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A catalyst-free strategy for regioselective hydroxydifluoroalkylation of alkenes with alkyl bromides was developed, affording a series of difluoroalkylated tertiary alcohols in moderate to good yields. This photocatalyst-free protocol shows broad substrate scope under mild conditions. Moreover, mechanistic studies revealed that a newly identified electron donor-acceptor complex is crucial to this transformation.

Polysaccharides were recovered from red grape pomace by hot water extraction and then subjected to deproteinization, decolorization, fractionization, and characterization. The extraction process conferred a crude polysaccharide yield of 8.45 % (w/w) and the highest decolorization rate of 63.12 % was obtained by soaking the crude polysaccharide solution with 0.20 g/mL HPD-300 macroporous resin for 3 h. Separation with the anionic DEAE Fast Flow column generated four fractions, which were negatively charged according to zeta potential measurement. All the fractions contained uronic acid and their weight-average molecular weights were within the range 2 × 106–4 × 106 Dal. The most abundant fraction GPP-3 was composed of arabinose, xylose, mannose, glucose, and galactose in molar ratio 8.05:1.37:2.85:1.30:7.81 and rhamnose was also present according to FTIR and NMR analysis. AFM observation revealed that aggregation occurred in GPP-3, while the Congo red and β-elimination tests indicated the existence of triple helix and -O- linkage in the fraction. Hence, red grape pomace is a potential source of water-soluble polysaccharides and their bioactivity needs further study.

Reported herein is a visible-light-induced sulfonation of α-trifluoromethylstyrenes with sodium sulfinates, which provides a series of α-trifluoromethyl-β-sulfonyl tertiary alcohols. This new synthetic protocol is enabled by a charge-transfer complex between oxygen and sulfinates, featuring broad substrate scope and scalability. Excellent functional group compatibility and chemoselectivity render this method suitable for sulfonation of pharmaceutically relevant molecules. In the presence of D2O, deuteriotrifluorinated products were also obtained, further demonstrating the flexibility and synthetic potentials of this strategy.

A copper(I)-catalyzed asymmetric alkylation of HPAr1Ar2 with alkyl halides is uncovered, which provides an array of P-stereogenic phosphines in generally high yield and enantioselectivity. The electrophilic alkyl halides enjoy a broad substrate scope, including allyl bromides, propargyl bromide, benzyl bromides, and alkyl iodides. Moreover, 11 unsymmetrical diarylphosphines (HPAr1Ar2) serve as competent pronucleophiles. The present methodology is also successfully applied to catalytic asymmetric double and triple alkylation, and the corresponding products were obtained in moderate diastereo- and excellent enantioselectivities. Some 31P NMR experiments indicate that bulky HPPhMes exhibits weak competitively coordinating ability to the Cu(I)-bisphosphine complex, and thus the presence of stoichiometric HPAr1Ar2 does not affect the enantioselectivity significantly. Therefore, the high enantioselectivity in this reaction is attributed to the high performance of the unique Cu(I)-(R,RP)-TANIAPHOS complex in asymmetric induction. Finally, one monophosphine and two bisphosphines prepared by the present reaction are employed as efficient chiral ligands to afford three structurally diversified Cu(I) complexes, which demonstrates the synthetic utility of the present methodology.

Carboxymethyl konjac glucomannan (CMKGM) is an anionic derivative of konjac glucomannan (KGM). Its coacervation with ovalbumin (OVA) was investigated through turbidity and coacervate yield measurem...

An organocatalyzed enantiodivergent synthesis of a multifunctionalized spirooxindole-norcamphor scaffold via a [4 + 2]-annulation between cyclicα, β-unsaturated ketone and methylene indolinones has been established. The presence of CaCl2 in DMF could reverse the enantioselectivity to facilely deliver the enantiomers of the corresponding spirooxindoles. Both enantiomers of the corresponding spirooxindoles were obtained in excellent yield and diastereo-/enantioselectivity by employing one single prolinosulfonamide catalyst.

An unprecedented electrochemical heterodifunctionalization of α-CF3 alkenes with benzenesulfonyl hydrazides was accomplished in this work, wherein a β-sulfonyl and a α-hydroxyl group were simultaneously incorporated across the olefinic double bond in a single operation. Consequently, a series of potentially medicinally valuable and densely functionalized α-trifluoromethyl-β-sulfonyl tertiary alcohols were assembled under mild conditions. Electrochemically-driven oxidative 1,2-difunctionlization of electron-deficient alkenes well obviates the need for oxidizing reagents, thus rendering this protocol more eco-friendly.

