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La0.8Ce0.2Mn0.6Ni0.4O3 with (LCMN@CuO) and without (LCMN) CuO addition are prepared by solution methods, followed by reduction in 5% H2–N2 stream at 650 °C to form Ni exsolved and CuO reduced catalysts, LCMN@Ni and LCMN@Ni/Cu, for ethanol (EtOH) steam reforming (ESR). The catalysts are characterized by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), temperature programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy etc., and are evaluated for ESR with a steam/carbon ratio of 3 and a weight hourly space velocity (WHSV) of 4 h−1 at temperatures between 500 and 700 °C. Ni exsolution and CuO reduction are confirmed on the substrates in LCMN@Ni and LCMN@Ni/Cu. Both the catalysts demonstrate a complete conversion of EtOH, forming mainly H2, CO2, CO and CH4. And increasing temperature to 700 °C increases the yields of H2 and CO to the levels about 90% and 40%, respectively, at the cost of CH4; and such performance remains unchanged for 30 h. These results indicate that both LCMN@Ni and LCMN@Ni/Cu are promising catalysts for ESR, the main difference between them is that the latter is more chemically stable and more resistant to carbon deposition under ESR conditions.

Introduction The Epimedium herb, Yinyanghuo in Chinese, is a famous Chinese herbal medicine. In this study, an efficient extraction method was developed for the extraction of major bioactive constituent epimedin A, epimedin B, epimedin C and icariin from E. pubescens Maxim. using deep eutectic solvents (DESs). Methodology A series of choline chloride-based DESs were synthesised for the extraction of four target compounds. DES composed of lactic acid and choline chloride with the ratio of 2:1 was selected as the most promising. Three vital factors affecting the extraction yields including water content, volume of DES aqueous solution and extraction time were optimised systematically by Box-Behnken experimental design in combination with response surface methodology. A high-performance liquid chromatography ultraviolet (HPLC-UV) method was developed for the sensitive and accurate quantification. Results The optimal extraction conditions were obtained as follows: water content of 17.5% (v/v), volume of DES aqueous solution 3.14 ml, and extraction time of 21 min. Under the optimal extraction conditions, the developed DES method could supply almost the same extraction yield as 50% ethanol, which were 98%, 99%, 97%, 96% for epimedin A, epimedin B, epimedin C and icariin, respectively. Conclusion The present study exhibited high efficiency in extraction of prenylflavonol glycosides in E. pubescens Maxim. Thus, DESs could be used as an alternative for efficient extraction and quantification of biologically active components from natural medical plants.

Proanthocyanidins is flavan-3-ol polymers with many activities which attracted a lot of attention. However, most of the proanthocyanidins come from fruits and seeds, resulting in higher costs. The extraction of proanthocyanidins from leaves that were trimmed as wastes from fruit trees is of good economic benefits. The proanthocyanidins in persimmon leaves and loquat leaves were extracted and purified. The purity of persimmon and loquat leaves were 85.33 ± 0.11% and 88.45 ± 0.96% with yield of 3.40% and 2.37% respectively. Detailed structure information was analyzed. Persimmon leaves proanthocyanidins mainly consist of catechin with B-type link along with a small portion of gallocatechin, catechin gallate and A-type link. Loquat leaves proanthocyanidins consist of catechin, gallocatechin, gallocatechin gallate and afzelechin with B-type link along with a small portion of A-type link. The α-amylase inhibition effect of the two leaves was analyzed. Persimmon leaves proanthocyanidins and loquat leaves proanthocyanidins were two mixed-type inhibitors to α-amylase.

Although numerous in vitro studies have shown that osmolytes are capable of stabilizing proteins, their effect on protein folding in vivo has been less understood. In this work, we investigated the effect of osmolytes, including glycerol, sorbitol, betaine, and taurine, on the folding of a protein GB3 variant in E. coli cells using NMR spectroscopy. 400 mM osmolytes were added to E. coli cells; only glycerol stabilizes the folded protein, whereas betaine and taurine considerably destabilize the protein through modulating folding and unfolding rates. Further investigation indicates that betaine and taurine can enhance the quinary interaction between the protein and cellular environment and manifestly weaken the electrostatic attraction in protein salt bridges. The combination of the two factors causes destabilization of the protein in E. coli cells. These factors counteract the preferential exclusion mechanism that is adopted by osmolytes to stabilize proteins.

