Advanced development in chemical analysis of Cordyceps

Establishment of a genetic transformation system for cordycipitoid fungus Cordyceps chanhua

Cordyceps chanhua is a well-known edible and medicinal mushroom with a long history of use in China, and it contains a variety of secondary metabolites with interesting bioactive ingredients. However, recent researches have mainly focused on cultivation conditions, secondary metabolite compositions and pharmacological activities of C. chanhua, the lack of an efficient and stable genetic transformation system has largely limited further research on the relationship between secondary metabolites and biosynthetic gene clusters in C. chanhua. In this study, single-factor experiments were used to compare the effects of different osmotic stabilizers, enzyme concentrations and enzyme digestion times on protoplast yield, and we found that the highest yield of 5.53 × 108 protoplasts/mL was obtained with 0.7 M mannitol, 6 mg/mL snail enzyme and 4 h of enzyme digestion time, and the regeneration rate of protoplasts was up to approximately 30% using 0.7 M mannitol as an osmotic stabilizer. On this basis, a PEG-mediated genetic transformation system of C. chanhua was successfully established for the first time, which lays the foundation for further genetic transformation of C. chanhua.

Characteristics of exopolysaccharides from Paecilomyces hepiali and their simulated digestion and fermentation in vitro by human intestinal microbiota

The metabolic process of polysaccharides in gastrointestinal digestions and the effects of the resulting carbohydrates on the composition of gut microbes are important to explore their prebiotic properties. Therefore, the purpose of this study was to investigate the simulated digestion and fecal fermentation in vitro of three fractions (PHEPSs-1, PHEPSs-2 and PHEPSs-3) purified from the crude exopolysaccharides of Paecilomyces hepiali HN1 (PHEPSs) and to explore the potential prebiotic mechanisms. The three purified fractions were characterized by HPLC, UV, FT-IR, SEM and AFM, and they were all of galactoglucomannan family with molecular weight of 178, 232 and 119 kDa, respectively. They could resist the simulated gastrointestinal digestions, but they were metabolized in fecal fermentation in vitro. Furthermore, the mannose in PHEPSs showed a higher utilization rate than that of glucose or galactose. The proliferation effects of PHEPSs on Bifidobacterium and Lactobacillus were weaker significantly than those of fructooligosaccharides before 12 h of fecal fermentation, but stronger after 24 h of fecal fermentation. Meanwhile, higher levels of short-chain fatty acids were found in PHEPSs groups when the fecal fermentation extended to 36 h. Therefore, PHEPSs are expected to have a potent gut healthy activity and can be explored as functional food ingredients.

Characterisation and identification of chemical constituents in aqueous extract of Fomes officinalis Ames based on ultrahigh-performance liquid chromatography tandem quadrupole-Orbitrap high-resolution mass spectrometry

INTRODUCTION

Fungal species are an attractive resource for physiologically functional food and drug precursor. Fomes officinalis Ames, a medicinal fungus, is traditionally used as a folk medicine in traditional Chinese medicine prescription for the therapy of cough and asthma. The water-soluble substances in Chinese herbal medicines are likely to play an important physiological function. However, information on probing and identifying chemical components of the aqueous extract of Fomes officinalis Ames (AFO) remains unknown.

OBJECTIVE

This study was conducted to screen and characterise the chemical components of AFO.

MATERIAL AND METHODS

An effective and sensitive ultrahigh-performance liquid chromatography tandem quadrupole-Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap-HRMS) method with the Full MS/PIL/dd-MS2 acquisition approach was applied for the profiling of chemical components in AFO. An HSS T3 column was used for component separation, and a strategy of simultaneous targeted and untargeted multicomponent characterisation was implemented. Multiple identification approaches were used, including accurate molecular mass and elemental composition matching, literature and database searching, and fragmentation rules elucidation.

RESULTS

A total of 115 components, including 20 amino acids and derivatives, six nucleobases, nine nucleosides, 75 dipeptides, two tripeptides, and three other components, were tentatively identified. Among them, the targeted exploring method screened six nucleobases and nine nucleosides including modified nucleosides. To our best knowledge, this is the first time a report has been done on the presence of the 115 compounds in AFO.

CONCLUSION

Profiling and characterisation compounds of AFO enriched its material basis, which would lay the foundation for improving potential medicinal and nutritional values and effecting comprehensive quality control of Fomes officinalis Ames.

An authentic assessment method for cordyceps sinensis

Cordyceps Sinensis, renowned for its diverse pharmacological properties and the rarity of its natural species, faces significant challenges due to rampant adulteration by counterfeit products. Consequently, there is a crucial need to reliably identify Cordyceps species to ensure their quality and efficacy. While current analytical techniques predominantly rely on LC-MS, there remains a notable deficiency and substantial demand for the development of a unified, reproducible, and fast method suitable for commercial applications. In this study, we employed a cost-effective and straightforward approach utilizing headspace GC-MS to authenticate Cordyceps sinensis. This method enables the comprehensive analysis of the chemical profile, facilitating the identification of quality and authenticity in Cordyceps samples. Through a comparative analysis of the chemical profiles of seven authentic Cordyceps samples with seven other Cordyceps samples, we propose a Quality Assessment System for Authentic Cordyceps, encompassing the following criteria: 1) the presence of 29 compounds commonly found in authentic Cordyceps within the chemical profile, and 2) the area ratio of 3-methylbutanal to 2-methylbutanal falling within the range of 2.09-3.01. This method exhibits considerable promise as a standardized, reproducible, and expeditious technique for the quality assessment and authentication of Cordyceps.

Unique Bioactives from Zombie Fungus (Cordyceps) as Promising Multitargeted Neuroprotective Agents

Cordyceps, also known as "zombie fungus", is a non-poisonous mushroom that parasitizes insects for growth and development by manipulating the host system in a way that makes the victim behave like a "zombie". These species produce promising bioactive metabolites, like adenosine, β-glucans, cordycepin, and ergosterol. Cordyceps has been used in traditional medicine due to its immense health benefits, as it boosts stamina, appetite, immunity, longevity, libido, memory, and sleep. Neuronal loss is the typical feature of neurodegenerative diseases (NDs) (Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS)) and neurotrauma. Both these conditions share common pathophysiological features, like oxidative stress, neuroinflammation, and glutamatergic excitotoxicity. Cordyceps bioactives (adenosine, N6-(2-hydroxyethyl)-adenosine, ergosta-7, 9 (11), 22-trien-3β-ol, active peptides, and polysaccharides) exert potential antioxidant, anti-inflammatory, and anti-apoptotic activities and display beneficial effects in the management and/or treatment of neurodegenerative disorders in vitro and in vivo. Although a considerable list of compounds is available from Cordyceps, only a few have been evaluated for their neuroprotective potential and still lack information for clinical trials. In this review, the neuroprotective mechanisms and safety profile of Cordyceps extracts/bioactives have been discussed, which might be helpful in the identification of novel potential therapeutic entities in the future.

Comparative metabolic profiling of mycelia, fermentation broth, spore powder and fruiting bodies of Ophiocordyceps gracilis by LC-MS/MS

INTRODUCTION

Ophiocordyceps gracilis, a type of edible and medicinal fungus, exhibits multiple health-promoting effects. Due to the scarcity of natural O. gracilis, artificial cultures have been developed as its substitutes. However, lacking comprehension of the metabolite composition of cultures limits its utilisation.

