Mucin alleviates colonic barrier dysfunction by promoting spermine accumulation through enhanced arginine metabolism in Limosilactobacillus mucosae.

Dietary fiber deprivation is linked to probiotic extinction, mucus barrier dysbiosis, and the overgrowth of mucin-degrading bacteria. However, whether and how mucin could rescue fiber deprivation-induced intestinal barrier defects remains largely unexplored. Here, we sought to investigate the potential role and mechanism by which exogenous mucin maintains the gut barrier function. The results showed that dietary mucin alleviated fiber deprivation-induced disruption of colonic barrier integrity and reduced spermine production in vivo. Importantly, we highlighted that microbial-derived spermine production, but not host-produced spermine, increased significantly after mucin supplementation, with a positive association with upgraded colonic Lactobacillus abundance. After employing an in vitro model, the microbial-derived spermine was consistently dominated by both mucin and Lactobacillus spp. Furthermore, Limosilactobacillus mucosae was identified as an essential spermine-producing Lactobacillus spp., and this isolated strain was responsible for spermine accumulation, especially after adhering to mucin in vitro. Specifically, the mucin-supplemented bacterial supernatant of Limosilactobacillus mucosae was verified to promote intestinal barrier functions through the increased spermine production with a dependence on enhanced arginine metabolism. Overall, these findings collectively provide evidence that mucin-modulated microbial arginine metabolism bridged the interplay between microbes and gut barrier function, illustrating possible implications for host gut health. IMPORTANCE: Microbial metabolites like short-chain fatty acids produced by dietary fiber fermentation have been demonstrated to have beneficial effects on intestinal health. However, it is essential to acknowledge that certain amino acids entering the colon can be metabolized by microorganisms to produce polyamines. The polyamines can promote the renewal of intestinal epithelial cell and maintain host-microbe homeostasis. Our study highlighted the specific enrichment by mucin on promoting the arginine metabolism in Limosilactobacillus mucosae to produce spermine, suggesting that microbial-derived polyamines support a significant enhancement on the goblet cell proliferation and barrier function.

A supramolecular hydrogel dressing with antibacterial, immunoregulation, and pro-regeneration ability for biofilm-associated wound healing.

Chronic wound treatment has emerged as a significant healthcare concern worldwide due to its substantial economic burden and the limited effectiveness of current treatments. Effective management of biofilm infections, regulation of excessive oxidative stress, and promotion of tissue regeneration are crucial for addressing chronic wounds. Hydrogel stands out as a promising candidate for chronic wound treatment. However, its clinical application is hindered by the difficulty in designing and fabricating easily and conveniently. To overcome these obstacles, we present a supermolecular G-quadruplex hydrogel with the desired multifunction via a dynamic covalent strategy and Hoogsteen-type hydrogen bonding. The G-quadruplex hydrogel is made from the self-assembly of guanosine, 2-formylphenyboronic acid, polyethylenimine, and potassium chloride, employing dynamic covalent strategy and Hoogsteen-type hydrogen bonding. In the acidic/oxidative microenvironment associated with bacterial infections, the hydrogel undergoes controlled degradation, releasing the polyethylenimine domain, which effectively eliminates bacteria. Furthermore, nanocomplexes comprising guanosine monophosphate and manganese sulfate are incorporated into the hydrogel skeleton, endowing it with the ability to scavenge reactive oxygen species and modulate macrophages. Additionally, the integration of basic fibroblast growth factor into the G-quadruplex skeleton through dynamic covalent bonds facilitates controlled tissue regeneration. In summary, the facile preparation process and the incorporation of multiple functionalities render the G-quadruplex hydrogel a highly promising candidate for advanced wound dressing. It holds great potential to transition from laboratory research to clinical practice, addressing the pressing needs of chronic wound management.

Ultrasmall polyvinylpyrrolidone-modified iridium nanoparticles with antioxidant and anti-inflammatory activity for acute pancreatitis alleviation.

