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Density functional theory (DFT) calculation has been used to reveal palladium‐catalyzed mode of diaziridinone ring activation. Our theoretical studies found that oxidative addition of di‐tert‐butyldiaziridinone to Pd(II) can give a high valent Pd(IV) intermediate, along with the cleavage of N─N bond in di‐tert‐butyldiaziridinone through a concerted three‐membered‐cyclic transition state. Subsequent transformations via reductive elimination and β‐N elimination give the desired indolo[3,2‐b]indole product. The competitive activation modes such as metathesis and migratory insertion can be excluded in our selected model reaction. The rate‐determining step of this reaction is the oxidative addition of di‐tert‐butyldiaziridinone step. Distortion‐interaction analysis was conducted to reveal that the oxidative addition mode of di‐tert‐butyldiaziridinone is superior to the metathesis mode due to the lower interaction energy. [ABSTRACT FROM AUTHOR]

The stannum–ene reactions of both benzyne and cyclohexyne were realized, which is particularly suitable for cyclohexyne with a broad substrate scope and excellent chemoselectivity. Our DFT calculations via distortion/interaction analysis revealed that both stannum– and hydrogen–ene reactions with cyclohexyne have later transition states due to their higher distortion energies in the transition states than those in benzyne reactions, which lead to enhanced Pauli repulsion as the decisive factor in the interaction energy accompanied with enlarged energy gap between two types of ene reactions. Therefore, excellent chemoselectivity was disclosed in the cyclohexyne–ene reaction. [ABSTRACT FROM AUTHOR]

The stannum–ene reactions of both benzyne and cyclohexyne were realized, which is particularly suitable for cyclohexyne with a broad substrate scope and excellent chemoselectivity. Our DFT calculations via distortion/interaction analysis revealed that both stannum– and hydrogen–ene reactions with cyclohexyne have later transition states due to their higher distortion energies in the transition states than those in benzyne reactions, which lead to enhanced Pauli repulsion as the decisive factor in the interaction energy accompanied with enlarged energy gap between two types of ene reactions. Therefore, excellent chemoselectivity was disclosed in the cyclohexyne–ene reaction. [ABSTRACT FROM AUTHOR]

Summary: Basic analysis, electronic senses and HS‐SPME/GC‐MS were used to evaluate the effects of single and mixed cultures of Lactobacillus acidophilus‐26 and Lactobacillus plantarum‐56 on the quality of fermented red globe grape (RGG) juice. The results showed that mixed culture fermentation was superior to single strain fermentation in terms of viable bacteria counts, consumption of total sugar (TS), total soluble solids, pH, functionality, and antioxidant properties of RGG juice (RGGJ). Whereas the aroma profiles of developing juices were dominated by abundant esters, acids, alcohols, aldehydes, and ketones. Compared with the single inoculation, co‐inoculation of the two species induced lactic acid fermentations, leading to accumulation of acetic acid, ethyl acetate, and 2‐hexenol significantly. Moreover, higher concentrations of ethyl acetate, benzoic acid ethyl ester, octanoic acid, sorbic acid, 2‐phenylethanol, and 2‐hexenol represented the characteristic flavours of juices. To sum up, these findings suggested that L. acidophilus‐26 and L. plantarum‐56 could be used as fermented strains to ferment and improve the quality of RGGJ. [ABSTRACT FROM AUTHOR]

Purpose: To explore the feasibility of high-resolution MRI 3-dimensional (3D) CUBE T1-weighted magnetic resonance imaging (MRI) in combination with non-contrast-enhanced (NCE) magnetic resonance venography (MRV) for the assessment of lumen stenosis in May–Thurner syndrome. Methods: Twenty-nine patients underwent computed tomography venography (CTV) and high-resolution MRI-CUBE T1, and NCE MRV acquisitions. ANOVA and LSD tests were used to compare the stenosis rate and narrowest and distal diameters of the vessel lumen. Results: There were no significant differences in the estimated stenosis rate between CTV, CUBE T1, and NCE MRV (p = 0.768). However, there were significant differences in the measured stenosis diameters of the left common iliac vein (LCIV), with CTV giving the largest mean diameter and CUBE had the smallest mean diameter (p < 0.05). The measured normal LCIV diameters did not significantly differ between MRV and CUBE (p = 0.075) but were significantly larger on CTV than on MRV and CUBE (p < 0.05). Conclusions: Compared with CTV, a combination of CUBE and MRV could provide an improved assessment of the degree of lumen stenosis in May–Thurner syndrome and demonstrate acute thrombosis. MRI underestimates the diameter of the vessel in comparison with CTV. MRI can be a substitute tool for Duplex ultrasound and CTV. [ABSTRACT FROM AUTHOR]

Theoretical calculations were performed to investigate the mechanism and enantioselectivity of cinchonine–thiourea‐catalyzed intramolecular hetero‐Diels–Alder cycloaddition of ethynylphenol derivatives to afford axial chirality naphthalenylpyran products via a vinylidene ortho‐quinone methide (VQM) intermediate. The results show that this transformation occurs through a reaction pathway involving the deprotonation of the naphthol moiety by the quinuclidine base, intramolecular proton transfer in ammonium naphthalenolate, and [4+2] cycloaddition. It is found that the axial chirality of the VQM intermediate is generated by the protonation step, which affects the enantioselectivity of the reaction. The enantioselectivity for the generation of the VQM intermediate is controlled by steric repulsion with the cinchonine framework, which provides an R‐axial chirality VQM as the major intermediate. Moreover, the enantioselectivity for the axial chirality of the naphthopyran product is controlled by the cycloaddition step, in which an extra hydrogen bond between the naphthalenol and cinchonine moieties leads to a favorable configuration for the generation of the S‐axial chirality naphthopyran product. The calculated enantioselectivity and enantiomeric excesses coincide with experimental observations. [ABSTRACT FROM AUTHOR]

Graphical abstract Theoretical advances on the mechanistic study of Ag-catalyzed carbene/nitrene/silylene transfer reactions were summarized in this review, which could be considered to involve two major steps: Ag–carbene/nitrene/silylene complex formation and the subsequent transformation of these complexes. Highlights • DFT studies on the mechanism of Ag-catalyzed group transfer reactions are summarized. • The mechanism consists of Ag–carbene/nitrene/silylene formation and transformation. • The mechanism is related to the electronic behaviors of Ag–carbene/nitrene/silylene. Abstract Carbene and its isoelectronic species nitrene and silylene, have long been considered reactive intermediates in organic synthesis. Ag-catalyzed carbene/nitrene/silylene transfer reactions have emerged as an important topic because they have made remarkable progress in organic synthesis. A series of theoretical investigations on the mechanism of these reactions is important to ensure their thorough understanding and aid design of new synthetic methodologies. Here, a mechanistic overview of Ag-catalyzed carbene/nitrene/silylene transfer reactions is given, which can be separated into two major steps including Ag–carbene/nitrene/silylene complex formation and the subsequent transformation of these complexes. Theoretical studies revealed that Ag–carbene and Ag–silylene complexes can be considered as typical Fischer-type complexes, in which the carbene/silylene moiety behaves as both a sp σ donor and p π acceptor. Conversely, the triplet Ag–nitrene complexes are usually more stable than the singlet ones because of the higher electronegativity of nitrogen than those of carbon and silicon. Density functional theory calculations have indicated that the triplet state of an Ag–nitrene complex has two unpaired electrons that are mainly localized on nitrogen. In this review, theoretical studies on the generation of Ag–carbene/nitrene/silylene complexes are systematically summarized. Moreover, the nucleophilic functionalization of Ag–carbene/nitrene/silylene complexes with halogen, hydroxyl, carbonyl, alkane, or arene groups are also considered theoretically. We believe that the mechanistic details discussed here will be of great importance for rational design of desired catalytic cycles and reactions. [ABSTRACT FROM AUTHOR]

