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Xin Liu - One of the best experts on this subject based on the ideXlab platform.
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comparative metabolic profiling of Ophiocordyceps Sinensis and its cultured mycelia using gc ms
Food Research International, 2020Co-Authors: Jianshuang Zhang, Xin Zhong, Haizhen Wang, Xin LiuAbstract:Abstract 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.
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profile of Ophiocordyceps Sinensis transcriptome and differentially expressed genes in three different mycelia sclerotium and fruiting body developmental stages
Fungal Biology, 2018Co-Authors: Xin Zhong, Guren Zhang, Haizhen Wang, Danhong Lian, Yimei Zheng, Sha Zhou, Wei Zhou, Xin LiuAbstract:Abstract Ophiocordyceps Sinensis, a Chinese complementary and alternative medicine (CAM), is an entomopathogenic, fungus, parasitizing larvae of the moth genus Thitarodes. It has three stages of the life cycle, i.e., the anamorph mycelia prior to infection (Cm_Os), the mycelia sclerotium forming in the caterpillar (Te_Ca), and the fruiting bodies or stromata (Te_St). Characterization of the O. Sinensis transcriptome among these stages could provide a better understanding of the underlying biology processes. Transcriptomics of the O. Sinensis asexual mycelia and hyphae in deceased caterpillars and perithecial stroma was assessed by using Illumina HiSeq™ 2000 technology. A total of 14,922 unigenes were identified and categorized into 46 sub-categories under three gene ontology categories (“biological process”, “cellular component”, and “molecular function”). Of these genes, 5520 were differentially expressed among the libraries of these three groups of samples (P
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a polycephalomyces hyperparasite of Ophiocordyceps Sinensis leads to shortened duration of production and reduced numbers of host ascospores
Fungal Ecology, 2016Co-Authors: Xin Zhong, Guren Zhang, Qingyun Peng, Jianshuang Zhang, Xutian Kan, Xin LiuAbstract:Ophiocordyceps Sinensis, an entomopathogenic fungus of the Tibetan Plateau is one of the most valuable traditional Chinese medicines. A fungal pathogen of O. Sinensis, Polycephalomyces sp. GIMCC 3.570 (isolate 2010A-0818) was characterized by morphology, related to sequences of six genes (SSU, ITS, LSU, TEF1-α, RPB1 and ATP6) found in a BLAST search and five genes (SSU, LSU, TEF1, RPB1 and RPB2) by phylogenetic analysis using maximum parsimony, maximum likelihood and Bayesian methods. The results strongly support placement of P. sp. GIMCC 3.570 in the genus Polycephalomyces. To determine the influence of P. sp. GIMCC 3.570 on the reproduction of its host, 30 artificially infected O. Sinensis samples were compared with 30 uninfected controls. In the infected fungus, the life span of the stroma was significantly shorter and significantly fewer ascospores were produced compared with uninfected O. Sinensis (p < 0.01).
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transcriptome analysis of Ophiocordyceps Sinensis before and after infection of thitarodes larvae
Fungal Biology, 2016Co-Authors: Xin Zhong, Guren Zhang, Xutian Kan, Xin LiuAbstract:Ophiocordyceps Sinensis, also referred to as the Chinese caterpillar fungus, is a rare entomopathogenic fungus found in the Qinghai-Tibetan Plateau that is used as a traditional Chinese medicine. O. Sinensis parasitizes the larvae of the ghost moth Thitarodes. Characterization of the transcriptome of O. Sinensis before and after host infection may provide novel insight into the process by which the fungus interacts with Thitarodes and may help researchers understand how to sustain this valuable resource. In this study, we performed RNA-sequencing (RNA-seq) using Illumina HiSeqTM 2000 technology to generate gene expression profiles of two developmental stages of O. Sinensis. Thread-like hyphae before infection and yeast-like hyphal bodies after infection of host larvae were collected for transcriptome analysis. We found that 1640 genes were differentially expressed (q-value < 0.05), of which 818 were upregulated (49.878 %) and 822 were downregulated (50.122 %). Gene ontology (GO) analysis revealed that the differentially expressed genes (DEGs) were especially enriched in terms associated with Biological Process and Molecular Function. Several genes encoding transporter and permease proteins, three glycoside hydrolases, two mycotoxin-related proteins, an antigen protein, and an allergen were identified as being significantly up- or downregulated. Collectively, our findings provide a novel resource for understanding O. Sinensis during two critical developmental stages, and offer the opportunity to further investigate the functional mechanisms underlying these stage-specific molecular differences.