Acute pancreatitis (AP) is a common and serious acute inflammatory disease with high severity rate and mortality. Inflammation and oxidative stress play an extremely important role in the development of AP disease. Polyvinylpyrrolidone-modified iridium nanoparticles (IrNP-PVP) have multienzyme mimetic activity, and the aim of this article is to discuss the therapeutic alleviative effects of the ultrasmall nanozymes IrNP-PVP on AP through their antioxidant and anti-inflammatory effects. IrNP-PVP were proved to inhibit inflammation and scavenge reactive oxygen species (ROS) at the cellular level. The synthetic IrNP-PVP exhibit remarkable antioxidant and anti-inflammatory activities in the prevention and treatment of AP mice by establishing murine AP model, which can reduce the oxidative stress and inflammatory response. The results of this article indicated that the ultrasmall nanozymes IrNP-PVP effectively alleviate AP via scavenging ROS as well as suppressing inflammation both in vivo and in vitro, which might provide enormous promise for the AP management.

Pancreatic cancer pathology image segmentation with channel and spatial long-range dependencies.

Based on deep learning, pancreatic cancer pathology image segmentation technology effectively assists pathologists in achieving improved treatment outcomes. However, compared to traditional image segmentation tasks, the large size of tissues in pathology images requires a larger receptive field. While methods based on dilated convolutions or attention mechanisms can enhance the receptive field, they cannot capture long-range feature dependencies. Directly applying self-attention mechanisms to capture long-range dependencies results in intolerable computational complexity. To address these challenges, we introduce a channel and spatial self-attention (CS) Module designed for efficiently capturing both channel and spatial long-range feature dependencies in pancreatic cancer pathological images. Specifically, the channel and spatial self-attention module consists of an adaptive channel self-attention module and a window-shift spatial self-attention module. The adaptive channel self-attention module adaptively pools features to a fixed size to capture long-range feature dependencies. While the window-shift spatial self-attention module captures spatial long-range dependencies in a window-based manner. Additionally, we propose a re-weighted cross-entropy loss to mitigate the impact of long-tail distribution on performance. Our proposed method surpasses state-of-the-art on both our Pancreatic Cancer Pathology Image (PCPI) dataset and the GlaS challenge dataset. The mDice and mIoU have achieved 73.93% and 59.42% in our PCPI dataset.

L-Arabinose inhibits Shiga toxin type 2-converting bacteriophage induction in Escherichia coli O157:H7.

The pathogenicity of Escherichia coli (E. coli) O157:H7 is predominantly associated with Shiga toxin 2 (Stx2) that poses a huge threat to human and animal intestinal health. Production of Stx2 requires expression of stx2 gene, which is located in the genome of lambdoid Stx2 prophage. Growing evidence has implicated that many commonly consumed foods participate in the regulation of prophage induction. In this study, we aimed to explore whether specific dietary functional sugars could inhibit Stx2 prophage induction in E. coli O157:H7, thereby preventing Stx2 production and promoting intestinal health. We demonstrated that Stx2 prophage induction in E. coli O157:H7 was strongly inhibited by L-arabinose both in vitro and in a mouse model. Mechanistically, L-arabinose at doses of 9, 12, or 15 mM diminished RecA protein levels, a master mediator of the SOS response, contributing to reduced Stx2-converting phage induction. L-Arabinose inhibited quorum sensing and oxidative stress response, which are known as positive regulators of the SOS response and subsequent Stx2 phage production. Furthermore, L-arabinose impaired E. coli O157:H7 arginine transport and metabolism that were involved in producing Stx2 phage. Collectively, our results suggest that L-arabinose may be exploited as a novel Stx2 prophage induction inhibitor against E. coli O157:H7 infection.

Ectopic intrapulmonary thyroid masquerading as metastatic carcinoma of the lung: a rare case scenario.

