Amino acid regulated citrus pectin-based emulsion stability mediated by pH.

BACKGROUND: Citrus residuals are rich in nutrients like pectin, essential oil, and amino acids, which are wasted in the food industry. Moreover, citrus components often coexist with amino acids during emulsion preparation and application. RESULTS: Adding glutamic or arginine after emulsification resulted in a stable emulsion compared with adding them before emulsification. Adding glycine before or after emulsification had no effect on the emulsion stability. Emulsion stability was improved by adding glutamic acid at pH 6. Ionic interaction and hydrogen bonding were the main forms of bonding. The rhamnogalacturonan II domain was the potential binding site for the amino acids. CONCLUSIONS: The emulsions prepared by adding acidic amino acids or basic amino acids after emulsification were stable relative to those in which the amino acids were added before emulsification. However, the order in which neutral amino acids were added did not affect the emulsion stability after storage for 7 days. With an increase in the pH level, droplet size increased and emulsion stability decreased. All the results could be attributed to changes in the structure and properties of citrus pectin, as well as the interaction between citrus pectin and amino acids. This study may expand the application of citrus-derived emulsions in the food industry. © 2023 Society of Chemical Industry.

[Genome-wide identification of BvHAK gene family in sugar beet (Beta vulgaris) and their expression analysis under salt treatments].

High-affinity K+ transporter (HAK) is one of the most important K+ transporter families in plants and plays an important role in plant K+ uptake and transport. To explore the biological functions and gene expression patterns of the HAK gene family members in sugar beet (Beta vulgaris), physicochemical properties, the gene structure, chromosomal location, phylogenetic evolution, conserved motifs, three-dimensional structure, interaction network, cis-acting elements of promoter of BvHAKs were predicted by bioinformatic analysis, and their expression levels in different tissues of sugar beet under salt stress were analyzed by qRT-PCR. A total of 10 BvHAK genes were identified in the sugar beet genome. They contained 8-10 exons and 7-9 introns. The average number of amino acids was 778.30, the average molecular weight was 88.31 kDa, and the isoelectric point was 5.38-9.41. The BvHAK proteins contained 11-14 transmembrane regions. BvHAK4, -5, -7 and -13 were localized on plasma membrane, while others were localized on tonoplast. Phylogenetic analysis showed that HAK in higher plants can be divided into five clusters, namely cluster Ⅰ, Ⅱ, Ⅲ, Ⅳ, and Ⅴ, among which the members of cluster Ⅱ can be divided into three subclusters, including Ⅱa, Ⅱb, and Ⅱc. The BvHAK gene family members were distributed in cluster Ⅰ-Ⅳ with 1, 6, 1, and 2 members, respectively. The promoter of BvHAK gene family mainly contained stress responsive elements, hormone responsive elements, and growth and development responsive elements. The expression pattern of the BvHAK genes were further analyzed in different tissues of sugar beet upon salt treatment, and found that 50 and 100 mmol/L NaCl significantly induced the expression of the BvHAK genes in both shoots and roots. High salt (150 mmol/L) treatment clearly down-regulated their expression levels in shoots, but not in roots. These results suggested that the BvHAK gene family plays important roles in the response of sugar beet to salt stress.

Exploring the decentralized treatment of sulfamethoxazole-contained poultry wastewater through vertical-flow multi-soil-layering systems in rural communities.

Sulfamethoxazole (SMX) is the most widely distributed sulfonamide antibiotics detected in decentralized poultry wastewater in rural communities. As an economically-feasible and eco-friendly technology for decentralized wastewater treatment in rural areas, vertical-flow multi-soil-layering (MSL) system was promising to mitigate the ecological and human health risks from SMX in such areas. The treatment of SMX-contained poultry wastewater by using MSL systems was investigated for the first time, and the main and interactive effects of related multiple variables on system performance were explored through factorial analysis, including material of permeable layer, concentration of SMX, and pH of influent. Results indicated that SMX concentration and pH of influent showed significantly negative effects on SMX removal. Medical stone used in MSL systems with larger surface area could intensify the SMX removal compared to anthracite. MSL systems showed stable performances on SMX removal with the best SMX removal efficiency more than 91%. A novel stepwise-cluster inference (SCI) model was developed for the first time to map the multivariate numeric relationships between state variables and SMX removal under discrete and nonlinear complexities. It was demonstrated that the effect of SMX in wastewater with high concentration was significant on the differentiation of soil bacteria composition in MSL systems based on microbial diversity analysis. These results can help better understand the mechanism of SMX removal in MSL systems from perspectives of factorial analysis, numeric modeling, and microbiological change.

Multifunctional HNT@Fe3O4@PPy@DOX Nanoplatform for Effective Chemo-Photothermal Combination Therapy of Breast Cancer with MR Imaging.

Multifunctional nanoparticles for imaging and treatment in cancer are getting more and more attention recently. Herein, halloysite nanotubes (HNTs), natural clay nanotubes, are designed as multifunctional nanoplatform for targeted delivering photothermal therapy agents and chemotherapeutic drugs. Fe3O4 was anchored on the outer surfaces of HNTs and then doxorubicin (DOX) was loaded on the nanotubes. Afterward, a layer of polypyrrole (PPy), as photothermal agent, was wrapped on the tubes. The nanoplatform of HNT@Fe3O4@PPy@DOX can be guided to tumor tissue by an external magnetic field, and then performs chemo-photothermal combined therapy by 808 nm laser irradiation. HNT@Fe3O4@PPy@DOX shows the ability of T2-weighted magnetic resonance imaging, which could be considered as a promising application in magnetic targeting tumor therapy. In vitro and in vivo experiments demonstrate that HNTs nanoplatform has good biocompatibility and produces a strong antitumor effect trigged by near-infrared laser irradiation. The novel chemo-photothermal therapy nanoplatform based on HNTs may be developed as a multifunctional nanoparticle for imaging and therapy in breast cancer.

