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Vancomycin (Van) remains one of the first-line drugs for the treatment of wound infections caused by methicillin-resistant Staphylococcus aureus (MRSA). However, the unsatisfactory bioavailability of vancomycin alone has greatly limited its potential health benefits. Here a responsive chitosan-based hydrogel was developed as the delivery system which not only would reduce this side effect but also increase efficacy of vancomycin. The hydrogel was prepared by grafting chitosan and cinnamaldehyde-based thioacetal (CTA) together with ginipin (G) as the crosslinker. Upon exposure to reactive oxygen species which were enriched in the bacterial wound, the hydrogel can locally degrade and sustainably release the loaded vancomycin near the lesion to compete with the troubling MRSA. Compared with vancomycin alone, the chitosan-based hydrogel loaded with vancomycin demonstrated accelerated acute wound healing. This achievement reveals that this multi-functional hydrogel may be a promising drug-delivery device for improving the efficacy of local antibiotic therapy.

In recent years, graphitic carbon nitride (g-C3N4) has been developed greatly in the domain of water treatment. We adopted one-step calcination to enhance the light absorption of g-C3N4 with melamine-sponge (MS). A novel form of photocatalysts (gCNMx, x = 0.1, 0.2 and 0.3) were successfully prepared. The color of gCNMx changed with addition of MS. Experimental analysis demonstrated that C-doping and N vacancies increased the capacity of light absorption of gCNM0.2, and further increased efficiency of photothermal conversion and photogenerated holes. The sterilization efficiency of gCNM0.2 could rival a variety of metal photocatalysts. Moreover, the preparation of gCNM0.2 was cost-effective and environmental-friendly. Interestingly, the inactivation efficacy of gCNM0.2 for S. aureus depended heavily on the photogenerated holes, however, the decisive force toward S. typhimurium was photothermal conversion.

Probiotics are generally used as therapeutic intervention in inflammatory bowel disease. However, the low survival rate in harsh gastrointestinal environment and limited retention in intestine greatly restrict their health benefits. To address this problem, a ROS-responsive hydrogel based on hyaluronic acid (HA) was developed for encapsulation and targeted delivery of probiotics. The hydrogel was prepared facilely by physiological crosslink with methacrylated HA and thiolated thioketal. As a model probiotic, Lactobacillu reuteri showed a significantly increased survival rate in simulated digestive conditions after encapsulated in hydrogel. The negative properties conferred the hydrogel preferential adhesions to inflammation sites. Meanwhile, the excess reactive oxygen species (ROS) produced by inflamed colon tissues selectively cleaved thioketal linkages resulted in hydrogel degradation and local probiotics release. Furthermore, the hydrogel exerted an appropriate ROS-scavenge capacity and protected HT-29 cells from oxidative damage. Animal experiments indicated that hydrogel-encapsulated L. reuteri could remarkably alleviate the symptoms and improve the survival rate of mice with dextran sulfate sodium (DSS)-induced colitis. These results suggested that the biocompatible hydrogel may be a delivery platform to target inflamed intestines and expand the application of probiotics as pharmaceuticals.

Biofilms and intracellular bacteria often cause a series of overwhelming public health issues due to their strong drug resistance. Hence, chitosan nanoparticles (CS NPs), phosphatidylcholine and gentamicin were used to synthesize a novel nanodrug delivery system (GPC NPs). Dynamic light scattering (DLS) demonstrated that the surface zeta-potential of GPC NPs was −19.5 mV. The morphology of GPC NPs was observed by scanning electron microscopy (SEM). The gentamicin adsorption and release behaviors of GPC NPs were also investigated. The GPC NPs could effectively damage and remove the biofilm formed by pathogens through permeation of the antibiotic into the biofilm. In addition, the nanoparticles were readily engulfed by macrophages which facilitated the killing of intracellular bacteria and had neglectable cytotoxicity. Our study indicated that GPC NPs could be used as a promising nanoantibacterial agent against biofilms and intracellular bacteria.

Probiotics were found to be effective in ameliorating the microbial dysbiosis and inflammation caused by intestinal pathogens. However, biological challenges encountered during oral delivery have greatly limited their potential health benefits. Here, a model probiotic (Lactobacillus rhamnosus) was encapsulated in an intestinal-targeted hydrogel to alleviate bacterial enteritis in a novel mode. The hydrogel was prepared simply by the self-cross-linking of thiolated hyaluronic acid. Upon exposure to H2S which were excreted by surrounding intestinal pathogens, the hydrogel can locally degrade and rapidly release cargos to compete with source pathogens in turn for binding to the host. The mechanical properties of hydrogel were studied by rheological analysis, and the ideal stability was achieved at a polymer concentration of 4% (w/v). The morphology of the optimal encapsulation system was further measured by a scanning electron microscope, exhibiting uniform payload of probiotics. Endurance experiments indicated that the encapsulation of L. rhamnosus significantly enhanced their viability under gastrointestinal tract insults. Compared with free cells, encapsulated L. rhamnosus exerted better therapeutic effect against Salmonella-induced enteritis with negligible toxicity in vivo. These results demonstrate that this redox-responsive hydrogel may be a promising encapsulation and delivery system for improving the efficacy of orally administered probiotics.

Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, immunomodulatory, cancer, and other diseases. In this paper, a novel acidic polysaccharide RPAPS purified from Radix Paeoniae Alba was evaluated for its structural features and potential of immunomodulatory and antioxidant activities. RPAPS (molecular weight: 1.0× 105 Da) was mainly composed of α-(1 → 4)-Glcp, α-Arap, α-Galp, α-Rhap, β-D-Glcp, α-(1 → 6)-linked Glcp and GalA. Immunological tests indicated that RPAPS could improve RAW264.7 phagocytic activity and LPS-induced splenocyte proliferation. For antioxidant activities, RPAPS showed reducing power and DPPH scavenging activity in dose dependent. Moreover, RPAPS could significantly protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPS had the potential to be novel natural antioxidative and immunopotentiating agents for using in functional foods or medicine.

Objective. To analyze the in vitro antibacterial and antibiofilm activities of lysozyme (LYS) and its combination with various drugs against Gram-positive bacteria (GPB, n = 9 ), thus to provide an exploration direction for drug development. Methods. The minimum inhibitory concentrations (MICs) of linezolid (LZD), amikacin (AMK), ceftriaxone/sulbactam (CRO/SBT), cefotaxime/sulbactam (CTX/SBT), piperacillin/sulbactam (PIP/SBT), doxycycline (DOX), levofloxacin (LVX), amoxicillin/clavulanate potassium (7 : 1, AK71), imipenem (IPM), azithromycin (AZM), and their combinations with LYS were determined with tuber twice dilution. The antimicrobial and antibiofilm activities of LYS, AZM, LVX, and their combinations with others were evaluated through MTT and crystal violet assay. Results. High-dose LYS (30 μg/mL) combined with PIP/SBT and AK71, respectively, showed synergistic antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA), while it showed no synergistic activities when combined with other drugs. LYS and AZM inhibited the biofilm formation of one MRSA strain, but they and LVX had no similar activities against methicillin-resistant Staphylococcus epidermidis (MRSE) or vancomycin-resistant Enterococcus faecium (VREF). Particularly, LYS increased the permeability of biofilms of MRSA 33 and exhibited antibiofilm activities against MRSA 31 ( inhibition rate = 38.1 % ) and MRSE 61 ( inhibition rate = 46.6 % ). The combinations of PIP/SBT+LYS, AMK+LYS, and LZD+LYS showed stronger antibiofilm activities against MRSA 62, MRSE 62, MRSE 63, and VREF 11. Conclusion. The antimicrobial and antibiofilm activities of LYS against MRSA were better than AZM, while that of LYS against MRSE and VREF, respectively, was similar with AZM and LVX.

Bacterial infections are a growing global challenge for public health as antibiotic resistance could cause the failure of anti-infective treatment eventually. So, it is urgent to develop new potential antibacterial materials. Herein, a multifunctional chitosan (CS) functionalized magnetic Chlorin e6 (CS-MP-Ce6) was constructed to combat methicillin-resistant Staphylococcus aureus (MRSA) infection by integrating bacterial conjugation and enrichment, and near-infrared (NIR)-triggered photodynamic sterilization. CS-MP-Ce6 could efficiently capture bacteria due to positively charged property of CS, and Ce6 acted as an effective photodynamic killer to convert NIR light into local energy to enhance antibacterial activity. Specifically, after being trapped together with MRSA, CS-MP-Ce6 showed an excellent in vitro photodynamic sterilization ability. In vivo MRSA-induced abscess treatment studies showed faster healing when CS-MP-Ce6 was used as subcutaneous nano-localized energy sources with the assistance of external magnet to concentrate CS-MP-Ce6-bacteria conjugate. This work provides a promising framework for constructing a new system for efficiently combating MRSA.

The photosynthetic bacterium, Rhodopseudomonas palustris has been widely used as probiotics in aquaculture, while the molecular basis underlying the probiotic properties of this organism remains largely unknown. In this study, a novel extracellular polysaccharides (RPEPS-30) extracted from the fermentation of Rhodopseudomonas palustris was characterized. Results illustrated that RPEPS-30 was an α-mannan with a molecular weight of 46.82 kDa, which possessed a backbone consisted of 1, 2-linked and 1, 4-linked mannose residues, with side chains composed of 1 → 6 linked and 1 → 2,6 linked mannose residues and substitution at O-6. The in vitro immunomodulatory tests revealed that RPEPS-30 could enhance phagocytic capacity, NO release and mRNA expression of cytokines in macrophages. In addition, RPEPS-30 was shown to promote the growth of resident beneficial gut microbiotasuch as Lactobacillus reuteri, Bacteroides thetaiotaomicron and Akkermansia muciniphila. These findings might help us to partially understand the molecular mechanism concerning the probiotic properties of Rhodopseudomonas palustris, in which the extracellular polysaccharide RPEPS-30 stimulated host immune response and favored the growth of specific benificial micriobiota in the gut.