OBJECTIVE

This research aimed to evaluate the nutritional and medicinal value of four cultures of O. gracilis by analysing their metabolite composition. In addition, metabolic pathways in mycelia and fruiting bodies were analysed to explore fruiting body formation mechanism at metabolic level.

METHOD

The mycelia, fermentation broth, spore powder and fruiting bodies of O. gracilis were cultivated in this study. Their metabolite composition was compared using an untargeted metabolomics approach based on liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

Principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) showed that the four cultures have noticeable differences in metabolite composition. A total of 612 metabolites were identified, among which 159 metabolites showed significant differences, and these differential metabolites were classified into 13 categories. The metabolites in the fruiting bodies were the most abundant compared with other cultures. However, each culture had its own advantages and significantly accumulates some active metabolites respectively. Pearson's correlation analysed the mutual relationship among metabolites. In addition, seven metabolic pathways were closely related to fruiting body formation, such as "Biosynthesis of plant secondary metabolites", "amino acids metabolism", "tricarboxylic acid (TCA) cycle".

CONCLUSION

This study offered a reference to mycelia, fermentation broth, spore powder and fruiting bodies of O. gracilis as health-promoting functional foods and medicine.

A Neutral Polysaccharide from Spores of Ophiocordyceps gracilis Regulates Oxidative Stress via NRF2/FNIP1 Pathway

Ophiocordyceps gracilis (O. gracilis) is a parasitic fungus used in traditional Chinese medicine and functional foods. In this study, a neutral heteropolysaccharide (GSP-1a) was isolated from spores of O. gracilis, and its structure and antioxidant capacities were investigated. GSP-1a was found to have a molecular weight of 72.8 kDa and primarily consisted of mannose (42.28%), galactose (35.7%), and glucose (22.02%). The backbone of GSP-1a was composed of various sugar residues, including →6)-α-D-Manp-(1→, →2,6)-α-D-Manp-(1→, →2,4,6)-α-D-Manp-(1→, →6)-α-D-Glcp-(1→, and →3,6)-α-D-Glcp-(1→, with some branches consisting of →6)-α-D-Manp-(1→ and α-D-Gal-(1→. In vitro, antioxidant activity assays demonstrated that GSP-1a exhibited scavenging effects on hydroxyl radical (•OH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS•+), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•). Moreover, GSP-1a was found to alleviate H2O2-induced oxidative stress in HepG2 cells by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activities of superoxide dismutase (SOD). Furthermore, GSP-1a upregulated the mRNA expression of antioxidant enzymes such as Ho-1, Gclm, and Nqo1, and regulated the NRF2/KEAP1 and FNIP1/FEM1B pathways. The findings elucidated the structural types of GSP-1a and provided a reliable theoretical basis for its usage as a natural antioxidant in functional foods or medicine.

Cordythiazole A, the first member of thiazole alkaloids from Chinese cordyceps, with α-glucosidase inhibitory activity

Chinese cordyceps, also known as Dong-Chong-Xia-Cao, is widely recognized as a famous precious tonic herb, and used as traditional Chinese medicine for centuries. It is mainly used for regulating the immune system and improving functions of the lung and kidney, with anti-tumor, anti-inflammatory, and anti-diabetic activities. Due to its rarity and preciousness, a few chemical components are isolated and identified. Moreover, most of them are common chemical components and widely distributed in other natural resources, such as nucleosides, sterols, fatty acids, sugar alcohols, and peptides. Therefore, a large number of active substances of Chinese cordyceps is still unclear. During our search for chemical constituents of Chinese cordyceps, a new thiazole alkaloid, cordythiazole A (1), was isolated and identified. Its structure was elucidated by comprehensive spectroscopic analysis and single-crystal X-ray diffraction analysis. This is the first report of the presence of thiazole alkaloid in Chinese cordyceps, which adds a new class of metabolite of Chinese cordyceps. Furthermore, a putative biosynthesis pathway of cordythiazole A was proposed based on possible biogenic precursor, genes, and literatures. In addition, it showed α-glucosidase inhibitory activity with potency close to that of acarbose. The discovery of cordythiazole A with α-glucosidase inhibitory activity adds a new class of potential anti-diabetes ingredient in Chinese cordyceps.

Unraveling the Secrets of a Double-Life Fungus by Genomics: Ophiocordyceps australis CCMB661 Displays Molecular Machinery for Both Parasitic and Endophytic Lifestyles

Ophiocordyceps australis (Ascomycota, Hypocreales, Ophiocordycipitaceae) is a classic entomopathogenic fungus that parasitizes ants (Hymenoptera, Ponerinae, Ponerini). Nonetheless, according to our results, this fungal species also exhibits a complete set of genes coding for plant cell wall degrading Carbohydrate-Active enZymes (CAZymes), enabling a full endophytic stage and, consequently, its dual ability to both parasitize insects and live inside plant tissue. The main objective of our study was the sequencing and full characterization of the genome of the fungal strain of O. australis (CCMB661) and its predicted secretome. The assembled genome had a total length of 30.31 Mb, N50 of 92.624 bp, GC content of 46.36%, and 8,043 protein-coding genes, 175 of which encoded CAZymes. In addition, the primary genes encoding proteins and critical enzymes during the infection process and those responsible for the host-pathogen interaction have been identified, including proteases (Pr1, Pr4), aminopeptidases, chitinases (Cht2), adhesins, lectins, lipases, and behavioral manipulators, such as enterotoxins, Protein Tyrosine Phosphatases (PTPs), and Glycoside Hydrolases (GHs). Our findings indicate that the presence of genes coding for Mad2 and GHs in O. australis may facilitate the infection process in plants, suggesting interkingdom colonization. Furthermore, our study elucidated the pathogenicity mechanisms for this Ophiocordyceps species, which still is scarcely studied.

Comparative metabolic profiling of wild Cordyceps species and their substituents by liquid chromatography-tandem mass spectrometry

Cordyceps is a genus of ascomycete fungi and used widely in fungal drugs. However, in-depth studies of the metabolites of wild Cordyceps species and their substituents are lacking. In this study, a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolomics analysis was carried out to comprehensively profile the metabolites in wild Chinese Cordyceps species (Ophiocordyceps sinensis (Berk.) G.H. Sung, J.M. Sung, Hywel-Jones and Spatafora 2007) from Naqu (NCs) and Yushu (YCs) and their substituents including artificially cultivated Cordyceps species (CCs) and mycelia. A total of 901 metabolites were identified in these samples, including lipids, amino acids, nucleosides, carbohydrates, organic acids, coenzymes, vitamins, alkaloids and their derivatives. Univariate and multivariate statistical analyses revealed remarkable differences and significantly different metabolites among them. Seventy amino acid-relevant metabolites were analyzed quantitatively in four samples for the first time. The four samples contained abundant L-glutamic acid and oxidized glutathione as well as multiple unique amino acid-relevant metabolites (e.g., 3-chloro-L-tyrosine, 6-aminocaproic acid, L-theanine, anserine, γ-glutamyl-cysteine). Collectively, our study provides rich metabolic information of wild Cordyceps species and their substituents, which could facilitate their quality control and optimal utilization.

