茶藨子叶孔菌子实体(忍冬)的化学成分研究(英文)

从茶藨子叶孔菌(忍冬)中分离了8个化合物,通过波谱法和理化性质分别鉴定为豆甾醇(1),二十八酸(2),β-谷甾醇(3),麦角甾醇(4),麦角甾醇过氧化物(5),壬二酸(6),烟酸(7),原儿茶酸(8)。化合物1,3,6均为首次从该属真菌中分到。     

西澳粘滑菇的化学成分研究

利用各种常规色谱分离技术从西澳粘滑菇(Hebeloma westraliense)发酵液中分离得到5个化合物,经波谱学分析鉴定为Volemolide(1)、过氧化麦角甾醇(2)、对羟基苯甲酸(3),对甲氧基苯乙酸(4)和对羟基苯乙醇(5)。其中化合物1是一个七降麦角甾醇类物质,系首次从丝膜菌科真菌中分离得到。     

棱柄马鞍菌子实体的化学成分研究

采用多种色谱方法和现代光谱技术对棱柄马鞍菌Helvella lacunosa子实体的化学成分进行分离纯化,得到11个化合物,并进行了结构鉴定,分别是麦角甾-5,22-二烯-3β-醇(1)、麦角甾醇-3-O-β-D-葡萄糖苷(2)、麦角甾醇(3)、麦角甾醇过氧化物(4)、苯甲酸(5)、3,7-二甲基-正辛基3α醇-1-苯甲酸酯(6)、腺嘌呤核苷酸(7)、尿嘧啶(8)、甘露醇(9)、Withaferin A(10)、邻苯二甲酸二丁酯(11)。所有化合物均为首次从棱柄马鞍菌子实体中分离得到。     

苦竹内生真菌Phomopsis sp.KY-12化学成份及其海虾致死活性研究

利用柱色谱技术从苦竹内生真菌中分离得到13个化合物,包括九个杜松烷型倍半萜、一个azaphilone类化合物和三个甾体类化合物,经波谱鉴定为为3,12-dihydroxycalamenene(1),3,9,12-trihydroxycalamenene(2),indicumolide C(3),agripilol C(4),2,15-tihydroxycalamenene(5),dysodensiol D(6),bombamalones D(7),8-formyl-7-hydroxyl-5-isopropyl-2-methoxy-1,4-naphthoquinone(8),strobilol A(9),Pyrenocine J(10),3β,5α-Dihydroxy-6β-methoxyergosta-7,22-dien(11),麦角甾醇(12)和麦角甾醇过氧化物(13)。其中,化合物3-9为首次从该属真菌中分离得到。化合物1~8显示中等程度的细胞毒活性,化合物9显示显著的细胞毒活性。     

苦荞麦麸皮的化学成分研究

从苦荞麦麸皮浸膏中分离得到7个化合物,经波谱分析确定结构分别为：β—谷甾醇(1)、过氧化麦角甾醇(2)、大黄素(3)、胡萝卜甙(4)、山奈酚(5)、异山奈酚(6)和槲皮素(7)。化合物1—6为首次从苦荞麦麸皮中分离得到。     

人参内生球毛壳菌株RSQMK-9的化学成分研究北大核心CSCD

从人参内生球毛壳菌株RSQMK-9的发酵培养物中提取分离得到14个代谢产物,通过波谱分析鉴定其结构分别为麦角甾醇(1)、4,6,8,22-四烯-3-酮-麦角甾烷(2)、啤酒甾醇(3)、9(11)-去氢麦角甾醇过氧化物(4)、alternariol(5)、大黄素甲醚(6)、3-吲哚甲酸(7)、2,3,4-三甲基-5,7-二羟基-2,3-二氢苯并呋喃(8)、2-氨基苯甲酰胺(9)、2-氨基苯甲酸(10)、3-甲基苔色酸(11)、甘露醇(12)、chaetoglobosin A(13)及5'-epichaetovirdin A(14)。这些化合物均为首次从人参内生球毛壳菌中发现,而且化合物6为首次从该属真菌中分离到。海虾致死试验结果显示:10μg/mL浓度下,化合物13和14对丰年虾的致死率分别为83.4%和54.3%。     

