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Abnormal vasoconstriction, inflammation, and vascular remodeling can be promoted by angiotensin II (Ang II) in the renin-angiotensin system (RAS), leading to vascular dysfunction diseases such as hypertension and atherosclerosis. Researchers have recently focused on angiotensin I-converting enzyme inhibitory peptides (ACEIPs), that have desirable efficacy in vascular dysfunction therapy due to Ang II reduction by inhibiting ACE activity. Promising methods for the large-scale preparation of ACEIPs include selective enzymatic hydrolysis and microbial fermentation. Thus far, ACEIPs have been widely reported to be hydrolyzed from protein-rich sources, including animals, plants, and marine organisms, while many emerging microorganism-derived ACEIPs are theoretically biosynthesized through the nonribosomal peptide synthase (NRPS) pathway. Notably, vasodilatation, anti-inflammation, and vascular reconstruction reversal of ACEIPs are strongly correlated. However, the related molecular mechanisms underlying signal transduction regulation in vivo remain unclear. We provide a comprehensive update of the ACE-Ang II-G protein-coupled type 1 angiotensin receptor (AT1R) axis signaling and its functional significance for potential translation into therapeutic strategies, particularly targeting AT1R by ACEIPs, as well as specific related signaling pathways. Future studies are expected to verify the biosynthetic regulatory mechanism of ACEIPs via the NRPS pathway, the effect of gut microbiota metabolism on vascular dysfunction and rigorous studies of ACE-Ang II-AT1R signaling pathways mediated by ACEIPs in large animals and humans.

To achieve good indoor thermal comfortability in the hot summer days, searching for suitable solar shielding materials for buildings is of great importance. In this work, In doped CuS nanocrystals were first synthesized as novel NIR shielding materials for energy efficient windows. The influence of In doping on the microstructure, phase composition, optical performance, and thermal property of CuS were systematically explored. All the products adopted a hexagonal structure. Both of CuS and In doped CuS nanocrystals were composed of nanoplates and nanorods. All samples showed high visible transmittance (63.9–78.4%). Optical tests confirmed that the doping of indium ions was an effective way to improve the NIR shielding performance of the CuS films. The NIR shielding value of the films increased from 47.2% to 68.2% when the doping amount of In increased from 0 to 2%. The reason can be attributed to the enhanced NIR absorption induced by the increased hole concentration after doping of In3+ ions. Moreover, the In doped CuS films lowered the indoor temperature of the heat box by 8.4 °C in the thermal tests, further confirming the superior NIR shielding performance of In doped CuS nanocrystals.

Methane hydrate (MH) is potential new energy attracting attention from the scientific and industrial communities. In situ depressurization is considered a high energy efficient method. However, the...

3-Hydroxypropionic acid (3-HP) is an emerging platform chemical, which can be used for the production of various value-added chemicals. The traditional chemical synthesis of 3-HP has some difficulties in meeting the new sustainable development goals. Accordingly, microbial cell factories offer a green and sustainable method for the biosynthesis of 3-HP. Herein, a novel oxaloacetate pathway was successfully established for 3-HP biosynthesis. Firstly, a 3-HP production module was designed and constructed in Saccharomyces cerevisiae by overexpressing pyruvate carboxylase, benzoylformate decarboxylase, and 3-hydroxyisobutyrate dehydrogenase. Secondly, promoter engineering was used to optimize the glc7 expression, which could regulate the dephosphorylation of hexokinase to enhance the cytoplasmic energy metabolism, resulting in a 74.4% increase in 3-HP titer. Furthermore, a quorum-sensing system was applied to regulate the ptc7 expression, which could control the dephosphorylation of citrate synthase and mitochondrial hydroxylase to enhance the mitochondrial energy metabolism, resulting in a 98.0% increase in 3-HP titer. Finally, to further improve the 3-HP production, dynamic control of dephosphorylation was achieved to optimize the cytoplasmic and mitochondrial energy metabolism, resulting in a 4.2-fold increase in 3-HP titer in a 5 L bioreactor. The final engineered strain, thTAM-47, produced 18.1 g L−1 3-HP, which is the highest level of 3-HP production in S. cerevisiae to date. This work showed the shortest pathway for 3-HP production using glucose as a substrate in S. cerevisiae at present. Also, this is the first report on improving the pathway efficiency of 3-HP biosynthesis using a dephosphorylation regulation strategy to increase the intracellular ATP level.

Broken-rice starch nanoparticles with different mean particle diameters for 100, 200, 400 and 800 nm were prepared by nanoprecipitation, alkali freezing, cross-linking and H2SO4 hydrolysis methods respectively, and their structural, morphological and physicochemical properties were systematically characterized. The results showed that broken-rice starch nanoparticles had higher water absorption rate, and the maximum water absorption rate was obtained from the 100 nm starch granules being 91.53%, which means an increase about 2.07-fold in water absorption rate as compared with native rice starch. The stability of native rice starch is the worst, but the viscosity characteristic value is always higher than that of starch nanoparticles in the whole gelatinization process. The FT-IR spectrum showed that only starch nanoparticles prepared by cross-linking method showed the characteristic peak of secondary amide structure at 1714 cm−1, but the structure of was basically the same as native starch. The X-ray diffraction pattern revealed that there were obvious characteristic diffraction peaks near 2θ for 15°, 17°, 19° and 23° for the 800 nm starch nanoparticles and native rice starch, while the characteristic diffraction peaks of other starch nanoparticles disappeared in varying degrees due to the changed crystal structure.

Furan is a typical heterocyclic compound in pyrolytic tar and has a strong tendency of coke deposition in thermochemical conversion, leading to catalyst deactivation for tar upgrading. The present ...

Thermostable β-xylosidase produced by Aspergillus fumigatus (A. fumigatus) XC6 can be efficiently extracted and purified via an aqueous two-phase system consisting of 20% (m/v) PEG 2000 and 25% (m/v) NaH2PO4 with a purification factor of approximately 16. Maximum activity of the purified β-xylosidase was observed at 75 °C and pH 4.5 using p-nitrophenyl-β-Dxylopyranoside (pNPXyl) as a substrate. The thermal stability of purified β-xylosidase is higher than that of compared fungal strains. Thermotolerant kluyveromyces marxianus was directly added to a fermentation system composed of 50 g L−1 rice straw and 10 g L−1 (NH4)2SO4, but prehydrolysis with A. fumigatus XC6 pellets for 12 h yielded 11.2 g L−1 ethanol within 36 h, an amount 80% of the theoretical value. The results indicated that A. fumigatus XC6 β-xylosidase is a thermostable enzyme with high xylose production activity, and may have promising industrial application for cost-effective lignocellulosic bioethanol production.

