Ganoderma triterpenoids are major pharmacologically active components in the fruiting bodies and mycelia of G. lingzhi. Structure-activity relationship, basic biosynthetic pathways and key enzymes, as well as strategies and methods for the fermentation control of triterpenoids from G. lingzhi were reviewed. The main problems in biosynthesis and fermentation control of triterpenoids were put forward and the future research orientation and prospect were discussed.
A new species, Passalora puerariigena, causing angular leaf spot of lobed kudzuvine (Pueraria lobata), is reported from China. Latin diagnosis, Chinese description, illustration and discussion are provided. Type specimen is deposited in HMAS.
Glomerella leaf spot pathogens can infect apple leaves and fruit, causing extensive necrosis of leaves and premature defoliation, as well as necrotic spots on fruit. In recent years, the disease has been reported with increasing frequencies in China, and appears to be spreading rapidly in some apple-producing areas. In this study, fungal isolates from diseased apple leaves collected in Henan and Shaanxi provinces were identified based on morphology, cultural characters, pathogenicity and molecular phylogenetics. It was found that Glomerella leaf spot of apple was caused by two pathogens, Colletotrichum fructicola and C. aenigma. Pathogenicity tests showed that C. fructicola and C. aenigma could infect apple leaves of cultivar Golden Delicious and its parentage varieties such as Gala, Qinguan, Pink Lady, Pacific Rose, Jinshiji and Honeycrisp. In wound inoculation experiments, C. fructicola and C. aenigma were pathogenic to fruit of Gala, Qinguan, Golden Delicious, Pacific Rose, Starkrimson and Fuji. Non-wounded inoculation of fruit indicated that C. fructicola was pathogenic to Gala and Golden Delicious, and C. aenigma was pathogenic to Gala. It is concluded that the pathogenicity differentiation is present for the pathogens on leaves and fruit of different apple cultivars.
For the study of Floccularia luteovirens population genetic structure, ITS and LSU sequences of 91 samples of Floccularia luteovirens belonging to 10 geographic group from Qinghai, Tibet and Sichuan were analyzed. Eight variable sites existed among the aligned sequences of 1 995bp, and 20 genotypes were found. The average haplotype diversity (Hd) was 0.538±0.026, while the nucleotide diversity (pi) was 0.00029±0.00002. Analysis results of molecular variance showed that the majority of genetic variation of the Floccularia luteovirens groups occurred within populations (75.70%), and the genetic difference among populations was greater. Phylogenetic tree also showed that 10 populations of Floccularia luteovirens were divided into two branches, illustrating that Floccularia luteovirens had obvious geographical structure. The neutrality test results further confirmed that the Floccularia luteovirens groups had relatively complicated demographic history, undergoing a long process from population expansion to recent populations decline.
In order to detect the genetic diversity, population genetic structure and intraspecific differentiation of Isaria farinosa, the ITS sequencing and RAPD amplification were conducted in 8 local populations of Isaria farinosa and 2 local populations of Paecilomyces hepiali in Yunnan. Together with the ITS sequences in GenBank, a total of 97 ITS sequences of I. farinosa were obtained in the 6 populations from widely separated geographical locations. The 33 haplotypes were discovered in the populations sampled of I. farinosa. The haplotype (gene) diversity was Hd=0.546 and nucleotide diversity was Pi=0.00276, showing lower degree of genetic diversity at the species level. A total of 14 haplotypes were found in the local populations of Yunnan, and 10 of them were not found elsewhere. The haplotypes’ clustering and network analyses demonstrated a richer genetic diversity of I. farinosa in Yunnan. The coefficient of genetic differentiation from ITS sequence analysis was Fst=51.95% among the 8 local populations in Yunnan. The gene flow from RAPD analysis was Nm=0.4014. It was shown that a great genetic differentiation was presented in the local populations of I. farinosa in Yunnan. The results of mantel tests revealed that there were no significant correlations between the average genetic distance and the geographic distance among geographically distant or local populations. Neutrality test and mismatch analysis revealed that the species went through a recent population expansion. By combining the results from haplotypes clustering and network analysis, it was inferred that the haplotype (Hap 19) might be the founder. However, the original ancestor haplotype (Hap 1) also had absolute predominance. These results indicated that I. farinosa did not experience an obvious reproductive isolation. In addition, P. hepiali could be considered the synonym of I. farinosa based on ITS haplotypes and RPAD analyses.