Sugar release and growth of biofuel crops are improved by downregulation of pectin biosynthesis.

Cell walls in crops and trees have been engineered for production of biofuels and commodity chemicals, but engineered varieties often fail multi-year field trials and are not commercialized. We engineered reduced expression of a pectin biosynthesis gene (Galacturonosyltransferase 4, GAUT4) in switchgrass and poplar, and find that this improves biomass yields and sugar release from biomass processing. Both traits were maintained in a 3-year field trial of GAUT4-knockdown switchgrass, with up to sevenfold increased saccharification and ethanol production and sixfold increased biomass yield compared with control plants. We show that GAUT4 is an α-1,4-galacturonosyltransferase that synthesizes homogalacturonan (HG). Downregulation of GAUT4 reduces HG and rhamnogalacturonan II (RGII), reduces wall calcium and boron, and increases extractability of cell wall sugars. Decreased recalcitrance in biomass processing and increased growth are likely due to reduced HG and RGII cross-linking in the cell wall.

Neuroprotective effects of Ginkgo biloba extract and Ginkgolide B against oxygen-glucose deprivation/reoxygenation and glucose injury in a new in vitro multicellular network model.

Acute ischemic stroke (AIS), as the third leading cause of death worldwide, is characterized by its high incidence, mortality rate, high incurred disability rate, and frequent reoccurrence. The neuroprotective effects of Ginkgo biloba extract (GBE) against several cerebral diseases have been reported in previous studies, but the underlying mechanisms of action are still unclear. Using a novel in vitro rat cortical capillary endothelial cell-astrocyte-neuron network model, we investigated the neuroprotective effects of GBE and one of its important constituents, Ginkgolide B (GB), against oxygen-glucose deprivation/reoxygenation and glucose (OGD/R) injury. In this model, rat cortical capillary endothelial cells, astrocytes, and neurons were cocultured so that they could be synchronously observed in the same system. Pretreatment with GBE or GB increased the neuron cell viability, ameliorated cell injury, and inhibited the cell apoptotic rate through Bax and Bcl-2 expression regulation after OGD/R injury. Furthermore, GBE or GB pretreatment enhanced the transendothelial electrical resistance of capillary endothelial monolayers, reduced the endothelial permeability coefficients for sodium fluorescein (Na-F), and increased the expression levels of tight junction proteins, namely, ZO-1 and occludin, in endothelial cells. Results demonstrated the preventive effects of GBE on neuronal cell death and enhancement of the function of brain capillary endothelial monolayers after OGD/R injury in vitro; thus, GBE could be used as an effective neuroprotective agent for AIS/reperfusion, with GB as one of its significant constituents.

Network-Based Approach to Identify Potential Targets and Drugs that Promote Neuroprotection and Neurorepair in Acute Ischemic Stroke.

Acute ischemic stroke (AIS) accounts for more than 80% of the approximately 610,000 new stroke cases worldwide every year. Both ischemia and reperfusion can cause death, damage, and functional changes of affected nerve cells, and these alterations can result in high rates of disability and mortality. Therefore, therapies aimed at increasing neuroprotection and neurorepair would make significant contributions to AIS management. However, with regard to AIS therapies, there is currently a large gap between experimental achievements and practical clinical solutions (EC-GAP-AIS). Here, by integrating curated disease-gene associations and interactome network known to be related to AIS, we investigated the molecular network mechanisms of multi-module structures underlying AIS, which might be relevant to the time frame subtypes of AIS. In addition, the EC-GAP-AIS phenomenon was confirmed and elucidated by the shortest path lengths and the inconsistencies in the molecular functionalities and overlapping pathways between AIS-related genes and drug targets. Furthermore, we identified 23 potential targets (e.g. ADORA3, which is involved in the regulation of cellular reprogramming and the extracellular matrix) and 46 candidate drugs (e.g. felbamate, methylphenobarbital and memantine) that may have value for the treatment of AIS.

[Resource situation investigation and analysis about endangered Chinese herbal medicine Daphnes Cortex].

In order to figure out the status and distribution of the wild and cultivated resources of traditional Chinese medicine Daphnes Cortex, its suitable habitat and endangering factors were analyzed to provide the basis for its rational use, protection and cultivation.Our research group tooka resources survey in Shanxi, Gansu, Sichuan and Qinghai provinces, which include 23 counties. Investigation and sampling investigation combined with interview were carried out. The total reserve of resources was estimated through route-quadrat method in combination with the vegetation and soil-type map area method. The results indicated that there was no obvious change between the present distribution ranges of the wild Daphnes Cortex and its historical records, but the density of the population has undergone major changes. The wild reserves resources has declined seriously, even on the verge of exhaustion in some regions. According to the survey results, the current total reserve of the wild Daphnes Cortex in the four provinces was no more than 600 tons. Simultaneously, we only found the cultivated resource in a mountain at an altitude of about 2 800 m in Kang county of Gansu province, which cropping scope was about 33 000 m². The cultivated resource can't provide medicinal products at present, because their growing period is too short to have curative effect. Destructive excavation and the longer growth cycle result in a sharp decline of the wild resources reserves, even to the point of extinction. Artificial cultivation of product will become the main source of medicinal resources in the future. Therefore, we must protect its suitable habitat, formulate rational harvesting policy, strengthen the supervision of government departments, collect and establish the germplasm nursery and seed bank. On the basis, we must carry out studies into seed-selecting and breeding as well as rapid propagation and growth technology at once.