A simple, rapid, sensitive and eco-friendly LC-MS/MS method for simultaneous determination of free cordycepin and isocordycepin in 10 different kinds of Cordyceps

A simple, rapid, sensitive and eco-friendly liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of free cordycepin (3′-deoxyadenosine) and isocordycepin (2′-deoxyadenosine) in 10 kinds of Cordyceps samples. The samples were prepared by ultrasonic extraction at 75 °C for 30 min with boiling water as the extraction solvent. The LC separation was performed on an Agilent poroshell 120 SB-Aq C18 column (3.0 × 50 mm, 2.7 μm) in isocratic mode with an eco-friendly mobile phase (2% ethanol containing 0.2% acetic acid) at a flow rate of 0.6 mL min−1, and detected by MS/MS in positive mode with multiple reaction monitoring (MRM). The developed method showed good linearity (r > 0.9990), sensitivity (LODs = 0.04 pg, LOQ = 0.1 pg), precision (RSD ≤ 3.8%) and stability (RSD ≤ 3.6%). The recoveries of developed method were 94.4–109.5% (RSD ≤ 5.5%). Compared with reported methods, the current method was rapid (less than 35% analytical time), sensitive (more than 5 folds), and eco-friendly (less than 10 μL harmful organic solvent). 10 different kinds of Cordyceps samples (40 batches) were tested by the developed method. Codycepin was only found in Cordyceps millitaris and C. millitaris fruiting body, and isocordycepin was detected in Cordyceps sinensis and other 6 Cordyceps samples. The developed method would be an improved method for the quality evaluation of Cordyceps samples.

Network Pharmacology and Molecular Docking Analysis Explores the Mechanisms of Cordyceps sinensis in the Treatment of Oral Lichen Planus

Objective

Oral lichen planus (OLP) is the most common potentially malignant disorder of the oral cavity. This study aimed to investigate the mechanism of action of Cordyceps sinensis in the treatment of OLP and provides a theoretical support for improving current treatment regimens for OLP.

Methods

The active components and therapeutic targets of Cordyceps sinensis were predicted and screened using the TCMSP, SymMap, PubMed, HIT 2.0, and PharmMapper databases, while the relevant OLP targets were predicted and screened using the DisGeNET and GeneCards databases. Protein-protein interactions (PPI) were examined using the String database, and Cytoscape was used to combine and illustrate the findings. GO and KEGG pathway enrichment analyses were carried out using RStudio, and AutoDock Vina and Pymol were used for molecular docking and visualization, respectively.

Results

A total of 404 potential target genes were discovered after evaluating 21 active compounds from Cordyceps sinensis. Potential therapeutic targets included 67 targets that matched and overlapped with OLP, including TNF, IL-6, CD4, EGFR, and IL1B. Key targets were predominantly engaged in the PI3K-Akt signaling pathway and the MAPK signaling pathway, according to the GO and KEGG analyses. These targets have a connection to biological processes including apoptosis signaling pathway regulation, T cell activation, and oxidative stress response. The molecular docking results showed that TNF, IL-6, CD4, EGFR, and IL1B could bind to their corresponding active components.

Conclusions

Cordyceps sinensis contains multiple components and acts on multiple targets and multiple pathways. Particularly, Cordyceps sinensis targets TNF, IL-6, CD4, EGFR, and IL1B, regulates PI3K-Akt and MAPK signaling pathways, as well as takes part in biological processes including apoptosis, T cell activation, and oxidative stress. Cordyceps sinensis could be a crucial choice in the therapy of OLP.

Comparison of Widely Targeted Metabolomics and Untargeted Metabolomics of Wild Ophiocordyceps Sinensis

The authors of this paper conducted a comparative metabolomic analysis of Ophiocordyceps sinensis (OS), providing the metabolic profiles of the stroma (OSBSz) and sclerotia (OSBSh) of OS by widely targeted metabolomics and untargeted metabolomics. The results showed that 778 and 1449 metabolites were identified by the widely targeted metabolomics and untargeted metabolomics approaches, respectively. The metabolites in OSBSz and OSBSh are significantly differentiated; 71 and 96 differentially expressed metabolites were identified by the widely targeted metabolomics and untargeted metabolomics approaches, respectively. This suggests that these 71 metabolites (riboflavine, tripdiolide, bromocriptine, lumichrome, tetrahymanol, citrostadienol, etc.) and 96 metabolites (sancycline, vignatic acid B, pirbuterol, rubrophen, epalrestat, etc.) are potential biomarkers. 4-Hydroxybenzaldehyde, arginine, and lumichrome were common differentially expressed metabolites. Using the widely targeted metabolomics approach, the key pathways identified that are involved in creating the differentiation between OSBSz and OSBSh may be nicotinate and nicotinamide metabolism, thiamine metabolism, riboflavin metabolism, glycine, serine, and threonine metabolism, and arginine biosynthesis. The differentially expressed metabolites identified using the untargeted metabolomics approach were mainly involved in arginine biosynthesis, terpenoid backbone biosynthesis, porphyrin and chlorophyll metabolism, and cysteine and methionine metabolism. The purpose of this research was to provide support for the assessment of the differences between the stroma and sclerotia, to furnish a material basis for the evaluation of the physical effects of OS, and to provide a reference for the selection of detection methods for the metabolomics of OS.

Structural Elucidation and Activities of Cordyceps militaris-Derived Polysaccharides: A Review

Cordyceps militaris is a parasitic edible fungus and has been used as tonics for centuries. Polysaccharides are a major water-soluble component of C. militaris. Recently, C. militaris-derived polysaccharides have been given much attention due to their various actions including antioxidant, anti-inflammatory, anti-tumor, anti-hyperlipidemic, anti-diabetic, anti-atherosclerotic, and immunomodulatory effects. These bioactivities are determined by the various structural characteristics of polysaccharides including monosaccharide composition, molecular weight, and glycosidic linkage. The widespread use of advanced analytical analysis tools has greatly improved the elucidation of the structural characteristics of C. militaris-derived polysaccharides. However, the methods for polysaccharide structural characterization and the latest findings related to C. militaris-derived polysaccharides, especially the potential structure-activity relationship, have not been well-summarized in recent reviews of the literature. This review will discuss the methods used in the elucidation of the structure of polysaccharides and structural characteristics as well as the signaling pathways modulated by C. militaris-derived polysaccharides. This article provides information useful for the development of C. militaris-derived polysaccharides as well as for investigating other medicinal polysaccharides.

