid and lemongrass vapors in combination (1:2 vol ratio) at ≥ 75 mg/L, inactivated L. monocytogenes. These results indicate that formic acid vapor is effective at controlling the growth of L. monocytogenes on enoki mushrooms.

Machine-Learning-Based Kinetic-Free Hybrid Gray-Box Model to Predict Sulfuric-Acid-Catalyzed Esterification Reaction.

The sulfuric-acid-catalyzed esterification reaction of 2-butanol and propionic anhydride is a vital industrial process. In this paper, several experiments are conducted via reaction calorimetry to validate that both sulfuric and propionic acids have discernible catalytic effects on the reaction. This finding complicates the accurate description of the reaction kinetics through traditional methods. So this paper turns to a kinetic-free black-box model, Gaussian process regression (GPR) model via 24 experiments, as a more adaptable approach. Besides, the best GPR model is combined with traditional heat balance model to generate a hybrid gray-box model, which can give complete knowledge of reaction process. The hybrid gray-box model finally achieves maximum root-mean-square error (RMSE) of 0.0069 for conversion, 0.6535 for temperature, and 10.6087 for heat flow rate, underscoring its pretty good predictive ability.

Screening of Small-Molecule Libraries Using SARS-CoV-2-Derived Sequences Identifies Novel Furin Inhibitors

SARS-CoV-2 is the pathogen responsible for the most recent global pandemic, which has claimed hundreds of thousands of victims worldwide. Despite remarkable efforts to develop an effective vaccine, concerns have been raised about the actual protection against novel variants. Thus, researchers are eager to identify alternative strategies to fight against this pathogen. Like other opportunistic entities, a key step in the SARS-CoV-2 lifecycle is the maturation of the envelope glycoprotein at the RARR685↓ motif by the cellular enzyme Furin. Inhibition of this cleavage greatly affects viral propagation, thus representing an ideal drug target to contain infection. Importantly, no Furin-escape variants have ever been detected, suggesting that the pathogen cannot replace this protease by any means. Here, we designed a novel fluorogenic SARS-CoV-2-derived substrate to screen commercially available and custom-made libraries of small molecules for the identification of new Furin inhibitors. We found that a peptide substrate mimicking the cleavage site of the envelope glycoprotein of the Omicron variant (QTQTKSHRRAR-AMC) is a superior tool for screening Furin activity when compared to the commercially available Pyr-RTKR-AMC substrate. Using this setting, we identified promising novel compounds able to modulate Furin activity in vitro and suitable for interfering with SARS-CoV-2 maturation. In particular, we showed that 3-((5-((5-bromothiophen-2-yl)methylene)-4-oxo-4,5 dihydrothiazol-2-yl)(3-chloro-4-methylphenyl)amino)propanoic acid (P3, IC50 = 35 μM) may represent an attractive chemical scaffold for the development of more effective antiviral drugs via a mechanism of action that possibly implies the targeting of Furin secondary sites (exosites) rather than its canonical catalytic pocket. Overall, a SARS-CoV-2-derived peptide was investigated as a new substrate for in vitro high-throughput screening (HTS) of Furin inhibitors and allowed the identification of compound P3 as a promising hit with an innovative chemical scaffold. Given the key role of Furin in infection and the lack of any Food and Drug Administration (FDA)-approved Furin inhibitor, P3 represents an interesting antiviral candidate.

Dynamics of microbial ecology and their bio-preservative compounds formed during the panettones elaboration using sourdough-isolated strains as starter cultures

