Effect of steam explosion pretreatment on the fermentation characteristics of polysaccharides from tea residue.

Green tea residues are the by-product of tea processing and they contain a large number of bioactive ingredients. Steam explosion has been recognized as one of the most innovative pretreatments for modifying the physicochemical characteristic of polysaccharides from lignocellulosic materials. However, the comparison of biological activity of steam exploded (SE-GTR) and unexploded (UN-GTR) green tea residue polysaccharides was still unclear, which prompted the determination of the efficacy of steam explosion in tea residue resource utilization. In this study, the effects of two extracted polysaccharides UN-GTR and SE-GTR on human gut microbiota in vitro fermentation were conducted. The results showed that after steam explosion pretreatment, SE-GTR displayed more loose and porous structures, resulting in higher polysaccharide content (2483.44±0.5 µg/mg) compared to UN-GTR (1903.56±2.6 µg/mg). In addition, after 24 h fermentation, gut microbiota produced more beneficial metabolites by SE-GTR. The largest SCFAs produced among samples was acetic acid, propionic acid and butyric acid. Furthermore, SE-GTR could regulate the composition and diversity of microbial community, increasing the abundance of beneficial bacteria, such as Bifidobacterium. These results revealed that steam explosion pretreatment could be a promising and efficient approach to enhance the antioxidant activity and bioavailability of polysaccharides isolated from tea residues.

Obesity enhances the response to neoadjuvant anti-PD1 therapy in oral tongue squamous cell carcinoma.

OBJECTIVES: Previous studies have demonstrated that obesity may impact the efficacy of anti-PD1 therapy, but the underlying mechanism remains unclear. In this study, our objective was to determine the prognostic value of obesity in patients with oral tongue squamous cell carcinoma (OTSCC) treated with pembrolizumab and establish a subtype based on fatty acid metabolism-related genes (FAMRGs) for immunotherapy. MATERIALS AND METHODS: We enrolled a total of 56 patients with OTSCC who underwent neoadjuvant anti-PD1 therapy. Univariate and multivariate Cox regression analyses, Kaplan-Meier survival analysis, and immunohistochemistry staining were performed. Additionally, we acquired the gene expression profiles of pan-cancer samples and conducted GSEA and KEGG pathway analysis. Moreover, data from TCGA, MSigDB, UALCAN, GEPIA and TIMER were utilized to construct the FAMRGs subtype. RESULTS: Our findings indicate that high Body Mass Index (BMI) was significantly associated with improved PFS (HR = 0.015; 95% CI, 0.001 to 0.477; p = 0.015), potentially attributed to increased infiltration of PD1 + T cells. A total of 91 differentially expressed FAMRGs were identified between the response and non-response groups in pan-cancer patients treated with immunotherapy. Of these, 6 hub FAMRGs (ACSL5, PLA2G2D, PROCA1, IL4I1, UBE2L6 and PSME1) were found to affect PD-1 expression and T cell infiltration in HNSCC, which may impact the efficacy of anti-PD1 therapy. CONCLUSION: This study demonstrates that obesity serves as a robust prognostic predictor for patients with OTSCC undergoing neoadjuvant anti-PD1 therapy. Furthermore, the expression of 6 hub FAMRGs (ACSL5, PLA2G2D, PROCA1, IL4I1, UBE2L6 and PSME1) plays a pivotal role in the context of anti-PD1 therapy and deserves further investigation.

In vitro fermentation characteristics of polysaccharides from coix seed and its effects on the gut microbiota.