A novel phosphine-catalysed, one-pot domino approach for the annulation of 2-formylphenyl alkynoates with activated methylene compounds to construct various cyclopentene-fused dihydrocoumarins is reported. This developed strategy provides a facile and efficient approach for the synthesis of structurally complex coumarins from inexpensive and readily available alkynoates.

In the current study, heterostructured Ag@AgCl@AgI nanotubes were synthesized via an anion-exchange reaction between Ag@AgCl nanotubes and I− anions. Moreover, their photocatalytic performance towards the decontamination of dye contaminants were examined. These prepared photocatalysts were accordingly characterized using high-resolution scanning electron microscopy (HR-SEM), XRPD, XPS, field-emission transmission electron microscopy (FE-TEM), and photoluminescence (PL) spectroscopy. The structural identification analyses confirmed that the photocatalysts had nanotubular morphology. Compared to polyhedral Ag@AgI nanocomposites, the amalgamation of I− ions into the Ag@AgCl framework extraordinarily improved the photocatalytic performance. The synthesized Ag@AgCl@AgI nanotubes can also be reused due to their high stability. Under visible-light irradiation, >91.8% of Rhodamine B (RhB) was degraded within 45 min using the catalyst AI–2 (Cl−/I− = 1:1). The radical trap experiments indicated that the photodegradation of RhB was driven by the participation of superoxide radical and the action of holes. Due to the surface plasmon resonance effect, the photocatalyst AI–2 demonstrated higher photocatalytic performance, enhanced surface area and photoelectron transfer, which is also ascribed to its unique heterostructured configuration.

Recently, two-dimensional transition metal dichalcogenides, particularly WS2, raised extensive interest due to its extraordinary physicochemical properties. With the merits of low costs and prominent properties such as high anisotropy and distinct crystal structure, WS2 is regarded as a competent substitute in the construction of next-generation environmentally benign energy storage and conversion devices. In this review, we begin with the fundamental studies of the structure, properties and preparation of WS2, followed by detailed discussions on the development of various WS2 and WS2-based composites for electrochemical energy storage and conversion applications. In the end, some prospective prospects and promising developments of WS2 in these fields are proposed.

1,2-Bisphosphines have been identified as one class of important and powerful chiral ligands in asymmetric catalysis with transition metals. Herein, a copper(I)-catalyzed asymmetric hydrophosphination of α,β-unsaturated phosphine sulfides was developed with the assistance of "soft-soft" interaction between copper(I)-catalyst and the phosphine sulfide moiety, which afforded 1,2-bisphosphine derivatives with diversified electronic nature and steric hindrance in high to excellent yields with high to excellent enantioselectivity. Moreover, the challenging catalytic asymmetric hydrophosphination/protonation reaction was achieved with excellent enantioselectivity. Strikingly, the dynamic kinetic resolution of racemic diarylphosphines was also successfully carried out with high to excellent diastereo- and enantioselectivities. Interestingly, the nucleophilic copper(I)-diphenylphosphide species was characterized by 31 P NMR spectrum and mass spectrum. At last, three products were transformed to chiral 1,2-bisphosphines, which were employed as ligands in Rh-catalyzed asymmetric hydrogenation of α-amino-α,β-unsaturated ester. The α-amino acid derivative was produced in high enantioselectivity, which demonstrated the utility of the present methodology.

The first photoredox-catalyzed defluoroborylation of polyfluoroarenes with NHC-BH3 has been facilely achieved at room temperature via a single-electron-transfer (SET)/radical addition pathway. This new strategy makes full use of the advantage of photoredox catalysis to generate the key boryl radical via direct activation of a B-H bond. Good functional group tolerance and high regioselectivity offer this protocol incomparable advantages in preparing a wide array of valuable polyfluoroarylboron compounds. Moreover, both computational and experimental studies were performed to illustrate the reaction mechanism.

Regiodivergent formal [5+2]- and [4+2]-annulation reactions of indole derivatives with 2-(2-alkynyl)aryl cyclopropane-1,1-diesters (ACPs) have been developed. A series of tetracyclic indole derivatives were delivered in a 77% average yield with excellent regioselectivities enabled by Au(I)/Sc(III) bimetallic relay catalysis. A gram-scale reaction and further transformation of the resulting tetracyclic indoles demonstrated the practical utility of this protocol. Moreover, the photophysical properties of the obtained multicyclic compounds were also investigated.

