Research progress on natural products of fungi of Diaporthe sp / 中国中药杂志

Diaporthe sp. fungi is one of the important sources of active natural products. Polyketides, alkaloids, terpenes, anthraquinones and other types of novel metabolic products are found from this genus, and many of them have significant anti-tumor, antibacterial, anti-hyperlipidemia, inhibition of pulmonary fibrosis, antioxidant and other biological activities. This paper reviewed source, structure and biological activity of natural products from Diaporthe sp. in the past two decades, and provided a reference for in-depth study of natural product of this genus fungus and innovative drug development.

Row spacing, cultivar and fungicide application affect the incidence of soybean stem blight / Espaçamento entre linhas, cultivares e aplicação de fungicida afetam a incidência da seca da haste em soja

Brazil is a major soybean production country and cultivate yearly more than 36 million hectares. Several factors have been reported reducing soybean production and occurrence of diseases is one of the most important. Some diseases such as the pod and stem blight (Diaporthe phaseolorum var. sojae) can limit soybean yield by shortening plant cycle and reducing seed quality. Field experiments were conducted aiming to evaluate the effect of row spacing, soybean cultivar and fungicide application on the incidence of pod and stem blight on soybean. The trial was carried out twice, with planting date at 11/15/2012 and 12/15/2012, in Planaltina-DF, Brazil. Treatments were arranged in a split-split plot scheme obeying the randomized block design. The factors evaluated were row spacing (42, 60 and 75 cm), soybean cultivars ("Syn1180RR" and "Syn1080RR") and spray or not the fungicide Boscalid (500 g a.i./ha) at R1 and R3 soybean growth stages. Disease incidence was assessed on stems at the harvest time and on seeds after harvest and yield was estimated. Results obtained show that broader row spacing increased disease incidence on stems and seed, cultivar "Syn1180RR" was more susceptible than "Syn1080RR" and fungicide application reduced disease incidence. Pod and stem blight significantly reduced soybean yield.

O Brasil é um dos principais países produtores de soja e cultiva anualmente mais de 36 milhões de hectares. Diversos fatores têm sido relatados reduzindo a produção de soja e a ocorrência de doenças está entre os mais importantes. Algumas doenças como a seca da haste e da vagem (Diaporthe phaseolorum var. sojae) podem reduzir a produtividade pelo encurtamento do ciclo e redução na qualidade da semente. Experimentos de campo foram conduzidos com o objetivo de avaliar o efeito do espaçamento entre linhas, cultivares e aplicação de fungicida sobre a incidência da seca da haste e da vagem na soja. O experimento foi conduzido duas vezes, com semeadura da soja em 15/11/2012 e 15/12/2012, em Planaltina-DF, Brasil. Os tratamentos seguiram o esquema de parcelas sub-sub-divididas no delineamento de blocos ao acaso. Os fatores avaliados foram espaçamento entre linhas (42, 60 e 75 cm), cultivares de soja ("Syn1180RR" e "Syn1080RR") e aplicação ou não do fungicida Boscalida nos estádios R1 e R3 da soja. A incidência da doença em hastes e sementes e a produtividade da soja foram mensurados. Os resultados obtidos mostram que espaçamentos mais amplos favorecem maior incidência da doença em hastes e sementes, a cultivar "Syn1180RR" é mais suscetível do que a "Syn1080RR" e a aplicação de fungicida reduz a incidência da doença. A seca da haste e da vagem reduz significativamente a produtividade da soja

Fungal infection in a post-renal transplant patient with Diaporthe

Post-renal transplant fungal infections continue to be a major cause of mortality and morbidity. Universally reported fungi are Candida, especially Candida albicans, Cryptococcus, Aspergillus, Trichophyton rubrum and Pityriasis versicolor. Here, we report a case of infection caused by a rare fungus Diaporthe. It is an endophyte reported as plant pathogens and infrequently in humans and mammals. The patient was a renal transplant recipient on immunosuppressant. He had hypothyroidism and diagnosed with permanent pacemaker due to a complete heart block. The patient was treated with itraconazole (200 mg) successfully.

Secondary metabolites produced by endophytic fungi: novel antifungal activity of fumiquinone B

Fungi are present in the most diverse environments including the interior of plant tissues, living as endophytes without causing apparent damage. These endophytes are producers of secondary metabolites, also known as natural products, such as fungicides. Here, we evaluated the ethyl acetate fractions obtained from endophytic fungiisolated from plants in the genus Begonia. The fractions were submitted to inhibitorytest against the plant pathogens Diaporthe phaseolorum and Colletotrichum gloeosporioides. From the 88 ethyl acetate fractions evaluated, 14.7 % inhibited C. gloeosporioidesand 11.3 %inhibited D. phaseolorum. One fungal isolate displaying an active fraction was selected for chemical investigation. The fungus identified as Neopestalotiopsissp., produced a compound that was active against D. phaseolorum, with a MIC of 312 μg mL-1(1,695.3 μM). The compound was identified by mass spectrometry and 1H NMR as the known compound fumiquinone B. The results highlight that the endophytes are capable of producing compounds that may be used to control plant pathogens. The compound fumiquinone B is reported for the first time as an antifungal agent against D. phaseolorum, a relevant plant pathogen worldwide. This is also the first report of the production of fumiquinone B by the genus Neopestalotiopsis.

