benzofurans and cyclopaldic-acid

Cyclopaldic acid is one of the main phytotoxic metabolites produced by fungal pathogens of the genus

Topics: Apoptosis; Arabidopsis; Ascomycota; Autophagy; Benzofurans; Proton-Translocating ATPases

Fungi are among the biotic agents that can cause deterioration of building stones and cultural heritage. The most common methods used to control fungal spread and growth are based on chemical pesticides. However, the massive use of these synthetic chemicals produces heavy environmental pollution and risk to human and animal health. Furthermore, their use is time dependent and relies on the repetition of treatments, which increases the possibility of altering building stones and culture heritage through environmental contamination. One alternative is the use of natural products with high antifungal activity, which can result in reduced toxicity and deterioration of archeological remains. Recently, three fungal strains, namely

Topics: Alternaria; Antifungal Agents; Aspergillus niger; Benzoates; Benzofurans; Biofilms; Biological Products; Bridged Bicyclo Compounds, Heterocyclic; Chromatography, High Pressure Liquid; Chromatography, Liquid; Diffusion; Fusarium; Italy; Magnetic Resonance Spectroscopy; Mass Spectrometry; Microbial Sensitivity Tests; Spectrometry, Mass, Electrospray Ionization

Aphids are noxious insect pests of major crops including cereals and legumes. Particularly, pea aphid (

Topics: Alcohols; Animals; Aphids; Benzofurans; Biological Control Agents; Fungi; Furans; Gliotoxin; Insect Repellents; Plants

Rusts are a noxious group of plant diseases affecting major economically important crops. Crop protection is largely based on chemical control. There is a renewed interest in the discovery of natural products as alternatives to synthetic fungicides for control. In this study we tested two fungal metabolites, namely cyclopaldic acid and epi-epoformin, for their effectiveness in reducing early stages of development of two major rust fungi from the genera Puccinia and Uromyces, P. triticina and U. pisi. Spore germination and appressorium formation were assessed on pretreated detached leaves under controlled conditions. Cyclopaldic acid and epi-epoformin were also tested in infected plants in order to evaluate the level of control achieved by treatments both before and after inoculation.. Cyclopaldic acid and epi-epoformin were strongly effective in inhibiting fungal germination and penetration of both rust species studied. This effect was not dose dependent. These results were further confirmed in planta by spraying the metabolites on plant leaves, which reduced fungal developmental of U. pisi and P. triticina at values comparable with those obtained by application of the fungicide.. Our results further demonstrate the potential of fungal metabolites as natural alternatives to synthetic fungicides for the control of crop pathogens of economic importance as rusts. © 2016 Society of Chemical Industry.

Topics: Basidiomycota; Benzofurans; Bridged Bicyclo Compounds, Heterocyclic; Fungicides, Industrial; Pisum sativum; Plant Diseases; Plant Leaves; Spores, Fungal; Triticum

Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. From a preliminary screening of fungal phytotoxins, cyclopaldic acid (1), seiridin (2), sphaeropsidin A (4), and papyracillic acid (5) were evaluated for their biting deterrent and larvicidal activities against Ae. aegypti L. Because compounds 1, 2, 4, and 5 exhibited mosquito biting deterrent activities and 1 and 4 demonstrated larvicidal activities, further structureactivity relationship studies were initiated on these toxins. In biting-deterrence bioassays, 1, 2, 4, and 5, 3,8-didansylhydrazone of cyclopaldic acid, 1F, 5-azidopentanoate of cyclopaldic acid A, 1G, the reduced derivative of cyclopaldic acid, 1 H, isoseiridin (3), 2'-O-acetylseiridin (2A), 2'-oxoseiridin (2C), 6-O-acetylsphaeropsidin A (4A), 8,14-methylensphaeropsidin A methyl ester (4B), and sphaeropsidin B (4C) showed activities higher than the solvent control. Sphaeropsidin B (4C) was the most active compound followed by 2A, while the other compounds were less active. Biting-deterrence activity of compound 4C was statistically similar to DEET. In the larvicidal screening bioassays, only compounds 1 and 4 demonstrated larvicidal activities. Based on LD50 values, compound 4 (LD50 36.8 ppm) was significantly more active than compound 1 (LD50 58.2 ppm). However, the activity of these compounds was significantly lower than permethrin.