Based on a β-cyclodextrin (β-CD) subject-object competition model, a simple and sensitive electrochemical aptamer sensor for the determination of tetracycline (TET) was fabricated. First, the TET aptamer modified with ferrocene (Fc) as a signal molecule was captured by β-CD loaded onto the gold electrode. Subsequently, TET was added to the detection system, causing a binding event between the target and aptamer with strong affinity during which process the aptamer configuration was changed from the original upright linear state to an agglomeration structure, resulting in its departure from the electrode surface. Consequently, an “off-signal” was turned along with the presence of the target. The results indicated that the TET concentration had a linear response to the signal ranging from 0.01 to 100 nM and the accurate detection limit could reach as low as 0.008 nM (3δ). The fabricated TET biosensor also showed outstanding detection specificity. Moreover, the suitability of the developed method was demonstrated in the determination of TET concentrations in different samples comprising water, milk, and bacteria culture medium, achieving acceptable recoveries for spiked samples ranging from 96.0 to 104.4%. This detection system was simple, economical, time-saving but remarkably sensitive, selective, and efficient, potentially rendering services in food safety screening and medical testing.

The upgrading of tar is a key issue for the sufficient application of biowaste pyrolysis technology. Molten salt, with high migration and diffusion of ions to prevent the deactivation of coke deposition of tar reforming functional metals, is considered as a feasible catalytic reaction medium and heat carrier for the upgrading of tar. The present study investigated the interactions between small molecular pyrolysis gases (including H2, CO, CH4) and main tar model compound in ternary carbonate eutectics (Li2CO3–Na2CO3–K2CO3). The results demonstrated that H2 could be decomposed to produce H radicals, promoting the conversion of toluene into gaseous products. CO32− could consume H radicals required by toluene cracking, making the process toluene polymerized to polycyclic aromatic hydrocarbons be strengthened. On the other hand, CO would react with OH radicals to produce H radicals and could enhance gas-generating process. In addition, toluene could react with CO to form benzaldehyde and phenylacetaldehyde. With the addition of CH4, more H radicals were supposed to be consumed, and toluene cracking process was further inhibited. Finally, the effect sequence of small molecular gases (H2 > CH4 > CO) on toluene reforming reaction was authenticated by investigating the impacts of introducing any two gases in toluene reforming.

Gastric cancer (GC) is one of the most commonly diagnosed malignancies in digestive tract and its underlying molecular mechanism is still not clear, so we aimed to reveal the relationship between GC and UDP-GlcNAc pyrophosphorylase-1 like 1 (UAP1L1). The detection of UAP1L1 expression in GC tumor and normal tissues was accomplished by immunohistochemistry and demonstrated the upregulation of UAP1L1 in GC, which was statistically associated with tumor grade. GC cell models constructed via transfection of UAP1L1-silencing/overexpressing lentiviruses were employed for evaluating the effects of UAP1L1 knockdown/overexpression on GC in vitro and in vivo. The results indicated that UAP1L1 played important role in development of GC through regulating cell proliferation, colony formation, cell apoptosis and cell migration. Subsequently, CDK6 was identified as a potential target in UAP1L1 induced regulation of GC, downregulation of which exhibited similar inhibition effects on GC with UAP1L1. Moreover, it was demonstrated that the promotion of GC by UAP1L1 overexpression could be significantly attenuated or even reversed by simultaneously silencing CDK6. In conclusion, UAP1L1 was reported to be a tumor promotor in the development and progression of GC which may exert its role through regulating CDK6 and may act as a candidate of therapeutic target in treatment.

Enzyme production as well as rice straw saccharification and fermentation were integrated to produce bioethanol in this study. Submerged fermentation of Na2CO3 pretreated rice straw to produce a complex enzyme for saccharification by Aspergillus fumigatus was performed. The major component of rice straw, that is cellulose, hemicellulose and lignin was almost completely degraded in 24 h. Using whole pretreated rice straw slurry as the substrate, the maximum concentrations of reducing sugar and ethanol were obtained with values of 63.6 g/L and 30.9 g/L, respectively, in a total hydrolysis and fermentation time at a substrate concentration of 8% (based on the original amount of rice straw). Fed-batch fermentation was employed for enzymolysis and fermentation of rice straw residue. Under a 32% total substrate concentration, 108.6 g/L ethanol was obtained in a total enzymolysis and fermentation time of 40 h. The results from different fermentation methods showed that the laccase produced by A. fumigatus in situ could effectively promote the enzymatic hydrolysis and fermentation through detoxifying the phenols produced during pretreatment and by the enzymatic hydrolysis processes.

Tung meal is the main byproduct generated during tung oil extraction from tung tree (Vernicia fordii) seeds and contains approximately 36–45 wt% crude protein. The disposal of large amounts of this resource has attracted increasing attention in relation to its value-added utilization. In this study, a new strain Pseudomonas aeruginosa LYT-4, was isolated for the bioconversion of tung meal into free amino acid fertilizer. Solid-state fermentation analysis showed that the protease activity of P. aeruginosa LYT-4 treatment was significantly higher than that under natural treatment throughout the fermentation period. The total percentage of free amino acids increased from 46.5% under natural fermentation to 55.5% under P. aeruginosa LYT-4 treatment. Pot experiments revealed that P. aeruginosa LYT-4 fermented-tung meal efficiently promoted spinach growth by increasing biomass and was more effective than both naturally fermented tung meal and chemical fertilizer. Furthermore, P. aeruginosa LYT-4 exhibited efficient in vitro antagonistic activity against three plant pathogens, Colletotrichum lini, Rhizoctonia solani and Fusarium oxysporum, possibly due to the abundant secondary metabolite clusters in its genome based on genomic analysis. In conclusion, P. aeruginosa LYT-4 exhibited a promising prospect for the industrial production of free amino acid fertilizer from tung meal with simultaneous potential biocontrol capacity.

Two new meroterpenoid compounds (1 and 2) together with five known meroterpenoid derivatives (3-7) were isolated from solid culture of mushroom Panus lecomtei. The structures of new compounds were confirmed by the analysis of NMR and HR-ESI-MS spectroscopic data. The biosynthetic pathway of 1-7 was postulated. All isolated compounds were evaluated for antibacterial activities against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Bacillus Calmette-Guerin. Compound 3 exhibited weak antibacterial activity against Bacillus Calmette-Guerin with the inhibition rate of 83.6% at 100 μmol·L-1. Other compounds showed no antibacterial activities against all tested pathogens at 100 μmol·L-1.

Femtosecond lasers have been used in combustion diagnostics. Based on the characteristics of femtosecond laser filamentation, many diagnostic techniques have been developed. Here, we propose a method, based on femtosecond laser filamentation, for equivalence ratio measurements in CH4/air gases. By measuring the spatially resolved spectra of the femtosecond laser-induced filament, we found that the variation of the equivalence ratio in the flow field would affect the spatial distribution of the emission intensity of femtosecond laser-induced filament. On this basis, the equivalence ratio was calibrated by using the relative spatial positions of N2 (337 nm) and C2 (516.5 nm) signals in the filament. This method overcomes the interference of local air disturbance, having lower measurement uncertainty.

