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161.
Abstract

A Red List of all 108 Pezizomycotina (Ascomycota) species recorded in Umbria Region (central Italy) is provided. According to the IUCN categories and criteria, 60.18% of the assessed species are classified as threatened, whereas 12.96% are Near Threatened (NT), 1.86% are Least Concerned (LC) and a noteworthy amount of 25% are Data Deficient (DD). As a consequence of the downlisting applied to the majority of the assessed taxa, according to the guidelines for application of IUCN red list criteria at Regional level, only 1.54% of the threatened species is Critically Endangered (CR), while 46.15% are Endangered (EN) and 52.31% are Vulnerable (VU). Given that the present work represents the first complete regional red list of Pezizomycotina in Italy, and that a national, as well as a European red list do not exist to date, it could be considered as a case study for other Italian Regions as well as for other European countries, aiming at the compilation of a national and European red list of this fungal group mostly overlooked in conservation strategies.  相似文献   
162.
以不同灵芝品种、不同栽培基质、不同管理方式、不同生长时期获得的灵芝子实体为原料,用95%乙醇超声提取,对提取物进行了含量测定、三萜组成分析和体外抗肿瘤实验。结果表明,不同子实体醇提物中三萜和甾醇类物质的含量在4.60-6.20mg/g之间;高效液相分析发现10种三萜化合物的种类和含量在样品间存在明显差异。所有灵芝子实体醇提物对肿瘤细胞L1210的增殖均有一定的抑制作用,开伞期的灵芝子实体醇提物抑制肿瘤增殖的活性优于其他生长时期。  相似文献   
163.
杜蕊  戴玉成 《菌物学报》2020,39(4):637-644
本文报道了产自斯里兰卡的干皮孔菌属一个新种,该种的主要特征是具有平伏反卷或具菌盖的子实体,很小的孔口(每毫米8-10个),菌丝系统二系,生殖菌丝覆盖有刺状结晶,骨架菌丝橙棕色,细腊肠状担孢子(2.7-3.4×0.5-0.8μm)。基于ITS和nLSU序列的系统发育分析表明该新种属于干皮孔菌属的一个明确的分支。此外,将毛孔菌属组合到干皮孔菌属中,并报道了3个组合种,白边干皮孔菌、印度干皮孔菌和萨彦干皮孔菌。  相似文献   
164.
从一株特殊生境荒漠药用植物沙蓬的内生真菌Rhinocladiella similis中分离得到4个苯甲酸大环内酯化合物,包括2个新化合物rhinoclactones E(2)和F(1)、2个已知化合物8,9-dihyrogreensporone D(3)和8,9-dihydrogreensporone A(4)。基于高分辨质谱与核磁共振谱数据以及相关文献比对,确定了新化合物与已知化合物的结构。化合物1和2是一对立体异构体,在大环内酯环中并有一个呋喃环,这种环系统在自然界比较稀少。化合物1-4对3株肿瘤细胞株和植物病原真菌没有抑制活性。本结果进一步丰富了该真菌的化学成分研究,暗示特殊生境荒漠植物内生真菌具有产生结构新颖的次级代谢产物的潜力,是发现新活性天然产物的一个新的重要宝库;此外,根据化合物的结构特征与生物活性结果,本文还探讨了这些化合物潜在的生态学功能。  相似文献   
165.
166.
The genus Fusarium is noted for including important plant pathogens and mycotoxin producers. Furthermore, many Fusarium lineages have been reported to be efficient in controlling insects and to exhibit promising characteristics for agricultural pest control such as causing high mortality rates and having fast action and abundant sporulation. In this review we present a survey of peer-reviewed papers published from 2000 to 2019, demonstrating the widespread pathogenicity of Fusarium to insects. This survey was made using search strings in a number of databases. We list the major complexes and species of Fusarium reported as entomopathogenic and highlight the features of interest for insect control as well as the advantages and implications of this practice. Out of a total of forty papers, at least 30 species and 273 isolates of Fusarium were reported as pathogenic to at least one species of insect. Ten complexes of Fusarium species harbor entomopathogenic fungi, of which F. incarnatum-equiseti, F. fujikuroi, F. oxysporum and F. solani (= Neocosmospora solani) species complexes represented the most abundant number of entomopathogenic strains. The entomopathogenic interactions of these fungi have received greater attention in recent years, but much remains to be explored, especially regarding the specificity of these fungi for the host insect, the production of undesirable secondary metabolites, and side-effect and safety tests organisms not targets. Detailed investigations in this regard will be crucial if we are to fully exploit the potential of Fusarium for controlling insect pests.  相似文献   
167.
Recently, it has been indicated that systematics is of no value to the traditional Chinese medicinal studies and industry of macrofungi. As a fungal taxonomist, I use three genera of the most famous medicinal macrofungi, viz. Sanghuangporus, Ganoderma and Ophiocordyceps, as examples to rebut this opinion. Generally, the well-established systematics are helpful in using correct Latin names for fungal species in medicinal studies; furthermore, the resulting medicinal functions can be exactly matched to a particular species; finally, the particular species can be applied for permissions of utilization in traditional Chinese medicinal industry. Therefore, systematics is crucial for unlocking the potential of macrofungi as valuable resources to be developed in the traditional Chinese medicinal studies and industry, and should continue to be of interest to not just fungal taxonomists but also biochemists, pharmacists and businessmen.  相似文献   
168.
Mycotoxins are present in almost all feedstuffs used in animal nutrition but are often ignored in beef cattle systems, even though they can affect animal performance. The objective of this study was to evaluate the effects of mycotoxins and a mycotoxin adsorbent (ADS) on performance of Nellore cattle finished in a feedlot. One hundred Nellore cattle (430 ± 13 kg) were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments. The factors consisted of two diets with either natural contamination (NC) or exogenous contamination (EC) and the presence (1 g/kg of DM; ADS) or absence of a mycotoxin adsorbent. The NC and EC diets had the following contaminations, respectively: 0.00 and 10.0 µg/kg aflatoxins, 5114 and 5754 µg/kg fumonisins, 0.00 and 42.1 µg/kg trichothecenes B, 0.00 and 22.1 µg/kg trichothecenes A and 42.9 and 42.9 µg/kg fusaric acid. At the beginning of the experiment, all animals were weighed, and four randomly selected animals were slaughtered to evaluate the initial carcass weight. After 97 days of treatment, all animals were weighed and slaughtered. There was no interaction among factors for the DM intake (DMI; P = 0.92); however, there was a tendency for the EC diets to decrease the DMI by 650 g/day compared to animals fed NC diets (P = 0.09). There was a trend for interaction among factors (P = 0.08) for the average daily gain (ADG), where the greatest ADG was observed for cattle fed the NC diet (1.77 kg), and the lowest was observed for those fed the EC diet (1.51 kg). The NC + ADS and EC + ADS treatments presented intermediate values for ADG. The animals fed the NC diet had a greater final BW (596 kg) than animals fed the EC treatment (582 kg; P = 0.04). There was a tendency for interaction among factors for carcass gain (P = 0.08). Similarly to ADG, the highest carcass gain was observed for animals fed the NC diet (1.20 kg), and the lowest was observed for those fed the EC diet (1.05 kg). The NC + ADS and EC + ADS treatments presented intermediate values. The natural contamination groups had greater carcass gain than that of the EC groups, and the use of the ADS recovered part of the weight gain in animals fed the EC diet. In conclusion, mycotoxins at the levels evaluated affected the performance of beef cattle, and adsorbents may mitigate their impact.  相似文献   
169.
170.
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