The present study evaluated the application of Limosilactobacillus fermentum IAL 4541 and Wickerhamomyces anomalus IAL 4533 isolated from sourdoughs and their combinations, for bio-conservative action in panettones, as well as to identify the antifungal volatile compounds. Samples from different fermentation steps were submitted to physicochemical and microbiological evaluation, as to know: sourdough after 48 h (A), 96 h (B), and 144 h (C); dough of the first fermentation (D); final dough after second fermentation (E), and baked panettone (F). In all treatments, lactic bacteria and yeast counts demonstrated a mechanism of proto-cooperation. Panettones containing L. fermentum or W. anomalus in their composition had longer shelf life, which indicates their effect as potential biopreservatives. The genetic sequencing data demonstrated the dominance of the Lactobacilli throughout the process, corroborating the data obtained by cultivable methods. A total of 59 volatile organic compounds were found in this study, and a hierarchical cluster analysis presented the separation between the production stages (C, E) and the most recurrent compounds in the final product (F). Of these compounds, the following stood out (n = 26): acids (7.7%), alcohols (23.1%), aldehydes and ketones (34.6%), and esters (34.6%). The treatments containing L. fermentum presented more diversity of volatile organic compounds with potential antifungal effect. There was a higher production of acetic (1.17–8.85 mmol/kg), phenyllactic (5–10.4 mmol/kg), and propionic (3.5–4.3 mmol/kg) acids in the final product. This study demonstrates the feasibility of applying endogenous starter cultures from sourdoughs, with great biopreservative activity, enabling the production of healthier and more natural panettones.

Fiber from elicited butternut pumpkin (Cucurbita moschata D. cv. Ariel) modulates the human intestinal microbiota dysbiosis

Elicited pumpkin was evaluated as a potential daily consumption product able to modulate the gut microbiota. An in vitro dynamic colonic fermentation performance with microbiota from obese volunteers was used. Prebiotic effects were observed after the pumpkin treatment. Bifidobacterium abundance was maintained during the treatment period whereas Lactobacillus increased in the transversal and descending colon. Conversely, Enterobacteriaceae and Clostridium groups were more stable, although scarce decreasing trends were observed for same species. Increments of Lactobacillus acidophilus and Limosilactobacillus fermentum (old Lactobacillus fermentum) were observed in the whole colonic tract after the treatment period. However, modulatory effects were mainly observed in the transversal and descending colon. Diverse bacteria species were increased, such as Akkermansia muciniphila, Bacteroides dorei, Cloacibacillus porcorum, Clostridium lactatifermentans, Ruminococcus albus, Ruminococcus lactaris, Coprococcus catus, Alistipes shahii or Bacteroides vulgatus. The prebiotic effect of the elicited pumpkin was provided by the fiber of the pumpkin, suggesting a release of pectin molecules in the transversal and distal colonic tract through low cellulosic fiber degradation, explaining the increases in the total propionic and butyric acid in these colonic sections. Also, a possible modulatory role of carotenoids from the sample was suggested since carotenes were found in the descending colon. Hence, the results of this research highlighted pumpkin as a natural product able to modulate the microbiota towards a healthier profile.

Assessment of the content of short-chain fatty acids in ulcerative colitis as an indicator of the patient's metabolic health

Numerous studies show that in the pathogenesis of ulcerative colitis (UC), a significant role is played by a change in the diversity of the intestinal microflora, which is associated with fewer bacteria producing short-chain fatty acids (SCFAs). SCFCS affect the differentiation and activation of cells of the immune system, play a protective role in maintaining the integrity of the epithelial barrier, participate in the regulation of intestinal peristalsis and blood supply to its wall, muscle anabolism, bioavailability of amino acids.The aim of the study. To evaluate the content of SCLC in the feces of UC patients with varying degrees of severity of the current attack, as well as to investigate the relationship between the content of SCLC with dietary characteristics, body mass index (BMI), and dyspenia.Materials and methods. The study involved 80 UC patients, conducted a survey, objective examination, filling out medical history and outpatient records, blood and stool sampling. The content of SCLC was determined in feces. The study of nutritional characteristics in patients with UC was conducted using a standardized questionnaire of the WHO CINDI program. Statistical methods: median (Me), upper and lower quartiles (P25, P75) were calculated; Mann-Whitney criterion; Kolmogorov-Smirnov criterion; nonparametric correlation analysis was performed.Results. The absolute content of SCFCS in the feces of patients with UC is lower than the reference values. The relative content of propionic acid in the subgroup with severe attack was significantly lower than in the remission subgroup, in the subgroup with mild and moderate attack of the disease. In patients with body weight deficiency, the relative content of propionic acid is lower than in UC patients with normal or overweight. A positive relationship was found between the total content of SCFCS in feces and the amount of dietary fiber consumed in the form of fruits and vegetables. In patients with dinapenia, the relative content of butyric acid in feces is significantly lower than in patients without dinapenia.