Topics: Aedes; Animals; Benzofurans; Diterpenes; Furans; Insect Repellents; Insecticides; Larva; Saccharomycetales; Structure-Activity Relationship

From the endophytic fungus Pestalotiopsis sp. isolated from the leaves of the Chinese mangrove, Rhizophora mucronata, two novel hybrid sesquiterpene-cyclopaldic acid metabolites with an unusual carbon skeleton, named pestalotiopens A and B, were obtained, together with the already known phytotoxin altiloxin B. Pestalotiopen B even contains a third, triketide-derived module. The constitutions and the absolute configurations of the new metabolites and of altiloxin B were unambiguously determined by a combination of spectroscopic methods and quantum-chemical optical-rotatory dispersion (ORD) and circular dichroism (CD) calculations. A biosynthetic pathway to pestalotiopens A and B is proposed with altiloxin B as one of the suggested precursors. Pestalotiopen A shows moderate antimicrobial activity against Enterococcus faecalis.

Topics: Benzofurans; Fungi; Magnetic Resonance Spectroscopy; Molecular Structure; Plant Leaves; Rhizophoraceae; Sesquiterpenes; Stereoisomerism

Cyclopaldic acid (CA), its six derivatives, and iso-cyclopaldic acid (IsoCA) were assayed for toxicity to cuttings of three species of cypress, as well as to mung bean, oat, and tomato explants. Toxicity to host and non-host plants of CA derivatives having one or both of the aldehyde groups transformed was less than that of CA. Shoot tissues of Cupressus macrocarpa artificially infected by Seiridium cupressi leached electrolytes more than those of C. sempervirens and C. arizonica. CA, IsoCA, and to a lesser extent the monoacetylated, phenylhydrazone and hydrogenated derivatives of CA caused loss of electrolytes from cypress tissues. CA, IsoCA, and monoacetyl CA caused limited callus development of cypress tissues. Diacetylhydrazone CA enhanced the yield of cypress callus tissue. CA derivatives having both aldehyde groups modified induced root formation on cypress cuttings. The antifungal activity showed by CA toward species of Botrytis, Fusarium, and Geotrichum markedly decreased in its derivatives. The inhibitory effect of CA on esterases was exhibited also by IsoCA and the monoacetylated derivative.

Topics: Benzofurans; Electrolytes; Esterases; Fungi; Necrosis; Plants; Structure-Activity Relationship

An antiserum against cyclopaldic acid (CA), a phytotoxic metabolite produced by Seiridium cupressi, the fungal pathogen of a canker disease of cypress, was prepared by immunization of rabbits with a CA-bovine serum albumin conjugate (CA-BSA). Antibodies recognizing CA were purified by affinity chromatography through an immunoadsorbent prepared by conjugating CA to lysine-Sepharose 4B. The specificity of antibodies was assayed against CA and some of its derivatives by competitive indirect enzyme-linked immunoassay. The homologous antigen CA-BSA and CA showed the highest binding activity with antibodies. The derivatives of CA modified in 1 of the 2 aldehyde groups reacted with antibodies to a lesser extent compared with CA-BSA and CA. Isocyclopaldic acid and the tetraacetylderivative of CA, which have more than one modified functional group, showed a further decrease in their reactivity. Other derivatives, which have more substantial structural modifications of the carbon skeleton, did not react. The possible use of these antibodies in studies concerning the involvement of CA in the canker disease of cypress is discussed.

Topics: Animals; Anti-Bacterial Agents; Antibodies; Antibody Formation; Antibody Specificity; Benzofurans; Binding, Competitive; Chromatography, Affinity; Enzyme-Linked Immunosorbent Assay; Female; Mitosporic Fungi; Rabbits; Structure-Activity Relationship

Topics: Benzofurans; Penicillium