A photoinduced SET process enables the direct B-H bond activation of NHC-boranes. In contrast to common hydrogen atom transfer (HAT) strategies, this photoinduced reaction simply takes advantage of the beneficial redox potentials of NHC-boranes, thus obviating the need for extra radical initiators. The resulting NHC-boryl radical was used for the borylation of a wide range of α-trifluoromethylalkenes and alkenes with diverse electronic and structural features, providing facile access to highly functionalized borylated molecules. Labeling and photoquenching experiments provide insight into the mechanism of this photoinduced SET pathway.

Potato resistant starch (RS) was prepared by microwave-toughening treatment (MTT). This study investigated the beneficial effects of RS on high-fat diet (HFD)-induced hyperlipidemia in C57BL/6J mice by evaluating changes in the gut microbiota. The mice were fed low-fat diet with corn starch, HFD with corn starch, HFD with potato starch (HFP), or HFD with RS (HFR) for 6 weeks. The results showed that the HFR group had lower body weight and total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels compared with the HFP group. Moreover, the brown adipose tissue levels of uncoupling protein 1 (UCP-1), β3-adrenoceptor (β3-AR), peroxisome proliferator-activated receptor-γ (PPAR-γ), and PPAR-γ coactivator-1α (PGC-1α) were increased. Our results showed that RS supplementation increased the Bacteroidetes/Firmicutes ratio and the abundance of short-chain fatty acid-producing Allobaculum, Ruminococcus, and Blautia. Our data suggest that RS prepared by MTT may be used as a prebiotic agent to prevent gut dysbiosis and obesity-related chronic diseases, such as hyperlipidemia, and obesity.

Chromanone is a privileged structure with a wide range of unique biological activities. A phosphine-promoted, three-component domino sequence of salicylaldehyde with but-3-yn-2-one was well designed for the construction of the chromanone skeleton under mild conditions. As a consequence, a series of novel chromanone analogues bearing an all-carbon quaternary center were facilely assembled from commercially available starting materials with moderate to good yields, which hold promising applications in pharmacological studies. Mechanistic experiments were conducted to confirm the proposed mechanism.

By means of high-speed emulsification and ultrasonic dispersing, emamectin benzoate (EB)–sodium lignosulfonate (SL) nanoformulation (EBSLNf) with a particle size of 150–250 nm was developed by the ...

Vesicles have been attracting a great deal of interest because of their great potential for health food, medicine, and biotechnology applications. This study aimed to develop a new type of debranched starch (DBS) vesicle for loading and delivering active components. DBS with a low degree of polymerization (6.75) and good water solubility was modified with octenyl succinic anhydride (OSA) to obtain an amphiphilic polymer. Both the Fourier transform infrared spectroscopy and the 1H nuclear magnetic resonance results confirmed the successful synthesis of amphiphilic OSA-DBS polymers. The OSA-DBS spontaneously formed 10–30 nm vesicles in a water system, as measured by transmission electron microscopy. The vesicles were relatively stable at different temperatures, pH values, and ionic strengths. Insulin was used as a hydrophilic functional ingredient model. The insulin-loaded vesicles exhibited a high loading content (∼13.36%). These OSA-DBS vesicles have potential utility as advanced carriers in the health food and biomedical industries.

Lysozyme was recovered from its aqueous solution by coprecipitation with sodium alginate. Electrostatic interaction between the two polyelectrolytes could occur between pH 2.0–9.0 and peaked at pH 3.0. The maximum lysozyme recovery of 97.10% was recorded at a mass ratio to sodium alginate of 2:1 and the presence of excessive sodium alginate reduced lysozyme precipitation. Complexation at pH 3.0 conferred the most compact and elastic network structure for the complex, but reduced the thermal stability and caused the greatest structural variation to lysozyme. The complexes separated at pH 4.5 and 6.0 could be dissolved by 1.0 mol/L NaCl, but that at pH 3.0 released only 77% lysozyme and further increase of NaCl concentration could not promote lysozyme liberation. It was concluded that coprecipitation with sodium alginate was potential in recovering lysozyme from its aqueous solutions and the dissociation of resultant complexes should be further enhanced to increase yield.

