Study on the Mechanism of Action of the Traditional Chinese Medical Prescription Gushukang in Treating Osteoporosis Based on Network Pharmacology and Experimental Verification.

BACKGROUND: Gushukang (GSK), a traditional Chinese medical prescription, has made a great and extensive contribution to the treatment of different forms of osteoporosis, but polypharmacology studies of its mechanism of action are lacking. This study investigates the pharmacological mechanism of osteoporosis using network pharmacology and molecular docking. Experimental verification was carried out to confirm the efficacy of GSK on RANKLinduced osteoclast differentiation in RAW264.7 cells to verify the network pharmacology studies. METHODS: The effective chemical components and corresponding targets of osteoporosis with oral bioavailability of more than 30% and drug-like properties greater than 0.18 were searched in the TCMSP and TCM-ID databases. DrugBank, GeneCards, OMIM, TTD, and other databases were examined for targets related to osteoporosis. Using Cytoscape software, a network of possible TCM-active ingredient-osteoporosis targets was created. STRING software was used to create the networks of protein-protein interactions. The DAVID program was carried out to conduct GO and KEGG pathway enrichment analyses of the targets. Molecular docking and pattern of action analysis were carried out using software like AutoDock Vina and Discovery Studio Visualizer. The growth media for RAW264.7 cells contained varying doses of GSK serum and 50 ng/mL RANKL. The activity of TRAP was altered. Additionally, genes related to osteoclasts were examined using an RT-PCR assay. RESULTS: Network pharmacological analysis revealed that the primary efficacy targets of osteoporosis were PTGS2, PTGS1, HSP90AA1, NCOA2, ADRB2, ESR1, NCOA1, and AR. The pharmacological targets of osteoporosis may be mediated by substances including quercetin, kaempferol, luteolin, naringenin, icariin, anthocyanin, tanshinone IIA, and cryptotanshinone. GSK markedly inhibited RANKL-induced TRAP activity. qRT-PCR results revealed decreased expression of the PTGS2 and ADRB2 genes upon GSK treatment. CONCLUSION: The findings of network pharmacology, molecular docking, as well as experimental verification provide a new further study for elucidating the pharmacodynamic substance basis and polypharmacology mechanism of GSK in treating osteoporosis.

Gratitude practice helps undergraduates who experienced an earthquake in China find meaning in life.

This study was conducted following a magnitude 6.8 earthquake that occurred in early September 2022, coinciding with the commencement of a positive psychology course for the affected students. A sample of 479 Chinese undergraduates was recruited for an intervention focused on weekly gratitude practice. Data were collected through an online questionnaire package at 3 time points: the first week of the course (Time 1), the fifth week (Time 2), and the ninth week (Time 3), assessing gratitude, learning engagement, and the meaning of life. Findings revealed that gratitude significantly predicted meaning in life through learning engagement over time. This highlights the significant mediating role of learning engagement in the context of earthquakes and provides insights for positive interventions aimed at facilitating personal growth among emerging adults in higher educational settings, particularly those who have experienced traumatic events such as earthquakes.

Safety, tolerability, and pharmacokinetics of mitoxantrone hydrochloride injection for tracing in patients with gastric cancer: a single-blind, single-center, phase I clinical trial.

