New species of <Emphasis Type="Italic">Clohiesia</Emphasis> and <Emphasis Type="Italic">Paraniesslia</Emphasis> collected from freshwater habitats in China

Two fungi collected from submerged woody debris were found to represent hitherto undescribed species of the ascomycete genera Clohiesia and Paraniesslia. They are described as Clohiesia curvispora sp. nov. and Paraniesslia aquatica sp. nov. based on morphological characters. Clohiesia curvispora is characterized by immersed ascomata under a clypeus, and unitunicate, cylindrical asci containing one-celled, curved, elongate-fusiform ascospores. Paraniesslia aquatica is characterized by small, superficial, setose ascomata, and unitunicate, clavate asci containing verrucose, brown ascospores. Each species is illustrated with light micrographs and compared with similar taxa in this article.     

Cellulase activity of some phytopathogenic fungi isolated from diseased leaves of broad bean

Forty-five fungal species and two varieties belonging to the 23 genera were collected from 50 samples of diseased leaves of broad bean collected from Qena Governorate in Egypt on glucose-Czapek’s, dichloran-chloramphenicol-malt extract and dichloran-chloramphenicol-peptone agar at 28 °C. The most common genera were Alternaria, Aspergillus, Cladosporium, Fusarium, Mycosphaerella and Penicillium. The most prevalent species were Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, Cladosporium cladosporioides, Fusarium merismoides, Mycosphaerella tassiana and Penicillium chrysogenum. Among the eight dematiaceous Hyphomycetes phytopathogenic fungi screened for their abilities to produce both exo- and endo-β-1,4-glucanase enzymes (C₁ and C_x), five species had high C₁ enzyme production and two species had high C_x enzyme production. However, two and three species were moderately active in producing C₁ and C_x enzymes, respectively. The remaining species had low production of both C₁ and C_x enzymes. The highest cellulase activity was recorded by Alternaria citri and Cochliobolus spicifer for C₁ and by A alternata and A. citri for C_x enzyme. Maximum production of C₁ enzyme by A. citri and C. spicifer was obtained after six days of incubation at 30 °C with an initial pH of 6 in a culture medium containing lactose and calcium nitrate as the carbon and nitrogen sources, respectively. The highest C_x enzyme production was by A. alternata and A. citri,which was recorded after eight days of incubation at 30 °C with an initial pH of 6 in a culture medium containing carboxymethyl cellulose and sodium or calcium nitrate as the carbon and nitrogen sources, respectively.     

Molecular characterization and antimicrobial activity of endophytic fungi from coffee plants

Endophytic filamentous fungi from coffee plants (Coffea arabica and C. robusta) deposited in the Brazilian Collection of Environmental and Industrial Microorganisms (CBMAI) were characterized taxonomically by using molecular tools and investigated concerning their antimicrobial activity against different human pathogenic bacteria. Thirty-seven out of 39 CBMAI strains investigated were identified to at least at genus level by ITS and rDNA D1/D2 sequencing and phylogenetic analyses. Bioactivity screening of fungal extracts against Salmonella choleraesuis (CBMAI 484), Staphylococcus aureus (CBMAI 485), Pseudomonas aeruginosa (CBMAI 489) and against four different Escherichia coli serotypes showed that 17 fungi inhibited at least one of the bacteria studied. The endophytic fungi Trichoderma harzianum (CBMAI 43), Guignardia sp. (CBMAI 69) and Phomopsis sp. (CBMAI 164) inhibited from four to five bacterial species, while five fungi were active against all pathogenic bacteria tested and were identified as Aspergillus versicolor (CBMAI 46), Fusarium oxysporum (CBMAI 53), Glomerella sp. (CBMAI 63) and Cladosporium spp. (CBMAI 64 and CBMAI 66). The Minimal Inhibitory Concentration (MIC) for the fungus extracts varied from 0.025 to 1.0 mg ml⁻¹, demonstrating antimicrobial potential of some of these fungi.     

