ABSTRACT
Polysaccharides derived from diverse sources exhibit distinct rheological and gel properties, exerting a profound impact on their applicability in the food industry. In this study, we collected five Gracilaria chouae samples from distinct geographical regions, namely Rizhao (RZ), Lianyungang (LYG), Ningde (ND), Beihai (BH), and a wild source from Beihai (BHW). We conducted analyses on the chemical composition, viscosity, and rheological properties, as well as gel properties, to investigate the influence of chemical composition on variations in gel properties. The results revealed that the total sugar, sulfate content, and monosaccharide composition of G. chouae polysaccharides exhibit similarity; however, their anhydrogalactose content varies within a range of 15.31% to 18.98%. The molecular weight distribution of G. chouae polysaccharides ranged from 1.85 to 2.09 × 103 kDa. The apparent viscosity of the LYG and BHW polysaccharides was relatively high, whereas that of RZ and ND was comparatively low. The gel strength displayed a similar trend. BHW and LYG exhibited solid-like behavior, while ND, RZ, and BH demonstrated liquid-like characteristics at low frequencies. The redundancy analysis (RDA) analysis revealed a positive correlation between the texture profile analysis (TPA) characteristics and anhydrogalactose. The study could provide recommendations for the diverse applications of G. chouae polysaccharides derived from different geographical regions.
ABSTRACT
Plasma technology as an advanced oxidation technology, has gained increasing interest to generate numerous chemically reactive species during the plasma discharge process. Such chemically reactive species can trigger a chain of chemical reactions leading to the degradation of macromolecules including polysaccharides. This review primarily summarizes the generation of various chemically reactive species during plasma treatment and their effects on the physico-chemical properties and biological activities of polysaccharides. During plasma treatment, the type of chemically reactive species that play a major role is related to equipment, working gases and types of polysaccharides. The primary chain structure of polysaccharides did not changed much during the plasma treatment, other physico-chemical properties might be changed, such as molecular weight, solubility, hydrophilicity, rheological properties, gel properties, crystallinity, elemental composition, glycosidic bonding, and surface morphology. Additionally, the biological activities of plasma-treated polysaccharides including antibacterial, antioxidant, immunological, antidiabetic activities, and seed germination promotion activities in agriculture could be improved. Therefore, plasma treatment has the potential application in preparing polysaccharides with enhanced biological activities.
Subject(s)
Plasma Gases , Polysaccharides , Polysaccharides/chemistry , Polysaccharides/pharmacology , Plasma Gases/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Molecular Weight , Solubility , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , HumansABSTRACT
Traditional fermented milks are produced through an inoculation process that involves the deliberate introduction of microorganisms that have been adapted and perpetuated across successive generations. However, the changes in the microbiota of traditional fermented milk during long-term inoculation fermentation in a laboratory environment remain unclear. In this study, we collected 5 samples of traditional fermented milk samples from 5 different counties in Tibet (3 kurut products) and Xinjiang (2 tarag products) of China, which served as starter cultures for a 9-mo continuous inoculation fermentation experiment. We analyzed the inter- and intra-population variations in the microbial communities of the collected samples, representing their macrodiversity and microdiversity, using shotgun metagenomic sequencing. Across all samples, we obtained a total of 186 high-quality metagenomic-assembled genomes, including 7 genera and 13 species with a relative abundance of more than 1%. The majority of these genomes were annotated as Lactobacillus helveticus (60.46%), Enterococcus durans (9.52%), and Limosilactobacillus fermentum (6.23%). We observed significant differences in species composition and abundance among the 5 initial inoculants. During the long-term inoculation fermentation, we found an overall increasing trend in species diversity, composition, and abundances of carbohydrate metabolism module-encoding genes in the fermented milk bacterial metagenome, while the fermented milk virome exhibited a relatively narrow range of variation. Lactobacillus helveticus, a dominant species in traditional fermented milk, displayed high stability during the long-term inoculation fermentation. Our study provides valuable insights for the industrial production of traditional fermented milk.
