Lignicolous Freshwater Fungi from Plateau Lakes in China (I): Morphological and Phylogenetic Analyses Reveal Eight Species of Lentitheciaceae, Including New Genus, New Species and New Records.

During the investigation of lignicolous freshwater fungi in plateau lakes in Yunnan Province, China, eight Lentitheciaceae species were collected from five lakes viz. Luguhu, Qiluhu, Xingyunhu, Cibihu, and Xihu lake. Based on morphological characters and phylogenetic analysis of combined ITS, LSU, SSU, and tef 1-α sequence data, a new genus Paralentithecium, two new species (Paralentithecium suae, and Setoseptoria suae), three new records (Halobyssothecium phragmitis, H. unicellulare, and Lentithecium yunnanensis) and three known species viz. Halobyssothecium aquifusiforme, Lentithecium pseudoclioninum, and Setoseptoria bambusae are reported.

Additions to the Genus Helicosporium (Tubeufiaceae, Tubeufiales) from China with an Identification Key for Helicosporium Taxa.

Helicosporous hyphomycetes is a group of filamentous fungi that shows promising application prospects in metabolizing bioactive natural compounds. During a study of helicosporous fungi in China, six new helicosporous taxa were collected and isolated from decaying wood in Guangxi Zhuang Autonomous Region, China. Morphological comparisons with multi-gene phylogenetic analyses revealed that these six taxa belong to Helicosporium (Tubeufiaceae, Tubeufiales), and they were recognized as three novel species and were named Helicosporium liuzhouense, H. multidentatum, and H. nanningense. Detailed descriptions and illustrations of the newly discovered taxa and comparisons with similar fungi are provided. In addition, a list and a key to accepted Helicosporium species are provided.

Qualitative and quantitative analysis of four benzimidazole residues in food by surface-enhanced Raman spectroscopy combined with chemometrics.

In this study, surface-enhanced Raman spectroscopy (SERS) combined with chemometric methods were developed for qualitative and quantitative analysis of four benzimidazole (BMZs) residues in corn. Sulfhydryl functionalized Fe3O4@SiO2@Ag-SH magnetic SERS substrates were prepared to obtain the SERS spectra of four BMZs for chemometric analysis. The partial least squares regression discrimination analysis (PLS-DA) model performed best, with a recall rate upwards 99.17%, and could successfully distinguish four BMZs. Under the support vector machine regression (SVR) model, the detection limits of carbendazim, benomyl, thiophanate-methyl and thiabendazole were 0.055 mg/L, 0.056 mg/L, 0.067 mg/L and 0.093 mg/L, respectively; the average recovery was in the range of 85.6%-107.5%. Furthermore, the method verified by HPLC, and the results showed that there was no significant difference between two methods (p > 0.05). Therefore, the strategy based on SERS coupling chemometrics can be served as a promising tool for rapid determination of BMZs residues in food.

A multi-block data approach to assessing beef quality: ComDim analysis of hyperspectral imaging, 1H NMR, electronic nose and quality parameters data.

Several factors affect the quality of beef. In the field of chemometrics, multi-block data analysis methods are useful for examining multiple sources of information from a sample. This study focuses on the application of ComDim, a multi-block data analysis method, to evaluate beef from different parts of hyperspectral spectrum and image texture information, 1H NMR fingerprints, quality parameters and electronic nose. Compared to principal component analysis (PCA) methods based on low-level data fusion, ComDim is more efficient and powerful, because it reveals the relationships between the methods and techniques studied, as well as the variability of beef quality across multiple metrics. The quality and metabolite composition of beef tenderloin and hindquarters were differentiated, with low L* value and high shear tenderloin distinguished from hindquarters with opposite characteristics. The proposed strategy demonstrates that ComDim approach can be used to characterize samples when different techniques describe the same set of samples.

Polysaccharide-addition order regulates sonicated egg white peptide stabilized nanoemulsions and ß-carotene digestion in vitro.