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de novo transcriptome analysis of thitarodes jiachaensis before and after infection by the caterpillar fungus Ophiocordyceps Sinensis
Gene, 2016Co-Authors: Xin Zhong, Guren Zhang, Xutian Kan, Hongxia Sun, Xin LiuAbstract:Thitarodes jiachaensis is a host species of the pathogenic caterpillar fungus Ophiocordyceps Sinensis, which is a fungus with broad medical effects and great economic value. Curated genomic information on Thitarodes is still limited, and the interaction between host Thitarodes larvae and O. Sinensis during infection is incompletely understood. In this study, we performed transcriptome sequencing for T. jiachaensis before and after O. Sinensis infection using the Illumina sequencing platform, and we identified the transcripts associated with the defense response of T. jiachaensis upon O. Sinensis infection. A total of 161,804 transcripts and 94,827 unigenes for T. jiachaensis were obtained from 26.62-Gb clean reads, and 35.03% of all the unigenes were annotated in current databases. The expression of 1581 genes was significantly altered following infection; among them, 928 (58.70%) were up-regulated and 653 (41.30%) were down-regulated. Genes encoding physical barriers such as cuticle proteins and peritrophic matrix proteins, antimicrobial peptides (AMPs), pattern recognition receptors (PRRs), and enzymes in the proteolytic cascade were predicted to be involved in the response of T. jiachaensis to O. Sinensis infection. Together, these data provide a valuable genomic resource for further studies of Thitarodes and increase our understanding of the host-pathogen interaction that occurs between Thitarodes and O. Sinensis.
Ping Zhang - One of the best experts on this subject based on the ideXlab platform.
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discriminatory power evaluation of nuclear ribosomal rna barcoding sequences through Ophiocordyceps Sinensis related samples
Frontiers in Microbiology, 2018Co-Authors: Ping Zhang, Feng Wei, Shenghui Cui, Xiu Ren, Shuai Kang, Bin LiuAbstract:Since the cost of Ophiocordyceps Sinensis has increased dramatically and the counterfeits may have adverse effect to health, a rapid and precise species-level DNA barcoding identification system could be a potent approach and significantly enhance the regulatory capacity. The discrimination power of three subunits sequences from nuclear ribosomal RNA gene cluster were determined by Simpson's index of discrimination using 43 wild O. Sinensis fruiting bodies, pure cultures, commercial mycelium fermented powder and counterfeits. The internal transcribed spacer (ITS) sequences showed the highest variance and discrimination power among 43 samples, as determined by Simpson's index of discrimination (D = 0.972), followed by large subunit (LSU; D = 0.963) and small subunit (SSU; D = 0.921). ITS-2 sequences showed the highest discrimination power for 43 samples among ITS-1, ITS-2, and 5.8S region of ITS sequences. All O. Sinensis samples were grouped into a unique ITS sequence cluster under 95% similarity and two O. Sinensis samples and six non-O. Sinensis samples showed false claims. Our data showed that the ITS region could provide accurate species identification for O. Sinensis samples, especially when macroscopic and microscopic method could not be applied in the highly processed commercial products. Since the authentication of O. Sinensis related products is essential to ensure its safety and efficacy, identification of O. Sinensis through ITS sequence comparison or unique PCR amplification of the species specific target, such as the ITS region, should be considered in the next revision of Chinese pharmacopeia.