Mitoxantrone Hydrochloride Injection for Tracing (MHI), a modified new drug marketed in China, has been approved by the National Medical Products Administration for lymph node tracing in thyroid cancer and sentinel lymph node biopsy in breast cancer. This single-center, single-blind, dose-escalation phase I clinical trial aimed to investigate the safety of MHI on lymph node tracing in gastric cancer. In this study, four dose groups (1.0 mL, 1.5 mL, 2.0 mL, and 3.0 mL) with 3 gastric cancer patients in each group were set. The safety, tolerability, pharmacokinetics and preliminary efficacy of different doses were investigated. Results showed that none of the patients experienced dose-limiting toxicity or developed serious adverse events or adverse drug reactions. Pharmacokinetic analyses revealed minimal absorption of the tracer, resulting in low and transient blood drug concentrations across all participants. The mean time to peak concentration was (0.561 ± 0.3728) h (with mean peak concentration (Cmax) of 10.300 ng/mL), (0.500 ± 0.0167) h (mean Cmax of 13.687 ng/mL), (0.494 ± 0.0096) h (mean Cmax of 30.933 ng/mL), and (0.661 ± 0.2791) h (mean Cmax of 21.067 ng/mL) in the 1.0 mL, 1.5 mL, 2.0 mL, and 3.0 mL dose groups, respectively. The mean lymph node staining rates were 21.0%, 24.7%, 32.5%, and 44.5%, and the mean metastatic lymph node staining rates were 20.6%, 36.1%, 42.4%, and 21.0% in each group. This study confirmed that MHI was safe, well-tolerated, and had low systemic effects when used for lymphatic tracing of gastric cancer, and the tracing effect was better in the 3 mL dose group. This trail was registered on the website of Centre for Drug Evaluation State Drug and Food Administration (http://www.chinadrugtrials.org.cn/index.html) with the name of clinical study of lymphatic tracer in lymph node tracing of gastric cancer, the code was CTR20201906.

Borneol regulates meningeal lymphatic valve plasticity to clear Aß aggregates in the prevention of AD-like symptoms.

BACKGROUND: Meningeal lymphatic vessels (mLVs) have great potential to be the therapeutic target for ß Amyloid protein (Aß) clearing in Alzheimer's disease (AD), but the regulatory methods of the mLVs are limited. The lymphatic valve, marked by FOXC2, is the fundamental structure for maintaining stable lymphatic drainage function. Preliminary evidence suggested that borneol (BO) as the classical phytochemicals could enhance the expression of FOXC2 in the mLVs of healthy mice. PURPOSE: This study aims to explore the regulatory ability of BO on lymphatic valves of mLVs in the AD model mice. STUDY DESIGN: We used the intracerebroventricular injection of Aß42 oligomers to construct the AD-like symptoms model induced by toxic protein deposition. We administered BO nano micelles(BO-Ms) orally before and after to simulate the AD prevention and treatment strategy. METHODS: Herein, this study characterized the efficacy and pathways of BO-Ms for regulating mLVs in AD model by Rt-PCR, WB and confocal microscopy, and determined the effects of BO-Ms on Aß clearance, behavior and safety of AD mice. RESULTS: The AD modeling process severely impaired the expression of lymphatic valves. However, after oral administering BO-Ms for prevention and treatment, an increase in the lymphatic valves of the transverse sinus was observed, which derived from the up-regulation of the transcription factor (FOXC2 and Akt) and the down-regulation of the transcription inhibitors (FOXO1 and PRDM1). Furthermore, the effects of BO-Ms on the lymphatic valves could enhance the lymphatic drainage of the mLVs in AD-like mice, promoting the clearance of toxicity aggregates, protecting neurons, and alleviating AD-like symptoms. Simultaneously, continuous oral BO-Ms for 30 days didn't show any significant organ toxicity. The most important thing was that the preventive effect of BO administration was superior to therapeutic administration in all data. CONCLUSION: In summary, our research indicated that BO is a promoter of lymphatic valve formation in the mLVs, and could prevent or repair damage caused by toxic Aß42. BO was the only bioactive natural product with the ability to regulate mLVs valves. Thus, BO has the potential to become phytochemicals for alleviating AD symptoms by enhancing the drainage function of mLVs.

Novel Angiotensin-Converting Enzyme-Inhibitory Peptides Obtained from Trichiurus lepturus: Preparation, Identification and Potential Antihypertensive Mechanism.