ABSTRACT
The applications of fucoidan in the food industry were limited due to its high molecular weight and low solubility. Moderate degradation was required to depolymerize fucoidan. A few studies have reported that fucoidan has potential antibacterial activity, but its antibacterial mechanism needs further investigation. In this study, the degraded fucoidans were obtained after ultraviolet/hydrogen peroxide treatment (UV/H2O2) at different times. Their physicochemical properties and antibacterial activities against Staphylococcus aureus and Escherichia coli were investigated. The results showed that the average molecular weights of degraded fucoidans were significantly decreased (up to 22.04 times). They were mainly composed of fucose, galactose, and some glucuronic acid. Fucoidan degraded for 90 min (DFuc-90) showed the strongest antibacterial activities against Staphylococcus aureus and Escherichia coli, with inhibition zones of 27.70 + 0.84 mm and 9.25 + 0.61 mm, respectively. The minimum inhibitory concentrations (MIC) were 8 mg/mL and 4 mg/mL, respectively. DFuc-90 could inhibit the bacteria by damaging the cell wall, accumulating intracellular reactive oxygen species, reducing adenosine triphosphate synthesis, and inhibiting bacterial metabolic activity. Therefore, UV/H2O2 treatment could effectively degrade fucoidan and enhance its antibacterial activity.
Subject(s)
Anti-Bacterial Agents , Escherichia coli , Hydrogen Peroxide , Microbial Sensitivity Tests , Polysaccharides , Staphylococcus aureus , Ultraviolet Rays , Polysaccharides/pharmacology , Polysaccharides/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Molecular Weight , Reactive Oxygen Species/metabolismABSTRACT
Gelatin and sodium alginate (SA) are two important biological macromolecules, exhibiting excellent biocompatibility and gel-forming ability. However, traditional SA and gelatin hydrogel displays limited mass transport, low porosity, instability, and poor mechanical properties extremely restricted their therapeutic effect and application scenarios. Herein, microbial fermentation and synergistic toughening strategies were used for preparing macroporous and tough hydrogel. The study investigated the fermentation and toughening conditions of hydrogel. The hydrogel composed of CaCl2 cross-linked physically network and EDC/NHS cross-linked covalently network, exhibiting significantly improved mechanical properties, and excellent recovery efficiency. In addition, the hydrogel has a hierarchical macroporous structure of 100-500 µm, demonstrating high porosity of 10 times, swelling rate of 1541.0 %, and high mass infiltration capability. Further, after Ag+ treatment, the macroporous hydrogel dressing showed outstanding biocompatibility. Compared with non-porous hydrogel, the resulting macroporous hydrogel dressing displayed high antibacterial and antioxidant properties. It could effectively alleviate intracellular ROS formation induced by H2O2.In vivo experiments indicated that it has significantly better effect than non-porous hydrogel in accelerating wound healing. The overall results suggest that the gelatin/SA-based macroporous and tough hydrogel proposed in this study holds excellent prospects for application in wound dressings.
