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Pulmonary arterial hypertension (PAH) is a chronic disease characterized by a progressive elevation in mean pulmonary arterial pressure. This occurs due to abnormal remodeling of small peripheral lung vasculature resulting in progressive occlusion of the artery lumen that eventually causes right heart failure and death. Current therapeutic options for PAH are limited and focused mainly on reversal of pulmonary vasoconstriction and proliferation of vascular cells. Although these treatments can relieve disease symptoms, PAH remains a progressive lethal disease.Bone morphogenetic proteins (BMPs) and their receptors were required for PAH-induced right ventricular hypertrophy. Emerging data suggest that restoration of BMP type II receptor (BMPR2) signaling in PAH is a promising alternative that could prevent and reverse pulmonary vascular remodeling. BMPR2 mutations have been identified in >70% of familial and roughly 15% of sporadic PAH cases. Wingless (Wnt) are a family of secreted glycoproteins with varying expression patterns and a range of functions, Wnt signaling pathway is divided into canonical signaling pathway and non-canonical signaling pathway. A recent study reports that interaction between BMP and Wnt closely associated with lung development, those cascade coordination regulation stem cell fate which determine lung branching morphogenes. The promoting effect of BMPR2 on proliferation, survival, and motility of endothelial cells was through recruiting Wnts signaling pathway, the interaction between BMP and Wnt closely associated with lung development.Therefore, in this review, we outline the latest advances of BMP and Wnt signaling pathway in the pathogenesis of PAH and disease progression.

A fosmid metagenomic library containing 9.7 × 104 clones was constructed. A novel esterase, XtjR8, was isolated through functional screening. XtjR8 shared the maximum amino acid identity (44%) with acetyl-hydrolase from Streptomyces hygroscopicus, and was classified into family IV esterase. XtjR8 exhibited the highest hydrolytic activity for p-nitrophenyl acetate at 40 °C and pH 8.0, and presented more than 40% activity from 20 °C to 80 °C. More importantly, XtjR8 displayed the ability to hydrolyze both phthalate monoesters and diesters, this feature is extremely rare among previously reported esterases. Site-directed mutagenesis experiments revealed that the catalytic triad residues were Ser152, Glu246, and His276. Among them, Ser152 formed a hydrogen bond with dibutyl phthalate (DBP) by molecular docking, Gly84, Gly85, and Leu248 of conserved motifs formed hydrophobic interactions with DBP, respectively, which were important for the catalytic activity. Considering its wide range of temperature and hydrolytic potential toward phthalate esters, XtjR8 will be served as an interesting candidate for biodegradation and industrial applications.

CRISPR/Cas9 is one of the robust and effective gene manipulation tools which has been widely applied in various organisms. In this study, the plipastatin gene cluster was successfully expressed in genome-modified Bacillus subtilis 1A751 by disrupting the surfactin operon (srf) through CRISPR/Cas9 technology. The presumed plipastatin biosynthetic pathway was proposed based on the analysis of its biosynthetic gene cluster. Two new plipastatins were identified by a combination of ultra-high performance liquid chromatography-coupled electron spray ionization-tandem mass spectrometry and gas chromatography-mass spectrometry analyses, together with nine known plipastatins or their derivatives. The yield of plipastatin was as high as 1600 mg/L which is the highest reported to date. Antimicrobial experiments revealed that its methanolic extracts exhibited powerful inhibitory effects on the growth of the tested pathogens and fungi. The results from this investigation highlight the remarkable utility of CRISPR/Cas9 in mining new plipastatins and increasing the total plipastatin yield, providing a new pipeline for the industrial application of plipastatin.

A novel carboxylesterase gene, named dlfae4, was discovered and sequenced from a soil metagenomic library. The dlfae4 gene was composed of 1017 base pairs encoding 338 amino acid residues with a predicted molecular mass of 37.2 kDa. DLFae4 exhibited strong hydrolytic activity towards methyl ferulate under optimum pH and temperature conditions (pH 8.6, 50 °C) and displayed remarkable thermostability, with residual activity as high as 50% after incubation for 3 h at 60 °C. A family VIII esterase DLFae4 was found to contain a typical serine residue within the S-X-X-K motif, which serves as a catalytic nucleophile in class C β-lactamases and family VIII esterases. As a consequence of its high sequence similarity with β-lactamases, DLFae4 exhibited significant hydrolytic activity towards ampicillin. In addition, DLFae4 was found to be the first known member of family VIII carboxylesterases with phthalate-degrading ability. Site-directed mutagenesis studies revealed that Ser11, Lys14, and Tyr121 residues play an essential catalytic role in DLFae4. These new findings, which are of great importance for further in-depth research and engineering development of carboxylesterases, should advance the implementation of biotechnological applications.