Objectives Alcohol dependence causes extensive damage to the central nervous system, resulting in impaired brain structure and behavioral changes. Moreover, histone deacetylase (HDAC) inhibitors restrain the activity of HDAC and cause increased histone acetylation, which may be related to alcohol dependence. Methods Ethanol dependence was modelled in animals by persistent alcohol exposure and tested in the conditioned place preference (CPP) paradigm. To induce CPP, the alcohol-treated rats were given orally gradient concentration (3%, 6%, and 9% v/v) alcohol administration for 20 consecutive days. The sodium butyrate (NaB)-treated rats were injected daily. Cognitive flexibility was evaluated using an attentional set-shifting task (ASST) in which the rats performed a series of seven consecutive discriminations after the final CPP paradigm. Results Ethanol administration induced alcohol dependence behaviors, with more time spent in the ethanol-paired compartment. Compared with the CPP scores of the control group, the scores of the ethanol- and NaB-treated groups were significantly higher. In the ASST, alcohol-treated rats had significantly increased number of trials to reach criteria (TTC) in most phases, higher error rate, and lower cognitive levels compared to the control group. Moreover, the present findings demonstrated that NaB combined with ethanol caused cognitive deficits as the result of an increased number of TTC during the ASST. Conclusions The attentional/cognitive flexibility of the prefrontal cortex of alcohol-dependent rats was damaged and the NaB administration procedure itself did not produce cognitive deficits, but instead exacerbated cognitive impairment in alcohol-dependent rats.

In this study, a covalent organic framework designated as TpPaNO2 was synthesized by a mechanochemical grinding method and then coated on stainless steel wire by a sol-gel technique to prepare a solid-phase microextraction fiber. The TpPaNO2 fiber based solid-phase microextraction coupled with gas chromatography-electron capture detection was applied to determine the residues of 11 pesticides (trlfuralln, dicofol, α-endosulfan, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethenyl]benzene, nitrofen, β-endosulfan, 1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethyl]benzene, 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane, bifenthrin, permethrin and fenvalerate) in vegetable and fruit samples. The effects of extraction time, extraction temperature, sample pH, stirring rate and desorption temperature on the extraction efficiency were investigated. Under the optimized conditions, the limits of detection for the eleven pesticides were in the range of 0.04-0.25 μg/kg. The recoveries of the eleven pesticides in the vegetable and fruit samples were 81.5-111% with the relative standard deviations less than 11.2%.

Directly modulating the choice between homologous recombination (HR) and non-homologous end joining (NHEJ) - two independent pathways for repairing DNA double-strand breaks (DSBs) - has the potential to improve the efficiency of gene targeting by CRISPR/Cas9. Here, we have developed a rapid and easy-to-score screening approach for identifying small molecules that affect the choice between the two DSB repair pathways. Using this tool, we identified a small molecule, farrerol, that promotes HR but does not affect NHEJ. Further mechanistic studies indicate that farrerol functions through stimulating the recruitment of RAD51 to DSB sites. Importantly, we demonstrated that farrerol effectively promotes precise targeted integration in human cells, mouse cells and mouse embryos at multiple genomic loci. In addition, treating cells with farrerol did not have any obvious negative effect on genomic stability. Moreover, farrerol significantly improved the knock-in efficiency in blastocysts, and the subsequently generated knock-in mice retained the capacity for germline transmission.

Chinese bayberry leaf proanthocyanidins (BLPs) are Epigallocatechin gallate (EGCG) oligomers or polymers, which have a lot of health-promoting activity. The activity is closely related to their behavior during in vitro digestion, which remains unknown and hinders further investigations. To clarify the changes of BLPs during gastrointestinal digestion, further research is required. For in vitro digestion, including gastric-intestinal digestion, colon fermentation was applied. Caco-2 monolayer transportation was also applied to investigate the behavior of different BLPs with different degrees of polymerization. The trimers and the tetramers were significantly decreased during in vitro gastric-intestinal digestion resulting in a significant increase in the content of dimers. The dimers and trimers were the main compounds utilized by gut microbiota and they were assumed not to degrade through cleavage of the inflavan bond. The monomers and dimers were able to transport through the Caco-2 monolayer at a rate of 10.45% and 6.4%, respectively.

