This review summarizes the chemical constituents and bioactivities of the secondary metabolites from species of the genus Eutypella. Seventy-six natural products have been reported from the fungi including diterpenoids, cytochalasins, sesquiterpenoids, monoterpenoids, steroids and lactones. These chemical constituents exhibit various bioactivities such as anti-tumor, antibacterial action and immunosuppressive activity.
The taxonomy of Aspergillus subgenus Nidulantes has been changed greatly because of the proposal of “one fungus, one name” and nomenclature priority rules. The teleomorphic species belonging to Emericella were transferred to Aspergillus subgenus Nidulantes and some species concepts were updated. In this paper, we reviewed the taxonomic status, species concepts and secondary metabolites of subgenus Nidulantes. In addition, the strains cited in the Flora Fungorum Sinicorum Vol. 5 Aspergillus et teleomorphi cognati or deposited in CGMCC, being identified as Emericella species, isolated from 17 provinces and cities in China, were re-identified using calmodulin gene based phylogeny and morphological methods.
As an endogenous fungus of Zizania latifolia, Ustilago esculenta plays an important role in the formation of the swollen stem. In this study, 13 strains of U. esculenta (M-T type and T type) were isolated from different varieties and phenotypes of Z. latifolia. According to the ITS sequences and comparative analysis, all of the 13 strains was identified as U. esculenta. There were three bases′ variations in ITS1 sequence among different strains. Based on ISSR, genetic polymorphism analysis of the 13 strains was carried out. Cluster analysis showed that genetic polymorphism of U. esculenta strains are closely related to the cultivation characteristics and phenotypes of Z. latifolia. Genetic polymorphism of U. esculenta could provide complementary information in identifying and protecting germplasm resources of Z. latifolia.
Based on our sequenced genome of Puccinia striiformis f. sp. tritici and the published genomic proteins of Puccinia recondita f. sp. tritici and Puccinia graminis f. sp. tritici, using bioinformatics databases and analysis programs, the carbohydrate-active enzymes (CAZymes) of the wheat rust fungi were identified and the evolutionary mechanism of the CAZymes family was revealed. The result indicated that wheat rusts contained 1 232 CAZymes coding genes (including 1 279 modules), of which the stripe rust had larger CAZymes than the others, and these three wheat rust pathogens shared 136 homologous genes of CAZymes. In comparison with the leaf rust and stem rust, the GH, GT and AA families were significantly expanded in the stripe rust. There was no difference in PL family between them, but the CBM family displayed increasingly expanded from stem rust, leaf rust to stripe rust. Comparative analysis of annotations about CAZymes, cell wall degradation enzyme, secretory protein, PHI and conserved motif indicated that the stripe rust mostly preferred to expansion, and the leaf rust and stem rust showed different contraction levels. CAZymes family of the wheat rusts presents expansion or contraction in different forms that may reflect the parasitic adaptation and coevolution process of the wheat rusts and the host. The results of this study will benefit the understanding of the evolution of CAZymes families in wheat rusts, and future investigation of CAZymes in rust pathogenesis processes.
Phytophthora blight of capsicum caused by P. capsici is a worldwide disease in vegetable production, and its serious occurrence causes great economic losses. P. capsici secretes plenty of effectors to promote the infection and colonization while the host plant is infected. RxLR effectors play an important role in infecting the host and interaction between P. capsici and plants. In this research, P. capsici LT1534 is used as a model to clone an effector named RxLR121504 and the effector is fused to plant expression vector PBIN-GFP2. The function of RxLR121504 was investigated by using the techniques of Agrobacterium-mediated transient expression, Western blot and subcellular localization. The results show that RxLR121504 could efficiently induce hypersensitive response (HR) in Nicotiana benthamiana, and suppress cell death induced by elicitor INF1. Thus, RxLR121504 may participate in the process of pathogen-host interaction. However, the molecular target of RxLR121504 to host plant remains to be identified and its molecular mechanism is required to further study out.
Laccase is a type of multi-copper-containing polyphenol oxidases capable of oxidizing a wide range of substrate, and has important values in fields of food, energy, environmental protection and so on. Therefore screening of high-yield laccase producing strains is important for industrial applications. The present work was carried out to screen high-yield laccase producing strains from Lentinula edodes. PDA plates with guaiacol was used to preliminarily screen laccase producing strains from 78 L. edodes isolates according to growing characteristic of colony, and further screening was carried out by submerged fermentation. The specific or differential expression profiles of laccases in two different strains were analyzed by real-time quantitative PCR (qRT-PCR). The results showed that changes of oxidized and hyphal zones varied among strains. Ninteen strains were selected based on the sizes of oxidized and hyphal zones. Further screening showed that three strains, Xiang 240, 15 and Mianningqianhui, displayed highest level of laccase activity at 3.583U/mL (on the 3rd day), 3.842U/mL (on the 7th day) and 2.806U/mL (on the 7th day), respectively. The results of qRT-PCR showed that differential and specific expression profiles of ten L. edodes laccase genes were observed in two strains, of which two genes were specifically expressed in Xiang 240, and four genes (Lelac1-4) displayed higher expression levels in strain 15, while three genes (Lelac8, Lelac10 and Lelac11) were higher in Xiang240. These results provide fundamental data for further study of laccase from L. edodes.