Background Lignin is a complex aromatic heteropolymer comprising 15–30% dry weight of the lignocellulose. The complex structural characteristic of lignin renders it difficult for value-added utilization. Exploring efficient lignin-degrading microorganisms and investigating their lignin-degradation mechanisms would be beneficial for promoting lignin valorization. In this study, a newly isolated white-rot basidiomycete, Trametes hirsuta X-13, with capacity to utilize alkaline lignin as the sole substrate was investigated. Results The analysis of the fermentation properties of T. hirsuta X-13 using alkaline lignin as the sole substrate, including the mycelial growth, activities of ligninolytic enzymes and the rates of lignin degradation and decolorization confirmed its great ligninolysis capacity. The maximum lignin degradation rate reached 39.8% after 11 days of T. hirsuta X-13 treatment, which was higher than that of reported fungi under the same condition. Fourier transform infrared spectrometry (FTIR), gas chromatography–mass spectrometry (GC–MS) scanning electron micrographs (SEM), two-dimensional heteronuclear single quantum coherence NMR analysis (2D-HSQC NMR) collaborated with pyrolysis gas chromatography–mass spectrometry (py-GC/MS) analyses proved that lignin structure was severely deconstructed along with amounts of monomer aromatics generated. Furthermore, according to those chemical analysis, in addition to canonical Cα–Cβ breakage, the cleavage of lignin interunit linkages of β–β might also occur by T. hirsuta X-13. Conclusions This study characterized a newly isolated white-rot basidiomycete T. hirsuta X-13 with impressive alkaline lignin degradation ability and provided mechanistic insight into its ligninolysis mechanism, which will be valuable for the development of lignin valorization strategies.

The local structural, electronic, optical, and electron paramagnetic resonance (EPR) properties are uniformly studied for Cu2+ -doped rutile (TiO2 ) crystals by using the density functional theory (DFT) calculations. The local cation-oxygen bond lengths and planar bond angle, band gap, Mulliken charge and overlapping population, density of state (DOS), and UV-Vis absorption spectra are calculated for pure and copper-doped rutile. The smaller overlapping population of Cu-O bonds in the doped system than Ti-O bonds in pure rutile reflects weaker orbital admixtures or covalency of the former. Compared with pure rutile, Cu2+ doping leads to significant redshift of the UV-Vis absorption band and the narrow impurity band in visible and near-infrared regions arising from the Cu2+ d-d transitions and narrowing of the band gap by about 0.636 eV, possibly suggesting enhancement of visible light activity. The Cu dopant induces a spin magnetic moment of 0.74 μB for the doped rutile. The calculated UV-Vis absorption spectra and spin Hamiltonian parameters for copper-doped rutile show reasonable agreement with the experimental data and some improvement related to the previous perturbation formula calculations. Present systematic studies would be helpful to understand the mechanisms of the enhancement in the optical and magnetic properties of this material with transition-metal (especially Cu2+ ) dopants.

Background Pretreatment is a critical step required for efficient conversion of woody biomass into biofuels and platform chemicals. Fungal pretreatment is regarded as one of the most promising technology for woody biomass conversion but remains challenging for industrial application. The exploration of potential fungus strain with high efficient delignification and less processing time for woody biomass pretreatment will be valuable for development of biorefinery industry. Here, a newly isolated white-rot basidiomycete Peniophora incarnate T-7 was employed for poplar wood pretreatment. Results The chemical component analysis showed that cellulose, hemicellulose and lignin from poplar wood declined by 16%, 48% and 70%, respectively, after 7 days submerged fermentation by P. incarnate T-7. Enzymatic saccharification analysis revealed that the maximum yields of glucose and xylose from 7 days of P. incarnate T-7 treated poplar wood reached 33.4% and 27.6%, respectively, both of which were enhanced by sevenfold relative to the untreated group. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-ray diffraction (XRD) and pyrolysis gas chromatography–mass spectrometry (Py-GC/MS) characterization confirmed that lignocellulosic structure of poplar wood was largely broken by P. incarnate T-7, including delignification and de-crystalline of cellulose. Meanwhile, lignin component of poplar wood was selectively degraded by P. incarnate T-7, and G-type unit of lignin was preferentially attacked by the strain. Furthermore, quantitative proteomic analysis revealed that a considerable amount of lignocellulolytic enzymes were detected in the secretory proteins of P. incarnate T-7, especially with high abundance of lignin-degrading enzymes and hemicellulases. Combination of quantitative proteomic with transcriptomic analysis results showed that most of those lignocellulolytic enzymes were highly upregulated on poplar wood substrate compared to glucose substrate. Conclusions This study showed that P. incarnate T-7 could selectively delignify poplar wood by submerged fermentation with short time of 7 days, which greatly improved its enzymatic saccharification efficiency. Our results suggested that P. incarnate T-7 might be a promising candidate for industrial woody biomass pretreatment.

Ganoderma lucidum (G. lucidum) has been widely used in Asia to treat hypertension, but the active substances responsible for its antihypertensive effects remain unclear. Using the well-established angiotensin I-converting enzyme (ACE) as a target, we identified three ACE inhibitory peptides (ACEIPs), Gln-Leu-Val-Pro (QLVP), Gln-Asp-Val-Leu (QDVL), and Gln-Leu-Asp-Leu (QLDL), which account for the antihypertensive activity of G. lucidum. Notably, QLVP worked in a mixed-type manner against ACE with an IC50 value of 127.9 μmol/L. Molecular dynamics simulation suggested that the potent charge energy of QLVP, which interacted with Gln242 and Lys472 of ACE via a hydrogen bond and a salt bridge, potentially contributed to ACE inhibitory activity. Moreover, QLVP markedly activated angiotensin I-mediated phosphorylation of endothelial nitric oxide synthase in human umbilical vein endothelial cells and partly reduced mRNA and protein expression of the vasoconstrictor factor endothelin-1. This is the first report of the antihypertensive activity of small ACEIPs originating from G. lucidum mycelia, paving the way for the possible application of these peptides as potent drug candidates for treating hypertension.

Recent progress has been made in adding exogenous vegetable oils in culture media to promote bioactive metabolite production in several medicinal mushrooms, but the mechanism is still unclear. In this study, we found that the vegetable oil coix seed oil (CSO) could induce the biosynthesis of triterpene acids (TAs) and also significantly increase cytoplasmic nitric oxide (NO) and hydrogen peroxide (H2O2) concentrations in the mycelium of Ganoderma lingzhi. The change in TA biosynthesis caused by CSO could be reversed by adding NO scavenger or H2O2 scavenger, and adding NO scavenger or H2O2 scavenger resulted in the reduction of the cytoplasmic H2O2 or NO concentration under CSO treatment, respectively. Moreover, adding NO scavenger or H2O2 scavenger reversed TA biosynthesis, which could be rescued by H2O2 or NO donor, respectively. Taken together, our study indicated that both NO and H2O2 were involved in the regulation of TA biosynthesis, and CSO-activated NO and H2O2 were interdependent but independently regulated the TA biosynthesis under CSO treatment in G. lingzhi.