Peptides possessing antihypertensive attributes via inhibiting the angiotensin-converting enzyme (ACE) were derived through the enzymatic degradation of Trichiurus lepturus (ribbonfish) using alkaline protease. The resulting mixture underwent filtration using centrifugation, ultrafiltration tubes, and Sephadex G-25 gels. Peptides exhibiting ACE-inhibitory properties and DPPH free-radical-scavenging abilities were isolated and subsequently purified via LC/MS-MS, leading to the identification of over 100 peptide components. In silico screening yielded five ACE inhibitory peptides: FAGDDAPR, QGPIGPR, IFPRNPP, AGFAGDDAPR, and GPTGPAGPR. Among these, IFPRNPP and AGFAGDDAPR were found to be allergenic, while FAGDDAPRR, QGPIGPR, and GPTGPAGP showed good ACE-inhibitory effects. IC50 values for the latter peptides were obtained from HUVEC cells: FAGDDAPRR (IC50 = 262.98 µM), QGPIGPR (IC50 = 81.09 µM), and GPTGPAGP (IC50 = 168.11 µM). Peptide constituents derived from ribbonfish proteins effectively modulated ACE activity, thus underscoring their therapeutic potential. Molecular docking and modeling corroborated these findings, emphasizing the utility of functional foods as a promising avenue for the treatment and prevention of hypertension, with potential ancillary health benefits and applications as substitutes for synthetic drugs.

A Feasibility Study on Using Hanging Arm Test to Assess Elbow Stability During Surgical Treatment for Varus Posteromedial Rotatory Instability.

Objectives: The aim of this study to investigate the safety and effectiveness of performing the hanging arm test during surgical treatment for elbow varus posteromedial rotatory instability (VPMRI) to assess elbow stability and determine whether to repair the lateral ulnar collateral ligament (LUCL). Methods: In a retrospective study from August 2014 to March 2019, 27 patients with VPMRI who had a negative result in the hanging arm test after fixation of coronoid fracture were selected. Intraoperative bleeding, operative time, elbow range of motion (ROM), and complications were recorded. Elbow function was evaluated with the Mayo elbow performance score (MEPS) and the disabilities of the arm, shoulder, and hand (DASH) score. Results: The operation time was 85.9 ± 11.06 min (range 65-110). The intraoperative blood loss was 70.7 ± 9.31 ml (range 60-100). At the last follow-up, the elbow joint averaged 73.8° ± 2.931° in pronation, 78.9° ± 2.941° in supination, 7.2° ± 3.207° in extension, and 123.3° ± 6.651° in flexion. The MEPS score was 90.7 ± 4.36 (range 74-95), and the DASH score was 9.8 ± 2.58 (range 6.67-13.3). One patient presented with symptoms of ulnar nerve entrapment 2 months after operation and was treated with ulnar nerve release. The symptom of numbness went away completely 1 week after operation. No complications such as wound infection, arthritis, or chronic instability of the elbow were found in the other patients. Conclusion: Our findings suggest that not all VPMRI patients need the LUCL to be repaired, and the hanging arm test is a safe and reliable method to assess whether to repair the LUCL in the treatment of elbow VPMRI. Level of evidence: Level IV; Retrospective studies.

Physiological, Metabolic, and Transcriptomic Analyses Reveal Mechanisms of Proliferation and Somatic Embryogenesis of Litchi (Litchi chinensis Sonn.) Embryogenic Callus Promoted by D-Arginine Treatment.

D-arginine (D-Arg) can promote embryogenic callus (EC) proliferation and increase the rate of somatic embryo induction of litchi (Litchi chinensis Sonn.), yet the mechanism underlying the processes is incompletely understood. To investigate the mechanism, physiological responses of polyamines (PAs) [putrescine (Put), spermidine (Spd), and spermine (Spm)] were investigated for D-Arg-treated litchi EC and enzyme activity related to polyamine metabolism, plant endogenous hormones, and polyamine- and embryogenic-related genes were explored. Results showed that the exogenous addition of D-Arg reduces the activity of diamine oxidase (DAO) and polyamine oxidase (PAO) in EC, reduces the production of H2O2, promotes EC proliferation, and increases the (Spd + Spm)/Put ratio to promote somatic embryo induction. Exogenous D-Arg application promoted somatic embryogenesis (SE) by increasing indole-3-acetyl glycine (IAA-Gly), kinetin-9-glucoside (K9G), and dihydrozeatin-7-glucoside (DHZ7G) levels and decreasing trans-zeatin riboside (tZR), N-[(-)-jasmonoyl]-(L)-valine (JA-Val), jasmonic acid (JA), and jasmonoyl-L-isoleucine (Ja-ILE) levels on 18 d, as well as promoting cell division and differentiation. The application of exogenous D-Arg regulated EC proliferation and somatic embryo induction by altering gene expression levels of the WRKY family, AP2/ERF family, C3H family, and C2H2 family. These results indicate that exogenous D-Arg could regulate the proliferation of EC and the SE induction of litchi by changing the biosynthesis of PAs through the alteration of gene expression pattern and endogenous hormone metabolism.