Isolation and identification of seawater samples collected in Zhanjiang Bay, Guangdong Province, China in January 1, 2010 have yielded a variety of marine fungi. The most dominant genus was Cladosporium, in which C. sphaerospermum, C. cladosporioides, C. colocasiae, C. tenuissimum, C. oxysporum, C. perangustum, and C. uredinicola were common; Penicillium, including P. verruculosum, P. griseofulvum, P. sclerotiorum, P. pinophilum, P. aculeatum, and P. simplicissimum, was of the second dominance. Engyodontium with a single species, E. album, ranked third, while Aspergillus, including A. terreus, A. aculeatus, A. flavus, and A. fumigatus, came fourth. As for dominant rate, the dominant species were C. sphaerospermum (7.97%), E. album (3.60%), C. cladosporioides (3.29%), and P. verruculosum (3.04%). C. perangustum was a newly recorded species in China. In all 19 sampling sites, the fungal population in the sea surface showed significant positive correlation to PO43--P or SiO32--Si. There was also significant positive correlation between population of Engyodontium and Aspergillus and total organic carbon (TOC). Significant negative correlation was showed between the population of Aspergillus and Engyodontium and pH, and between Aspergillus population and salinity. It showed significant positive correlation between the population of sea bottom fungi and TOC and suspended substance. Significant positive correlation was evident between population of Cladosporium and suspended substance, between population of Engyodontium and dissolved oxygen and TOC, and between population of Aspergillus and TOC. Significant negative correlation was present between the population of sea bottom fungi and pH. The correlation was not significant between the population of fungi and water temperature, sea depth, or greasy dirt.
Root-rot is a common disease in plantation of Panax notoginseng, which is more or less affected by community structure and function of rhizosphere soil fungi. In the present study, rhizosphere soil samples were collected in healthy and diseased fields of P. notoginseng in Wenshan of Yunnan Province for analysis of community composition of soil fungi by terminal restriction fragment length polymorphism (T-RFLP) and utilization of carbon sources by Biolog FF microplate. The results indicated that the diversity and metabolic activity of rhizosphere soil fungi had no significant difference between the rhizosphere soil of healthy and diseased plants, but their fungal community compositions were different. The most abundant fungi in rhizosphere soil of both healthy and diseased plants included Phoma exigua and Fusarium spp. However, the isolation rates of Pyronema spp. and Mortierella spp. were much higher in the rhizosphere soil of healthy plants than that of diseased plants. On the contrary, the isolation rates of F. oxysporum and Volutella colletotrichoides in the rhizosphere soil of healthy plants were obviously lower than in that of diseased plants.
The sporulating conditions and sporulation capacity of Colletotrichum orbiculare were investigated by adjusting nutrients, physical and chemical properties of culture media and culture conditions. It was found that the pathogen plentifully produced conidia on watermelon stem-leaf-decocting juice medium at 25°C for 30d in dark condition and the spore concentration reached 7.15×109 spores/mL. Microscope observation showed that the conidia produced on watermelon stem-leaf-decocting juice medium and those produced on watermelon stem lesions were different. The conidia produced on watermelon stem-leaf-decocting juice medium were slightly wider and shorter and obtuse on both ends, while those produced on watermelon stem lesions relatively longer and thinner, and more pointed at both ends. The nutrients of the host plant in the medium could promote the conidial production of the fungus.
