Comprehensive investigation on non-volatile and volatile flavor compounds in the Morchella sextelata and Morchella importuna by UPLC-MS/MS and GC × GC-TOF-MS.

Morchella sextelata and Morchella importuna are the main cultivars of morel. However, the key compounds affecting their flavors (taste and odor) are currently unknown. Here, an ultra performance tandem mass spectrometry combined with two-dimensional gas chromatography-time-of-flight mass spectrometry method was used to detect and relatively quantify the metabolites in both morel cultivars. A total of 631 non-volatile compounds and 242 volatile compounds were identified. The odor activity value was calculated to assess the contribution of key odor volatile. The results indicated that M. importuna had a sweeter flavor than M. sextelata. The former posed more prominent mushroom flavor than the latter based on the correlation analysis of the metabolites. The flavor differences of the two morel cultivars are highly relevant with the content of lipids, carbohydrates, amino acids and derivatives, alcohols and ketones. This study provides new insights into the theoretical basis for the flavor differences in both morel cultivars.

Characteristic fingerprints and comparison of volatile flavor compounds in Morchella sextelata under different drying methods.

Morchella sextelata is a precious and popular commercial edible fungus that was developed recently in China. This research aimed to characterize the volatile profiles of M. sextelata under three dehydration methods (freeze, hot air, and natural air drying). Comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-ToF-MS) was shown to the best choice to discriminate the volatile profiles of M. sextelata Characteristic flavor substances of M. sextelata were eight-carbon-containing (C8) compounds, hexanal, 2(5 h)-furanone, and benzaldehyde. Drying methods had significant influences on the volatile flavor profiles of M. sextelata, and 104 differential compounds were screened by multivariate statistical analysis. Freeze-dried samples had the most abundant volatile compounds and maintained more alcohols, ketones, aldehydes, and esters described as mushroom, sweet, and green flavor, like 1-octen-3-ol, 1-octen-3-one, nonanal, 2,3-butanedione, and so on. Hot air-drying promoted the production of heterocycles and ketones with roasted flavor due to the thermalreaction, such as 2-cyclohexen-1-one, furan, 3-phenyl-, etc. Natural air-drying resulted in acids releasing an unpleasant flavor, e.g., acetic acid, 2-methylbutanoic acid, etc. Overall, thermal reaction combined with vacuum conditions might be suitable for maintaining and enriching the aroma flavor of dried true morels.

The effect of music therapy on delirium in patients receiving mechanical ventilatory support in the Intensive Care Unit: A protocol for systematic review and meta-analysis.

BACKGROUND: Delirium is a very common sick syndrome in patients receiving mechanical ventilatory support in the Intensive Care Unit (ICU). Music therapy is a promising non-pharmacological intervention. However, its effect on the duration, incidence and severity of delirium is unknown. So we will perform a systematic review and meta-analysis to evaluate the effect of music therapy on delirium in patients receiving mechanical ventilatory support in the ICU. METHODS: This systematic review was registered in the PROSPERO. We will follow the Preferred Reporting Items for Systematic Reviews and Meta-analysis Protocol to accomplish the systematic review protocol. Searches of PubMed, EMbase, the Cochrane library, CBM, CNKI and Wanfang databases will be conducted through computer to collect randomized controlled trials (RCTs) on the effects of music therapy on delirium in patients receiving mechanical ventilatory support in the ICU. The search time will be all from database establishment to April 2023. Two evaluators will independently screen the literature, extract information and evaluate the risk of bias of included studies, then data analysis will be performed using Stata 14.0 software. RESULTS: The results of this systematic review and meta-analysis will be publicly available and published in a peer-reviewed journal. CONCLUSION: This study will provide evidence-based medical evidence for music therapy to control delirium in patients receiving mechanical ventilatory support in the ICU.

Partial enzymolysis affects the digestion of tamarind seed polysaccharides in vitro: Degradation accelerates and gut microbiota regulates.