To achieve efficient utilization of solar power for environmental remediation, search for suitable materials as efficient solar light driven photocatalysts is one of the most challenging missions. In this work, F-doped (NH₄)₀.₃₃WO₃ was first synthesized as a novel near-infrared (NIR) photocatalyst with enhanced photocatalytic activity. Compared to that of pure ammonium tungsten bronze, a blue shift of the NIR plasmon band and an enhanced NIR absorbance of F-doped (NH₄)₀.₃₃WO₃ could be observed. 83% of rhodamine B (RhB) was degraded by F-doped (NH₄)₀.₃₃WO₃ under NIR irradiation within 180 min. The NIR photodegradation rate of the optimal F-doped (NH₄)₀.₃₃WO₃ for RhB was 0.0102 min–¹, about 8.5 times as high as that of (NH₄)₀.₃₃WO₃. The enhanced NIR photocatalytic performance of F-doped (NH₄)₀.₃₃WO₃ can be attributed to the remarkable enhanced generation and separation of NIR localized surface plasmon resonance induced electron–hole pairs. Moreover, the F-doped (NH₄)₀.₃₃WO₃ nanorods could also degrade 36% of RhB and 93% of RhB when exposed to the UV light and visible light, respectively. This work develops a promising photocatalyst with a full solar light response for future cleanup of environmental pollutants.

Smartly coupling exonuclease-induced target recycling signal amplifications with β-cyclodextrin host-guest recognition, a novel “signal-on” aptamer sensor for sensitive determination of ochratoxin A (OTA) was proposed for the first time. Firstly, the formation of double-strand DNA (dsDNA) was occurred by hybridizing OTA aptamer with its complementary DNA (cDNA) and as the probe DNA the cDNA at its 3′ terminal was labeled with methylene blue (MB). Next, when OTA was present, the aptamer tended to form aptamer-OTA complex with conformation of G-quadruplex instead of aptamer-cDNA duplex, leading to thus the probe DNA separating from dsDNA complex. Then the RecJf exonuclease was added, demolishing partially G-quadruplex structure and releasing a certain number of OTA. Sequentially, those released OTA would continue to react with the rest of aptamer in dsDNA, drawn into development of a new round of G-quadruplex complex, where the target cycling was realized. Meanwhile, as a signal molecule, MB modified on cDNA was liberated along with the cDNA being digested into monoucleotides by RecJf exonuclease, capable of diffusing onto the electrode surface due to host-guest recognition with β-cyclodextrin, whereupon the signal was enriched and yielded. In this way, cycles of target with continuous output of signal indicators were undergone, in which the detection of target was in return fulfilled with signal amplification owing to the joint endeavor of exonuclease and β-cyclodextrin. Under the optimal conditions, the raising signal maintained a linear relation with the logarithm of the target concentrations ranging from 10 pg/mL to 10.0 ng/mL and the detection limit reached as low as 3 pg/mL. This brand-new strategy was simple and low-cost but satisfactory in terms of detection limit, range and sensitivity, in all possibility to be applied extensively for diverse targets detection by easily alternating the corresponding aptamers.

In China, there are a large number of coal mine gobs have been formed as a result of longwall mining processes. These mine gobs contain an enormous amount of methane storage spaces within the gob formations. The methane storage spaces as well as guide methane drainage via vertical boreholes require quantitative measurements. In this study, physical simulation experiments were conducted for the purpose of obtaining digital images of gobs at various working face advance distances. Then, a Matlab-based digital image processing and analysis program was developed to process the obtained high-definition images, extract the geometrical parameters, and calculate the areas of methane storage spaces within the gobs. The results showed that the heights of the methane storage spaces first increased, and then stabilized as the gob lengths increased. The area sizes of the gobs increased gradually with the lengths, while the methane storage space areas were observed to first increase steadily to a maximum, and then decrease sharply. The main methane storage spaces exhibited a decreasing trend stage as the gob lengths increased. Whereas, the secondary methane storage spaces showed the characteristics of increasing trends. These research findings provide a theoretical foundation for the accurate predictions of both the methane storage capacities and methane drainage efficiency of longwall mining gobs.

Background Angiotensin II (Ang II), an important component of the renin–angiotensin system (RAS), plays a critical role in the pathogenesis of cardiovascular disorders. In addition, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have been considered as a promising platform for studying personalized medicine for heart diseases. However, whether Ang II can induce the apoptosis of hiPSC-CMs is not known. Methods In this study, we treated hiPSC-CMs with different concentrations of Ang II [0 nM (vehicle as a control), 1 nM, 10 nM, 100 nM, 1 μM, 10 μM, 100 μM, and 1 mM] for various time periods (24 h, 48 h, 6 days, and 10 days) and analyzed the viability and apoptosis of hiPSC-CMs. Results We found that treatment with 1 mM Ang II for 10 days reduced the viability of hiPSC-CMs by 41% (p = 2.073E-08) and increased apoptosis by 2.74-fold, compared to the control group (p = 6.248E-12). MYOG, which encodes the muscle-specific transcription factor myogenin, was also identified as an apoptosis-suppressor gene in Ang II-treated hiPSC-CMs. Ectopic MYOG expression decreased the apoptosis and increased the viability of Ang II-treated hiPSC-CMs. Further analysis of the RNA sequencing (RNA-seq) data illustrated that myogenin ameliorated Ang II-induced apoptosis of hiPSC-CMs by downregulating the expression of proinflammatory genes. Conclusion Our findings suggest that Ang II induces the apoptosis of hiPSC-CMs and that myogenin attenuates Ang II-induced apoptosis.

Modern rice production systems need a reliable, easy-to-use, efficient, and environmentally-friendly method to determine plant nitrogen (N) status , predict grain yield, and optimize N management. We conducted field experiments to determine the influence of different N rates on Soil Plant Analysis Development (SPAD) readings of rice leaves. We also performed field validations to evaluate the grain yield and N use efficiency under recommended N rates. Our results showed that leaf SPAD readings increased as N rates increased. We applied the recommended N based on the relationships between the N rates and leaf SPAD readings at the tillering and booting stages. The recommended N decreased N rates and improved N use efficiency without sacrificing grain yield. When compared to farmer practices (FP), the recommended N rates of optimization (OPT) decreased by 5.8% and 10.0%, respectively. In comparison with FP, the N agronomic efficiency of OPT increased by 5.8 and 10.0% while the partial factor productivity of N increased by 6.0 and 14.2%, respectively. The SPAD meter may be a reliable tool to analyze the N in rice, estimate real-time N fertilization, and improve N use efficiency.