In situ Chemical Profiling and Imaging of Cultured and Natural Cordyceps sinensis by TOF-SIMS

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a sensitive surface analytical technology, which can simultaneously acquire diverse chemical components and their precise locations on the surfaces of samples without any requirements for chemical damage pretreatments or additional matrices. Commonly, the quality control of TCMs (traditional Chinese medicines) is limited by the qualitative and quantitative evaluations of the specifically extractive constituents. In this study, a practical sample preparation strategy named two-layered media embedding sample preparation was developed to obtain ideal freezing sections of dried materials of Cordyceps sinensis. Meanwhile, the well-established sample preparation method was applied for in situ chemical profiling and imaging of natural (NCS) and cultured Cordyceps sinensis (CCS) by using TOF-SIMS. More than 200 components were tentatively identified and imaged in NCS and CCS at the same time. Mass spectrometry imaging revealed that most components have even distributions in caterpillars of Cordyceps sinensis, while TAGs, DAGs, MAGs, and FAs only have distributions outside caterpillars’ digestive chambers. This is the first time that components were in situ imaged for Cordyceps sinensis to exhibit the chemical distributions which have never been achieved by other analytical techniques so far. In addition, chemometrics was used to simplify and explain the massive TOF-SIMS mass data sets, which revealed the high chemical similarity between CCS and NCS. Furthermore, the relative quantification of TOF-SIMS data showed that CCS has comparable proportions of amino acids, nucleosides, monosaccharides, sphingolipids, sterols and other principles to NCS except for fatty acids, glycerides and glycerophospholipids. The higher amounts of TAGs and DAGs in CCS were confirmed by quantitative ¹H-NMR, indicating reliable relative quantification of TOF-SIMS. In general, our research developed a novel approach of TOF-SIMS for in situ chemical analysis of TCMs, and its successful application in comparative study of CCS and NCS suggested that TOF-SIMS is an advanced and promising analytical technology for the research of TCMs.

Development of an eco-friendly and fast HPLC method for quantitative analysis of four nucleosides in Cordyceps and related products

An eco-friendly and fast HPLC method was developed for the determination of adenosine, inosine, guanosine and uridine in Cordyceps and related products (fermented mycelia of Hirsutella sinensis andPaecilomyces hepiali). The sample was ultrasonically extracted using 0.5% phosphoric acid solutions for 2.5 min. Sample separation was performed on a Poroshell SB-Aq column (50 mm × 4.6 mm, 2.7 μm) using eco-friendly mobile phase consisting of formic acid and ammonium formate aqueous solution at a flow rate of 1.0 mL·min^-1. The detection wavelength was 260 nm. The developed HPLC method showed good linearity with correlation coefficients of 1.0000 in the test range. Good precision, repeatability and stability of this method were also observed (RSD ≤ 2.81%). The recovery ranged from 91.84%-105.19% (RSD ≤ 2.59%). Compared with reported methods, the current method did not use harmful organic solvent and took only 10.5 min. It obtained a high eco-score of 91 by the "Analytical Eco-Scale" tool. The developed method is eco-friendly and fast, which is suitable for the quality evaluation of Cordyceps and related products.

Stage- and Rearing-Dependent Metabolomics Profiling of Ophiocordyceps sinensis and Its Pipeline Products

Cordyceps, a parasitic complex of the fungus Ophiocordyceps sinensis (Berk.) (Hypocreales: Ophiocordycipitaceae) and the ghost moth Thitarodes (Lepidoptera: Hepialidae), is a historical ethnopharmacological commodity in China. Recently, artificial cultivation of Chinese cordyceps has been established to supplement the dwindling natural resources. However, much is unknown between the natural and cultivated products in terms of nutritional aspect, which may provide essential information for quality evaluation. The current study aims to determine the metabolic profiles of 17 treatments from 3 sample groups including O. sinensis fungus, Thitarodes insect and cordyceps complex, using Gas Chromatography - Quadrupole Time-of-Flight Mass Spectrometry. A total of 98 metabolites were detected, with 90 of them varying in concentrations among groups. The tested groups could be separated, except that fungal fruiting body was clustered into the same group as Chinese cordyceps. The main distinguishing factors for the groups studied were the 24 metabolites involved in numerous different metabolic pathways. In conclusion, metabolomics of O. sinensis and its related products were determined mainly by the fruiting bodies other than culture methods. Our results suggest that artificially cultured fruiting bodies and cordyceps may share indistinguishable metabolic functions as the natural ones.

mRNA-seq and miRNA-seq profiling analyses reveal molecular mechanisms regulating induction of fruiting body in Ophiocordyceps sinensis

Ophiocordyceps sinensis has been a source of valuable materials in traditional Asian medicine for over two thousand years. With recent global warming and overharvest, however, the availability of these wild fungi has decreased dramatically. While fruiting body of O. sinensis has been artificially cultivated, the molecular mechanisms that govern the induction of fruiting body at the transcriptional and post-transcriptional levels are unclear. In this study, we carried out both mRNA and small RNA sequencing to identify crucial genes and miRNA-like RNAs (milRNAs) involved in the development of fruiting body. A total of 2875 differentially expressed genes (DEGs), and 71 differentially expressed milRNAs (DEMs) were identified among the mycoparasite complex, the sclerotium (ST) and the fruiting body stage. Functional enrichment and Gene Set Enrichment Analysis indicated that the ST had increased oxidative stress and energy metabolism and that mitogen-activated protein kinase signaling might induce the formation of fruiting body. Integrated analysis of DEGs and DEMs revealed that n_os_milR16, n_os_milR21, n_os_milR34, and n_os_milR90 could be candidate milRNAs that regulate the induction of fruiting body. This study provides transcriptome-wide insight into the molecular basis of fruiting body formation in O. Sinensis and identifies potential candidate genes for improving induction rate.

Novel Fatty Acid in Cordyceps Suppresses Influenza A (H1N1) Virus-Induced Proinflammatory Response Through Regulating Innate Signaling Pathways

Influenza virus (IV) infections usually cause acute lung injury characterized by exaggerated proinflammatory responses. The paucity of therapeutic strategies that target host immune response to attenuate lung injury poses a substantial challenge in management of IV infections. In this study, we chemically synthesized a novel fatty acid (2Z,4E)-deca-2,4-dienoic acid (DDEA) identified from Chinese Cordyceps by using UHPLC-Q-TOF-MS techniques. The DDEA did not inhibit H1N1 virus replication but attenuated proinflammatory responses by reducing mRNA and protein levels of TNF-α, IFN-α, IFN-β, IL-6, CXCL-8/IL-8, CCL-2/MCP-1, CXCL-10/IP-10, CCL-3/MIP-1α, and CCL-4/MIP-1β in A549 cells and U937-derived macrophages. The anti-inflammatory effect occurred through downregulations of TLR-3-, RIG-I-, and type I IFN-activated innate immune signaling pathways. Altogether, our results indicate that DDEA may potentially be used as an anti-inflammatory therapy for the treatment of IV infections.

Determination of Adenosine and Cordycepin Concentrations in Cordyceps militaris Fruiting Bodies Using Near-Infrared Spectroscopy

Near-infrared (NIRS) spectroscopy, coupled with partial least squares regression, was used to predict adenosine and cordycepin concentrations in fruiting bodies of Cordyceps militaris. The fruiting body samples were prepared in four different sample formats, which were intact fruiting bodies, chopped fruiting bodies, dried powder, and dried crude extract. The actual amount of the adenosine and cordycepin concentrations in fresh fruiting bodies was analyzed by high-performance liquid chromatography. Results showed that the prediction models developed from the chopped samples provided excellent accuracy in both parameters with minimal sample preparation. These optimum models provided a coefficient of determination of prediction, standard error of prediction, bias, and residual predictive deviation, which were respectively 0.95, 16.60 mg kg^-1, -8.57 mg kg^-1, and 5.04 for adenosine prediction, and 0.98, 181.56 mg kg^-1, -1.05 mg kg^-1, and 8.9 for cordycepin prediction. The accuracy and performance of the model were determined by ISO12099:2017(E). It was found that these two equations can be considered to be acceptable at a probability level of 95% confidence. The NIRS technique, therefore, has the potential to be an objective method for determining the adenosine and cordycepin concentrations in C. militaris fruiting bodies.