To discover novel feruloyl esterases (FAEs) by the function-driven screening procedure from soil metagenome. A novel FAE gene bds4 was isolated from a soil metagenomic library and over-expressed in Escherichia coli. The recombinant enzyme BDS4 was purified to homogeneity with a predicted molecular weight of 38.8 kDa. BDS4 exhibited strong activity (57.05 U/mg) toward methyl ferulate under the optimum pH and temperature of 8.0 and 37°C. Based on its amino acid sequence and model substrates specificity, BDS4 was classified as a type-C FAE. The quantity of the releasing ferulic acid can be enhanced significantly in the presence of xylanase compared with BDS4 alone from de-starched wheat bran. In addition, BDS4 can also hydrolyze several phthalates such as diethyl phthalate, dimethyl phthalate and dibutyl phthalate. The current investigation discovered a novel FAE with phthalate-degrading activity and highlighted the usefulness of metagenomic approaches as a powerful tool for discovery of novel FAEs.

A novel lipolytic gene, estq7, was identified from a fosmid metagenomic library. The recombinant enzyme EstQ7 consists of 370 amino acids with an anticipated molecular mass of 42 kDa. Multiple sequence alignments showed that EstQ7 contained a pentapeptide motif GHSMG, and a putative catalytic triad Ser174–Asp306–His344. Interestingly, EstQ7 was found to have very little similarity to the characterized lipolytic enzymes. Phylogenetic analysis revealed that EstQ7 may be a member of a novel family of lipolytic enzymes. Biochemical characterization of the recombinant enzyme revealed that it constitutes a slightly alkalophilic, moderate thermophilic and highly active carboxylesterase against short chain fatty acid esters with optimum temperature 50 ℃ and pH 8.2. The Km and kcat values toward p-nitrophenyl acetate were determined to be 0.17 mM and 1910 S-1, respectively. Moreover, EstQ7 was demonstrated to have acyltransferase activity by GC-MS analysis. Homology modeling of the three-dimensional structure of this new enzyme showed that it exhibits a typical α/β hydrolase fold, and the catalytic triad residues are spatially close. Molecular docking reveled the interactions between the enzyme and the ligand. The high levels of lipolytic activity of EstQ7, combined with its moderate thermophilic property, and acyltransferase activity, render this novel enzyme a promising candidate biocatalyst for food, pharmaceutical and biotechnological applications.

An alkaline esterase, designated as EstXT1, was identified through functional screening from a metagenomic library. Sequence analysis revealed that EstXT1 belonged to the family VIII carboxylesterases and contained a characteristic conserved S-x-x-K motif and a deduced catalytic triad Ser56-Lys59-Tyr165. EstXT1 exhibited the strongest activity toward methyl ferulate at pH 8.0 and temperature 55°C and retained over 80% of its original activity after incubation in the pH range of 7.0-10.6 buffers. Biochemical characterization of the recombinant enzyme showed that it was activated by Zn2+ and Co2+ metal ion, while inhibited by Cu2+ and CTAB. EstXT1 exhibited significant promiscuous acyltransferase activity preferred to the acylation of benzyl alcohol acceptor using short-chain pNP-esters (C2-C8) as acyl-donors. A structure-function analysis indicated that a WAG motif is essential to acyltransferase activity. This is the first report example that WAG motif plays a pivotal role in acyltransferase activity in family VIII carboxylesterases beside WGG motif. Further experiment indicated that EstXT1 successfully acylated cyanidin-3-O-glucoside in aqueous solution. The results from the current investigation provided new insights for the family VIII carboxylesterase and lay a foundation for the potential applications of EstXT1 in food and biotechnology fields.

A novel carboxylesterase gene estyz5 was isolated from a soil metagenomic library. The recombinant enzyme EstYZ5 is 298 amino acids in length with a predicted molecular weight of 32 kDa. Sequence alignment and phylogenetic analysis revealed that EstYZ5 belongs to the hormone-sensitive lipase (HSL) family with a deduced catalytic triad of Ser144-Glu238-His268. EstYZ5 contains two conserved motifs, a pentapeptide motif GDSAG and a HGGG motif, which are typically found in members of the HSL family. Esterolytic activity of the recombinant enzyme was optimal at 30 °C and pH 8.0, and the kcat/Km value of the enzyme for the optimum substrate p-nitrophenyl butyrate was as high as 1272 mM-1·s-1. Importantly, EstYZ5 showed activity toward di(2-ethylhexyl) phthalate with complex side chains, which is rare for HSLs. Molecular docking simulations revealed that the catalytic triad and an oxyanion hole likely play vital roles in enzymatic activity and specificity. The phthalate-degrading activity of EstYZ5, combined with its high levels of esterolytic activity, render this new enzyme a candidate for biotechnological applications.