In order to understand the role of arbuscular mycorrhizal (AM) fungi in the invasion process of Flaveria bidentis, a harmful introduced plant species, and the characteristics of AM on the plant grown in Xiaobeitian village of New Binhu region, Zhangxia village of Jizhou city, Beiwangzhuang village of Zaoqiang county, Balizhuang village of Taocheng district, Liujiatai village of New Binhu region and Shunminzhuang village of New Binhu region were investigated. Sample sites with heavy, medium and light coverage of Flaveria bidentis being in seedling, flowering and seed-bearing stage period were selected and soil with root samples were collected to isolating AM fungal spores, observing the characteristics of AM, and determinating spore density and arbuscular mycorrhizal colonization. The results showed that the typical structure of AM in different regions was evident. The maximum level of hyphal colonization, intermediate-arbuscular density and spore density appeared in Balizhuang village, and the maximum level of vesicle density and Arum-type arbuscular density respectively appeared in Xiaobeitian village and Liujiatai village. The maximum level of AM colonization all appeared in heavy invasive plots under different cover degree of the plant. The maximum level of arbuscular density appeared in flowering stage, and the maximum level of hyphal colonization, vesicle density and spore density appeared in seeding period. Hyphal colonization was not significantly different in different growth stages. Soil properties also significantly affected mycorrhizal development. There were positive correlation between hyphal colonization and organic matter, but hyphal colonization was negatively correlative with pH value and significantly negatively correlative with available P. There were negative correlation between Arum-type arbuscular density and pH value. A significantly positive correlation existed between intermediate-arbuscular density and total nitrogen, and significantly positive correlation existed between spore density and total nitrogen and organic matter content. It was concluded that AM colonization would improve the invasion of the plant. The results might provide possible pathways to control this invasive alien plants.
The full length of stf1 gene of Eurotium cristatum has been cloned by RACE technology. It has total length of 3 029bp including an open reading frame (ORF) of 2 664bp interrupted by one 131bp intron. The gene encodes a predicted protein of 887 amino acids that shares very high sequence identity with a Snd1/p100 transcription factor. The expression of stf1 gene in different development phases was determined by SYBR Green I real time PCR analysis. The result revealed that the expression of stf1 gene was reduced by almost one-fold in asexual sporulation as compared with sexual sporulation. These works are useful for studying the sporulation regulatory mechanism of E. cristatum.
Pre-mRNA splicing plays an important role in regulating eukaryotic gene expression, which is mediated by the spliceosome complex. snRNAs are crucial components for the structure and function of spliceosome. In this work, we identified the snRNA genes from Neurospora crassa, which included U1, U2, U4, U5 and U6, and each comprised various variant numbers with the exception of U5. These snRNA gene variants show different expression levels. Analysis of the proximal sequence elements indicated that a palindromic consensus sequence GTGCAC existed in most of these snRNA genes. The regulation of some snRNA genes transcribed by this sequence was confirmed via luciferase assay. We further examined the stk-16’s intron-3 alternative splicing in temperature gradient, and the results suggest that alternative splicing may have a role in climate temperature change adaptation.
The phyletic evolution and conserved domain of amino acid sequence of grey mold Botrytis cinerea, MAT1-1-1 and MAT1-2-1 were analyzed. The results showed that the genetic relationship of B. cinerea mating type protein MAT1-1-1 and MAT1-2-1 was close to that of Sclerotinia sclerotiorum. The amino acid sequence alignment of mating type protein domains showed that the genes had conserved amino acid identity and partial amino acid similarity. The mating type genes, MAT1-1-1 and MAT1-2-1, were detected by PCR technique and the results showed that the mating type distribution ratio of the strains in different fields had great difference. In most planting regions both mating types were detected. Quick detection of mating type genes from grey mold isolates is very important for the analysis of population structures based on mating type patterns.
Seven compounds were isolated from the extract of the marine fungal strain Penicillium sclerotiorum FS50 fermented on rice by various chromatographic methods such as sillica gel, reverse silica gel, Sephadex LH-20, preparative TLC and HPLC. Their structures were determined as butyl 6,8-dihydroxy-1-oxo-1H-isochromene-3-carboxylate (1), 6,8-dihydroxyisocoumarin-3-carboxylic acid (2), 3-carboxy-8-hydroxy-6-methoxy-1-oxo-1H-2-benzopyran (3), (+)-sclerotiorin (4), 4-methyl-5,6-dihydropyren-2-one (5), 5-hydroxymethylfurfural (6), daucosterol (7) by extensive analysis of the spectroscopic data. Compound 1 was identified as a new compound, and compounds 2, 3 and 6 were isolated for the first time from Penicillium.