Many pathogenic bacteria can invade phagocytic and non-phagocytic cells and colonize inside, which protects them from the attack by host immune system and antibiotics. A novel amphiphilic molecule was synthesized through conjugation of streptomycin and decylamine to hyaluronan. Rapamycin was encapsulted by the spontaneous self-assembly of hyaluronan-based amphiphilic molecules. The newly formed micelles not only facilitated the entry of drugs into host cells in part via CD44 phagocytic receptor, released streptomycin in the acidic compartment, but also could activate autophagy. The micelles elicited an efficient killing capacity against intracellular bacteria through the promotion of streptomycin uptake and rapamycin-initiated activation of autophagy. This strategy might highlight an acid-sensitive hyaluronan-based drug delivery system for effective treatment of intracellular infections.

Bacterial biofilms are widely associated with persistent infections and food contamination. High resistance to conventional antimicrobial agents resulted in an urgent need for novel formulation to eliminate these bacterial communities. Herein we fabricated light controllable chitosan micelles loading with thymol (T-TCP) for elimination of biofilm. Due to the exterior chitosan, T-TCP micelles easily bind to negative biofilm through electrostatic interaction and efficiently deliver the essential oil payloads. Under irradiation, T-TCP micelles generated ROS, which triggered simultaneous thymol release and also resulted in additional ROS-inducing bactericidal effects, both effectively eradicating biofilms of Listeria monocytogenes and Staphylococcus aureus. This formulation provided a platform for other water-insoluble antimicrobials and might be used as a potent and controllable solution to biofilm fighting.

Depression, a mental illness characterized by persistent feeling of sadness and loss of interest, has been a serious health problem worldwide. Manipulation of the microbiota by probiotics and prebiotics represents a novel emerging strategy for the treatment of various psychiatric disorders such as major depressive disorders. Here, we show that one water-soluble polysaccharide from Ginkgo biloba leaves (GPS) reduced stress-induced depression and reversed gut dysbiosis. Similar to the antidepressant paroxetine, GPS significantly reduced the immobility times in the tail suspension test (TST) and forced swimming test (FST) and anxiety-like behavior in the open field test (OFT). Consistent with the improvement of depression-like behavior above, GPS mice had elevated serotonin and dopamine levels in multiple brain regions including the hippocampus, cerebral cortex and olfactory bulb, relative to unpredictable chronic mild stress (UCMS) treatment mice. GPS treatment could alleviate the stress-induced reduction in the density of serotonin-positive and dopamine-positive cells. Fecal microbiome transplant (FMT) combined with antibiotic treatment showed that the anti-depressant activity of GPS had a causal relationship with intestinal microbes. By performing a pyrosequencing-based analysis of bacterial 16S rRNA (V3 + V4 region) in fecal of the mice, the results showed that GPS reversed depression-associated gut dysbiosis and increased the richness of Lactobacillus species which has been proven to be a path to relieve depression. Our results demonstrated that the polysaccharide from Ginkgo biloba leaves might be a promising pharmacotherapeutic candidate for treating depression.

Pursuit of novel effective antidepressants is an urgent task. Poria cocos (Schw.) Wolf (PCW) is a traditional herb with antidepressant effects. Polysaccharides designated PCWPW and PCWPS were purified from PCW by DEAE-52 cellulose chromatography. Their structures were characterized using physicochemical and spectral methods. Chemical analysis indicated that PCWPW (37,154 Da) and PCWPS (186,209 Da) were mainly composed of mannose, glucose, galactose and fucose. Their antidepressant activities were evaluated by tail suspension test (TST), forced swimming test (FST) with chronic unpredictable mild stress (CUMS) model mice. To investigate the antidepressant mechanism, the neuroprotective and immunomodulation effects were assessed by MTT method. Results showed that PCWPW and PCWPS possess obvious antidepressant effects and can suppress ConA-stimulated T cell proliferation in a dose-dependent manner. In addition, PCWPS could protect the PC12 cells from H2O2-induced damage and suppress LPS-induced B cell proliferation. These findings implied that PCWPW and PCWPS might be a candidate for developing antidepressant or immunosuppressive agents in food and pharmaceutical industries.

Two polysaccharides JCS-1 and JCS-2 were successfully purified by DEAE-52 Cellulose chromatography from Zizyphus jujuba cv. Jinchangzao. Their structures were analyzed by high performance liquid chromatography (HPLC), high-performance gel permeation chromatography (HPGPC), nuclear magnetic resonance (NMR), and fourier transform infrared (FT-IR) spectroscopy. Further, eight sulfated derivatives are prepared by chlorosulfonic acid-pyridine (CSA-Pyr). Structural analysis revealed that both JCS-1 and JCS-2 were size uniform polysaccharides with the average molecular weight (Mw) of 71.75 kDa and 357.39 kDa, respectively. JCS-1 mainly has galacturonic acid (GalA) composition, and also contains a small amount of galactose (Gal) and arabinose (Ara), and their molar ratio is 39.04:1.26:1.39. JCS-2 was composed of GalA, mannose (Man), rhamnose (Rha), Ara and Gal, at a molar ratio of 19.87:2.07:1.77:1.65:1.16. Activity studies indicate that both natural polysaccharides and sulfated modified polysaccharides have immunomodulatory activity, while sulfated modified polysaccharides are stronger. Moreover, the sulfated polysaccharides significantly prolonged partial thromboplastin time (APTT) and thrombin time (TT) clotting times, but did not alter prothrombin time (PT) clotting time. The degree of substitution of polysaccharides seemed to be closely related to their biological characteristics. Sulfated modification represents an effective method of enhancing the immunomodulatory and anticoagulant activities of jujuba polysaccharides.

