Development of an attract-and-infect system to control Rhynchophorus ferrugineus with the entomopathogenic fungus Beauveria bassiana.

Background: A new Beauveria bassiana-based attract and infect device (AID) to control Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) was developed. The virulence and persistence of the fungal formulation used in the AID were evaluated in the laboratory. Semi-field and field trials were carried out to validate the results and establish the potential of this device as a control tool.

Evaluation of lufenuron as a chemosterilant against fruit flies of the genus Anastrepha (Diptera: Tephritidae).

Background: Chemosterilisation with lufenuron bait stations is a recently developed technique that is being implemented for Ceratitis capitata Wiedemann control. The aim of this work was to evaluate the chemosterilising effect of lufenuron against four economically important Latin American fruit flies species: Anastrepha ludens (Loew.), A.

Insecticidal activity of Paraherquamides, including paraherquamide H and paraherquamide I, two new alkaloids isolated from Penicillium cluniae.

Paraherquamide H (1) and paraherquamide I (2), two new compounds of the paraherquamide (PHQ) family, together with the already known paraherquamide A (3), paraherquamide B (4), paraherquamide E (5), VM55596 (N-oxide paraherquamide) (6), paraherquamide VM55597 (7), and five known diketopiperazines (8-12) have been isolated from the culture broth of Penicillium cluniae Quintanilla. The structure of 1 and 2, on the basis of NMR and MS analysis, was established. It is worth noticing that, in both cases, an unusual oxidative substitution in C-16 was found, which had only previously been detected in PHQ 7.

Novel inhibitors of the mitochondrial respiratory chain: oximes and pyrrolines isolated from Penicillium brevicompactum and synthetic analogues.

The capacity of inhibition of the mammalian mitochondrial respiratory chain of brevioxime 5a, a natural insecticide compound isolated from Penicillium brevicompactum culture broth, and another 15 analogue compounds, other oximes 5b and 5c; two diastereomeric pyrrolidines 1c' and 1c' '; five pyrrolines 3c', 3c' ' (diastereomers between them), 3a, 3b, and 6; two oxazines 4c' and 4c' ' (also diastereomers between them); and four pyrrol derivatives 7-10, are analyzed in this paper. Compounds 3b, 3c', 3c' ', 4c', 4c' ', 5b, 5c, 6, and 10 were found to be inhibitors of the integrated electron transfer chain (NADH oxidase activity) in beef heart submitochondrial particles (SMP), establishing that all of them except compound 3b and 6 only affected to complex I of the mitochondrial respiratory chain. The most potent product was 5b, with an IC50 of 0.

Circumdatin H, a new inhibitor of mitochondrial NADH oxidase, from Aspergillus ochraceus.

Circumdatin H (1), a new alkaloid from the culture broth of Aspergillus ochraceus, has been isolated, together with a known circumdatin, circumdatin E (2) and other known compounds: flavacol (3) and stephacidin A (4). The structure of 1 was established on the basis of chemical and spectral evidence. All of these alkaloids showed biological activity as inhibitors of the mammalian mitochondrial respiratory chain.

Screening for metabolites from Penicillium novae-zeelandiae displaying radical-scavenging activity and oxidative mutagenicity: isolation of gentisyl alcohol.

In the search for new natural products with anti-oxidant activity, we have combined the cell-free assay based on the scavenging of the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), with a bioassay that detects oxidative mutagens. This bioassay uses a new Escherichia coli tester strain, IC203, specifically sensitive to oxidative stress due to a deficiency in the OxyR function. OxyR is a redox-sensitive transcriptional activator of genes encoding anti-oxidant enzymes such as catalase and peroxiredoxin alkyl hydroperoxide reductase.

Insecticidal activity of penitrems, including penitrem G, a new member of the family isolated from Penicillium crustosum.

Penitrem G (7), a new indole-diterpenoid compound, has been isolated together with the already known mycotoxins penitrems A-D (1-4) and F (6) from the mycelium of Penicillium crustosum Thom. The structure of penitrem G was established on the basis of spectroscopic data. In addition, paspaline (8), another indole-diterpenoid mycotoxin that has not been previously described in this fungus, was also isolated.