A solid-phase microextraction with carbon nanospheres coated fiber coupled with gas chromatographic detection was established for the determination of eight polycyclic aromatic hydrocarbons (naphthalene, biphenyl, acenaphthene, fluorine, phenanthrene, anthracene, fluoranthene, and pyrene) in water and soil samples. The experimental parameters (extraction temperature, extraction time, stirring rate, headspace volume, salt content, and desorption temperature) which affect the extraction efficiency were studied. Under the optimized conditions, good linearity between the peak areas and the concentrations of the analytes was achieved in the concentration range of 0.5-300 ng/mL for water samples, and in the concentration range of 6.0-2700 ng/g for soil samples. The detection limits for the analytes were in the range of 0.12-0.45 ng/mL for water samples, and in the range of 1.53-2.70 ng/g for soil samples. The method recoveries of the polycyclic aromatic hydrocarbons for spiked water samples were 80.10-120.1% with relative standard deviations less than 13.9%. The method recoveries of the analytes for spiked soil samples were 80.40-119.6% with relative standard deviations less than 14.4%. The fiber was reused over 100 times without a significant loss of extraction efficiency.

A functionalized covalent organic framework (COF) was synthesized via room-temperature solvent-free mechano-chemical grinding method and used as a solid-phase extraction adsorbent for the extraction of eight biogenic amines (tryptamine, n-butylamine, phenylethylamine, cadaverine, putrescine, tyramine, spermine, and spermidine) in diverse meat samples. The target biogenic amines were derived with dansyl chloride to form stable fluorogenic derivatives for their high-performance liquid chromatography–fluorescence detection. The main important experimental parameters were investigated and optimized by both one-factor-at-a-time and response surface methodologies. Under the optimum conditions, a linear response for the biogenic amines was observed in the concentration range of 5.0–800.0 μg L−1 with the coefficients of determination (r2) ranging from 0.9944 to 0.9981. The limits of detection of this method (at a signal-to-noise ratio of 3) for the analytes ranged from 0.92 to 2.57 μg L−1. The method recoveries of the target biogenic amines for five meat samples ranged from 80.3 to 115%, with relative standard deviations lower than 12%. The results indicate that the prepared COF is an effective adsorbent for the enrichment of biogenic amines.

Lotus leaf flavonoids (LLF) are a group of bioactive natural substances. In this study, the structure, thermal properties, rheology behaviors and in vitro digestibility of cooked LLF-starch complex were investigated. Differential scanning calorimetry (DSC) analysis showed the shift in gelatinization peak to a higher temperature and the decrease in gelatinization enthalpies in the complexes significantly. The short-term retrogradation was retarded either. The flow behaviors of starch pastes changed with adding LLF. Scanning electron microscope (SEM) images showed a less compact structure in LLF-starch complex and laser confocal scanning microscope (CLSM) images detected that LLF mostly distributed around starch granules, which further prove the binding between LLF and starch. Moreover, fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) elucidated LLF probably interacted with starch by non-covalent bond especially hydrogen bond. In addition, LLF-starch complex exhibited inhibitory effect on starch digestion compared to pregelatinized starch, and the reasonable content of LLF-starch complex was (0.7 g/100 g). Thus, LLF-starch complex can be potentially used as a functional additive for high resistant starch (RS) and low glycemic index (GI) diets.

Multifunctional nanoplatforms for imaging‐guided synergistic antitumor treatment are highly desirable in biomedical applications. However, anticancer treatment is largely affected by the pre‐existing hypoxic tumor microenvironment (TME), which not only causes the resistance of the tumors to photodynamic therapy (PDT), but also promotes tumorigenesis and tumor progression. Here, a continuous O2 self‐enriched nanoplatform is constructed for multimodal imaging‐guided synergistic phototherapy based on octahedral gold nanoshells (GNSs), which are constructed by a more facile and straightforward one‐step method using platinum (Pt) nanozyme‐decorated metal–organic frameworks (MOF) as the inner template. The Pt‐decorated MOF@GNSs (PtMGs) are further functionalized with human serum albumin‐chelated gadolinium (HSA‐Gd, HGd) and loaded with indocyanine green (ICG) (ICG‐PtMGs@HGd) to achieve a synergistic PDT/PTT effect and fluorescence (FL)/multispectral optoacoustic tomography (MSOT)/X‐ray computed tomography (CT)/magnetic resonance (MR) imaging. The Pt‐decorated nanoplatform endows remarkable catalase‐like behavior and facilitates the continuous decomposition of the endogenous H2O2 into O2 to enhance the PDT effect under hypoxic TME. HSA modification enhances the biocompatibility and tumor‐targeting ability of the nanocomposites. This TME‐responsive and O2 self‐supplement nanoparticle holds great potential as a multifunctional theranostic nanoplatform for the multimodal imaging‐guided synergistic phototherapy of solid tumors., In this research, a tumor environment (TEM)‐responsive and continuous O2 self‐enriched drug delivery platform based on octahedral gold nanoshells (GNSs) using Pt‐decorated metal–organic frameworks (MOF) as inner template is constructed. The obtained nanostructures are further functionalized with human serum albumin‐gadolinium hybrid (HSA‐Gd, HGd) and loaded with indocyanine green (ICG) (ICG‐PtMGs@HGd) to achieve a multimodal imaging guided enhanced photodynamic therapy/photothermal therapy PDT/PTT effect.