In this paper, the effects of the polysaccharide-addition order (before and after homogenisation) on the stability of nanoemulsion stabilised by sonicated egg white peptides and the in vitro digestive behaviour of loaded ß-carotene were investigated. The pyrene fluorescence results showed that the concentration of micelles formed by flaxseed gum (FG) in complex with peptides was significantly higher than that of peach gum (PG). The order of polysaccharide-addition affected the emulsion properties and stability; adding polysaccharides before homogenisation led to protein bridging flocculation, low polysaccharide coverage and a higher interfacial adsorbed protein content of the emulsion. PG enhanced potential spatial resistance and electrostatic repulsion, effectively prevented emulsion flocculation and improved electrostatic stability. After homogenisation, FG was added to emulsions to improve environmental stability, including ionic, temperature and storage stability. Due to the viscosity of polysaccharides and the formed polysaccharide-protein-lipid aggregates, the increasing degree of bridging flocculation promoted the prominent of apparent viscosity, and the G' and G'' exhibited a frequency-dependent increase. The polysaccharide type and mode changed the surface loading charge and droplet interface thickness, delayed the destruction of the droplet structure by protease, and slowed the release of ß-carotene to form micelles. In this study, a stable emulsion system and an efficient emulsion transport system for bioactive substances were obtained by regulating polysaccharides adding order, which is significant for constructing an efficient food emulsion delivery system.

Crop pest image classification based on improved densely connected convolutional network.

Introduction: Crop pests have a great impact on the quality and yield of crops. The use of deep learning for the identification of crop pests is important for crop precise management. Methods: To address the lack of data set and poor classification accuracy in current pest research, a large-scale pest data set named HQIP102 is built and the pest identification model named MADN is proposed. There are some problems with the IP102 large crop pest dataset, such as some pest categories are wrong and pest subjects are missing from the images. In this study, the IP102 data set was carefully filtered to obtain the HQIP102 data set, which contains 47,393 images of 102 pest classes on eight crops. The MADN model improves the representation capability of DenseNet in three aspects. Firstly, the Selective Kernel unit is introduced into the DenseNet model, which can adaptively adjust the size of the receptive field according to the input and capture target objects of different sizes more effectively. Secondly, in order to make the features obey a stable distribution, the Representative Batch Normalization module is used in the DenseNet model. In addition, adaptive selection of whether to activate neurons can improve the performance of the network, for which the ACON activation function is used in the DenseNet model. Finally, the MADN model is constituted by ensemble learning. Results: Experimental results show that MADN achieved an accuracy and F1Score of 75.28% and 65.46% on the HQIP102 data set, an improvement of 5.17 percentage points and 5.20 percentage points compared to the pre-improvement DenseNet-121. Compared with ResNet-101, the accuracy and F1Score of MADN model improved by 10.48 percentage points and 10.56 percentage points, while the parameters size decreased by 35.37%. Deploying models to cloud servers with mobile application provides help in securing crop yield and quality.

Bayesian Fusion Model Enhanced Codfish Classification Using Near Infrared and Raman Spectrum.

In this study, a Bayesian-based decision fusion technique was developed for the first time to quickly and non-destructively identify codfish using near infrared (NIRS) and Raman spectroscopy (RS). NIRS and RS spectra from 320 codfish samples were collected, and separate partial least squares discriminant analysis (PLS-DA) models were developed to establish the relationship between the raw data and cod identity for each spectral technique. Three decision fusion methods: decision fusion, data layer or feature layer, were tested and compared. The decision fusion model based on the Bayesian algorithm (NIRS-RS-B) was developed on the optimal discrimination features of NIRS and RS data (NIRS-RS) extracted by the PLS-DA method whereas the other fusion models followed conventional, non-Bayesian approaches. The Bayesian model showed enhanced classification metrics (92% sensitivity, 98% specificity, 98% accuracy) that were significantly superior to those demonstrated by any of other two spectroscopic methods (NIRS, RS) and the two data fusion methods (data layer fused, NIRS-RS-D, or feature layer fused, NIRS-RS-F). This novel proposed approach can provide an alternative classification for codfish and potentially other food speciation cases.

The relationship between acylation degree and gelling property of NaOH-induced egg white gel: Efficient is better?

In this study, succinic anhydride (SA) and octenyl succinic anhydride (OSA) were used to modify the egg white protein (EWP), and acylated EWP was further prepared as a gel by adding NaOH and heat modification. The results showed that the acylation degree for the SA- and OSA-added groups reached 57.68% and 26.95%, respectively, and the average size, the absolute value of ζ-potential, increased significantly with SA and OSA addition, indicating that acylation improved the stability of EWP solution. Furthermore, the surface hydrophobicity increased for the SA-added group while decreasing for the OSA-added group, and the acylation process exposed the flexibility part of the protein molecule. Acylated EWP prepared gel (EWG) showed a translucent and slightly yellow appearance (except for the sol state of the OSA-added 1:50 group), the gel strength, water-holding capacity and rheological properties for SA-added EWG were remarkably reduced while OSA-added EWG improved apparently. Intermolecular forces analysis indicated that the addition of SA promoted the formation of disulfide bonds and strengthened proteins interactions while adding OSA weakened the interactions. Microstructural observations revealed a rougher gel network structure and weaker protein cross-linking in the gel prepared after the acylation of proteins. However, the high efficiency of SA and promotion of protein-molecule interactions were unable to counteract the negative effect of SA on the extension of the gel network structure, and the interaction between OSA expanded the formation of the gel network structure.