Ligand mediated self-assembly of cobalt nanoclusters for tunable supercapacitors

Self-assembly of thiolated cobalt-based nanoclusters was achieved by a simple and one-step synthesis process towards the development of a tunable hybrid supercapacitor. Here, we report the wet chemical synthesis of self-assembly of cobalt nanoclusters (CoNCs) using three different thiols namely glutathione (GS), 3-mercapto propyl sulfonate (MPS) and 3-mercapto propionic acid (MPA) protected individually. The variation in the capping ability of the thiolate ligands brings the proximal changes in the optical, structural and electrochemical properties. In CoNCs, the structural and morphological changes that evolved from the obtained GS-CoNCs, MPS-CoNCs, and MPA-CoNCs were confirmed using UV–vis spectroscopy, XRD, and TEM analysis. The stability of CoNCs and binding states of cobalt metal were determined using TG and XPS analysis respectively. The divergence in the rigidifying nature of various thiolated cobalt nanoclusters significantly influences their capacitance ability for energy storage via altering the porosity and electron transfer characteristics. The rigid dense multifunctional ligands like GS facilitate the electron-hole hopping process in the nano-pockets available in GS, which enhances the energy storage capability and diffusion among ligand-metal-ligand chains. Wherein, the other two ligands MPS and MPA show comparatively lower supercapacitance activities due to diverse functionality and rigidify. The charge-discharge studies explore the supercapacitor behaviour of GS, MPS and MPA-protected CoNCs with the specific capacitance of 540, 494 and 358 F g−1 respectively at the current density of 1 A g−1.

Enhancing the expression of the unspecific peroxygenase in Komagataella phaffii through a combination strategy

The unspecific peroxygenase (UPO) from Cyclocybe aegerita (AaeUPO) can selectively oxidize C–H bonds using hydrogen peroxide as an oxygen donor without cofactors, which has drawn significant industrial attention. Many studies have made efforts to enhance the overall activity of AaeUPO expressed in Komagataella phaffii by employing strategies such as enzyme-directed evolution, utilizing appropriate promoters, and screening secretion peptides. Building upon these previous studies, the objective of this study was to further enhance the expression of a mutant of AaeUPO with improved activity (PaDa-I) by increasing the gene copy number, co-expressing chaperones, and optimizing culture conditions. Our results demonstrated that a strain carrying approximately three copies of expression cassettes and co-expressing the protein disulfide isomerase showed an approximately 10.7-fold increase in volumetric enzyme activity, using the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. After optimizing the culture conditions, the volumetric enzyme activity of this strain further increased by approximately 48.7%, reaching 117.3 U/mL. Additionally, the purified catalytic domain of PaDa-I displayed regioselective hydroxylation of R-2-phenoxypropionic acid. The results of this study may facilitate the industrial application of UPOs.Key points• The secretion of the catalytic domain of PaDa-I can be significantly enhanced through increasing gene copy numbers and co-expressing of protein disulfide isomerase.• After optimizing the culture conditions, the volumetric enzyme activity can reach 117.3 U/mL, using the 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate.• The R-2-phenoxypropionic acid can undergo the specific hydroxylation reaction catalyzed by catalytic domain of PaDa-I, resulting in the formation of R-2-(4-hydroxyphenoxy)propionic acid.

