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Endophytic fungi have been considered a rich source for bioactive secondary metabolites with novel chemical structures. A high diverse group of endophytes, isolated from different medicinal plants, belongs to the genus Diaporthe. In a previously study performed by our group the crude extract of strain LGMF1583 showed considerable antibacterial activity mainly against Gram-negative bacteria. Based on ITS phylogeny analysis, strain LGMF1583 was identified as belonging to Diaporthe genus and may represent a new species. In the present study, we described the new species Diporthe vochysiae based on multilocus phylogeny analysis and morphological characteristics. The species name refers to the host, from which strain LGMF1583 was isolated, the medicinal plant Vochysia divergens. In view of the biotechnological potential of strain LGMF1583, we have also characterized the secondary metabolites produced by D. vochysiae. Chemical assessment of the D. vochysiae LGMF1583 revealed two new carboxamides, vochysiamides A (1) and B (2), in addition to the known metabolite, 2,5-dihydroxybenzyl alcohol (3). In the biological activity analysis, vochysiamide B (2) displayed considerable antibacterial activity against the Gram-negative bacterium Klebsiella pneumoniae (KPC), a producer of carbapenemases, MIC of 80 μg/mL. Carbapenemases are considered a major antimicrobial resistance threat, and infections caused by KPC have been considered a public health problem worldwide, and new compounds with activity against this bacterium are nowadays even more required., (Copyright © 2019. Published by Elsevier B.V.)

Acmella oleracea (jambu), is used as ingredient for food and in folk medicine to relief toothache. Jambu edible flowers are rich in alkylamides, mainly spilanthol, which are responsible to evoke chemesthetic sensations. This study aimed to investigate the local effects promoted by the intraplantar injection of the hexanic fraction (HF) rich in alkylamides from jambu flowers and compare to synthetic isobutylalkyl amide (IBA). Swiss male mice were intraplantarly administrated with HF and IBA (0.1-30 μg/20 μL), and the underlying mechanisms associated to the antinociceptive (0.1 μg) and pronociceptive (30 μg) effects were evaluated in chemical and sensorial tests. HF and IBA at 0.1 μg promoted analgesia in neurogenic and inflammatory phases of formalin test, against glutamate-induced nociception and independent of the activation of endogenous opioidergic system and dependent of TRPV1 modulation, whereas only HF reduced both nociception and mast cell degranulation in hindpaw induced by compound 48/80. However, both potentiated the TRPA1-mediated nociception. In contrast, HF and IBA (30 μg)-evoked nociceptive behaviors were reduced by the activation of opioidergic system, by TRPA1 antagonist and TRP nociceptive fibers desensitization. In addition, 30 μg IBA-evoked nociception by activation of TRPV1, and 30 μg HF by mast cell degranulation. Furthermore, on the contrary of IBA, HF elevated both mechanical and thermal paw threshold. Altogether, these results indicate that alkylamides could elicited dual effects, adding new evidences and mechanisms for these opposite actions in different doses. Although further research is needed, we confirmed that alkylamides displays local analgesic and/or anesthetic effects., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Chromatographic fractionation of a dichloromethane extract from the leaves of Piper scutifolium yielded two new isobutyl amides, scutifoliamide A ( 1) and scutifoliamide B ( 2), together with the known compounds piperolactam C ( 3), piperovatine ( 4), piperlonguminine ( 5), corcovadine ( 6), isopiperlonguminine ( 7), and isocorcovadine ( 8). From the dichloromethane extract from the leaves of P. hoffmannseggianum two new isobutyl amides, hoffmannseggiamide A ( 9) and hoffmannseggiamide B ( 10), were obtained together with the known compounds isopiperlonguminine ( 7) and isocorcovadine ( 8), sitosterol, and stigmasterol. The structures of the new compounds were established on the basis of spectroscopic data analysis. The inhibitory activity of compounds 1-10 against the growth of the fungi Cladosporium sphaerospermum and C. cladosporioides was determined by bioautography.