Non-extractable polyphenols (NEPPs) in pomegranate peel were released by acid hydrolysis followed by extraction using ethyl acetate (EtOAc). Ten NEPPs were identified in the hydrolysate using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Six compounds were then isolated from the EtOAc extracts whose structures were identified as β-sitosterol-3-O-glycoside (1), β-sitosterol (2), ursolic acid (3), corosolic acid (4), asiatic acid (5) and arjunolic acid (6) using a wide range of spectroscopic analyses. Compounds 4–6 were isolated for the first time from pomegranate peel. Antimicrobial experiments revealed that compound 3 and 5 showed significant antimicrobial activity against a range of pathogens, particularly compound 5 which exhibited selective inhibitive activity towards Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 16 μg/ml. The present study has provided new insights into the composition of bound chemicals in pomegranate peel and laid a foundation for improving its further processing and utilization.

CRISPR/Cas9 is one of the robust and effective gene manipulation tools which has been widely applied in various organisms. In this study, the plipastatin gene cluster was successfully expressed in genome-modified

Our previous work has reported that EstJ6 was a phthalate-degrading hydrolase. In the study, a random mutant library was constructed by two rounds of error-prone PCR, three mutants (ET1.1, ET2.1, and ET2.2) with enhanced hydrolytic activity against dibutyl phthalate (DBP) were obtained. The best mutant ET2.2, accumulated three amino acid substitutions (Thr91Met, Ala67Val, and Val249Ile) and exhibited 2.8-fold increase enzyme activity and 2.3-fold higher expression level. Meanwhile, compared with EstJ6, ET2.2 showed over 50% improvement in thermostability (at 50 °C for 1 h) and 1.2-fold increase in 50% methanol tolerance. Kinetic parameters analysis revealed that the Km value for ET2.2 decreased by 60% and the kcat/Km value increased by 166%. The molecular docking indicated that the shortening of hydrogen bond between Ser146-OH and DBP-CO, which may led to an increase in enzyme activity and catalytic efficiency, the enhancement of hydrophobicity of hydrophobic pocket was related to the improvement of organic solvents tolerance, and three hydrophobic amino acid substitutions Thr91Met, Ala67Val, and Val249Ile facilitated to improve the thermal stability and organic solvents tolerance. These results confirmed that random mutagenesis was an effective tool for improving enzyme properties and lay a foundation for practical applications of phthalate-degrading hydrolase in biotechnology and industrial fields.

Staphylococcus aureus is a common pathogen in foodstuffs, and an effective detection assay is therefore essential for ensuring food safety. In this study, we established a label-free loop-mediated isothermal amplification integrated G-quadruplex molecular beacon (LAMP-GMB) chemiluminescence method for S. aureus detection based on its nuc gene that encodes a thermostable nuclease. Target DNA was amplified using the LAMP technique; the result LAMP products were specially recognized by GMB detection probe, subsequently induced the release of G-rich sequence, and formed a complex spatial structure G-quadruplex. The structure can bind with hemin and catalyze the H2O2-mediated oxidation of luminol reagent to produce the chemiluminescence signal for chemiluminescent detection. Under the optimized conditions, the developed method showed a good linear relationship (R2 = 0.9882) in the range of 101-105 fg μL−1 and was able to detect as low as 10 fg μL−1 genomic DNA from S. aureus. Using spiked milk samples, the method exhibited a linear relationship (R2 = 0.9893) ranging from 5 × 101 to 5 × 107 CFU mL−1 with the limit of detection of 50 CFU mL−1. Importantly, the detection assay did not require the preparation and use of labeled primers for the LAMP reaction, increasing the reliability and efficiency of the assay. Therefore, the developed LAMP-GMB method has the potential to be widely applied to S. aureus monitoring work in food field.

It is crucial for service providers to improve user’s quality of visual perception for mobile users. Quality of experience (QoE) is an important perceptual visual metric. In this paper, we propose a user-centric QoE assessment model by joint considering technological-aware and psychology-aware parameters in the QoE communication ecosystem. For technological parameters, video encoding features are extracted from the video stream, and video content feature is estimated by video analysis. Moreover, user interests are also quantitatively collected as psychology parameters. Then, QoE model is developed by using support vector machine (SVM). Subjective tests have been performed. The collected data from subjective tests are used for training and validation of the proposed model. The experiment results show that the proposed user-centric QoE assessment model performs better in terms of high Pearson correlation coefficient (PCC) and low root-mean-square error (RMSE) compared with the conventional models.

A cosmid metagenomic library containing 1.3 × 105 clones was created from a soil sample. A novel gene (fae-xuan) encoding a feruloyl esterase was identified through functional screening. Primary sequence analysis showed that the gene consisted of 759 base pairs and encoded a protein of 252 amino acids. The gene was expressed in Escherichia coli BL21 (DE3) and the corresponding purified recombinant enzyme exhibited a molecular weight of 29 kDa. The FAE-Xuan showed high activity (40.0 U/mg) toward methyl ferulate with an optimal temperature and pH of 30 °C and 5.0, respectively. Besides methyl ferulate, FAE-Xuan can also hydrolyze methyl sinapate and methyl p-coumarate. The substrate utilization preferences and phylogenetic analysis indicated that FAE-Xuan belongs to type A FAE. FAE-Xuan was quite stable over a broad pH range from 3.0 to 10.0. The activity reduced remarkably in presence of Cu2+. FAE-Xuan can enhance the quantity of ferulic acid from de-starched wheat bran in presence of xylanase. The work presented here highlighted the effectiveness of metagenomic strategy in identifying novel FAEs with diverse properties for potential use in industrial production.