The growth and nutrient removal properties of heterotrophic microalgae Chlorella sorokiniana in simulated wastewater containing volatile fatty acids

To reduce the high cost of organic carbon sources in waste resource utilization in the cultivation of microalgae, volatile fatty acids (VFAs) derived from activated sludge were used as the sole carbon source to culture Chlorella sorokiniana under the heterotrophic cultivation. The addition of VFAs in the heterotrophic condition enhanced the total nitrogen (TN) and phosphorus (TP) removal of C. sorokiniana, which proved the advantageous microalgae in using VFAs in the heterotrophic culture after screening in the previous study. To discover the possible mechanism of nitrogen and phosphorus adsorption in heterotrophic conditions by microalgae, the effect of different ratios of VFAs (acetic acid (AA): propionic acid (PA): butyric acid (BA)) on the nutrient removal and growth properties of C. sorokiniana was studied. In the 8:1:1 group, the highest efficiency (77.19%) of VFAs assimilation, the highest biomass (0.80 g L−1) and lipid content (31.35%) were achieved, with the highest TN and TP removal efficiencies of 97.44 % and 91.02 %, respectively. Moreover, an aerobic denitrifying bacterium, Pseudomonas, was determined to be the dominant genus under this heterotrophic condition. This suggested that besides nitrate uptake and utilization by C. sorokiniana under the heterotrophy, the conduct of the denitrification process was also the main reason for obtaining high nitrogen removal efficiency.

PSI-12 Dietary isoacids modulate nutrient digestibility and fermentation products in ileal digesta and feces of growing pigs fed corn-soybean meal diets

Abstract Branched-chain fatty acids, or isoacids, are the product of branched-chain amino acid fermentation and have been associated with benefits on the productivity of ruminants, primarily by positively modulating gut microbes and promoting gastrointestinal health. The objective of this study was to determine the optimal inclusion level of isoacid blend product based on apparent ileal digestibility (AID), apparent total tract digestibility (ATTD) of nutrients, and fermentation products in growing pigs fed corn-soybean meal diets. Twelve cannulated pigs [body weight (BW) = 20.9 + 0.6 kg] were used in a 5-period switch-back design with 6 diets and 2 replicate pigs in each period (n = 10 observations per dietary treatment). Experimental diets consisted of increasing levels (0%, 0.5%, 0.75%, 1%, 1.25%, and 1.5%) of an isoacid blend (isobutyrate, isovalerate, and 2-methyl butyrate, 1:1:1) added to a corn-soybean meal basal diet containing titanium dioxide as an indigestible marker. Each experimental period lasted 14 d: 10 d for acclimatization to the diets, 2 d for fecal collection, and 2 d for digesta collection. Diets, fecal, and ileal digesta samples were analyzed for gross energy (GE), crude protein (CP), fiber composition, amino acids (AA), and titanium. The concentration of short-chain fatty acids and ammonia were analyzed in digesta and fecal samples. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of increasing levels of isoacids. Dietary supplementation of isoacids improved (P < 0.1, linear and/or quadratic) AID of crude fiber and hemicellulose and most of the indispensable AA (except Met+Cys, Trp, and Val) as well as ATTD of CP, GE, neutral detergent fiber, and hemicellulose. In addition, ATTD of Arg, His, Ile, Leu, Met+Cys, Phe, Thr, Trp, and Val increased quadratically (P < 0.1). Collectively, 1% isoacid inclusion promoted the greatest responses in most measured variables (% increase: unsupplemented vs. 1%): AID of Lys (9.3%), Met (5.7%), Thr (17.8%), Leu (7.4%), Ile (9.2%), Phe (7.8%), His (5.9%), Arg (4.9%); ATTD of CP (2.1%), GE (1.3%), NDF (3.9%), hemicellulose (>50%), overall indispensable AA (9.5%), overall dispensable AA (8.6%). On the other hand, the inclusion of isoacids quadratically increased (P = 0.071) the concentration of ammonia and decreased (P < 0.1) the concentration of acetic acid, iso-valeric acid, and total VFA in ileal digesta samples. In fecal samples, the proportion of acetic acid decreased (P < 0.05) quadratically while the proportion of propionic, valeric, and caproic acids increased (P < 0.1). In conclusion, dietary supplementation of isoacids at 1% can improve dietary nutrient digestibility, particularly ileal AA digestibility. Based on the changes in fermentation products, the modulation of intestinal microbiota through the gastrointestinal tract could be potentially related to the effects of isoacids on nutrient digestibility. However, the effects of isoacids supplementation on intestinal microbiota must be determined.

