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The genus Cinnamomum exhibits a rich variety of chemotypes and is an economically important essential oil (EO)-producing plant belonging to the family Lauraceae. Here, we aimed to explore the potential differences in the terpenoid (the principal components of EOs) biosynthesis pathways of different chemotypes at the molecular level in four Cinnamomum species—C. camphora var. linaloolifera, C. kanehirae, C. longipaniculatum, and C. micranthum. Gas chromatography–mass spectrometry (GC-MS) was employed to elucidate the discrepancies in the chemical profiles and compositions of leaf EO terpenoids among the four Cinnamomum species. The results revealed significant variations in leaf EO yields. The main constituents of the leaf EOs from C. camphora var. linaloolifera and C. kanehirae were the acyclic monoterpene linalool, and those of C. longipaniculatum and C. micranthum were the monoterpene eucalyptol and the sesquiterpene β-caryophyllene, respectively. Furthermore, a comparative transcriptome analysis of the leaves from the four Cinnamomum species revealed that differentially expressed genes (DEGs) were significantly enriched in terpene-related entries. Specifically, 42 and 24 DEGs were significantly enriched to the mevalonate (MVA)/2-methylerythritol 4-phosphate (MEP) pathways and terpene synthase (TPS) activity, respectively. Most genes encoding proteins involved in the terpenoid precursor MVA and MEP pathways exhibited differential expression across the four species, which correlated with the distinct terpenoid profiles observed in their leaf EOs. Four acyclic monoterpene linalool synthase genes—Maker00024100, Maker00014813, Maker00014818, and Maker00018424—were highly expressed in C. camphora var. linaloolifera and C. kanehirae. A monoterpene eucalyptol synthesis gene, Maker00001509, was highly expressed in C. longipaniculatum, and a sesquiterpene β-stigmasterol synthesis gene, Maker00005791, was highly expressed in C. micranthum. These expression levels were subsequently validated through quantitative real-time polymerase chain reaction (qRT-PCR). In conclusion, the combined results of the GC-MS and transcriptome analyses revealed a strong correlation between the metabolite content of the EOs and gene expression. This research contributes to a better understanding of the differences in terpene accumulation in various chemotypes of Cinnamomum at the molecular and mechanistic levels, laying a solid foundation for the cultivation of an ideal Cinnamomum variety. [ABSTRACT FROM AUTHOR]

In this study, the properties of konjac glucomannan with different molecular weights and their effects on the functional and structural properties of κ-carrageenan (κ-CA) composite gel were analyzed. Native konjac glucomannan (K1: Mw = 67,158 g/mol) was hydrolyzed by β-mannanase to obtain three konjac glucomannan with different molecular weights (K2: Mw = 65,124 g/mol, K3: Mw = 32,302 g/mol, and K4: Mw = 17,102 g/mol). The results showed that the hydrolyzed K2, K3, and K4 had lower viscosity, more loose and porous structure, shorter molecular chain and stronger antioxidant activity than native K1. K2 and K3 increased the hardness, gumminess, chewiness, water holding capacity and stronger antioxidant activity but decreased the cohesiveness, resilience, and transparency of κ-CA gel. Hierarchical cluster analysis confirmed that K2/κ-CA and K3/κ-CA gels had good gel properties with better texture and water holding capacity as compared to the other samples, which might be related to their smoother and more compact gel structure and enhanced hydrogen bond. The competition for water molecules between κ-CA and over degraded K4 induced the poor water holding capacity and gel structure for their composite gel. The results revealed the gelation changes of κ-CA composite gel affecting by konjac glucomannan with different molecular weights, and can lay a theoretical foundation for the development and application of their compound food additive. [ABSTRACT FROM AUTHOR]

Seaweed has attracted great attention as a healthy and nutritious food. Traditional seaweed processing plants mainly rely on manual visual inspection to identify and remove inferior seaweed. Accurate and rapid harvest period classification and impurity detection are key to improving productivity and processing speed in seaweed processing plants. Although many studies on seaweed have been conducted in laboratory environments, currently, the plants lack effective tools to obtain real-time and reliable information on seaweed quality. To address this challenge, the deep transfer learning-based computer vision was applied to identify inferior seaweeds, including those from the third harvest, fourth harvest, and impure seaweeds in this work. Specifically, YOLOv8 and YOLOv5 were utilized as base transfer learning models. By loading various pre-trained weight files, this study was able to automatically classify Porphyra haitnensis into four categories based on the harvest period and simultaneously detect four types of common impurities in it. Among the tested models, YOLOv8n-cls achieved the best trade-off in classifying the harvest period, with a Top-1 accuracy of 93.5%. This represented a significant improvement of 16% compared to the performance without transfer learning. The detection speed for a single image was 8.2 ms, and the model size was only 2.82 Mb. On the other hand, YOLOv8n exhibited outstanding performance in impurity detection, with a mean average precision of 99.14%, a single image detection speed of 4.3 ms, and a model size of 5.95 Mb. The results demonstrated the potential of YOLOv8 with transfer learning to objectively assist or even replace decision-making by assembly line workers. This study will not only enhance the quality control, production efficiency, and economic benefits of the seaweed processing industry but also drive the automation equipment and systems of seaweed-related enterprises towards greater intelligence and efficiency. [ABSTRACT FROM AUTHOR]

The unique edge states of the zigzag β-SiC7 nanoribbons aroused our attention, and therefore, based on first-principles calculations, we investigated their spin-dependent electronic transport properties by constructing controllable defects to modulate these special edge states. Interestingly, by introducing rectangular edge defects in the SiSi and SiC edge-terminated systems, not only the spin-unpolarized is successfully converted to completely spin-polarized, but also the direction of polarization can be switched, thus enabling a dual spin filter. The analyses further reveal that the two transmission channels with opposite spins are spatially separated and that the transmission eigenstates are highly concentrated at the relative edges. The specific edge defect introduced only suppresses the transmission channel at the same edge but reserves the transmission channel at the other edge. In addition, for the CSi and CC edge-terminated systems, an additional spin-down band exists due to spin splitting in the spin-up band at EF, so that besides the original spatially separated two spin-opposite channels, an extra spin channel is distributed at the upper edge, resulting in unidirectional fully spin-polarized transport. The peculiar spatially separated edge states and excellent spin filtering properties could open up further possibilities for β-SiC7-based electronic devices in spintronics applications. [ABSTRACT FROM AUTHOR]

Poor thermostability reduces the industrial application value of κ-carrageenase. In this study, the PoPMuSiC algorithm combined with site-directed mutagenesis was applied to improve the thermostability of the alkaline κ-carrageenase from Pseudoalteromonas porphyrae. The mutant E154A with improved thermal stability was successfully obtained using this strategy after screening seven rationally designed mutants. Compared with the wild-type κ-carrageenase (WT), E154A improved the activity by 29.4% and the residual activity by 51.6% after treatment at 50 °C for 30 min. The melting temperature (Tm) values determined by circular dichroism were 66.4 °C and 64.6 °C for E154A and WT, respectively. Molecular dynamics simulation analysis of κ-carrageenase showed that the flexibility decreased within the finger regions (including F1, F2, F3, F5 and F6) and the flexibility improved in the catalytic pocket area of the mutant E154A. The catalytic tunnel dynamic simulation analysis revealed that E154A led to enlarged catalytic tunnel volume and increased rigidity of the enzyme–substrate complex. The increasing rigidity within the finger regions and more flexible catalytic pocket of P. porphyrae κ-carrageenase might be a significant factor for improvement of the thermostability of the mutant κ-carrageenase E154A. The proposed rational design strategy could be applied to improve the enzyme kinetic stability of other industrial enzymes. Moreover, the hydrolysates of κ-carrageenan digested by the mutant E154A demonstrated increased scavenging activities against hydroxyl (OH) radicals and 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radicals compared with the undigested κ-carrageenan. [ABSTRACT FROM AUTHOR]