Three New Species, Two New Records and Four New Collections of Tubeufiaceae from Thailand and China.

Tubeufiaceae, a cosmopolitan family with a worldwide distribution, is mostly reported as saprobic on decaying woody materials from both aquatic and terrestrial habitats. The family is commonly found as helicosporous hyphomycetes, while some are chlamydosporous and phragmosporous. In this study, thirteen helicosporous hyphomycetes were collected from Thailand and China. The phylogenetic analyses of combined ITS, LSU, TEF1-α, and RPB2 sequence data placed them in Dematiohelicomyces, Helicoma, Helicotruncatum, Neohelicosporium, Parahelicomyces, and Tubeufia within Tubeufiaceae. Three new species, Tubeufia cocois, Parahelicomyces chiangmaiensis, and Neohelicosporium bambusicola, one new host record, Tubeufia laxispora, and one new geographic record, T. longihelicospora, are introduced based on both morphological characteristics and phylogenetic analyses. In addition, Dematiohelicomyces helicosporus, Helicoma guttulatum, Helicotruncatum palmigenum, and Tubeufia cylindrothecia are described with detailed descriptions and color photo plates.

Facile Synthesis of Molecularly Imprinted Ratiometric Fluorescence Sensor for Ciguatoxin P-CTX-3C Detection in Fish.

Ciguatoxin (CTX) detection methods are essential due to the serious hazard that bioaccumulation in fish and transmission along the food chain poses to human health. We report the rapid and simple development of a dual-emitting, molecularly imprinted, ratiometric fluorescence sensor (MIPs@BCDs/RCDs@SiO2) to detect ciguatoxin P-CTX-3C with high sensitivity and selectivity. The sensor was fabricated via sol-gel polymerization using monensin as the fragmentary dummy template molecule, blue carbon dots (BCDs) as the response signal, and red carbon dots (RCDs) as the reference signal. The fluorescence emission of BCDs was selectively quenched in the presence of P-CTX-3C, leading to a favorable linear correlation between the fluorescence intensity ratio (I440/I675) and the P-CTX-3C concentration in the range of 0.001-1 ng/mL with a lower detection limit of 3.3 × 10-4 ng/mL. According to LC-MS measurement results, the proposed sensor can rapidly detect ciguatoxin P-CTX-3C in coral reef fish samples with satisfactory recoveries and standard deviations. This study provides a promising strategy for rapid trace analysis of marine toxins and other macromolecular pollutants in complex matrices.

One New Species and Two New Host Records of Apiospora from Bamboo and Maize in Northern Thailand with Thirteen New Combinations.

The genus Apiospora is known as a cosmopolitan genus, found across various substrates. In this study, four Apiospora taxa were obtained from the decaying stems of bamboo and maize in northern Thailand. Apiospora collections were compared with known species based on the morphological characteristics and the DNA sequence data of internal transcribed spacer (ITS), the partial large subunit nuclear rDNA (LSU), the translation elongation factor 1-alpha gene (TEF1-α) and beta-tubulins (TUB2). Apiospora chiangraiense sp. nov. and two new host records (Ap. intestini and Ap. rasikravindra) are introduced here based on the morphological characteristics and multi-locus analyses. Additionally, thirteen species previously identified as Arthrinium are introduced as new combinations in Apiospora, viz., Ap. acutiapica, Ap. bambusicola, Ap. biserialis, Ap. cordylines, Ap. cyclobalanopsidis, Ap. euphorbiae, Ap. gelatinosa, Ap. locuta-pollinis, Ap. minutispora, Ap. pseudorasikravindrae, Ap. septate, Ap. setariae and Ap. sorghi.

Rapid Identification of Rainbow Trout Adulteration in Atlantic Salmon by Raman Spectroscopy Combined with Machine Learning.