Wang, W.J. and Shan, C.H., 2020. Sustainable development of basin economy and marine economy. In: Bai, X. and Zhou, H. (eds.), Advances in Water Resources, Environmental Protection, and Sustainable Development. Journal of Coastal Research, Special Issue No. 115, pp. 602-605. Coconut Creek (Florida), ISSN 0749-0208. The coordinated development of basin economy and marine economy is not only necessary, but also has the objective basis of the coordinated development. This paper discusses the coordinated development of basin economy and ocean economy from the perspective of basin economy. Taking the basis and effect of basin ocean economic linkage development as well as the Yangtze River economic belt as an example, this paper analyzes and calculates the correlation degree. It is pointed out that the correlation between basin economy and marine economy with the correlation between marine tertiary industry and basin tertiary industry are very high. The correlation between marine main industry and basic basin secondary industry are relative high. Based on this, some suggestions are put forward to promote the coordinated development of basin ocean economy. [ABSTRACT FROM AUTHOR]

Wang, W.J. and Shan, C.H., 2020. Sustainable development of basin economy and marine economy. In: Bai, X. and Zhou, H. (eds.), Advances in Water Resources, Environmental Protection, and Sustainable Development. Journal of Coastal Research, Special Issue No. 115, pp. 602-605. Coconut Creek (Florida), ISSN 0749-0208. The coordinated development of basin economy and marine economy is not only necessary, but also has the objective basis of the coordinated development. This paper discusses the coordinated development of basin economy and ocean economy from the perspective of basin economy. Taking the basis and effect of basin ocean economic linkage development as well as the Yangtze River economic belt as an example, this paper analyzes and calculates the correlation degree. It is pointed out that the correlation between basin economy and marine economy with the correlation between marine tertiary industry and basin tertiary industry are very high. The correlation between marine main industry and basic basin secondary industry are relative high. Based on this, some suggestions are put forward to promote the coordinated development of basin ocean economy. [ABSTRACT FROM AUTHOR]

Ru-Catalyzed aromatic C–H bond activation and functionalization have emerged as important topics because they have resulted in remarkable progress in organic synthesis. Both experimental and theoretical studies of their mechanisms are important for the design of new synthetic methodologies. In this review, a mechanistic view of the Ru-mediated C–H bond cleavage step is first given to reveal the C–H bond activation modes, including oxidative addition, metathesis and base-assisted deprotonation. In this process, directing groups play an important role in determining the reactivity of the C–H bond. The C–H bond activation generally leads to the formation of a Ru–C bond, which is further functionalized in the subsequent steps. The mechanisms of Ru-catalyzed arylation, alkylation, and alkenylation of arenes are summarized, and these transformations can be categorized into cross-coupling with electrophiles or oxidative coupling with nucleophiles. In addition, the mechanism of ortho-ruthenation-enabled remote C–H bond functionalization is also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Organocatalysis has emerged as an effective strategy for chemical synthesis. Within this area, phosphine‐catalyzed coupling reactions have attracted considerable attention because of their versatility and wide range of applications in the construction of new C−C bonds. Recently, various experimental studies on the phosphine‐catalyzed coupling reaction of allenes have been reported, and mechanistic and computational studies have also progressed considerably. As a nucleophile, phosphine can react with an allene to form a zwitterionic phosphoniopropenide intermediate. After stepwise cycloaddition and proton transfer, the phosphine catalyst can be regenerated by C−P bond cleavage. Alternatively, the zwitterionic phosphoniopropenide intermediate could also be protonated by a Brønsted acid to generate a phosphonium intermediate, which can be used to construct new C−C bonds by electrophilic addition. In this review, we have summarized details of mechanistic studies of phosphine‐catalyzed allene coupling reactions that follow these two reaction modes. In addition to detailing the reaction pathway, the regioselectivity and diastereoselectivity of the phosphine‐catalyzed allene coupling reaction are also discussed in this review. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculation has been used to reveal the mechanism of Pd-catalyzed disilylation of carbene, which is a pathway to construct disilylmethane derivatives. The DFT calculations indicate that the reaction starts with carbenation of a Pd(0) catalyst. Oxidative addition of disilane can then generate a carbene-coordinated disilylpalladium intermediate. Carbene insertion into the Pd–Si bond followed by reductive elimination gives the disilylmethane product and regenerates the Pd(0) catalyst with the formation of two C–Si bonds. The rate-determining step of this reaction is the carbenation step. The computational results show that the phosphine ligand is unfavorable for this type of reaction because of its high dissociation energy. In this type of reaction, a smaller substrate is favorable for the oxidative addition step because the weaker steric repulsion leads to a lower activation free energy of the oxidative addition step. The computational results also reveal that the reactivity of digermane and distannane is higher than that of disilane, which can be attributed to their low bond dissociation energies. [ABSTRACT FROM AUTHOR]

The stannum–ene reactions of both benzyne and cyclohexyne were realized, which is particularly suitable for cyclohexyne with a broad substrate scope and excellent chemoselectivity. Our DFT calculations via distortion/interaction analysis revealed that both stannum– and hydrogen–ene reactions with cyclohexyne have later transition states due to their higher distortion energies in the transition states than those in benzyne reactions, which lead to enhanced Pauli repulsion as the decisive factor in the interaction energy accompanied with enlarged energy gap between two types of ene reactions. Therefore, excellent chemoselectivity was disclosed in the cyclohexyne–ene reaction. [ABSTRACT FROM AUTHOR]

Summary Jujubes are an excellent source of sugar and nutrients, making them well‐suited for fermentation. Previous research on jujubes has primarily focused on their use in fermented beverages and fruit wines, but their potential for vinegar production has not been sufficiently explored. Therefore, this study produced jujube vinegar from jujube as raw material using microbial fermentation technology, and the changes in bioactive substances and volatile components during different fermentation stages were monitored. Results revealed that the primary organic acids in jujube vinegar were acetic acid, malic acid and lactic acid. The levels of phenolic compounds, such as epicatechin and ferulic acid, increased significantly by 3.5‐fold and 3.2‐fold, respectively, after acetic fermentation, resulting in an improvement in antioxidant activity. In addition, a total of seventy‐three volatile substances were detected in jujube vinegar, with acids accounting for 72.13% of the overall content. Isoamyl alcohol, ethyl phenylacetate, benzaldehyde and 3‐hydroxy‐2‐butanone were also the principal flavour compounds of jujube vinegar, which are the main source of its intense flavour. This study reveals the dynamic law of nutrients and flavour compounds during the fermentation process of jujube vinegar. The findings provide a theoretical reference and practical basis for the production of jujube vinegar. [ABSTRACT FROM AUTHOR]

Both aryne 1,4‐disubstitution and 1,2,4‐trifunctionalization were accomplished from tertiary amines bearing a penta‐2,4‐dien‐1‐yl moiety. These transformations could directly incorporate a C−N and a C−C bond para to each other on an aryne intermediate via a sequential nucleophilic addition and [5,5]‐sigmatropic rearrangement. When arynes bearing 3‐tethered electrophiles were employed, a cascade regioselective nucleophilic addition, intramolecular cyclization, and remote diastereoselective [5,5]‐sigmatropic rearrangement process was observed. Our density functional theory (DFT) calculations revealed that hydrogen‐bonding interactions between two C−H hydrogens on the penta‐2,4‐dien‐1‐yl chain and the oxygen anion generated upon N‐nucleophilic annulation reaction in the [5,5]‐sigmatropic rearrangement step is responsible for the remote diastereoselective control in this reaction system. [ABSTRACT FROM AUTHOR]

Both aryne 1,4‐disubstitution and 1,2,4‐trifunctionalization were accomplished from tertiary amines bearing a penta‐2,4‐dien‐1‐yl moiety. These transformations could directly incorporate a C−N and a C−C bond para to each other on an aryne intermediate via a sequential nucleophilic addition and [5,5]‐sigmatropic rearrangement. When arynes bearing 3‐tethered electrophiles were employed, a cascade regioselective nucleophilic addition, intramolecular cyclization, and remote diastereoselective [5,5]‐sigmatropic rearrangement process was observed. Our density functional theory (DFT) calculations revealed that hydrogen‐bonding interactions between two C−H hydrogens on the penta‐2,4‐dien‐1‐yl chain and the oxygen anion generated upon N‐nucleophilic annulation reaction in the [5,5]‐sigmatropic rearrangement step is responsible for the remote diastereoselective control in this reaction system. [ABSTRACT FROM AUTHOR]