It is important to eliminate the fishy odor and improve the aroma quality of seafood. In this study, the Saccharina japonica (S. japonica) seedling, which is a new food material, was investigated for the effects of fermentation with Saccharomyces cerevisiae (S. cerevisiae) through sensory evaluation, GC–MS, and odor activity value (OAV) analysis. GC–MS analysis revealed the presence of 43 volatile compounds in the unfermented S. japonica seedling, with 1-octen-3-ol, hexanal, and trans-2,4-decadienal identified as the main contributors to its fishy odor. After fermentation with S. cerevisiae, 26 volatile compounds were identified in the S. japonica seedling. Notably, the major malodorous fish compounds, including 1-octen-3-ol, hexanal and trans-2,4-decadienal, were no longer present. The results indicate that fermentation with S. cerevisiae is an effective method for removing fishy malodor compounds and enhancing the volatile components with fruity, sweet, green, and floral notes in the Saccharina japonica seedling. This process facilitates the elimination of fishy malodor and enhance the fruity, sweet, green, and floral notes of S. japonica seeding and other seaweeds. [ABSTRACT FROM AUTHOR]

Citrus peels are rich in flavonoids, and some valuable flavonoids with health benefits, such as polymethoxyflavones (PMFs), are found almost exclusively in citrus peels. While the peels usually regarded as by-product, leading to source waste. As a traditional method, drying is helpful to increase added-value of peels which can be used as medicine. However, the variations in variety and quantity of flavonoids during drying processes of citrus peel remain unknown. In this study, Guanxi honey pomelo peel investigated the effect of different drying methods on flavonoids content in citrus peels. Five drying techniques, namely, freeze-drying (FD) and hot air drying (HAD) at 30 °C, 50 °C, 70 °C and 90 °C were used employed for drying the pomelo peels and HPLC-Q-TOF-MS analysis identified 39 flavonoids changes in flavonoids across samples. FD proved to better preserve most glycosidic flavonoids. Flavonoid aglycones could be better preserved in samples of HAD at 30 ℃, 50 ℃ HAD and 90 ℃ HAD. Specifically, HAD at 30 ℃ and 50 ℃ HAD is beneficial for obtaining more valued polymethoxyflavones such as 5-hydroxy-6,7,4′-trimethoxyflavone, 5,7,8,4′-tetramethoxyflavone and 3,5,6,7,8,3′,4′-heptamethoxyflavone. The 90℃ HAD resulted in the highest content of naringenin and 5,7,8,4′-tetramethoxyflavanone. This study demonstrated the transformation characteristics of flavonoids in pomelo peel under varying drying conditions, providing benefits for comprehensive utilization of pomelo peel in extracting valued-added flavonoids. [ABSTRACT FROM AUTHOR]

The aim of this paper was to explore the process of β-glucosidase-assisted extraction of flavonoids from thinned fruits of Guanxi pummelo and the inhibitory effect of the extracted flavonoids on tyrosinase. In this paper, the extraction amount of total flavonoids was used as the index, and the β-glucosidase activity, enzymatic hydrolysis pH, temperature and time were optimized by single factor and response surface experiments, and the inhibitory effect of total flavonoids extract on tyrosinase was studied. The results showed that the optimal conditions for the extraction of flavonoids from thinned fruits of Guanxi pummelo were as follows: β-Glucosidase enzyme activity 0.0128 U/mL, enzymolysis pH4.4, temperature 35 t, time 4.8 h. Under these conditions, the extraction amount of total flavonoids was 34.0 mg/g, the half maximal inhibitory concentration (IC50) of the flavonoids extract on tyrosinase was 0.31 mg/mL. The results of this study showed that the enzymatic process could significantly improve the extraction amount of flavonoids from thinned fruits of Guanxi pummelo, and the flavonoids from thinned fruits of Guanxi pummelo had strong tyrosinase inhibition. The results of this study provided a reference for the extraction and application of flavonoids from thinned fruits of Guanxi pummelo, which was conducive to promoting the high-value utilization of Guanxi pummelo. [ABSTRACT FROM AUTHOR]

Konjac glucomannan (KGM) is commonly blended with κ-carrageenan to improve the gel properties of food, which are mostly influenced by KGM purification. Control of ethanol pH for KGM purification is an easy and simple option to modify the properties of KGM, that tends to alter the gel properties of κ-carrageenan/KGM blends. In this study, the effect of ethanol at different pH (ranging from 2.5 to 12.5) on KGM was investigated, and the gels of κ-carrageenan with KGM purified by ethanol at different pH were prepared with microwave heating. With KGM purified with ethanol between pH 5.5 and 9.5, κ-carrageenan/KGM blends exhibited higher gel strength, hardness and water holding capacity than those of gel with native KGM, which was much related with the removal of impurity, the increased viscosity and altered structure of KGM, enhancing the interaction between κ-carrageenan and KGM. Poor gel properties of the blends were observed with KGM purified with ethanol at pH between 2.5 and 4.5 caused by KGM degradation, or at pH 12.5 due to the removal of acetyl groups. Thus, control of ethanol pH during KGM purification can easily and simply optimize the gel characteristics of κ-carrageenan/KGM blends to meet desired application requirements. [ABSTRACT FROM AUTHOR]

Plasma treatment as an effective strategy can simultaneously achieve surface modification and heteroatom doping. Here, an N/P-doped NiFeV oxide nanosheet catalyst (N/P-NiFeVO) constructed by Ar/PH3 plasma treatment is used to drive the oxygen evolution reaction (OER). The introduction of V species leads to the formation of an ultrathin ordered nanostructure and exposure of more active sites. Compared to the 2D NiFeV LDH, the prepared N/P-NiFeVO by plasma treatment possesses multiple-valence Fe, V and Ni species, which regulate the intrinsic electronic structure and enable a superior catalytic activity for the OER in alkaline media. Specifically, the N/P-NiFeVO only require an overpotential of 273 mV to drive the current density of 100 mA cm−2. What's more, the electrode can maintain a stable current density in a long-term oxygen evolution reaction (∼120 h) under alkaline conditions. This work provides new insight for the rational design of mixed metal oxides for OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Nitro-fatty acids (NO2-FAs) are a class of bioactive lipids that mediate metabolic, anti-oxidative stress, anti-inflammatory, and other signaling actions. Endogenously, NO2-FAs are derived from the non-enzymatic reactions of unsaturated fatty acids with reactive nitrogen species. The electrophilic properties of the nitro group results in NO2-FAs being able to undergo rapid and reversible reactions with biological nucleophiles, such as cysteine and histidine, thus supporting post-translational modifications of proteins. The reactions of NO2-FAs with biological nucleophiles regulate a range of key signaling pathways involved in gene expression responses, enzyme activity, and cellular processes. In disease animal models, NO2-FAs are produced under conditions of inflammation and oxidative stress and play a protective role in a variety of metabolic diseases, which have been associated with anti-atherosclerosis, blood-pressure lowering, and are involved in the regulation of glycolipid metabolism and insulin resistance. Based on these, more clinical studies might find a correlation between NO2-FAs levels and pathophysiology in patients with metabolic diseases. Importantly, NO2-FAs therapeutics are effective in clinical trials. In addition, dietary supplementation with nitrates and unsaturated fatty acids can endogenously increase NO2-FAs levels in mice and humans. These findings support dietary approaches that increase the endogenous levels of NO2-FAs might potentially reduce the risk of metabolic diseases. To identify the specific mechanism of action and therapeutic potential of NO2-FAs, we have summarized the main mechanisms of action of NO2-FAs in metabolic disease progression to provide insights for the development of new therapeutics for metabolic diseases. [ABSTRACT FROM AUTHOR]