Two hydrolyzed fractions of tamarind seed polysaccharide (TSP), denoted ETSP1 (176.68 kDa) and ETSP2 (34.34 kDa), were prepared by partial degradation via endo-xyloglucanase, and then characterized and evaluated by simulated gastrointestinal digestion in vitro. The results showed that the hydrolyzed TSPs remained indigestible in gastric and small intestinal media, and were fermented by gut microbiota, similar to the native TSP (Mw = 481.52 kDa). Although the degradation of hydrolyzed TSPs was accelerated during fermentation with a decreasing degree of polymerization, the content of produced total short-chain fatty acids (SCFAs) decreased. After fermentation, the gut microbiota composition was modified, esp. the Firmicutes/Bacteroidetes ratio decreased (1.06 vs. 0.96 vs. 0.80) with a decreasing degree of polymerization, which implied that the potential anti-obesity prebiotic effect was enhanced. At the genus level, hydrolyzed TSPs maintained similar roles as native TSP, including promoting beneficial bacteria (Bifidobacterium, Parabacteroides, and Faecalibacterium) and inhibiting enteropathogenic bacteria (Escherichia-Shigella and Dorea). Moreover, ETSP1 had additional potential due to abundant Bacteroides vulgatus (LDA = 4.68), and ETSP2 might perform better as related to Bacteroides xylanisolvens (LDA = 4.40). All these results indicated the prebiotic potential of hydrolyzed TSP with detailed information about changes in degradation and gut microbiota based on enzyme-hydrolysis.

Ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry based untargeted metabolomics to reveal the characteristics of Dictyophora rubrovolvata from different drying methods.

Dictyophora rubrovolvata is a highly valuable and economically important edible fungus whose nutrition and flavor components may vary based on drying methods. Herein, an untargeted ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) metabolomics method combined with multivariate analysis was first performed to characterize the metabolomics profiles of D. rubrovolvata upon different drying treatments, viz., coal burning drying (CD), electrothermal hot air drying (ED), and freeze drying (FD). The results indicated that 69 differential metabolites were identified, vastly involving lipids, amino acids, nucleotides, organic acids, carbohydrates, and their derivatives, of which 13 compounds were confirmed as biomarkers in response to diverse drying treatments. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis illustrated that differential metabolites were significantly assigned to 59, 55, and 60 pathways of CD vs. ED, CD vs. FD, and FD vs. ED groups, respectively, with 9 of the top 20 KEGG pathways shared. Specifically, most of lipids, such as fatty acyls, glycerophospholipids and sphingolipids, achieved the highest levels in D. rubrovolvata after the CD treatment. ED method substantially enhanced the contents of sterol lipids, nucleotides, organic acids and carbohydrates, while the levels of amino acids, prenol lipids and glycerolipids were elevated dramatically against the FD treatment. Collectively, this study shed light on metabolomic profiles and proposed biomarkers of D. rubrovolvata subjected to multiple drying techniques, which may contribute to quality control and drying efficiency in edible fungi production.

Resistance of MMTV-NeuT/ATTAC mice to anti-PD-1 immune checkpoint therapy is associated with macrophage infiltration and Wnt pathway expression.

One of the central challenges for cancer therapy is the identification of factors in the tumor microenvironment that increase tumor progression and immune tolerance. In breast cancer, fibrosis is a histopathologic criterion for invasive cancer and poor survival that results from inflammatory factors and remodeling of the extracellular matrix to produce an immune tolerant microenvironment. To determine whether tolerance is associated with the immune checkpoint, Programmed Cell Death 1 (PD-1), NeuT/ATTAC mice, a conditional model of mammary fibrosis that we recently developed, were administered a murine-specific anti-PD-1 mAb related to pembrolizumab, and drug response was monitored by tumor development, imaging mass cytometry, immunohistochemistry and tumor gene expression by RNAseq. Tumor progression in NeuT/ATTAC mice was unaffected by weekly injection of anti-PD-1 over four months. Insensitivity to anti-PD-1 was associated with several processes, including increased tumor-associated macrophages (TAM), epithelial to mesenchymal transition (EMT), fibroblast proliferation, an enhanced extracellular matrix and the Wnt signaling pathway, including increased expression of Fzd5, Wnt5a, Vimentin, Mmp3, Col2a1 and Tgfß1. These results suggest potential therapeutic avenues that may enhance PD-1 immune checkpoint sensitivity, including the use of tumor microenvironment targeted agents and Wnt pathway inhibitors.