Subject(s)
Alginates , Anti-Bacterial Agents , Fermentation , Gelatin , Hydrogels , Wound Healing , Alginates/chemistry , Alginates/pharmacology , Gelatin/chemistry , Hydrogels/chemistry , Hydrogels/pharmacology , Wound Healing/drug effects , Porosity , Animals , Mice , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bandages , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Antioxidants/pharmacology , Antioxidants/chemistryABSTRACT
Three Laminaria japonica polysaccharides (LJPs) extracted via water extraction (LJP-W), acid extraction (LJP-A), and enzymatic extraction (LJP-E) were used as raw materials to be cross-linked with chitosan and polyvinyl alcohol to prepare hydrogels. Compared with conventional hydrogel systems, all three types of LJP-based polysaccharide hydrogels exhibited better swelling properties (14 times their original weight) and the absorption ability of simulated body fluid (first 2 h: 6-10%). They also demonstrated better rigidity and mechanical strength. Young's modulus of LJP-E was 4 times that of the blank. In terms of hemostatic properties, all three polysaccharide hydrogels did not show significant cytotoxic and hemolytic properties. The enzyme- and acid-extracted hydrogels (LJP-Gel-A and LJP-Gel-E) demonstrated better whole-blood coagulant ability compared with the water-extracted hydrogel (LJP-Gel-W), as evidenced by the whole blood coagulation index being half that of LJP-Gel-W. Additionally, the lactate dehydrogenase viabilities of LJP-Gel-A and LJP-Gel-E were significantly higher, at about four and three times those of water extraction, respectively. The above results suggested that LJP-Gel-A and LJP-Gel-E exhibited better blood coagulation capabilities than LJP-Gel-W, due to their enhanced platelet enrichment and adhesion properties. Consequently, these hydrogels are more conducive to promoting coagulation and have good potential for wound hemostasis.
Subject(s)
Blood Coagulation , Edible Seaweeds , Hemostatics , Hydrogels , Laminaria , Polysaccharides , Hydrogels/chemistry , Hydrogels/pharmacology , Laminaria/chemistry , Polysaccharides/chemistry , Polysaccharides/pharmacology , Polysaccharides/isolation & purification , Blood Coagulation/drug effects , Hemostatics/pharmacology , Hemostatics/chemistry , Hemostatics/isolation & purification , Humans , Animals , Chitosan/chemistry , Chitosan/pharmacology , Polyvinyl Alcohol/chemistry , Hemostasis/drug effects , Hemolysis/drug effectsABSTRACT
This was the first study that examined the effects of oat ß-glucan and inulin on diet-induced nonalcoholic steatohepatitis (NASH) in circadian-disrupted (CD)-male C57BL/6J mice. CD intensified NASH, significantly increasing alanine aminotransferase and upregulating hepatic tumor necrosis factor α (TNFα) and transforming growth factor ß 1 (TGFß1). However, these observations were significantly alleviated by oat ß-glucan and inulin treatments. Compared to CD NASH mice, oat ß-glucan significantly decreased the liver index, aspartate aminotransferase (AST), and insulin. In prebiotic-treated and CD NASH mice, significant negative correlations were found between enrichment of Muribaculaceae bacterium Isolate-036 (Harlan), Muribaculaceae bacterium Isolate-001 (NCI), and Bacteroides ovatus after oat ß-glucan supplementation with TNFα and TGFß1 levels; and enrichment of Muribaculaceae bacterium Isolate-110 (HZI) after inulin supplementation with AST level. In conclusion, oat ß-glucan and inulin exhibited similar antiliver injury, anti-inflammatory, and antifibrotic activities but had no effect on cecal short-chain fatty acids and gut microbiota diversity in CD NASH mice.
Subject(s)
Non-alcoholic Fatty Liver Disease , beta-Glucans , Male , Mice , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , Inulin/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , Mice, Inbred C57BL , Liver/metabolismABSTRACT
This study aimed to estimate the Malaysian adult population's current dietary exposure and margin of exposure (MOE) to the carcinogenic processing contaminant, acrylamide. A total of 448 samples from 11 types of processed foods were collected randomly throughout Malaysia in the year 2015 and 2016. Acrylamide was analysed in samples using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) with a limit of detection (LOD) of 10 µg/kg and a limit of quantification (LOQ) of 25 µg/kg. The highest average level of acrylamide (772 ± 752 µg/kg) was found in potato crisps, followed by French fries (415 ± 914 µg/kg) and biscuits (245 ± 195 µg/kg). The total acrylamide exposure for the adult Malaysian was 0.229 and 1.77 µg/kg body weight per day for average and high consumers, respectively. The MOE were 741 and 1875 for the average consumer based on cancer and non-cancer effects of acrylamide, respectively. Meanwhile, for high consumers, the MOE is 96 for cancer and 243 for non-cancer effects. These findings indicate potential carcinogenic risks from acrylamide exposure among Malaysian adults, especially in Malay and other Bumiputra groups compared to Chinese, Indian, and other ethnic groups, while non-cancer effects appeared less concerning.
