Chanhua is an important Chinese medicinal cordycipitoid mushroom, however, the names, especially scientific names, have been confused for long period. It is justified that an oldest Chinese name “chanhua” has been used most widely and should be prior to others. Isaria cicadae was named by Miquel based on a Brazilian specimen no longer existent, with incomplete description and simple figure, showing different from chanhua morphologically. Its teleomorph has not been found yet, previously misconnected with Ophiocordyceps sobolifera and Tolypocladium dujiaolongae (=Cordyceps cicadae Shing). Based on literature study, the misuse of O. sobolifera and T. dujiaolongae was clarified and the influence of long-term nomenclatural confusion in Japanese literature was analyzed. The distribution of I. cicadae in China is doubtful, and I. cicadae sp. coll. (species collectiva) is proposed. Taxonomy and nomenclature of chanhua need to be further studied.
Based on the historical changes of the concept of symbiosis, this paper introduces the commonly accepted concept of symbiosis in sense lato. Symbiosis is a symbiotic continuum that includes mutualism, commensalism, and antagonism/parasitism. This paper briefly describes the important achievements of nine times International Symbiosis Society Congress in the past 20 years. Advances in the study and utilization of cellular endosymbiosis, and time, space as well as multiple interaction scale symbiosis are reviewed. In addition, we outline research in some active fields of symbiosis, such as dysbiosis, insect-microbe-insect triangle, the bacterial-fungal interactions (BFI), mycorrhizal fungi-endofungal bacteria (or endobacteria)-plant multipartite symbiosis, as well as metacommunity study and application of the symbiosis-related microbiome. Symbiosis has become the core principle of contemporary biology. It has fundamentally changed some traditional biological concepts, such as the concept of isolated individuality. Genome sequencing and high-throughput RNA analysis revealed important interactions between animals, plants and symbiotic microbes, breaking down hitherto unique boundaries of individual organisms and challenging the definitions of these disciplines. Symbiosis is not only a one-to-one mutualism, but actually a continuous symbiosis of multiple symbiosis modes. The discovery of new relationships, such as the symbiosis triangle of plant-insect- microorganism interaction and the multi-partite consortium of mycorrhizomates-fungus-endophytic bacteria- plants, has pushed the life science to the direction of rapid development. These scientific advances have not only broadened horizons that are vital to the study of genetics, immunology, evolution, development, anatomy and physiology of the biological sciences, but also have a positive impact on the research and development of biological agents in agriculture, the management and regulation of the human microbiome, and the design and management of fermented food and industrial microbial production.
Rhinofacial and rhino-orbital-cerebral mycosis (ROCM) is a fulminant fungal infection with a high mortality rate, mostly caused by fungi in the orders of Mucorales, Entomophthorales and Basidiobolales. Members of the genus Aspergillus are commonly involved in fungal sinusitis. If invading the adjacent nasal, facial and orbital tissues, the fungus may extend to the skull base and/or nervous system and become life-threatening. Due to the lack of specificity of early clinical manifestations, timely diagnosis may be difficult and the rate of misdiagnosis is high. In addition, effective antifungal treatment of Aspergillus spp. deviates considerably from that of other fungi. This article provides a systematic Meta-analysis of the relevant literature in PubMed and the Chinese literature database, and comprehensively summarizes the relevant Aspergillus species causing ROCM, together with their regional distribution, risk factors, clinical manifestations, diagnosis and treatment.
Diaporthe species in China are highly diverse but still mostly unexplored. In this study, Diaporthe specimens were collected from symptomatic leaves in Yunnan Province. Identification was done using combination of morphology and comparison of DNA sequence data of the nuclear ribosomal internal transcribed spacer (ITS), β-tubulin (TUB), partial translation elongation factor-1α (TEF), calmodulin (CAL) and histone H3 (HIS) gene regions. Two new species, viz. D. clausenae and D. theobromatis, were found on Clausena anisata and Theobroma cacao, respectively. They are illustrated and described morphologically and phylogenetic relationships with other Diaporthe species are discussed.
