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• Co-culture was applied to produce structural diversity of natural products. • Perylenequinones were induced by Setophoma sp. in the co-cultures. • Stemphyperylenol was isolated and identified. • Perylenequinone derivatives were detected by dereplication data analysis. • Stemphyperylenol exhibited antifungal effects. • The mode of action of stemphyperylenol was determined. Co-culture strategy can be applied to produce structural diversity of natural products. This approach also enables the understanding of the interaction mechanisms in microbial ecology. The present study aimed at the secondary metabolism diversification of the endophytic fungus Setophoma sp. by co-culturing it with Penicillium brasilianum and Talaromyces wortmannii, species also isolated as endophytes, and with Penicillium digitatum , a phytopathogenic fungus dangerous to Brazilian citriculture. The increase of perylenequinones (stemphyperylenol and derivatives) produced by Setophoma sp. strain was observed in the co-cultures in response to the endophytic P. brasilianum. The induced stemphyperylenol was isolated by combined chromatographic procedures and identified by spectroscopic techniques. Other perylenequinone derivatives were detected by UHPLC-DAD-HRMS based dereplication data analysis. Stemphyperylenol exhibited antifungal effects not only against P. brasilianum , but also against P. digitatum , the main postharvest pathogen of orange fruits, and Aspergillus fumigatus , an important human pathogenic fungus ubiquitous in soil. Preliminary insights concerning the mode of action of stemphyperylenol were determined by evaluating a collection of A. fumigatus mutants. Thus, stemphyperylenol may have the potential for agricultural applications, and it is also promising as a human antifungal compound. Moreover, the co-culture of an endophyte-endophyte system may represent a potential way to achieve the chemical diversity of bioactive molecules. [ABSTRACT FROM AUTHOR]

Abstract: In this work the synthesis and antiparasitical activity of new 1,5-diaryl-3-oxo-1,4-pentadienyl derivatives are described. First, compounds 1a, 1b, 1c and 1d were prepared by acid-catalyzed aldol reaction between 2-butanone and benzaldehyde, anisaldehyde, p-N,N-dimethylaminobenzaldehyde and p-nitrobenzaldehyde. Reacting each of the methyl ketones 1a, 1b, 1c and 1d with the p-substituted benzaldehydes under basic-catalyzed aldol reaction, we further prepared compounds 2a–2p. All twenty compounds were evaluated for antiproliferative activity, particularly for promastigote of Leishmania amazonensis and epimastigote of Trypanosoma cruzi. All compounds showed good activity while nitro compounds 2i and 2k showed inhibition activity at a few μM. [Copyright &y& Elsevier]

The effect of the Bi doping of PbO 2 coatings on the electrochemical degradation of the pesticide tebuconazole (TBC) was investigated. The insertion of 8% Bi (relative to the amount of Pb) in the PbO 2 structure afforded a well-defined texturing in the direction of the (2 0 0) plane to the PbO 2 coatings, as well as, a decrease in the size of the coherent domain of the crystal, an increase in the electrochemical roughness and in the oxidation power of the Bi-doped PbO 2 compared with PbO 2 . Through ultraviolet-visible spectrometry and total organic carbon (TOC) analyses for TCB electrodegradation was possible to chose the current density of 40 mA cm −2 as optimized one, with 68% of TOC removed by the Bi-doped electrode and 56% removed by the PbO 2 electrode. High resolution liquid chromatography coupled with electrospray ionisation high resolution mass spectrometry helped to propose an oxidation pathway for the electrochemical degradation of TBC. Nine electrooxidation products were identified; which were produced by hydroxylation of the TBC phenyl group and its consequent oxidation to a ketone (including both mono- and dihydroxylated products), by dechlorination (two different products), and by multiple oxidative steps with ring opening (two different products). It was possible to conclude that the electrooxidation of TBC using Bi-doped PbO 2 anodes generated products that were less harmful than TBC itself, thus recommending this electrode as an alternative material for wastewater decontamination. [ABSTRACT FROM AUTHOR]

• Determination of tryptoquialanines was validated with accuracy and detectability. • Diffusion of alakaloids between orange layers occurs after 4 Days Post Infection. • Diffusion of alkaloids between infected and health oranges after direct contact. • Absence of the tryptoquialanines on healthy non-infected area. A method was developed and validated for determination of tryptoquialanines A and C in orange samples on epicarp (exterior peel), mesocarp (white peel), and endocarp (fruit juice) based on QuEChERS extraction and LC-MS/MS analysis. The method showed an excellent linearity over a range of 5–400 μg kg−1, with r2 ≥ 0.998. The limits of detection (LOD) and quantification (LOQ) were 5 and 10 µg kg−1, respectively. Recoveries showed values between 57 and 101%, with RSD ≤ 12%. Analysis of infected oranges showed diffusion of the alkaloids between the orange layers after 4 days post infection in concentrations > LOQ. Mycotoxin diffusion to healthy oranges after direct contact with infected oranges for 48 h, showed alkaloid concentrations ≥10 µg kg−1 on epicarp layer. The developed method can be easily applied for quality control in routine analysis of orange fruit due to the high risk that these tremorgenic alkaloids represent to human health. [ABSTRACT FROM AUTHOR]