The condensation-collection and quantitative analysis of bio-oil limit its component investigation and utilization. In order to find a convenient method for the analysis of bio-oil, the present study conducted an attempt for bio-oil quantitative analysis with the addition of internal standards before pyrolysis. Based on their good thermal stability, phenethyl acetate and naphthalene were selected as standards in the study and experiments were carried out to compare the effects of two added modes (adding into the biowaste before pyrolysis or adding into bio-oil after pyrolysis) on the bio-oil analysis. The results showed that both phenethyl acetate and naphthalene were mainly volatilized under testing conditions, which could be transferred into the oil with the volatile matters during biowaste pyrolysis. Through the co-pyrolysis experiments of the internal standards with lignin and cellulose, almost no interactions were found between the internal standards and such components. Furthermore, adding these standards before pyrolysis hardly affected the properties of noncondensable gas and biochar from the used biowaste samples (tobacco and sawdust waste). Compared with the bio-oil analysis results via traditional methods by adding standards into the bio-oil after pyrolysis, the results regarding the component distribution characteristics of the bio-oil were similar using the proposed method through the addition of standards before pyrolysis. Considering adequate mixing of the added standards (before pyrolysis) in the generated bio-oil, the proposed method could partly help to avoid inaccurate analysis of bio-oil components caused by incomplete collection of the pyrolytic volatiles.

Potassium (K) is among the essential macronutrients needed for plant growth and it’s also an extremely dynamic ion in both soil and plant systems. K+ moves intensely in a plant system but moderately in a soil system. The average soil deposits of K generally are plentiful, but their mainstreams are not readily available for crop uptake. Many researches have dealt with the response of crops to potassium application, but few literatures have tackled that of maize to available K and its uptake. This review seeks to discuss current progress concerning the relevance of K in maize crop production and its uptake; how this physiological action transforms into growth and yield. We have reviewed available studies on the content, roles of K in the soil-plant system and factors contributing to K uptake and transportation in plant. Also, the benefits of Potassium Solubilizing Microorganisms (KSMs) as an alternative or in combination with exchangeable K+ are reviewed. Furthermore, K deficiencies in maize causing constraint in physiological activities and rendering weak resistance to pests are also discussed. The current study indicates that intensive agricultural production has led to K nutrient limitation in organic or coarse-textured soil resulting in the reduction of available K reserves. However, an optimal application of K can prevent these fertilization imbalances, which will eventually increase soil fertility.

“Iron prawn” is a condition of severe growth retardation that fishers call. The giant river prawn (Macrobrachium rosenbergii) is a commercially important species contains high protein content and functional nutrients. However, no proteomic information is available for this species. We performed the shotgun 2DLC-MS/MS proteomic analysis of the total protein from “iron prawn”. Total 19,758 peptides corresponding to 2613 high-confidence proteins were identified. These proteins range in size from 40 to 70 kDa. KEGG analysis revealed that the largest group consisting total 102 KEGG pathway proteins comparing the “iron prawn” with the normal prawn. Additionally, 7, 11, 1, 6, and 5 commercially important enzymes were found in the eyestalk, liver, muscle, ovary, and testis, respectively. The functions of these differently expressed enzymes include immune system action against pathogens, muscle contraction, digestive system metabolism, cell differentiation, migration, and apoptosis in the severe growth retardation of “iron prawn”. Our work provides insight into the understanding of the formation mechanism of “iron prawn”.

The development of fungal fruiting bodies from a hyphal thallus is inducible under low temperature (cold stress). The molecular mechanism has been subject to surprisingly few studies. Analysis of gene expression level has become an important means to study gene function and its regulation mechanism. But identification of reference genes (RGs) stability under cold stress have not been reported in famous medicinal mushroom-forming fungi Cordyceps militaris. Herein, 12 candidate RGs had been systematically validated under cold stress in C. militaris. Three different algorithms, geNorm, NormFinder and BestKeeper were applied to evaluate the expression stability of the RGs. Our results showed that UBC and UBQ were the most stable RGs for cold treatments in short and long periods, respectively. 2 RGs (UBC and PP2A) and 3 RGs (UBQ, TUB and CYP) were the suitable RGs for cold treatments in short and long periods, respectively. Moreover, target genes, two-component-system histidine kinase genes, were selected to validate the most and least stable RGs under cold treatment, which indicated that use of unstable expressed genes as RGs leads to biased results. Our results provide a good starting point for accurate reverse transcriptase quantitative polymerase chain reaction normalization by using UBC and UBQ in C. militaris under cold stress and better support for understanding the mechanism of response to cold stress and fruiting body formation in C. militaris and other mushroom-forming fungi in future research.

Cell division can perturb the metabolic performance of industrial microbes. The C period of cell division starts from the initiation to the termination of DNA replication, whereas the D period is the bacterial division process. Here, we first shorten the C and D periods of E. coli by controlling the expression of the ribonucleotide reductase NrdAB and division proteins FtsZA through blue light and near-infrared light activation, respectively. It increases the specific surface area to 3.7 μm−1 and acetoin titer to 67.2 g·L−1. Next, we prolong the C and D periods of E. coli by regulating the expression of the ribonucleotide reductase NrdA and division protein inhibitor SulA through blue light activation-repression and near-infrared (NIR) light activation, respectively. It improves the cell volume to 52.6 μm3 and poly(lactate-co-3-hydroxybutyrate) titer to 14.31 g·L−1. Thus, the optogenetic-based cell division regulation strategy can improve the efficiency of microbial cell factories., Manipulation of genes controlling microbial shapes can affect bio-production. Here, the authors employ an optogenetic method to realize dynamic morphological engineering of E. coli replication and division and show the increased production of acetoin and poly(lactate-co-3-hydroxybutyrate).

BackgroundThe renin-angiotensin system (RAS) functions fundamentally to regulate the pathological process of cardiovascular diseases, such as heart failure and hypertension. As the major effector in RAS, angiotensin II activates angiotensin II receptors to initiate the downstream pathways, which lead to the phenotypes including apoptosis, hypertrophy, and cardiac remodeling. Human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) are being applied as a promising platform for personalized medicine to heart diseases. However, whether angiotensin II induces apoptosis in iPSC-CM is still obscure, which raises an uncertainty about the clinical applications of iPSC-CM.MethodsWe treated iPSC-CM with angiotensin II at eight concentrations (0 nM, 1 nM, 10 nM, 100 nM, 1 μM, 10 μM, 100 μM and 1 mM) and four incubation durations (24 hours, 48 hours, 6 days and 10 days), then PrestoBlue reagent and a apoptosis marker were used to examine the viability and apoptosis status of cardiomyocytes from each group. The expression levels of some apoptosis and proliferation related genes were also analyzed.ResultsHigh concentration angiotensin II with a long-term treatment caused apoptosis and cell viability drop-off in iPSC-CM. Specifically, under a 10-day treatment with 1 mM angiotensin II, the viability of iPSC-CM was reduced by an average of 41% (p=2.073E-08), and the percentage of apoptotic cells was 2.74 times higher than the controls averagely (p=6.248E-12). The data mining of previous RNA-seq data revealed that angiotensin II receptor type I was the major receptor in iPSC-CM. Conclusions: For the first time, our data confirmed the apoptotic effect of angiotensin II to iPSC-CM. The angiotensin II concentrations and exposure time for apoptosis induction were depicted in our study, which provided supports to iPSC-CM as an in vitro model for cardiovascular disease study.