It is well known that the photothermal conversion performance of solar-driven interfacial water evaporation systems is known to have a stronger photothermal conversion performance than suspended water evaporation systems due to their relatively strong ability to suppress overall heat loss. Natural polymer chitosan and gelatin can form a three-dimensional interpenetrating network (IPN) sponge to provide an interface for water evaporation due to strong hydrogen bonding and electrostatic attraction interaction. However, the lack of effective light absorption, the intrinsic short lifetime, and the poor photothermal conversion greatly compromise their steam generation performance. Here, we fabricated a chitosan/gelatin-based IPN sponge incorporated with melanin-coated titania hollow nanospheres (CG@MPT-h) as a solar thermal converter, which is designed to exhibit a unique cavity structure and vertical channels. The cavity structure of melanin-coated titania acts as a solar thermal transducer, while the chitosan/gelatin-based IPN sponge acts as a single-pass water pump. A water hyacinth-inspired evaporation system shows outstanding steam generation performance, and the highest steam generation rate was 3.17 kg m-2 h-1 under a 2.5 sun illumination because of the cavity enhancement effect, far above TiO2 particles and reported photo-thermal conversion materials. More importantly, the embedding of MPT-h nanoparticles in the IPN sponge effectively inhibits the growth of bacteria in the vertical channels, resulting in an antibacterial solar-driven water evaporator. This advanced sponge provides a cost-effective and practical sustainable energy technique for solar-driven wastewater treatment.

Lycium barbarum polysaccharides (LBPs) are known for their beneficial effects on diabetes, NAFLD and related chronic metabolic diseases induced by high-fat diet (HFD). However, the relevant researches are mainly about the whole crude polysaccharides, the specific active ingredient of LBPs and its bioactivity have been rarely explored. Herein, a homogeneous polysaccharide (LBP-W) was isolated and purified from crude LBPs. Structure characterizations indicated that LBP-W contained a main chain consisting of a repeated unit of →6)-β-Galp(1 → residues with branches composed of α-Araf, β-Galp and α-Rhap residues at position C-3. The objective of this study was to evaluate the anti-obesogenic effect of LBP-W and figure out the underlying mechanisms. In vivo efficacy trial illustrated that LBP-W supplements can alleviate HFD-induced mice obesity significantly. Gut microbiota analysis showed that LBP-W not only improved community diversity of intestinal flora, but also regulated their specific genera. Moreover, LBP-W can increase the content of short-chain fatty acids (SCFAs), a metabolite of the intestinal flora. In summary, all these results demonstrated that the homogeneous polysaccharide purified from L. barbarum could be used as a prebiotic agent to improve obesity by modulating the composition of intestinal flora and the metabolism of SCFAs.

Probiotics were found to be effective in ameliorating the microbial dysbiosis and inflammation caused by intestinal pathogens. However, biological challenges encountered during oral delivery have greatly limited their potential health benefits. Here, a model probiotic (

We explored the possibility of improving the viability of Akkermansia muciniphila by encapsulating it in succinate-grafted alginate doped with epigallocatechin-3-gallate (EGCG). In this study, the determined surface properties of microcapsules and modified materials and the measured viability of probiotics after spray drying showed that the modified sodium alginate made the surfaces of microcapsules smoother and denser during the spray drying, thus preventing damages. EGCG enhanced the antioxidant capacity of probiotics by filling the pores inside microgels. Moreover, we analyzed the long-term storage vitality changes, oxidation resistance, uniformity, particle size and Zeta potential of microcapsules and found that spray-dried modified sodium alginate microcapsules with EGCG showed the better storability and stability. In addition, we experimentally analyzed the resistances of different microcapsules to the gastrointestinal fluid and found that EGCG-modified sodium alginate microcapsules better protected the probiotic activity from gastrointestinal fluid. This study provides a slimming product with industrial application potential.

Although advanced photocatalysts have been developed for water disinfection, photocatalytic activity is still limited owing to the difficulty of recycling nanoparticles and the high recombination rate of photogenerated electron-hole pairs. In this paper, efficient and recyclable CoFe2O4/CoFe2S4/MgBi2O6 (CFO/CFS/MBO) magnetic fibers (MNFs) photocatalyst with p-n-p type heterojunction are obtained by a simple hydrothermal method. As expected, when the optimal concentration of CFO/CFS/MBO was 0.5 mg/mL, the antibacterial rate reached 99.8% toward Methicillin-resistant Staphylococcus aureus (MRSA) after 60 min visible light irradiation. The optimal sample 30% CFO/CFS/MBO composite can degrade 82.7% Cefotaxime sodium (CTX) in 60 min. The mechanism was shown to be the severe damage of bacterial cell membranes and decomposition of antibiotic molecules caused by ROS generated by CFO/CFS/MBO photocatalyst under visible light irradiation. Due to the p-n-p heterojunction structural characteristics and abundant oxygen vacancies, CFO/CFS/MBO possessed a stronger absorption capacity of visible light and enhanced photo-generated carrier separation efficiency, which has a remarkably positive impact on the ability of photo-generated ROS. PL and EIS revealed the improvement of the separation efficiency of photogenerated carriers. LC-MS analysis, EPR and scavenger experiments verified the intermediate product, active species and photodegradation pathway in the photocatalytic process. Such recyclable and highly efficient CFO/CFS/MBO MNFs photocatalysts have promising applications in wastewater treatment.