Debranched starches (DBSs) are widely used in food, pharmaceuticals, and health products. The purpose of this study is to separate fractions of debranched normal starch with different degrees of polymerization (DP). Five fractions were obtained by the ethanol precipitation fractionation method with different water-to-ethanol ratios, including a very long DBSp (p: precipitate), long DBSp1.5 (p1.5: water/ethanol = 1:1.5 precipitate), moderately long DBSp4 (p4: water/ethanol = 1:4 precipitate), short DBSs1.5 (s1.5: water/ethanol = 1:1.5 supernatant), and very short DBSs4 (s4: water/ethanol = 1:4 supernatant). The main peak DP values of different fractions of debranched normal corn starch were 24.41, 16.74, 13.70, 7.77, and 6.09, respectively. The fractions of DBSs from potato and sweet potato starches had larger molecular weights. The crystalline structure of DBSp and DPSp4 was B-type while that of DBSp1.5 was A-type. DBSs with different properties could be obtained from normal starch by the green and simple aqueous ethanol precipitation method.

A one-pot squaramide-catalyzed enantioselective ring-reorganization domino sequence (Michael addition/intramolecular ring-opening/lactamization) of 3-hydroxyoxindole and methyleneindolinone, which can be readily derived from 3-oxindole, has been established in this work. As a result, novel polycyclic quinolinone-spirooxindoles bearing three contiguous chiral centers were efficiently and step-economically assembled under mild conditions in high yields (up to 97%) with excellent enantioselectivities (up to >99% ee) and moderate to good diastereoselectivities (up to >95:5 dr).

Curcumin was entrapped in multilayered emulsions to increase its stability and bioavailability. Curcumin emulsion stabilized by whey protein isolate (WPI) was coated with chitosan (CHI) or carboxymethyl konjac glucomannan (CMKGM) alone to form secondary emulsions and their combination in sequence to form the tertiary emulsion, in which, the polyelectrolyte concentrations were 1.0% WPI for the primary emulsion, 0.4% CMKGM for the secondary emulsion -CMKGM, 0.2% CHI for the secondary emulsion -CHI, and 0.1% CMKGM for the tertiary emulsion. The characteristics of the emulsions, including their particle size, ζ potential, microstructure, creaming stability, and biopolymer distribution, were investigated and their colon-targeted delivery potential was evaluated through both in vitro and in vivo studies as well. The curcumin-loaded secondary and tertiary emulsions were stable with a narrow size distribution and were generated by layer-by-layer assembly according to confocal laser scanning microscope observation. When CMKGM was located at the outermost layer, the corresponding secondary and tertiary emulsions showed a greatly reduced release of curcumin in the simulated gastric fluid, but exhibited increased release in the β-mannanase-containing simulated colonic fluid. In vivo evaluation in mice demonstrated that the bioavailability of curcumin in the CMKGM-coated secondary and tertiary emulsions was increased by about 4 folds compared with that of free curcumin and curcumin could be released in a sustainable manner. These results demonstrated that multilayered emulsions coated with CMKGM could promote curcumin absorption in the gastrointestinal tract and hence is a promising colon-targeted delivery system for curcumin.

A palladium-catalyzed ring-opening oxo-formal [3 + 2]-cycloaddition reaction of novel donor-acceptor spirovinylcyclopropyl oxindole with 3-oxindole is described. The developed protocol provides facile access to oxo-bispirooxindole derivatives in good yields (up to 82% yield) with excellent diastereoselectivities (up to 20:1 dr).

A novel palladium-catalysed ring-opening [3 + 2]-annulation of spirovinylcyclopropyl oxindole with α,β-unsaturated nitroalkenes is reported. A series of spirooxindole derivatives were synthesized in high yields and good to excellent diastereoselectivities. This developed protocol offers a new and efficient pathway for the assembly of spirooxindoles.

The aim of this study was to evaluate the effect of white, red, green, yellow, blue and purple LED lights on visual and nutraceutical quality of broccoli florets during storage at 20 °C for 5 days. The results showed that purple LED light exhibited the best effect on reducing yellowing and retaining chlorophyll via down-regulating expression of genes related to chlorophyll degradation, including BoSGR, BoPAO, BoNYC1 and BoRCCR. On the other hand, yellow, blue and purple LED light increased contents of total phenolic and carotenoids compared to darkness. The highest glucoraphanin content was recorded in purple LED light treated broccoli florets, which was supported by the enhanced expression levels of genes related to glucoraphanin biosynthesis. Meanwhile, purple LED light promoted myrosinase activity and its expression, and reduced ESP expression; thus enhanced sulforaphane formation. In conclusion, among all LED lights, purple LED light showed a significant positive effect considering all estimated indicators and would be useful to maintain and improve the quality of broccoli during storage at 20 °C.