Interfacial galvanic replacement strategy for Pd-doped NiFe MOF nanosheets with highly efficient dopamine detection.

An interfacial galvanic replacement strategy to controllable synthesize palladium nanoparticles (Pd NPs)-modified NiFe MOF nanocomposite on nickel foam, which served as an efficient sensing platform for quantitative determination of dopamine (DA). Pd NPs grown in situ on the nanosheets of NiFe MOF via self-driven galvanic replacement reaction (GRR) and well uniform distribution was achieved. This method effectively reduced the aggregation of metallic nanoparticles and significantly promoted the electron transfer rate during the electrochemical process, leading to improved electrocatalytic activity for DA oxidation. Remarkably, the precisely constructed biosensor achieved a low detection limit (LOD) of 0.068 µM and recovery of 94.1% (RSD 6.7%, N = 3) for simulated real sample detection and also exhibited superior selectivity and stability. The results confirmed that the as-fabricated Pd-NiFe/NF composite electrode could realize the quantitative determination of DA and showed promising prospects in real sample biosensing.

Novel Type of Slowly Digested Starch Complex with Antioxidant Properties.

With the increasing number of diabetic patients in the world, there is an urgent requirement to reduce the incidence of diabetes. It is considered that a viable prophylactic treatment for type 2 diabetes mellitus is to reduce starch digestibility and oxidative stress. In this study, a novel type of slowly digested starch [pea starch (PS)-gingerol complex] was fabricated to evaluate its in vitro enzymatic digestibility and antioxidant activities. Theoretical and experimental analyses showed that PS can encapsulate gingerols with long alkyl chains to form starch-gingerol complexes, which are further stacked into a mixture of V6- and V7-crystallites. These complexes, in particular the PS-10-gingerol complex, showed high resistance to amylolysis and good antioxidant activities. This study demonstrates that these novel starch-gingerol complexes have the potential to deliver antioxidants encapsulated in starch with slow-digesting properties and reduce oxidative stress. Moreover, this new type of slowly digested starch with antioxidant properties showed great potential in the prevention of type 2 diabetes.

The double roles of T cell-mediated immune response in the progression of MASLD.

Metabolic dysfunction-associated steatotic liver disease(MASLD), formerly known as non-alcoholic fatty liver disease(NAFLD), has become a major cause of chronic liver disease and a significant risk factor for hepatocellular carcinoma, which poses a huge burden on global public health and economy. MASLD includes steatotic liver disease, steatohepatitis, and cirrhosis, and the latter two cause great harm to human health and life, even complicated with liver cancer. Immunologic mechanism plays a major role in promoting its development into hepatitis and cirrhosis. Now more and more evidences show that T cells play an important role in the progression of MASLD. In this review, we discuss the double roles of T cells in MASLD from the perspective of T cell response pathways, as well as new evidences regarding the possible application of immunomodulatory therapy in MASH.

Enrofloxacin Rapid Detection in Aquatic Foods: Based on DNA Aptamer Sensor.