External auditory canal secretion samples were collected from both healthy individuals and patients with fungal otitis externa in Guangdong Province, China. Total DNA extraction was performed, and the bacterial and fungal community structure and diversity were analyzed. The results indicated that pathogenic bacteria were present in the external auditory secretions collected from both infected and healthy individuals. Although fungi were detected in the samples collected from healthy individuals as well, the community structure differed significantly from that in samples collected from infected individuals. With respect to the fungi, the samples collected from healthy individuals primarily contained non-pathogenic basidiomycetes. Aspergillus (phylum: Ascomycota) was the predominant fungal genus present in the samples collected from the infected individuals. The occurrence percentage of pathogenic Aspergillus in 8 out of the 10 samples collected from infected individuals was above 90%. No significant correlation was observed between the changes in the abundances of fungi and bacteria. Mutual dependence between the bacterial and fungal communities was not apparent. Generally, changes in the microbial community structure in the external auditory secretions are an indicator for inflammation. The excessive growth of Aspergillus in the auditory canal is an important cause of external auditory canal fungal disease. Therefore, the maintenance of an external auditory environment that is not conducive to the growth of Aspergillus may serve as an effective step toward the prevention of infection.
Blueberry root rot disease was found for the first time in Qingdao, Shandong Province. The earliest symptoms occurred on root, then the diseased roots became rot and necrotic, and the vascular bundle and bark of rhizomes turned black. As a result, the radication became underdeveloped, the leaves turned yellow and red, and the plant grew poorly. In severe cases, all the leaves fell and the plant died. The pure isolate HMQAU180018 was obtained by tissue isolation method and mycelium segment isolation method. According to the pathogenicity test by Koch’s postulates, morphological and biological characteristics, sequence analyses of ITS and cox I, the pathogen was identified as Pythium irregulare. This is the first report of blueberry root rot caused by P. irregulare in China.
Association between Euops chinensis and its symbiotic fungus Penicillium herquei is a typical attelabid fungiculture. How P. herquei provides nutrition for E. chinensis is unknown. We found that there were abundant appendages of nodular protrusions and networks on the hyphal surface of P. herquei, which might be the nutrient for host weevil. The nutritional requirements of P. herquei indicated mono- and di-saccharides such as glucitol, sucrose, trehalose, and glucose as carbon sources and non-essential amino acids of insect such as tyrosine, glycine, and glutamine as nitrogen sources supported the well growth of P. herquei. High-carbon and optimal carbon source environments can promote production of more appendages on the hyphal surface. The results not only provide evidence of symbiotic fungus nutritional adaptation in the attelabid weevil fungiculture, but also lay the foundation for further revealing the nutritional mechanism of the symbiotic fungus adapting to the leaf rolling weevil.
Moldy core caused by Alternaria spp. is a common fruit disease of apples. The long period of pathogen makes difficulty in observing the exact pathway of infection. The fluorescent labeling is an effective way to solve this kind of problems. Exogenous DNA carrying the GFP gene was inserted into A. alternata genome based on PEG-mediated hyphal protoplast transformation, and a total of 150 transformants was obtained. The transformant NC-1, which had no significant variation in colony morphology, growth rate and pathogenicity, was inoculated on apple floral tissues at full-bloom stage in the field. After 48h the petals, styles, anthers and filaments turned brown and water-stained lesions appeared. After 4d, the floral tissues dried and the flowers dropped down. After 20d, the young fruit became moldy and fell soon. The hyphae covering the lesions were observed obviously as green fluorescence under fluorescence microscope. The result indicated that the PEG-mediated A. alternata hyphal protoplast transformation was successfully constructed, and the fluorescent strain NC-1 could be used for the study of wild infection mechanism of apple moldy core.