Six compounds were isolated from fruiting bodies of Phellinus baumii by using column chromatography. According the spectral data, they were identified as ergosta-7,22-dien-3β-yl pentadecanoate (1), ergosta-7,22-dien-3β-ol (2), ganoderiol B (3), ergosta-6,2-dien-3β,5α,8α-triol (4), ganoderic acid DM (5), and inoscavin A (6). By in vitro cytotoxicity screening, compounds 1, 2, 4, 5 and 6 were found to inhibit the proliferation of K562 tumor cells with IC50 of 63.5, 10.3, 70.6, 35.9 and 3.5μg/mL respectively. Compound 5 showed strong inhibition to the proliferations of HepG2 with IC50 of 50.3μg/mL.
By using key stage-speed control strategy, the two-stage culture process of Ganoderma lingzhi was optimized in order to obtain hyper-production of total GA content. The process of variable speed from 150r/min to 100r/min, as the optimal condition in oscillation culture phase, was combined with liquid static culture. In process of the novel two-stage culture, the total Ganoderic acids production (GA) of G. lingzhi was improved to 678.0g/L which was 21% higher than the control. It is effective to improve total GA production by using stage-speed control strategy in oscillation culture stage.
The extraction technology and anti-microbial activities of schizophyllan polysaccharose were studied by enzymatic technology. The effects of pH, enzymolysis duration, enzymolysis temperature and additive amount of enzyme on schizophyllan extraction rate were investigated. Based on single factor experiments, response surface methodology was used to optimize the process parameters. Results showed that under the conditions of liquid pectinase’s pH value of 5.5, enzymolysis duration of 1.2h, enzymolysis temperature of 50°C and enzyme additive amount of 1%, the schizophyllan polysaccharose extraction rate was 54.76%. Schizophyllan had inhibiting effect to Escherichia coli and Pseudomonas sp. proliferation.
Three species of Aspergillus namely A. dimorphicus, A. fumigatiaffinis and A. westerdijkiae were newly recorded in China. The morphological characteristics and β-tubulin gene difference were compared with allied species. The ochratoxin A (OTA) producing ability was analyzed by using liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). Aspergillus westerdijkiae CGMCC3.15268 could produce OTA at the level of 17.26µg/kg on rice medium, while A. fumigatiaffinis CGMCC3.15275 and A. dimorphicus CGMCC3.17045 were OTA negative.
Tobacco powdery mildew was found in greenhouses and laboratories in Qingdao. Based on morphological characteristics, rDNA-ITS sequence analysis and pathogenicity test, the pathogen was identified as Golovinomyces orontii. To our knowledge, this is the first report of Golovinomyces orontii causing tobacco powdery mildew in China.
The culturable endophytic fungal communities and diversities were investigated from 25 healthy fruits of Ziziphus jujuba ‘Huizao’. Seventy-two fungal strains belonging to 12 species of 7 genera were isolated and identified. Diaporthe infecunda was a new record in China. Bipolaris and Pseudocercospora were firstly reported on fruits of Zizyphus jujuba.
The powder of Ramalina conduplicans thallus were extracted by petroleum ether (30-60), dichloromethane and ethyl acetate. Six compounds were isolated and identified, they were usnic acid (1), atranorin (2), barbatic acid (3), evernic acid (4), diffractaic acid (5) and salazinic acid (6). They were all for the first time found from Ramalina conduplicans. The antioxidant activity of the six compounds were assessed based on the ability to scavenge DPPH and ABTS free radicals in vitro. The result showed that there was a dosage-dependent effect between DPPH·removal effect and mass concentration of salazinic acid in the test concentration range. In 55µmol/L, the clearance rate of salazinic acid is 57.05%. In 13.75-55µmol/L, there was a dosage-dependent effect between DPPH·removal effect and mass concentration of atranorin, barbatic acid and evernic acid. DPPH·removal ability of usnic acid is better. There was a dosage-dependent effect between ABTS·+ radical scavenging effect and mass concentration of diffractaic acid, salazinic acid and barbatic acid. When the concentration is 55µmol/L, ABTS·+ free radical clearance rate of diffractaic acid is 50.79%, that of salazinic acid is 44.53%, and that of barbatic acid is 44.34%. In 13.75-55µmol/L, there was a dosage-dependent effect between ABTS·+ free radical clearance rate and mass concentration of atranorin. There are benzofuranone, depsides and its derivatives in Ramalina conduplicans, so the lichen can be developed an important source of potential antioxidants.