Fruitlet core rot (FCR) is a worldwide fungal disease of pineapple, which occasionally occurs on susceptible cultivars in Taiwan. This study describes the fungal pathogens of FCR and their occurrence in Taiwan for the first time. A total of 51 fungal isolates were obtained from diseased fruitlets and blossom cups of 'TN20', a susceptible cultivar planted in Taiwan. These isolates were identified as the Talaromyces species T. amestolkiae, T. funiculosus, and T. stollii and Fusarium species F. ananatum, F. oxysporum, and F. annulatum based on phylogenetic analyses. All of them have been described as FCR pathogens in other countries, if considering that F. annulatum has often been misidentified as F. proliferatum. To facilitate identification, four pairs of species-specific primers were developed, which enabled rapid identification of T. amestolkiae, T. funiculosus, and T. stollii by multiplex polymerase chain reaction (PCR) and F. ananatum by PCR. Two types of diseased fruitlets, "wet" and "dry", were observed on 'TN20', and T. amestolkiae, T. funiculosus, T. stollii, and F. ananatum could be isolated from both types. In addition, Talaromyces and Fusarium species were isolated from blossom cups at high frequencies, but few fungi were isolated from healthy tissues. The specific primers designed in this study could provide a useful tool to study FCR in the future, and the findings could provide a better understanding of the ecology and epidemiology of FCR. [ABSTRACT FROM AUTHOR]

Mathematical models based on infrared spectroscopy and machine learning have been successfully used to trace the origin of soybeans. However, as previous research reported, it is necessary to employ spectra data that undergo multiple pre-processing operations in order to achieve optimal accuracy during model training. And these established models are only capable of predicting samples with identical spectra pre-processing. Specifically, baseline correction, which necessitates individual processing of each spectrum, requiring substantial investments of time and human resources with a large dataset. In this study, the spectra augmentation technique was proposed based on the theory of data augmentation, in order to simplify or even eliminate the pre-processing steps for the prediction dataset. The technique utilized a combination of the standard spectra pre-processed data and the "boost data" to train models, specifically, a total of 180 spectra, including 90 pre-processed standard spectra and 90 "boost" spectra. The "boost" data refers to data without the standard spectra pre-processing. On the prediction dataset without the standard spectra pre-processing, the model with the spectra augmentation technique had an accuracy of 0.91 for the recognition of Northeast China soybeans, while the accuracy of the model with the training method frequently reported in previous studies only reached 0.71, demonstrating that the model trained with the proposed technique possessed higher robustness and generalization capabilities. The spectra augmentation technique can maintain high accuracy while simplifying spectra pre-processing steps on prediction data, therefore, providing a more efficient and expedited method for practical food traceability and authentication. [ABSTRACT FROM AUTHOR]

Angelicae sinensis radix is commonly used in Chinese medicine and is also widely used as a spice and condiment in many countries. Due to the different geographical sources and processing methods, the contents of chemical components are different and affect the quality of Angelica sinensis radix. A simple and efficient method was established to comprehensively evaluate the quality of Angelica sinensis radix by combining HPLC fingerprint and single-standard multi-component quantitative analysis. With ferulic acid as a single marker, the contents of eight main active ingredients, including ferulic acid, senkyunolide I, senkyunolide H, coniferyl ferulate, E-ligustilide, E-butylidenephthalide, Z-ligustilide, and Z-butylidenephthalide, were simultaneously determined in 30 min by reliable relative correction factor. The overall chemical profiles of Angelica sinensis radix were compared by fingerprint similarity evaluation, the specific content level of each component was compared by simultaneous content determination of multiple components of a single standard, and the specific different components of Angelica sinensis radix before and after processing were analyzed by chemometrics. The established method was successfully applied to the quality evaluation of 44 batches of Angelica sinensis radix from 4 different origins and 45 batches of Angelica sinensis radix with different processing methods. This study proposed a simple, rapid, low-cost, and reliable quality comprehensive evaluation method for ASR from different origins and processing methods, which may be readily transferred and applied to other industries. [ABSTRACT FROM AUTHOR]

Summary: The fraudulent practice of beef adulteration is a growing concern, as it violates consumer rights. Electrical impedance spectroscopy (EIS) combined with machine learning has emerged as a widely used approach to identify low‐quality meat. Unlike traditional biochemical methods that require expensive instruments, complex sample preparation, and chemical reagents, EIS is a cost‐effective alternative. However, EIS data are susceptible to temperature fluctuations, requiring a waiting period under consistent temperature conditions for data stabilisation before measurements. This process becomes impractical when dealing with a large number of samples. To overcome this limitation, standardisation, normalisation, and smoothing methods were introduced in the meat quality detection based on EIS data. A recognition model for detecting carrageenan adulteration in beef was established. Under an inconsistent temperature condition, by applying the spectra pre‐processing methods to the prediction dataset, the model accuracy reached 84%, whereas the accuracy of the unprocessed prediction dataset dropped to 54%. This study demonstrates that acquiring EIS data under consistent temperature conditions is unnecessary if proper spectra pre‐processing methods are applied. By eliminating the waiting time for data stabilisation, this practical approach enhances the efficiency and accuracy of meat quality detection. [ABSTRACT FROM AUTHOR]

The industrial applications of the κ-carrageenases have been restricted by their poor thermostability. In this study, based on the folding free energy change (ΔΔG) and the flexibility analysis using molecular dynamics (MD) simulation for the alkaline κ-carrageenase KCgCD from Pseudoalteromonas porphyrae (WT), the mutant S190R was identified with improved thermostability. After incubation at 50 °C for 30 min, the residual activity of S190R was 63.7%, 25.7% higher than that of WT. The Tm values determined by differential scanning calorimetry were 66.2 °C and 64.4 °C for S190R and WT, respectively. The optimal temperature of S190R was 10 °C higher than that of WT. The κ-carrageenan hydrolysates produced by S190R showed higher xanthine oxidase inhibitory activity compared with the untreated κ-carrageenan. MD simulation analysis of S190R showed that the residues (V186–M194 and P196–G197) in F5 and the key residue R150 in F3 displayed the decreased flexibility, and residues of T169–N173 near the catalytic center displayed the increased flexibility. These changed flexibilities might be the reasons for the improved thermostability of mutant S190R. This study provides a useful rational design strategy of combination of ΔΔG calculation and MD simulation to improve the κ-carrageenase's thermostability for its better industrial applications. Key points: Mutant κ-carrageenase S190R is identified by rational design based on ΔΔG and MD simulation. Mutant κ-carrageenase S190R increases the thermostability. Mutant enzyme-treated κ-carrageenan exhibits high xanthine oxidase inhibitory activity. [ABSTRACT FROM AUTHOR]