Subject(s)
Acrylamide , Dietary Exposure , Dietary Exposure/analysis , Chromatography, Liquid , Acrylamide/toxicity , Acrylamide/analysis , Tandem Mass Spectrometry , Food , Carcinogens/toxicity , Carcinogens/analysis , Food Contamination/analysisABSTRACT
Management and improving saline-alkali land is necessary for sustainable agricultural development. We conducted a field experiment to investigate the effects of spraying lactic acid bacteria (LAB) on the cucumber and tomato plant soils. Three treatments were designed, including spraying of water, viable or sterilized LAB preparations to the soils of cucumber and tomato plants every 20 days. Spraying sterilized or viable LAB could reduce the soil pH, with a more obvious effect by using viable LAB, particularly after multiple applications. Metagenomic sequencing revealed that the soil microbiota in LAB-treated groups had higher alpha-diversity and more nitrogen-fixing bacteria compared with the water-treated groups. Both viable and sterilized LAB, but not water application, increased the complexity of the soil microbiota interactive network. The LAB-treated subgroups were enriched in some KEGG pathways compared with water or sterilized LAB subgroups, such as environmental information processingrelated pathways in cucumber plant; and metabolism-related pathways in tomato plant, respectively. Redundancy analysis revealed association between some soil physico-chemical parameters (namely soil pH and total nitrogen) and bacterial biomarkers (namely Rhodocyclaceae, Pseudomonadaceae, Gemmatimonadaceae, and Nitrosomonadales). Our study demonstrated that LAB is a suitable strategy for decreasing soil pH and improving the microbial communities in saline-alkali land.(AU)
Subject(s)
Humans , Bacteria/genetics , Soil Microbiology , Plants , Alkalies , Lactobacillales , Metagenome , Microbiology , Microbiological Techniques , Soil , Biotechnology/methods , Metagenomics , Water/metabolismABSTRACT
Conductive hydrogels become increasing attractive for flexible electronic devices and biosensors. However, challenges still remain in fabrication of flexible hydrogels with high electrical conductivity, self-healing capability and adhesion property. Herein, a conductive hydrogel (PSDM) was prepared by solution-gel method using MXene and dopamine modified polypyrrole as conductive enhanced materials, polyvinyl alcohol and silk fibroin as gel networks, and borax as cross-linking agent. Notably, the PSDM hydrogels not only showed high permeability (13.82 mgâcm-2âh-1), excellent stretch ability (1235 %), high electrical conductivity (11.3 S/m) and long-term stability, but also exhibited high adhesion performance and self-healing properties. PSDM hydrogels displayed outstanding sensing performance and durability for monitoring human activities including writing, finger bending and wrist bending. The PSDM hydrogel was made into wearable flexible electrodes and realized accurate, sensitive and reliable detection of human electromyographic and electrocardiographic signals. The sensor was also applied in human-computer interaction by collecting electromyography signals of different gestures for machine learning and gesture recognition. According to 480 groups of data collected, the recognition accuracy of gestures by the electrodes was close to 100 %, indicating that the PSDM hydrogel electrodes possessed excellent sensing performance for high precision data acquisition and human-computer interaction interface.