Rhizopus arrhizus is widely distributed in nature, important in food fermentation and well-known as opportunistic pathogens. It is diverse in morphology and biochemistry, including three taxonomic varieties (arrhizus, delemar and tonkinensis), four morphological types (arrhizus, delemar, tonkinensis and rouxii) and two biochemical groups (lactic acid, LA; and fumaric-malic acid, FMA). This species is more diverse in DNA molecules. However, the relationship among all these diversities lacks a systematic research. Based on the internal transcribed spacer (ITS), intergenic spacer (IGS) of nuclear ribosomal DNA and single nucleotide polymorphisms (SNPs) extracted from whole-genome resequencing, this study analyzed the phylogeny and population structure of R. arrhizus represented by strains covering the diversities above. Results showed that R. arrhizus was divided into four main phylogenetic clades. The sister clades 1 and 2 constituted the variety delemar, and the other two clades corresponded with the varieties tonkinensis and arrhizus, respectively. The morphological type rouxii was polyphyletic in the clades of varieties arrhizus and delemar. Analyses about the population structure within R. arrhizus indicated that the variety delemar diverged first, then the variety tonkinensis and arrhizus, and finally subgroups of these three varieties each; these subgroups indicated that R. arrhizus is evolving molecularly along eight hybrid populations. For the first time, this study molecularly analyzed several R. arrhizus populations and deduced its evolution through genome-wide information, and confirmed that all ecological populations, taxonomic varieties, morphological types, biochemical groups and phylogenetic clades were conspecific, and no speciation occurrence.
Fruiting experiment of different mycelial growth stages of Hypsizygus marmoreus in bottled cultivation was carried out, and differential expression of pheromone pathway genes in different cultivation stages and key growth stages was investigated for revealing the role of pheromone signaling pathway genes in regulating the mycelial maturation, primordia formation and fruiting body development of the fungus. The results show that during 40-80 day mycelial cultivation, the fruit body production trends to upward tendency, indicating that the mycelium maturity has an important impact on the production. A total of eight key genes was obtained by analyzing and identifying the pheromone signaling pathway genes in the H. marmoreus genome. The differential expression analysis of pheromone pathway genes showed that during 40-80 day mycelial culture, most of the pheromone signaling pathway genes had the highest expression levels on the 60th day, of which ste20, cdc24, and ste12 were up-regulated 4-20 times, but decreased on the 80th day. In the process of mycelial regeneration, primordium formation and fruiting body development, most of the genes had the highest expression in the primordium stage and the expression decreased in the fruiting stage, of which the expression levels of ste20, cdc24, ste11 and ste12 were most significantly up-regulated. This indicated that the mycelial cells proliferated most vigorously on the 60th day, and began stagnancy on the 80th day, and then the mycelia gradually matured. During reproductive growth, the fungus continuously up-regulates the pheromone pathway gene expression to multiply the mycelial cells for primordium formation, in which the genes ste3, ste20, cdc24, ste11 and ste12 might play key role in proliferation of mycelia and the formation of fruiting bodies.
Sugarcane smut caused by Sporisorium scitamineum results in a great loss of yield as well as quality of sugarcane. The molecular mechanism of its pathogenesis remains largely elusive, hindering from the development of new method of disease control. Here, a concise method for gene knockout in Sporisorium scitamineum, based on the protoplast transformation with a pair of two PCR fragments was developed. Employing two key genes SsGPA3 and SsPRF1 as working model, the feasibility and efficiency of this method were evaluated. The results unraveled that when the haploid cells at exponential growth stage (OD600 about 0.7) were treated with 10mg/mL cell wall lyase for 30min at 28°C, a maximium of protoplast yield and the highest regeneration rate were achieved. Co-transformation of a pair of two linearized DNA fragments appeared more efficient than the transformation of one linearized DNA single fragment or plasimid. Successful establishment of this gene knockout strategy provides an important tool to investigate the gene function of Sporisorium scitamineum, and it could also be applied to knockout specific genes in other fungal pathogens.