Metabolomics Analysis of Morchella sp. From Different Geographical Origins of China Using UPLC-Q-TOF-MS.

The morel mushroom (Morchella sp.) is reputed as one of the most highly-prized edible fungi with mounting cultivated area as well as commercial popularity in China. To date, optimized methods specific for quality evaluation and constituent analysis of Morchella sp. are still non-available, impeding the healthy and sustainable development of this industry. Herein, an untargeted UPLC-Q-TOF-MS-based metabolomics approach was performed to characterize the metabolite profiles of morel samples from four distinct geographical origins of China, viz. Gansu, Guizhou, Liaoning, and Henan province. A total of 32 significantly different metabolites assigned to lipids (19), organic acids (9), amino acids (3), and ketones (1) were identified to distinguish the geographic-segregation samples amenable to multivariate analysis. These metabolites may serve as molecular markers indicative of specific regions. More importantly, the lipid, protein and amino acid metabolism were responsible for geographic differences as revealed by KEGG pathway enrichment analysis. Collectively, this study not only pioneered high-throughput methodology to evaluate quality of Morchella sp. and distinguish geographical origins in a sensitive, rapid and efficient manner, but also shed light on the potential link between physiochemical variation and geological origins from a metabolic perspective, which may be conducive to the advancement of edible fungi industry and establishment of food traceability system.

Combination of untargeted metabolomics approach and molecular networking analysis to identify unique natural components in wild Morchella sp. by UPLC-Q-TOF-MS.

Morchella sp. is a typical edible fungus. However, its unique natural products, especially bioactive composition, are rarely reported. In this study, an untargeted metabolomics approach combined with multivariate statistical analysis was employed to screen the differential metabolites in Morchella sp. compared to four other edible fungi. Among the screened 50-top differential metabolites, 18 compounds involving fatty acids and peptides showed higher content in Morchella sp.. A unique peptide of desferriferricrocin was identified. Subsequently, molecular networking analysis revealed three novel homologous compounds of desferriferricrocin, which were annotated as desferriferrichrome, desferriferrichrome C, and a new homolog not previously reported. These results were further verified by quantitative analysis. To the best of our knowledge, this is the first report of four peptides in Morchella sp..

Occurrence and Risk Assessment of Dietary Exposure to Deoxynivalenol in Wheat-Based Products Based Different Wheat-Producing Area for the Inhabitants in Shanghai, China.

Deoxynivalenol (DON) is one of the major mycotoxins that contaminate cereals. In this study, we determined the DON level in wheat-based products from Chinese five main production areas collected in Shanghai and calculated the daily intake of DON for inhabitants using the point evaluation and the probabilistic evaluation based on Monte Carlo simulation. The results showed the positive rates of DON in the products were higher than 80.0%, with the concentrations ranging from 41.8 to 1110 µg/kg. The estimated mean daily intakes of DON for 7- to 10-year-old children and adults groups were below 1 µg/kg bw/day, the provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), suggesting no health risks for the consumers. However, the 99th percentiles of dietary DON exposures for children and adults exceeded the PMTDI, indicating adverse health effects might occur if the two groups intake highly contaminated wheat-based products. The potential health risks for the two groups exposed to DON in the wheat-based products from the Middle and Lower Yangtze Valley (MLYV) were higher than those from the other areas in China.

The Possible Transmission and Potential Enterotoxicity of Bacillus cereus on Lettuce Farms in Five Chinese Provinces.