The flavonoid naringenin is abundantly present in pomelo peels, and the unprocessed naringenin in wastes is not friendly for the environment once discarded directly. Fortunately, the hydroxylated product of eriodictyol from naringenin exhibits remarkable antioxidant and anticancer properties. The P450s was suggested promising for the bioconversion of the flavonoids, but less naturally existed P450s show hydroxylation activity to C3′ of the naringenin. By well analyzing the catalytic mechanism and the conformations of the naringenin in P450, we proposed that the intermediate Cmpd I ((porphyrin)Fe = O) is more reasonable as key conformation for the hydrolyzation, and the distance between C3′/C5′ of naringenin to the O atom of CmpdI determines the hydroxylating activity for the naringenin. Thus, the "flying kite model" that gradually drags the C-H bond of the substrate to the O atom of CmpdI was put forward for rational design. With ab initio design, we successfully endowed the self-sufficient P450-BM3 hydroxylic activity to naringenin and obtained mutant M5-5, with kcat, Km, and kcat/Km values of 230.45 min−1, 310.48 µM, and 0.742 min−1 µM−1, respectively. Furthermore, the mutant M4186 was screened with kcat/Km of 4.28-fold highly improved than the reported M13. The M4186 also exhibited 62.57% yield of eriodictyol, more suitable for the industrial application. This study provided a theoretical guide for the rational design of P450s to the nonnative compounds. Key points: •The compound I is proposed as the starting point for the rational design of the P450BM3 •"Flying kite model" is proposed based on the distance between O of Cmpd I and C3′/C5′ of naringenin •Mutant M15-5 with 1.6-fold of activity than M13 was obtained by ab initio modification [ABSTRACT FROM AUTHOR]

Fungal infection has become a major threat to crop loss and affects food safety. The waste water from agar processing industries extraction has a number of active substances, which could be further transformed by microorganisms to synthesize antifungal active substances. In this study, Bacillus subtilis was used to ferment the waste water from agar processing industries extraction to analyze the antifungal activity of the fermentation broth on Alternaria alternata and Alternaria spp. Results showed that 25% of the fermentation broth was the most effective in inhibited A. alternata and Alternaria spp., with fungal inhibition rates of 99.9% and 96.1%, respectively, and a minimum inhibitory concentration (MIC) was 0.156 μg/mL. Metabolomic analysis showed that flavonoid polyphenols such as coniferyl aldehyde, glycycoumarin, glycitin, and procyanidin A1 may enhance the inhibitory activity against the two pathogenic fungal strains. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that polyphenols involved in the biosynthesis pathways of isoflavonoid and phenylpropanoid were upregulated after fermentation. The laser confocal microscopy analyses and cell conductivity showed that the cytoplasm of fungi treated with fermentation broth was destroyed. This study provides a research basis for the development of new natural antifungal agents and rational use of seaweed agar waste. Key points: • Bacillus subtilis fermented waste water has antifungal activity • Bacillus subtilis could transform active substances in waste water • Waste water is a potential raw material for producing antifungal agents [ABSTRACT FROM AUTHOR]

The flavonoid naringenin is abundantly present in pomelo peels, and the unprocessed naringenin in wastes is not friendly for the environment once discarded directly. Fortunately, the hydroxylated product of eriodictyol from naringenin exhibits remarkable antioxidant and anticancer properties. The P450s was suggested promising for the bioconversion of the flavonoids, but less naturally existed P450s show hydroxylation activity to C3′ of the naringenin. By well analyzing the catalytic mechanism and the conformations of the naringenin in P450, we proposed that the intermediate Cmpd I ((porphyrin)Fe = O) is more reasonable as key conformation for the hydrolyzation, and the distance between C3′/C5′ of naringenin to the O atom of CmpdI determines the hydroxylating activity for the naringenin. Thus, the “flying kite model” that gradually drags the C-H bond of the substrate to the O atom of CmpdI was put forward for rational design. With ab initio design, we successfully endowed the self-sufficient P450-BM3 hydroxylic activity to naringenin and obtained mutant M5-5, with kcat, Km, and kcat/Km values of 230.45 min−1, 310.48 µM, and 0.742 min−1 µM−1, respectively. Furthermore, the mutant M4186 was screened with kcat/Km of 4.28-fold highly improved than the reported M13. The M4186 also exhibited 62.57% yield of eriodictyol, more suitable for the industrial application. This study provided a theoretical guide for the rational design of P450s to the nonnative compounds. Key points: •The compound I is proposed as the starting point for the rational design of the P450BM3 •“Flying kite model” is proposed based on the distance between O of Cmpd I and C3′/C5′ of naringenin •Mutant M15-5 with 1.6-fold of activity than M13 was obtained by ab initio modification [ABSTRACT FROM AUTHOR]

Fungal infection has become a major threat to crop loss and affects food safety. The waste water from agar processing industries extraction has a number of active substances, which could be further transformed by microorganisms to synthesize antifungal active substances. In this study, Bacillus subtilis was used to ferment the waste water from agar processing industries extraction to analyze the antifungal activity of the fermentation broth on Alternaria alternata and Alternaria spp. Results showed that 25% of the fermentation broth was the most effective in inhibited A. alternata and Alternaria spp., with fungal inhibition rates of 99.9% and 96.1%, respectively, and a minimum inhibitory concentration (MIC) was 0.156 μg/mL. Metabolomic analysis showed that flavonoid polyphenols such as coniferyl aldehyde, glycycoumarin, glycitin, and procyanidin A1 may enhance the inhibitory activity against the two pathogenic fungal strains. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that polyphenols involved in the biosynthesis pathways of isoflavonoid and phenylpropanoid were upregulated after fermentation. The laser confocal microscopy analyses and cell conductivity showed that the cytoplasm of fungi treated with fermentation broth was destroyed. This study provides a research basis for the development of new natural antifungal agents and rational use of seaweed agar waste. Key points: • Bacillus subtilis fermented waste water has antifungal activity • Bacillus subtilis could transform active substances in waste water • Waste water is a potential raw material for producing antifungal agents [ABSTRACT FROM AUTHOR]

Ecological forests are an important part of terrestrial ecosystems, are an important carbon sink and play a pivotal role in the global carbon cycle. At present, the comprehensive utilization of optical and radar data has broad application prospects in forest parameter extraction and biomass estimation. In this study, tree and topographic data of 354 plots in key nature reserves of Liaoning Province were used for biomass analysis. Remote sensing parameters were extracted from Landsat 8 OLI and Sentinel-1A radar data. Based on the strong correlation factors obtained via Pearson correlation analysis, a linear model, BP neural network model and PSO neural network model were used to simulate the biomass of the study area. The advantages of the three models were compared and analyzed, and the optimal model was selected to invert the biomass of Liaoning province. The results showed that 44 factors were correlated with forest biomass (p < 0.05), and 21 factors were significantly correlated with forest biomass (p < 0.01). The comparison between the prediction results of the three models and the real results shows that the PSO-improved neural network simulation results are the best, and the coefficient of determination is 0.7657. Through analysis, it is found that there is a nonlinear relationship between actual biomass and remote sensing data. Particle swarm optimization (PSO) can effectively solve the problem of low accuracy in traditional BP neural network models while maintaining a good training speed. The improved particle swarm model has good accuracy and speed and has broad application prospects in forest biomass inversion. [ABSTRACT FROM AUTHOR]

The quality of seaweed is greatly influenced by its harvest period. Hence, the development of efficient and precise analytical techniques for identifying the harvest period is significant from a practical standpoint. In this study, mid-infrared spectroscopy was utilized to perform quantitative analysis of nutritional components, evaluate the quality grades, and determine the harvest period of Porphyra haitanensis. While the outcomes of one-factor analysis of variance and correlation analysis indicated a general decrease in P. haitanensis quality with each subsequent harvest, the nutritional contents of samples obtained from the first and fifth harvest were similar, suggesting that the harvest period alone could not fully represent the quality of seaweed. To create discriminant models of the harvest period, decision tree, K-nearest neighbor, partial least squares-discriminant analysis, and adaptive boosting algorithms were adopted based on band integral areas and a small sample size (30 per harvest period, 6 periods in total). The adaptive boosting algorithm provided the most comprehensive results with regards to forecast accuracy (96.7%), macro precision (0.971), macro recall (0.965) and RMSE (0.183). The findings demonstrated that band integral areas of the mid-infrared spectroscopy not only provided quantitative information on the nutrients but also offered effective prediction variables for classification algorithms. Thus, the proposed method can serve as an essential instrument to evaluate the seaweed quality swiftly and precisely. [ABSTRACT FROM AUTHOR]