• Storage temperature altered the expression of genes in melon fruit. • 3 °C could result in a negative gene transcription for Hami melon sweetness flavor. • 0.5 °C promoted starch degradation by regulating the expression of AMY and BMY genes. Temperature control is an effective method to maintain the postharvest quality of fruit and extend their shelf life. However, quality deterioration, or more specifically, faded sweetness, occurs in long-term cold-stored melons. This study aimed to characterize the transcriptomic profiles of Gold Queen Hami melon using RNA sequencing at different storage temperatures (21 °C, 3 °C, and 0.5 °C). The results indicated that storage temperature significantly affected the expression of numerous genes in the melon fruit, especially several key genes involved in the starch and sucrose metabolism pathway. The findings revealed that 23 genes presented opposite expression pattern between 3 °C and 21 °C, and 62 chilling-related candidate genes were obtained. Sweetness loss in Hami melons was enhanced at storage temperatures of 3 °C and 0.5 °C. Furthermore, storage at 3 °C was found to decelerate Hami melon softening, as the degradation of pectin and expression of polygalacturonase (PG) were reduced. Moreover, storage at 0.5 °C promoted starch degradation by regulating the expression of α-amylase (AMY) and β-amylase (BMY) genes, subsequently, the levels of soluble sugars increased, potentially preventing physiological or cellular damage from cold stress in the melon fruit. These results indicated that softening was delayed at 3 °C, but the sweetness of the Hami melon was negatively affected at the level of gene transcription, explaining the faded sweetness of cold-stored melon fruit. [ABSTRACT FROM AUTHOR]

This study performed a comparative analysis of the sensory and microbial profiles of light‐flavor Bijou (LFD) from Taiyuan (Shanxi Province) and Suizhou (Hubei Province) in China. The results of the electronic nose showed that the aromatic substances of the LFD from Taiyuan (TLFD) were significantly higher (p <.05), while alcohol and aldehyde substances were significantly lower (p <.05) compared with the LFD from Suizhou (SLFD). The average response values of sensors W1C (sensitive to aromatic hydrocarbons), W3C (sensitive to amine and aromatic components), W5C (sensitive to olefins, aromatics, and polar molecules), and W2S (sensitive to alcohol and aldehyde compounds) to TLFD were 0.26, 0.33, 0.34, and 7.72, whereas the response values to SLFD were 0.25, 0.32, 0.33, and 8.04, respectively. The electronic tongue results showed that the aftertaste A (bitter aftertaste) and aftertaste B (astringent aftertaste) of the TLFD were significantly higher (p <.05) and umami was significantly lower (p <.05) as compared to the SLFD. The relative intensities of the aftertaste A, aftertaste B, and umami indicators of TLFD were 0.10, −0.008, and −0.22, respectively, while those of SLFD were −0.23, −0.36, and 0.835, respectively. MiSeq high‐throughput sequencing results showed that TLFD exhibited lower fungal richness and diversity compared to SLFD. The dominant bacterial genera were mainly Bacillus (58.12%), Kroppenstedtia (10.11%), and Weissella (6.26%), and the dominant fungal genera were Saccharomycopsis (67.53%), Rasamsonia (9.90%), and Thermoascus (7.10%). Streptomyces and Staphylococcus were identified as the key characteristic microorganisms in TLFD, while Kroppenstedtia, Rasamsonia, and Thermoascus were the key characteristic microorganisms in SLFD. Correlation analysis indicated a stronger correlation between microorganisms and sensory characteristics in SLFD samples. This study provides valuable insights into the sensory and microbiological characteristics of LFD from different regions and offers a new perspective for understanding the production of differently flavored light‐flavor Baijiu. [ABSTRACT FROM AUTHOR]

Dynamic quality changes of jujube wine during 10 days (240 hr) fermentation were evaluated by electronic nose and electronic tongue combined with multivariate statistical analysis methods. Fermentation significantly reduced the relative content of aromatic compounds, but promoted the generation of alcohol, sour compounds, umami compounds, sulfur‐containing organics, and broad range sensitivity compounds. The results of principal component analysis and cluster analysis indicate that, according to the overall quality similarity, the whole fermentation process of jujube wine can be categorized into three stages: early stage (0–24 hr), middle stage (36–132 hr), and late stage (144–240 hr). By Multivariate Analysis of Variance, significant differences (p <.001) were observed among jujube wine samples in the three fermentation stages. Further analysis using Redundancy Analysis found that the major changes of jujube wine quality occurred in the middle stage of fermentation, particularly 36–132 hr. Practical applications: In the case of the wine production, employing of the appropriate fermentation time throughout the process can be problematic. Hence, in this paper, electronic nose and electronic tongue technology combined with multivariate statistical analysis methods were applied to reveal the dynamic changes in quality of jujube wine, which provided a promising instruction for quality control of jujube wine. [ABSTRACT FROM AUTHOR]

In the case of wine production, the selection of optimal pretreatment methods and starter cultures are the 2 key points before fermentation. In this research, the fresh jujube was separately underwent alcoholic fermentation at 20°C with 3 different pretreatment methods (with peel, without peel, and juice) and 5 different starter cultures, respectively. Color analysis, electronic sense analysis, bioactive compound analysis, and antioxidant activity analysis combined with multivariate statistical analysis were applied to evaluated the effects of pretreatment methods and starter cultures on the overall quality of jujube wine. It was found that both pretreatment methods and starter cultures have effects on the quality of jujube wines, in which pretreatment methods have much more significant effects. The jujube wines fermented with different pretreatment methods were classified clearly by their overall quality, and that of the jujube wines fermented with peel was the best among all, since it can not only enhance the color and flavor quality of the wine, but also maximize the preservation of bioactive compounds and antioxidant activity of jujube for better consumer acceptance. This will provide a theoretical reference and application basis for the quality improvement of jujube wine. [ABSTRACT FROM AUTHOR]

Palladium (Pd)‐catalyzed radical oxidative C−H carbonylation of alkanes is a useful method for functionalizing hydrocarbons, but there is still a lack of understanding of the mechanism, which restricts the application of this reaction. In this work, density functional theory (DFT) calculations were carried out to study the mechanism for a Pd‐catalyzed radical esterification reaction. Two plausible reaction pathways have been proposed and validated by DFT calculations. The computational results reveal that the generated alkyl radical prefers to add to the carbon monoxide (CO) molecule to form a carbonyl radical before bonding with the Pd species. Radical addition onto Pd followed by CO migratory insertion was unfavorable owing to the high energy barrier of the migratory insertion step. The regioselectivity of the C(sp3)−H carbonylation was also investigated by DFT. The results show that the regioselectivity is controlled by both the bond dissociation energy of the reacting C−H bond and the stability of the corresponding generated carbon radical. Competitive side reactions also affected the yield and regioselectivity owing to the rapid consumption of the stable radical intermediate. Carbonylation mechanism: DFT method M06‐L was used to investigate the mechanism of Pd‐catalyzed radical oxidative carbonylation of alkanes with alcohols to afford alkyl acid esters. The results show alkyl radicals prefer to add to the CO molecule to form a carbonyl radical before bonding with the Pd species. Regioselectivity is controlled by both the bond dissociation energy of reacting the C−H bond and the stability of the corresponding generated carbon radical. [ABSTRACT FROM AUTHOR]