Bacillus cereus is a well-characterized human pathogen that produces toxins associated with diarrheal and emetic foodborne diseases. To investigate the possible transmission of B. cereus on lettuce farms in China and determine its enterotoxicity, (I) a total of 524 samples (lettuce: 332, soil: 69, water: 57, manure: 57, pesticide: 9) were collected from 46 lettuce farms in five Chinese provinces, (II) multilocus sequence typing (MLST) was used to classify B. cereus isolates and for trace analysis, and (III) the presence of toxin genes and enterotoxins (Hbl and Nhe) was detected in 68 strains. The results showed that one hundred and sixty-one lettuce samples (48.5%) tested positive for B. cereus at levels ranging from 10 to 5.3 × 104 CFU/g. Among the environmental sample categories surveyed, the highest positive rate was that of the pesticide samples at 55.6%, followed by soil samples at 52.2% and manure samples at 12.3%. Moreover, one hundred isolates of B. cereus yielded 68 different sequence types (STs) and were classified into five phylogenetic clades. Furthermore, Nhe toxin genes (nheA, nheB, nheC) were broadly distributed and identified in all 68 strains (100%), while Hbl toxin genes (hblA, hblC, hblD) were present in 61 strains (89.7%), entFM was detected in 62 strains (91.2%), and cytK was found in 29 strains (42.6%). All strains were negative for ces. As for the enterotoxin, Nhe was observed in all 68 isolates carrying nheB, while Hbl was present in 76.5% (52/68) of the strains harboring hblC. This study is the first report of possible B. cereus transmission and of its potential enterotoxicity on lettuce farms in China. The results showed that soil and pesticides are the main sources of B. cereus on lettuce farms in China, and the possible transmission routes are as follows: soil-lettuce, manure-lettuce, pesticide-lettuce, manure-soil-lettuce, and water-manure-soil-lettuce. Furthermore, the B. cereus isolates, whether from lettuce or the environment, pose a potential risk to health.

Determination and dietary risk assessment of 284 pesticide residues in local fruit cultivars in Shanghai, China.

The presence of pesticide residues has become one of the main risk factors affecting the safety and quality of agro-food. In this study, a multi-residue method for the analysis of 284 pesticides in five local fruit cultivars in Shanghai was developed based on ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS). The limits of determination and the limits of quantitation of pesticides were 0.6-10 and 2-30 µg/kg, respectively. A total of 44, 10, 10, 18, and 7 pesticides were detected in strawberries, watermelons, melons, peaches, and grapes, respectively. The pesticide levels in 95.0% of the samples were below the maximum residual limits (MRLs) prescribed by China, and in 66.2% of the samples below the EU MRLs. The dietary risk assessment study showed big differences in the chronic and acute exposure risk values among different Chinese consumer groups. Through fruit consumption, children/females showed higher exposure risks than adults/males. But both the risk values were less than 100%, indicating that potential dietary risk induced by the pesticides was not significant for Chinese consumers. Nevertheless, certain measures are needed for both growers and the government in order to decrease the MRL-exceeding rate of pesticide residues and ensure the quality and safety of fruits for consumers.

Biodegradation of mycotoxin fumonisin B1 by a novel bacterial consortium SAAS79.

Fumonisin B1 (FB1) contamination in cereals and cereal products remains an important aspect of food safety because of its wide distribution and the potential health hazard. However, only a few microorganisms have been reported to effectively degrade FB1. In this present study, a bacterial consortium SAAS79 with highly FB1-degrading activity was isolated from the spent mushroom compost. The combination of antibiotic-driven selection and 16S rDNA sequencing identified the Pseudomonas genus as the key FB1-degrading member. The microbial consortium could degrade more than 90% of 10 µg/mL FB1 after incubation for 24 h at pH of 5-7 and temperature of 28-35 °C. The enzymes from the intracellular space were proved to be responsible for FB1 degradation, which eliminated about 90% of 10 µg/mL FB1 in 3 h. Besides, liquid chromatography time-of-flight mass spectrometry (LC-TOF/MS) analysis identified two degradation products of FB1, and their toxicity on the monkey kidney cells (MARC-145) was significantly lower (p < 0.05) compared with the parent FB1. Overall, the consortium SAAS79 and its crude enzymes may be a potential choice for the decontamination of FB1 in the feed and food industry. Also, the bacterial consortium provides a new source of genes for the development of enzymatic detoxification agent.

A method based on amino-modified magnetic nanoparticles to extract DNA for PCR-based analysis.