Land application of animal manure, as an important agronomic practice, represents a potential route to disseminate antibiotic resistance genes (ARGs) into the soil environment. Previous studies have demonstrated that manure-derived ARGs and pathogenic organisms rapidly decline over time following manure application, however, the impacts of long-term and repeated application of animal manure on the diversity and abundance of soil ARGs remain less understood. Here, we investigated the diversity and abundance of ARGs in greenhouse soils with long-term dairy cattle and chicken manure (DM and CM) application, and the half-life of antibiotic resistant bacteria (ARB) isolated from manured soils in Taiyuan, China. Both DM and CM significantly improved the levels of residual antibiotics, the abundances of ARGs, intI1 and soil organic carbon and total nitrogen that there was strong link between them. The half-life of ARB was different, and the correlations of ARGs, intI1 and tnpA genetic elements extracted from ARB with culture times were different. The significantly positive link was between the population of resistance bacteria and the half-life. Our finding suggested that both the levels of antibiotics and the stability of ARGs will determine the diversity and abundance of ARGs in manured soils.

Two new citrinin derivatives, pencitrin (1) and pencitrinol (2), and a known compound citrinin (3), together with its two known dimers, penicitrinone A (4), penicitrinone E (5), were isolated from an endophytic fungus P. citrinum 46 derived from Salicornia herbacea Torr. by adding CuCl2 into fermentation medium. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configurations of 1, 4, and 5 were determined by comparison of quantum chemical time-dependent density functional theory (TDDFT) calculated and electronic circular dichroism (ECD) spectra. Compound 1 exhibited potent cytotoxic activities towards A549 human lung cancer cells and HepG2 human liver cancer cells with IC50 values of 23.73 ± 3.61 and 35.73 ± 2.15 μM, respectively, whereas compound 5 showed moderate cytotoxic activities towards A549 and HepG2 cancer cells with IC50 values of 40.47 ± 4.52 and 53.57 ± 3.24 μM, respectively. The results from the current research highlighted the effectiveness and usefulness of the pipeline to discover novel bioactive fungal secondary metabolites by modification of the culture media.

Polyacetylene glycosides, (6Z, 12E)-tetradecadiene-8,10-diyne-1-ol-3(R)-O-β-D-glucopyranoside (trivially named coreoside E) and (6Z, 12E)-tetradecadiene-8,10-diyne-1-ol-3(R)-O-β-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranoside (trivially named coreoside F), were isolated from buds of Coreopsis tinctoria Nutt., together with one known compound, coreoside B. Their chemical structures were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivities. Coreoside E exhibited high levels of antimicrobial activity against Staphylococcus aureus and Bacillus anthracis with minimum inhibitory concentrations of 27 ± 0.27 and 18 ± 0.40 μM, respectively, whereas coreoside F and coreoside B showed weak antimicrobial activity against S. aureus and B. anthracis.

Button mushroom slices were dehydrated using freeze drying (FD) or combined with microwave vacuum drying (FMVD), and the changes in volatile composition were investigated and compared by using headspace GC–MS and electronic nose (E-nose). The results showed that the content of C8 compounds decreased during FD/FMVD process, while more alkanes and heterocyclic compounds were generated in the latter drying periods. The content of original thermal volatile compounds in FMVD products were significantly lower compared to FD, and the same trent was observed on alkanes and heterocyclic compounds. Moreover, the volatile compounds of FMVD products were more similar with fresh ones according to cluster analysis, and the critical point of change of volatile compounds might be at the end of sublimation period. In addition, E-nose could clearly discriminate button mushroom samples subject to different drying periods, the result obtained by E-nose showed good identity compared with GC–MS.

The worldwide use of the phenylurea herbicide, isoproturon (IPU), has resulted in considerable concern about its environmental fate. Although many microbial metabolites of IPU are known and IPU-mineralizing bacteria have been isolated, the molecular mechanism of IPU catabolism has not been elucidated yet. In this study, complete genes that encode the conserved IPU catabolic pathway were revealed, based on comparative analysis of the genomes of three IPU-mineralizing sphingomonads and subsequent experimental validation. The complete genes included a novel hydrolase gene ddhA, which is responsible for the cleavage of the urea side chain of the IPU demethylated products; a distinct aniline dioxygenase gene cluster adoQTA1A2BR, which has a broad substrate range; and an inducible catechol meta-cleavage pathway gene cluster adoXEGKLIJC. Furthermore, the initial mono-N-demethylation genes pdmAB were further confirmed to be involved in the successive N-demethylation of the IPU mono-N-demethylated product. These IPU-catabolic genes were organized into four transcription units and distributed on three plasmids. They were flanked by multiple mobile genetic elements and highly conserved among IPU-mineralizing sphingomonads. The elucidation of the molecular mechanism of IPU catabolism will enhance our understanding of the microbial mineralization of IPU and provide insights into the evolutionary scenario of the conserved IPU-catabolic pathway.