Selection, isolation, and identification of fungi for bioherbicide production

Abstract Production of a bioherbicide for biological control of weeds requires a series of steps, from selection of a suitable microbial strain to final formulation. Thus, this study aimed to select fungi for production of secondary metabolites with herbicidal activity using biological resources of the Brazilian Pampa biome. Phytopathogenic fungi were isolated from infected tissues of weeds in the Pampa biome. A liquid synthetic culture medium was used for production of metabolites. The phytotoxicity of fungal metabolites was assessed via biological tests using the plant Cucumis sativus L., and the most promising strain was identified by molecular analysis. Thirty-nine fungi were isolated, and 28 presented some phytotoxic symptoms against the target plant. Fungus VP51 belonging to the genus Diaporthe showed the most pronounced herbicidal activity. The Brazilian Pampa biome is a potential resource for the development of new and sustainable chemical compounds for modern agriculture.

Two Endophytic Diaporthe Species Isolated from the Leaves of Astragalus membranaceus in Korea

We characterized two endophyte fungi from the leaves of Astragalus membranaceus in Korea. The isolated strains were identified on the basis of the morphological characters and sequences analysis of the internal transcribed spacer and large subunit regions of the rDNA and β-tubulin gene. To the best of our knowledge, this is the first report of Diaporthe oncostoma and Diaporthe infecunda in Korea, and we have provided descriptions and figures.

Two new lactone derivatives from an endophyte Diaporthe sp. XZ-07 cultivated on Camptotheca acuminata / 中国中药杂志

To study the secondary metabolites and their cytotoxic activities of an endophytic fungus Diaporthe sp. XZ-07cultivated on Camptotheca acuminata. Colum chromatography by RP-18, Sephadex LH-20 and silica gel was used to isolate and purify the chemical constituent. Two new compounds were isolatedand identified as 5-((E)-1,4,5-trihydroxyhex-2-enyl)furan-2(5H)-one(1)and(5Z)-5-(2,3,4,5-tetrahydroxyhexylidene)furan-2(5H)-one(2)by spectroscopic analysis. Cytotoxic activities were evaluated by MTT method. Compound 1 showed strong inhibitory activity against Human cervical carcinoma cell line Hela, and compound 2 showed strong inhibitory activity against breast cancer cell line MCF-7, Human neuroblastoma SH-SY5Y and Lewis lung carcinoma cells 3LL.

Study on cytotoxic secondary metabolites of endophytic fungus Diaporthe longicolla A616 from Pogostemon cablin / 中国中药杂志

To study active secondary metabolites of endophytic fungus Diaporthe longicolla A616 isolated from Pogostemon cablin. Ten compounds were isolated from fermentation product of the strain 616 by silica gel, reverse phase silica gel, Sephadex-LH20, HPLC and so on. Their structures were identified as 1,3-diamino-1,3-dimethylurea(1),(7R,9R)-7-hydroxy-9-propyl-5-nonen-9-olide(2), Ergosta-5,7,22-trien-3β-ol(3),(22E,24R)-ergosta-4,6,8(14)-22-tetraen-3-one(4),(22E,24R)-3β,5α-dihydroxy-6β-ergosta-7,22-diene(5), citreoisocoumarin(6), glycerol monolinoleate(7), 1-(2-hydroxyethoxy)ethyl(E)-octadec-9-enoate(8), cyclo-(L-Pro-L-Ala)(9), cyclo(L)-Pro-(L)-Val(10), respectively, based on extensive spectroscopic analysis and literature comparisons. Compounds 6-10 were isolated from the genus Diaporthe for the first time. All isolated compounds were evaluated for in vitro cytotoxic activities against SF-268, MCF-7, NCI-H460 and HepG-2 tumor cell lines. Compounds 4 and 5 showed potent growth inhibitory activities against the four cell lines with IC₅₀ values of 5.3, 6.5, 12.2, 6.1μmol•L⁻¹ and 8.2, 5.2, 6.1, 9.4μmol•L⁻¹, respectively.

Chemical characterization of bioactive compounds from the endophytic fungus Diaporthe helianthi isolated from Luehea divaricata

Endophytic microorganisms, defined as fungi or bacteria that colonize the interior of plants without causing any immediate negative effects or damages, have reciprocal relationships with host plants. In some cases their presence is beneficial to the host due to the synthesis of bioactive compounds, among which several alcohols, esters, ketones and others that may react with other compounds and may be lethal to pathogenic microorganisms. Diaporthe helianthi (Phomopsis helianthi in its anamorphic phase) is available worldwide, especially in Europe, Asia and America. Isolated in Europe as an agent of the sunflower stem cancer, it has also been endophytically isolated from tropical and temperate plants. A D. helianthi strain isolated from Luehea divaricata has been employed in current research. An investigation of the secondary metabolite from D. helianthi by CC and NMR of ¹H and 13C yielded the separation of 10 fractions and the identification of the phenolic compound 2(-4 hydroxyphenyl)-ethanol (Tyrosol). Its antimicrobial reaction was tested and the ensuing antagonistic effects on the human pathogenic bacteria Enterococcus hirae, Escherichia coli, Micrococcus luteus, Salmonella typhi, Staphylococcus aureus, phytopathogenic Xanthomonas asc. phaseoli and phytopathogenic fungi were demonstrated. Results show that bioactive compounds and Tyrosol produced by D. helianthi have a biotechnological potential.