Effects of the fermentation quality and microbial community of waxy maize mixed with fodder soybean silage

Waxy maize (Zea mays L. sinensis Kulesh) is highly regarded for its high nutritional content and unique taste. Although the stalks and leaves contain high carbohydrate levels after ear harvesting, inadequate crude protein (CP) limits the utilization and promotion of waxy maize silage in animal husbandry. In this study, waxy maize and fodder soybeans were mixed for sowing in different proportions [1:0 (CK), 1:1 (A1), 1:2 (A2), 1:3 (A3), and 1:4 (A4)] to investigate the effects of different mixing ratios on the growth of the waxy maize, the chemical indices, fermentation quality, and the microbial community of the mixed silage after ear harvesting. The mixed planting of waxy maize and fodder soybeans in different proportions had no effect on the yield and quality of the waxy maize ears and increased the aboveground biomass after ear harvesting. After ear harvesting, the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents significantly decreased, and the CP content and relative feeding value (RFV) gradually increased in the mixed silage. The pH of the treatments was lower than 4.2 except for A4, and the lowest ammonia nitrogen (AN) concentration was observed in A3. With increasing proportions of fodder soybeans, the abundance of beneficial bacteria increased and that of harmful bacteria decreased; Firmicutes and Lactobacillus were the dominant phylum and genus, respectively, and both increased gradually. Redundancy analysis (RDA) revealed that the fermentation indices affecting the microbial community composition in the silage were inconsistent among the different mixed sowing combinations. The Mantel test showed that the composition of the microbial communities in the treatments was significantly correlated with the ADF, water-soluble carbohydrate (WSC), and propionic acid (PA) contents. Comprehensive analysis revealed that the optimal mixed sowing ratio of waxy maize to fodder soybeans was 1:3, and waxy maize and fodder soybeans silage can increase the utilization of aboveground biomass and improve the fermentation quality and feeding quality of silage by changing the microbial community. These findings lay a certain theoretical foundation for improving the utilization of waxy maize.

Inulin Reduces Kidney Damage in Type 2 Diabetic Mice by Decreasing Inflammation and Serum Metabolomics.

This study is aimed at assessing the impact of soluble dietary fiber inulin on the treatment of diabetes-related chronic inflammation and kidney injury in mice with type 2 diabetes (T2DM). The T2DM model was created by feeding the Institute of Cancer Research (ICR) mice a high-fat diet and intraperitoneally injecting them with streptozotocin (50 mg/kg for 5 consecutive days). The thirty-six ICR mice were divided into three dietary groups: the normal control (NC) group, the T2DM (DM) group, and the DM + inulin diet (INU) group. The INU group mice were given inulin at the dose of 500 mg/kg gavage daily until the end of the 12th week. After 12 weeks, the administration of inulin resulted in decreased serum levels of fasting blood glucose (FBG), low-density lipoprotein cholesterol (LDL-C), blood urea nitrogen (BUN), and creatinine (CRE). The administration of inulin not only ameliorated renal injury but also resulted in a reduction in the mRNA expressions of inflammatory factors in the spleen and serum oxidative stress levels, when compared to the DM group. Additionally, inulin treatment in mice with a T2DM model led to a significant increase in the concentrations of three primary short-chain fatty acids (SCFAs) (acetic acid, propionic acid, and butyric acid), while the concentration of advanced glycation end products (AGEs), a prominent inflammatory factor in diabetes, exhibited a significant decrease. The results of untargeted metabolomics indicate that inulin has the potential to alleviate inflammatory response and kidney damage in diabetic mice. This beneficial effect is attributed to its impact on various metabolic pathways, including glycerophospholipid metabolism, taurine and hypotaurine metabolism, arginine biosynthesis, and tryptophan metabolism. Consequently, oral inulin emerges as a promising treatment option for diabetes and kidney injury.