Enrofloxacin (ENR) is widely used as a synthetic fluoroquinolone antibiotic for disease control in aquatic animals. ENR aptamers were screened in this study using the magnetic bead-SELEX method, and a graphene oxide fluorescent sensor was developed to detect the ENR residues in aquatic products. Firstly, ENR was conjugated to amino magnetic beads by amidation reaction, and then the aptamer sequences showing high affinity to ENR were screened step by step by using the SELEX screening method. Finally, after 10 rounds of SELEX screening, six candidate aptamers with high affinity were obtained. Among these, ENR-Apt 6 was selected based on its secondary structure features, high affinity (Kd = 35.08 nM), and high specificity to ENR. Furthermore, a fluorescent sensor was prepared using graphene oxide and ENR-Apt 6. The results showed that the linear range of the sensor could reach 600 nM (R2 = 0.986), while its optimal linear range was 1-400 nM (R2 = 0.991), with the lowest detection limit of 14.72 nM. The prepared sensor was successfully used for the detection of ENR in real samples, with a recovery range of 83.676-114.992% and a relative standard deviation < 10% for most of the samples.

An electrochemiluminescence sensor based on lanthanide bimetallic MOFs with a "cascade sensitization mechanism" for the sensitive detection of CA242.

Lanthanide metal-organic frameworks (Ln-MOFs) broaden the optical sensing applications of lanthanide ions due to the antenna effect between organic ligands and metals. However, the sensitization ability of the ligand to metal ions is limited, and maximizing the sensitization of the electrochemiluminescence behavior of Eu3+ is still a challenge for the application of Ln-MOFs. Therefore, under the guidance of the "cascade sensitization mechanism" based on the antenna effect sensitizing the electrochemiluminescence of bimetallic Ln-MOFs, we proposed Eu/Tb-MOFs with high luminescence intensity as a signal probe. According to the antenna effect, the conjugated structure and high extinction coefficient of the benzene ring of 2-amino terephthalic acid (NH2-BDC) can enhance the ECL luminescence intensity of Eu/Tb-MOFs. Tb3+ can act as an energy bridge between NH2-BDC and Eu3+, buffering the energy gap. The bimetallic sensitization is formed between Tb3+ and Eu3+, which can inhibit the reverse internal flow of energy and ensure the high luminous efficiency of Eu3+. In addition, the nanosphere mixed valence Fe3O4 as a co-reactant accelerator promotes the formation of transient free radical SO4•- through the valence change of Fe2+/Fe3+. The ECL immunosensor constructed by luminophores Eu/Tb-MOFs and nanosphere Fe3O4 provided a new explanation for the ECL self-luminous of Eu/Tb-MOFs.

A novel method for quantifying the short-range order in non-crystalline starch by Raman spectroscopy.

A quantitative method was developed to characterize the short-range order in non-crystalline starch by Raman spectroscopy. The Raman spectra of three forms of non-crystalline starches (just-gelatinized starch, which was heated to the point of having just lost its long-range order but still retaining essentially all of its short-range order, gelatinized starch and amorphous starch) were resolved into subspectra to calculate the short-range ordered phases. By deducting the spectra of amorphous starch using a subtraction technique, the areas of subspectra for short-range ordered phases in just-gelatinized and gelatinized starches were obtained. The ratio of the area for short-range ordered phases in gelatinized starch relative to that in just-gelatinized starch was negatively correlated with water content for gelatinization. Based on this, we propose that this ratio of areas provides a quantitative measure for assessing the short-range order in non-crystalline starch. This study provides an alternative and simpler method to an X-ray diffraction protocol proposed previously.

An ultrasensitive electrochemical immunosensor based on meso-PdN NCs and Au NPs/N-CNTs for quantitative cTnI detection.