Subject(s)
Fibroins , Nitrites , Prunella , Transition Elements , Wearable Electronic Devices , Humans , Polymers , Polyvinyl Alcohol , Pyrroles , Electric Conductivity , HydrogelsABSTRACT
Increasing hydrogen peroxide (H2O2)-based systems have been developed to degrade various polysaccharides due to the presence of highly reactive free radicals, but published degradation mechanisms are still limited. Therefore, this study aimed to clarify the degradation mechanism of six typical glucosidic bonds from different disaccharides in an ultraviolet (UV)/H2O2 system. The results showed that the H2O2 concentration, disaccharide concentration, and radiation intensity were important factors affecting pseudo-first-order kinetic constants. Hydroxyl radical, superoxide radical, and UV alone contributed 58.37, 18.52, and 19.17% to degradation, respectively. The apparent degradation rates ranked in the order of cellobiose ≈ lactose > trehalose ≈ isomaltose > turanose > sucrose ≈ maltose. The reaction pathways were then deduced after identifying their degradation products. According to quantum chemical calculations, the cleavage of α-glycosidic bonds was more kinetically unfavorable than that of ß-glycosidic bonds. Additionally, the order of apparent degradation rates depended on the energy barriers for the formation of disaccharide-based alkoxyl radicals. Moreover, energy barriers for homolytic scissions of glucosidic C1-O or C7-O sites of these alkoxyl radicals ranked in the sequence: α-(1 â 2) ≈ α-(1 â 3) < α-(1 â 4) < ß-(1 â 4) < α-(1 â 6) < α-(1 â 1) glucosidic bonds. This study helps to explain the mechanisms of carbohydrate degradation by free radicals.
Subject(s)
Alcohols , Hydrogen Peroxide , Water Pollutants, Chemical , Hydrogen Peroxide/chemistry , Glucosides , Disaccharides/chemistry , Maltose/metabolism , Sucrose/chemistry , Ultraviolet Rays , Oxidation-Reduction , Kinetics , Water Pollutants, Chemical/chemistryABSTRACT
Management and improving saline-alkali land is necessary for sustainable agricultural development. We conducted a field experiment to investigate the effects of spraying lactic acid bacteria (LAB) on the cucumber and tomato plant soils. Three treatments were designed, including spraying of water, viable or sterilized LAB preparations to the soils of cucumber and tomato plants every 20 days. Spraying sterilized or viable LAB could reduce the soil pH, with a more obvious effect by using viable LAB, particularly after multiple applications. Metagenomic sequencing revealed that the soil microbiota in LAB-treated groups had higher alpha-diversity and more nitrogen-fixing bacteria compared with the water-treated groups. Both viable and sterilized LAB, but not water application, increased the complexity of the soil microbiota interactive network. The LAB-treated subgroups were enriched in some KEGG pathways compared with water or sterilized LAB subgroups, such as environmental information processing-related pathways in cucumber plant; and metabolism-related pathways in tomato plant, respectively. Redundancy analysis revealed association between some soil physico-chemical parameters (namely soil pH and total nitrogen) and bacterial biomarkers (namely Rhodocyclaceae, Pseudomonadaceae, Gemmatimonadaceae, and Nitrosomonadales). Our study demonstrated that LAB is a suitable strategy for decreasing soil pH and improving the microbial communities in saline-alkali land.
Subject(s)
Lactobacillales , Solanum lycopersicum , Alkalies , Bacteria/genetics , Soil , Plants , Water , Soil MicrobiologyABSTRACT
The main purpose of this study was to analyze the structural properties and anti-inflammatory activity of the purified fractions derived from UV/H2O2-degraded polysaccharides from Sargassum fusiforme. Results indicated that twofractions with different monosaccharide compositions and morphological characteristics, PT-0.25 (yield 39.5%) and PT-0.5 (yield 23.9%), were obtained. The average molecular weights of PT-0.25 and PT-0.5 were 14.52 kDa and 22.89 kDa, respectively. In addition, PT-0.5 exhibited better anti-inflammatory activity with a clear dose dependence. The mechanism was associated with the inhibition of LPS-activated Toll-like receptor 4-mediated inflammatory pathways in RAW264.7 cells. The results showed that PT-0.5 was a complex polysaccharide mainly composed of 4-Fucp, t-Manp, 6-Galp, t-Fucp, and 3,4-GlcAp. These results would provide theoretical support for studying the structural properties and biological activities of UV/H2O2-degraded polysaccharides.