Due to the misuse of hormones and antibiotics resulting in drug residues in meat products, serious concerns have arisen regarding to the potential risks for human health. In this paper, a simple and efficient method was developed to simultaneously quantify six steroid hormones and six antibiotics in fatty foods by combining pressurized liquid extraction (PLE) with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Adsorbents, extraction temperature, extraction time, recycle time and several other parameters were optimized in current investigation. The optimized PLE method was employed by using n-hexane-methanol-acetonitrile (2:1:1, v/v/v) as extraction solvent, silica gel as lipid sorbent, and the optimum parameters were 60 °C, 1500 psi and 10 min, respectively. Under the optimal conditions, the recoveries of spiked samples ranged from 82.2% to 115.0%. The limits of quantifications (LODs) were from 0.4 to 25.0 μg/kg. The developed PLE method was successfully applied to analyze steroid hormones and antibiotics in 27 fatty foods of hotpot ingredients without any additional clean-up steps. The results showed that the residues of estradiol benzoate (EB) and enrofloxacin (EN) in some matrices were much higher than maximum residue limits (MRLs) value, especially EB in fish, which exceeded 176.7 μg/kg. The results demonstrated that the developed method was sensitive and efficient in testing hotpot ingredients, and was an excellent analytical tool for monitoring residues of steroid hormones and antibiotics in fatty foods.

The inhibition effect of three common proanthocyanidins (PA) on the retrogradation properties of maize starch was investigated (including grape seed proanthocyanidins (GSPA), peanut skin proanthocyanidins (PSPA), and pine bark proanthocyanidins (PBPA)). Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis showed that PA could significantly decrease the values of melting enthalpy of retrogradation (ΔHr) and the degree of relative crystallinity, suggesting that the starch re-crystallization was retarded by PA. Scanning electron microscope (SEM) characterizations illustrated that retrograded PA-starch samples formed a looser matrix with less appearance of continuous flakes during storage. Overall, 0.5 %-2.0 % of three PAs exhibited suppression of starch retrogradation after 21-day cooling storage, mainly resulting from the PA-starch interaction. Among them, PSPA showed the most substantial inhibition effect on starch retrogradation, which might be attributed to its structural features. This study suggested that PA could be a new type of inhibitor to suppress starch retrogradation.

Small molecular gels (SMGs) have drawn much attention due to their unique properties which can be used in wide range of applications. In this work, the two-component hydrogels based on intermolecular interaction were prepared by the mixing appropriate ratios of melamine (M) and nitrilotriacetic acid (N) in pure water. These obtained hydrogels, which own a three-dimensional (3D) supramolecular structure, responded to several external stimuli such as temperature, pH and halogen ions. Otherwise, the two-component hydrogels mixed with M and N in organic-water mixtures were studied by calculating the Hansen Solubility Parameters of the solvents, a gelation range of the known two-component could be defined. The untested solvent lied in this known range might be gelled by M and N, which is a useful model to identify the gelation and the particular application of a suitable two-component hydrogels.

The aim of this paper is to summarise the blocking effects of parthenolide on the cytokines and pathways that cause inflammation. Analyses of the chemical structure of parthenolide have tried to identify the active domains that play key roles in its anti-inflammatory activity. This review focuses on the anti-inflammatory actions of parthenolide in both in vitro and in vivo. These data will be helpful for future investigations into the effects of parthenolide on inflammation.