Antifungal activity of some Brazilian Hypericum species

Crude methanolic extracts and fractions from the aerial parts of seven species of Hypericum (H. caprifoliatum Cham. and Schltdl., H. carinatum Griseb., H. connatum Lam., H. ternum A. St.-Hil., H. myrianthum Cham. and Schltdl., H. piriai Arechav. and H. polyanthemum Klotzsch ex Reichardt) growing in southern Brazil were analyzed for their in vitro antifungal activity against a panel of standardized and clinical opportunistic pathogenic yeasts and filamentous fungi, including dermatophytes, by the agar dilution method. Chloroform and hexane extracts of H. ternum showed the greatest activity among extracts tested.     

Antimicrobial activity of some Hypericum species

The crude methanolic extracts of six species of Hypericum [H. caprifoliatum Cham. & Schlecht., H. carinatum Griseb., H. connatum Lam., H. ternum A. St. Hil., H. myrianthum Cham. & Schlecht. and H. polyanthemum Klotzsch ex Reichardt] growing in southern Brazil were analyzed for antimicrobial activity against several microorganisms (bacteria and fungi). The most active plant was H. caprifoliatum, which showed activity against Staphylococcus aureus. Only H. polyanthemum and H. ternum extracts were active against Bacillus subtilis. None of the crude methanolic extracts showed activity against S. epidermidis, Escherichia coli or Saccharomyces cerevisiae. Extracts from these species were evaluated chemically and tannin, flavonoid and phenolic acids were the prominent compounds. The plants contained quercitrin, hyperoside (except H. connatum) and, less frequently, isoquercitrin and chlorogenic acid. In contrast to H. perforatum, which has high concentrations of rutin, these species do not produce this flavonoid or it appears as traces. The tannin concentration varied between 5.1 and 16.7% in H. myrianthum and H. ternum, respectively.     

Alkylbenzoquinones with antiproliferative effect against human cancer cell lines from stem of Ardisia kivuensis

Two new alkylbenzoquinone derivatives, named as ardisiaquinone J (1) and K (2) were isolated from the MeOH extract of the stem of Ardisia kivuensis Taton (Myrsinaceae), together with the known lupeol and β-sitosterol. Their structures were elucidated on the basis of spectroscopic analysis and comparison with authentic samples. The new compounds exhibited considerable antiproliferative activity against Ishikawa, HeLa, MCF7 and A431 cell lines with IC₅₀ values between 6.64 and 15.40 μM. In addition, compound 2 exerted a moderate free radical scavenging effect on DPPH-assay.     

Antiosteoporotic activity of phenolic compounds from Curculigo orchioides

Six phenolic compounds isolated from Curculigo orchioides, including 2,6-dimethoxy benzoic acid (1), curculigoside A (2), curculigoside B (3), curculigine A (4), curculigine D (5) and 3,3′,5,5′-tetramethoxy-7,9′:7′,9-diepoxylignan-4,4′-di-O-β-d-glucopyranoside (6), together with the ethanol extract of Curculigo orchioides were evaluated for their activity on osteoblasts in neonatal rat calvaria cultures and multinucleated osteoclasts derived from rat marrow cells so as to characterize the antiosteoporotic components of this plant and explore the relationship of chemical structure with antiosteoporotic activity. The proliferation of osteoblast was assayed by MTT methods. The activity of ALP (alkaline phosphatase) and TRAP (tartrate-resistant acid phosphatase) was measured by p-nitrophenyl sodium phosphate assay. The TRAP stain was used to identify osteoclast in morphology. The resorption pit area on the bone slices formed by osteoclast was measured by computer image processing. The ethanol extract exhibited stimulatory effect on both the osteoblast proliferation and the ALP activity. Six compounds all increased the osteoblast proliferation, and compounds (1), (2) and (4) also slightly increased the osteoblastic ALP activity. Compounds (1), (2), (3), (6) and the ethanol extract decreased area of bone resorption pit, osteoclastic formation and TRAP activity. These results indicated that phenolic compounds are antiosteoporotic chemical constituents from Curculigo orchioides, and their activities are related with chemical structures.     