One-Pot Derivatization for Wide-Scope Detection of Nucleobases and Deoxyribosides in Natural Medicinal Foods with Liquid Chromatography-Tandem Mass Spectrometry

A new chemical labeling-based LC-MS/MS approach was developed for quantitative profiling of nine canonical bases and deoxynucleosides (dNs) in natural products. Using 2-bromo-1-(4-dimethylamino-phenyl)-ethaone (BrDPE) as the tagging reagent, a previously unexploited N-alkylpyrimidine derivative (Nad) was created for one-pot labeling of widescope nucleobases via a flexible bromophilic substitution under mild conditions. The derivatization notably improved the LC-MS detection sensitivity by 31-107 fold, enabling a fast dilute-and-shoot analysis of highly diluted samples. The optimized and validated method demonstrated satisfactory accuracy (87-107%), precision (RSDs < 7.5%), and recovery (89-105%) for matrix-matched standard addition. The method was applied to simultaneously determine all target analytes and four uncanonical analogues and base-modified species in seven traditional health foods, which differ in contents by up to 600-fold for discrimination among samples. Further, the base-labeled Nads exhibit a unique fragmentation signature that could be used for untargeted screening of nucleobase-containing metabolites by simplified LC-MS/MS workflow to improve quality evaluation of natural medicinal products.

Quality control method of sterols in fermented Cordyceps sinensis based on combined fingerprint and quantitative analysis of multicomponents by single marker

In this study, we established a new pattern for differentiating and comprehensively evaluating the quality of fermented Cordyceps sinensis based on high-performance liquid chromatography (HPLC) fingerprint analysis combined with similar analysis (SA), principal component analysis (PCA), hierarchical cluster analysis (HCA), and the quantitative analysis of multicomponents by single marker (QAMS). These methods indicated that fermented Cordyceps sinensis samples could be categorized into one class by PCA and HCA. The fingerprints of fermented Cordyceps sinensis were established, and four HPLC peaks were identified as ergosterol, daucosterol, stigmasterol, and β-sitosterol in Jinshuibao capsules and tablets (two products of fermented Cordyceps sinensis). Ergosterol was chosen as the internal reference substance, and the relative correction factors (RCFs) between ergosterol and the other three sterols were calculated using the QAMS method. Moreover, the accuracy of the QAMS method was confirmed by comparing the relative error between the results of the method used with those of an external standard method (ESM). No significant difference between the two methods was observed. The total sterols content in Jinshuibao products were calculated by the QAMS method, and the total sterols content of the two products were similar. This study showed that the method established herein was efficient and successful in the identification fermented Cordyceps sinensis and may further act to facilitate systematic quality control of fermented Cordyceps sinensis products.

Can Cordyceps cicadae be used as an alternative to Cordyceps militaris and Cordyceps sinensis? - A review

ETHNOPHARMACOLOGICAL RELEVANCE

Cordyceps cicadae (Mig.) Massee is one of the oldest and well-known traditional Chinese medicine (TCM), with its uses recorded as far back as the 5th century A.D. For centuries, C. cicadae has been used as food, tonic and folk medicine to treat malaria, palpitations, cancer, fever, diabetes, eye diseases, dizziness, and chronic kidney diseases. Although C. cicadae has been used as TCM for over 1600 years, it is not the most popular amongst the Cordyceps family. Cordyceps Sinensis (C. sinensis) and Cordyceps militaris (C. militaris) are the most studied and widely used, with a number of commercially available products derived from these two Cordyceps species.

AIM OF THE REVIEW

This review seeks to look at the research that has been conducted on C. cicadae over the past 30 years, reporting on the biological activities, development and utilization. This information was compared to that focused on C. sinensis and C. militaris.

MATERIALS AND METHODS

A literature search was conducted on different scientific search engines including, but not limited to "Web of Science", "ScienceDirect" and "Google Scholar" to identify published data on C. cicadae, I. cicadae, P. cicadae, C. sinensis and C. militaris.

RESULTS

Research conducted on C. cicadae over the past two decades have shown that it poses similar biological properties and chemical composition as C. sinensis and C. militaris. C. cicadae has been reported to grow in many geographic locations, as compared to C. sinensis, and can be artificially cultivated via different methods.

CONCLUSION

There exists sufficient evidence that C. cicadae has medicinal benefits and contain bioactive compounds similar to those found on C. sinensis and C. militaris. However, more research and standardization methods are still needed to directly compare C. cicadae with C. sinensis and C. militaris, in order to ascertain the suitability of C. cicadae as an alternative source of Cordyceps products.

Bioactive Metabolites and Potential Mycotoxins Produced by Cordyceps Fungi: A Review of Safety

Ascomycete Cordyceps fungi such as C. militaris, C. cicadae, and C. guangdongensis have been mass produced on artificial media either as food supplements or health additives while the byproducts of culture substrates are largely used as animal feed. The safety concerns associated with the daily consumption of Cordyceps fungi or related products are still being debated. On the one hand, the known compounds from these fungi such as adenosine analogs cordycepin and pentostatin have demonstrated different beneficial or pharmaceutical activities but also dose-dependent cytotoxicities, neurological toxicities and or toxicological effects in humans and animals. On the other hand, the possibility of mycotoxin production by Cordyceps fungi has not been completely ruled out. In contrast to a few metabolites identified, an array of biosynthetic gene clusters (BGCs) are encoded in each genome of these fungi with the potential to produce a plethora of as yet unknown secondary metabolites. Conservation analysis of BGCs suggests that mycotoxin analogs of PR-toxin and trichothecenes might be produced by Cordyceps fungi. Future elucidation of the compounds produced by these functionally unknown BGCs, and in-depth assessments of metabolite bioactivity and chemical safety, will not only facilitate the safe use of Cordyceps fungi as human food or alternative medicine, but will also benefit the use of mass production byproducts as animal feed. To corroborate the long record of use as a traditional medicine, future efforts will also benefit the exploration of Cordyceps fungi for pharmaceutical purposes.

Effect of bioactive compounds extracted from Cordyceps nidus ANDES-F1080 on laccase activity of Pleurotus ostreatus ANDES-F515

Laccases are ligninolytic enzymes produced by different microorganisms, especially by fungi such as the white-rot fungus Pleurotus ostreatus. Chemical inductors have been used to promote laccase secretion due to the application of these enzymes in lignocellulosic biomass pretreatment. Cordyceps nidus ANDES-F1080 was previously described as a source of bioactive compounds that could influence the enzymatic production system of other fungi. For that reason, this study evaluates the effect of C. nidus' ANDES-F1080 extracts on the laccase activity of P. ostreatus ANDES-F515. To achieve this objective, C. nidus ANDES-F1080 was grown in four different substrates: two artificial-based and two natural-based culture media. Metabolites were extracted from C. nidus ANDES-F1080 using water and methanol as solvents. Biochemical characterization of these extracts was performed to complement the analysis of their effect on laccase activity. Our results revealed an enhancement on the laccase activity of P. ostreatus ANDES-F515 grown in natural-based cultures when C. nidus' ANDES-F1080 extracts were supplemented. The best laccase activities registered values around 10,575 ± 813 U·L^-1.

