Isolation and identifi cation of antimicrobial metabolites from sea anemone-derived fungus Emericella sp.SMA01

Marine symbiotic fungi represent an intriguing source of discovery of novel secondary metabolites with various biological activities.Sea anemones are benthic marine invertebrates,however,the cultivable symbiotic fungi residing in the sea anemones are paid few attentions compared to those derived from their cnidarian counterparts.Here we show the identification of antimicrobial secondary metabolites from the sea anemone-derived symbiotic fungi.Out offive isolated fungal strains,only the strain SMA01 showed strong antimicrobial activities,which was assigned into the genus Emericella based on the morphological characteristics and the ITS sequencing.Media swift from liquid fermentation to solid rice medium presented little influence on its antibacterial activity.A chemical investigation of the ethyl acetate extract of the Emericella sp.SMA01 led to discovery of the primary antibiotic metabolite phenazine-1-carboxylic acid.The IC_(50) values of the phenazine-1-carboxylic acid against Phytophthora capsici,Gibberella zeae,and Verticillium dahliae were determined to be 23.26-53.89μg/mL.To the best of our knowledge,this was the first report of Emericella sp.in sea anemones.The current study may benefit understanding of the defensive chemical interactions between the symbiotic fungi and their host sea anemones.

Synthesis and performance of carbon-modified LiFePO_4 using an in situ PVA pyrolysis procedure

LiFePOa/carbon composite cathode material was prepared by granulating and subsequent pyrolysis processing in N2 atmosphere with polyvinyl alcohol （PVA） as the carbon source. The influences of carbon content on the microstructure and battery performance were investigated. Single LiFePO4 phase and amorphous carbon can be found in the products. A special micro-morphology of the optimum sample was observed. The discharge capacity of the cell with the optimum cathode was 135 mAh.g^-1, close to the charge capacity of 153 mAh.g^-1 at 17 mA.g^-1. The influence of ambient temperature on the cell capacity was investigated. The temperature dependence of its electrochemical characteristic was evaluated by using AC impedance spectroscopy. A new equivalent circuit based on the charge and mass transfer control process in an electrode was proposed to fit the obtained AC impedance spectra. The tendency of every element in the equivalent circuit was used to interpret the temperature dependence of the capacity of the optimum cathode.

Simultaneous determination of ten nucleosides and bases in Ganoderma by micellar electrokinetic chromatography

Ganoderma(lingzhi)is a famous herbal medicine and edible supplement in oriental countries for a long history.In this study,a simple micellar electrokinetic chromatography(MEKC)method was established for the analysis of nucleosides and bases,the major bioactive components in Ganoderma for the first time.By optimizing the borate concentration,the sodium dodecyl sulfate(SDS)concentration and the pH value of running buffer,10 nucleosides and bases achieved an ideal separation.In real sample analysis,the developed method was successfully used to determine the 10 target analytes in 23 batches of Ganoderma samples from different regions.Results indicated that contents of 10 investigated analytes in each sample showed obvious variation.The principal components analysis(PCA)and hierarchical cluster analysis(HCA)analysis classified the samples into three groups,and the HCA tree visualized the relationships which was mainly contributed by geographical partition.The results indicated geographical origin to be an important factor that affect the accumulation of nucleosides and bases in Ganoderma.In summary,this study provides a simple and practical strategy for quality assessment and cultivation reference of Ganoderma.

The deubiquitinating enzyme 13 retards non-alcoholic steatohepatitis via blocking inactive rhomboid protein 2-dependent pathway

Nowadays potential preclinical drugs for the treatment of nonalcoholic steatohepatitis(NASH)have failed to achieve expected therapeutic efficacy because the pathogenic mechanisms are underestimated.Inactive rhomboid protein 2(IRHOM2),a promising target for treatment of inflammation-related diseases,contributes to deregulated hepatocyte metabolism-associated nonalcoholic steatohepatitis(NASH)progression.However,the molecular mechanism underlying Irhom2 regulation is still not completely understood.In this work,we identify the ubiquitin-specific protease 13(USP13)as a critical and novel endogenous blocker of IRHOM2,and we also indicate that USP13 is an IRHOM2-interacting protein that catalyzes deubiquitination of Irhom2 in hepatocytes.Hepatocyte-specific loss of the Usp13 disrupts liver metabolic homeostasis,followed by glycometabolic disorder,lipid deposition,increased inflammation,and markedly promotes NASH development.Conversely,transgenic mice with Usp13 overexpression,lentivirus(LV)-or adeno-associated virus(AAV)-driven Usp13 gene therapeutics mitigates NASH in 3 models of rodent.Mechanistically,in response to metabolic stresses,USP13 directly interacts with IRHOM2 and removes its K63-linked ubiquitination induced by ubiquitin-conjugating enzyme E2N(UBC13),a ubiquitin E2 conjugating enzyme,and thus prevents its activation of downstream cascade pathway.USP13 is a potential treatment target for NASH therapy by targeting the Irhom2 signaling pathway.

Freeze-drying and hot-pressing strategy to embed two-dimensional Ti_(0.87)O_(2) monolayers in commercial polypropylene films with enhanced dielectric properties

The dielectric capacitor has been widely used in advanced electronic and electrical power systems due to its capability of ultrafast charging–discharging and ultrahigh power density.Nevertheless,its energy density is still limited by the low dielectric constant(≈2.2)of the commercial dielectric polypropylene(PP).The conventional enhancement strategy by embedding inorganic fillers in PP matrix is still difficult and challenging due to that PP hardly dissolves in any inorganic/organic solvent.In this work,we develop a new strategy including freeze-drying,surface functionalization,and hot-pressing to incorporate Ti_(0.87)O_(2) monolayers in PP film.A series of uniform composited Ti_(0.87)O_(2)@PP film has been successfully fabricated with Ti0.87O2 content range of 0–15 wt%.The maximum dielectric constant of the as-prepared Ti_(0.87)O_(2)@PP film is 3.27 when the Ti_(0.87)O_(2) content is 9 wt%,which is about 1.5 times higher than that of pure PP.Our study provides a feasible strategy to embed two-dimensional material into commercial PP thin-film with superior dielectric performance for practical application.

Constructing a"pea-pod"-like nanostructure to provide valid conductive matrix and volume change accommodation for silicon anode in lithium ion batteries

A"pea-pod"-like composite of graphene-wrapped silicon nanoparticles(P–Si@GS)was successfully prepared via a new and facial technique utilizing freeze-drying and subsequent solvothermal process.The cross-linked"pods"formed by curled few-layer graphene sheets constituted a conductive network,in which silicon nanoparticles were tightly wrapped.The unique graphene-wrapped structure with mesopores on the surface can effectively enhance the conductivity of silicon,alleviate its volume effect and provide rapid transport channels for electrons and ions,thus resulting in excellent electrochemical performance.The strategy of combining freeze-drying and solvothermal methods is facile,low-cost and effective,which provides new ideas for the preparation of highperformance graphene-wrapped nanoparticles composites.