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identification of Ophiocordyceps Sinensis and its artificially cultured Ophiocordyceps mycelia by ultra performance liquid chromatography orbitrap fusion mass spectrometry and chemometrics
Molecules, 2018Co-Authors: Ping Zhang, Feng Wei, Xianlong Cheng, Guifeng Zhang, Bin LiuAbstract:Since the cost of Ophiocordyceps Sinensis, an important fungal drug used in Chinese medicine, has increased dramatically, and the counterfeits may have adverse health effects, a rapid and precise marker using the peptide mass spectrometry identification system could significantly enhance the regulatory capacity. In this study, we determined the marker peptides in the digested mixtures of fungal proteins in wild O. Sinensis fruiting bodies and various commercially available mycelium fermented powders using ultra-performance liquid chromatography/Orbitrap Fusion mass spectrometry coupled with chemometrics. The results indicated the following marker peptides: TLLEAIDSIEPPK (m/z 713.39) was identified in the wild O. Sinensis fruiting body, AVLSDAITLVR (m/z 579.34) was detected in the fermented O. Sinensis mycelium powder, FAELLEK (m/z 849.47) was found in the fermented Ophiocordyceps mycelium powder, LESVVTSFTK (m/z 555.80) was discovered in the artificial Ophiocordyceps mycelium powder, and VPSSAVLR (m/z 414.75) was observed in O. mortierella mycelium powder. In order to verify the specificity and applicability of the method, the five marker peptides were synthesized and tested on all samples. All in all, to the best of our knowledge, this is the first time that mass spectrometry has been employed to detect the marker peptides of O.Sinensis and its related products.
Xingzhong Liu - One of the best experts on this subject based on the ideXlab platform.
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the intronic minisatellite osmin1 within a serine protease gene in the chinese caterpillar fungus Ophiocordyceps Sinensis
Applied Microbiology and Biotechnology, 2016Co-Authors: Yongjie Zhang, Shu Zhang, Junxiu Hou, Georg Hausner, Xingzhong LiuAbstract:Repetitive DNA sequences make up a significant portion of all genomes and may occur in intergenic, regulatory, coding, or even intronic regions. Partial sequences of a serine protease gene csp1 was previously used as a population genetic marker of the Chinese caterpillar fungus Ophiocordyceps Sinensis, but its first intron region was excluded due to ambiguous alignment. Here in this study, we report the presence of a minisatellite OsMin1 within this intron, where a 20(19)-bp repeat motif is duplicated two to six times in different isolates. Fourteen intron alleles and 13 OsMin1 alleles were identified among 125 O. Sinensis samples distributed broadly on the Tibetan Plateau. Two OsMin1 alleles were prevalent, corresponding to either two or five repeats of the core sequence motif. OsMin1 appears to be a single locus marker in the O. Sinensis genome, but its origin is undetermined. Abundant recombination signals were detected between upstream and downstream flanking regions of OsMin1, suggesting that OsMin1 mutate by unequal crossing over. Geographic distribution, fungal phylogeny, and host insect phylogeny all significantly affected intron distribution patterns but with the greatest influence noted for fungal genotypes and the least for geography. As far as we know, OsMin1 is the first minisatellite found in O. Sinensis and the second found in fungal introns. OsMin1 may be useful in designing an efficient protocol to discriminate authentic O. Sinensis from counterfeits.
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on the reliability of dna sequences of Ophiocordyceps Sinensis in public databases
Journal of Industrial Microbiology & Biotechnology, 2013Co-Authors: Yongjie Zhang, Xingzhong Liu, Shu Zhang, Hong Zhang, Diansheng LiuAbstract:Some DNA sequences in the International Nucleotide Sequence Databases (INSD) are erroneously annotated, which has lead to misleading conclusions in publications. Ophiocordyceps Sinensis (syn. Cordyceps Sinensis) is a fungus endemic to the Tibetan Plateau, and more than 100 populations covering almost its distribution area have been examined by us over recent years. In this study, using the data from authentic materials, we have evaluated the reliability of nucleotide sequences annotated as O. Sinensis in the INSD. As of October 15, 2012, the INSD contained 874 records annotated as O. Sinensis, including 555 records representing nuclear ribosomal DNA (63.5 %), 197 representing protein-coding genes (22.5 %), 92 representing random markers with unknown functions (10.5 %), and 30 representing microsatellite loci (3.5 %). Our analysis indicated that 39 of the 397 internal transcribed spacer entries, 27 of the 105 small subunit entries, and five of the 53 large subunit entries were incorrectly annotated as belonging to O. Sinensis. For protein-coding sequences, all records of serine protease genes, the mating-type gene MAT1-2-1, the DNA lyase gene, the two largest subunits of RNA polymerase II, and elongation factor-1α gene were correct, while 14 of the 73 β-tubulin entries were indeterminate. Genetic diversity analyses using those sequences correctly identified as O. Sinensis revealed significant genetic differentiation in the fungus although the extent of genetic differentiation varied with the gene. The relationship between O. Sinensis and some other related fungal taxa is also discussed.