BACKGROUND: The intrapulmonary ectopic thyroid gland is exceedingly rare since the ectopic thyroid was discovered. Only eight cases have been reported in the worldwide literature. We present a case of multiple intrapulmonary ectopic thyroid glands with nodular goiter in a 10-year-old girl. CASE PRESENTATION: The girl was found with multiple intrapulmonary nodules in bilateral lungs during the treatment of nodular goiter. The intrapulmonary lesions were initially thought to be a high possibility of metastatic cancer. A computed tomography-guided percutaneous lung biopsy was performed, and the pathological examination confirmed that the diagnosis was ectopic intrapulmonary thyroid. CONCLUSION: The ectopic intrapulmonary thyroid should be considered when children with nodular goiter presenting with suspected metastases in the lung.

Molecular dynamics simulation of adsorption and separation of xylene isomers by Cu-HKUST-1.

Metal-organic frameworks (MOFs) are widely used in the adsorption separation of various gases. A fundamental understanding of the effective separation of xylene isomers helps improve aromatic products' separation efficiency and reduce industrial separation costs. Grand Canonical Monte Carlo (GCMC) simulations combined with Molecular Science is widely used to predict gas adsorption and diffusion in single crystals with metal-organic frameworks. We performed a GCMC + MD combined approach to study xylene isomers' adsorption and separation in Cu-HKUST-1 to predict the permeability and selectivity of the ternary gas mixture in the MOF with the adsorption and diffusion usage data. Most current studies take into account the computational cost and difficulty. Most recent research models are limited to the adsorption of a single or specific molecule, such as hydrogen, methane, carbon dioxide, etc. For this reason, we report an attempt to study the adsorption separation of aromatic gases (p-xylene/o-xylene/m-xylene) based on Cu-HKUST-1 single-crystal materials based on some previous research methods with an appropriate increase in computational cost. To predict the adsorption selectivity and permeability of the ternary mixture of xylene isomers on the MOF surface, the model simulation calculates key parameters of gas adsorption, including gas adsorption volume (N), the heat of adsorption (Q st), Henry coefficient (K), and diffusion coefficient (D).

Transcriptome Analysis Reveals Putative Induction of Floral Initiation by Old Leaves in Tea-Oil Tree (Camellia oleifera 'changlin53').

Floral initiation is a major phase change in the spermatophyte, where developmental programs switch from vegetative growth to reproductive growth. It is a key phase of flowering in tea-oil trees that can affect flowering time and yield, but very little is known about the molecular mechanism of floral initiation in tea-oil trees. A 12-year-old Camellia oleifera (cultivar 'changlin53') was the source of experimental materials in the current study. Scanning electron microscopy was used to identify the key stage of floral initiation, and transcriptome analysis was used to reveal the transcriptional regulatory network in old leaves involved in floral initiation. We mined 5 DEGs related to energy and 55 DEGs related to plant hormone signal transduction, and we found floral initiation induction required a high level of energy metabolism, and the phytohormones signals in the old leaves regulate floral initiation, which occurred at stage I and II. Twenty-seven rhythm-related DEGs and 107 genes associated with flowering were also identified, and the circadian rhythm interacted with photoperiod pathways to induce floral initiation. Unigene0017292 (PSEUDO-RESPONSE REGULATOR), Unigene0046809 (LATE ELONGATED HYPOCOTYL), Unigene0009932 (GIGANTEA), Unigene0001842 (CONSTANS), and Unigene0084708 (FLOWER LOCUS T) were the key genes in the circadian rhythm-photoperiod regulatory network. In conjunction with morphological observations and transcriptomic analysis, we concluded that the induction of floral initiation by old leaves in C. oleifera 'changlin53' mainly occurred during stages I and II, floral initiation was completed during stage III, and rhythm-photoperiod interactions may be the source of the main signals in floral initiation induced by old leaves.

Dietary Supplementation of 25-Hydroxyvitamin D3 Improves Growth Performance, Antioxidant Capacity and Immune Function in Weaned Piglets.