Fluorescence Detection of Deoxyadenosine in Cordyceps spp. by Indicator Displacement Assay

A rapid, sensitive and reliable indicator displacement assay (IDA) for specific detection of 2′- and 3′-deoxyadenosine (2′-dAde and 3′-dAde), the latter is also known as cordycepin, was established. The formation of inclusion complex between protonated acridine orange (AOH⁺) and cucurbit[7]uril (CB7) resulted in the hypochromic shift of fluorescent emission from 530 nm to 512 nm. Addition of cordycepin to the highly fluorescent AOH⁺/CB7 complex resulted in a unique tripartite AOH⁺/CB7/dAde complex with diminished fluorescence, and such reduction in emission intensity serves as the basis for our novel sensing system. The detection limits were 11 and 82 μM for 2′- and 3′-deoxyadenosine, respectively. The proposed method also demonstrated high selectivity toward 2′- and 3′-deoxyadenosine, owing to the inability of other deoxynucleosides, nucleosides and nucleotides commonly found in Cordyceps spp. to displace the AOH⁺ from the AOH⁺/CB7 complex, which was confirmed by isothermal titration calorimetry (ITC), UV-Visible and proton nuclear magnetic resonance (¹H-NMR) spectroscopy. Our method was successfully implemented in the analysis of cordycepin in commercially available Ophiocordyceps and Cordyceps supplements, providing a novel and effective tool for quality assessment of these precious fungi with several health benefits.

Comparative metabolic profiling of Ophiocordyceps sinensis and its cultured mycelia using GC-MS

Ophiocordyceps sinensis, one of the well-known traditional Chinese medicine, has multiple health-promoting effects. It is used as herbal remedy and health food in Asian countries, together with its cultured mycelia used as a substitute of natural O. sinensis. In the present study, natural O. sinensis collected from three geographical regions and its cultured mycelia derived from three strains were analyzed by gas chromatography-mass spectrometry (GC-MS) combined with chemometrics. A total of 72 metabolites were identified from all samples with different metabolic profiles observed between natural O. sinensis and cultured mycelia. Among them, 50 metabolites showed significant differences between natural O. sinensis and cultured mycelia. Higher levels of trehalose, glycerol and citric acid in natural O. sinensis were found compared to those in cultured mycelia, while myo-inositol and some amino acids were more abundant in cultured mycelia. In addition, chemical compositions of natural O. sinensis varied depending on the geographical regions. Natural O. sinensis from three locations were clearly differentiated by the concentrations of meso-erythritol, D-mannitol, glucose and organic acids. The current study provides a comprehensive metabolic profiles of natural O. sinensis and its cultured mycelia, which is potentially important for understanding the metabolism of O. sinensis and facilitating the application of cultured mycelia as a supplement of natural O. sinensis.

UPLC-ESI-Q-TOF-MS/MS analysis of anticancer fractions from Ophiocordyceps xuefengensis and Ophiocordyceps sinensis

Ophiocordyceps xuefengensis (O. xuefengensis), a new species of caterpillar fungus, has been identified as the sister taxon of Ophiocordyceps sinensis (O. sinensis). The aims of the present study are to evaluate the anticancer activity and to qualitatively analyze the potential bioactive chemical constituents of O. xuefengensis and O. sinensis, comparatively. An MTT assay was used to evaluate the in vitro anticancer activities of different fractions from O. xuefengensis and O. sinensis. The results show that ethyl acetate fractions of O. xuefengensis and O. sinensis have significant in vitro anticancer activity. These two bioactive fractions were analyzed by ultra-performance liquid chromatography-electrospray ionization with quadrupole-time of flight tandem mass spectrometry technology. A total of 82 compounds and 101 compounds were identified or tentatively characterized in the bioactive fractions of O. xuefengensis and O. sinensis, respectively. Among these compounds, 68 existed in both O. xuefengensis and O. sinensis. A total of 67 compounds were reported in O. xuefengensis and 8 compounds were reported in caterpillar fungus for the first time. This is the first detailed comparative analysis of the in vitro anticancer activity and chemical ingredients between O. xuefengensis and O. sinensis. The application of this work will provide reliable fundamental pharmacological substances for the use of O. xuefengensis by Yao people.

Analysis of Volatile Components in Different Ophiocordyceps sinensis and Insect Host Products

The artificial production of Ophiocordyceps sinensis mycelia and fruiting bodies and the Chinese cordyceps has been established. However, the volatile components from these O. sinensis products are not fully identified. An efficient, convenient, and widely used approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography and quadrupole time-of-flight mass spectrometry (GC×GC-QTOFMS) was developed for the extraction and the analysis of volatile compounds from three categories of 16 products, including O. sinensis fungus, Thitarodes hosts of O. sinensis, and the Chinese cordyceps. A total of 120 volatile components including 36 alkanes, 25 terpenes, 17 aromatic hydrocarbons, 10 ketones, 5 olefines, 5 alcohols, 3 phenols, and 19 other compounds were identified. The contents of these components varied greatly among the products but alkanes, especially 2,5,6-trimethyldecane, 2,3-dimethylundecane and 2,2,4,4-tetramethyloctane, are the dominant compounds in general. Three categories of volatile compounds were confirmed by partial least squares-discriminant analysis (PLS-DA). This study provided an ideal method for characterizing and distinguishing different O. sinensis and insect hosts-based products.

Fast quantification of free amino acids in food by microfluidic voltage-assisted liquid desorption electrospray ionization-tandem mass spectrometry

A method based on microfluidic voltage-assisted liquid desorption electrospray ionization-tandem mass spectrometry (VAL-DESI-MS/MS) has been developed for fast quantification of free amino acids in food. Food extracts were transferred to the microfluidic platform and analyzed by liquid desorption ESI-MS/MS. Deuterated aspartic acid (i.e., 2,2,3-d3-Asp) was used as internal standard for analysis. The method had linear calibration curves with r2 values > 0.998. Limits of detection were at the level of sub μM for the amino acids tested, i.e., glutamic acid (Glu), arginine (Arg), tyrosine (Tyr), tryptophan (Trp), and phenylalanine (Phe). To validate the proposed method in food analysis, extracts of Cordyceps fungi were analyzed. Amino acid contents were found in the range from 0.63 mg/g (Tyr in Cordyceps sinensis) to 4.44 mg/g (Glu in Cordyceps militaris). Assay repeatability (RSD) was ≤ 5.2% for all the five amino acids measured in all the samples analyzed. Recovery was found in the range from 95.8 to 105.1% at two spiking concentrations of 0.250 mg/g and 1.00 mg/g. These results prove that the proposed microfluidic VAL-DESI-MS/MS method offers a quick and convenient means of quantifying free amino acids with accuracy and repeatability. Therefore, it may have potential in food analysis for nutritional and quality assessment purposes. Graphical abstract.