DNA extraction using magnetic particles (MPs) is a simple and rapid process. MPs directly combine with DNA, thereby facilitating removal of impurities in complex samples by magnetic attraction. Amino-modified magnetic nanoparticles (AMNPs) have been described as poor substrates for DNA extraction because it was difficult to desorb DNA from the AMNPs for downstream assays. In this study, we proposed to use the complexes of AMNPs and DNA directly as templates for PCR, thereby bypassing the difficulty of desorbing DNA from AMNPs. At first, we compared three distinct chemical modifications for magnetic nanoparticles (hydroxyl modified-, carboxyl modified-, and amino modified-magnetic nanoparticles) for the extraction of DNA under experimental conditions compatible with downstream assays (e.g., PCR). Under such conditions, we demonstrated that only the AMNPs had a powerful adsorption capability for DNA with 98% separation rate. We directly employed the complexes of AMNPs and extracted DNA as templates for PCR, which reduced the separation steps and minimized the loss of DNA. Notably, we minimized AMNPs-caused inhibition of the PCR by adding BSA to the PCR mixture. The AMNPs extraction was successfully applied for the detection of a genetically modified organism, species identification, and an allergen in a heterogenous mixture. The AMNPs-based extraction method is a simple and rapid process to extract DNA and even trace amounts of DNA for PCR-based analysis.

Construction of a genetic linkage map of Lentinula edodes based on SSR, SRAP and TRAP markers.

Genetic mapping is a basic tool for eukaryotic genomic research. It allows the localization of genes or quantitative trait loci (QTLs) and map-based cloning. In this study, we constructed a linkage map based on DNA samples from a commercial strain L808, including two parental monokaryons and 93 single spore isolates considered with segregating to 1:1:1:1 at four mating types (A1B1, A1B2, A2B1 and A2B2). Using Simple Sequence Repeats (SSR), Sequence Related Amplified Polymorphism (SRAP), Target Region Amplified Polymorphism (TRAP) molecular markers, 182 molecular markers and two mating factors were located on 11 linkage groups (LGs). The total length of the map was 948.083 centimorgan (cM), with an average marker interval distance of 4.817 cM. Only two gaps spanning more than 20 cM was observed. The probability of 20 cM, 10 cM, 5 cM genetic distance cover one marker was 99.68%, 94.36%, 76.43% in our genetic linkage map, respectively. This is the first linkage map of Lentinula edodes using SSR markers, which provides essential information for quantitative trait analyses and improvement of genome assembly.

Enhancement of PCR Sensitivity and Yield Using Thiol-modified Primers.

Various additives can enhance the quality of PCR amplification, but these generally require considerable optimization to achieve peak performance. Here, we demonstrate that the use of thiol-modified primers can enhance both PCR sensitivity and yield. In experiments with V. parahaemolyticus genomic DNA, this primer modification enhances PCR sensitivity by more than 100-fold, with accompanying improvements in amplicon yield. Then, an artificial plasmid with the same primer binding regions and different internal amplification sequence was designed. The result showed that the amplification also be improved by using the same thiol-modified primers. It indicated the enhancement was not caused by the effect of the thiol-modified primers on the second structure of amplification sequence. Subsequent experiments demonstrate that the effects of this modification are potentially due to altered interaction between the primers and proteins in the reaction mixture. Amplification with thiol-modified primers was strongly inhibited by the presence of extraneous proteins relative to standard DNA primers, which indicates that thiol-modified primers may be inhibited due to interaction with these proteins. In contaminant-free reactions, however, the thiol-modified primers might interact more strongly with DNA polymerase, which could in turn improve PCR amplification.

Liquid chromatography-mass spectrometry method for evaluating the dissipation dynamics of cyromazine and its metabolite in Agaricus bisporus and dietary risk assessment.

Providing guidance on the reasonable use of pesticide in agricultural production is of particular importance for ensuring food safety. In the present study, a field trial was performed to study the dissipation and accumulative pattern of cyromazine (CA) and its metabolite in Agaricus bisporus (A. bisporus) cultivation. An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was first developed and validated for the determination of CA and melamine (MEL) in the casing soil and fruiting body. During the cultivation period, the dissipation rates of CA in the casing soil were between 51.57 and 63.48% at three dose groups. The fruiting body presented higher accumulation ability for MEL compared with CA. The terminal residues of MEL never exceeded the maximum residue limits (MRLs) in food. In addition, the intake health risk from the CA and MEL residues in the fruiting body were negligible to humans. This study will help to provide valuable guidance on the application strategies of CA in A. bisporus cultivation.