Accompanied by overproduction of oxidants and reduction of pH, inflammation is closely related to many diseases such as cancer, atherosclerosis, and asthma. Besides chemotherapeutic agents, the potential regulative role of autophagy in inflammation is being actively investigated. RNA interference (RNAi)-based gene therapy is widely explored for clinical therapy but seriously restricted by lack of suitable carriers. In this study, we synthesized a hyaluronan-based ROS-sensitive polymer which was expected to release loaded chemical drugs in inflammatory environment and further developed a stable and nontoxic co-delivery nanosystem of siRNA targeting autophagy suppressive gene and chemotherapeutic agents. The in vitro transfection study of this nanosystem revealed improved intracellular accumulation of siRNA and excellent gene silencing efficacy comparable to that of conventional cationic liposome. Moreover, the mRNA expression of inflammatory cytokines was remarkably decreased by our nanosystem. Considering its biocompatibility, transfection efficacy, and anti-inflammatory capability, this co-delivery nanosystem proclaimed to be a promising combined therapeutic strategy for enhanced anti-inflammatory therapy.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common causes of hospital infection. Here, we showed that hyaluronic acid modified organic metal framework material ZIF-8 could be a Trojan horse of vancomycin (Van) for effective treatment of MRSA infections. The Van-loaded nanoparticles were readily up-taken by macrophages via a CD44-mediated process and collapsed in the acidic condition of endosome/lysosome, as a consequence, it could eradicate MRSA with high efficiency in macrophages. This drug delivery system with negligible toxicity could resolve MRSA infections in a well-established mouse pneumonia model.

Heparin (HP) has enormous potential for clinical medication applications owing to its anticoagulant activity. However, the strong anticoagulant capacity of HP also leads to some side effects. Herein, a photocaged derivative (HP-DMNB) of HP was synthesized for light control of its anticoagulant activity. The synthesized HP-DMNB was characterized by NMR and FTIR analysis, which confirmed the successful modification of HP with the photocleavable 4,5-dimethoxyl-2-nitrobenzyl (DMNB) groups. After the modification, the molecular weight of HP-DMNB (DS = 0.34%) changed from 61 to 71 kDa. Anticoagulant activity analysis showed that HP-DMNB had a reduced anticoagulant capacity compared with commercial HP, while its anticoagulant activity will regain after releasing the free carboxyl groups of HP under UV light. In addition, HP-DMNB and its UV irradiated products were observed to possess good biocompatibility through the MTT assays and live-dead assays with HaCaT cells, which may have impacts on the clinical medication applications of HP.

Aminoglycosides are often subtherapeutic to intracellular infections due to their high hydrophilicity. Here we used hyaluronic acid (HA) as a carbohydrate carrier of the aminoglycoside antibiotic, amikacin (AM) to deal with intracellular bacterial infections. The hyaluronan-amikacin conjugate (HA-AM) was synthesized by 'click' reaction between HA-propargyl amide (HAPA) and AM-azide. This conjugate with little cytotoxicity retained antibiotic effects on planktonic bacteria and showed better intracellular bactericidal activity than the antibiotic did. In addition, this conjugate was more efficient in reducing bacteria burden in an in vivo acute infection model than amikacin did. These results suggested that hyaluronic acid conjugation could reduce the dosage of antibiotic in treatment of intracellular bacterial infection, and further helping to alleviate the emergence of drug resistance in bacteria due to a long-term, high-dosage treatment.

It is well known that the adsorption capacity of particles is stronger than that of film due to the high specific surface area. Nonetheless, it is a bit different in some cases because of the plane enhancement effect of film. The third-generation cephalosporin are commonly used for either prevention or treatment of bacterial infections. These antibiotics, which have been discharged into various water environment, have created a lot of serious problems in our world. Adsorption of cefotaxime (CTX) in water by the chitosan particles (CSp) and films (CSf) were explored. The samples were characterized by scanning electron microscopy, the nitrogen adsorption isotherms, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and others. Various experimental conditions (pH, adsorption time, molecular weight of CSf, initial antibiotic concentrations, the number of films and foreign ions) presented an important influence on CTX removal. The pseudo-second-order kinetics and Freundlich isotherm models better illustrated the adsorption behavior of CTX on CSf, and the highest adsorption capacity was 1003.64 mg g−1, far above CSp (648.05 mg g−1) and these reported adsorbents. The reusability experiments revealed that CSf had passable regeneration and continuous usage performance. Multiple analysis factors suggested that the mechanism of CTX adsorption on CSf was mainly based on plane strengthening effect, electrostatic attraction, nucleophilic addition reaction and hydrogen bonding. These findings showed that CSf was an efficient and reusable adsorbent for antibiotics elimination in water.