Coix seed polysaccharides had received increasing attention due to their diverse biological activities. In this study, a homogeneous polysaccharide (CSPW) was extracted and purified from coix seed. Furthermore, the saliva-gastrointestinal digestion and fecal fermentation behavior of CSPW were simulated in vitro. The results showed that CSPW was mainly composed of glucose. It cannot be degraded by the simulated salivary and intestinal digestive system, but can be degraded by the simulated gastric digestive system. After fermentation for 24 h, CSPW promoted the production of short-chain fatty acids (SCFAs), with acetic acid, propionic acid and n-butyric acid being the main metabolites. In addition, CSPW could significantly regulate the composition and microbial diversity of gut microbiota by increasing the relative abundance of beneficial bacteria, such as Limosilicactobacillus, Bifidobacterium and Collinsella. Finally, further analysis of functional prediction revealed that amino acid metabolism, nucleotide metabolism and carbohydrate metabolism were the most important pathways for CSPW to promote health. In summary, our findings suggested that CSPW could potentially be used as a good source of prebiotics because it can be used by gut microbiota to produce SCFAs and regulate the gut microbiota.

Removal of methylene blue by porous biochar obtained by KOH activation from bamboo biochar.

A series of activated biochar (KBBC-700, KBBC-800 and KBBC-900) which were modified by KOH and pyrolysis at various temperatures from ball-milling bamboo powder were obtained. The physicochemical properties and pore structures of activated biochar were investigated by scanning electron microscopy (SEM), fourier transform infrared spectoscopy (FT-IR), X-ray diffraction (XRD) and N2 adsorption/desorption. The adsorption performance for the removal of methylene blue (MB) was deeply studied. The results showed that KBBC-900 obtained at activation temperature of 900 °C exhibited a great surface area which reached 562 m2/g with 0.460 cm3/g of total pore volume. The enhancement of adsorption capacity could be ascribed to the increase of surface oxygen-containing functional groups, aromatization and mesoporous channels. The adsorption capacity was up to 67.46 mg/g under the optimum adsorption parameters with 2 g/L of adsorbent dose, 11 of initial solution pH and 298 K of the reactive temperature. The adsorption capacity was 70.63% of the first time after the material was recycled for three cycles. The kinetics indicated that the adsorption equilibrium time for MB on KBBC-900 was of about 20 min with the data fitted better to the pseudo-second-order kinetics model. The adsorption process was mainly dominated by chemical adsorption. Meanwhile, the adsorption isotherm showed that the Langmuir model fitted the best, and thermodynamic parameters revealed that the adsorption reaction was the endothermic nature and the spontaneous process. Adsorption of MB mainly attributed to electrostatic interactions, cation-π electron interaction and redox reaction. This study suggested that the activated biochar obtained by KOH activation from bamboo biochar has great potentials in the practical application to remove MB from wastewater.

Fully Bio-Based Adhesive from Tannin and Sucrose for Plywood Manufacturing with High Performances.

Fully bio-based adhesives are beneficial to reduce the dependence of the wood adhesive industry on synthetic resins based on petrochemical resources and enhance the market competitiveness of adhesives. A fully bio-based wood adhesive composed of tannin and sucrose was developed and successfully used in the preparation of plywood. Effects of the preparation technology on the bonding strength and water resistance of plywood were investigated, and the properties of the adhesive were analyzed by Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TG) and X-ray diffraction (XRD) in this study. The results showed that: (1) Compared with other biomass adhesives, tannin-sucrose adhesive had the characteristics of high-solid content and low viscosity, which had the potential to prepare particleboard and fiberboard. (2) A proper mass ratio of tannin to sucrose was key to obtaining a tannin-sucrose adhesive with better properties. (3) The optimum preparation process of tannin-sucrose adhesive for plywood was as follows: hot-pressing temperature of 210 °C, hot-pressing time of 1.2 min/mm, m(tannin):m(sucrose) of 60:40 and adhesive loading of 160 g/m2. Under these conditions, the water-resistant bonding strength of the plywood was 0.89 MPa, which met the strength requirements of the Type II standard of plywood in GB/T 17657-2013. (4) The hot-pressing temperature played a decisive role in the tannin-sucrose adhesive, and the good performance of the plywood was maintained when the temperature was 210 °C or above. Thus, the prepared tannin-sucrose adhesive had high-bonding strength, good water resistance and thermal stability.