This study was conducted to evaluate the effects of 25-hydroxyvitamin D3 (25(OH)VD3) and Vitamin D3 (VD3) supplemented in the diet of weaned piglets on their growth performance, bone quality, intestinal integrity, immune function and antioxidant capacity. A total of 192 weaned piglets were allocated into four groups and they were fed a control diet containing 2000 IU VD3 (negative control, NC), NC + 100 ppm colistin sulfate (positive control, PC), NC + 2000 IU VD3 (VD3) and NC + 2000 IU 25(OH)VD3 (25(OH)VD3). The results showed that 25(OH)VD3 improved the growth performance, bone quality and antioxidase activity of piglets compared with the other groups. Meanwhile, 25(OH)VD3 up-regulated ileal mRNA expressions of tight junction proteins and host defense peptides. The VD3 group had an increased intestinal sIgA content and mRNA expression of pBD-1 compared with the NC group. Both groups of VD3 and 25(OH)VD3 altered the microbial ß-diversity compared with the NC group, and 25(OH)VD3 increased ileal concentrations of acetate and butyrate. In conclusion, our findings indicated that a regular dosage of 2000 IU VD3 in the weaned piglets' diet did not achieve optimal antioxidant capacity and immune function. 25(OH)VD3 had better growth performance than VD3 at the same inclusion level, which is associated with the improved intestinal integrity and antioxidant capacity.

Cytochrome P450 family 17 subfamily A member 1 mutation causes severe pseudohermaphroditism: A case report.

BACKGROUND: 17α-Hydroxylase deficiency (17-OHD) is a rare form of congenital adrenal hyperplasia, characterized by hypertension, hypokalemia, and gonadal dysplasia. However, due to the lack of a comprehensive understanding of this disease, it is prone to misdiagnosis and missed diagnosis, and there is no complete cure. CASE SUMMARY: We report a female patient with 17-OHD. The patient was admitted to the Department of Neurology of our hospital due to limb weakness. During treatment, it was found that the patient's condition was difficult to correct except for hypokalemia, and her blood pressure was difficult to control with various antihypertensive drugs. She was then transferred to our department for further treatment. On physical examination, the patient's gonadal development was found to be abnormal, and chromosome analysis demonstrated karyotype 46,XY. Considering the possibility of 17-OHD, the cytochrome P450 family 17 subfamily A member 1 (CYP17A1) test was performed to confirm the diagnosis. CONCLUSION: The clinical manifestations of 17-OHD are complex. Hormone determination, imaging examination, chromosome determination and CYP17A1 gene test are helpful for early diagnosis.

An overview of walnuts application as a plant-based.

The plant-based refers to plant-based raw materials or products that are available as the source of protein and fat. Utilization and development of walnuts as a plant-based, resulting in a high-quality protein-rich walnut plant-based product: walnut protein powder and walnut peptides. Progress in research on the application of walnuts as a plant-based has been advanced, solving the problem of wasted resources and environmental pollution caused by the fact that walnut residue, a product of walnuts after oil extraction, is often thrown away as waste, or becomes animal feed or compost. This paper reviews and summarizes the research and reports on walnut plant-based at home and abroad, focusing on the application of walnut plant-based in the preparation process (enzymatic and fermentation methods) and the biological activity of the walnut protein and walnut peptide, to provide a theoretical basis for the further processing of walnuts as a walnut plant-based. It can make full use of walnut resources and play its nutritional and health care value, develop and build a series of walnut plant-based products, improve the competitiveness of walnut peptide products, turn them into treasure, and provide more powerful guidance for the development of food and medicine health industry in Yunnan.

The High Level of Xylooligosaccharides Improves Growth Performance in Weaned Piglets by Increasing Antioxidant Activity, Enhancing Immune Function, and Modulating Gut Microbiota.