This study intends to evaluate the utilization potential of the combined Raman spectroscopy and machine learning approach to quickly identify the rainbow trout adulteration in Atlantic salmon. The adulterated samples contained various concentrations (0-100% w/w at 10% intervals) of rainbow trout mixed into Atlantic salmon. Spectral preprocessing methods, such as first derivative, second derivative, multiple scattering correction (MSC), and standard normal variate, were employed. Unsupervised algorithms, such as recursive feature elimination, genetic algorithm (GA), and simulated annealing, and supervised K-means clustering (KM) algorithm were used for selecting important spectral bands to reduce the spectral complexity and improve the model stability. Finally, the performances of various machine learning models, including linear regression, nonlinear regression, regression tree, and rule-based models, were verified and compared. The results denoted that the developed GA-KM-Cubist machine learning model achieved satisfactory results based on MSC preprocessing. The determination coefficient (R2) and root mean square error of prediction sets (RMSEP) in the test sets were 0.87 and 10.93, respectively. These results indicate that Raman spectroscopy can be used as an effective Atlantic salmon adulteration identification method; further, the developed model can be used for quantitatively analyzing the rainbow trout adulteration in Atlantic salmon.

A novel surface plasmon resonance sensor based on a functionalized graphene oxide/molecular-imprinted polymer composite for chiral recognition of l-tryptophan.

Herein, a novel surface plasmon resonance (SPR) sensor based on a functionalized graphene oxide (GO)/molecular-imprinted polymer composite was developed for the chiral recognition of l-tryptophan (l-Trp). The composite's recognition element was prepared via a facile and green synthesis approach using polydopamine as both a reducer of GO and a functional monomer as well as a cross-linker for molecular imprinting. The composite was characterized via Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. After attaching the composite onto the gold surface of an SPR chip, the sensor was characterized using contact-angle measurements. The sensor exhibited excellent selectivity and chiral recognition for the template (i.e., l-Trp). Density functional theory computations showed that the difference in hydrogen bonding between the composite element and l-Trp and d-Trp played an important role in chiral recognition.

Synthesis and Application of Novel Magnetic Ion-Imprinted Polymers for Selective Solid Phase Extraction of Cadmium (II).

Ion-imprinted polymers (IIPs) have received much attention in the fields of separation and purification. Nevertheless, selectivity of IIPs for trace target ions in complicated matrix remains a challenge. In this work, a cadmium magnetic ion-imprinted polymer (MIIP) was synthesized via surface imprinting, using methacrylic acid and acrylamide as dual functional monomers, vinyltrimethoxysilane as ligand, Fe3O4@SiO2 as support, azodiisobutyronitrile as initiator, and ethylene glycol dimethacrylate as crosslinker. The MIIP was characterized by transmission electron microscopy, infrared spectroscopy, thermal gravimetric analysis, and a vibrating sample magnetometer. The maximum adsorption capacities of the MIIP and magnetic non-imprinted polymer for Cd(II) were 46.8 and 14.7 mg·g-1, respectively. The selectivity factors of Pb(II), Cu(II), and Ni(II) were 3.17, 2.97, and 2.57, respectively, which were greater than 1. The adsorption behavior of Cd(II) followed the Freundlich isotherm and a pseudo second order model. The MIIP was successfully used for the selective extraction and determination of trace Cd(II) in representative rice samples. The limit of detection and recovery of the method was 0.05 µg·L-1 and 80⁻103%, respectively, with a relative standard deviation less than 4.8%. This study shows that MIIP provides an attractive strategy for heavy metal detection.

Polychlorinated biphenyl quinone metabolites lead to oxidative stress in HepG2 cells and the protective role of dihydrolipoic acid.

Parent polychlorinated biphenyls (PCBs) have been shown to induce cellular oxidative stress. However, the effects of PCB active metabolites have not been extensively investigated. Parent PCBs are first converted to hydroquinone metabolites via cytochrome P-450-catalyzed hydroxylation, and the hydroquinone metabolites are then further oxidized into the corresponding quinone metabolites. Quinones are responsible for a wide range of toxic effects because of their high reactivity. Previous studies have suggested that reactive oxygen species (ROS) play important roles in multiple toxic mechanisms. In this context, the present study was undertaken to investigate oxidative stress resulting from treatment with PCB quinones in HepG2 cells. The protective effects resulting from co-administration of dihydrolipoic acid (DH-LA) were also investigated. We have found that exposure to PCB quinones leads to: (1) a decrease in cell viability; (2) an increase in both the total ROS production and superoxide production; (3) only 3Cl-PCBQ caused significant increase in the thiobarbituric acid reactive substances (TBARS) level; (4) an increase in SOD activity and a decrease in catalase activity; and (5) a decrease in GST activity and GSH level. We have also found that quinones possessing a higher number of chlorine atoms on the quinone ring display a greater activity and that DH-LA is an effective protective agent as it diminishes PCB quinone-induced cellular oxidative stress.