Apocynum venetum tea is increasingly being recognized for its health benefits. Given that brewing conditions affect the flavor and quality of the final brew, optimal brewing conditions need to be determined to produce high‐quality A. venetum tea. In this study, different brewing strategies (hot brewing, room temperature brewing, and cold brewing) were used to prepare A. venetum tea. Subsequently, the physicochemical indexes, functional components, antioxidant activity, and aroma compounds of the brews were compared. The brewing conditions affected the soluble solid content of the brews, as well as their pH, color, polyphenol content, flavonoid content, and aroma compounds. Ketones and aldehydes were the most abundant aroma compounds in the teas prepared using the three brewing conditions. Hot brewing tea had the highest content of functional components and antioxidant activity with aromas of grassy alcohols and caramel, sweet, nutty furans and ethers. Room temperature brewing tea was rich in esters with floral and fruity aromas. In contrast, cold brewing tea had a blue‐green color; the most abundant compound in this tea was 2,5‐dimethylbenzaldehyde, and it had a grassy and floral aroma. These results showed that hot brewing is the most suitable method for Apocynum preparation of A. venetum tea. Practical applications: Apocynum venetum tea has become an ingredient in natural health teas in recent years. The brewing conditions will affect the flavor and quality of the final brewing. Therefore, it is necessary to determine the best brewing conditions to produce high‐quality A. venetum tea, so as to provide theoretical support for the determination of brewing conditions for A. venetum tea. [ABSTRACT FROM AUTHOR]

The influence of the alcohol, as the hydrogen donor, on the efficiency and selectivity of the asymmetric transfer hydrogenation (ATH) of imines is reported for the first time. This discovery not only leads to a highly enantioselective access to N-aryl and N-alkyl amines, but also provides new insight into the mechanism of the ATH of imines. Both experimental and computational studies provide support for the reaction pathway involving an iridium alkoxide as the reducing species. [ABSTRACT FROM AUTHOR]

The influence of the alcohol, as the hydrogen donor, on the efficiency and selectivity of the asymmetric transfer hydrogenation (ATH) of imines is reported for the first time. This discovery not only leads to a highly enantioselective access to N-aryl and N-alkyl amines, but also provides new insight into the mechanism of the ATH of imines. Both experimental and computational studies provide support for the reaction pathway involving an iridium alkoxide as the reducing species. [ABSTRACT FROM AUTHOR]

Inoculation of the bacterial cells of microbial seed coating agents (SCAs) into the environment may result in limited survival and colonization. Therefore, the application efficacy of an encapsulated microbial seed coating agent (ESCA) was investigated on potted cotton plants; the agent was prepared with polyvinyl alcohol, sodium dodecyl sulfate, bentonite, and microencapsulated Bacillus subtilis SL-13. Scanning electron micrography revealed that the microcapsules were attached to ESCA membranes. The ESCA film was uniform, bubble-free, and easy to peel. The bacterial contents of seeds coated with each ESCA treatment reached 106 cfu/seed. Results indicated that the germination rate of cotton seeds treated with ESCA4 (1.0% (w/v) sodium alginate, 4.0% polyvinyl alcohol, 1.0% sodium dodecyl sulfate, 0.6% acacia, 0.5% bentonite, and 10% (v/v) microcapsules) increased by 28.74%. Other growth factors of the cotton seedlings, such as plant height, root length, whole plant fresh weight, and whole plant dry weight, increased by 52.70%, 25.13%, 46.47%, and 33.21%, respectively. Further analysis demonstrated that the peroxidase and superoxide dismutase activities of cotton seedlings improved, whereas their malondialdehyde contents decreased. Therefore, the ESCA can efficiently improve seed germination, root length, and growth. The proposed ESCA exhibits great potential as an alternative to traditional SCA in future agricultural applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • 330 MPa–450 MPa UHP treatment made the jujube juice more stable and colorful, and achieves the sterilization effect. • UHP treatment retarded jujube juice swollen bags by affecting the abundance of dominant microflora genera in jujube juice. • UHP treatment improved flavor quality of jujube juice by affecting the content of nine volatile compounds (VIP>1). • 330 MPa UHP treatment was the best for storage, color, stability, microbial community structure, and flavor of jujube juice. Ultra-high-pressure (UHP 1 1 Abbreviations: UHP, Ultra-high pressure; VIP, Variable importance in the projection; GC-IMS, Gas chromatography-ion mobility spectroscopy; cAMP, Cyclic adenosine monophosphate; PPO, Polyphenol oxidase; NGS, Next-generation sequencing; HPP, High pressure processing; MRS, DeMan, Rogosa, and Sharpe; PCA, Plate Count Agar; PDA, Potato Dextrose Agar; PCR, Polymerase chain reaction; HPLC, High performance liquid chromatography; ROAV, Relative odor activity value; LEfSe; Linear discriminant analysis Effect Size PLS-DA, Cluster analysis and Partial Least Squares Discriminant Analysis; CFU, Colony-forming units; UPGMA, Unweighted pair-group method with arithmetic means; PCoA, Principal co-ordinates analysis; LDA, Linear Discriminant Analysis.) technology for cold pasteurization is a viable alternative to traditional heat sterilization for preserving food nutrients and flavor compounds during fruit juice processing. In this study, cutting-edge techniques, including high-throughput sequencing technology, intelligent bionic sensory systems, and metabolomics, were used to examine the impact of UHP treatment on microbial community composition, odor, and taste quality of jujube juice. The UHP treatment demonstrated its effect by inducing a reddish-yellow color in the jujube juice, thereby enhancing its brightness, overall color, and stability. The most significant enhancement was observed at 330 MPa. The microorganisms responsible for spoilage and deterioration of jujube juice during storage were categorized into three clusters: bacterial clusters at 0–330 MPa, 360–450 MPa, and 480–630 Mpa. The results showed no distinct distribution patterns for fungi based on the pressure strength. The dominant bacterial genera were Lactobacillus , Nocardia , Achromobacter , Enterobacter , Pseudomonas , Mesorhizobium , and Rhodococcus , whereas the dominant fungal genera were yeast and mold. Notably, Lactobacillus , Achromobacter , Enterobacter , and Pseudomonas were responsible for the significant differences between the 360 MPa to 450 MPa and 480 MPa to 630 MPa clusters in terms of bacterial spoilage, whereas Torulaspora , Lodderomyces , Wickerhamomyces , and Fusarium were the primary fungal spoilage genera. UHP treatment exerted no significant impact on the taste of jujube juice but influenced its sourness. Treatment at 330 MPa had the most pronounced effect on the presence of aromatic compounds and other odorants, which were substantially increased. Further analysis revealed the prevalence of organic acids, such as malic acid, succinic acid, and tartaric acid, in jujube juice and demonstrated a consistent relationship between changes in organic acids and sourness. In addition, nine distinct odorants with VIP values greater than 1 were identified in the jujube juice. Among these, methyl acetate and methyl caproate exhibited substantial increases following the UHP treatment at 330 MPa. [ABSTRACT FROM AUTHOR]

Aroma is among the principal quality indicators for evaluating Baijiu. The aroma profiles of sauce-flavor Baijiu produced by 10 different manufacturers were determined by GC-IMS. The results showed that GC-IMS could effectively separate the volatile compounds in Baijiu, and a total of 80 consensus volatile compounds were rapidly detected from all samples, among which 29 volatile compounds were identified, including 5 alcohols, 14 esters, 2 acids, 2 ketones, 5 aldehydes, and 1 furan. According to the differences in aroma profile found by multivariate statistical analysis, these sauce-flavor Baijiu produced by 10 different manufacturers can be further divided into three types. The relative odor activity value of the identified volatile compounds indicated that seven volatile compounds contributed most to the aroma of sauce-flavor Baijiu in order of aroma contribution rate, and they were ethyl hexanoate, ethyl pentanoate, ethyl 2-methylbutanoate, ethyl octanoate (also known as octanoic acid ethyl ester), ethyl 3-methylbutanoate, ethyl butanoate, and ethyl isobutyrate. Correspondingly, the main aromas of these sauce-flavor Baijiu produced by 10 different manufacturers were sweet, fruity, alcoholic, etheral, cognac, rummy, and winey. On the one hand, this study proved that GC-IMS is well adapted to the detection of characteristic volatile aroma compounds and trace compounds in Baijiu, which is of positive significance for improving the aroma fingerprint and database of sauce-flavor Baijiu. On the other hand, it also enriched our knowledge of Baijiu and provided references for the evaluation and regulation of the flavor quality of sauce-flavor Baijiu. [ABSTRACT FROM AUTHOR]