In the paper, a new one-dimensional (1-D) compound Sine chaotic system (CSCS) is first proposed. Then new chaotic maps are generated by the CSCS. And four novel generated maps are used for the illustration about the CSCS. Secondly, the results of performance analysis show that the four maps have large Lyapunov exponents and high complexity. Thirdly, a high-efficiency image encryption scheme is proposed by employing two of the four new produced chaotic maps. In the proposed encryption scheme, the simplest diffusion operation is used. And we use a variety of scrambling operations, such as Zigzag transform, Magic confusion and the row confusion. In addition, to increase key space and in order to improve the ability to resist two kinds of attacks, namely the known plaintext attack and the selected plaintext attack, the control parameters and the initial values of the two new chaotic systems are generated based on the SHA-256 function. Finally, compared to other schemes, simulation tests show that our scheme not only has higher security but also faster encryption speed. [ABSTRACT FROM AUTHOR]

Aiming at the problems of complex equations, low accuracy, and the strict measurement point layout requirements of the existing electric field integration method, a non-contact measurement method based on the inversion voltage of the near electric field is proposed. Firstly, the field source relationship is clarified, the connection between the spatial electric field and the voltage is derived, and a near-end electric field inversion method is proposed. Secondly, a three-dimensional simulation model of an overhead line is established using COMSOL finite element software, the three-dimensional spatial potential distribution of the overhead line is obtained, and the voltage is inverted and calculated. Finally, an overhead line simulation test platform was built, and MEMS electric field sensors were used for testing and verification. The results show that the maximum error of the three-phase voltage inversion of the proximal electric field measurement is 6.8%, and the error between the voltage obtained by the experimental inversion measurement and the reference voltage is less than 7.2%. The simulation and experimental results also verify the accuracy and feasibility of the inversion voltage of the proximal electric field. The results of this paper can lay a foundation for the practical application of small and miniaturized electric field sensors, and help in the construction and development of smart grids. [ABSTRACT FROM AUTHOR]

Objective The presence of red blood cell (RBC) irregular antibodies can severely jeopardize mother and child and bring trouble to the treatment of anemia. The aim of this study was to analyze the specificity of RBC irregular antibody in inpatients. Methods An analysis was performed on samples from patients with RBC irregular antibodies. Antibody screening positive samples were analyzed. Results Among the 778 cases of irregular antibody positive samples, 214 were from males and 564 from females. History of blood transfusion accounted for 13.1% of the total. Of the women, 96.8% had a pregnancy. A total of 131 antibodies were identified. The antibodies included 68 Rh systematic antibodies, 6 MNS systematic antibodies, 6 Lewis systematic antibodies, 2 Kidd systematic antibodies, 10 autoantibodies, and 39 antibodies of uncertain specificity. Conclusion Patients with blood transfusion or pregnancy history are prone to produce RBC irregular antibodies. [ABSTRACT FROM AUTHOR]

We describe a catalytic cascade sequence involving directed C(sp3)−H activation followed by β‐heteroatom elimination to generate a PdII(π‐alkene) intermediate that then undergoes redox‐neutral annulation with an ambiphilic aryl halide to access 5‐ and 6‐membered (hetero)cycles. Various alkyl C(sp3)−oxygen, nitrogen, and sulfur bonds can be selectively activated, and the annulation proceeds with high diastereoselectivity. The method enables modification of amino acids with good retention of enantiomeric excess, as well as σ‐bond ring‐opening/ring‐closing transfiguration of low‐strain heterocycles. Despite its mechanistic complexity, the method employs simple conditions and is operationally straightforward to perform. [ABSTRACT FROM AUTHOR]

We describe a catalytic cascade sequence involving directed C(sp3)−H activation followed by β‐heteroatom elimination to generate a PdII(π‐alkene) intermediate that then undergoes redox‐neutral annulation with an ambiphilic aryl halide to access 5‐ and 6‐membered (hetero)cycles. Various alkyl C(sp3)−oxygen, nitrogen, and sulfur bonds can be selectively activated, and the annulation proceeds with high diastereoselectivity. The method enables modification of amino acids with good retention of enantiomeric excess, as well as σ‐bond ring‐opening/ring‐closing transfiguration of low‐strain heterocycles. Despite its mechanistic complexity, the method employs simple conditions and is operationally straightforward to perform. [ABSTRACT FROM AUTHOR]

Astaxanthin is a valuable carotenoid and is used as antioxidant and health care. Phaffia rhodozyma is a potential strain for the biosynthesis of astaxanthin. The unclear metabolic characteristics of P. rhodozyma at different metabolic stages hinder astaxanthin's promotion. This study is conducted to investigate metabolite changes based on quadrupole time‐of‐flight mass spectrometry metabolomics method. The results showed that the downregulation of purine, pyrimidine, amino acid synthesis, and glycolytic pathways contributed to astaxanthin biosynthesis. Meanwhile, the upregulation of lipid metabolites contributed to astaxanthin accumulation. Therefore, the regulation strategies were proposed based on this. The addition of sodium orthovanadate inhibited the amino acid pathway to increase astaxanthin concentration by 19.2%. And the addition of melatonin promoted lipid metabolism to increase the astaxanthin concentration by 30.3%. It further confirmed that inhibition of amino acid metabolism and promotion of lipid metabolism were beneficial for astaxanthin biosynthesis of P. rhodozyma. It is helpful in understanding metabolic pathways affecting astaxanthin of P. rhodozyma and provides regulatory strategies for metabolism. Take‐away: Purine, pyrimidine, and amino acid pathways competed with the carotenoid pathway.Upregulation of lipid metabolism contributed to the carotenoid pathway.Regulators of amino acids and lipids increased astaxanthin by 19.2% and 30.3%. [ABSTRACT FROM AUTHOR]

Summary: Unscrupulous merchants would sell cheap, low‐nutrition formula milk powder as pasteurised milk, or use it as a raw material in dairy products, for the purpose of making a profit. Currently, biochemical methods are utilised to identify the type of processed milk, which could involve chemical reagents, sample preparation and costly instruments. This paper investigates the utility of electrical impedance spectroscopy (EIS) in distinguishing different types of processed milk. Ultra‐high temperature sterilised milk, pasteurised milk and formula milk powder were studied. The one‐factor analysis of variance revealed that milk type had a significant influence on electrical properties, whereas sensory analysis, pH and total soluble solids showed poor discrimination of milk type. Recognition models were developed using Support Vector Classification, Partial Least Squares‐Discriminant Analysis (PLS‐DA), Gaussian Naive Bayes and Random Forest (RF). The nested cross‐validation and the external validation set (N = 45) indicated the RF model had the highest predicting accuracy of 97.8%; whereas PLS‐DA had a misclassification rate of 33.3% on positive samples and was, therefore, unsuitable for the authentication. The results demonstrated that the EIS data was featured enough for a small sample modelling (N = 75), and the established method was simple, fast and effective for liquid food classification. [ABSTRACT FROM AUTHOR]