In the optimisation design of hybrid cloud storage data in the cloud computing environment, it is required to perform heuristic scheduling to data and to improve the ability to send and receive cloud storage data, so a heuristic scheduling algorithm for hybrid storage data in the cloud computing environment based on correlation spectral density feature extraction is proposed. In this algorithm, a distributed structure data model of hybrid storage data in the cloud computing environment is built and adaptive link forwarding control is designed for big data in cloud storage space. Simulation results show that in heuristic scheduling of hybrid storage data in the cloud computing environment, this method can improve the data storage throughput performance and provide good balance of data storage and high fidelity.

Plipastatin, a cyclic lipopeptide, exhibits inhibitory activity against filamentous fungi and plays an important role in the prevention of plant diseases, and post-harvest preservation of fruits and vegetables. However, the application of plipastatin has been hampered by low yields in natural strains, while chemical synthesis is not feasible because of its complex chemical structure. In this study, a scarless genetic modification method was applied to construct a heterologous expression host (Bacillus subtilis 1A751 Δpps) by knocking out the natural plipastatin genes from B. subtilis strain 1A751. The core genes for plipastatin biosynthesis from B. amyloliquefaciens HYM12 were captured and assembled with sfp and degQ using transformation-associated recombination (TAR) cloning. The resultant gene cluster was introduced into B. subtilis 1A751 Δpps to generate strain B. subtilis 1A751 Δpps amyE::ppsA–E + sfp + degQ. Its fermentation products were analyzed and identified by high-performance liquid chromatography-electrospray ionization-mass spectrometry. The results showed that the gene cluster for plipastatin synthesis was expressed successfully. This is the first time three gene fragments with significantly different DNA sizes (38.4, 0.3 and 0.8 kb) have been assembled by the TAR technique, thus we simultaneously established a method to express recombined large fragments in B. subtilis.

An ultra-sensitive aptamer-based biosensor for the detection of staphylococcus aureus was established by adopting the nicking enzyme amplification reaction (NEAR) and the rolling circle amplification (RCA) technologies. Aptamer-probe (AP), containing an aptamer and a probe sequence, was developed to act as the recognition unit of the biosensor, which was specifically bound to S. aureus. The probe was released from AP and initiated into the subsequent DNA amplification reactions where S. aureus was present, converting the detection of S. aureus to the investigation of probe oligonucleotide. The RCA amplification products contained a G-quadruplex motif and formed a three dimensional structure in presence of hemin. The G4/hemin complex showed horseradish peroxidase (HRP)-mimic activity and catalyzed the chemiluminescence reaction of luminol mediated by H2O2. The results showed that the established biosensor could detect S. aureus specifically with a good linear correlation at 5–104 CFU/mL. The signal values based on NEAR-RCA two-step cycle were boosted acutely, much higher than that relied on one-cycle magnification. The limit of detection (LoD) was determined to be as low as 5 CFU/mL. The established aptasensor exhibited a good discrimination of living against dead S. aureus, and can be applied to detect S. aureus in the food industry.

The original version of this article unfortunately contained a mistake in the image and caption of Fig. 6. The corrected version of the image and caption is shown here.

The bound phenolic compounds in rice bran were released and extracted with ethyl acetate based on alkaline digestion. An investigation of the chemical constituents of EtOAc extract has led to the isolation of a new compound, para-hydroxy methyl benzoate glucoside (8), together with nine known compounds, cycloeucalenol cis-ferulate (1), cycloeucalenol trans-ferulate (2), trans-ferulic acid (3), trans-ferulic acid methyl ester (4), cis-ferulic acid (5), cis-ferulic acid methyl ester (6), methyl caffeate (7), vanillic aldehyde (9) and para-hydroxy benzaldehyde (10). The structures of these compounds were determined using a combination of spectroscopic methods and chemical analysis. Among the compounds isolated, compound 3, 5 and 7 exhibited strong DPPH and ABTS(+) radical scavenging activities, followed by compounds 4 and 6. Compound 1 and 2 showed potent DPPH and ABTS(+) radical scavenging activities, compound 8 displayed moderate antioxidant activity against ABTS(+) radical, whereas compound 9 and 10 showed weak antioxidant activity.