The aim of this study was to investigate the effects of the high level of xylooligosaccharides (XOS) on growth performance, antioxidant capability, immune function, and fecal microbiota in weaning piglets. The results showed that 28 d body weight exhibited linear and quadratic increases (P < 0.05) with increasing dietary XOS level, as well as average daily feed intake (ADFI) on d 15-28, average daily gain (ADG) on d 15-28 and 1-28. There was a linear decrease (P < 0.05) between XOS levels and feed conversion rate (FCR) on d 1-14 and 1-28. Additionally, glutathione peroxidase (GSH-Px) showed a linear increase (P < 0.05), while the malondialdehyde (MDA) level decreased linearly and quadratically (P < 0.05) with the increasing dietary level of XOS. Moreover, the XOS treatments markedly increased the levels of immunoglobulin A (Ig A) (linear, P < 0.05; quadratic, P < 0.05), IgM (quadratic, P < 0.05), IgG (linear, P < 0.05), and anti-inflammatory cytokine interleukin-10 (IL-10) (quadratic, P < 0.05) in serum, while the IL-1ß (linear, P < 0.05; quadratic, P < 0.05) and IL-6 (linear, P < 0.05) decreased with increasing level of XOS. Microbiota analysis showed that dietary supplementation with 1.5% XOS decreased (P < 0.05) the α-diversity and enriched (P < 0.05) beneficial bacteria including Lactobacillus, Bifidobacterium, and Fusicatenibacter at the genus level, compared with the control group. Importantly, linearly increasing responses (P < 0.05) to fecal acetate, propionate, butyrate, and total short-chain fatty acids (SCFAs) were observed with increasing level of XOS. Spearman correlation analyses found that Lactobacillus abundance was positively correlated with ADG, acetate, propionate, and IgA (P < 0.05), but negatively correlated with IL-1ß (P < 0.05). Bifidobacterium abundance was positively related with ADFI, total SCFAs, IgG, and IL-10 (P < 0.05), as well as g_Fusicatenibacter abundance with ADFI, total SCFAs, and IL-10. However, Bifidobacterium and Fusicatenibacter abundances were negatively associated with MDA levels (P < 0.05). In summary, dietary supplementation with XOS can improve the growth performance in weaning piglets by increasing antioxidant capability, enhancing immune function, and promoting beneficial bacteria counts.

Ingestion of xylooligosaccharides during the suckling period improve the feed efficiency and hindgut fermentation capacity of piglets after weaning.

Fiber ingestion during the suckling period is helpful for gut development and probiotic colonization. Xylooligosaccharides (Xos) and xylan (Xyl) were selected to investigate the effects of different polymerization degree fiber ingestion on the growth performance and microbiota fermentation capacity of pre- and post-weanling piglets. An in vitro fermentation trial was also conducted to verify the microbial fermentation capacity of weanling piglet fecal microbiota. Results showed that Xos and Xyl ingestion had no significant effect on the piglet body weight and D-lactate level in the plasma at 21 d during the suckling period. After weaning, piglets in the Xyl group had a lower average daily gain (ADG) (P < 0.05), vitro dry matter (DM) fermentability (P < 0.05) and activity of xylanase (P < 0.05) than the control and Xos groups. The Xos group had no significant difference in the ADG when compared with the control group, but a significantly lower feed conversion ratio (FCR) (P < 0.05) than the control group, which means a high feed efficiency in the Xos group. The highest carbohydrate digestion and absorption ability of fecal microbiota (P < 0.05) was found in the Xos group. Meanwhile, the Xos group had the highest butyrate production ability (P < 0.05) and activity of xylanase (P < 0.05) during in vitro fermentation. The ingestion of Xyl during the suckling period had negative effects on the feed efficiency and hindgut fermentation capacity of weanling piglets. Xylooligosaccharide ingestion to suckling piglets improves growth performance and feed efficiency after weaning through increasing the fermentation capacity of microbiota and fiber-degrading enzyme secretion.

Iodine monitoring models contribute to avoid adverse birth outcomes related more than adequate iodine intake.