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determining novel molecular markers in the chinese caterpillar fungus Ophiocordyceps Sinensis by screening a shotgun genomic library
Applied Microbiology and Biotechnology, 2012Co-Authors: Yongjie Zhang, Shu Zhang, Feirong Bai, Xingzhong LiuAbstract:The Chinese caterpillar fungus Ophiocordyceps Sinensis, endemic to alpine regions on the Tibetan Plateau, is one of the most valuable medicinal fungi in the world. Genetic differentiation within this fungus was observed; however, due to lack of highly efficient molecular markers, the overall genetic structure of this fungus has not been clarified. In this study, a shotgun genomic library of O. Sinensis was constructed, and >181,848 nt were analyzed from >250 random clones. Primers from 33 sequenced fragments were then designed to amplify O. Sinensis samples collected from widely separated regions on the Tibetan Plateau. Ten of the 33 fragments had no amplification or poor sequencing quality from all or certain samples. Sequence variations of the remaining 23 fragments among different samples were investigated in detail. Three fragments (OSRC14, OSRC19, and OSRC32) were the most variable with 7–43 single-nucleotide polymorphism (SNP) sites, representing the SNP frequency of 1.2–6.7 % per nucleotide site. These three fragments have the potential to be useful molecular markers for studying the population genetics of O. Sinensis. These results also showed that constructing and screening a shotgun genomic library was an efficient approach to identify novel molecular markers from non-model organisms.
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Ophiocordyceps Sinensis the flagship fungus of china terminology life strategy and ecology
Mycology, 2012Co-Authors: Yongjie Zhang, Chengshu Wang, Xingzhong LiuAbstract:The Chinese caterpillar fungus, Ophiocordyceps Sinensis (syn. Cordyceps Sinensis), is one of the most famous and perhaps the most expensive fungal species in the world. Its biology largely remains a secret, and its commercial cultivation is still a dream. Owing to its medicinal, economic, social and ecological importance, and its limited distribution mainly in China, O. Sinensis is herein nominated as the national fungus of China and the fungus of the year (2012) for the journal Mycology. To clarify the confusion, a standard nomenclature is proposed and recommended in this paper for a comprehensive understanding of the terms related to Cordyceps sensu lato and O. Sinensis. We also review recent research on the life cycle and distribution of this fungus, parasitism of ghost moths by the fungus, the microbial community of natural Chinese cordyceps and its insect hosts, as well as the secondary metabolites produced by the fungi isolated from natural Chinese cordyceps. By taking advantage of various expertise...
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high diversity of the fungal community structure in naturally occurring Ophiocordyceps Sinensis
PLOS ONE, 2010Co-Authors: Yongjie Zhang, Shu Zhang, Mu Wang, Fengyan Bai, Xingzhong LiuAbstract:Background Ophiocordyceps Sinensis (syn. Cordyceps Sinensis), which is a parasite of caterpillars and is endemic to alpine regions on the Tibetan Plateau, is one of the most valuable medicinal fungi in the world. “Natural O. Sinensis specimens” harbor various other fungi. Several of these other fungi that have been isolated from natural O. Sinensis specimens have similar chemical components and/or pharmaceutical effects as O. Sinensis. Nevertheless, the mycobiota of natural O. Sinensis specimens has not been investigated in detail. Methodology/Principal Findings Based on the technique of PCR-single-strand conformation polymorphism (PCR-SSCP), the mycobiota of three different sections (stromata, sclerotia, and mycelial cortices) from natural O. Sinensis specimens were investigated using both culture-dependent and -independent methods. For the culture-dependent method, 572 fungal strains were isolated, and 92 putative operational taxonomic units (OTUs) were identified from 226 sequenced strains with the threshold of 97%. For the culture-independent method, 490 fungal clones were identified from about 3000 clones of ITS fragments from the whole-community DNA; based on PCR-SSCP analyses, 266 of these clones were selected to be sequenced, and 118 putative OTUs were detected. The overwhelming majority of isolates/clones and OTUs were detected from mycelial cortices; only a few were detected from stromata and sclerotia. The most common OTUs detected with both methods belonged to Ascomycota; however, only 13 OTUs were detected simultaneously by both methods. Potential novel lineages were detected by each of the two methods. Conclusions/Significance A great number of fungal species present in the mycobiota of naturally-occurring O. Sinensis specimens were detected, and many of them may represent undescribed lineages. That only a few of the same OTUs were detected by both methods indicated that different methods should be used. This study increased our understanding about the fungal community structure of this valuable medicinal herb.