The g-C3N4/MoS2 nanosheet heterojunction was prepared via a facile ball milling method. The microstructure and morphology of the composite were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), UV-vis diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectroscopy. The photocatalytic activities were evaluated by the degradation of organic Rhodamine B (RhB) under visible light irradiation. The results indicate that MoS2 nanosheets are successfully coupled into g-C3N4 to form a C3N4/MoS2 heterojunction. The kinetic constant of RhB degradation with g-C3N4/MoS2 nanosheets-2 wt% heterojunction (0.0368 min−1) is about 4.3 times as high as that of the bulk g-C3N4 (0.00840 min−1). The enhanced photocatalytic activities can be mainly ascribed to the efficient separation and transportation of photo-induced electron-hole pairs. The possible photocatalytic mechanism of composites was proposed according to the light trapping experiment.

The poly(triazine imide) (PTI) nanotube/ZnO heterojunction was prepared by two step method. PTI nanotube was synthesized from the condensation of melamine in a salt melt of LiCl–KCl. Then, nano-sized ZnO supported on PTI nanotube was prepared by a chemical precipitation method. The reduction rate of Cr(VI) under visible light irradiation was used to evaluate the activity of photocatalyst. It was found that the PTI/ZnO-1.5 wt% heterojunction exhibits the highest photocatalytic activity, which can reduce almost all Cr(VI) within 120 min. The kinetic constant of reduction reaction with PTI/ZnO-1.5 wt% heterojunction (0.0291 min− 1) is about 6 times as high as that of the PTI (0.00443 min− 1). A possible photocatalytic mechanism was discussed on the basis of the energy-band theory and scavenger experiments. Results show that photo-induced electrons participated in the reduction of Cr(VI) solution over the PTI/ZnO heterojunction. The enhanced photocatalytic activities of heterojunction can be attributed to efficient charge separation and good interfacial contact between PTI and ZnO.

The hydrate based technology process in porous media is an effective method for gas storage and separation. The formation of methane hydrate in SBA-15, an ordered mesoporous silicon material, was measured with tetrahydrofuran (THF) and tetra-n-butyl ammonium bromide (TBAB) aqueous solution at different pressure and temperature·THF and TBAB were selected to lower the equilibrium pressure at which the gas hydrates can efficiently formed. At the experimental condition of 1.8 MPa–2.0 MPa, SBA-15 was proved to be effective to methane uptake in the hydrates. The results showed that mesoporous silica can help to get the fast-kinetic formation of methane hydrates. The temperature was almost steady and only had two slight increase no more than 0.5 K. The pressure dropped rapidly and then became gentle, which translated into an increase in gas uptake rapidly in the beginning of 100 min and then maintained stable till the end. The reaction rate quickly reached the peak then rapidly dropped and slowly decayed. The desirable kinetics parameters of final gas uptake capacity, average of reaction rate and conversion of gas to hydrate (%) were obtained at higher pressure and lower temperature while THF was better than TBAB. A gas uptake capacity of 91.13 mmol methane gas per mole water was achieved when the hydrates were formed in the presence of THF with SBA-15.

Porous media can significantly promote the kinetics of hydrate formation by reducing the barrier of physical chemistry, where zeolites are typical microporous minerals. In this paper, the formation process and the reaction kinetics of the methane hydrate were investigated in A-type zeolite with tetrahydrofuran (THF) and tetra-n-butyl ammonium bromide (TBAB) aqueous solution in a long tubular reactor. The results showed that good kinetic characteristics of methane hydrate formation can be achieved with A-type zeolite. At initial pressure of 1.5 MPa and 1.8 MPa at 285.15 K, the aqueous solution of tetrahydrofuran (THF) and tetra-n-butyl ammonium bromide (TBAB) with 5A-type zeolite can form methane hydrate with gaseous methane in 10 h. The temperature raised significantly during the formation process of the system with 5A-type zeolite. Throughout the reaction, there was an obvious temperature rising region which was located in the inlet side of tubular reactor. The gas uptake increased rapidly in the beginning of 100 min and then maintained stable increasing during the hydrate formation. The final gas uptake capacity raised with the reaction pressure but was little affected by the type of promoter. From 1.5 MPa to 1.8 MPa the final gas uptake of hydrate increased 6.48% and 6.15% in the THF and TBAB solution respectively. The reaction rate quickly reached the peak after the reaction began and then rapidly dropped to decays. Simultaneously the average of reaction rate of THF solution was 13.2–30.8% higher than that of TBAB solution when the pressure was 1.5 MPa and 1.8 MPa at the same experimental conditions.

Novel TiO2/g-C3N4 hollow nanotube heterojunction was prepared via a molten salts method. The X-ray diffraction (XRD) result showed the crystalline phase of g-C3N4 hollow nanotube was changed from triazine-based g-C3N4 phase transition to heptazine-based g-C3N4 phase with the addition of TiO2 nanoparticles. The square hollow morphology, about 400 nm width and 60–70 nm wall thickness were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The UV-vis diffuse reflectance spectra (DRS) implied that the heterojunction can capture more visible light. The photoluminescence (PL) spectra showed that the heterojunction had efficient separation of photo generated electrons and holes. The heterojunction showed a rapid RhB degradation with the degradation rate of 95% in 60 min.

A new simple and highly sensitive electrochemical method for pyrophosphatase (PPase) activity detection was developed based on the peroxidase-like activity of G-quadruplex-Cu2+ DNAzyme. In the absence of PPase, Cu2+ could coordinate with pyrophosphate (PPi) to form Cu2+-PPi compound. While in the presence of PPase, it could destroy the coordinate compound because PPase catalyzed the hydrolysis of PPi into inorganic phosphate and produced free Cu2+, which then could be coupled with G-rich DNA to form G-quadruplex-Cu2+ DNAzyme. The formation of a mimic enzyme (G-quadruplex-Cu2+ DNAzyme) was immobilized on the surface of screen-printed gold electrode (SPGE). Using 3, 3', 5, 5'-tetramethylbenzidine (TMB) as a redox mediator and H2O2 as an enzyme substrate, the DNAzyme catalyzed the reduction of H2O2 to generate quantitative chronoamperometric signal. The catalytic activity of G-quadruplex-Cu2+ DNAzyme for TMB-H2O2 reaction was proportional to the activity of PPase, based on which, a simple and sensitive turn-on electrochemical method for PPase activity was thus developed for the first time. The chronoamperometric intensity of the system had a linear relationship with the PPase activities in the range of 1.0-50.0mU/mL and the detection limit could be down to 0.6mU/mL (S/N = 3). This proposed method was selective, cost-effective and convenient without any labels or complicated operations, which was furthermore applied to screen the inhibitor for PPase with high efficiency.