A large amount of bound compounds, especially phenolics, present in corn bran has been underestimated because of difficulties in extracting them directly by organic solvents under mild conditions. Based on alkaline digestion, the bound compounds in corn bran were released and extracted with ethyl acetate. An investigation of the chemical constituents of the ethyl acetate (EtOAc) extract led to the isolation of ten compounds: trans-ferulic acid (1), trans-ferulic acid methyl ester (2), cis-ferulic acid (3), cis-ferulic acid methyl ester (4), vanillin (5), para-hydroxybenzaldehyde (6), 2-(1-oxo-2-hydroxyethyl) furan (7), graminones B (8), β-sitosterol glucoside (9), and sucrose (10). The chemical structures of these compounds were elucidated mainly by nuclear magnetic resonance and electrospray ionization mass spectrometry analysis. Graminones B was identified for the first time and showed potent angiotensin I-converting enzyme inhibitory activity, and compounds 1, 2, 3, and 4 displayed strong DPPH and ABTS+ radical-scavenging activity. This work represents the first recorded example of the isolation of compounds 3, 4, 8, and 9 from corn bran in the bound form.

Three new phenolic compounds, coretinphenol (1), coretincone (2), and coretinphencone (3), were isolated from the buds of Coreopsis tinctoria Nutt., together with nine known compounds, including butein (4), okanin (5), isoliquiritigenin (6), maritimetin (7), taxifolin (8), isookanin (9), marein (10), sachalinoside B (11), and 2-phenylethyl-β-d-glucoside (12). The chemical structures of these compounds were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivity. This work represents the first recorded example of the isolation of compounds 1–3, 6, 7, 9, 11, and 12 from C. tinctoria. Compounds 5–9 showed strong diphenyl(2,4,6-trinitrophenyl)iminoazanium (DPPH) radical-scavenging activity, with IC50 values of 3.35 ± 0.45, 9.6 ± 2.32, 4.12 ± 0.21, 6.2 ± 0.43, and 7.9 ± 0.53 μM, respectively. Compounds 2 and 8 exhibited angiotensin I-converting enzyme inhibitory activity, with IC50 values of 228 ± 4.47 and 145.67 ± 3.45 μM, respectively. The activities of phenolic compounds isolated from C. tinctoria support the medicinal use of this plant in the prevention of cardiovascular diseases.

Button mushroom slices were dehydrated using freeze drying (FD) or FD combined with microwave vacuum drying (FMVD), and the non-volatile component profiles were studied. The results showed that the level of non-volatile components in button mushroom firstly increased during sublimation of FD/FMVD process and then fell during desorption in FD process and MVD in FMVD process. Compared to FD products, the contents of soluble sugars and polyols in FMVD products were relatively low, whereas the contents of total free amino acids were significantly higher, close to the level of fresh mushroom. However, there was no significant difference in the contents of 5'-nucleotides and organic acids between FD and FMVD products. The equivalent umami concentration (EUC) values for FD and FMVD products did not differ from fresh, indicating that both drying methods could effectively preserve MSG (monosodium glutamate)-like components in button mushroom.

Food safety always remains a grand global challenge to human health, especially in developing countries. To solve food safety pertained problems, numerous strategies have been developed to detect biological and chemical contaminants in food. Among these approaches, nanomaterials-based biosensors provide opportunity to realize rapid, sensitive, efficient and portable detection, overcoming the restrictions and limitations of traditional methods such as complicated sample pretreatment, long detection time, and relying on expensive instruments and well-trained personnel. In this review article, we provide a cross-disciplinary perspective to review the progress of nanomaterials-based biosensors for the detection of food contaminants. The review article is organized by the category of food contaminants including pathogens/toxins, heavy metals, pesticides, veterinary drugs and illegal additives. In each category of food contaminant, the biosensing strategies are summarized including optical, colorimetric, fluorescent, electrochemical, and immune- biosensors; the relevant analytes, nanomaterials and biosensors are analyzed comprehensively. Future perspectives and challenges are also discussed briefly. We envision that our review could bridge the gap between the fields of food science and nanotechnology, providing implications for the scientists or engineers in both areas to collaborate and promote the development of nanomaterials-based biosensors for food safety detection.

An endophytic fungus Salicorn 19 was isolated from Salicornia bigelovii Torr. and identified as Fusarium tricinctum using a combination of translation elongation factor 1 alpha (EF-1α) and β-tubulin (β-TUB) gene sequence analysis. A bioassay-guided fractionation led to a new sesquiterpenoid ether with unique skeleton fusartricin (1), and two known compounds fusarielin B (2) and enniatin B (3) from the culture of Salicorn 19. Their chemical structures were elucidated based on ESI–MS and NMR analysis, as well as a comparison with the literature data. Antimicrobial experiments revealed that compounds 1 exhibited significant antimicrobial activities against E. aerogenes, M. tetragenu and C. albicans with the MIC values 19, 19 and 19 µM, respectively, and compound 2 showed a broader spectrum antimicrobial activity against M. smegmati, B. subtilis, M. phlei and E.coli with MIC values 19, 19, 10 and 10 µM, respectively, and compound 3 displayed powerful antimicrobial activities toward B. subtilis, E. aerogenes and M. tetragenus with MIC values 13, 13 and 6 µM.