Polychlorinated biphenyls and their different level metabolites as inhibitors of glutathione S-transferase isoenzymes.

Research on the effects of polychlorinated biphenyl (PCB) toxicity tends to focus on commercial PCB congeners and parent PCBs themselves. However, studies have suggested that PCB metabolites may be more interesting than the parent compounds because of their high reactivity. As a key metabolic enzyme, glutathione S-transferases (GSTs) are responsible for detoxification by catalyzing the conjugation reaction of glutathione (GSH) to xenobiotics. Inhibition of GST activity indicates reduced detoxification ability. We investigated the inhibition of chicken liver GSTs by parent PCBs and their metabolites and observed dose-dependent inhibition in vitro; inhibitory efficiency declined in the order GSH-conjugate > mono-hydroxyl ≈ quinone ≈ hydroquinone > parent PCB. Structure-inhibitory activity relationship studies indicated that with the inhibitory activity greatly increases with the number of GSH moieties or chlorine substituents on the quinone ring. However, no significant linear relationship was observed for chlorine pattern changes on the phenyl ring. The reversibility of PCB metabolite inhibition of GSTs is discussed. PCB mono-hydroxyl, hydroquinone and quinone forms showed irreversible inhibition of GSTs, which suggests a mechanism involving covalent binding to cysteine residues in the GST active site. PCB glutathionyl conjugates showed reversible GST inhibition, implying non-covalent binding. Furthermore, reactive oxygen species did not significantly affect GST activity.

Molecular characterization and expression analysis of caveolin-1 in pig tissues.

Members of the caveolin family played important roles during fundamental cellular processes, such as regulation of cell morphology, migration, and gene expression in muscle cells. In this study, caveolin-1 (Cav-1), one of the caveolins, was identified from longissimus dorsi muscle of Large Yorkshire pig and Chinese indigenous Lantang pig based on the results of mRNA differential display analysis. The deduced amino acids sequence of the porcine Cav-1 contained a caveolin domain, and was very conservative among different species. The Cav-1 mRNA was widely expressed in the eight tissues in this study, including heart, liver, kidney, encephalon, spleen, lung, longissimus dorsi muscle, and back fat, and the highest expression quantity was found in back fat of the two pig breeds. The expression quantity of porcine Cav-1 in back fat and longissimus dorsi muscle of Lantang pig was significantly higher than that of Large Yorkshire (P<0.01, and P<0.05, respectively). These results suggested that the Cav-1 might be a candidate gene for carcass traits, and might provide valuable information for understanding the mechanism of caveolae signaling in fat deposition by using the animal model of pig.

[Cloning and expression of the pig fast skeletal muscle troponin C gene].

A pig skeletal muscle expressed sequence tag (EST, accession number BM083186) was found to encode amino acid sequences with high homology to human TNNC2. In silico cloning obtained a 843 bp sequence which we named pig fast skeletal troponin C gene (TNNC2). The open reading frame of TNNC2 was between nucleotides 201 - 683, and was confirmed by RT-PCR. The gene encoded a 160 amino acid residue protein and had the highest similarity with human and mouse homologues, with percent identities being 93.6%, 90.5%, respectively. Semi-quantitative RT-PCR analysis of mRNA from different normal tissues indicted that the TNNC2 gene was expressed in the skeletal muscle and the levels of expression were higher in the longissimus dorsi of the Duroc pig than in the same tissue of the Lantang pig.

[Identification of differential expression ESTs in pig muscle tissue by DHPLC].

The differential expression ESTs in muscle tissue of Large Yorkshire pig and Lantang pig, one of the local pig breeds in Guangdong province, were identified with DHPLC system and graphic analysis software LabWork4.0, and both methods verified the true differential display bands. The results showed that DHPLC can quickly and accurately detect differential expression mRNA profiles of different tissues, and can be widely used to study mRNA expression, differential expression of different animal tissues under variant environments.