Based on the glass system of (71.5-x)SiO2-xAl2O3-11.5R2O-17RO (x = 0.5–6, mole fraction), the batch reaction process, structure and properties such as viscosity, strain point, annealing point, softening point and molten resistivity were studied by substituting the equal mole content of Al2O3 for SiO2. X-ray diffraction (XRD) analysis showed that the reaction of the glass batch was completed at about 1150 °C with all amorphous phase. Differential scanning calorimetry (DSC) test showed that the reaction process of the glass batch was basically the same, but with the increase of the content of Al2O3, the energy required for melting process increased. 27Al Nuclear Magnetic Resonance (NMR) results showed that in the glass network of the system, Al3+ ions basically existed in the form of 4-coordinated [AlO4] tetrahedra as the network formers. Raman spectra showed that the vibration of the glass network with non bridging oxygen decreased with the increase of the substitution amount of Al2O3 for SiO2, while the vibration of bridging oxygen increased gradually, which indicated that the compactness of the network was enhanced, and the vibration peak moved to the lower frequency region. The viscosity, resistivity, strain point, annealing point and softening point of the glass increased with the increasing content of Al2O3, and when the substitution was 4% mole fraction, the strain point could be as high as 550 °C which satisfied for the use of substrates for Copper Indium Gallium Selenium (CIGS) and Cadmium Telluride (CdTe) thin-film solar cells.

The defect structures and spin Hamiltonian parameters (SHPs) for V4+ in lead halo borate (xPbX2–(30 − x)PbO–68B2O3, X = F, Cl, Br and x = 5, 10, 15, 20 and 25 mol%) glass composites containing 2 mol% of V2O5 dopant are theoretically studied by applying the perturbation formulas of the SHPs for tetragonally compressed octahedral 3d1 clusters. The experimental SHPs are suitably reproduced by the optimal covalency factor N, relative tetragonal compression ratio ρ, core polarization constant κ and reduction factor H at various x, which are simulated with the corresponding Fourier type content functions. The distinct deviations of these quantities from the relevant simulated Fourier type content functions at 5 mol% of PbCl2 and PbBr2 are reasonably explained from the modifications of compactness and electronic cloud redistributions around V4+ at this content. This is supported by the previous analysis on the content variations of ionic conductivity of the systems.

A study on the fed-batch semi-simultaneous saccharification and fermentation (FB-S-SSF) of sodium carbonate-pretreated rice straw at biomass loads between 10.0 and 30.0% (m/v) was conducted. Three different feeding modes, i.e., enzyme feeding (E feeding), substrate feeding (SR feeding) and the combination of both E feeding and SR feeding as well as batch mode were conducted for comparison under identical biomass loads. High ethanol concentrations above 90 g/L were obtained in all modes at a biomass load ≥25.0%. The SR feeding modes achieved higher final ethanol concentrations than those of the E feeding mode and batch mode. At biomass loads of 25.0%, 116.8 ± 3.3 and 118.9 ± 3.6 g/L ethanol was obtained for the SR feeding mode and the combination of E feeding and SR feeding modes, respectively. For batch mode and E feeding mode, the ethanol concentrations were 112.3 ± 3.6 and 108.6 ± 3.0 g/L, respectively. The present study shows that the production cost of bioethanol from lignocellulose can be reduced by adopting in situ-produced crude enzymes produced by Aspergillus fumigatus combined with FB-S-SSF of sodium carbonate-pretreated rice straw at a high biomass load, which provides a new idea for effectively reducing the production cost of bioethanol from lignocellulose.

Polyaniline (PANI) doped with p-toluene sulfonic acid (PTSA) was synthesized by chemical oxidation method under the condition of conventional magnetic stirring (PTSA–PANI) and ultrasonic vibration (uPTSA–PANI) separately. Acrylic resin elastomer (ArE) was synthesized via radical polymerization. Novel all-organic dielectric elastomer composites (refer to the resultant composites herein as ArE/PTSA–PANI and ArE/uPTSA–PANI) were obtained by solution casting method. Chemical and microstructure characterization of the two kinds of resultant composites suggested that uPTSA–PANI possessed larger crystalline domain than that of PTSA–PANI and a unique branched structure. The dielectric properties of composites were measured in a wide frequency range, and the results demonstrated that both ArE/2.0% PTSA–PANI and ArE/2.0% uPTSA–PANI owned a high dielectric constant of more than 30 at 100 Hz, representing ten times increase with respect to neat ArE matrix (≈ 3). Moreover, it was found that ArE/2.0%uPTSA–PANI held better comprehensive dielectric properties at high frequency than that of ArE/2.0% PTSA–PANI composite; that was to say, ArE/2.0% uPTSA–PANI composite possessed not only high dielectric constant but also low dielectric loss. In addition, the thermogravimetric analysis indicated that the composite possessed better thermal stability than that of neat ArE. In addition, the elastic modulus of ArE/2.0% uPTSA–PANI composite was lower than 5 MPa.

In this paper, graphene oxide (GO) is integrated on commercial polypropylene separator by tape casting method and sandwiched between a sulfur cathode and the separator as a shuttle inhibitor of the Li-S battery. The issues of lithium polysulfides dissolution and shuttle effect are inhibited distinctly, and significant improvements not only in the active material utilization but also in capacity retention are observed. What's more, the improvement mechanism is studied in detail. The results demonstrate that the sulfur and polysulfide species in separator and electrolyte for the cell with GO-coating separator are much less than that with the pristine separator. The GO membrane still maintains three-dimensional porous and flexible structure with a few lithium polysulfides and Li2S2/Li2S nanoparticles anchored on the surface and inter-layers of GO sheets after long cycles. And the active materials are significantly localized within the cathode structure after GO-coating. In addition, less sulfate species, lithium salts, polysulfides and other insoluble species are identified on the cathode and separator after long-term cycling.

Triterpene acids are among the major bioactive constituents of lucidum. However, submerged fermentation techniques for isolating triterpene acids from G. lucidum have not been optimized for commercial use, and the antitumor activity of the mycelial triterpene acids needs to be further proven. The aim of this work was to optimize the conditions for G. lucidum culture with respect to triterpene acid production, scaling up the process, and examining the in vitro antitumor activity of mycelial triterpene acids. The key conditions (i.e., initial pH, fermentation temperature, and rotation speed) were optimized using response surface methodology, and the in vitro antitumor activity was evaluated using the MTT method. The optimum key fermentation conditions for triterpene acid production were pH 6.0; rotation speed, 161.9 rpm; and temperature, 30.1°C, resulting in a triterpene acid yield of 291.0 mg/L in the validation experiment in a 5-L stirred bioreactor; this yield represented a 70.8% increase in titer compared with the nonoptimized conditions. Furthermore, the optimized conditions were then successfully scaled up to a production scale of 200 L, and a triterpene productivity of 47.9 mg/L/day was achieved, which is, to our knowledge, the highest reported in the large-scale fermentation of G. lucidum. In addition, the mycelial triterpene acids were found to be cytotoxic to the SMMC-7721 and SW620 cell lines in vitro. Chemical analysis showed that the key active triterpene acid compounds, ganoderic acids T and Me, predominated in the extract, at 69.2 and 41.6 mg/g, respectively. Thus, this work develops a simple and feasible batch fermentation technique for the large-scale production of antitumor triterpene acids from G. lucidum.