Bacterial communities that enrich in high‐temperature Daqu are important for the Chinese maotai‐flavor liquor brewing process. However, the bacterial communities in three different types of high‐temperature Daqu (white Daqu, black Daqu, and yellow Daqu) are still undercharacterized. In this study, the bacterial diversity of three different types of high‐temperature Daqu was investigated using Illumina MiSeq high‐throughput sequencing. The bacterial community of high‐temperature Daqu is mainly composed of thermophilic bacteria, and seven bacterial phyla along with 262 bacterial genera were identified in all 30 high‐temperature Daqu samples. Firmicutes, Actinobacteria, Proteobacteria, and Acidobacteria were the dominant bacterial phyla in high‐temperature Daqu samples, while Thermoactinomyces, Staphylococcus, Lentibacillus, Bacillus, Kroppenstedtia, Saccharopolyspora, Streptomyces, and Brevibacterium were the dominant bacterial genera. The bacterial community structure of three different types of high‐temperature Daqu was significantly different (p <.05). In addition, the results of microbiome phenotype prediction by BugBase and bacterial functional potential prediction using PICRUSt show that bacteria from different types of high‐temperature Daqu have similar functions as well as phenotypes, and bacteria in high‐temperature Daqu have vigorous metabolism in the transport and decomposition of amino acids and carbohydrates. These results offer a reference for the comprehensive understanding of bacterial diversity of high‐temperature Daqu. [ABSTRACT FROM AUTHOR]

Background: Cantaloupe is susceptible to cold stress when it is stored at low temperatures, resulting in the loss of edible and commercial quality. To ascertain the molecular mechanisms of low temperatures resistance in cantaloupe, a cold-sensitive cultivar, Golden Empress-308 (GE) and a cold-tolerant cultivar, Jia Shi-310 (JS), were selected in parallel for iTRAQ quantitative proteomic analysis. Results: The two kinds of commercial cultivars were exposed to a temperature of 0.5 °C for 0, 12 and 24 days. We found that the cold-sensitive cultivar (GE) suffered more severe damage as the length of the cold treatment increased. Proteomic analysis of both cultivars indicated that the number of differentially expressed proteins (DEPs) changed remarkably during the chilly treatment. JS expressed cold-responsive proteins more rapidly and mobilized more groups of proteins than GE. Furthermore, metabolic analysis revealed that more amino acids were up-regulated in JS during the early phases of low temperatures stress. The DEPs we found were mainly related to carbohydrate and energy metabolism, structural proteins, reactive oxygen species scavenging, amino acids metabolism and signal transduction. The consequences of phenotype assays, metabolic analysis and q-PCR validation confirm the findings of the iTRAQ analysis. Conclusion: We found that the prompt response and mobilization of proteins in JS allowed it to maintain a higher level of cold tolerance than GE, and that the slower cold responses in GE may be a vital reason for the severe chilling injury commonly found in this cultivar. The candidate proteins we identified will form the basis of future studies and may improve our understanding of the mechanisms of cold tolerance in cantaloupe. [ABSTRACT FROM AUTHOR]

Rice wine, a traditional fermented alcoholic beverage in China, is produced with grains such as rice, which are fermented with saccharifying starter-koji. Its flavor quality is closely associated to the starter culture-koji, which is made by mixing botanical materials with high-class glutinous rice in certain ecological context. However, there are few reports on the microbial community structure of rice wine koji. In this paper, bacterial community structures of rice wine koji were analyzed using 16S rRNA gene sequencing based on Illumina MiSeq high-throughput technology in 20 samples collected from Xiaogan area, Hubei province and Dazhu area, Sichuan province (10 from each area). We found rice wine koji flora mainly consisted of Weissella, Lactobacillus, Lactococcus, Bacillus, Enterococcus, and Cronobacter, with relative abundances of 29.49%, 10.93%, 8.85%, 4.75%, 1.16% and 1.15%, respectively, as well as an accumulative average relative abundance of 58.71%. They all belonged to Firmicutes and Proteobacteria—the two known dominant genus. Genus-level PCA (Principal component analysis) and OTU-level PCoA (Principal coordinates analysis) based on unweighted UniFrac distances showed that the bacterial community structure differed significantly between the samples from the 2 areas. 7 OTUs were detected in all samples, accounting for 4.4% of the total qualified assembly. Among the 7 OTUs, 3 OTUs were identified as Enterococcus, 2 OTUs were identified as Cronobacter, 1 OTU was identified as Bacillus and 1 OTU was identified as Alkaliphilus. Fifty-eight lactic acid bacteria (LAB) strains were isolated from the 20 koji samples with traditional microbial methods. Among them, Enterococcus faecium and Pediococcus pentosaceus were the dominant LAB isolates, with relative abundances of 51.72% and 31.03%. Despite the differences, a large number of shared bacteria were detected in samples from the two areas. [ABSTRACT FROM AUTHOR]

Calcium-dependent protein kinase (CDPK) plays an important role in plant resistance to disease. In this study, we assessed CDPK activity in Hami melons during Penicillium infection, in order to investigate the possible role of CDPK in this context. The results showed the induction of CDPK by Penicillium infection may contribute to the early stages of disease resistance in Hami melons. In order to further study the molecular mechanisms underlying this response, relatively high expression of HmCDPK1 was screened form the transcriptome database of Hami melons. Bioinformatics analysis showed HmCDPK1 had a length of 2365 bp, with a maximum open reading frame of 1560 nucleotides, encoding 519 amino acids with a molecular weight of 58,646.83. Moreover, its theoretical isoelectric point was 6.34, as a hydrophilic and non-transmembrane protein. Real-time quantitative PCR showed the transcript of HmCDPK1 was persistently increased after Penicillium infection and reached its maximum at 12 h, being significantly higher than in non-infected plants. These results suggest the induction of CDPK activity and HmCDPK1 expression in the early response of Hami melons to Penicillium may contribute to the resistance against this infection. [ABSTRACT FROM AUTHOR]

To investigate the bacterial profiles and taste characteristics of rice wine from the Xiaogan and Dazhou regions, this study employed a combination of High-throughput sequencing, traditional pure culture techniques, and bionics equipment. The findings revealed a significant difference (P < 0.05) in bacterial diversity and community structure between the rice wine from Xiaogan and Dazhou. In particular, Leuconostoc , Lactococcus , Lacticaseibacillus , Exiguobacterium , Gluconobacter , Streptococcus , and Pantoea were significantly enriched in Xiaogan rice wine, Limosilactobacillus , Pediococcus , and Lactobacillus were significantly enriched in Dazhou rice wine. Notably, the most dominant group of bacteria in rice wine was lactic acid bacteria (LAB), and the main culturable isolates were Limosilactobacillus fermentum and Pediococcus pentosaceus. Additionally, the dominant bacterial genera showed a significant correlation with the taste characteristics of rice wine. Limosilactobacillus , Pediococcus , Lactobacillus , and Pseudomonas were positively correlated with the lactic acid, citric acid, pH value, Ala, Ile, and Leu of rice wine. Meanwhile, Exiguobacterium , Lacticaseibacillus , and Streptococcus were positively correlated with the richness of rice wine. This study provides insights into the bacterial diversity and taste characteristics of rice wine from different regions of the Yangtze River Basin and highlights the potential of traditional fermented foods as resources for LAB. • Bacterial communities in rice wines from different regions differed significantly. • Mainly lactic acid bacteria were isolated from traditionally fermented rice wine. • A relationship was found between the bacteria and taste characteristics in rice wine. [ABSTRACT FROM AUTHOR]