An l-pyroglutamic acid-derived bifunctional organocatalyst was designed and applied in an organocatalytic asymmetric direct aldol reaction between isatins and cyclohexanone, in which an erosion of enantiomeric excess of aldol adduct was unexpectedly observed. Through closely monitoring the reaction and performing extensive control experiments, it was determined that the erosion of ee was attributed to a rare stereospecific retro-aldol process. Moreover, effective manipulation of the retro-aldol process by tuning the use of starting materials was ultimately accomplished, leading to evidently upgraded enantioselectivity and functional group tolerance. This study demonstrates the impact of the hidden reaction pathway on the enantioselectivity in asymmetric transformation.

Two new 3D Zn(II)/Pb(II)-based MOFs, {[Zn9(mbpdc)7(3,3′-dmbpy)2 (μ3-OH)4]·(H2O)5}n (1), and {[Pb11(mbpdc)7(μ4-O)3(μ3-OH)2]·(H2O)}n (2) ((H2mbpdc = 2-methyl-4,4′-biphenyldicarboxylic acid, 3,3′-dmbpy = 3,3′-dimethyl-4,4′-bipyridine) have been synthesized and were structurally characterized. Complex 1 exhibits 3D network with 10-connected ile topology and is comprised of pentanuclear (Zn5N2O18) units bridged by mbpdc ligands and further pillared by 3,3′-dmbpy struts. Complex 2 is a new 3D lead(II) MOF constructed by dodecanuclear {Pb12(COO)16(μ3-OH)2(μ4-O)4} units and mbpdc ligands. Furthermore, the luminescence and the catalytic activities of 1–2 for the degradation of methyl orange in a Fenton-like process have also investigated.

Bovine serum albumin (BSA)-loaded microcapsules were prepared at pH 3.0, 4.5, and 6.0 through O-carboxymethyl (O-CMC) – gum Arabic (GA) coacervation followed by genipin crosslinking to explore the effects of coacervation acidity on the intestine-targeted delivery potency of resultant microcapsules. Confocal laser scanning microscope observation revealed that microcapsules with the multilayer structure were successfully prepared. As the coacervation pH rose from 3.0 to 6.0, the amount of O-CMC deposited on the microcapsule surface and the particle size increased accordingly. Swelling and BSA release results indicated that coacervation at higher pH conferred greater stability against simulated gastric fluid and better intestine-targeted delivery potency to the microcapsules. Circular dichroism analysis demonstrated that the structural integrity of entrapped BSA was well maintained during microencapsulation and incubation in simulated gastrointestinal fluids. Hence, genipin-crosslinked O-CMC – GA coacervates could be used to deliver nutraceuticals to the intestine and its delivery performance could be tailored by varying the coacervation pH.

The mixture of soybean protein isolate-emulsified vitamin E emulsion and chitosan was incubated at 50 °C, 70 °C, and 90 °C for 12 h to check whether Maillard reaction could occur between the two polyelectrolytes during coacervation and its effects on the properties of resultant microcapsules. Color measurements and FTIR analysis revealed that Maillard reaction occurred during microencapsulation and was favored by higher coacervation temperatures. Coacervation at the three temperatures effectively reduced the aggregation and significantly increased the particle size and zeta potential of the microcapsules. The microencapsulation performance was promoted in higher temperatures and coacervation at 90 °C led to a yield of 89.15% compared with 56.30% of the control. Besides, the Maillard reaction-modified microcapsules exhibited better flowability, higher bulk density, and greater stability. It is concluded that the coacervation temperature is an important processing parameter to control the morphology and properties of microcapsules prepared by protein – polysaccharide coacervation.

A facile and enantioselective access to a functionalized octahydroacridine scaffold was developed via an organocatalytic domino sequence between cyclohexenone and 2- N-substituted benzaldehyde. High levels of yields (up to 99%) and enantioselectivities (up to 99:1 er) were readily achieved in this developed organocatalytic transformation, which holds promising applications in the construction of complex multicyclic systems for further pharmacological studies.