Development and Validation of a Liquid Chromatography-Tandem Mass Spectrometry Method Coupled with Dispersive Solid-Phase Extraction for Simultaneous Quantification of Eight Paralytic Shellfish Poisoning Toxins in Shellfish.

In this study, a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for simultaneous determination of eight paralytic shellfish poisoning (PSP) toxins, including saxitoxin (STX), neosaxitoxin (NEO), gonyautoxins (GTX1-4) and the N-sulfo carbamoyl toxins C1 and C2, in sea shellfish. The samples were extracted by acetonitrile/water (80:20, v/v) with 0.1% formic and purified by dispersive solid-phase extraction (dSPE) with C18 silica and acidic alumina. Qualitative and quantitative detection for the target toxins were conducted under the multiple reaction monitoring (MRM) mode by using the positive electrospray ionization (ESI) mode after chromatographic separation on a TSK-gel Amide-80 HILIC column with water and acetonitrile. Matrix-matched calibration was used to compensate for matrix effects. The established method was further validated by determining the linearity (R² ≥ 0.9900), average recovery (81.52-116.50%), sensitivity (limits of detection (LODs): 0.33-5.52 µg·kg-1; limits of quantitation (LOQs): 1.32-11.29 µg·kg-1) and precision (relative standard deviation (RSD) ≤ 19.10%). The application of this proposed approach to thirty shellfish samples proved its desirable performance and sufficient capability for simultaneous determination of multiclass PSP toxins in sea foods.

(17)O NMR and Raman Spectroscopies of Green Tea Infusion with Nanomaterial to Investigate Their Properties.

(17)O NMR and Raman spectrograms of green tea infusions with nanomaterial were investigated. Different green tea infusions were prepared by steeping tea powder with different concentrations of nanomaterial aqueous solution. The tea infusions were tested with (17)O NMR and Raman spectroscopies. The (17)O NMR results showed that line width increased to 90 in the tea infusions after nanomaterial was added as a result of the effects of the self-association of Ca(2+) and tea polyphenol. The results of Raman spectroscopy showed that, in tea infusions, the enhancement of C─C and C─O stretching vibrations suggest an increase in the number of effective components in water.

[Spatiotemporal distribution characteristics and causes of sunny days' heat island effect in Chengdu City of Southwest China].

Based on 99 clear sky Terra satellite images of Chengdu City in 2005-2010, and by using a novel automatic extraction method of suburb temperature, i. e., each city-circle temperature jump, this paper studied the spatiotemporal variation characteristics of the urban heat island (UHI) effect in the City in 2005-2010, and analyzed the causes of the variation characteristics. In the study period, the central area of the largest and strongest UHI was in the Jinhua Town located in the southwest of Chengdu. The UHI effect had no significant spatial variation, but the range and intensity of the UHI effect tented to be decreased. The intra-annual UHI intensity and area within the ring roads showed a three-peak distribution pattern, with the peak values appeared in April, July, and October, and the intensity reached the maximum in July. The UHI intensity in Chengdu was attenuated by the decrease of air temperature and the increase of precipitation and urban vegetation cover.

Purification and characterization of a novel small-molecule polysaccharide from the Maitake medicinal mushroom Grifola frondosa (higher Basidiomycetes).

A novel small-molecule polysaccharide with a molecular mass of 2.6 kDa, was isolated from the culinary-medicinal Maitake mushroom Grifola frondosa. GFPS is composed of fucose, rhamnose, galactose, glucose, and mannose; galactose, glucose, and mannose were the dominant monosaccharides. Absorption peaks at 1077 cm-1, 1024 cm-1, and 873 cm-1, as revealed by infrared spectrum, suggesting that GFPS consists of pyranoside. GFPS significantly enhanced the production of nitric oxide and secretion of cytokines (tumor necrosis factor-α, interleukin-1ß, and interleukin-δ) from macrophages in vitro. These results indicate that this novel small-molecule polysaccharide might be beneficial for immune defense.