Composition and antimicrobial activity of the essential oil of six Hypericum species from Serbia

The volatile composition of six Hypericum species has been studied. The essential oils were obtained by steam distillation in 500 mL H₂O for 2 h in a modified Clevenger apparatus with a water-cooled oil receiver to reduce hydrodistillation over-heating artifacts, and their analyses were performed by GC and GC–MS. Identification of the substances was made by comparison of mass spectra and retention indices with literature records. A total of 100 different compounds were identified. The main constituents of the investigated populations of each taxon have been revealed as follows: Hypericum alpinum: (−)-β-pinene, γ-terpinene, (−)-(E)-caryophyllene; Hypericum barbatum: (−)-α-pinene, (−)-β-pinene, (−)-limonene, (−)-(E)-caryophyllene, (−)-caryophyllene oxide; Hypericum rumeliacum: (−)-α-pinene, (−)-β-pinene, (−)-limonene, Hypericum hirsutum: nonane, undecane, (−)-(E)-caryophyllene, (−)-caryophyllene oxide; Hypericum maculatum: spathulenol, globulol; Hypericum perforatum: (−)-α-pinene, (Z)-β-farnesene, germacrene D; Monoterpene hydrocarbons were shown to be the main group of the taxa belonging to the section Drosocarpium, while the taxa of section Hypericum were more rich in sesquiterpene hydrocarbons.     

Chemistry and bioactivity of Raulinoa echinata Cowan, an endemic Brazilian Rutaceae species

The hexane extract of the stems of Raulinoa echinata afforded the sesquiterpenes germacrene D (6), 1beta,6alpha-dihydroxy-4-(15)-eudesmene (4) and oplopanone (5); the triterpenes squalene, isomultiflorenol (7), isobauerenol (8) and friedelin (9); the protolimonoids melianone (2) and melianodiol (3); and the pyranocoumarin 3-(1'-1'-dimethylallyl)-lomatin (1), which has not been reported previously as a natural product; together with beta-sitosterol. The hexane extract and some of these compounds were assayed in vitro against trypomastigote forms of Trypanosoma cruzi. Brine shrimp lethality and antimicrobial activities of the crude extract and pure compounds were also evaluated.     

银合欢豆荚中的酚类化学成分

为探讨银合欢(Leucaena leucocephala)的化学成分,从银合欢豆荚乙醇提取物中分离得到7个酚类化合物,经过波谱分析,鉴定为原儿茶酸乙酯(1)、丁香酸(2)、3-羟基-1-(3-甲氧基-4-羟基苯基)丙烷-1-酮(3)、咖啡酸甲酯(4)、(Z)-对香豆醛(5)、3-甲氧基-4-羟苯丙烷-7,8,9-三醇(6)、愈创木基甘油-8-O-4′-芥子醇醚(7)。所有化合物均为首次从该植物中分离得到。化合物1对大肠杆菌和鼠伤沙门氏菌有一定的抑制活性。     

三孢布拉霉crgA启动子的克隆和活性分析

【背景】CrgA是三孢布拉霉(Blakesleatrispora,Bt)中调控类胡萝卜素合成的关键负调控因子,其表达水平会影响类胡萝卜素的合成。【目的】克隆三孢布拉霉crgA启动子并分析其活性,为进一步解析CrgA表达调控机制奠定基础。【方法】通过综合微生物基因组(integrated microbial genomes, IMG)数据库提供的基因组序列,克隆crgA翻译起始位点上游2 000 bp序列,分析其顺式调控元件和转录起始区域预测,通过RT-qPCR分析不同光照时间对三孢布拉霉crgA相对转录水平的影响;构建4个不同长度的crgA启动子截短序列驱动的GUS-mGFP5重组表达载体p1303-procrgAF、F1、F2和F3,利用农杆菌侵染整合到三孢布拉霉基因组中,在黑暗和光照条件下测定β-D-葡萄糖苷酸酶(β-D-glucuronidase,GUS)酶活性并观察荧光信号。【结果】crgA启动子不仅包含基础的TATA-box和CAAT-box元件,还包括多个与光响应相关的元件。观察荧光结果显示CaMV35S和构建的4个突变启动子均能在三孢布拉霉体内驱动下游基因表达,检测GUS...     