Current studies have revealed the excellent moisture absorption-retention capacity of hyaluronan (HA); however, HA is easily degraded by hyaluronidase on the surface of skin. So, it is very necessary to develop an alternative derivative with low cytotoxicity and resistance to hyaluronidase. Herein, a HA decorated with photocaged groups was synthesized. The moisture absorption-retention capacity and hyaluronidase resistance of photocaged HA (HA-DMNB) and products of HA-DMNB irradiated by ultraviolet for different time (IHA-DMNB), were investigated. Results show that HA-DMNB is more resistant to hyaluronidase than HA, and HA-DMNB could release free carboxyl groups of HA upon ultraviolet to bond with H2O. More importantly, HA-DMNB was protective against UV light. In addition, HA-DMNB and IHA-DMNB were observed to be nontoxic to HaCat cells. This study indicates that HA-DMNB may be effectively used as a moisture-preserving reagent.

Antibiotic therapy is usually not recommended for salmonellosis, as it is associated with prolonged fecal carriage without reducing symptom duration or severity. Here we show that antibiotics encapsulated in hydrogen sulfide (H2S)-responsive glycovesicles may be potentially useful for the treatment of salmonellosis. The antibiotics are released in the presence of Salmonella, which is known to produce H2S. This approach prevents the quick absorption of antibiotics into the bloodstream, allows localized targeting of the pathogen in the gut, and alleviates disease symptoms in a mouse infection model. In addition, it reduces antibiotic-induced changes in the gut microbiota, and increases the abundance of potentially beneficial lactobacilli due to the release of prebiotic xylooligosaccharide analogs., Antibiotic therapy is usually not effective for salmonellosis. Here, the authors present an approach that may be useful for the treatment of salmonellosis, consisting of hydrogen sulfide (H2S)-responsive glycovesicles that release antibiotics in the presence of Salmonella in the gut.

Polysialic acid (PSA), a non-immunogenic and biodegradable natural polymer, is prone to hydrolysis under endo-lysosomal pH conditions. Here, we synthesized an intracellular pH-sensitive polysialic acid-ursolic acid conjugate by a condensation reaction. To further test the drug loading capability, we prepared paclitaxel-loaded polysialic acid-based amphiphilic copolymer micelle (PTX-loaded-PSAU) by a nanoprecipitation method. Results showed PTX-loaded-PSAU exhibited well-defined spherical shape and homogeneous distribution. The drug-loading was 4.5% with an entrapment efficiency of 67.5%. PTX released from PTX-loaded-PSAU was 15% and 42% in 72 h under simulated physiological condition (pH 7.4) and mild acidic conditions (pH 5.0), respectively. In addition, In vitro cytotoxicity assay showed that PTX-loaded-PSAU retained anti-tumor (SGC-7901) activity with a cell viability of 53.8% following 72 h incubation, indicating PTX-loaded-PSAU could efficiently release PTX into the tumor cells. These results indicated that the pH-responsive biodegradable PTX-loaded-PSAU possess superior extracellular stability and intracellular drug release ability.

Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, cancer, and other diseases. In this study, two polysaccharides RPAPW1 and RPAPW2 were isolated from Radix Paeoniae Alba by DEAE-52 cellulose chromatography and G-25 sephadex. According to physicochemical methods, NMR and methylation analysis, RPAPW1 and RPAPW2 were established to be α-glucans consisting of predominant 4-linked α- Glc residues branched at O-6 and contained trace amount of protein and uronic acid. Immunological tests indicated that RPAPW1, RPAPW2 and could promote splenocyte proliferation and RAW264.7 phagocytic activity. In vitro, RPAPW1 and RPAPW2 elicited a week reducing power, DPPH scavenging activity and could not protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPW1 and RPAPW2 had the potential to be a natural immunopotentiating and antioxidant supplement for preparing functional foods and nutraceuticals.

The emergence of biofilm-associated resistance of microbes to traditional antibiotics has resulted in an urgent need for novel antimicrobial agents. Herein we developed a facile approach to overcome the problem through chitosan–streptomycin gold nanoparticles (CA NPs). The synthesized CA NPs were characterized by ultraviolet-visible absorption spectra (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS). The resulting CA NPs maintained their antibiofilm activities towards Gram-positive organisms. More importantly, CA NPs damaged established biofilms and inhibited biofilm formation of Gram-negative bacteria pathogens. Mechanistic insight demonstrated that CA NPs rendered streptomycin more accessible to biofilms, thereby it was available to interact with biofilm bacteria. Additionally, CA NPs were observed to kill more biofilm-dispersed cells than CS conjugate or streptomycin and inhibit the planktonic cell growth of Gram-positive and -negative bacteria. Thus, this work represents an innovative strategy whereby gold nanoparticles linked to carbohydrate–antibiotic conjugates can overcome antibiotic resistance of microbial biofilms, suggesting the potential of using the generated CA NPs as antimicrobial agents for bacterial infectious diseases.

Glycosylation is unarguably the most important reaction in the field of glycochemistry. Photo-initiated reactions hold extraordinary potential in organic synthesis. Herein we report a novel light-driven strategy for the activation of thioglycosides via the merger of a CF3 radical pathway followed by the subsequent glycosylation with glycosyl acceptors. This protocol could efficiently activate thioglycosides, thereby greatly enhancing the substrate scope of reactions. In particular, the glycosylation reactions, which are completely inert under the existing photo-induced glycosylation conditions, proceeded smoothly in high yields. Many common protective groups were well tolerated under the coupling conditions. Both UV and visible light or even sunlight were used as the source of light for the reactions. The high efficiency of this light-driven glycosylation protocol was further highlighted by the rapid one-pot sequential assembly of oligosaccharides.