In this paper, a universal two-dimensional (2D) enhanced cosine coupled model (2D-ECCM) is first designed, which can construct new 2D chaotic systems using most of the existing two one-dimensional (1D) maps as the seed maps. And a novel 2D Logistic-sine coupled map (2D-NLSCM) and a new 2D cubic-tent coupled map (2D-NCTCM) are generated by using the 2D-ECCM, and their chaotic features are analyzed by bifurcation diagram, trajectory, Lyapunov exponent spectrum, etc. Performance analyses show that two new maps have better chaotic behaviors than some state-of-the-art 2D chaos. Then, using the 2D-NLSCM, an image adaptive encryption algorithm is further designed. We propose an adaptive scrambling method to scramble image pixels directly by combining the target image information, and a bidirectional-sequential diffusion method for image pixels diffusion. The image adaptive scrambling can change the pixel values while effectively scrambling the pixel positions. And the bidirectional-sequential diffusion can be achieved to diffuse a minor change of a pixel value in the original image to all pixels of the encryption image. Therefore, the proposed algorithm is closely related to the target image in the encryption process. Moreover, the key of the proposed encryption algorithm is updated through the hash function SHA-512, which further increases the security of the algorithm. Ultimately, simulation experiment shows that the designed encryption algorithm has superior encryption efficiency. Performance analysis results indicate that the designed encryption algorithm, with average information entropy of 7.9988 and average chi-square of 238.3495, can withstand a series of common cryptanalytic attacks. [ABSTRACT FROM AUTHOR]

Introduction: The aims of this study were to observe the therapeutic effect of platelet (PLT) transfusion and to analyze influencing factors for the sake of providing useful clues for improving the efficacy of PLT transfusion. Methods: Included in this study were patients who received PLT transfusion in the affiliated hospital of Nantong University. Patients' sex, age, height, weight, PLT transfusion status, and 20–24-h PLT count before and after PLT transfusion were collected to calculate the PLT corrected count increment values before and after PLT transfusion. Solid-phase red cell adherence assay was used to determine PLT antibody. Statistical analysis was performed using SPSS25.0 Software. Results: A total of 364 patients received 1,060 PLT transfusions, including 728 successful transfusions and 332 unsuccessful transfusions. When the patients were grouped according to different etiologies, significant differences in PLT transfusion effectiveness were observed between these groups (χ2 = 15.070, p < 0.05). Grouping of the 364 patients according to sex, blood type, and PLT transfusion frequency showed no significant difference in PLT transfusion refractoriness (PTR) between different age-groups and sexes (p > 0.05). With the number of PLT transfusions increasing, PTR increased gradually. PLT antibodies were detected of 364 patients, 67 of them were positive. Among them, 63 cases (94.02%) were positive for HLA class I antibody. Conclusion: To reduce PTR, multiple factors should be considered comprehensively when PLT transfusion therapy is to be implemented in clinical practice. PLT antibody is the main immune factor causing PTR. [ABSTRACT FROM AUTHOR]

Citrus is an important source of flavonoids in our daily diet. Citrus flavonoids have antioxidant, anticancer, anti‐inflammatory, and cardiovascular disease prevention functions. Studies have shown that some pharmaceutical values of flavonoids may be related to their binding to bitter taste receptors, thus activating downstream signal transduction pathways; however, the underlying mechanism has not been systematically elucidated. In this paper, the biosynthesis pathway and the absorption and metabolism of citrus flavonoids were briefly reviewed, and the relationship between flavonoid structure and bitter taste intensity was investigated. In addition, the pharmacological effects of bitter flavonoids and the activation of bitter taste receptors in combating various diseases were discussed. This review provides an important basis for the targeted design of citrus flavonoid structures to make them more biologically active and more attractive as powerful drugs for the effective treatment of chronic diseases such as obesity, asthma, and neurological diseases. [ABSTRACT FROM AUTHOR]

The processing of Traditional Chinese Medicine requires the appropriate parameters, while the specific chemical markers are still absent to obtain the optimized processing. In this study, we used vinegar‐baked Euphorbia kansui as a case to dissect the chemical markers for the baking process using untargeted metabolomics. The robust chemical markers were selected based on the three rules, correlation, significant difference, and controllability. All the differential features were categorized based on their mass defects. After the differential analysis, 310 differential compounds were screened out and could be mainly divided into six categories: diacylglycerols and triacylglycerols demonstrated increasing trends with the baking time in the discriminant model, while ingenane‐type diterpenes, jatrophane‐type diterpenes, fatty acid esters, and fatty acids had decreasing trends. It was unexpected to find that the diterpenes did not correlate with the baking time. Only very few compounds meet the three rules. They were validated with a high‐performance liquid chromatography method. Finally, only 13‐Hydroxy‐9,11‐octadecadienoic acid and its isomer 9‐Hydroxy‐10,12‐octadecadienoic acid could be used further to differentiate the commercial vinegar‐baked Euphorbia kansui. It would be of interest to evaluate whether these two compounds could be utilized as markers to control more processing methods in future studies. [ABSTRACT FROM AUTHOR]

Anthracnose disease caused by Colletotrichum spp. is a limiting factor in avocado production worldwide. In Taiwan, Colletotrichum spp. cause post-harvest disease on avocado and greatly reduce the shelf life of the fruit. The aim of this study was to identify the species causing avocado anthracnose in Taiwan and characterize their pathogenicity. In this study, mature avocado fruits with brown lesions were collected from 13 orchards in avocado production areas in Taiwan from 2008 to 2010 and from 2019 to 2020. Eighty-seven Colletotrichum isolates were isolated from the lesions of avocado fruits. Eighty-six isolates were assigned to the Colletotrichum gloeosporioides species complex according to the Apn2-Mat1-2 intergenic spacer and partial mating type (Mat1-2) gene (ApMat) sequence. A preliminary phylogenetic analysis based on ApMat sequences indicated that the 86 isolates formed four clades, C1 to C4. A multi-gene phylogeny based on partial actin, calmodulin, chitin synthase (CHS), GAPDH, ribosomal internal transcribed spacer, and beta-tubulin (TUB) sequences further confirmed the species in the four clades, namely Colletotrichum fructicola (C1), Colletotrichum siamense (C2 and C4), and Colletotrichum tropicale (C3). One isolate, Col-735, was identified to be Colletotrichum eriobotryae according to a phylogenetic tree constructed with the CHS, GAPDH, and TUB sequences. Pathogenicity tests on wounded 'Choquette' and 'Zhongpu green peel' avocado fruits showed the above four Colletotrichum species were pathogenic on these fruits. This is the first report studying Colletotrichum species and their pathogenicity on avocado in Taiwan, and C. eriobotryae is reported as an avocado fruit pathogen for the first time. [ABSTRACT FROM AUTHOR]

Rationale: Diterpene lactones (DL) in Andrographis paniculata (AP) are known as “natural antibiotics” for their excellent antibacterial activity. During mass spectrometry (MS) analysis, the hydroxyl groups in the AP DL skeleton are prone to neutral loss of H2O, producing high in‐source fragment peaks and affecting the characterization of these components. Methods: Mass tags were applied during the MS data acquisition step, and special adduct ion form was used to guide the data processing and characterization steps. Besides, the total number of characterized AP DLs significantly increased when combining the number of neutrally lost H2O from AP DLs, incorporating information on the diagnostic ions, and adopting molecular networks generated with the Global Natural Products Social Molecular Networking database. Results: Ninety‐nine DLs, comprising 6 monohydroxyl groups, 20 dihydroxyl groups, 27 trihydroxy groups, and 46 DLs with more than 3 hydroxyl groups, were characterized from AP. In addition, based on the characteristic fragments in the product ions (C3H4, Δm/z = 40.03 Da), it could be assumed that 90 DLs had the C19‐OH structure among the identified DLs. The current study provides a new approach for collecting, processing, and characterizing MS analysis of natural DLs prone to in‐source fragmentation. Conclusions: MS characterization of AP DLs was significantly improved, and many potential new compounds were identified in AP. This characterization provides new methods for the purification and identification of AP DLs. [ABSTRACT FROM AUTHOR]