Synthesis and evaluation of bioactive naphthoquinones from the Brazilian medicinal plant, Tabebuia avellanedae

A series of naphthoquinones based on the naphtho[2,3-b]furan-4,9-dione skeleton such as (−)-5-hydroxy-2-(1′-hydoxyethyl)naphtho[2,3-b]furan-4,9-dione (1) and its positional isomer, (−)-8-hydroxy-2-(1′-hydoxyethyl)naphtho[2,3-b]furan-4,9-dione (2), which are secondary metabolites found in the inner bark of Tabebuia avellanedae, were stereoselectively synthesized and their biological activities were evaluated in conjunction with those of their corresponding enantiomers. Compound 1 exhibited potent antiproliferative effect against several human tumor cell lines, but its effect against some human normal cell lines was much lower than that of mitomycin. On the other hand, its enantiomer (R)-1 was less active toward the above tumor cell lines than 1. The antiproliferative effect of 2 against all tumor cell lines was significantly reduced. These results indicated the presence of the phenolic hydroxy group at C-5 is of great important for increasing antiproliferative effect. In addition, 1 also showed higher cancer chemopreventive activity than 2, while there were no significant differences between 1 and 2 in antimicrobial activity. Both compounds displayed modest antifungal and antibacterial activity (Gram-positive bacteria), whereas they were inactive against Gram-negative bacteria.     

A prenylated xanthone and antiproliferative compounds from leaves of Pentadesma butyracea

A new prenylated xanthone, butyraxanthone F (1) together with 20 known compounds were isolated from the leaves of Pentadesma butyracea. Their identification was achieved by spectroscopic means and comparison of the data with literature or by direct comparison on TLC with authentic samples. To the best of our knowledge, this is the first report of 2-hydroxy-2,3-dihydrosqualene (17) from a natural source. Compounds 2–6 and 11–16 were found for the first time in this genus. The antiproliferative activity of the crude extract, fractions and some isolated compounds was evaluated against three human cancer cell lines, BGC-823, Hela and A549. The crude extract, fractions B and C showed weak activities. Globuxanthone (2) and 30-epi-cambogin (7) were found to be the most active compounds on the three cancer cells. The effect of 2 on Hela cells and that of 7 on BGC-823 cells were noteworthy. The antiproliferative potential of allanxanthone A (3), ergosta-4,6,8(14),22-tetraen-3-one (14) and 2-hydroxy-2,3-dihydrosqualene (17) against BGC-823 and Hela cells could be classified as moderate-to-weak.     

Prosthecium species with Stegonsporium anamorphs on Acer

Data from microscopic morphology, single-spore cultures, and DNA analyses of teleomorphs and anamorphs support the recognition of five species of Prosthecium with Stegonsporium anamorphs on Acer: P. acerinum sp. nov., the teleomorph of S. acerinum; P. acerophilum comb. nov., formerly known as Dictyoporthe acerophila; P. galeatum comb. nov., originally described as Massaria galeata; P. opalus sp. nov.; and P. pyriforme sp. nov., the teleomorph of S. pyriforme s. str. The morphology of both type specimens and freshly collected material was investigated. The teleomorphs have brown ellipsoidal ascospores with five distosepta and often a longitudinal distoseptum. The anamorphs of all species described here belong to Stegonsporium; their connection to the Prosthecium teleomorphs was demonstrated by morphology and DNA sequences of single spore cultures derived from both ascospores and conidia. The anamorphs and teleomorphs of all five Prosthecium species are described and illustrated by LM images, and a key to these species is provided. As perceived from this work, S. pyriforme is restricted to Europe and does not occur in North America, whereas S. acerinum is restricted to North America, not found in Europe. The host associations given in the literature are revised and evidence is provided that only A. opalus, A. pseudoplatanus, and A. saccharum are confirmed hosts of Prosthecium with Stegonsporium anamorphs. Molecular phylogenetic analyses of tef1, ITS rDNA, and partial nuLSU rDNA sequences confirm that the species with Stegonsporium anamorphs are closely related to P. ellipsosporum, the generic type species. Stilbospora macrosperma is confirmed as the anamorph of P. ellipsosporum by DNA data of single spore isolates obtained from both ascospores and conidia.     

New species of Phaeoramularia, Pseudocercospora and Stenella from Western Ghats of India

Four new species of the hyphomycete genera Phaeoramularia viz. Ph. caesalpinae, Pseudocercospora viz., Ps. tiliacearum, Stenella, viz. S. argyreiae and S. grewiae occurring on Caesalpinia bonducella Fleming (Caesalpiniaceae), Grewia sp. (Tiliaceae), Argyrea sp. Lour (Convolvulaceae) and Grewia sp. L. (Tiliaceae), respectively are described and illustrated here. All these fungi were collected from Western Ghats of India.     