Adaptable heat pump-assisted dividing-wall column design for intensified downstream processing of bio-propionic acid

Propionic acid is a valuable platform chemical that is usually produced via fossil routes. As these are energy-intensive and eco-unfriendly processes, fermentative production of propionic acid is becoming more attractive. However, the complex downstream processing (due to low achievable product concentrations, high water content, presence of by-products and thermodynamic constraints), presents a potential barrier to scale-up this technology. This original research proposes a novel intensified large-scale (production capacity of ∼ 20 ktonne/y) process for the final recovery of propionic acid after the initial biomass and counterion removal. The vacuum distillation steps ensure recovery of high-purity succinic acid product (>99.9 wt%) and a water stream that may be recycled to the fermentation to reduce the fresh water requirements. The main unit that follows is a highly integrated heat pump-assisted dividing-wall column (DWC), which allows the effective separation of propionic (>99.9 wt%) and acetic acid (99.4 wt%) products. Alternatively, it can serve as a reactive DWC that performs the esterification and separation of methyl propionate (99.8 wt%), methyl acetate (91.0 wt%) as higher added value products, and water by-product. If needed, extractive distillation can be implemented additionally to recover methyl acetate at higher purity (99.9 wt%). Overall, both options are proven to be economically interesting (recovery costs of 0.399 – 0.469 $/kg considering the product price of 1.349 – 1.802 $/kg) and environmentally attractive (3.206 – 3.678 kWthh/kg).

Fire-Safe thermoplastic polyurethane created by a novel Silane-Containing phosphate

Phosphate is a kind of effective flame retardant for thermoplastic polyurethane (TPU), but it always results in great damage to mechanical properties. Herein, an organic silane-containing phosphonate (CTA-APTES) was prepared by 3-[Hydroxy (phenyl) phosphoryl]propanoic acid, tyramine and γ-aminopropyl triethoxysilane to simultaneously improve the fire safety and decreasing the mechanical loss of TPU. At the loading of 5.0 wt%, TPU/CTA-APTES5 passed the UL-94 V-0 rating, and its limiting oxygen index was 28.5 %, reaching the non-inflammable grade. While showing remarkable flame-retardant effect on TPU, just as important, the tensile strength and elongation at break of TPU/CTA-APTES5 were 11.34 MPa and 244.5 % respectively, increased by 85 % and 1471 % compared with those of control sample TPU/CEPPA-TA5, remarkably reducing the damage of phosphate to mechanical properties of the substrate. This work provided an efficient strategy to utilize silane-containing phosphate to fabricate high-performance fire-safe TPU.

Quantifying fecal and plasma short-chain fatty acids in healthy Thai individuals

Short-chain fatty acids (SCFAs) are involved in important physiological processes such as gut health and immune response, and changes in SCFA levels can be indicative of disease. Despite the importance of SCFAs in human health and disease, reference values for fecal and plasma SCFA concentrations in healthy individuals are scarce. To address this gap in current knowledge, we developed a simple and reliable derivatization-free GC-TOFMS method for quantifying fecal and plasma SCFAs in healthy individuals. We targeted six linear- and seven branched-SCFAs, obtaining method recoveries of 73-88% and 83-134% in fecal and plasma matrices, respectively. The developed methods are simpler, faster, and more sensitive than previously published methods and are well suited for large-scale studies. Analysis of samples from 157 medically confirmed healthy individuals showed that the total SCFAs in the feces and plasma were 34.1 ± 15.3 µmol/g and 60.0 ± 45.9µM, respectively. In fecal samples, acetic acid (Ace), propionic acid (Pro), and butanoic acid (But) were all significant, collectively accounting for 89% of the total SCFAs, whereas the only major SCFA in plasma samples was Ace, constituting of 93% of the total plasma SCFAs. There were no statistically significant differences in the total fecal and plasma SCFA concentrations between sexes or among age groups. The data revealed, however, a positive correlation for several nutrients, such as carbohydrate, fat, iron from vegetables, and water, to most of the targeted SCFAs. This is the first large-scale study to report SCFA reference intervals in the plasma and feces of healthy individuals, and thereby delivers valuable data for microbiome, metabolomics, and biomarker research.