A fluorescence quantitative detection method suitable for high-throughput screening of rhamnosidase catalytic activity on naringin was established. Detection of prunin at λex/λem = 360/450 nm was based on the fluorescence difference after heating under alkaline conditions. Detection of naringin at λex/λem = 325/400 nm was based on the difference in fluorescence in phosphate buffer. The method is suitable for prescreening many samples. A similar method can detect the fluorescence of hesperidin and hesperitin-7-o-glucoside, which provides a reference for the rapid detection of diglycosides and corresponding deglycosylated monoglycosides. [ABSTRACT FROM AUTHOR]

The effect of black tea powder on the antioxidant activity and gel characteristics of fish balls from silver carp were investigated after freezing storage for 7 days. The results show that black tea powder with different concentrations of 0.1%, 0.2% and 0.3% (w/w) could significantly increase the antioxidant activity of fish balls (p < 0.05). In particular, at the concentration of 0.3%, the antioxidant activity was the strongest among these samples, where the reducing power, DPPH, ABTS and OH free radical scavenging rate were up to 0.33, 57.93%, 89.24% and 50.64%, respectively. In addition, black tea powder at the level of 0.3% significantly increased the gel strength, hardness and chewiness while greatly reducing the whiteness of the fish balls (p < 0.05). ESEM observation found that the addition of black tea powder could promote the crosslinking of proteins and reduced the pore size of the gel network structure of the fish balls. The results suggest that black tea powder could be used as a natural antioxidant and gel texture enhancer in fish balls, which we found to be much related to the phenolic compounds of black tea powder. [ABSTRACT FROM AUTHOR]

At present, the image encryption algorithm based on the bit‐plane has the problem that the encryption speed and the encryption effect cannot be well balanced. To address the problem, an image layered scrambling encryption algorithm is proposed in this paper. First, a new one‐dimensional Cosine Logistic compound chaotic map (1DCLC) is proposed. Several characteristics of the new chaotic map are analyzed by using various measures, such as bifurcation diagram, Lyapunov exponent, sample entropy etc. And the results show that the novel chaotic map has a better chaotic performance. Second, based on the chaotic map, an image encryption algorithm is proposed. The algorithm first performs an XOR encryption operation on the image. Second, the layered scrambling is applied to the XOR encrypted image. Then the layered and scrambled image is recombined for the second XOR encryption operation. In particular, in the layered scrambling, not only can the position of the pixel be changed but also the value of the pixel can be modified, which improves the security of the algorithm. In addition, in order to defend against various plaintext attacks and increase the security of the overall algorithm, the Hash function is introduced to update the key of the proposed algorithm. Finally, the original algorithm is improved and the improved algorithm's ability to resist differential attacks is analyzed. The experimental simulation and security test results show that the proposed encryption algorithm has a comparable encryption effect and a faster encryption speed. [ABSTRACT FROM AUTHOR]

Among many modulation methods, strain engineering is often chosen for nanomaterials to produce tunable band gaps continuously. Inspired by the recently reported two-dimensional material PC3, we explore the tuning of strain on the spin-dependent transport properties of PC3 nanoribbons using the first-principle approach. Surprisingly, strain regulation achieves uninterrupted completely dual-spin polarization over a wide energy range near EF. Analysis reveals that the peculiar transmission spectra arise from the interesting evolution of the band structure, in which strain induces bands to shift and broaden/flatten. This results in triggering the transition of PC3NRs from bandgap-tunable bipolar magnetic semiconductors to spin-gapless semiconductors to ferromagnetic metals or half-metal magnets. Their unique performance demonstrates great potential in spintronics, and our study is expected to provide ideas and theoretical support for the design and application of novel PC3-based spintronic devices in the future. [ABSTRACT FROM AUTHOR]

In order to clarify the differences in the aroma quality and its material basis between Tieguanyin tea and Baiyaqilan tea, the overall aroma profiles and the key aroma components of the two teas were analyzed by quantitative descriptive analysis (QDA), gas chromatography-mass spectrometry-olfactometry (GC-MS-O), and odor activity value (OAV). Except for the intensity of grassy note, the intensities of floral, sweet, caramel and roasted notes of Tieguanyin were significantly lower than those of Baiyaqilan tea (p<0.05). The total contents of the volatile compounds from the aqueous solutions of Tieguanyin and Baiyaqilan teas were 19 314.76 μg/L and 5 685.77 μg/L, respectively. GC-MS-O combined with OAV analysis showed that the key aroma-active components of Tieguanyin mainly included indole, cis-iasmine lactone, benzeneacetaldehyde, cis-jasmone and trans-nerolidol. The key aroma-active components of Baiyaqilan tea mainly included hotrienol, geraniol, cis-iasmine lactone, β-cyclocitral, trans-α-ionone, cis-jasmone, 3-ethyl-2,5-dimethyl-pyrazine, indole and safranal. The above results clarified the main aroma components accounting for the difference in aroma quality between Tieguanyin tea and Baiyaqilan tea, which provides a data reference for the precise control of tea quality. [ABSTRACT FROM AUTHOR]

Purpose: The microbial community in the pit mud correlated closely with the quality of the final product of Chinese strong-flavored Baijiu (CSFB). However, environmental conditions and brewing processes can vary by region and distilleries. This may lead to differences in microbial composition and function in pit mud. Therefore, revealing the features of the pit mud microbial community structure and functions of different distilleries will provide key information for understanding the diversity and difference of microbes in the brewing of CSFB, which will be beneficial for the improvement of the quality of pit mud and CSFB in the future. Methods and results: Illumina MiSeq sequencing of 16S rRNA gene amplicons was used to analyze the similarities and differences in microbial community structure and function in pit muds of different distilleries located in Shihezi (Xinjiang), Xiangyang (Hubei), and Yibin (Sichuan). At the genus level, Clostridium, Lactobacillus, Aminobacterium, Petrimonas, Syntrophomonas, Methanoculleus, Syntrophaceticus, Sedimentibacter, Caloramator, Ruminococcus, Bacillus, Methanosarcina, and Garciella were the dominated genera of pit muds. There were great differences in the composition of microorganisms in pit muds used by different distilleries. The significantly enriched prokaryotic microbiotas of pit muds collected in the distilleries of Xiangyang were mainly affiliated with Bacillus, Lactobacillus, and Croceifilum, and the relative abundance of methanogens, such as Methanomicrobia and Methanobacteria, were only significantly enriched in the pit mud collected from the distilleries of Yibin (P < 0.05). Functional analysis indicated that the difference of microbial composition in pit mud will further lead to significant differences in various metabolic functions. Conclusion: The compositions and functions of dominant microorganisms in pit mud used for the production of CSFB by different enterprises across regions in China were greatly different, and there was a close relationship between the compositions and functions of microorganisms in pit mud. Therefore, it may be an effective method to improve CSFB fermentation processes by directionally regulating the microbial community functions of pit mud using specific strains. [ABSTRACT FROM AUTHOR]

Compared with traditional magnetic approaches, electrical modulation of spin-polarized current can greatly reduce the energy consumption and scale of nanodevices and improve their operating speed, which has become a promising research field in spintronics. Motivated by the latest reported novel two-dimensional material β-SiC7, we employ first-principles calculations to investigate its spin-dependent electron transport with diverse edge configurations. By introducing a gate voltage, the three-terminal device can not only switch between spin-unpolarized and fully spin-polarized states, but also easily change the polarization direction, behaving as an excellent electrically modulated reversible dual-spin filter. Surprisingly, an arbitrary proportion of spin-up and spin-down electron numbers is achieved, enabling precise control of spin polarization. Analysis reveals that it is attributed to the peculiar transmission spectrum, where two broad peaks with opposite spins are located around the Fermi level and respond differently to gate voltage. They belong to the spatially separated edge states originating from the p orbitals of the edge atoms. This feature is robust to different edge configurations of β-SiC7 nanoribbons, indicating that this may be an intrinsic property of such systems, showing great potential for applications. [ABSTRACT FROM AUTHOR]