蝙蝠蛾拟青霉菌丝体化学成分的研究

应用梯度提取、反复重结晶及硅胶色谱法分离和纯化,采用NMR等谱学方法鉴定结构对蝙蝠蛾拟青霉(Paecilomyces hepiali)菌丝体进行了化学成分的分析。从蝙蝠蛾拟青霉菌丝体中分离得到6个化合物,分别鉴定为4,6,8(14),22(23)-四烯-3-酮-麦角甾烷(1)、麦角甾醇(2)、β-谷甾醇(3)、麦角甾醇过氧化物(4)、啤酒甾醇(5)、甘露醇(6)和1-油酰基-2-亚油酸-3-棕榈酸甘油(7),并对其石油醚提取物中的油状组分进行GC-MS分析,结果表明其中主要为亚油酸(9,12-十八碳二烯酸,含量41.949%)、反油酸(反9-十八碳烯酸,含量为27.696%);同时采用高效液相色谱法测定其中的麦角甾醇的含量,与海鲜菇、杏鲍菇、香菇、金针菇、滑子蘑、平菇等食用菌子实体比较,结果蝙蝠蛾拟青霉菌丝体中麦角甾醇含量为15.65 mg/g,平菇为21.43 mg/g,杏鲍菇为10.16 mg/g,香菇为13.34 mg/g,金针菇为9.48 mg/g,滑子蘑为10.43 mg/g,海鲜菇为14.42 mg/g。     

植物内生真菌Fusarium guttiforme次生代谢产物研究CSCD

采用多种色谱分离方法从植物内生真菌Fusarium guttiforme次生代谢产物中分离纯化得到7种化合物,并通过核磁共振和质谱等波谱学手段鉴定其结构,包括一个新型含过氧键的二聚苯衍生物:fucinum A(1)以及6个已知化合物:(Z)-1-hydroxy-4-(2-nitroethenyl)benzene(2)、对羟基苯甲醛(3)、stigmasta-4,6,8(14)-trien-3-one(4)、stigmast-4-ene-3,6-dione(5)、麦角甾醇(6)、5-羟甲基糠醛(7)均首次从该真菌次生代谢产物中分离。此外,对上述化合物进行NO生成抑制活性实验的研究,其结果表明化合物1、2对NO产生具有一定的抑制作用,IC_(50)值分别为48.1和46.6μmol/L。     

地衣内生菌Myxotrichum sp.的代谢产物的研究

采用硅胶柱色谱,重结晶,高效液相色谱等分离方法从地衣内生菌Myxotrichum sp.的发酵液中共分离得到10个化合物,根据理化性质和波谱数据分别鉴定为:麦角甾醇(1),(3β,5α,8α,22E,24R)-5,8-epidioxy-ergosta-6,9(11),22-trien-3-ol(2),麦角甾醇过氧化物(3),7-羟基-2,5-二甲基色原酮(4),7,8-dihydro-7,8-dihy droxy-3,7-dimethyl-2-benzopyran-6-one(5),7-hydroxy-2-(2-hydroxypropyl)-5-methylchromone(6),Anhydroful vic acid(7),柠檬霉素(8),2,3二羟柠檬菌素(9),柠檬菌素(10)。化合物4~10的体外抑制人白血病细胞K562实验表明,该七种化合物均表现非常弱的细胞毒活性。     

人参内生球毛壳菌株RSQMK-9的化学成分研究

从人参内生球毛壳菌株RSQMK-9的发酵培养物中提取分离得到14个代谢产物,通过波谱分析鉴定其结构分别为麦角甾醇(1)、4,6,8,22-四烯-3-酮-麦角甾烷(2)、啤酒甾醇(3)、9(11)-去氢麦角甾醇过氧化物(4)、alternariol(5)、大黄素甲醚(6)、3-吲哚甲酸(7)、2,3,4-三甲基-5,7-二羟基-2,3-二氢苯并呋喃(8)、2-氨基苯甲酰胺(9)、2-氨基苯甲酸(10)、3-甲基苔色酸(11)、甘露醇(12)、chaetoglobosin A(13)及5'-epichaetovirdin A(14)。这些化合物均为首次从人参内生球毛壳菌中发现,而且化合物6为首次从该属真菌中分离到。海虾致死试验结果显示:10μg/mL浓度下,化合物13和14对丰年虾的致死率分别为83.4%和54.3%。     

A novel sterol from Chinese truffles Tuber indicum

From the fruiting bodies of Ascomycetes Tuber indicum, a new steroidal glucoside with polyhydroxy ergosterol nucleus, tuberoside (2), has been isolated along with additional four known ergosterol derivatives, (22E, 24R)-ergosta-7, 22-dien-3beta, 5alpha, 6beta-triol (1), 5alpha, 8alpha-epidioxy-(22E, 24R)-ergosta-6, 22-dien-3beta-ol (3), (22E, 24R)-ergosta-5, 22-dien-3beta-ol (4), and (22E, 24R)-ergosta-4, 6, 8(14), 22-tetraen-3-one (5). The structure of new compound was established as 3-O-beta-D-glucopyranosyl-(22E, 24R)-ergosta-7, 22-dien-5alpha, 6beta-diol (2) on the basis of chemical and spectroscopic means ((1)H NMR, (13)C NMR, HMQC, HMBC, MS, and IR). This is the first example of isolation of a polyhydroxylated ergosterol glucoside from higher fungi in nature.     