Subject(s)
Hydrogen Peroxide , Sargassum , Hydrogen Peroxide/pharmacology , Hydrogen Peroxide/metabolism , Sargassum/chemistry , Polysaccharides/chemistry , Anti-Inflammatory AgentsABSTRACT
Lacticaseibacillus rhamnosus (L. rhamnosus) is widely recognized as a probiotic species, and it exists in a variety of environments including host gut and dairy products. This work aimed at conducting a large-scale comparative genomics analysis of 384 L. rhamnosus genomes (257 whole-sequence or metagenomic-assembled genomes from gut-associated isolates [122 and 135 retrieved from the UHGG and NCBI databases, respectively] and 127 genomes from dairy isolates [34 from the NCBI database; 93 isolated from a cheese sample and sequenced here]). Our results showed that L. rhamnosus had a large and open pan-genome (15,253 pan-genes identified from all 384 genomes; 15,028 pan-genes if the 93 cheese-originated isolates were excluded). The core-gene phylogenetic tree constructed from the 384 L. rhamnosus genomes comprised five phylogenetic branches, with a random distribution of dairy and gut-associated isolates/genomes across the tree. No significant difference was identified in the overall profile of metabolism-related genes between dairy and gut-associated genomes; however, notably, the gut-associated strains/isolates contained more genes coding for specific metabolic pathways and carbohydrate-active enzymes, e.g., lacto-N-biosidase (EC 3.2.1.140; GT20) and lacto-N-biose phosphorylase/galacto-N-biose phosphorylase (EC 2.4.1.211; GH112). Further, we found that there was obvious intra-species diversification of the 93 cheese-originated L. rhamnosus isolates, forming three clades (Clades A, B, and C) in the reconstructed core-gene phylogenetic tree. There were numerous single nucleotide variations (over 10,000) across the three clades. Moreover, significant differences were observed in the content of metabolism-related genes across clades (p < 0.05, Adonis test), characterized by the enrichment in glycoside hydrolases in Clade C and the possession of unique metabolic pathways in each clade. These results implicated genomics/functional diversification of L. rhamnosus in a single food matrix and niche-driven adaptive evolution of isolates from dairy and host gut-associated origins. Our study shed insights into the selection of candidate strains for food industry applications.
Subject(s)
Lacticaseibacillus rhamnosus , Lacticaseibacillus rhamnosus/genetics , Genome, Bacterial/genetics , Lacticaseibacillus , Phylogeny , Genomics/methods , Phosphorylases/geneticsABSTRACT
Traditional fermented milks are produced by inoculating technique, which selects well-adapted microorganisms that have been passed on through generations. Few reports have used naturally fermented milks as model ecosystems to investigate the mechanism of formation of intra-species microbial diversity. Here, we isolated and whole-genome-sequenced a total of 717 lactic acid bacterial isolates obtained from 12 independent naturally fermented milks collect from 12 regions across five countries. We further analyzed the within-sample intra-species phylogenies of 214 Lactobacillus helveticus isolates, 97 Lactococcus lactis subsp. lactis isolates, and 325 Lactobacillus delbrueckii subsp. bulgaricus isolates. We observed a high degree of intra-species genomic and functional gene diversity within-/between-sample(s). Single nucleotide polymorphism-based phylogenetic reconstruction revealed great within-sample intra-species heterogeneity, evolving from multiple lineages. Further phylogenetic reconstruction (presence-absence gene profile) revealed within-sample inter-clade functional diversity (based on carbohydrate-active enzyme- and peptidase-encoding genes) in all three investigated species/subspecies. By identifying and mapping clade-specific genes of intra-sample clades of the three species/subspecies to the respective fermented milk metagenome, we found extensive potential inter-/intra-species horizontal gene transfer events. Finally, the microbial composition of the samples is closely linked to the nucleotide diversity of the respective species/subspecies. Overall, our results contribute to the conservation of lactic acid bacteria resources, providing ecological insights into the microbial ecosystem of naturally fermented dairy products.