Ganoderma lingzhi is a famous medicinal mushroom used as Chinese medicine or functional food and has been accepted across the globe. It is important to enhance the contents of bioactive compounds, which in turn improves the quality and biological activity of G. lingzhi fruiting body. In this work, freshly harvested G. lingzhi fruiting bodies were treated continuously with air or with 60 and 80% oxygen for 6 days. Samples were collected and determined initially and at 1 day interval during treatment. A high total ganoderic acid content of 29.44 g kg–1 was obtained in samples treated with 60% oxygen at day 3. Quantitative reverse transcriptase (qRT)-PCR and high-performance liquid chromatography (HPLC) analysis showed that the expression levels of hydroxymethylglutaryl-CoA synthase, squalene synthase, and oxidosqualene cyclase genes were substantially increased, resulting in the increase of ganoderic acids A, B, and C2 and ganoderenic acid B. The scavenging activities with 1,1-diphenyl-2-picrylhydrazyl radical, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical, hydroxyl radical, and superoxide radical and the DNA damage protective activity were also enhanced by high oxygen treatment. The results of this work provided a potential method to enhance the active metabolite synthesis in the fruiting body of G. lingzhi.

Crude glycerol is largely generated as the main by-product of the biodiesel industry and is unprofitable for industrial application without costly purification. The direct bioconversion of crude glycerol into 1,3-propanediol (1,3-PDO) by microorganisms is a promising alternative for effective and economic utilization. In this study, Klebsiella pneumoniae 2e was newly isolated for the conversion of crude glycerol into 1,3-PDO. Batch fermentation analysis confirmed that crude glycerol and its main impurities had slight impacts on the growth, key enzyme activity, and 1,3-PDO production of K. pneumoniae 2e. The 1,3-PDO yield from crude glycerol by K. pneumoniae 2e reached 0.64 mol 1,3-PDO/mol glycerol, which was higher than that by most reported 1,3-PDO-producing Klebsiella strains. Genomic profiling revealed that K. pneumoniae 2e possesses 30 genes involved in glycerol anaerobic metabolism and 1,3-PDO biosynthesis. Quantitative real-time PCR analysis of these genes showed that the majority of the genes encoding the key enzymes for glycerol metabolism and 1,3-PDO biosynthesis were significantly upregulated during culture in crude glycerol relative to that in pure glycerol. Further comparative genomic analysis revealed a novel glycerol uptake facilitator protein in K. pneumoniae 2e and a higher number of stress response proteins than in other Klebsiella strains. This work confirms the adaptability of a newly isolated 1,3-PDO-producing strain, K. pneumoniae 2e, to crude glycerol and provides insights into the molecular mechanisms involved in its crude glycerol tolerance, which is valuable for industrial 1,3-PDO production from crude glycerol. IMPORTANCE The rapid development of the biodiesel industry has led to tremendous crude glycerol generation. Due to the presence of complex impurities, crude glycerol has low value for industry without costly purification. Obtaining novel microorganisms capable of direct and efficient bioconversion of crude glycerol to value-added products has great economic potential for industrial application. In this work, we characterized a newly isolated strain, Klebsiella pneumoniae 2e, with the capacity to efficiently produce 1,3-propanediol (1,3-PDO) from crude glycerol and demonstrated its adaptation to crude glycerol. Our work provides insights into the molecular mechanisms of K. pneumoniae 2e adaptation to crude glycerol and the expression patterns of its genes involved in 1,3-PDO biosynthesis, which will contribute to the development of industrial 1,3-PDO production from crude glycerol.

Native and acetylated broken-rice starches (nanocrystals) with different degrees of substitution (DS) and their corresponding films were individually prepared, and the drug release profiles, weight loss, solubility and dispersion and surface morphology were comparatively studied. Bovine serum albumin (BSA) was used as a model drug. Acetylated native starch (ANS) DS 2.58, acetylated starch nanocrystals (ASN) DS 0.98, ASN DS 1.86, and ASN DS 2.72 were observed to be very soluble in chloroform. BSA was released rapidly from the native rice starch (NS) and ANS DS 2.58 films. ASN with high DS significantly slowed down the release of BSA from films, the percentages of BSA released from film ASN DS 2.72 only reached to 13% after 3.5 weeks release, and the release data followed Korsmeyer-Peppas equation. Further studies reveal that the particle size of ASN DS 2.72 was smallest, and the weight loss of ASN DS 2.72 film was lowest. The results demonstrate that acetylation and nanometer particle form of rice starch film can effectively retard protein drug release, and the prepared films based on ASN with high DS from broken rice may be suitable for the controlled protein delivery.

Methane hydrate (MH) has been considered as one of the cleanest energy resources. Its huge resource reserve and high energy density have attracted widespread attention in the scientific field. The dynamic behavior of MH formation and the resulting hydrate saturation are greatly influenced by the conditions of the formation process, such as water-gas ratio (WGR), pressure (P), temperature (T), and the mass fraction of NaCl (XNaCl). To gain a better understanding of the kinetic behavior of the in-situ MH deposits, a novel tri-axial horizon fixed bed reactor was set up to synthesize MH samples under typical marine conditions. A series of MH formation experiments were conducted under similar initial stress conditions (initial tri-axial stress of 16.50 MPa to simulate the overburden stress of marine MH) while perturbing the other key factors (WGR, P, T, and XNaCl) to investigate their effects. The results show that MH saturation attained at the end of formation from an initial water-gas mixing condition was negatively affected by initial WGR, T, and the existence of NaCl. MH formation in the fixed bed reactor increases initial XNaCl = 3.0 wt% to a maximum of XNaCl = 5.29 wt% and shifts the MH equilibrium curve to a more stringent condition for MH formation. Higher pressure promotes CH4 conversion to MH and increases MH saturation from the start of gas injection to the time when the pressure of the reactor was stable (ΔP

An ultra-performance liquid chromatography-electrospray ionization tandem triple quadrupole mass spectrometry (UPLC-ESI/MS/MS) method was developed for the detection of piperazine in chicken muscle. Following extraction and purification, the chicken muscle extract was injected into the UPLC system and analyzed. Piperazine detection was performed on a triple-quadrupole mass spectrometer with the ESI interface operating in positive mode. The most sensitive mass transition from the precursor ion to the product ion was 87.1 → 44.1 for piperazine. The coefficient (R 2) of piperazine was 0.9995 in the range of 1–200 μg/kg. The recovery and relative standard deviation (RSD) ranged from 102.93 to 111.46% and from 4.57 to 5.28% at 50.0, 100.0 and 200.0 μg/kg adding levels, respectively. Limits of detection (LODs) and limits of quantification (LOQs) were 0.4 and 1.0 μg/kg, respectively. This method was fully validated based on its specificity, sensitivity, linearity, precision, accuracy, matrix effect, and stability results. Compared to other researches, this new method not only omitted the derivative process, which simplify the pre-processing, but also proved a better sensitivity based on its low LOD and LOQ values.