Two new noroleanane-type triterpene saponins, Salbige A (1) and Salbige B (2), have been isolated from the aerial parts of Salicornia herbacea together with five other known compounds, including echinocystic acid (3), gypsogenin (4), pheophorbide a (5), (13(2)S)-hydroxy-pheophorbide a (6) and (13(2)S)-hydro-pheophorbide-lactone a (7). The chemical structures of these compounds were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivity. This work represents the first recorded example of the isolation of these compounds from S. herbacea. Compounds 1 and 2 exhibited potent antiproliferative activities and high levels of selectivity towards A549 cancer cells, with IC50 values of 52.35 and 79.39 μM, respectively, whereas compound 5 showed high levels of inhibitory activity against A549 and HepG2 cancer cells with IC50 values of 6.15 and 17.56 μM, respectively. None of these compounds exhibited antioxidant activities except for compound 7, which showed weak antioxidant activity.

An endophytic fungus Salicorn 8 was isolated from Salicornia bigelovii Torr. and identified as Fusarium equiseti based on internal transcribed spacer gene (ITS) sequence analysis. A new glucitol, diglucotol (1), together with five known compounds, cerebroside C (2), Nb-acetyltryptamine (3), 3β,5α,9α-trihydroxy-(22E,24R)-ergosta-7,22-dien-6-one (4), cerevisterol (5) and ergosterol peroxide (6), was isolated from the culture of Salicorn 8. The chemical structures of these compounds were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivities. This work describes for the first time the isolation of these compounds from F. equiseti. Compound 1 exhibited weak antiproliferative activities toward MCF-7, MDA-MB-231 and Caco-2 cancer cells with EC50 values of 97.56, 92.35 and 99.39 μM, respectively, whereas compound 5 showed high levels of inhibitory activities against MCF-7, MDA-MB-231 and Caco-2 cancer cells with EC50 values of 32.4, 41.5 and 37.56 μM, respectively. Compound 6 exhibited less potent inhibitory activities than 5 against MCF-7, MDA-MB-231 and Caco-2 cancer cells with EC50 values of 64.5, 52.4 and 77.56 μM, respectively. All of the other compounds were found to be inactive.

In this study, four common heavy metals, lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg) in rice and edible mushrooms of China were studied to evaluate contamination level and edible safety. Ninety two (92) rice samples were collected from the main rice growing regions in China, and 38 fresh and 21 dry edible mushroom samples were collected from typical markets in Nanjing City. The analyzed metal concentrations were significantly different between rice and edible mushroom samples (p

Tea polyphenols have strong antioxidant and antitumor activities. However, these health benefits are limited due to their poor in vivo stability and low bioavailability. Chitosan nanoparticles as delivery systems may provide an alternative approach for enhancing bioavailability of poorly absorbed drugs. In this study, tea polyphenol-loaded chitosan nanoparticles have been prepared using two different chitosan biomaterials, and their antitumor effects were evaluated in HepG2 cells, including cell cytotoxicity comparison, cell morphology analysis, cell apoptosis and cell cycle detection. The results indicated that the tea polyphenol-loaded chitosan nanoparticles showed a branch shape and heterogeneous distribution in prepared suspension. MTT assay suggested that tea polyphenol-loaded chitosan nanoparticles could inhibit the proliferation of HepG2 cells, and the cytotoxicity rates were increased gradually and appeared an obvious dose-dependent relationship. Transmission electron microscope images showed that the HepG2 cells treated with tea polyphenol-loaded chitosan nanoparticles exhibited some typical apoptotic features, such as microvilli disappearance, margination of nuclear chromatin, intracytoplasmic vacuoles and the mitochondrial swelling. In addition, the tea polyphenol-loaded chitosan nanoparticles had relatively weak inhibitory effects on HepG2 cancer cells compared with tea polyphenols. Tea polyphenols not only induced cancer cell apoptosis, but also promoted their necrosis. However, tea polyphenol-loaded chitosan nanoparticles exhibited their antitumor effects mainly through inducing cell apoptosis. Our results revealed that the inhibition effects of tea polyphenol-loaded chitosan nanoparticles on tumor cells probably depended on their controlled drug release and effective cell delivery. The chitosan nanoparticles themselves as the delivery carrier showed limited antitumor effects compared with their encapsulated drugs.