Structural Characterization and Chain Conformation of Water-Soluble β-Glucan from Wild Cordyceps sinensis

Water-soluble β-d-glucan was obtained from wild Cordyceps sinensis by alkali solution and ethanol precipitation. The structure characteristics were determined using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD), methylation combined with gas chromatography-mass spectrometry, and one-/two-dimensional nuclear magnetic resonance spectroscopy. Results showed that β-d-glucan had a structure of every seven (1→3)-β-d-Glcp backbone residues with two (1→6)-β-d-Glcp branches. Additionally, conformation properties in different solvents were investigated by static light scattering, dynamic light scattering, and HPSEC with multiple detectors. It was found that β-d-glucan in 0.5 M NaOH had a narrow unimodal distribution of hydrodynamic radius displaying a spherical coil conformation, whereas it formed severe aggregation in dimethyl sulfoxide. In 0.1 M NaNO₃, β-d-glucan mainly existed as a rod-like conformation corresponding to a helical structure together with small aggregates (10%). This work added more information to the understanding of C. sinensis polysaccharides.

Simultaneous Quantification of Adenosine and Deoxyadenosine Isomers in Foods with High Sensitivity

Simultaneous quantification of adenosine and deoxyadenosine isomers, including 2'-deoxyadenosine (dA) and 3'-deoxyadenosine (cordycepin, COR) is a challenge because they are very similar in chemical structure. In some previous studies on food ingredients, adenine and dA might be mistakenly detected as COR that has been shown to have multiple health benefits. In this work, we developed a novel HPLC method with fluorescence detction (HPLC-FD) to simultaneously quantify COR, adenosine and dA. Pre-column derivatization with chloroacetaldehyde (CAA) was deployed. The proposed method has a limit of detection at the nM level for COR and adenosine, and is far more sensitive than the methods previously deveopled for COR determination. Using the present method, caterpillar fungi were analyzed as model food samples. The analysis revealed that COR was present in cordyceps militaris and cordyceps flowers in a concentration range from 0.314 to 0.735 mg/g, but not in cordyceps sinensis (C. sinensis), a natural and the priciest caterpillar fungus. These results suggest that the profile of active ingredients in C. sinensis has been wrongly claimed for many years. This finding was also supported by the results from further HPLC-MS/MS analyses.

High-throughput screening of the nucleosides and nucleotides using characteristic structural fragments fusion

Cordyceps sinensis is a traditional Chinese food. A high-throughput screening and quantitative method based on hydrophilic interaction chromatography coupled to quadrupole/Orbitrap high resolution mass spectrometry has been proposed for the joint measurement of nucleosides and their corresponding nucleotides in thirty-two Cordyceps sinensis samples. A total of thirty-two natural samples from six regions were enrolled. A multiple-step analysis strategy, including features extraction, noise level evaluation, mass shift correction and suspect spectral library spectra searching, was employed to discover, identify and validate the nucleosides and nucleotides. The remaining unknown compounds were identified with the characteristic structural fragments. The on-line dispersive solid-phase extraction system eliminates human-based steps errors and affords superior method reproducibility in the presence of hexafluoro-2-propanol and diethylamine as hydrophilic ion-pairing reagents. In view of the great difference of the quality, this high coverage confirmation strategy is of great reference value to the future quantitative analysis of potential nucleosides and nucleotides. Nucleosides and nucleotides ingredients could be considered as origins and quality assessment index of C. sinensis.

The effect of fermentation conditions on the structure and anti-tumor activity of polysaccharides from Cordyceps gunnii

This study investigates the effect of fermentation conditions on the structure and anti-tumor activity of intracellular polysaccharides (IPS) of Cordyceps gunnii (C. gunnii) in submerged fermentation. The environmental and nutritional conditions are determined in a shaker flask by a single factor test. The inhibition of IPS on S180 cells was as an optimization index. The results show that the optimal fermentation conditions of C. gunnii are an initial pH value of 6, a temperature of 25 °C, a rotation speed of 150 rpm, 4% glucose, and 1.0% peptone. Under these conditions, the macro molecular weight (M w) polysaccharide content and anti-tumor activity of IPS are significantly higher than that in the basal culture medium. GC, HPGPC, periodate oxidation-Smith degradation, NMR, and FT-IR determine the structural characteristics of CPS-JC and CPS-YH (pure IPS cultured in basal culture medium and optimal culture medium, respectively). The results indicate that CPS-JC is mainly composed of α-d-glucans, whereas CPS-YH primarily contain α-d-glucans with a trace amount of β-d-glucans.

Comprehensive evaluation of wild Cordyceps cicadae from different geographical origins by TOPSIS method based on the macroscopic infrared spectroscopy (IR) fingerprint

Cordyceps cicadae is an entomogenous fungus that has been used as a valuable traditional Chinese herbal tonic, however, it can be difficult to discern the false from the genuine. In this study, the macroscopic IR fingerprint methods containing Fourier transform infrared spectroscopy (FT-IR) and second derivative infrared spectroscopy (SD-IR) were used to elucidate wild C. cicadae. The TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) method was used to comprehensively evaluate C. cicadae from different geographical origins based on the macroscopic infrared spectroscopy (IR) fingerprint. The FT-IR spectra of C. cicadae exhibited the major characteristics of the absorptive peaks of carbohydrates, lipids and nucleosides at the position of 3291, 2925, 2845, 1651, 1547, 1455, 1080 and 950 cm^-1. The high resolution of SD-IR further amplified the difference and revealed the potentially characteristic IR absorption spectrum. TOPSIS evaluation showed that C. cicadae from Anhui possess the strongest intensity of absorption bands among all the samples. Notably, FT-IR combined with SD-IR can effectively reveal the overall chemical components without damaging medicinal materials, and TOPSIS methods can provide a novel scientific evidence for comprehensively assessing different origins of wild C. cicadae.

Preparation of titanium ion functionalized polydopamine coated ferroferric oxide core-shell magnetic particles for selective extraction of nucleotides from Cordyceps and Lentinus edodes

In this study, a titanium ion (Ti⁴⁺) functionalized polydopamine coated ferroferric oxide (Fe₃O₄@PDA@Ti⁴⁺) core-shell magnetic particle was prepared for the selective extraction of nucleotides. Firstly, different metal ions including Ti⁴⁺, Zr⁴⁺, Fe³⁺, Al³⁺, Cu²⁺, Zn²⁺, Ni²⁺ and Mg²⁺ were respectively immobilized onto Fe₃O₄@PDA particles and their extraction efficiency for five nucleotides [cytidine-5'-monophosphate (CMP), uridine-5'-monophosphate (UMP), guanosine-5'-monophosphate (GMP), thymidine-5'-monophosphate (TMP) and adenosine-5'-monophosphate (AMP)] were compared. Among these prepared materials, Fe₃O₄@PDA@Ti⁴⁺, which exhibited the highest extraction efficiency for nucleotides, was further characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray spectroscopy. After being optimized of the extraction parameters including adsorbent amounts, extraction time, extraction temperature, type and concentration of the eluent, the prepared Fe₃O₄@PDA@Ti⁴⁺ magnetic particles were successfully applied for the selective extraction and determination of CMP, UMP, GMP, TMP and AMP in Cordyceps and Lentinus edodes. Good linearity (varying from 0.063 to 19.000 μg/mL, R² > 0.999) and low limit of detection (LODs) (ranging between 0.0047 and 0.0141 μg/mL) for target analytes were achieved. These results demonstrated that the synthesized material in this study had potential for selective extraction of phosphorylated small molecular compounds in complicated matrix.