Yongjie Zhang - One of the best experts on this subject based on the ideXlab platform.
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the intronic minisatellite osmin1 within a serine protease gene in the chinese caterpillar fungus Ophiocordyceps Sinensis
Applied Microbiology and Biotechnology, 2016Co-Authors: Yongjie Zhang, Shu Zhang, Junxiu Hou, Georg Hausner, Xingzhong LiuAbstract:Repetitive DNA sequences make up a significant portion of all genomes and may occur in intergenic, regulatory, coding, or even intronic regions. Partial sequences of a serine protease gene csp1 was previously used as a population genetic marker of the Chinese caterpillar fungus Ophiocordyceps Sinensis, but its first intron region was excluded due to ambiguous alignment. Here in this study, we report the presence of a minisatellite OsMin1 within this intron, where a 20(19)-bp repeat motif is duplicated two to six times in different isolates. Fourteen intron alleles and 13 OsMin1 alleles were identified among 125 O. Sinensis samples distributed broadly on the Tibetan Plateau. Two OsMin1 alleles were prevalent, corresponding to either two or five repeats of the core sequence motif. OsMin1 appears to be a single locus marker in the O. Sinensis genome, but its origin is undetermined. Abundant recombination signals were detected between upstream and downstream flanking regions of OsMin1, suggesting that OsMin1 mutate by unequal crossing over. Geographic distribution, fungal phylogeny, and host insect phylogeny all significantly affected intron distribution patterns but with the greatest influence noted for fungal genotypes and the least for geography. As far as we know, OsMin1 is the first minisatellite found in O. Sinensis and the second found in fungal introns. OsMin1 may be useful in designing an efficient protocol to discriminate authentic O. Sinensis from counterfeits.
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on the reliability of dna sequences of Ophiocordyceps Sinensis in public databases
Journal of Industrial Microbiology & Biotechnology, 2013Co-Authors: Yongjie Zhang, Xingzhong Liu, Shu Zhang, Hong Zhang, Diansheng LiuAbstract:Some DNA sequences in the International Nucleotide Sequence Databases (INSD) are erroneously annotated, which has lead to misleading conclusions in publications. Ophiocordyceps Sinensis (syn. Cordyceps Sinensis) is a fungus endemic to the Tibetan Plateau, and more than 100 populations covering almost its distribution area have been examined by us over recent years. In this study, using the data from authentic materials, we have evaluated the reliability of nucleotide sequences annotated as O. Sinensis in the INSD. As of October 15, 2012, the INSD contained 874 records annotated as O. Sinensis, including 555 records representing nuclear ribosomal DNA (63.5 %), 197 representing protein-coding genes (22.5 %), 92 representing random markers with unknown functions (10.5 %), and 30 representing microsatellite loci (3.5 %). Our analysis indicated that 39 of the 397 internal transcribed spacer entries, 27 of the 105 small subunit entries, and five of the 53 large subunit entries were incorrectly annotated as belonging to O. Sinensis. For protein-coding sequences, all records of serine protease genes, the mating-type gene MAT1-2-1, the DNA lyase gene, the two largest subunits of RNA polymerase II, and elongation factor-1α gene were correct, while 14 of the 73 β-tubulin entries were indeterminate. Genetic diversity analyses using those sequences correctly identified as O. Sinensis revealed significant genetic differentiation in the fungus although the extent of genetic differentiation varied with the gene. The relationship between O. Sinensis and some other related fungal taxa is also discussed.