Recently, AgX (X = Cl, Br, I) materials have been demonstrated as novel and efficient visible-light photocatalysts for the decomposition of various organic compounds and dyes. Herein, heterostructured Ag@AgCl@AgBr nanotubes were prepared by an anion-exchange reaction between Ag@AgCl nanotubes and Br− anions, and their photocatalytic activities towards the decomposition of organic pollutants were studied. The as-synthesized photocatalysts were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE–SEM), high-resolution transmission electron microscopy combined with energy-dispersive X-ray spectroscopy (HR–TEM/EDS), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The structure characterization studies confirmed that the photocatalysts had nanotubular morphology. Compared to polyhedral Ag@AgBr nanoparticles, the incorporation of Br− ions into the Ag@AgCl framework remarkably enhanced the photocatalytic activities. The as-prepared Ag@AgCl@AgBr nanotubes can also be reused due to their high stability. Under visible light irradiation, >98.5% of Rhodamine B (RhB) and 90.3% of Red Acid I (RAI) were decomposed within 45 min using the catalyst AB–2 (Cl−/Br- = 1:1). The catalyst AB–2 displayed higher photocatalytic activity due to its enhanced surface area and photoelectron transfer, attributed to its novel heterostructured configuration.

The conjugates of soybean protein isolate (SPI) with xylose and fructose were prepared via Maillard reaction by wet heating at mass ratio 4:1 and 80 °C for several hours. Absorbance at 420 nm indicated the existence of an induction period for the Maillard reaction between SPI and the two monosaccharaides and xylose was more reactive than fructose. SDS–PAGE and thermogravity analysis confirmed the occurrence of Maillard reaction. Fluorescence analysis revealed that the Maillard reaction led to relaxed structure for SPI in the conjugates. The conjugation with the two monosaccharaides significantly improved the solubility, but decreased the emulsifying activity of SPI. ζ-Potential measurement showed that the reaction changed the charge density of SPI and the specific effect depended on the sugar type and reaction degree. It is concluded that the wet heating-induced Maillard reaction with monosaccharaides might be a promising way for SPI modification due to shortened reaction time, improved solubility and tailored charge density.

Potato starch was treated by microwaving, toughening, and low-temperature aging to prepare resistant starch (RS). The functional properties of the resultant RS were evaluated and the effects of this microwave–toughening treatment (MTT) on the amylose content, RS content, digestive properties, pasting properties, morphological observation, crystal structure, and thermal performance of potato starch were determined. The optimal MTT parameters were microwaving at 300 W for 100 s, toughening at 55 °C for 16 h, and low-temperature aging at 4 °C for 18 h. After MTT, the amylose and RS contents of potato starch had increased from 26.08% and 11.54% to 35.06% and 27.09%, respectively. Furthermore, the pasting temperature increased from 66.8 °C to 76.36 °C, while the peak viscosity, trough viscosity, and final viscosity decreased significantly. After MTT, the potato starch surface had also changed significantly, and the crystallinity had increased from 32.43% to 51.36%. MTT starch had beneficial effects on fasting blood glucose, body weight, and organ index in mice. Furthermore, it had a protective effect on subcutaneous abdominal fat and liver tissue.

An efficient and diastereoselective decarboxylative oxa-1,3-dipolar cycloaddition between 3-oxindoles and diverse amino acids is developed to access novel oxazolidine-dispirooxindole skeletons bearing vicinal quaternary carbon centers. This protocol features operational simplicity, a broad substrate scope, and good to excellent chemical yields and diastereoselectivities. In particular, minimal solvent (1 mL/10 mmol) and chromatography-free purification render this synthetic process more efficient and environmentally benign in the context of green chemistry.

In the present study, the efficacy of PAW with different activation time and PAW treatment time in decontamination of Escherichia coli (E. coli) on broccoli sprouts and the effect of PAW on the quality of broccoli sprouts were investigated. The results showed that PAW60 treatment for 15 min resulted in the highest reduction of E. coli on broccoli sprouts. The bactericidal effect was also confirmed by the changes of morphology, cell membrane permeability and protein changes of E. coli cells via analyses of the scanning electron microscope (SEM), the flow cytometer and circular dichrograph. Meanwhile, no significant difference was observed in color, cellular structure and total phenolic content between PAW treatment and control. Moreover, PAW treatment did not affect or even enhanced sulforaphane formation in broccoli sprouts. These data indicate that PAW washing can be used a promising sterilization method to assure the food safety and quality of brcoccoli sprouts.