In vitro fecal fermentation characteristics of bamboo insoluble dietary fiber and its impacts on human gut microbiota.

Bamboo contains abundant hemicellulose, cellulose, and lignin, which are a high-quality insoluble dietary fiber (IDF) raw material. To investigate IDF- induced changes in the production of short-chain fatty acids (SCFAs) and the composition of human gut microbiota, IDF was extracted by alkaline hydrogen peroxide (named BIDF), complex enzymatic hydrolysis method (named OIDF) from bamboo, and commercial bamboo fiber BF90. The in vitro fecal fermentation characteristics of BIDF, OIDF, BF90 and its impacts on human gut microbiota were studied for the first time. Results showed that BIDF, OIDF, and BF90 could promote the production of total SCFAs after 24 h fermentation. Additionally, BIDF could alter the composition and microbial diversity of gut microbiota, especially increase the relative abundance of Bacteroides and decrease the ratio of Firmicutes to Bacteroidetes (F/B) value. These results revealed that the IDF from bamboo could be partially utilized by specific bacteria in human intestines and provide a reference for the study of the effects of IDF fermentation on SCFAs production and microbial composition.

A New Wood Adhesive Based on Recycling Camellia oleifera Cake-Protein: Preparation and Properties.

In order to improve the initial viscosity and stability of Camellia oleifera cake-protein adhesive, Camellia oleifera cake-protein was blended with defatted soybean protein (DSP), soybean protein isolate (SPI), and casein, followed by adhesive preparation through degradation and crosslinking methods. The performance of Camellia oleifera cake-protein adhesive was investigated by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopic (SEM), and thermogravimetric (TG) and X-ray diffraction (XRD). The results showed that DSP, SPI, and casein likely promoted the effective degradation of Camellia oleifera cake-protein, and, thus, more active groups were formed in the system, accompanied by more reactivity sites. The prepared adhesive had a lower curing temperature, and higher initial viscosity and stability, but the storage time was shortened. Moreover, DSP, SPI, and casein, themselves, were degraded into peptide chains with lower molecular weights; thus, improving the overall flexibility of the adhesive, facilitating a better elastic contact and regular array between crosslinking products, and further strengthening the crosslinked structure and density of the products. After curing, a compact and coherent reticular structure was formed in the adhesive layer, with both bonding strength and water resistance being significantly improved. According to the results obtained, the next step will be to study the DSP-modified Camellia oleifera cake-protein adhesive in depth.

Changes in intracranial pressure gradients between the cerebral hemispheres in patients with intracerebral hematomas in one cerebral hemisphere.

BACKGROUND: Intracranial-pressure (ICP) monitoring is useful for patients with increased ICP following hemorrhagic stroke. In this study, the changes in pressure gradients between the two cerebral hemispheres were investigated after hemorrhagic stroke of one side, and after a craniotomy. METHODS: Twenty-four patients with acute cerebral hemorrhages and intracerebral hematomas who exhibited mass effect and midline shift to the contralateral side on computed tomography were selected for this study. After admission, both sides of the cranium were drilled, and optical fiber sensors were implanted to monitor the brain parenchyma pressure (BPP) in both cerebral hemispheres. All patients underwent surgical hematoma evacuations. The preoperative and postoperative BPP data from both cerebral hemispheres were collected at various time points and compared pairwise. RESULTS: There were statistically significant differences (P < 0.01) in the preoperative BPP values between the two hemispheres at three different time points. Differences in the BPP values between the two hemispheres at the time of surgery, and 24 and 48 h after surgery, were not statistically significant (P > 0.05). The posteroperative BPPs of both hemispheres were statistically significantly lower than preoperative recordings. CONCLUSIONS: BPP sensors should be applied to the injured cerebral hemisphere, because this becomes the source of increased ICP. Hematoma evacuation surgery effectively decreases ICP and eliminates pressure gradients between the two cerebral hemispheres, consequently enabling brain shift correction.