The removal of tetracycline (TC) by novel magnetic graphene oxide/ZnO nanocomposites (MZ) was explored. In order to study the feasibility of MZ as an adsorbent and photocatalyst to remove tetracycline, a series of experiments were carried out. Fortunately, MZ shows outstanding adsorption capacity for TC and can be easily separated from water. The pseudo-second-order kinetics model can explain the adsorption process of TC well, and the maximum adsorption capacity is 1590.28 mg g−1. Analyzing various results, it was found that the adsorption mechanism can be explained by electrostatic attraction, π-π interaction, hydrogen bonding, cation exchange, and complexation. In the experiments of photocatalytic degradation of TC, graphene oxide acts as the framework and promotes the electron transfer, ZnO acts as an effective photocatalyst. In addition, MZ remained relatively high levels of removal after four cycles. The information provided by these results confirms the great potential of MZ as a highly efficient adsorbent and photocatalyst in removing tetracycline pollutants in water.

Antibiotic and bacteria pollutions widely exist in aquatic environment, and pose a great threat to human health. The effective removal of antibiotic and microbial contamination from water is of great importance in global public health. In this study, black melamine-based sponge (AMS) was prepared by calcination method. Tetracycline (TC) and Salmonella were picked as models to investigate the antibiotic degradation and antibacterial property of AMS, and the possible reaction mechanism of AMS photocatalyst in the removal of tetracycline and Salmonella was also investigated. Compared with conventional method for fabricating photocatalyst materials, the current strategy for fabricating AMS is low-cost, rapid, low energy input, easy to operate and does not involve any additional additives. The results indicated that AMS possessed porous structure and obvious visible-light absorption, and exhibited excellent photocatalytic activity with the rate constant of 0.2059 min−1 for the removal of tetracycline and 98.1% inactivation rate of Salmonella under visible-light irradiation. Moreover, the analysis of various experiment results indicated that the degradation of TC by AMS was mainly attributed to photo-generated radicals, while the destruction of Salmonella was due chiefly to the photothermal conversion performance of AMS. This kind of low-cost and high-efficiency melamine-derived sponge has great potential to degrade antibiotics and destroy bacteria, verifying AMS is a promising water purification photocatalyst.

Antibiotics are powerful weapons to fight against bacterial infections, while most of them lack of selective targeting towards pathological site which could restrict their antibacterial efficacy. To overcome this challenge, an antimicrobial levofloxacin(LF)was conjugated onto hyaluronic acid (HA) moieties via an o-phenylenediamine linker to prepare a NO-sensitive nanosystem (HA-NO-LF) in this study. The HA-NO-LF nanomicelles could enter host cells via a CD44 mediated endocytosis and release drug gradually upon exposure to endogenous NO. Furthermore, the more promising therapeutic effect of the nanomicelles in ameliorating inflammatory levels was observed in a mouse pneumonia model than that of LF. These results suggest that the HA-NO-LF nanomicelles may exert potent curative effect in infectious diseases.

Adsorption of tetracycline (TC) and cefotaxime (CTX) by novel NiFe2O4-COF-chitosan-terephthalaldehyde nanocomposites film (NCCT) was explored. To assess the feasibility of NCCT as a potential adsorbent for TC and CTX removal, a series of adsorption experiments were conducted. These results showed that the chemical crosslink of chitosan with terephthalaldehyde (TPA) restricted NCCT degradation of acid. In addition, NCCT as a film adsorbent could be separated completely in only 2 s without mass loss, much faster than any other magnetic materials. The abundant functional groups of chitosan, COF and TPA could significantly improve the adsorption capacity of NCCT on antibiotics. The pseudo-second-order kinetics model better illustrated the adsorption of TC and CTX onto NCCT, and the maximum adsorption capacity are 388.52 mg g−1 and 309.26 mg g−1, respectively. The nanocomposites film NCCT also exhibit excellent reproducibility after six adsorption cycles. In addition, various analysis results implied the adsorption mechanism of TC on NCCT was mainly through complexation, cation exchange, electrostatic attraction, hydrogen bonding and the π–π interaction. For CTX, the mechanism of adsorption included condensation reaction, electrostatic attraction, hydrogen bonding and π–π interaction. This kind of high-efficiency and novel nanocomposites film adsorbents can be ultrafastly separated from water, verifying NCCT has huge potential in water treatment for antibiotic contaminants removal.