Salicorn 46, an endophytic fungus isolated from Salicornia herbacea Torr., was identified as Penicillium citrinum based on its internal transcribed spacer and ribosomal large-subunit DNA sequences using a type I polyketide synthase (PKS I) gene screening approach. A new polyketide, penicitriketo (1), and seven known compounds, including ergone (2), (3β,5α,8α,22E)-5,8-epidioxyergosta-6,9,22-trien-3-ol (3), (3β,5α,8α,22E)-5,8-epidioxyergosta-6,22-dien-3-ol (4), stigmasta-7,22-diene-3β,5α,6α-triol (5), 3β,5α-dihydroxy-(22E,24R)-ergosta-7,22-dien-6β-yl oleate (6), N b-acetyltryptamine (7), and 2-(1-oxo-2-hydroxyethyl) furan (8), were isolated from the culture of Salicorn 46, and their chemical structures were elucidated by spectroscopic analysis. Antioxidant experiments revealed that compound 1 possessed moderate DPPH radical scavenging activity with an IC50 value of 85.33 ± 1.61 μM. Antimicrobial assays revealed that compound 2 exhibited broad-spectrum antimicrobial activity against Candida albicans, Clostridium perfringens, Mycobacterium smegmatis, and Mycobacterium phlei with minimal inhibitory concentration (MIC) values of 25.5, 25.5, 18.5, and 51.0 μM, respectively. Compound 3 displayed potent antimicrobial activities against C. perfringens and Micrococcus tetragenus with a MIC value of 23.5 μM. Compounds 5 and 6 showed high levels of selectivity toward Bacillus subtilis and M. phlei with MIC values of 22.5 and 14.4 μM, respectively. The results of this study highlight the use of PCR-based techniques for the screening of new polyketides from endophytic fungi containing PKS I genes.

An endophytic oleaginous fungus Salicorn 5 has been isolated from Salicornia bigelovii Torr. and characterized as Cunninghamella sp. based on its morphological characteristics and ITS1-5.8S-ITS2 gene sequence analysis. The individual lipid compositions produced by Salicorn 5 were isolated and determined to be (1) oleic acid, (2) linoleic acid, (3) γ-linolenic acid (GLA), (4) 2,3-dihydroxypropyl oleate, (5) 2,3-dihydroxypropyl stearate, (6) 1,3-diolein, (7) 1,2-diolein, (8) 1,3-2-oleyl,2-stearoyl triacylglycerol, (9) ergosterol peroxide, (10) stigmasta-7,22-diene-3β,5α,6α-triol, (11) stigmasterol, and (12) ergosterol. The chemical structures of these compounds were determined by a combination of electrospray ionization mass spectrometry (ESI–MS) and nuclear magnetic resonance (NMR) analysis, as well as a comparison with data from the literature. Analysis of the fatty acids showed that they were composed predominantly of polyunsaturated fatty acids (PUFAs), including oleic acid (35.57 %), linoleic acid (21.58 %), palmitoleic acid (16.31 %), and linolenic acid (13.28 %), whereas stearic acid, palmitoleic acid, myristic acid, arachidic acid, and eicosenoic acid were found in lower amounts. These results could therefore provide a useful platform for fully exploring the potential application of oleaginous fungus Salicorn 5, and optimizing of the fermentation conditions for producing the PUFAs and high-value GLA, as well as providing further insight into the relationship between endophytes and their hosts.

Two new rubrolides, rubrolides R (1) and S (2), were isolated from the fermentation broth of the marine-derived fungus Aspergillus terreus OUCMDZ-1925. Their structures were elucidated on the basis of spectroscopic analysis and X-ray single crystal diffraction. Compound 1 showed comparable or superior antioxidation against 2,2'-azino-di(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals to those of trolox and ascorbic acid with an IC₅₀ value of 1.33 mM. Compound 2 showed comparable or superior anti-influenza A (H1N1) virus activity to that of ribavirin with an IC₅₀ value of 87.1 μM. Both compounds 1 and 2 showed weak cytotoxicity against the K562 cell line with IC₅₀ values of 12.8 and 10.9 μM, respectively.

An investigation of the chemical constituents of Salicornia herbacea has led to the isolation of one new natural product, pentadecyl ferulate (6), together with 11 known compounds, including phytol (1), stearolic acid (2), γ-linolenic acid (3), (3Z,6Z,9Z)-tricosa-3,6,9-triene (4), linoleic acid (5), stigmasterol (7), ergosterol (8), dioctyl phthalate (9), dibutyl phthalate (10), vanillic aldehyde (11), and scopoletin (12). The chemical structures of these materials were elucidated mainly by spectroscopic analysis. This work represents the first recorded example of the isolation of compounds 1, 2, 3, 4, 9, 10, and 11 from S. herbacea. The antioxidant experiments revealed that compound 6 possessed strong hydroxy radical and superoxide anion scavenging activities and was the principle antioxidant ingredient in the ethyl acetate extract. The antiproliferative results exhibited that compound 1 selectively inhibited HepG2 cells, whereas compounds 3 and 6 showed potent antiproliferative activities against HepG2 and A549 cells.