Trichoderma species were commonly used as microbial biocontrol agents in agriculture due to their antagonism against plant pathogenic fungi. In order to increase screening efficiency at the first step, antagonistic ability of Trichoderma strains was investigated by dual culture method. As the results, different degrees of antagonism were recognized, i.e. strong, moderate, weak, and absent. Trichoderma strains having strong antagonism usually grow much faster than plant pathogenic fungi, produce rich hyphal coilings surrounding hyphae of plant pathogenic fungi, and sporulate on pathogenic fungal colony in 12 days. The strains having moderate antagonism grow slightly faster than or the same as plant pathogens, form hyphal coilings fairly well, and sporulate poorly in 30 days; alternatively, hyphae coilings are less commonly seen or nearly absent, and sporulation occurred in 12 days. Those with weak antagonism grow more or less at the same speed with the plant pathogenic fungi, produce relatively poor hyphal coilings, and sporulate poorly or even none in 30 days. The Trichoderma strains lack of antagonistic ability grow slowly, and their colonies are very restricted and even overgrown by that of the plant pathogens. In this evaluation method, both competition and mycoparasitism were taken into consideration. It is suitable to evaluate antagonistic potential of Trichoderma strains in vitro at first step.
The ecological pattern dominated by microbiotic crust in the Shapotou area of the Tengger Desert is one of the unique ecological landscapes in natural vegetation of desert areas. Lichen, an important component of microbiotic crusts, plays a crucial role in influencing ecological changes. In this study, we investigated species composition and coverage of vascular plants and lichens, measured concentration of major nutrients in crust soil. The results show that the dominant lichens in microbiotic crusts are taxa of Collema and Endocarpon. We also observed roughly significant positive correlations between vascular plants and microbiotic crust converges, thickness of crust and concentration in soil nutrients, all which posing an increasing trend with ages of artificial vegetation. The consistent patterns of parameters of vascular plants, microbiotic crusts, lichens and soil nutrients clearly suggest a positive effect of microbiotic crusts on shallow-rooted vegetation and soil restoration, and provide a necessary theoretical basis for the artificial sand control and the full implementation of the desert bio-carpet engineering.
The crude polysaccharide named as HZKJc was extracted from Lenzites betulina by water extraction and alcohol precipitation, and then deproteinized by Enzyme-Sevage combined method. The crude polysaccharide was purified by DEAE-Sephadex A-25 and G-100 gel filtration chromatography to obtain pure polysaccharide products HZKJv. The purity and relative molecular weight distribution of HZKJv were determined by high performance liquid chromatography (HPLC). Monosaccharide composition was analyzed by paper chromatography (PC), gas chromatography (GC) and infrared spectroscopy (IR). The free radical scavenging activities of purified polysaccharide were investigated. HZKJv was a homogeneous polysaccharide with average molecular weight of 11 687. When the concentration of HZKJv was 3.0mg/mL and 2.0mg/mL, the ·OH and DPPH free radical scavenging rate can be up to 82% and 85%, respectively, indicating that HZKJv had excellent scavenging effect on ·OH and DPPH free radicals.
The anti-tumor activity of different extract including petroleum ether extract, methylene chloride extract, ethyl acetate extract, methanol extract and water extract of Funalia trogii fruiting body was investigated by establishing tumor bearing mice model. The inhibition ratio, body weight, thymus index, spleen index, and liver index, kidney index in H22 tumor bearing mice were analyzed; the histopathologic changes of tumor, spleen and kidney were observed and the content of IL-3, IL-4, IFN-γ and TNF-α in blood serum of the H22 tumor bearing mice were detected. The results showed that all the extract showed obvious anti-tumor activity. The anti-tumor activity of moderate dose (1 000my/kg) of ethyl acetate extract was the best and significantly different (P<0.01) as compared with the control, and the content of IL-2 in the serum of H22 tumor bearing mice was increased significantly. The tumor cells were observed by HE staining. The necrosis area was found in the tumor of experimental mice treated by ethyl acetate extract, confirming the anti-tumor activity of the extract.
The anti-tumor activity and mechanism of Auricularia cornea fruiting body extract in H22 bearing mice was studied by detecting the tumor-inhibition rate, spleen and thymus index, content of IL-2, TNF-α, IFN-γ, MDA, SOD, CAT and GSH-Pxin serum and observing pathological section of tumor of H22 mice. The result was that the tumor-inhibition rate of H22 mice treated with high dose and low dose of ethyl acetate extract was 39.9% and 37.5% respectively; the necrosis was found in the tumor of the all treating groups, and the necrosis area in high dose treating group of ethyl acetate extract was obviously larger than that in low dose treating group through observing the tumor section stained with HE. Compared with model group, ethyl acetate extract could enhance immune activity and increase the content of IL-2, TNF-α, IFN-γ significantly. It is proved that Auricularia cornea fruiting body extract has potential anti-tumor effect.
The basidiomycete genus Galerina (Basidomycota, Agaricomycetes, Agaricales, Strophariaceae) accommodates more than 300 species worldwide, predominantly described from the northern hemisphere, and more than 30 species were found in China, of which more than 20 species have been confirmed; this paper is a supplement to previous work. Three species of the genus Galerina, namely G. pumila, G. atkinsoniana and G. stylifera were reported from China for the first time. The morphological descriptions are given in detail. The line drawings of the macrostructures of basidiomata and microstructures of basidiospores, basidia, cheilocystidia, caulocystidia and pileipellis are provided. SEM images of the ornaments on the surface of basidiospores are given. ITS sequences obtained by the authors and some sequences obtained from EMBL/GenBank are analyzed to affirm the reseults of previous morphological identifications. GenBank sequences of Gymnopilus junonius and Gymnopilus sapineus are used as outgroup in the analyses of ITS. Bayesian phylogenetic tree strongly affirmed the identity of morphological identification of the three Galerina species.