喜树内生真菌的分离及其抗肿瘤活性代谢产物的筛选方法

从喜树(Camptotheca acuminata Decne.)的根、枝条、叶和果实中分离纯化了48株内生真菌,通过对各个菌株的少量发酵培养,HPLC分析结合色谱峰紫外扫描检测方法,以紫外扫描图谱的相似性为依据,对喜树内生真菌产生喜树碱结构类似物进行初步筛选,并进一步以抑瘤实验确证其抗肿瘤活性.结果证明,以该方法筛选到的10个内生菌株中有7个菌株发酵液对HL-60细胞增殖具有显著的抑制活性.相对于常规的生物活性筛选,高效液相色谱结合色谱峰紫外光谱的方法,在药用植物内生真菌活性次生代谢产物筛选研究中具有快速、高效的特点.     

利用黄粉虫分离土壤昆虫病原真菌

利用黄粉虫Tenebrio molitorL.作为寄主从土壤中诱感并分离昆虫病原真菌。结果显示,从吉林市的18个土样中分离出球孢白僵菌(Beauveria bassiana)、金龟子绿僵菌(Metarhiziumanisopliae)和玫烟色拟青霉(Paecilomyces fumosoroseus)。土样中的昆虫病原真菌检出率为77.78%。这表明利用黄粉虫分离土壤中的昆虫病原真菌是一种简单、有效的方法。     

灰毛豆内生真菌淡紫拟青霉菌(TPL04)代谢产物的研究

从灰毛豆叶片中分离出内生真菌-淡紫拟青霉菌Purureocillium lilacinum(TPL04),对其发酵产物采用硅胶柱色谱、Sephadex LH-20凝胶色谱、制备薄层色谱、中压柱色谱及制备液相色谱等方法进行分离纯化,共获得8个单体化合物。通过波谱学方法并结合相关文献数据比对,化合物结构鉴定为5-羟基己酸-4-内酯(1)、(R)-4-苄基-2-噁唑烷酮(2)、2′-脱氧胸苷(3)、对羟基苯甲酸甲酯(4)、光色素(5)、β-胡萝卜苷(6)、尿嘧啶核苷(7)、己六醇(8)。其中化合物1、2、4是首次从淡紫拟青霉菌中分离得到,抑菌实验表明化合物4对水稻纹枯菌(Pellicularia sasakii)、辣椒疫霉菌(Phytophthora capsici)、草莓灰霉菌(Botrytis cinerea)、油菜菌核菌(Sclerotinia sclerotiorum)四种植物病原菌生长有抑制作用。     

Study of antifungal activities of seven essential oils from some Iranian medicinal plants against various postharvest phytopathogenic fungi

The aim of this study was to find the antifungal activities of seven essential oils from some Iranian medicinal plants that have maximum (100%) inhibition effect on the mycelium growth of postharvest phytopathogenic fungi. Among 20 examined species belonging to three families, only 7 species could stop the mycelium growth of phytopathogenic fungi. The selected plants include Trachyspermum ammi, Zataria multiflora Boiss., Satureia hortensis, Caryophillum aromaticus, Menthe piperita, Cuminum cyminum L. and Carum carvi, and fungi include Aspergillus flavus, Botrytis cinerea, Penicillium italicum, Penicillium expansum, Penicillium commune, Rhizopus stolonifer and Rhizopus lyococcus. The results showed that the essential oil of these plants could stop the mycelium growth at 500 ppm, but could not completely inhibit the spore germination, however reduced the spore germination to 80–90%. Among the fungi Rhizopus stolonifer and Rhizopus lyococcus are more resistant to the inhibition effects of essential oils. Among the plants, Cuminum cyminum L. and Carum carvi were slightly weaker than other plants. Also except for Cuminum cyminum L. and Carum carvi, the essential oils of other plants had fungicide effect while these two plants in most cases had fugistatic effect. The results showed that these essential oils can be used as an effective alternative control method.     

Biological activities from extracts of endophytic fungi isolated from Viguiera arenaria and Tithonia diversifolia