BACKGROUND: Iodine plays an important role in pregnancy. How to maintain adequate iodine intake amongst pregnant women in each trimester of pregnancy to prevent adverse birth outcomes in central China is a challenge for clinical practice. METHODS: 870 pregnant women and their infants were enrolled in the study. Urinary iodine concentration (UIC) was measured using an inductively coupled plasma mass spectrometry (ICP-MS). Maternal and newborn information were obtained during follow-up. Multinomial logistic regression models were established. RESULTS: Median UIC of pregnant women was 172 ± 135 µg/L which is currently considered to be sufficient. Multivitamin supplements containing iodine, iodized salt intake and frequent milk intake were significantly associated with higher UIC. Multivariate logistic regression analysis showed that multivitamin supplements containing iodine and milk consumption were risk factors for more than adequate iodine (UIC ≥ 250 µg/L). Iodine-rich diet was significantly related to heavier birthweight, larger head circumference and longer femur length of the newborns while more than adequate iodine intake (UIC ≥ 250 µg/L) was a risk factor for macrosomia. Logistic regression models based on potential risk factors involving iodine containing supplements and iodine-rich diet were established to predict and screen pregnant women with high risk of more than adequate iodine intake among local pregnant women in different trimesters and guide them to supplement iodine reasonably to prevent the risk. CONCLUSIONS: Multivitamin supplements containing iodine and milk consumption were risk factors for maternal UIC ≥ 250 µg/L which was a risk factor for macrosomia. Iodine monitoring models were established to provide guidance for pregnant women to reduce the risk of more than adequate iodine intake, thereby contributing to reduce the risk of having a macrosomia.

In Vitro Fermentation Characteristics and Fiber-Degrading Enzyme Kinetics of Cellulose, Arabinoxylan, ß-Glucan and Glucomannan by Pig Fecal Microbiota.

Non-digestible polysaccharides are of great significance to human and animal intestinal health. Cellulose, arabinoxylan, ß-glucan and glucomannan were selected in the present study to investigate the fermentation characteristics and fiber-degrading enzyme kinetics by inoculating pig fecal microbiota in vitro. Our results showed that fermentation of arabinoxylan and ß-glucan produced the highest amount of acetate and lactate, respectively. The abundance of Prevotella_9 was the highest in ß-glucan group and positively correlated with lactate and acetate. Glucomannan fermentation produced the highest amount of butyrate, and the abundance of Lachnospiraceae_XPB_1014_group and Bacteroides were the lowest. A significant negative correlation was found between Lachnospiraceae_XPB_1014_group, Bacteroides and butyrate. Exo-ß-1,4-xylanase had the highest activity at 24 h during arabinoxylan fermentation. The activity of ß-glucosidase and ß-mannosidase at 36 h were higher than those at 15 h in the glucomannan group. The abundance of Prevotella_9 was positively correlated with ß-glucosidase while Lachnospiraceae_XPB_1014_group and Bacteroides were negatively correlated with ß-xylosidase. Our findings demonstrated the ß-glucan and arabinoxylan promote proliferation of Prevotella_9, with the preference to secret ß-glucosidase, ß-mannosidase and the potential to produce lactate and acetate. Butyrate production can be improved by inhibiting the proliferation of Lachnospiraceae_XPB_1014_group and Bacteroides, which have the lack of potential to secret ß-xylosidase.

Effects of metformin, insulin on COVID-19 patients with pre-existed type 2 diabetes: A multicentral retrospective study.