Cordyceps militaris stroma on Antheraea pernyi contains a variety of active ingredients such as cordycepin, adenosine and polysaccharide having the effect of improving immunity, anti-fatigue, protecting cardio-cerebrovascular and anti-cancer. It is a good substitute for Cordyceps sinensis. Based on subculture of C. militaris on Antheraea pernyi, the growth state of fruiting body, the content of adenosine, cordycepin and polysaccharide in the stroma, and reactive oxygen species (ROS) in the mycelia and conidia were detected. The pupa of tussah decayed after infection of the first generation of C. militaris. The biomass of the fruiting body, and the content of adenosine, cordycepin, and polysaccharide in the stroma of the second and third generation of C. militaris obviously increased; 4th generation of C. militaris showed substantial decrease of fruiting body and the content of adenosine, cordycepin, and polysaccharide in the stroma. Cordyceps polysaccharide gradually decreased during successive subculture, but the decreasing range was slower than that of adenosine and cordycepin. The growth state of fruiting body of the second generation of C. militaris was better than that of the third generation. Therefore, the second generation is more suitable for batch production of C. militaris stroma. The increase of proportion of conidia containing reactive oxygen probably indicates deterioration of the fungus.
Lentinan is an important bioactive compound with high medicinal value. Methyl jasmonate contributes to increase the content of polysaccharide in edible fungi, but the knowedge about its effect on lentinan synthesis is still limited. In this study, using widely cultivated Lentinula edodes Xin-808 as tested strains, the impact of different concentrations of methyl jasmonate (MeJA) on the mycelial biomass and growth rate, the activity of key enzymes in the metabolism of polysaccharide, the relative expression of genes and the content of polysaccharide of L. edodes was analyzed. The results showed that 10μmol/L methyl jasmonate could significantly promote the mycelium growth and increase the mycelium biomass, respectively reaching 1.14 and 1.2 times higher than those of the experimental control (P<0.05). The activities of UDP-glucose pyrophosphorylase, glucose phosphate isomerase and α-phosphoglucomutase related to polysaccharide metabolism of L. edodes was respectively 1.58, 1.13 and 3.21 times higher than those of CK. The relative abundance of gene expressions was also significantly up-regulated, being 5.73, 1.40 and 1.77 times higher as compared with that of the CK, respectively. The quantity of lentinan also increased 1.58 times as compared with the control treatment. Under 10μmol/L MeJA treatment there was a positive correlation among the key enzymes’ activities, relative expression, and the polysaccharides’ content of L. edodes. In conclusion, appropriate concentration of MeJA would affect the growth of L. edodes mycelium and its crude polysaccharide synthesis.
The response surface method was used to optimize the preparation process of Cordyceps militaris mutant strain CSYB-2 mycelium polysaccharides. The results showed that the polysaccharide retention rate was (82.05±0.21)%, and the RSD of the process stability test was 2.53% under the conditions of chitosan dosage of 1.4mL/g, flocculation temperature of 55°C, and flocculation time of 70min. Mycelium polysaccharide extract of chitosan flocculant mutated strain CSYB-2 was used to construct a chitosan inactivation mechanical model, and the dynamics of flocculant during flocculation and the mechanism of inactivation were investigated. The test indicated that the inactivation mechanics of chitosan conformed to the inertia mechanics equation of the first-order reaction. The inactivation rate constant and activation energy are calculated based on the changes in the solution clarification rate (flocculation rate) at different times. This study provides theoretical support for investigating the mechanism of flocculant deactivation in flocculation.