Subject(s)
Lactobacillales , Lactobacillus delbrueckii , Lactococcus lactis , Animals , Milk/microbiology , Lactobacillales/genetics , Lactobacillus/genetics , Ecosystem , Phylogeny , Lactobacillus delbrueckii/geneticsABSTRACT
Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease nowadays. Currently, there is no officially approved drug to treat NAFLD. In view of the increasing global prevalence of NAFLD and an absence of treatments, the development of effective treatments is of utmost importance. ß-glucan, a natural bioactive polysaccharide, has demonstrated hepatoprotective effects in NAFLD prevention and treatment. This review solely focuses on gathering the published preclinical animal studies that demonstrated the anti-liver injury, anti-steatotic, anti-inflammatory, anti-fibrotic, and antioxidant activities of ß-glucan. The impact of ß-glucan on gut microbiota and its metabolites including short-chain fatty acids and bile acids as the underlying mechanism for its bioactive beneficial effect on NAFLD is also explored. Given the limited knowledge of ß-glucan on anti-fibrotic activity, bile acid metabolism, and gut microbiota function, additional relevant research is highly encouraged to lay a solid foundation for the use of food-derived ß-glucan as a functional food for NAFLD. It is envisaged that further investigation of food-derived ß-glucan in human clinical studies should be carried out for its wider utilization.
ABSTRACT
The high molecular weight and poor solubility of seaweed polysaccharides have limited their function and application. In this study, ultraviolet/hydrogen peroxide (UV/H2O2) treatment was used to prepare low-molecular-weight seaweed polysaccharides from Sargassum fusiforme. The effects of UV/H2O2 treatment on the physicochemical properties and anti-photoaging activity of S. fusiforme polysaccharides were studied. UV/H2O2 treatment effectively degraded polysaccharides from S. fusiforme (DSFPs), reducing their molecular weight from 271 kDa to 26 kDa after 2 h treatment. The treatment did not affect the functional groups in DSFPs but changed their molar percentage of monosaccharide composition and morphology. The effects of the treatment on the anti-photoaging function of S. fusiforme polysaccharides were investigated using human epidermal HaCaT cells in vitro. DFSPs significantly improved the cell viability and hydroxyproline secretion of UVB-irradiated HaCaT cells. In particular, DSFP-45 obtained from UV/H2O2 treatment for 45 min showed the best anti-photoaging effect. Moreover, DSFP-45 significantly increased the content and expression of collagen I and decreased those of pro-inflammatory cytokines, including interleukin-1ß, interleukin-6, and tumor necrosis factor-α. Thus, UV/H2O2 treatment could effectively improve the anti-photoaging activity of S. fusiforme polysaccharides. These results provide some insights for developing novel and efficient anti-photoaging drugs or functional foods from seaweed polysaccharides.
Subject(s)
Hydrogen Peroxide , Skin Neoplasms , Humans , Hydrogen Peroxide/pharmacology , Cell Survival , Collagen Type I , CytokinesABSTRACT
UV/H2O2 process is increasingly used to degrade carbohydrates, though the underlying mechanisms remain unclear. This study aimed to fill this knowledge gap, focusing on mechanisms and energy consumption involved in hydroxyl radical (â¢OH)-mediated degradation of xylooligosaccharides (XOSs) in UV/H2O2 system. Results showed that UV photolysis of H2O2 generated large amounts of â¢OH radicals, and degradation kinetics of XOSs fitted with a pseudo-first-order model. Xylobiose (X2) and xylotriose (X3), main oligomers in XOSs, were attacked easier by â¢OH radicals. Their hydroxyl groups were largely converted to carbonyl groups and then carboxy groups. The cleavage rate of glucosidic bonds was slightly higher than that of pyranose ring, and exo-site glucosidic bonds were more easily cleaved than endo-site bonds. The terminal hydroxyl groups of xylitol were more efficiently oxidized than other hydroxyl groups of it, causing an initial accumulation of xylose. Oxidation products from xylitol and xylose included ketoses, aldoses, hydroxy acids and aldonic acids, indicating the complexity of â¢OH radical-induced XOSs degradation. Quantum chemistry calculations revealed 18 energetically viable reaction mechanisms, with the conversion of hydroxy-alkoxyl radicals to hydroxy acids being the most energetically favorable (energy barriers <0.90 kcal/mol). This study will provide more understanding of â¢OH radicals-mediated degradation of carbohydrates.