Electrochemical immunosensors have gained considerable attention in detecting human disease markers due to their excellent specificity, high sensitivity, and facile operation. Herein, a rational-designed sandwich-type electrochemical immunosensor is constructed for the sensitive detection of cardiac troponin I (cTnI) using nitrogen-doped carbon nanotubes loaded with gold nanoparticles (Au NPs/N-CNTs) as substrate and highly active mesoporous palladium-nitrogen nanocubes (meso-PdN NCs) as secondary antibody markers. Benefitting from its large specific surface area (638.04 m2 g-1) and high nitrogen content, novel polydopamine (PDA)/ halloysite nanotubes (HNTs) hybrid derived one-dimensional (1D) N-CNTs can provide more binding sites for the in-situ growth of Au NPs to connect Ab1. Furthermore, as an ideal substrate material, Au NPs/N-CNTs exhibit finely tuned mesoporous structures and outstanding conductivity, which facilitate the mass and electron transfer during the electrocatalysis process. Besides, highly concave surfaces and crystalline mesopores of meso-PdN NCs expose more surfaces and crevices, providing abundant reactive sites for H2O2 reduction. Remarkably, the as-obtained immunosensor presented a wide linear range (from 10 fg mL-1 to 100 ng mL-1) and an excellent low detection limit (9.85 fg mL-1). This study may offer new insights into the precise fabrication of efficient electrochemical immunosensors for various clinical diagnosis applications.

Aptamer-Based Sensor for Rapid and Sensitive Detection of Ofloxacin in Meat Products.

Ofloxacin (OFL) is widely used in animal husbandry and aquaculture due to its low price and broad spectrum of bacterial inhibition, etc. However, it is difficult to degrade and is retained in animal-derived food products, which are hazardous to human health. In this study, a simple and efficient method was developed for the detection of OFL residues in meat products. OFL coupled with amino magnetic beads by an amination reaction was used as a stationary phase. Aptamer AWO-06, which showed high affinity and specificity for OFL, was screened using the exponential enrichment (SELEX) technique. A fluorescent biosensor was developed by using AWO-06 as a probe and graphene oxide (GO) as a quencher. The OFL detection results could be obtained within 6 min. The linear range was observed in the range of 10-300 nM of the OFL concentration, and the limit of the detection of the sensor was 0.61 nM. Furthermore, the biosensor was stored at room temperature for more than 2 months, and its performance did not change. The developed biosensor in this study is easy to operate and rapid in response, and it is suitable for on-site detection. This study provided a novel method for the detection of OFL residues in meat products.

New Insight into the Effects of Endogenous Protein and Lipids on the Enzymatic Digestion of Starch in Sorghum Flour.

The effects of endogenous lipids and protein in sorghum flour on starch digestion were studied following the depletion of lipids and/or protein and after the reconstitution of separated fractions. The removal of protein or lipids moderately increases the digestibility of starch in raw (uncooked) sorghum flour to values close to those for purified starch. Rapid Visco Analyzer data (as a model for the cooking process) show that cooked sorghum flours with lipids have a lower starch digestibility than those without lipids after RVA processing, due to the formation of starch-lipid complexes as evidenced by their higher final viscosity and larger enthalpy changes. Additionally, the formation of a starch-lipid-protein ternary complex was identified in cooked sorghum flour, rather than in a reconstituted ternary mixture, according to the unique cooling stage viscosity peak and a greater enthalpy of lipid complexes. After heating, the sorghum flour showed a lower digestibility than the depleted flours and the reconstituted flours. The results indicate that the natural organization of components in sorghum flour is an important factor in facilitating the interactions between starch, lipids, and protein during RVA processing and, in turn, reducing the starch digestion.

Preparation of Sweet Potato Porous Starch by Marine Dextranase and Its Adsorption Characteristics.

Dextranase (EC 3.2.1.11) is primarily applied in food, sugar, and pharmaceutical industries. This study focuses on using a cold shock Escherichia coli expression system to express marine dextranase SP5-Badex; enzyme activity increased about 2.2-fold compared to previous expression. This enzyme was employed to produce sweet potato porous starch, with special emphasis on the pore size of the starch. The water and oil adsorption rates of the porous starch increased by 1.43 and 1.51 times, respectively. Extensive Fourier transform infrared spectroscopy and X-ray diffraction revealed that the crystal structure of the sweet potato starch was unaltered by enzymatic hydrolysis. The adsorption capacities of the porous starch for curcumin and proanthocyanidins were 9.59 and 12.29 mg/g, respectively. Notably, the stability of proanthocyanidins was significantly enhanced through their encapsulation in porous starch. After 2.5 h of ultraviolet irradiation, the free radical scavenging rate of the encapsulated proanthocyanidins remained at 95.10%. Additionally, after 30 days of sunlight exposure, the free radical scavenging rate of the encapsulated proanthocyanidins (84.42%) was significantly higher than that (24.34%) observed in the control group. These research findings provide substantial experimental evidence for preparing sweet potato porous starch using marine dextranase.