This study aims at exploration of the chemical properties and protective effects on acute alcoholic liver injury of Trametes lactinea fruiting body polysaccharides (TLFPS). Polysaccharides were extracted by decoction and alcohol sedimentation, and their characteristics were analysed preliminarily by chemical composition determination, ultraviolet absorption spectrometry, fourier transform infrared spectroscopy and Congo red staining. The antioxidant activity in vitro of TLFPS was assessed by determination of ferric ion reducing antioxidant ability and scavenging free radical of DPPH, ABTS and superoxide anion. Polysaccharides were administrated to mice once daily for eight days before occurrence of alcoholic liver damage, and the protective effects of TLFPS against acute alcoholic liver injury in mice were evaluated by comparing related biochemical parameters and pathological section between experimental groups. Results showed TLFPS was β-pyran type polysaccharides without a triple helix structure, having high content of uronic acid and sulfate radical. In terms of antioxidant activity in vitro, the polysaccharides exhibited remarkable scavenging activities against DPPH radicals, ABTS radicals and superoxide anion radicals, and ferric ion reducing antioxidant ability was also notably stronger. In terms of liver protective activity, the polysaccharides had significantly prolonged the time of drunkenness, shortened the time of hangover and reduced the liver index, alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TC) in serum and malondialdehyde (MDA) in liver. Meanwhile, activity in liver of superoxide dismutase (SOD) and catalase (CAT) was increased. It was confirmed that TLFPS had higher antioxidative activity and obviously alleviate acute alcoholic liver injury without toxic effect on the body. The pathological section examination further confirmed the pharmacological activity of TLFPS. This study provided the pharmacodynamic basis for development of TLFPS in the field of functional food.
Sanghuangporus is currently recognized as one of valuable medicinal macrofungi with antitumor activity. The effects of harvest time on the content of active components (polysaccharide, total triterpenes, flavonoids and phenols) and antioxidant activity (ABTS and FRAP) of fruiting body were investigated on 30th, 45th, 60th, 75th, and 90th day after primordium formation of Sanghuangporus vaninii and S. baumii cultivated with sawdust medium. The result showed that harvest time significantly effected the content of polysaccharide, total triterpenes, flavonoids and phenols, and antioxidant activity (ABTS and FRAP) of the tested strains with the exception of the content of triterpenes of S. vaninii. The polysaccharide content of S. baumii increased sharp to the maximum on 75th day after primordium formation, and decreased slightly on 90th day, while that of S. vaninii maintained a high level on 45th, 60th and 70th day. The triterpene content of S. baumii reached the maximum value on 30th day, and then decreased slowly, while the triterpene content of S. vaninii had no significant change during whole harvest period. The total flavonoid and phenolic content, and antioxidant activities (ABTS and FRAP) of S. baumii and S. vaninii maintained a high level on 30th, 45th, and 60th day, and decreased sharp on 75th and 90th day. Correlation analysis showed positive correlation between the content of total flavonoid and phenols, and antioxidant activities of ABTS and FRAP. The polysaccharide content of S. baumii was significantly negatively correlated with the total flavonoid and phenolic content and ABTS and FRAP antioxidant activities, but not significantly correlated with the triterpenoid content. The polysaccharide content of S. vaninii has no significant correlation with the total flavonoid and phenolic content and antioxidant activities of ABTS and FRAP, but had a significant negative correlation with the triterpene content. The result of principal component analysis is consistent with that of cluster analysis, manifesting that the fruiting bodies formed on 30th, 45th and 60th day after primordium formation were grouped into one group, and the fruiting bodies formed on 75th and 90th day were grouped into another group. These results indicate that timely harvest is beneficial to the increase of active component content and antioxidant activity of Sanghuangporus fruiting body.
‘Chuanhougu 2’ is a new cultivar originated from a wild strain of edible Hericium erinaceus HT015 collected from Hailin of Heilongjiang Province. Its fruiting bodies are nearly elliptic, milky white, and the single body weight is 120-150g. The optimum growth temperature for mycelia is 18-22°C, and the optimum temperature for fruiting is 12-20°C. The growth period is 50-55 days, with 83% biological efficiency. It is suitable for cultivation in Liangshan Yi Autonomous Prefecture of Sichuan Province and other similar ecological areas.