To improve morphological structure and stability of soy protein isolate - chitosan coacervate, a soy protein isolate-chitosan-sodium alginate ternary complex coacervate phase was successfully constructed by adding sodium alginate. The ζ -potential and turbidity data showed that soy protein isolate, sodium alginate, and chitosan interacted with each other in the pH range 5.0–7.0. The highest ternary coacervate yield was obtained at soy protein isolate/sodium alginate ratio 12:1 (g/g), soy protein isolate/sodium alginate:chitosan ratio 4:1 (g/g), pH 6.5, and total biopolymer concentration of 5 g/L. The viscoelastic properties and microstructure were also studied using rheology, fourier transform infrared spectroscopy, texture profile analysis, and scanning electron microscopy, which indicated that the ternary coacervates prepared in pH 5.5, 6.0, and 6.5 had a viscoelastic solid behavior (storage moduli between 12,600 and 35,000 Pa; loss moduli between 3440 and 10,000 Pa) with honeycomb porous network structures. The ternary coacervate prepared at pH 6.5 was more compact and clearly porous. The stability of the ternary complex coacervate phase to pH and ionic strength slight increased. The in situ cross-linking of sodium alginate can improve the structure properties of ternary coacervates, which may provide a new carrier to incoporate bioactive ingredients into food products.

The potential of the glutaraldehyde-crosslinked O-carboxymethyl chitosan (O-CMC)-gum Arabic (GA) coacervate as an intestine-targeted delivery system for hydrophobic compounds was concerned. OCMC-GA coacervates and emulsified bovine serum albumin (BSA)-loaded microcapsules were prepared in pH3.0, 4.5, and 6.0 and their swelling behaviors as well as BSA release profiles in simulated gastrointestinal fluids were measured. All the coacervates showed higher swelling ratios in the simulated gastric solution than in the simulated intestine and colon solutions and the values increased as the coacervation pH increased from 3.0 to 6.0, but a reversed trend was observed for the BSA release profile. SEM, TEM, and CLSM analysis revealed that the coacervation acidity influenced the swelling and BSA release behavior by changing the matrix density and O-CMC content of the coacervates. It was concluded that the O-CMC-GA coacervate could be used to deliver hydrophobic compounds to the intestine and its delivery performance could be tailored by selecting appropriate coacervation acidity and crosslinking degree.

The effects of coacervation acidity, phase separation temperature, ionic strength, and biopolymer ratio on the viscoelasticity of the N,O-carboxymethyl chitosan (NOCC) – gum Arabic (GA) coacervate were investigated by using coacervate yield as the indicator of electrostatic interaction strength. The strongest interaction between NOCC and GA occurred at pH 3.0, whereas the highest modulus values were found in the coacervate separated at pH 6.0. The coacervate yield did not vary with phase separation temperature in the range 4–55 °C, but the coacervate viscoelasticity declined as the temperature increased from 25 °C to 45 °C and then peaked at 55 °C. The presence of NaCl weakened the electrostatic interaction between the two polyelectrolytes, but no dose-dependent reduction in viscoelasticity was observed for their coacervates. Besides, the highest electrostatic interaction strength and coacervate viscoelasticity were recorded at different GA to NOCC ratios. It is proposed that the strength of electrostatic interaction is not the only parameter that determines the viscoelasticity of the NOCC – GA coacervate.

A novel synthetic protocol for the assembly of pyrrolo[1,2-a]indolenine has been developed through a highly diastereoselective [3+2] annulation of 1,1-cyclopropanediesters with indolenines in the presence of catalytic Yb(OTf)3. This new strategy allows a facile construction of the multicyclic system with the flexible variation on the substituents in high yields (up to 86%) with excellent diastereoselectivities (>20:1 dr) in most cases.

Glutaraldehyde-crosslinked O-carboxymethyl chitosan (O-CMC)–gum Arabic (GA) coacervates were characterized against coacervation acidity. As the coacervation pH increased from 3.0 to 6.0, the crosslinking degree of the coacervates and its sensitivity to glutaraldehyde concentration variation declined gradually, but the elasticity increased markedly. Crosslinking improved the structure compactness and thermal stability of the coacervates and high coacervation pH favored the increase of the two parameters, but a reverse trend was observed regarding swelling ratio in the simulated gastric fluid. It was concluded that glutaraldehyde-crosslinked O-CMC–GA coacervates with required properties could be tailored by selecting an appropriate complexation acidity.