Scope The prevalence of obesity and related disorders has vastly increased throughout the world and prevention of such circumstances thus represents a major challenge. Here, it has been shown that one protein-bound β-glucan (PBG) from the edible mushroom Coriolus versicolor can be a potent anti-obesity component. Methods and results PBG can reduce obesity and metabolic inflammation in mice fed with a high-fat diet (HFD). Gut microbiota analysis reveals that PBG markedly increases the abundance of Akkermansia muciniphila, although it does not rescue HFD-induced change in the Firmicutes to Bacteroidetes ratio. It appears that PBG alters host physiology and creates an intestinal microenvironment favorable for A. muciniphila colonization. Fecal transplants from PBG-treated animals in part reduce obesity in recipient HFD-fed mice. Further, PBG is shown to upregulate expression of a set of genes related to host metabolism in microbiota-depleted mice. Conclusion The data highlight that PBG may exert its anti-obesity effects through a mirobiota-dependent (richness of specific microbiota) and -independent (modulation of host metabolism) manner. The fact that C. versicolor PBGs are approved oral immune boosters in cancers and chronic hepatitis with well-established safety profiles may accelerate PBG as a novel use for obesity treatment.

Chronic mild stress (CMS) model is most similar to the depression human suffered in daily life. Strong evidence proved the important role of hippocampal synaptic plasticity in the mechanism of depression. This study investigated the effect of CMS on synaptic plasticity in hippocampus. Our results showed that CMS impaired spatial memory and exploring ability, disturbed the release of neurotransmitters including 5-hydroxytryptamine (5-HT) and dopamine (DA), reduced the density of synaptic vesicle in inner molecular layer, increased the number of thin spines in inner and outer molecular layer, whereas did not affect the density of spine apparatus, the above mentioned were probably related to the reduction of astrocytes and activation of microglial cells.

In this paper, a novel photo-controlled drug-loaded nanomicelles were self-assembled by the amphiphile of hyaluronan-o-nitrobenzyl-stearyl chain (HA-NB-SC) with doxorubicin (DOX) encapsulated within the hydrophobic core. DOX-loaded HA-NB-SC nanomicelles are ∼139 nm in diameter. CD44-overexpressed HeLa cells can easily take up HA-NB-SC micelles through recognition of HA moiety. DOX-loaded HA-NB-SC nanomicelles could be disassembled upon UV light (365 nm) and consequently, release DOX at desired pathological sites. Furtherly, nitrosobenzaldehyde derivative, photo-induced products of HA-NB-SC and DOX could inhibit the proliferation of HeLa cells together. This strategy may shed some light on delivery of hydrophobic anti-cancer drugs in a controlled manner.

The anticancer properties of supramolecular nanofibers of taxol in hydrogels could be manipulated by the kinetics of hydrogel formation.

Rhizoma Acori Tatarinowii is widely used in traditional Chinese medicine. In this study, three novel polysaccharides designated RATPW, RATPS1 and RATPS2 were isolated from Rhizoma Acori Tatarinowii by DEAE-52 cellulose chromatography. Their structures were characterized using physicochemical and spectral methods. Chemical analysis indicated that RATPW (6.5×10(3)Da) mainly composed of glucose and fructose. RATPS1 (1.5×10(5)Da) contained galactose and arabinose, while RATPS2 (5.3×10(4)Da) contained ∼49.5% galacturonic acid along with rhamnose, fructose, galactose, and arabinose. In vitro, RATPS2 showed the most significant scavenging activity on DPPH and hydroxyl radical. Three polysaccharides could protect the PC12 cells from H2O2-induced damage. Immunological tests indicated that both RATPW and RATPS2 significantly stimulated NO production and phagocytic activity in RAW264.7, and promoted splenocyte proliferation. These data suggested that polysaccharides RATPW and RATPS2 had the potential as novel natural sources of antioxidative and immunopotentiating agents.

In this study, 2-(N-pyrrolidine-alkyl) tanshinones bearing pyrrolidine groups were synthesized and the antibacterial mechanism was explored. These derivatives selectively elicited antibacterial activity against Gram-positive bacteria. Moreover, their antibacterial activities were time-, concentration-dependent and persistent. It appeared that Fenton-mediated hydroxyl radicals were involved, and the disruption of cell membranes was observed. This study indicates that 2-(N-pyrrolidine-alkyl) tanshinones might be potential candidates as antibacterial agents.

Significance and Impact of the Study: This study has shown the synergistic effect of four components of essential oil (thymol, eugenol, berberine and cinnamaldehyde) combined with streptomycin on planktonic and biofilm-associated food-borne pathogens Listeria monocytogenes and Salmonella Typhimurium. These findings indicate that combination of specific components of essential oils with streptomycin may provide alternative methods to overcome the problem of food-borne bacteria both in suspension and in biofilm. Abstract Essential oils have been found to exert antibacterial, antifungal, spasmolytic, and antiplasmodial activity and therapeutic effect in cancer treatment. In this study, the antibacterial activities of four main essential oils' components (thymol (Thy), eugenol (Eug), berberine (Ber), and cinnamaldehyde (Cin)) were evaluated against two food-borne pathogens, Listeria monocytogenes and Salmonella Typhimurium, either alone or in combination with streptomycin. Checkerboard assay demonstrated that Thy and Cin elicited a synergistic effect with streptomycin against L. monocytogenes, while a synergy existed between Cin or Eug and streptomycin against Salm. Typhimurium. Further experiments showed that this synergy was sufficient to eradicate biofilms formed by these two bacteria. Thus, our data highlighted that the combinations of specific components from essential oils and streptomycin were useful for the treatment of food-borne pathogens, which might help prevent the spread of antibiotic resistance through improving antibiotic effectiveness.