Regulation of partitioned sterol biosynthesis in Saccharomyces cerevisiae.

Using yeast strains with null mutations in structural genes which encode delta-aminolevulinic acid synthetase (HEM1), isozymes of 3-hydroxy-3-methylglutaryl coenzyme A (HMG1 and HMG2), squalene epoxidase (ERG1), and fatty acid delta 9-desaturase (OLE1), we were able to determine the effect of hemes, sterols, and unsaturated fatty acids on both sterol production and the specific activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) in Saccharomyces cerevisiae. We found that the HMGR isozymes direct essentially equal amounts of carbon to the biosynthesis of sterols under heme-competent conditions, despite a huge disparity (57-fold) in the specific activities of the reductases. Our results demonstrate that palmitoleic acid (16:1) acts as a rate-limiting positive regulator and that ergosterol acts as a potent inhibitor of sterol production in strains which possess only the HMGR1 isozyme (HMG1 hmg2). In strains which contain only the HMGR2 isozyme (hmg1 HMG2), sterol production was inhibited by oleic acid (18:1) and to a lesser degree by ergosterol. The specific activities of the two reductases (HMGR1 and HMGR2) were found to be differentially regulated by hemes but not by ergosterol, palmitoleic acid, or oleic acid. The disparate effects of unsaturated fatty acids and sterols on these strains lead us to consider the possibility of separate, compartmentalized isoprenoid pathways in S. cerevisiae.     

Quantification of plasma membrane ergosterol of Saccharomyces cerevisiae by direct-injection atmospheric pressure chemical ionization/tandem mass spectrometry

A method for the quantification of ergosterol by atmospheric pressure chemical ionization (APcI) mass spectrometry with direct injection is described. Ergosterol and squalene were ionizable with methanol as the carrier solvent. Using positive-mode tandem mass spectrometry (MS/MS), ergosterol could be identified unambiguously without interference from structurally related compounds such as lanosterol, cholesterol, and squalene. Molecular ions of ergosterol, lanosterol, and cholesterol were detected as the [M + H - H(2)O](+) ion species, while squalene appeared as the [M + H](+) ion species. Upon fragmentation of the three sterols and squalene, the product ion at m/z 69 was present as one of the major fragments in all four compounds. This product ion was used for the quantification of ergosterol in multiple-reaction-monitoring acquisition mode. The relationship between signal intensity and ergosterol concentration was linear over the concentration range of 0.15 to 5 microg/ml, or 7. 56-252 pmol ergosterol per 20 microl injection. The plasma membrane ergosterol of the yeast Saccharomyces cerevisiae could be quantified reproducibly without the need for prior separation from other lipids or derivatization. Six repeated injections of ergosterol standards at concentrations of 0.95 and 4.25 microg/ml gave standard deviations of 0.031 and 0.084, respectively, and coefficients of variation of 3.33 and 1.98%, respectively. The coefficient of variation for the four independently extracted membrane ergosterol samples was 11.18%. The presence of other lipids in a crude lipid extract did not interfere with the ergosterol determination. Direct injection APcI with multiple reaction monitoring is aconvenient and sensitive method for ergosterol quantification requiring no prior fractionation.     

Selective destruction of microscopic fungi through photo-oxidation of ergosterol

Ergosterol is an important component of fungal membranes. This sterol can be easily transformed to peroxide of ergosterol by photo-oxidation with singlet oxygen. Cultures of Papalauspora immersa were grown on Czapeck agar medium, and subjected to the following conditions: 1) irradiation with daylight and quartz light (excluding UV light), 2) addition by diffusion of yellowish eosine (0.1 mg/mL), and 3) the control (no yellowish eosine, under darkness conditions). Fungal growth was completely inhibited after the treatment with quartz light (3 h) and yellow eosine, and no growth was observed in subsequent subcultures. These results suggested that plasma membrane components changed significantly by the transformation of ergosterol to peroxide of ergosterol leading to fungal death. To confirm this, a second experiment on a larger scale was carried out in which the fungus was grown on liquid medium in test tubes, treated, irradiated, and tested for peroxide of ergosterol by (1)HNMR. This peroxide was only found in treated samples. These findings represent a new strategy for developing antifungal agents, based on ergosterol photo-oxidation which might probably be related to the disruption of the plasma membrane, instead of only preventing the ergosterol biosynthesis. The potential application of this strategy for the selective control or prevention of pathogenic fungi is considerable.     