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determining novel molecular markers in the chinese caterpillar fungus Ophiocordyceps Sinensis by screening a shotgun genomic library
Applied Microbiology and Biotechnology, 2012Co-Authors: Yongjie Zhang, Shu Zhang, Feirong Bai, Xingzhong LiuAbstract:The Chinese caterpillar fungus Ophiocordyceps Sinensis, endemic to alpine regions on the Tibetan Plateau, is one of the most valuable medicinal fungi in the world. Genetic differentiation within this fungus was observed; however, due to lack of highly efficient molecular markers, the overall genetic structure of this fungus has not been clarified. In this study, a shotgun genomic library of O. Sinensis was constructed, and >181,848 nt were analyzed from >250 random clones. Primers from 33 sequenced fragments were then designed to amplify O. Sinensis samples collected from widely separated regions on the Tibetan Plateau. Ten of the 33 fragments had no amplification or poor sequencing quality from all or certain samples. Sequence variations of the remaining 23 fragments among different samples were investigated in detail. Three fragments (OSRC14, OSRC19, and OSRC32) were the most variable with 7–43 single-nucleotide polymorphism (SNP) sites, representing the SNP frequency of 1.2–6.7 % per nucleotide site. These three fragments have the potential to be useful molecular markers for studying the population genetics of O. Sinensis. These results also showed that constructing and screening a shotgun genomic library was an efficient approach to identify novel molecular markers from non-model organisms.
-
Ophiocordyceps Sinensis the flagship fungus of china terminology life strategy and ecology
Mycology, 2012Co-Authors: Yongjie Zhang, Chengshu Wang, Xingzhong LiuAbstract:The Chinese caterpillar fungus, Ophiocordyceps Sinensis (syn. Cordyceps Sinensis), is one of the most famous and perhaps the most expensive fungal species in the world. Its biology largely remains a secret, and its commercial cultivation is still a dream. Owing to its medicinal, economic, social and ecological importance, and its limited distribution mainly in China, O. Sinensis is herein nominated as the national fungus of China and the fungus of the year (2012) for the journal Mycology. To clarify the confusion, a standard nomenclature is proposed and recommended in this paper for a comprehensive understanding of the terms related to Cordyceps sensu lato and O. Sinensis. We also review recent research on the life cycle and distribution of this fungus, parasitism of ghost moths by the fungus, the microbial community of natural Chinese cordyceps and its insect hosts, as well as the secondary metabolites produced by the fungi isolated from natural Chinese cordyceps. By taking advantage of various expertise...
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high diversity of the fungal community structure in naturally occurring Ophiocordyceps Sinensis
PLOS ONE, 2010Co-Authors: Yongjie Zhang, Shu Zhang, Mu Wang, Fengyan Bai, Xingzhong LiuAbstract:Background Ophiocordyceps Sinensis (syn. Cordyceps Sinensis), which is a parasite of caterpillars and is endemic to alpine regions on the Tibetan Plateau, is one of the most valuable medicinal fungi in the world. “Natural O. Sinensis specimens” harbor various other fungi. Several of these other fungi that have been isolated from natural O. Sinensis specimens have similar chemical components and/or pharmaceutical effects as O. Sinensis. Nevertheless, the mycobiota of natural O. Sinensis specimens has not been investigated in detail. Methodology/Principal Findings Based on the technique of PCR-single-strand conformation polymorphism (PCR-SSCP), the mycobiota of three different sections (stromata, sclerotia, and mycelial cortices) from natural O. Sinensis specimens were investigated using both culture-dependent and -independent methods. For the culture-dependent method, 572 fungal strains were isolated, and 92 putative operational taxonomic units (OTUs) were identified from 226 sequenced strains with the threshold of 97%. For the culture-independent method, 490 fungal clones were identified from about 3000 clones of ITS fragments from the whole-community DNA; based on PCR-SSCP analyses, 266 of these clones were selected to be sequenced, and 118 putative OTUs were detected. The overwhelming majority of isolates/clones and OTUs were detected from mycelial cortices; only a few were detected from stromata and sclerotia. The most common OTUs detected with both methods belonged to Ascomycota; however, only 13 OTUs were detected simultaneously by both methods. Potential novel lineages were detected by each of the two methods. Conclusions/Significance A great number of fungal species present in the mycobiota of naturally-occurring O. Sinensis specimens were detected, and many of them may represent undescribed lineages. That only a few of the same OTUs were detected by both methods indicated that different methods should be used. This study increased our understanding about the fungal community structure of this valuable medicinal herb.