Structural characterization and prebiotic activity of rhamnogalacturonan-I rich pumpkin pectic polysaccharide extracted by alkaline solution

The present study aimed to investigate the structural and physicochemical characteristics of alkali-extracted pectic polysaccharide (AkPP) and to evaluate its prebiotic effects. AkPP was obtained from pumpkin pulp using an alkaline extraction method. AkPP, which had a molecular weight (Mw) of mainly 13.67 kDa and an esterification degree of 9.60 %, was composed mainly of galacturonic acid (GalA), rhamnose (Rha), galactose, and arabinose. The ratio of the homogalacturonan (HG) region to the rhamnogalacturonan-I (RG-I) region in AkPP was 48.74:43.62. In the nuclear magnetic resonance spectrum, the signals indicating α-1,4-linked D-GalA, α-1,2-linked L-Rha, α-1,2,4-linked L-Rha residues were well resolved, demonstrating the presence of the HG and RG-I regions in its molecular structure. Collectively, AkPP was low methoxyl pectin rich in the RG-I region with short side chains and had a low Mw. Thermal analysis revealed that AkPP had good thermal stability. Compared to inulin, AkPP more effectively promoted the proliferation of Lactobacillus acidophilus, Lacticaseibacillus rhamnosus GG, Lacticaseibacillus casei, and Lacticaseibacillus paracasei and the production of lactic, acetic, and propionic acids. This study presents the unique structural features of AkPP and provides a scientific basis for further investigation of the potential of AkPP as a promising prebiotic.

Petroleum ether extract of Schisandra sphenanthera prevents hyperglycemia and insulin resistance in association with modulation of sweet taste receptors and gut microbiota in T2DM rats

Ethnopharmacological relevanceSchisandra sphenanthera (Schisandra sphenanthera Rehd. et Wils.) is the dried mature fruit of Schisandra sphenanthera, a plant in the Magnoliaceae family. It was used in the treatment of diabetes mellitus in the Jade Fluid Decoction and the Xiaoke pills, which were recorded in ancient books. However, its mechanism of action in the treatment of type 2 diabetes mellitus (T2DM) was unclear and needs further study. Aim of the studyThis research aimed to investigate the chemical composition and lignan content of Schisandra sphenanthera petroleum ether parts (SPEP) and to evaluate the effects of SPEP on sweet taste receptors (STRs) and intestinal flora in rats on a high-fat diet (HFD). Additionally, the relationships between SPEP and hyperglycemia and insulin resistance were examined. Materials and methodsGC-MS was used to determine the chemical composition of SPEP, and HPLC was used to determine the lignin content. A combination of the HFD and the administration of streptozotocin (STZ) was employed to generate a rat model of T2DM. Petroleum ether extracts from Schisandra sphenanthera were used as the focus of the research to evaluate the effects of these extracts on the glucolipid metabolism of T2DM rats, as well as the underlying mechanisms. ResultsAnalysis of the GC-MS spectrum of SESP revealed a total of 58 compounds. HPLC analysis revealed that SPEP had the highest concentration of Schisandrin A and the lowest concentration of Schisandrol A. The drug administration intervention resulted in a significant decrease in body weight and pancreatic weight of diabetic rats compared to the Normal group. When compared to the Model group, the body weight of rats in the drug administration group and the Metformin group had a more moderate decrease, while the pancreatic weight and pancreatic-to-body ratio increased. The Model group shown significant increases in FBG, OGTT, GHb, TC, TG, LDL-C, ALT, AST, MDA, FINS, and NEFA, as well as significant decreases in HDL-C and SOD, when compared to the Normal group (P<0.05). The administration of each group was found to be significantly effective in decreasing FBG, OGTT, GHb, TC, TG, LDL-C, ALT, AST, MDA, FINS, NEFA, while increasing HDL-C and SOD when compared to the Model group. The application of SPEP had a positive impact on hepatocyte swelling, hepatocyte degeneration, and necrosis, as well as the morphological structure of pancreatic islet cells. Furthermore, the protein expression levels of T1R2, TRPM5 and GLP-1 in the small intestine of the Model group were reduced. After a period of six weeks, the protein expression levels began to align more closely with those of the Normal group of rats. Analysis of 16S rRNA sequencing revealed that the intestinal microbiota of diabetic rats was significantly disrupted, with a decrease in the abundance of the Firmicutes phylum and an increase in the abundance of the Bacteroidetes phylum. Furthermore, the composition of the dominant genus was distinct from that of the control group. After the drug intervention, the microbiota of diabetic rats was significantly altered, exhibiting a higher abundance and diversity, as well as a significant enrichment of the community. The SPEP treatment resulted in a significant increase in acetic acid, propionic acid, and butyric acid. ConclusionsThe findings of this research indicated that SPEP could be effective in treating T2DM through the regulation of STRs, the adjustment of disturbed metabolite levels, and the alteration of intestinal flora.