In this study, we performed a comparative analysis of fungal communities and cultivable yeast isolates in rice wine from the Xiaogan and Dazhou regions using Illumina MiSeq high-throughput sequencing technology and traditional culture-dependent methods. And we further explored the correlation between the sensory quality and fungal communities in rice wine. The results demonstrated no significant difference (P > 0.05) in the abundance and diversity of fungal communities and cultivable yeast isolates between Xiaogan and Dazhou rice wine. The dominant fungal genera were Rhizopus and Saccharomyces , with Saccharomyces cerevisiae accounting for the greatest proportion of yeast isolates. The rice wine samples could be divided into two types based on the composition of fungal communities. Type 1 mainly contained Rhizopus and Saccharomyces , while type 2 mainly contained Rhizopus. Properties such as lightness, blueness-yellowness, methane levels, ethanol levels, organic sulfide content, and soluble solids content accounted for the main differences between the two types of rice wine. In addition, Candida and Clavispora showed a significant positive correlation (P < 0.05) with the aromatic substances in rice wine. The findings of the study enrich our understanding of traditional rice wine, providing meaningful information for the improvement and development of the traditional rice wine industry. • Xiaogan and Dazhou rice wine were explored by various technological methods. • Clavispora and Mucor were biomarkers for rice wine samples from the Xiaogan and Dazhou regions, respectively. • S. cerevisiae accounted for the greatest proportion of yeast species in rice wine sample isolates from the two regions. • There were covariability between sensory quality of rice wine and Rhizopus , Saccharomyces , Candida , Clavispora , and Mucor. • We found a strongly positive correlation that the Candida and Clavispora with aromatic substances. [ABSTRACT FROM AUTHOR]

Calcium ions are second messengers in plant signal transduction involved in plant growth and development and the response to stress. Calcium-dependent protein kinase (CDPK) is calcium ion receptor functioning in plant disease resistance. Herein, we investigated changes in CDPK activity and resistance to Penicillium in postharvest Hami melons after different treatments. The non-infection group was permeated with calcium chloride (CaCl 2) solution, while the infection group was permeated with CaCl 2 solution and infected with Penicillium. CDPK activity was elevated in both groups but was higher in the infection group. Analysis of the molecular mechanism of CPDK in Penicillium infection revealed the 1635-bp HmCDPK2 gene with an open reading frame of 1239 nucleotides, encoding a protein of 412 amino acids with a molecular weight of 46161.61 Da and a theoretical isoelectric point of 5.00. The HmCDPK2 protein shares 40.11% tertiary structure similarity with CDPK from the apicomplexan parasite Plasmodium Bergheii (PDB ID 3Q5I). Fluorescence quantitative PCR results showed that expression of HmCDPK2 was upregulated in the infection group relative to the non-infection group, peaking at 12 h after treatment. We conclude that Hami melon develops resistance to Penicillium infection by regulating CDPK activity and upregulating HmCDPK2 expression. • Penicillium infection increased CDPK activity. • A novel HmCDPK2 genes from Hami melon fruit was isolated and identified. • The HmCDPK2 gene responded to Penicillium infection in the early stages of stress. [ABSTRACT FROM AUTHOR]

Density functional theory calculations were performed to reveal the mechanisms of Pd‐catalyzed cascade carbocyclization‐borylation and arylation reactions. The computational results indicate that the reactions start with allylic C−H cleavage through concerted metalation‐deprotonation and an intramolecular exo‐type allene insertion to form a six‐membered carbocycle intermediate. The regioselectivity of insertion could be explained by frontier molecular orbital theory and natural population analysis calculation. In the absence of extra nucleophiles, η1/η3‐isomerization followed by acetate‐assisted deprotonation could yield polyene product. When nucleophile was added to the reaction system, transmetalation and subsequent reductive elimination could give the exo‐substituted triene as major product. Meanwhile, η1/η3‐isomerization, transmetalation, and reductive elimination could afford the endo‐isomer as side product. The regioselectivity of further functionalization is controlled by the competition of transmetalation and η1/η3‐isomerization. The computational results show that both exo‐ and endo‐boronation product could be observed when bis(pinacolato)diboron is added as nucleophile. However, only exo‐phenylation product is observed when phenylboronic acid is used as nucleophile because of the high free‐energy barrier for reductive elimination from aryl η3‐allylic palladium. Show me the way: DFT calculations were employed to study the mechanism and origin of regioselectivity of cascade carbocyclization‐functionalization reactions. [ABSTRACT FROM AUTHOR]

Highlights • Gold Queen Hami melon stored at 3 °C have the best fruit quality. • Two novel MYB genes from Gold Queen Hami melon fruit were isolated and identified. • Storage at 3 °C enhanced FAD and ATPase activity, inhibited lipoxygenase activity. • Cold stress in fruits was alleviated by JhMYB24 and JhMYB48 upregulation. Abstract Low temperature storage prolongs the postharvest life of various fresh fruits and vegetables. However, the actual storage temperature may also significantly influence fruit and vegetable quality. In the present study, we stored Gold Queen Hami melons at three different temperatures [21 °C (control), 3 °C, and 0.5 °C (0 ± 0.5 °C)] for 36 days. The humidity for all three temperatures conditions was between 75% and 85%. The results indicated a correlation between chilling injury in Gold Queen Hami melons and storage temperature and time. Different degrees of chilling injury in Gold Queen Hami melons were observed after storage at 3 °C and 0.5 °C, whereas these were detected later when stored at 3 °C. In addition, the rotting rate, weight loss rate, and chilling injury index at 3 °C were significantly lower compared to that at 0.5 °C storage temperature. Compared to other temperatures, storage at 3 °C was associated with a delay in fruit rotting, sustained high fatty acid desaturase and adenosine triphosphatase (ATPase) activity, a decrease in lipoxygenase activity, enhanced cold resistance, and extended total storage period. At 21 °C, no chilling injury was observed, although extensive weight loss and high rotting rates were detected. Moreover, two highly expressed genes, namely, JhMYB24 and JhMYB48 , were screened and selected from the Gold Queen Hami melon transcriptome database. Real-time PCR analysis showed that the expression of JhMYB24 and JhMYB48 continuously increased under cold stress and peaked at the 18th day of cold storage. The expression of JhMYB24 and JhMYB48 at 3 °C was significantly higher than that at 0.5 °C or 21 °C. Together, our results demonstrate that regulating enzyme activity and upregulating the expression of JhMYB24 and JhMYB48 alleviate cold stress in fruits stored at 3 °C, thereby maintaining high fruit quality. [ABSTRACT FROM AUTHOR]

In this study, the differences in bacterial community structure and taste quality among the three different colored high-temperature Daqu (HTD) produced by Enterprise-A were investigated. Furthermore, these HTD were compared to HTD produced by local Enterprise-B. The results revealed yellow HTD of Enterprise-A showed significantly higher bacterial richness and diversity (P < 0.05). The dominant bacterial genera were Bacillus (27.09%), Lentibacillus (21.28%), Kroppenstedtia (12.68%), Thermoactinomyces (8.83%). The electronic tongue detection showed that black HTD presented significantly higher taste attributes, such as sourness, astringency, and bitter aftertaste (P < 0.05). Highly significant positive correlations between Bacillus with umami and saltiness were observed (P < 0.01), while a highly significant negative correlation was found between Bacillus and sourness (P < 0.01). Furthermore, the PCoA and cluster analysis revealed that the three colored HTD samples from the same enterprise were closer to each other. Finally, 84 bacterial strains were isolated from the HTD of Enterprise-A using pure culture methods, including B. amyloliquefaciens , B. licheniformis , Caldibacillus hisashii , and Pediococcus acidilactici. This study provides a greater understanding of the quality of HTD from Enterprise-A and reveals that the production process employed by different enterprises has a greater impact on the microbial community structure of HTD, compared to the differences in temperature during fermentation. • There were differences in microbiota and sensory of different colored HTD. • The highest bacterial richness and diversity were found in yellow HTD. • Black HTD had a particularly unique taste quality. • The differences in HTD of different enterprises were greater than those of colors. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective construction of axially chiral aryl‐naphthopyran skeletons was realized by organocatalytic atroposelective intramolecular [4+2] cycloaddition of in situ generated vinylidene ortho‐quinone methides, from 2‐ethynylphenol derivatives, with alkynes. Through this method, the heteroatropisomers were obtained with excellent yields and enantioselectivities. Moreover, a speculative model of the stereochemical outcome is proposed based on preliminary mechanistic studies. The products having various functional groups can be easily transformed into valuable intermediates as either potential ligands or organocatalysts. [ABSTRACT FROM AUTHOR]