A total of 39 endophytic fungi have been isolated from Viguiera arenaria and Tithonia diversifolia, both collected in S?o Paulo State, Brazil. The isolates were identified based on their ribosomal DNA sequences. The ethyl acetate (EtOAc) extracts of all endophytic fungi were evaluated for their antimicrobial, antiparasitic and antitumoral activity. Antimicrobial screening was conducted using an agar diffusion assay against three pathogenic microorganisms: Staphylococcus aureus, Escherichia coli and Candida albicans. Antiparasitic activity was determined by enzymatic inhibition of gGAPDH of Trypanosoma cruzi and adenine phosphorybosiltransferase (APRT) of Leishmania tarentolae. Antitumoral activity was tested against human T leukemia cells by the Mosmann colorimetric method. All extracts showed activity in at least one assay: 79.5% of the extracts were cytotoxic against leukemia cells, 5.1% of the extracts were active against S. aureus, 25.6% against E. coli and 64.1% against Candida albicans. Only one extract showed promising results in the inhibition of parasitic enzymes gGAPDH (95.0%) and three were found to inhibit APRT activity. The cytotoxic extract produced by the strain VA1 (Glomerella cingulata) was fractionated and yielded nectriapyrone and tyrosol. Nectriapyrone showed relevant cytotoxic activity against both human T leukemia and melanoma tumor cell lines.     

Activity of dehydroabietic acid derivatives against wood contaminant fungi

The antifungal activity of 10 dehydroabietic acid derivatives with different configuration in A and B rings (cis/trans A/B junction) and different substituents and/or functionalities was evaluated in bioassays in vitro and in situ (pine wood blocks).

The test compounds dissolved in acetone were assayed at several concentrations w/w (test compound/culture medium) against the fungi. The Relative Inhibition (RI) was determined by measuring the radial growth of colonies of the fungi treated with the test compounds by comparison with those of control cultures; the results are expressed as EC₅₀.

The results of bioassays in vitro have shown that hydroxyl and aldehyde functions are required for antifungal activity in this group of compounds and deisopropylation can increase the activity. Our assay of antifungal activity in situ (in pine wood blocks) provides a means to investigate the preservative activities of these antifungal compounds under actual conditions of use.

The dehydroabietic acid derivative cis-deisopropyldehydroabietanol (10) inhibited the growth of several of the fungi tested, in vitro and in situ.

The results obtained in situ with the test compound (10) at 6% and 8% were not significantly different from the reference products and a good level of protection of the wood against the organisms tested was achieved.

The results in wood bioassays present new possibilities in the search for natural new compounds in the wood protection, as an alternative to conventional fungicides.     

Antifungal activity of a novel compound from Burkholderia cepacia against plant pathogenic fungi

AIMS: To investigate antifungal activity of a novel compound (named as CF66I provisionally) against plant pathogenic fungi, mainly including Fusarium sp., Colletotrichum lindemuthianum, Rhizoctonia solani, etc. METHODS AND RESULTS: Minimal inhibition concentrations (MIC) and minimal fungicidal concentrations (MFC) of CF66I for each fungi were determined using serial broth dilution method. The data demonstrated MIC ranged from 2.5 to 20.0 microg ml(-1) and MFC were shown at levels of < or =7.5 microg ml(-1) except Fusarium sp. With reverse microscopy, profound morphological alterations of fungal cells were observed after exposure to CF66I. Conidiospores were completely inhibited, and protoplasm aggregated to form chalamydospores because of the changes of cell permeability. Some chalamydospores were broken, suggesting the compound probably possessed strong ability of damaging the cell wall. In addition, CF66I was investigated for its antifungal stability against Curvularia lunata. The results showed CF66I kept strong fungi-static activity over-wide pH range (pH 4-9) and temperature range (from -70 to 120 degrees C). CONCLUSIONS: The compound CF66I exhibited strong and stable broad-spectrum antifungal activity, and had a significant fungicidal effect on fungal cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Results from prebiocontrol evaluations performed to date are probably useful in the search for alternative approaches to controlling serious plant pathogens.     

Keratinophilic fungi isolated from children's sandpits in the Nablus area,West Bank of Jordan

The keratinophilic fungi of 29 sandpits from kindergarten schools and public parks in the city of Nablus was analysed to evaluate their role in the epidemiology of diseases caused by these fungi. Seventy two species were recovered 28 of which were common to both kindergartens and public parks sandpits. High percentage (57.4%) of fungal isolates found had been identified as the causes of various types of mycoses. Eight species of dermatophytes and closely related fungi were recovered, of which the followings were the most commonly found species in sandpits: Chrysosporium keratinophilum (20.7%), Microsporum gypseum (17.2%), Trichophyton mentagrophytes (6.9%), and C. evolceanui (6.9%).     