The new Auricularia cornea cultivar ‘Haoyang Huangbei 1’ is suitable for factory cultivation using liquid and solid spawn for expanded reproduction. This cultivar originates from SH0072 strain introduced from Shanghai and breeds in Sichuan through tissue isolation, purification and systematic selection. The mature fruiting bodies are monolithically fascicular, with obvious stalks, ruffles, taupe colour and short fluffs on the upper surface. The suitable temperatures for mycelial growth and fruiting body development are 16-25°C and 15-32°C, respectively. The duration from primordium differentiation to the first fruiting body picking is 41-55 days, generally. The fruiting bodies can be harvested three times, with a converted efficency of 20.6%. This cultivar is resistant to infection of Scytalidium auricola. It is suitable for shed planting in Chengdu, Deyang, Jianyang cities and other similar ecological areas in Sichuan Province, and sack-culture on sterilized substrate in winter and harvesting in spring and summer.
A new cultivated strain of Pleurotus ostreatus, Zhuyan 1, was obtained by single-spore hybrid breeding. It is a medium-low temperature response variety with superimposed fruiting bodies and fan-shaped caps. Color is affected by temperature, and dark black at low temperature, dark gray at high temperature. The stalks are about 5cm long and 1.5cm in diameter, and the caps are 5-6cm in diameter and about 1cm thick when mature. The products are uniform and the pileus is thick and tough, with good commercial properties. Total amino acid content could reach 198.1g/kg and protein content 260g/kg. The production cycle is 45-50 days, and the biological efficiency is as high as 89.7%. The cultivar is suitable for cultivation in autumn and winter in Henan.
Pleurotus pulmonarius ‘Shenxiu 1’ was bred by single-spore inbred cross breeding technique using the ‘3108’ strain as the parent. Inter-simple sequence repeat (ISSR) identification shows that it has its own specificity as compared with the parent. After many years of cultivation, it is shown that ‘Shenxiu 1’ has high yield (average harvest of 505g per 500g dried substrate), good commercial properties (yielding above 90% of A-class commercial mushrooms), and short cultivation period (harvest period of 4-5 days after cold stimulation). Mycelium incubation stage showed stable, and primordia formed neatly after cold stimulation. The variety is distinctive for its strong stress resistance and other excellent characteristics, being able to meet the needs of high temperature off-season cultivation and temperature-controlled facility cultivation.
Paraffin section technique is used to observe the mycorrhizal anatomy features, invading ways and hyphal characters of mycorrhizal fungi in vegetative growth, flowering, fruiting and dormant periods of cultivated Bletilla striata, B. ochracea and B. formosana. The observation aims at understanding the relationship between mycorrhizal fungi and Bletilla plants and providing a reference for germplasm resources protection and sustainable utilization of the plants. The results showed that the mycorrhizal fungi invaded the parenchyma cells through passage cells, and the hyphae were distributed near the nuclei of cortical cells after invasion, and finally formed peloton in cortical cells. Hyphal infection and morphology changed with the growth and development of plants. Higher fungal infection rates occurred in flowering and vegetative growing periods, and the fungi appeared mainly in filamentous pelotons, but in fruiting and dormant periods mostly in clumpy pelotons with low infectivity. The mycorrhizal characteristics of different plant species in the same development period had no significant difference.
Endophytic fungi were isolated from the roots, shoots, leaves and fruits of Broussonetia papyrifera belonging to the Moraceae under harsh conditions in lead-zinc mine area. A total of 187 strains were identified, belonging to 20 genera, based on morphological and molecular biological methods. Alternaria (50.27%) and Fusarium (11.76%) were the dominant genera. The isolation rate of endophytic fungi varied with culture media, and potato glucose agar medium (PDA) produced the highest number of isolates, accounting for 73.96% of the total strains isolated. Most isolates were obtained from the leaves, accounting for 38.02% of the total strains. At genus level, the isolation rate varied with plant parts (roots, shoots, leaves and fruits). Shannon-Wiener index (H′) and Simpson index (D) indicated that the diversity of endophytic fungi varied with habitats of the plant. Chao1 index and ACE index also showed that the richness of endophytic fungi was related to the plant organs and habitats.