Characterization of Humic Substances in the Soils of Ophiocordyceps sinensis Habitats in the Sejila Mountain, Tibet: Implication for the Food Source of Thitarodes Larvae

Humic substances in soil are considered to be an alternative food to the tender plant roots for Thitarodes larvae in the habitats of Ophiocordyceps sinensis in the Qinghai-Tibetan Plateau. However, there is no report involving the evaluation of their potential as a food source from the composition and structure of habitat soils. In this work, the composition and structure of humic substances in habitat soils from the Sejila Mountain, Tibet were characterized by diverse techniques for evaluating the nutritional value and possibility of humus as the food source for Thitarodes larvae. Fourier transform infrared spectroscopy revealed that humic acid may possess superior ability to provide the molecular segments for biosynthesizing lipids more than other humic fractions. Combining with the analysis of solid-state 13C nuclear magnetic resonance spectrum, the fractions of hydrophobic fulvic acid and hydrophilic fulvic acid are further considered as a potential food source for Thitarodes larvae. Overall, humic substances in habitat soils are rich in the molecular segments for biosynthesizing lipids and other important nutrients, which may provide the energy and material sources for maintaining the survival of Thitarodes larvae in the absence of tender plant roots, particularly in the annual cold winter. Combining with the evidence of physico-chemical parameters of habitat soils and stable carbon isotopic composition of major tender plant roots in the Sejila Mountain, the composition and structure of humic substances in habitat soils may provide a novel idea for the eco-friendly and semi-wild cultivation of Thitarodes larvae with low cost.

Extract of Paecilomyces hepiali mycelia induces lipolysis through PKA-mediated phosphorylation of hormone-sensitive lipase and ERK-mediated downregulation of perilipin in 3T3-L1 adipocytes

Background

Cordyceps sinensis has been used for centuries in China as one of the most valued herbal medicine and tonic food. Paecilomyces hepiali, a fungal strain isolated from natural C. sinensis, has been used widely as a substitute of C. sinensis in medicine and health food. P. hepiali has been reported to have various pharmaceutical benefits, including triglyceride-lowing activity. However, its effects on triglyceride metabolism in adipocytes remain unknown. The purpose of the present study was to evaluate the effect of P. hepiali mycelia on adipocyte lipolysis and to clarify the underlying mechanisms.

Methods

The fully differentiated 3T3-L1 adipocytes were treated with methanol extract of Paecilomyces hepiali mycelia (PHME). Contents of glycerol released into the culture medium and intracellular triglyceride were measured as indices of lipolysis using glycerol assay kit and Oil red O staining, respectively. Then, effects of PHME on the main lipases or kinases involved in lipolysis regulation were investigated. Protein expression of adipose triglyceride lipase (ATGL) and perilipin, as well as phosphorylation of hormone-sensitive lipase (HSL), AMP-activated protein kinase (AMPK), and mitogen-activated protein kinases (MAPKs) were determined by western blotting. Moreover, nucleosides, important constituents of PHME, were analyzed using high performance liquid chromatography (HPLC).

Results

Treatment with PHME led to a significant increase in glycerol release thereby reduced intracellular triglyceride accumulation in fully differentiated adipocytes. PHME upregulated protein kinase (PK) A-mediated phosphorylation of HSL at serine residues of 563 and 660. Meanwhile, PHME treatment also upregulated phosphorylation of extracellular signal-regulated kinase (ERK), and downregulated the protein level of perilipin. Pretreatment with the PKA inhibitor, H89, blunted the PHME-induced lipolysis and the phosphorylation of HSL (Ser 563 and 660). Moreover, pretreatment with ERK inhibitor, PD98059, weakened the PHME-caused glycerol release and downregulation of perilipin expression. HPLC analysis indicated there were adenosine, cordycepin, uridine and vernine in PHME.

Conclusions

Our results showed that PHME significantly induced lipolysis in 3T3-L1 adipocytes, which is mainly mediated by activation of HSL through PKA pathway and by downregulation of perilipin through activation of ERK pathway.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2389-0) contains supplementary material, which is available to authorized users.

Multiuse of Bar-HRM for Ophiocordyceps sinensis identification and authentication

Bar-HRM is a hybrid method which combines DNA barcoding and High Resolution Melting analysis. It has proven to be a fast, cost-effective and reliable molecular approach for species identification and authentication. Here, three aspects of the use of Bar-HRM are focused on. First, Bar-HRM is used to discriminate between closely related Ophiocordyceps species. Second, identification of an unknown powder that is claimed to be Ophiocordyceps species using Bar-HRM. Third, authenticating the O. sinensis products sold on the market by the Bar-HRM. Results from HRM analyses with ITS primers shows that the two Ophiocordyceps species (Ophiocordyceps sinensis and Ophiocordyceps militaris) were easily differentiated. Also, an unknown sample was able to be identified in less time compared with using DNA barcoding alone. In addition, the substitution or adulteration of O. sinensis products sold on market was detected via Bar-HRM. The substitution or adulteration of inferior Ophiocordyceps species, particularly O. militaris in high price O. sinensis products has been a concern throughout Asia. Based on our results, the Bar-HRM was again proved to be a promising tool for species identification and authentication.

A comparative proteomic characterization and nutritional assessment of naturally- and artificially-cultivated Cordyceps sinensis

Cordyceps sinensis has gained increasing attention due to its nutritional and medicinal properties. Herein, we employed label-free quantitative mass spectrometry to explore the proteome differences between naturally- and artificially-cultivated C. sinensis. A total of 22,829 peptides with confidence ≥95%, corresponding to 2541 protein groups were identified from the caterpillar bodies/stromata of 12 naturally- and artificially-cultivated samples of C. sinensis. Among them, 165 proteins showed significant differences between the samples of natural and artificial cultivation. These proteins were mainly involved in energy production/conversion, amino acid transport/metabolism, and transcription regulation. The proteomic results were confirmed by the identification of 4 significantly changed metabolites, thus, lysine, threonine, serine, and arginine via untargeted metabolomics. The change tendencies of these metabolites were partly in accordance with changes in abundance of the proteins, which was upstream of their synthetic pathways. In addition, the nutritional value in terms of the levels of nucleosides, nucleotides, and adenosine between the artificially- and naturally-cultivated samples was virtually same. These proteomic data will be useful for understanding the medicinal value of C. sinensis and serve as reference for its artificial cultivation.

SIGNIFICANCE

C. sinensis is a precious and valued medicinal product, the current basic proteome dataset would provide useful information to understand its development/infection processes as well as help to artificially cultivate it. This work would also provide basic proteome profile for further study of C. sinensis.