Bin Liu - One of the best experts on this subject based on the ideXlab platform.
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discriminatory power evaluation of nuclear ribosomal rna barcoding sequences through Ophiocordyceps Sinensis related samples
Frontiers in Microbiology, 2018Co-Authors: Ping Zhang, Feng Wei, Shenghui Cui, Xiu Ren, Shuai Kang, Bin LiuAbstract:Since the cost of Ophiocordyceps Sinensis has increased dramatically and the counterfeits may have adverse effect to health, a rapid and precise species-level DNA barcoding identification system could be a potent approach and significantly enhance the regulatory capacity. The discrimination power of three subunits sequences from nuclear ribosomal RNA gene cluster were determined by Simpson's index of discrimination using 43 wild O. Sinensis fruiting bodies, pure cultures, commercial mycelium fermented powder and counterfeits. The internal transcribed spacer (ITS) sequences showed the highest variance and discrimination power among 43 samples, as determined by Simpson's index of discrimination (D = 0.972), followed by large subunit (LSU; D = 0.963) and small subunit (SSU; D = 0.921). ITS-2 sequences showed the highest discrimination power for 43 samples among ITS-1, ITS-2, and 5.8S region of ITS sequences. All O. Sinensis samples were grouped into a unique ITS sequence cluster under 95% similarity and two O. Sinensis samples and six non-O. Sinensis samples showed false claims. Our data showed that the ITS region could provide accurate species identification for O. Sinensis samples, especially when macroscopic and microscopic method could not be applied in the highly processed commercial products. Since the authentication of O. Sinensis related products is essential to ensure its safety and efficacy, identification of O. Sinensis through ITS sequence comparison or unique PCR amplification of the species specific target, such as the ITS region, should be considered in the next revision of Chinese pharmacopeia.
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identification of Ophiocordyceps Sinensis and its artificially cultured Ophiocordyceps mycelia by ultra performance liquid chromatography orbitrap fusion mass spectrometry and chemometrics
Molecules, 2018Co-Authors: Ping Zhang, Feng Wei, Xianlong Cheng, Guifeng Zhang, Bin LiuAbstract:Since the cost of Ophiocordyceps Sinensis, an important fungal drug used in Chinese medicine, has increased dramatically, and the counterfeits may have adverse health effects, a rapid and precise marker using the peptide mass spectrometry identification system could significantly enhance the regulatory capacity. In this study, we determined the marker peptides in the digested mixtures of fungal proteins in wild O. Sinensis fruiting bodies and various commercially available mycelium fermented powders using ultra-performance liquid chromatography/Orbitrap Fusion mass spectrometry coupled with chemometrics. The results indicated the following marker peptides: TLLEAIDSIEPPK (m/z 713.39) was identified in the wild O. Sinensis fruiting body, AVLSDAITLVR (m/z 579.34) was detected in the fermented O. Sinensis mycelium powder, FAELLEK (m/z 849.47) was found in the fermented Ophiocordyceps mycelium powder, LESVVTSFTK (m/z 555.80) was discovered in the artificial Ophiocordyceps mycelium powder, and VPSSAVLR (m/z 414.75) was observed in O. mortierella mycelium powder. In order to verify the specificity and applicability of the method, the five marker peptides were synthesized and tested on all samples. All in all, to the best of our knowledge, this is the first time that mass spectrometry has been employed to detect the marker peptides of O.Sinensis and its related products.