Subject(s)
Water Pollutants, Chemical , Water Purification , Hydrogen Peroxide/chemistry , Xylose , Xylitol , Water Pollutants, Chemical/chemistry , Ultraviolet Rays , Kinetics , Oxidation-Reduction , Hydroxyl Radical/chemistry , Hydroxy Acids , Water Purification/methodsABSTRACT
Au coated magnetic polyphosphazene (MPCTP) composite particles (MPCTP@Au) were fabricated with sensitive SERS activity. The MPCTP particles were generated by coating polyphosphazene on Fe3O4 nanoparticles through precipitation polycondensation of hexachlorocyclotriphosphazene and phloroglucinol. MPCTP@Au composite particles were obtained by deposition of Au nanoparticles on MPCTP by the reduction of HAuCl4. The size and the thickness of the Au shell can be controlled by varying the amount of HAuCl4. The magnetic core endowed the composite particles with good magnetic responsiveness, which allowed the analyte to be enriched and separated from the complex matrix, and significantly simplifying the sample pretreatment procedure. The SERS activity of MPCTP@Au composite particles were evaluated by DTNB as model Raman reporter, and the limits of detection (LOD) of DTNB was 10-8 mol/L. A high efficient SERS immunoassay system based on the MPCTP@Au substrates for the detection of immunoproteins was developed. Human IgG and rabbit IgG were quantitatively determinated simultaneously by this immunoassay system. The quantitative determination of the immunoglobulin G (IgG) was achieved and the LOD of human IgG, rabbit IgG and the mixture of human IgG and rabbit IgG were as low as 10 fg/mL, 100 pg/mL and 1 ng/mL, respectively. The results showed that the MPCTP@Au composite particles have broad application prospects as high performance SERS active substrates for immunoprotein analysis.
Subject(s)
Metal Nanoparticles , Spectrum Analysis, Raman , Animals , Humans , Rabbits , Spectrum Analysis, Raman/methods , Gold/chemistry , Dithionitrobenzoic Acid , Metal Nanoparticles/chemistry , Immunoproteins , Immunoglobulin G , Magnetic PhenomenaABSTRACT
Arbutin, salidroside, polydatin, and phlorizin are typically natural bioactive phenolic glycosides. To improve the liposolubility and bioavailability, highly liposoluble derivatives including 6'-O-lauryl arbutin, 6'-O-lauryl salidroside, 6â³-O-lauryl polydatin, and 6â³-O-lauryl phlorizin were efficiently synthesized by enzymatic acylation in a green solvent 2-MeTHF. Their reaction conversions reached 84.4, 99.5, 99.8, and 89.1%, respectively, when catalyzed by Lipozyme 435 at 20 mg/mL at 50 °C. As expected, the derivatives had high logâ¯P (1.66-2.37) and retained good antioxidant activity, making them potential alternatives to butylated hydroxytoluene (BHT) and tert-butyl-hydroquinone (TBHQ) in lipid systems. Then, the intestinal permeability characteristics and metabolism of phenolic glycosides and their derivatives were investigated based on Caco-2 monolayers. The permeability of polydatin and phlorizin was mainly through active transport, but that of arbutin and salidroside involved both passive diffusion and active uptake. The acylated derivatives suffered from severe CES-mediated hydrolysis but exhibited a larger transported amount than phenolic glycosides.