AIMS: Type 2 diabetes is considered to be one of the essential risks of adverse outcomes in coronavirus disease 2019 (COVID-19).1 Metformin and insulin were suggested to affect the outcomes. However, divergent views are still expressed. We aim to gain further insight into metformin and insulin in both pre-admission and in-hospital usage in COVID-19 patients with pre-existed type 2 diabetes. MAIN METHODS: This is a multicentral retrospective study of the hospital confirmed COVID-19 patients between January 19 to April 09, 2020, who admitted to 3 main hospitals in Xiangyang city, China. The effect of type 2 diabetes, metformin, and insulin on COVID-19 were analyzed, respectively. Clinical characteristics, blood laboratory indices, clinical observational indices, and outcomes of these cases were collected. KEY FINDINGS: A total of 407 confirmed COVID-19 patients (including 50 pre-existed type 2 diabetes) were eligible in our study. COVID-19 patients with type 2 diabetes had more adverse outcomes than non-diabetes (OR2: mortality: 1.46 [95% CI3 1.11, 1.93]; P < 0.001). Pre-admission metformin usage showed a declined intensive care unit admission rate in a dose-dependent fashion (OR 0.04 [95% CI 0.00, 0.99]; adjust P = 0.049). While in-hospital insulin usage attempted to increase the invasive ventilation (8 [34.8%] vs. 1 [3.7%], adjust P = 0.043), independent of age and blood glucose. SIGNIFICANCE: Our study indicated that pre-admitted metformin usage may have beneficial effects on COVID-19 with pre-existed type 2 diabetes, insulin should be used sparingly in the hospital stay.

Sources of Dietary Fiber Affect the SCFA Production and Absorption in the Hindgut of Growing Pigs.

Effects of different dietary fiber (DF) sources on short-chain fatty acids (SCFA) production and absorption in the hindgut of growing pigs were studied by an in vivo-vitro (ileal cannulated pigs and fecal inoculum-based fermentation) method. Thirty-six cannulated pigs (body weight: 48.5 ± 2.1 kg) were randomly allocated to 6 treatments containing the same DF content (16.5%), with either wheat bran (WB), corn bran (CB), sugar beet pulp (SBP), oat bran (OB), soybean hulls (SH), or rice bran (RB) as DF sources. Pigs were allowed 15 days for diet adaptation, and then, fresh ileal digesta and feces were collected to determine SCFA concentration which was normalized for food dry matter intake (DMI) and the hindgut DF fermentability. Fecal microbiota was inoculated into the freeze-dried ileal digesta samples to predict the ability of SCFA production and absorption in the hindgut by in vitro fermentation. The SH group had the largest concentration of total SCFA and propionate in ileal digesta and fecal samples of growing pigs (p < 0.05). Nonetheless, the predicted acetate, total SCFA production, absorption in the SBP group were the highest (p < 0.01), but the lowest in the OB group (p < 0.01) among all groups. Even SBP and OB group had a similar ratio of soluble DF (SDF) to insoluble DF (IDF). The CB group had high determined ileal and fecal butyrate concentration but the lowest butyrate production and absorption in the hindgut (p < 0.01). Overall, the source of DF had a great impact on the hindgut SCFA production and absorption, and SBP fiber had a great potential to increase hindgut SCFA production and absorption.

Effect of dietary fiber fermentation on short-chain fatty acid production and microbial composition in vitro.

BACKGROUND: The efficient utilization of fiber-rich co-products is important for optimizing feed resource utilization and animal health. This study was conducted to evaluate the fermentation characteristics of fiber-rich co-products, which had equal quantities of total dietary fiber (TDF), at different time points using batch in vitro methods. It considered their gas production, short-chain fatty acid (SCFA) production, and microbial composition. RESULTS: The fermentation of wheat bran (WB) and oat bran (OB) showed higher and faster (P < 0.05) gas and SCFA production than corn bran (CB), sugar beet pulp (SBP), and soybean hulls (SH). The α-diversity was higher in the CB, SBP, and SH groups than in the WB and OB groups (P < 0.05). At the phylum level, OB and WB fermentation showed lower (P < 0.05) relative abundance of Actinobacteria than the CB, SBP, and SH groups. At the genus level, OB and WB fermentation increased the Enterococcus population in comparison with the CB, SBP, and SH groups, whereas CB and SBP fermentation improved the relative abundance of the Christensenellaceae R-7 group more than the WB, OB, and SH groups (P < 0.05). CONCLUSION: Overall, WB and OB were rapidly fermented by fecal microbiota, in contrast with SBP, SH, and CB. Fermentation of different fiber-rich co-products with an equal TDF content gives different responses in terms of microbial composition and SCFA production due to variations in their physicochemical properties and molecular structure. © 2020 Society of Chemical Industry.