The enantioselective construction of axially chiral aryl-naphthopyran skeletons was realized by organocatalytic atroposelective intramolecular [4+2] cycloaddition of in situ generated vinylidene ortho-quinone methides, from 2-ethynylphenol derivatives, with alkynes. Through this method, the heteroatropisomers were obtained with excellent yields and enantioselectivities. Moreover, a speculative model of the stereochemical outcome is proposed based on preliminary mechanistic studies. The products having various functional groups can be easily transformed into valuable intermediates as either potential ligands or organocatalysts. [ABSTRACT FROM AUTHOR]

In this study, 11 strains of lactic acid bacteria (LAB) from 4 species were comprehensively characterized for their ability to improve the functional properties and flavor quality of jujube–wolfberry composite juice. The results revealed that the jujube–wolfberry fresh juice was a favorable substrate for LAB growth, and the total number of LAB colonies remained above 7.93 log CFU/mL after fermentation. Fermentation with Lactiplantibacillus plantarum 9-2 (LP9-2) increased the total phenolic content by 16.67% and reduced the total flavonoid content by 14.15%; correspondingly, the antioxidant capacity significantly increased (p < 0.05) and was positively correlated with the content of gallic acid and rutin. In total, 56 volatile compounds were identified and quantified from the fermented juice. In total, 11 volatile compounds with relative odor activity value ≥ 1 were identified. In particular, LP9-2 increased the levels of (E)-2-hexenal, hexanal, and benzaldehyde, which resulted in an enhanced "jujube and wolfberry" flavor in the final product. • Fermentation enhances the antioxidant activity of jujube-wolfberry composite juice. • Lactic acid bacteria fermentation increased the content of acid, alcohol and ester. • A total of 56 volatile compounds were identified and quantified. • A total of 11 key volatile compounds with rOAV >1 were identified. [ABSTRACT FROM AUTHOR]

The present investigation was carried out to determine the inter-relationship between some physiological attributes of cotton and encapsulated Rs-198 strain. The pot experiment had seven treatments (with or without encapsulated bacteria under different salt stress conditions, 10 replicates) and was carried out in the greenhouse during April–June 2014. Pot results showed that the inoculated encapsulated Rs-198 significantly increased the plant biomass under 0.5% salt stress. Besides, an approximately 19.47% increase in the soluble protein content of cotton with encapsulated Rs-198 inoculated in salt condition and relatively higher chlorophylls a, b and carotenoid concentrations of 0.626, 0.304, and 0.564 mg/g, respectively, were maintained. The proline content and peroxidase activity in cotton plants inoculated Rs-198 under 0.5% salt stress of were reduced by 42.30% and by 24.98%, respectively. In conclusion, application of encapsulated Rs-198 strain was effective in relieving salt stress under saline conditions. microcapsule bioinoculants are potential alternatives for sustainable agriculture due to their low cost of production. [ABSTRACT FROM AUTHOR]

In this study, we comparatively analyzed the microbial community structure of light-flavored Daqu (LFD) from Taiyuan and Suizhou regions using a combined strategy of single-molecule real-time sequencing and pure culture techniques. The results indicated that the dominant bacteria and fungi in all LFD were Bacillus licheniformis (22.61%) and Saccharomycopsis fibuligera (80.98%), respectively. The abundance and diversity of fungi were significantly lower in the LFD from Taiyuan region (Taiyuan-LFD) (p < 0.05). The LFD from both regions exhibited differences mainly in terms of lactic acid bacteria and thermophilic flora; Leuconostoc were significantly enriched in the Taiyuan-LFD, whereas Weissella , Thermoascus aurantiacus , and Thermoactinomyces sanguinis were significantly enriched in the LFD from Suizhou region (Suizhou-LFD) (p < 0.05). The correlating network between the microbiota of the Suizhou-LFD was denser than the Taiyuan-LFD. The core microorganisms of the LFD in both regions were mainly Ba. licheniformis , Burkholderia contaminans , and Saccharomycopsis fibuligera. Bacillus , lactic acid bacteria, and yeast isolated from all samples mainly consisted Ba. licheniformis (28 strains), Pediococcus pentosaceus (22 strains), and Saccharomycopsis fibuligera (44 strains), respectively. This study provided insights into the variations in microbiota in the LFD from different regions and laid the foundation for screening excellently suited functional microorganisms for brewing. • The microbial community in the light-flavor Daqu of Taiyuan and Suizhou regions was fully revealed. • The fungal diversity and abundance of the LFD in the Taiyuan region were lower than LFD in the Suizhou region. • Bacillus licheniformis and Saccharomycosis fibulifera were the main core flora of LFD in two regions. [ABSTRACT FROM AUTHOR]

For the first time, the influence of the alcohol on efficiency and selectivity of an asymmetric transfer hydrogenation of imines is reported. [ABSTRACT FROM AUTHOR]

In this work, two kinds of polyoxometalate (POM) nanoparticles with controlled shapes and structures were synthesized by micelle directed method and then composited with TiO 2 via calcination to remove the surfactants owing to the excellent electronic storage and transmission ability of POM, finally obtaining two kinds of TiO 2 composites with highly dispersed and small-sized POM nanoparticles (∼1 nm). The TiO 2 composites were then induced into the photoanodes of dye-sensitized (N719) solar cells (DSSCs). The separation of electron-holes becomes more favorable due to the nanostructure and high dispersion of POM which provide more active sites than pure POM tending to agglomeration. The TiO 2 composite photoanodes finally yielded the power conversion efficiency (PCE) of 8.4% and 8.2%, respectively, which were 42% and 39% higher than the pristine TiO 2 based anodes. In addition, the mechanisms of POM in DSSC are proposed. [ABSTRACT FROM AUTHOR]

Long-term cold storage of Hami melons (Cucumis melo var. saccharinus) induces severe chilling injuries, downgrading their storage quality. Three different concentrations (1, 3, and 9 mM) of exogenous salicylic acid (SA) were applied under cold stress conditions (0.5 ± 0.5 °C) to prolong the shelf-life of cold-sensitive 'Golden Empress-308′ (GE-melon) Hami melons. Afterward, the phenotypic index, bioinformatics of CmGSTs , expression patterns of CmGSTs , endogenous SA content, molecular docking, and molecular dynamics simulation were investigated. The phenotypic index indicated that low concentrations (1 and 3 mM) of SA ameliorated chilling injuries, whereas a high concentration of SA (9 mM) treatment adversely affected the GE-melons. The RT-qPCR analysis determined that SA treatment induced five out of seven CmGST -containing SA-response cis -elements. The content of endogenous SA was elevated by exogenous SA. Interestingly, both high and low levels of endogenous SA promoted chilling injuries in GE-melons under cold stress conditions. Furthermore, molecular docking and molecular dynamics simulation signaled that SA bound to the target CmGSTs in a stable conformation. In conclusion, administration of a low concentration of SA enhances cold tolerance in Hami melons by modulating the SA-responsive CmGSTs under cold stress conditions. • A low concentration of SA prolonged the storage of GE-melon. • CmGST genes containing SA-response cis -elements were induced by exogenous SA. • SA bound to its CmGSTs primarily through hydrogen-bonding interactions. • Both high and low levels of endogenous SA promoted chilling injuries in GE-melon. [ABSTRACT FROM AUTHOR]