STING (Stimulator of Interferon Genes) has become a focal point in immunology research and a target in drug discovery. The discovery of a potent human-STING agonist is expected to revolutionize current anti-virus or cancer immunotherapy. Inspired by the structure and function of murine STING-specific agonists (DMXAA and CMA), we rationally designed and synthesized four series of novel compounds for the enhancement of human sensitivity. In the cell-based assay, we identified six compounds from all the synthetic small molecules: 2g, 9g, and 12b are STING agonists that are efficacious across species, and all have the skeleton of acridone; 1b, 1c, and 12c just function in the murine STING pathway. Notably, 12b exhibits the best activity among the six agonists, and its inductions of both human and murine STING-dependent signalling are similar to that of 2′3′-cGAMP, which is a well-known STING inducer. While a protein assay indicated that 2 g, 9 g, and 12b could activate the pathway by directly binding human STING, 12b also displayed the strongest binding affinity. Additionally, our studies show that 12b can induce faster, more powerful, and more durable responses of assorted cytokines in a native system than 2′3′-cGAMP. Consequently, our team is the first to successfully modify murine STING agonists to obtain human sensitivity, and these results suggest that 12b is a potent direct-human-STING agonist. Additionally, the acridone analogues demonstrate tremendous potential in the treatment of tumours or viral infections.

The occurrence of Maillard reaction in protein – polysaccharide coacervated microcapsules and its effects on microcapsule properties were investigated. Vitamin E microcapsules were prepared by soybean protein isolate – chitosan coacervation at 50 °C, 70 °C, or 90 °C for 12 h in the presence of maltose. Chromatic and furosine measurements revealed that Maillard reaction occurred in the microcapsules and was favored by high incubation temperatures. The three coacervation temperatures did not destroy the microcapsule structure, but improved the microencapsulation efficiency and microencapsulation yield instead. The microcapsules exhibited decreased aggregation and the increased absolute zeta potential and particle size were believed contribute to this improvement. Stability analysis demonstrated that the microcapsules possessed enhanced resistance to dissolution in water and improved storage stability than control microcapsules. It is concluded that coacervation at a temperature high enough to initiate Maillard reaction is a promising way to improve the physiochemical properties of protein – polysaccharide coacervated microcapsules.

A general and straightforward protocol for di-/perfluoroalkylation of ortho-hydroxycinnamic esters via a photoredox-catalyzed cascade was developed to access a variety of 3-fluoroalkylated coumarins. This method was characterized by all-in-one synthetic design, simplified operation, mild reaction conditions, and broad substrate scope. Moreover, a sequential one-pot procedure starting from commercially available salicylaldehyde was also successfully realized to synthesize 3-fluoroalkylated coumarins.

A visible-light-induced difluoroalkylation of N,N'-cyclicazomethine imine was successfully realized through a novel photoredox radical-radical cross-coupling reaction. This developed protocol exhibits high functional group tolerance and affords a variety of difluorinated 3-pyrazolidinone scaffolds. Extensive mechanistic investigations have been undertaken, well revealing the involvement of a reductive radical-radical coupling pathway.

A new strategy for the synthesis of functionalized tetrahydrofuran derivatives was developed via a phosphine-catalysed [3 + 2] cyclization reaction of aromatic aldehydes with 4-phenylbut-3-yn-2-one. This is the first example of intermolecular cyclization of ynones with benzaldehydes, which essentially benefited from the intramolecular hydrogen bonding. This new protocol features a broad substrate scope, mild reaction conditions, operational simplicity and easy scale-up.

An asymmetric allylic alkylation-lactamization domino sequence of 3-aminooxindoles with Morita-Baylis-Hillman carbonates catalyzed by quinidine derivative (β-ICD) was developed. And a series of chiral spirocyclic oxindole-α-methylene-γ-lactams have been facilely prepared in good yields and stereoselectivities. This developed protocol would broaden the utilization of Morita-Baylis-Hillman carbonates in asymmetric construction of spirocyclic oxindoles.

A concise and facile approach for the construction of 2-hydroxy-2-substituted indol-3-ones was developed through an oxidative cyclization of 2-aminophenyl-1,3-dione. Using CAN and TEMPO as oxidants, C2-quaternary 2-hydroxy-indolin-3-ones were efficiently installed in moderate to excellent yields (up to 99%). Moreover, this developed protocol was further applied to synthetic studies towards natural product matemone by starting from readily available 2-amino-4-bromobenzoic acid, and the precursor for matemone was efficiently installed.

An intramolecular [3 + 2]-annulation of amide-linked donor-acceptor cyclopropane with in situ-generated imine is described. As a result, diverse hexahydropyrrolo[3,2-c]quinolinones, as the tricyclic core of martinellines, were efficiently assembled in good to excellent yield (up to 93%) with a good diastereomeric ratio (up to 98:2).