In Vitro Fermentation Characteristics for Different Ratios of Soluble to Insoluble Dietary Fiber by Fresh Fecal Microbiota from Growing Pigs.

This study was conducted to explore the in vitro fermentation characteristics for different ratios of soluble to insoluble dietary fiber in pig fecal microbiota. The fermentation substrates consisted of inulin and a non-starch polysaccharide mixture and were divided into five groups according to different soluble dietary fiber (SDF) to insoluble dietary fiber (IDF) ratios (SDF 25, 50, 75, and 100%). With the increased SDF ratio, the total gas production increased, and the pH in the substrate decreased as the fermentation proceeded. The concentrations of lactic acid, formic acid, and acetic acid increased in the high SDF ratio group, whereas the concentrations of propionic acid and butyric acid increased in the low SDF ratio group. The genera Clostridium_sensu_stricto_1, Ruminococcaceae_NK4A214_group, Christensenellaceae_R-7_group, and Rikenellaceae_RC9_gut_group were enriched in the high SDF ratio group. Correlation analysis indicated that these differential bacteria had the potential to degrade polysaccharides. These results revealed that high SDF ratios could stimulate the proliferation of fibrolytic bacteria, which in turn degrade fibers to produce organic acids and monosaccharides. Collectively, these findings add to our understanding of the mechanisms responsible for interaction between SDF and intestinal microbiota and provide new ideas for the rational use of dietary fiber.

Determination of chemical composition, energy content, and amino acid digestibility in different wheat cultivars fed to growing pigs.

This study was conducted to determine the DE, ME, and apparent (AID) and standardized ileal digestibility (SID) of AA in different wheat cultivars fed to growing pigs. In Exp. 1, twelve crossbred growing barrows were allotted to a replicated 6 × 6 Latin square design to determine the DE and ME contents of 12 different wheat cultivars. In Exp. 2, twelve growing barrows with a simple T-cannula were used to determine the AID and SID of AA in 10 different wheat cultivars. Pigs were randomly allotted to a replicated 6 × 6 Latin square design and fed one nitrogen-free diet and 10 different cultivars of wheat diets. Among different wheat cultivars, the concentrations of GE, CP, NDF, ADF, and starch ranged from 4,385 to 4,458 kcal/kg, 12.95% to 18.14%, 9.16% to 13.89%, 1.93% to 2.92% and 60.81% to 70.77%, respectively (DM basis). There were significant differences (P < 0.05) in the DE, ME values, and the ATTD of GE in 12 different cultivars of wheat in Exp. 1. The DE and ME contents and the ATTD of GE ranged (P < 0.05) from 3,922 to 4,067 kcal/kg DM, 3,759 to 3,941 kcal/kg DM and 88.14% to 90.31%, respectively. The best prediction equations of DE and ME for different cultivars of wheat cultivars were DE = -2,738 - (40.8 × % ADF) + (1.7 × GE) - (51.5 × % Xylans) - (95.7 × % Ash) + (22.3 × % EE), R2 = 0.98, and ME = -2,990 + (1.7 × GE) - (50.2 × % Xylans) - (87.6 × % Ash), R2 = 0.88, respectively. There were also differences (P < 0.05) in the AID and SID of CP and indispensable AA, expect for His, in 10 wheat cultivars in Exp. 2. The AID and SID of CP, Lys, and Met ranged (P < 0.05) from 82.02% to 89.46%, 74.13% to 84.73%, 87.35% to 92.49% and 87.56% to 94.04%, 80.56% to 89.89%, 89.56% to 94.45%, respectively. In conclusion, the chemical composition, energy contents, and most AA digestibility in different cultivars of wheat varied widely.