A new ceramide from Suillus luteus and its cytotoxic activity against human melanoma cells

A new phytosphingosine-type ceramide, suillumide (1), was isolated from the EtOH extract of the basidiomycete Suillus luteus (L.) S. F. Gray, along with ten known compounds: ergosta-4,6,8(14),22-tetraen-3-one, ergosterol, ergosterol peroxide, suillin, (E)-3,4,5-trimethoxycinnamic alcohol, 5 alpha,6 alpha-epoxyergosta-8,22-diene-3beta,7 beta-diol, (R)-1-palmitoylglycerol, ergosta-7,9(11),22-triene-3beta,5 alpha,6 beta-triol, cerevisterol, and 4-hydroxybenzoic acid. The structure of 1 was determined on the basis of spectroscopic and mass-spectrometric analyses, as well as by chemical methods. Compound 1 and its synthetic diacetyl derivative 2 were tested for their cytotoxic activities against the human melanoma cell line SK-MEL-1. Both drugs showed IC(50) values of ca. 10 microM after 72 h of exposure.     

不同培养基和三种金属离子对桦褐孔菌培养菌丝体的羊毛甾醇和麦角甾醇积累的影响

Lanosterol and ergosterol are the active principles with potential pharmacological activities in Inonotus obliquus. However, the two sterols are less accumulated in cultured mycelia of the fungus. In this study, different carbon and nitrogen sources and pH levels together with three metal ions were assayed for their effects on accumulation of the two sterols in the fungus. Among the tested media the growth medium consisting of glucose (1.5%), rice powder (0.5%), yeast extract (0.4%), wheat bran (0.1%), KH2PO4 (0.01%) and MgSO4·7H2O (0.05%) with pH level at 6.5 yielded a maximum production of the two sterols, which can further be increased following the treatment of Ag+, Cu2+ and Ca2+. Supplementing Ag+ at concentrations of 0.28 and 0.35μmol partially inhibited ergosterol biosynthesis, leading to an enhanced accumulation of lanosterol, the presence of intermediates of ergosterol biosynthetic pathway and a reduced accumulation of ergosterol in cultured mycelia of I.     

The ergosterol biosynthesis inhibitor zaragozic acid promotes vacuolar degradation of the tryptophan permease Tat2p in yeast

Ergosterol is the yeast functional equivalent of cholesterol in mammalian cells. Deletion of the ERG6 gene, which encodes an enzyme catalyzing a late step of ergosterol biosynthesis, impedes targeting of the tryptophan permease Tat2p to the plasma membrane, but does not promote vacuolar degradation. It is unknown whether similar features appear when other steps of ergosterol biogenesis are inhibited. We show herein that the ergosterol biosynthesis inhibitor zaragozic acid (ZA) evoked massive vacuolar degradation of Tat2p, accompanied by a decrease in tryptophan uptake. ZA inhibits squalene synthetase (SQS, EC 2.5.1.21), which catalyzes the first committed step in the formation of cholesterol/ergosterol. The degradation of Tat2p was dependent on the Rsp5p-mediated ubiquitination of Tat2p and was not suppressed by deletions of VPS1, VPS27, VPS45 or PEP12. We will discuss ZA-mediated Tat2p degradation in the context of lipid rafts.     

Bioactive metabolites from Chaetomium globosum L18, an endophytic fungus in the medicinal plant Curcuma wenyujin

An endophytic fungus, strain L18, isolated from the medicinal plant Curcuma wenyujin Y.H. Chen et C. Ling was identified as Chaetomium globosum Kunze based on morphological characteristics and sequence data for the internal transcribed spacer (ITS-5.8S-ITS2) of the nuclear ribosomal DNA. A new metabolite named chaetoglobosin X (1), together with three known compounds erogosterol (2), ergosterol 5α,8-peroside (3) and 2-methyl-3-hydroxy indole (4), were isolated from C. globosum L18. Their structures were elucidated by spectroscopic methods including NMR, UV, IR and MS data and comparison with published data. Chaetoglobosin X (1) is hitherto unknown, whereas 2-methyl-3-hydroxy indole (4) is reported for the first time as a fungal metabolite, and erogosterol (2) and ergosterol 5α,8-peroside (3) are known fungal metabolites previously identified in other genera. Chaetoglobosin X (1) exhibited a broader antifungal spectrum and showed the strongest cytotoxic activity against H22 and MFC cancer cell lines.     

Total and Free Ergosterol in Mycelia of Saltmarsh Ascomycetes with Access to Whole Leaves or Aqueous Extracts of Leaves

Three species of saltmarsh ascomycetes were grown in the presence of all of the constituents of their natural substrate (leaves of cordgrass) or were presented only with aqueous extracts of the leaves. These two growth-condition treatments had no significant effect on total ergosterol content of the fungal mycelia, contrary to an earlier hypothesis that availability of plant lipids would lower fungal ergosterol contents. Mycelial content of free ergosterol was about twice as variable as that for total (free plus esterified) ergosterol. Total ergosterol (data pooled for all species) was strongly correlated to organic mycelial mass (r² = 0.43, P < 0.00001, and slope = 4.59 μg of ergosterol mg of organic mass^-1).