Background: Dandelion is an herb with high nutritional and medicinal values, which has been listed in Chinese Pharmacopeia, European Pharmacopoeia and British Pharmacopoeia, gaining increasing acceptance around the world. However, the current quality control of dandelion is lagging behind. Only in Chinese Pharmacopeia, cichoric acid is used as a marker compound for its quality evaluation, whereas, it can not comprehensively reflect the bioactivity of dandelion. Methods: This study developed a strategy by integrating chemometrics with in silico pharmacology to reveal the bioactive markers of dandelion for its quality control. Firstly, the major chemicals in dandelion were characterized using HPLC-DAD-MS/MS, and the corresponding antioxidant and anti-inflammatory activities were evaluated in vitro. Subsequently, the active components were screened by relating the chemicals and bioactivity of dandelion via grey relational assay and partial least squares regression analysis. The potential active components were then subjected to a validation for their activities. Moreover, in silico pharmacology was utilized to evaluate the contribution of active components to efficacy. Results: A total of 22 phenolic compounds were characterized. Among them, cichoric acid, caffeic acid and luteolin were identified as quality markers owing to their good correlations with the bioactivities of dandelion. These three markers were quantified in frequently-used dandelion species, viz. Taraxacum mongolicum Hand.-Mazz. (TAM) and T. officinale F. H. Wigg. (TAO). TAM, with acceptably higher content of cichoric acid and caffeic acid, showed better antioxidant activity than TAO. While TAO included higher content of luteolin, presenting slightly more effective in anti-inflammation. Conclusion: An useful strategy for the quality marker discovery was successfully designed. And the results provided more knowledge for the quality evaluation of dandelion. [ABSTRACT FROM AUTHOR]

Marine bacterium Microbulbifer sp. ALW1 was revealed to be able to effectively degrade Laminaria japonica thallus fragments into fine particles. Polysaccharide substrate specificity analysis indicated that ALW1 could produce extracellular alginate lyase, laminarinase, fucoidanase and cellulase. Based on alignment of the 16 S rRNA sequence with other reference relatives, ALW1 showed the closest relationship with Microbulbifer aggregans CCB-MM1T. The cell morphology and some basic physiological and biochemical parameters of ALW1 cells were characterised. ALW1 is a Gram-negative, rod- or oval-shaped, non-spore-forming and non-motile bacterium. The DNA–DNA relatedness values of ALW1 with type strains of M. gwangyangensis (JCM 17,800), M. aggregans (JCM 31,875), M. maritimus (JCM 12,187), M. okinawensis (JCM 16,147) and M. rhizosphaerae (DSM 28,920) were 28.9%, 43.3%, 41.2%, 35.4% and 45.6%, respectively. The major cell wall sugars of ALW1 were determined to be ribose and galactose, which differed from other closely related species. These characteristics indicated that ALW1 could be assigned to a separate species of the genus Microbulbifer. The complete genome of ALW1 contained one circular chromosome with 4,682,287 bp and a GC content of 56.86%. The putative encoded proteins were categorised based on their functional annotations. Phenotypic, physiological, biochemical and genomic characterisation will provide insights into the many potential industrial applications of Microbulbifer sp. ALW1. Key points. Key points: Microbulbifer sp. ALW1 has Laminaria japonica degradation capability. Genomic information of strain ALW1 is useful for analysing the polysaccharides degradation process. Microbulbifer sp. ALW1 could be potentially applied in producing functional materials. [ABSTRACT FROM AUTHOR]

In this study, physicochemical and structural properties of microcrystaline cellulose (MCC) from pomelo fruitlets using different drying methods were analyzed and compared with commercial MCC. The results showed that oil‐holding capacity (OHC), water‐holding capacity (WHC), swelling properties, cholesterol adsorption capacity, and pancreatic lipase inhibition of MCC from pomelo fruitlets especially using freeze drying were higher than those of commercial MCC (p <.05), indicating their better application properties in food processing and functional activity in gastrointestinal health. Through freeze drying, the decreased particle size and crystallinity were much related with its better OHC, WHC, swelling properties, and cholesterol adsorption capacity when compared to that using hot‐air drying. The reduction effect of freeze‐drying on thermal stability of MCC might be caused by the decreased crystallinity. Overall, MCC from pomelo fruitlets especially with freeze‐drying had higher OHC, hydration property, and potential hypolipidemic activity, suggesting its potential applications in pharmaceuticals and food industry. Practical applications: This study investigated physicochemical and structural properties of MCC from pomelo fruitlets using different drying methods and compared it with those of commercialized MCC. It was suggested that MCC from pomelo fruitlets especially with freeze‐drying had higher OHC, hydration property, and potential hypolipidemic activity than those of commercial MCC. The results can provide comprehensive evaluation on high‐value application of pomelo fruitlets to produce MCC with desirable properties. [ABSTRACT FROM AUTHOR]

Phosphate is widely used in surimi products to improve the gel properties. However, excess addition of phosphate occurs, which can harm the consumer's health. This study aimed to evaluate the effects of agar gum and fucoidan on maintaining the gel properties of surimi products instead of phosphate. Interestingly, our results showed that 0.125% of agar gum and fucoidan to replace phosphate could enhance water‐holding capacity and maintain gel strength and textual properties of surimi products well. Especially at frozen storage for 1 year, 0.125% of agar gum reduced the expressible moisture content of surimi products by around 10% (p <.05). Sensory evaluation showed that 0.125% of agar gum and fucoidan instead of phosphate can improve tissue and fondness of surimi products in refrigerated storage for 24 h but not in frozen storage for 1 year. The addition of agar gum and fucoidan at a high concentration >0.50% increased the WHC, but significantly decreased gel strength and springiness of surimi products (p <.05). Particularly, 1.00% of agar gum and fucoidan reduced gel strength by around 20% (p <.05). It might be due to the destruction of the gel network structure of surimi protein following the excess addition of these polysaccharides. It can be concluded that 0.125% of agar gum and fucoidan can replace phosphate to develop high‐quality surimi products, and excessive addition of them have negative effects. [ABSTRACT FROM AUTHOR]

The inhibition of aldose reductase is an effective strategy to alleviate symptoms of diabetic complications. The p‐coumaric acid ethyl ester (p‐CAEE) was taken as an example to investigate the inhibition of aldose reductase from p‐coumaric acid derivations. The results showed p‐CAEE strongly inhibited aldose reductase with the half inhibitory concentration of 1.92 μM, following the noncompetitive manner with a Ki value of 0.94 μM. After binding with p‐CAEE, the enzyme showed increased β‐sheet content, and the α‐helix content, random coil content, and intrinsic fluorescence strength decreased. p‐CAEE bonded with aldose reductase at the anionic, hydrophobic, and selective pockets of the enzyme, via hydrogen bond and hydrophobic interactions with Thr113, Cys80, Trp111, and Leu300, etc. The strong inhibition was related to the high oil–water partition coefficient and special esterify group. This study provides new information to develop aldose reductase inhibitors from p‐coumaric acid derivations. Practical applications: Inhibition of aldose reductase is an effective strategy to alleviate and control the symptoms of diabetic complications. In this study, it has been shown that p‐coumaric acid ethyl ester could strongly inhibit the aldose reductase. In addition, the inhibition of aldose reductase was been correlated with structures and oil–water partition coefficients of p‐coumaric acid derivatives. It provides a theoretical basis for the development of effective aldose reductase inhibitors. [ABSTRACT FROM AUTHOR]