The Screening and Identification of a Dextranase-Secreting Marine Actinmycete Saccharomonospora sp. K1 and Study of Its Enzymatic Characteristics.

In this study, an actinomycete was isolated from sea mud. The strain K1 was identified as Saccharomonospora sp. by 16S rDNA. The optimal enzyme production temperature, initial pH, time, and concentration of the inducer of this actinomycete strain K1 were 37 °C, pH 8.5, 72 h, and 2% dextran T20 of medium, respectively. Dextranase from strain K1 exhibited maximum activity at 8.5 pH and 50 °C. The molecular weight of the enzyme was <10 kDa. The metal ions Sr2+ and K+ enhanced its activity, whereas Fe3+ and Co2+ had an opposite effect. In addition, high-performance liquid chromatography showed that dextran was mainly hydrolyzed to isomaltoheptose and isomaltopentaose. Also, it could effectively remove biofilms of Streptococcus mutans. Furthermore, it could be used to prepare porous sweet potato starch. This is the first time a dextranase-producing actinomycete strain was screened from marine samples.

Molecular Mechanisms Underlying the Effects of Small Intestinal Fermentation on Enhancement of Prebiotic Characteristics of Cellulose in the Large Intestine.

Knowledge about the prebiotic characteristics of cellulose by in vitro fermentation is not complete due to the neglect of small intestinal fermentation. This study investigated the effects of small intestinal fermentation on the prebiotic characteristics of cellulose in the large intestine and potential mechanisms through an approach of combined in vivo small intestinal fermentation and in vitro fermentation. The structural similarity between cellulose in feces and after processing by the approach of this study confirmed the validity of the approach employed. Results showed that small intestinal fermentation of cellulose increased both acetate and propionate content and enriched Corynebacterium selectively. Compared to in vitro fermentation after in vitro digestion of cellulose, the in vitro fermentation of cellulose after in vivo small intestinal fermentation produced higher contents of acetate and propionate as well as the abundance of probiotics like Ruminococcaceae_UCG-002, Blautia, and Bifidobaterium. The changes in the structural features of cellulose after in vivo small intestinal fermentation were more obvious than those after in vitro digestion, which may account for the greater production of short-chain fatty acids (SCFAs) and the abundance of probiotics. In summary, small intestinal fermentation enhanced the prebiotic characteristics of cellulose in the large intestine by predisrupting its structure.

The influence of short-range molecular order in gelatinized starch on the formation of starch-lauric acid complexes.

A model system of gelatinized wheat starch (GWS) and lauric acid (LA) was used to examine the effect of residual short-range molecular order in GWS on the formation of starch-lipid complexes. The extent of residual short-range molecular order, as determined by Raman spectroscopy, decreased with increasing water content or heating duration of gelatinization. The enthalpy changes, crystallinity, short-range molecular order and the in vitro enzymic digestion of GWS-LA complexes increased initially to a maximum and then declined as the short-range molecular order in GWS decreased, showing that there was an optimal amount of residual short-range molecular order in GWS for maximizing GWS-LA complexes formation. Below this optimum amount, the limited disruption of short-range molecular order may constrain the mobility of amylose chains for complexation with LA, whereas with excessive disruption above this amount the amylose chains may be too disorganized or entangled to form complexes with LA. The susceptibility of GWS-LA complexes to enzymatic hydrolysis was influenced by both long- and short-range structural order, and to a lesser extent the amounts of complexes. This study showed clearly the role of short-range molecular order in gelatinized starch in influencing the formation of GWS-LA complexes.