Phytochemical, antimicrobial, antioxidant and antigenotoxic potentials of Cyperus rotundus extracts

The aqueous, ethyl acetate, methanolic and Total Oligomer Flavonoids (TOF) enriched extracts, obtained from the aerial parts of Cyperus rotundus, were investigated for their contents in phenolic compounds. Antioxidative activity using the NBT/riboflavin assay system, antimicrobial activity against Gram positive and Gram negative bacterial reference strains as well as antigenotoxic activity tested with the SOS chromotest assay were also studied. Significant antibacterial activity against reference strains; Staphylococcus aureus, Enterococcus faecalis, Salmonella enteritidis and Salmonella typhimurium, was detected in the presence of ethyl acetate and TOF enriched extracts. In addition to their antimicrobial activity, the same extracts showed a significant ability to inhibit nitroblue tetrazolium reduction by the superoxide radical in a non enzymatic O₂^.− generating system, and were also able to reduce significantly the genotoxicity induced by nifuroxazide and Aflatoxin B1. The antioxidant, antimicrobial and antigenotoxic activities exhibited by C. rotundus depend on the chemical composition of the tested extracts.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Seven new calochroid and fulvoid species of Cortinarius

We describe seven new European species of Cortinarius. All species are based on analyses of morphological and DNA sequence data. They all belong to a well-supported clade comprising most species traditionally treated in Cortinarius subgenus Phlegmacium sections Fulvi and Calochroi (i.e. the/Calochroi clade). All taxa are either fulvoid (containing anthraquinoid pigments) or calochroid (without these pigments). Morphological and ecological data are presented for all species and compared with similar species. A dichotomous key is presented for C. calochrous and similar species, including all six newly described calochroid species. The calochroid species C. albertii, C. chailluzii, C. cisticola, C. sancti-felicis, C. selandicus and C. vesterholtii spp. nov., and the fulvoid species C. langeorum sp. nov. are described.     

Synthesis and in vitro antiproliferative and antibacterial activity of new thiazolidine-2,4-dione derivatives

In our present research, we synthesised new thiazolidine-2,4-diones (12–28). All the newly synthesised compounds were evaluated for antiproliferative and antibacterial activity. Antiproliferative evaluation was carried out using normal human skin fibroblasts and tumour cell lines: A549, HepG2, and MCF-7. The IC₅₀ values were determined for tested compounds revealing antiproliferative activity. Moreover, safety index (SI) was calculated. Among all tested derivatives, the compound 18 revealed the highest antiproliferative activity against human lung, breast, and liver cancer cells. More importantly, the derivative 18 showed meaningfully lower IC₅₀ values when compared to the reference substance, irinotecan, and relatively high SI values. Moreover, newly synthesised compounds were screened for the bacteria growth inhibition in vitro. According to our screening results, most active compound was the derivative 18 against Gram-positive bacteria. Therefore, it may be implied that the novel compound 18 appears to be a very promising agent for anticancer treatment.     

环链虫草Cordyceps cateniannulata对番茄生长和抗氧化酶活性的影响

【目的】评估环链虫草Cordyceps cateniannulata对植物促生和植物抗氧化酶活性的影响。【方法】本研究利用浸种法将环链虫草接种于番茄植物体,在接种后的第30天和60天,通过番茄株高、根长、地上和地下部分的干鲜重指标评价其对番茄生长的影响;在接种后第10、20、30、60和90天,通过选择性培养基分析其在番茄不同组织中的生存情况,使用形态学及DNA序列比对的方法检验所分离菌株与原有菌株的一致性。在处理后的第30天,检测番茄叶片中的过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)及丙二醛(MDA)含量,观察环链虫草对番茄的抗氧化酶活性影响。【结果】环链虫草可定殖于番茄幼苗且对番茄生长有显著促进作用,菌株对植株的定殖偏好性分别为根部>茎部>叶部。酶活检测结果表明,处理组番茄叶片防御酶活性均呈显著升高的趋势,其中POD、CAT、SOD活性分别比对照增加了52.21%、75.31%和158.59%,MDA含量下降了35.15%。【结论】环链虫草可以通过浸种的方法感染并定殖番茄幼苗的根、茎、叶,促进番茄幼苗的生长并提高番茄抗氧化酶活性,具有较好的田间...