The New Buffer Salt-Protected Sodium Butyrate Promotes Growth Performance by Improving Intestinal Histomorphology, Barrier Function, Antioxidative Capacity, and Microbiota Community of Broilers

In this study, a commercial sodium butyrate protected by a new buffer salt solution (NSB) was tested to determine whether it can be used as an antibiotic alternative in broiler production. A total of 192 1-day-old broilers were randomly allocated to three dietary treatments: soybean meal diet (CON), antibiotic diet (ANT, basal diet + 100 mg/kg aureomycin), and NSB (basal diet + 800 mg/kg NSB). The growth performance, serum anti-inflammatory cytokines, intestinal morphology, gut barrier function, antioxidative parameters, SCFAs’ content, and cecal microbiota were analyzed. The result showed that NSB significantly improved ADFI and ADG (p &lt; 0.01), and decreased FCR (p &lt; 0.01). Serum anti-inflammatory cytokine IL-10 was up-regulated (p &lt; 0.01), and pro-inflammatory TNF-α was down-regulated (p &lt; 0.05) by NSB supplementation. H&amp;E results showed that VH and the VH/CD ratio significantly increased (p &lt; 0.05) in the jejunum and ileum in the NSB group. Furthermore, ZO-1 (p &lt; 0.01), claudin-1 (p &lt; 0.01), and occludin (p &lt; 0.05) in the jejunum and claudin-1 (p &lt; 0.01) and mucin-2 (p &lt; 0.05) in the ileum were significantly up-regulated in the NSB group. Additionally, SOD (p &lt; 0.05) and the T-AOC/MDA ratio (p &lt; 0.01) in the jejunum and SOD in the ileum were significantly increased (p &lt; 0.05) in the NSB group. The MDA level also significantly increased (p &lt; 0.01) in the ANT group in the jejunum. Propionic acid (p &lt; 0.05) and butyric acid (p &lt; 0.01) content significantly increased in the NSB group in the jejunum and ileum segments. The 16S rRNA sequencing results showed no significant difference (p &gt; 0.05) in alpha and beta diversity among the groups. LEFSe analysis also indicated that Peptostreptococcaceae, Colidextribacter, Firmicutes, Oscillospira, and Erysipelatoclostridiaceae, which promote SCFA production (p &lt; 0.05), were identified as dominant taxon-enriched bacterial genera in the NSB group. The Spearman correlation analysis revealed that Colidextribacter with ADFI, ADG, VH, claudin-1 (p &lt; 0.05), and unclassified_f__Peptostreptococcaceae with ADFI, IL-10, and ZO-1 were positively correlated (p &lt; 0.05). Furthermore, ADFI and ADG with IL-10, claudin-1, SOD, T-AOC, and butyric acid (p &lt; 0.05), and similarly, ADG with VH (p &lt; 0.05), showed a positive correlation. In conclusion, NSB enhanced the growth performance by improving jejunum and ileum morphology, and serum anti-inflammatory cytokines, and by regulating the intestinal barrier function and antioxidant capacity, SCFAs’ content, and cecum microbiota, showing its potential use as an alternative to antibiotics in poultry nutrition.