Fibrinolytic activity of some fungi isolated from self-heated composted fertilizer

Mesophilic fungi isolated from organic fertilizer compost samples accounted for 70.94% of the total fungal count, while thermophilic and thermotolerant fungi constituted 29.05% of that count. Eight mesophilic fungal species, namelyAspergillus niger, Monilia sitophila, Paecilomyces divaricata, Penicillium chrysogenum, P. fellutanum, Scopulariopsis brevicaulis, S. brumptii andZygorhynchus japonicus; two thermophilic fungiHumicola grisea andOidiodendron flavum and three thermotolerant speciesAspergillus fumigatus, Thermomyces lanuginosus andZygorhynchus vuilleminii were isolated during the study. Most of the tested fungi showed a proteolytic activity and liquified gelatin in the test tube method and in cup plates. The thermophilic fungusO. flavum was the most potent proteolytic fungus. The comparative fibrinolytic assay revealed the following sequence in the ability of the tested fungi to hydrolyse fibrin:O. fiavum>S. brevicaulis>H. grisea>A. fumigatus>T. lanuginosus.     

Structure-activity relationships of ganoderma acids from Ganoderma lucidum as aldose reductase inhibitors

A series of lanostane-type triterpenoids, known as ganoderma acids were isolated from the fruiting body of Ganoderma lucidum. Some of these compounds were identified as active inhibitors of the in vitro human recombinant aldose reductase. To clarify the structural requirement for inhibition, some structure–activity relationships were determined. Our structure–activity studies of ganoderma acids revealed that the OH substituent at C-11 is an important feature and the carboxylic group in the side chain is essential for the recognition of aldose reductase inhibitory activity. Moreover, double bond moiety at C-20 and C-22 in the side chain contributes to improving aldose reductase inhibitory activity. In the case of ganoderic acid C2, all of OH substituent at C-3, C-7 and C-15 is important for potent aldose reductase inhibition. These results provide an approach to understanding the structural requirements of ganoderma acids from G. lucidum for aldose reductase inhibitor. This understanding is necessary to design a new-type of aldose reductase inhibitor.     

Antifungal activity of extracts from Atacama Desert fungi against Paracoccidioides brasiliensis and identification of Aspergillus felis as a promising source of natural bioactive compounds

Fungi of the genus Paracoccidioides are responsible forparacoccidioidomycosis. The occurrence of drug toxicity and relapse in this diseasejustify the development of new antifungal agents. Compounds extracted from fungalextract have showing antifungal activity. Extracts of 78 fungi isolated from rocks ofthe Atacama Desert were tested in a microdilution assay againstParacoccidioides brasiliensis Pb18. Approximately 18% (5) of theextracts showed minimum inhibitory concentration (MIC) values≤ 125.0µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the bestresults, with an MIC of 15.6 µg/mL. This isolate was identified asAspergillus felis (by macro and micromorphologies, and internaltranscribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and wasgrown in five different culture media and extracted with various solvents to optimiseits antifungal activity. Potato dextrose agar culture and dichloromethane extractionresulted in an MIC of 1.9 µg/mL against P. brasiliensis and did notshow cytotoxicity at the concentrations tested in normal mammalian cell (Vero). Thisextract was subjected to bioassay-guided fractionation using analyticalC18RP-high-performance liquid chromatography (HPLC) and an antifungal assay usingP. brasiliensis. Analysis of the active fractions by HPLC-highresolution mass spectrometry allowed us to identify the antifungal agents present inthe A. felis extracts cytochalasins. These results reveal thepotential of A. felis as a producer of bioactive compounds withantifungal activity.     

Isolation of keratinolytic fungi from a coal mine dump

During the study of fungal succesion in the coal mine dump in Brzezinka (Poland), soil samples were examined for keratinolytic fungi. These micro-organisms were rather poorly represented in the area studied. Out of 300 soil samples examined, only 48 (16%) were positive for keratinolytic fungi.Trichophyton ajelloi andArthroderma curreyi were the prevailing species. These species occurred practically at two locations, i.e. on the naked carbon rocks inhabited by algae crops (chiefly byCyanophyta) and in the pine litter. It can be supposed that the occurrence of keratinolytic fungi was more dependent on the favourable general conditions such as increasing organic matter content, microflora, and humidity than on the presence of keratin remains in the soil. Because of the lack of potentially pathogenic fungi, the coal mine dump examined cannot be considered as an important source of fungal infection.