Low temperature storage prolongs the postharvest life of various fresh fruit and vegetables. However, tropical fruit may suffer from cold stress during storage. Here, Jiashi melons was stored at 3 °C, and 0.5 °C for a period of 36 days, with storage at 21 °C serving as a control. Rotting was delayed at the lower temperatures compared to the control. Storage at 21 °C resulted in more severe weight loss and a high rotting rate. By day 36, the weight loss rate as a result of moisture reduction reached 11% in the control, but only 8% at the lower temperatures. Chilling injury was observed at both low temperatures over time, but its onset was later for storage at 3 °C. The fruit stored at 3 °C also scored better for rotting rate, weight loss rate, and a chilling injury index than fruit stored at 0.5 °C. Storage at 3 °C was associated with higher activity of peroxidase (POD), catalase (CAT), fatty acid desaturase (FAD), and adenosine triphosphatase (ATPase). The transcriptomes of the fruit were sequenced for the time points 0 d, 12 d and 24 d at all three storage temperatures. This identified a total of 415 co-expressed differential genes that are mainly involved in regulation of transcription, signal transduction, response to stress, lipid metabolism and other processes. The findings were corroborated by targeted RT-qPCR analysis. The expression levels of differentially expressed genes (DEGs) indicated that storage at 3 °C induced overexpression of the early cold-responsive genes ICE1 and calcium-dependent protein kinase (CDPK). Extended storage at 3 °C reduced the damage of low-temperature induced oxidative stress and altered lipid metabolism that otherwise would negatively affect cell membrane functions, so that cell homeostasis was maintained for longer. This was enabled by increased expression of MYB, auxin response factor, heat shock protein (HSPs), FAD synthetase and ATPase. This study provides insights in the molecular responses of Jiashi melon towards cold stress, and provides a theoretical basis for the development of new storage and preservation technologies. • Jiashi melon stored at 3 °C have the best fruit quality. • Transcriptomics analysis revealed DEPs changes in response to different temperatures. • Physiology and transcriptome revealed the cold response mechanism of Jiashi melon. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbiota and flavor of fermented grains were affected by fermentation rounds. • Physicochemical factors mainly exhibited depths heterogeneity. • Starch was the most influential physiochemical factor on the microbiota. • Fermented grains from two fermentation rounds had diverse flavors. To improve the utilization of raw materials, the fermentation of light-flavor Baijiu (LFB) will usually take two rounds of fermentation to the same batch of raw materials. The microorganisms involved in the fermented grains (FG) from these two fermentation rounds are the key to the quality formation of light-flavor style. Using Illumina MiSeq high-throughput sequencing and electronic-senses, it was found that the microbiota and flavor of FG for light-flavor Baijiu were mainly affected by fermentation rounds rather than depths, while the physicochemical factors were just the opposite. Starch was the most influential physiochemical factor on the microbiota. FG from the first fermentation round (FFRFG) had a higher fungal diversity, while FG from the second fermentation round (SFRFG) had a higher microbial richness and bacterial diversity. Monascus and the function of metabolism were significantly enriched in FFRFG; while Nocardia , Saccharomyces , Aspergillus and the functions of information storage and processing as well as cellular processes and signaling were significantly enriched in SFRFG. The flavor characteristics of FFRFG were mainly sourness as well as rich in sulfur organic compounds and broad range compounds, while that of SFRFG was mainly saltiness, umami, and bitterness, as well as rich in aromatic compounds. The findings could contribute to a comprehensive understanding of the role of FG in LFB fermentation from the perspective of rounds and depths. [ABSTRACT FROM AUTHOR]

Routine analysis, electronic sensory methods, and HS-SPME-GC-MS were used to evaluate the effect of S. cerevisiae and S. cerevisiae + Bacillus licheniformis on the quality of jujube wine. The results show that all wine samples showed significant differences in color, taste, amino acids, organic acids, and aroma (p < 0.05), while the color quality of co-fermented jujube wine was better. On the sensory scale, co-fermentation improved the taste complexity of jujube wine with a unique flavor and typical aroma. HS-SPME-GC-MS analysis revealed 37 characteristic volatile compounds in co-fermented jujube wine. Therefore, using B. licheniformis in the wine fermentation process can significantly improve microbial biotransformation efficiency and flavor. Our results show that the mixed culture of B. licheniformis and S. cerevisiae could be a valuable tool to adjust volatile components and improve the aroma complexity of jujube wine. • Taste and aroma were profiled detected by electronic senses and HS-SPME-GC-MS. • Thirty-seven key flavor compounds are most likely to be important for co-fermented wine quality. • Multivariate statistical analysis is effective for the analysis of wine flavor. • Co-fermentation is most beneficial to the flavor of jujube wine. [ABSTRACT FROM AUTHOR]

[Display omitted] • Peak temperature affects microbiota, functions and flavor of low-temperature Daqu. • Each type of low-temperature Daqu contributed to the flavor of light-flavor Baijiu. • The taste profiles of different types of low-temperature Daqu differed more. • Bacteria mainly affected the taste, while fungi mainly affected the aroma. Light-flavor Baijiu is made from grain materials using a combination of three types of low-temperature Daqu (Hongxin, Houhuo, and Qingcha). This study comprehensively examined the microbial structure, microbial functions, and flavor characteristics of the three types of low-temperature Daqu using high-throughput sequencing and electronic senses, and it further clarified the relationship between the microbiota and flavor in low-temperature Daqu. The results showed that Hongxin had the highest bacterial richness and diversity, while Houhuo had the lowest. Both fungal richness and diversity were significantly higher in Qingcha than in Hongxin and Houhuo. The differences in peak temperature during Daqu-making led to significant differences in the structure of microbial communities, microbial functions, and flavor quality in the three types of low-temperature Daqu, and could be leveraged for screening and enriching functional microorganisms for Baijiu-making. Co-exclusion patterns between lactic acid bacteria and Bacillus in low-temperature Daqu resulted in a negative correlation between amino acid transport metabolism and carbohydrate transport metabolism. The different types of low-temperature Daqu had distinct flavor profiles, and the differences in the taste profiles were more significant. Dominated by Thermoactinomyces and Lactobacillus , and together with Saccharopolyspora , Bacillus , Streptomyces , Saccharomycopsis , and Thermoascus , they formed the core microbiota that influencing the flavor of low-temperature Daqu. The bacteria mainly influenced the taste of low-temperature Daqu, whereas the fungi mainly influenced the aroma. Each type of low-temperature Daqu contributed to the flavor of light-flavor Baijiu: Hongxin could elevate the levels of aromatic compounds, Houhuo could regulate the bitterness and sourness, and Qingcha could inhibit the generation of sulfur organic compounds. The results of the present study enrich and refine our knowledge of low-temperature Daqu, promoting the further evolution of traditional brewing methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lactic acid bacteria dominate in zha-chili and have a great impact on the quality. • Different rice varieties lead to differences in microbiota and flavor. • The differences in microbiota mainly affect the sourness and umami of zha-chilli. • Relationships among rice varieties, bacterial microbiota and flavor were clarified. The structure and diversity of bacterial communities in spontaneously fermented zha-chili prepared using two different rice varieties (glutinous rice and indica rice) were investigated using high-throughput sequencing. Through metabolic pathway prediction, electronic senses and metabolite analysis, the relationships among the rice varieties used for preparation and the bacterial microbiota, flavor, and organic acid/amino acid metabolites in zha-chili were elucidated. We observed that the structure of bacterial communities in zha-chili samples differed significantly with the rice variety used during fermentation (p < 0.05), and that there was a greater abundance of bacterial species in zha-chili prepared using glutinous rice. Lactic acid bacteria were predominant in zha-chili, with an average relative abundance of 77.09%. The aroma of zha-chili was influenced by the raw material itself, while the characteristic tastes of zha-chili — including sourness, umami and richness — were significantly correlated with the bacterial microbiota. In addition, the abundance of lactic acid bacteria was positively correlated with the levels of organic acids and negatively correlated with the levels of amino acids. This also made the zha-chili prepared using glutinous rice sourer and imparted more umami taste to the zha-chili prepared using indica rice. Our observations provide a reference for the evaluation of zha-chili quality and could effectively guide the improvement of zha-chili products. [ABSTRACT FROM AUTHOR]