Search

Ambuic acid (AA) is a highly-modified cyclohexenone and known as a promising inhibitor of quorum sensing in methicillinresistant Staphylococcus aureus, and is thus a candidate as an antivirulence drug. This molecule is mainly produced by the species of Pestalotiopsis and, since its discovery twenty years ago, only a restricted amount of AA-derivatives have been described. Despite being a promising subject, methods for the analysis of modified AA-analogues via mass spectrometry remain unexplored. In order to adress this question, the marine fungus Pestalotiopsis sp. 4A11 associated with the ascidian Didemnum perlucidum was grown in a solid rice medium and its crude extract was chemically studied. From this extract, AA and 10-hydroxy ambuic acid (10-HAA) were isolated and identified using NMR spectroscopy with the aim of obtaining model compounds for the MS analysis. These served as reference compounds (seeds) to guide the dereplication of other AA-analogues via LC-MS/MS-based molecular networking. Based on the manual interpretation of the fragmentation pathways of the seeds and related compounds observed in the networks, six AA-derivatives were dereplicated in the extract. Furthermore, three analogues with unprecedented chemical formulas were proposed as putative unprecedented AA-derivatives. The fragmentation annotation proposed represents a fast and feasible method for characterizing AA-derivatives.

Made available in DSpace on 2022-04-29T08:29:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) The genus Absidia is widely used in the biotransformation of different classes of natural products. This study evaluates the ability of the Absidia coerulea 3A9 marine derived strain isolated from the ascidian Distaplia stilyfera to perform biotransformations by conducting assays with (–)-cubebin, as substrate. The experiment was optimized using the experimental design proposed by Plackett–Burman for seven factors and eight experiments, to establish the biotransformation conditions that would allow maximum production of biotransformed dibenzylbutyrolactone (–)-hinokinin. An analytical method based on Reverse-Phase-High Performance Liquid Chromatography (RP-HPLC) was developed to quantify the fungal biotransformation product. The factor that influenced the (–)-hinokinin peak area the most positively was the percentage of seawater (%seawater) given that its %relative standard deviation (%RSD) showed a 32.92% deviation from the real value. Center for Research in Exact and Technological Sciences University of Franca Department of Botany and Ecology Biosciences Institute Federal University of Mato Grosso Center for Natural and Human Sciences Federal University of ABC Department of Drugs and Medicines School of Pharmaceutical Sciences University Estadual Paulista Department of Drugs and Medicines School of Pharmaceutical Sciences University Estadual Paulista CAPES: 001 FAPESP: 2014/19184-7 FAPESP: 2017/14261-1 CAPES: 23038.009588/2013-68 CSF-PVEs 27/2014 CNPq: 302340/2018-1

Actinobacteria is a phylum composed of aerobic, Gram-positive, and filamentous bacteria with a broad spectrum of biological activity, including antioxidant, antitumor, and antibiotic. The crude extract of Streptomyces griseocarneus R132 was fractionated on a C18 silica column and the isolated compound was identified by (1)H and (13)C nuclear magnetic resonance as 3-(phenylprop-2-enoic acid), also known as trans-cinnamic acid. Antimicrobial activity against human pathogens was assayed in vitro (disk-diffusion qualitative test) and in vivo using Galleria mellonella larvae (RT-qPCR). The methanol fractions 132-F30%, 132-F50%, 132-F70%, and 132-F100% inhibited the Escherichia coli (ATCC 25922) and Staphylococcus aureus (MRSA) growth in vitro the most effectively. Compared with the untreated control (60–80% of larvae death), the fractions and isolated trans-cinnamic acid increased the survival rate and modulated the immune system of G. mellonella larvae infected with pathogenic microorganisms. The anti-infection effect of the S. griseocarneus R132 fermentation product led us to sequence its genome, which was assembled and annotated using the Rast and antiSMASH platforms. The assembled genome consisted of 227 scaffolds represented on a linear chromosome of 8.85 Mb and 71.3% of GC. We detected conserved domains typical of enzymes that produce molecules with biological activity, such as polyketides and non-ribosomal and ribosomal peptides, indicating a great potential for obtaining new antibiotics and molecules with biotechnological application. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02942-1.

A central pillar of modern weed control is the discovery of new herbicides which are nontoxic to humans and the environment and which have low application dosage. The natural products found in plants and microorganisms are well suited in this context because they are generally nontoxic and have a wide variety of biological activities. In this work, Diaporthe phaseolorum (Dp), Penicillium simplicissimum (Ps) and Trichoderma spirale (Ts) (methanolic extracts) were evaluated as photosynthesis and plant growth inhibitors in Senna occidentalis and Ipomoea grandifolia. The most significant results were observed for Ts and Dp in S. occidentalis and I. grandifolia, respectively. Ts reduced PI(abs), ET0/CS0, PHI(E0) and PSI0 parameters by 64, 28, 40 and 38%, respectively, indicating a reduction on electron transport efficiency. Additionally, Ts decreased shoot length by 9%, affecting the plant growth. Dp reduced PI(abs), ET0/CS0 and PHI(E0) parameters by 50, 20, 26 and 22%, respectively, revealing the inhibition competency on PSII acceptor site. Furthermore, Dp decreased by 50% the shoot length on germination assay. Thus, the phytotoxic behaviors based on endophytic fungal extracts may serve as a valuable tool in the further development of a bioherbicide since natural products represent an interesting alternative to replace commercial herbicides.

Made available in DSpace on 2019-10-06T16:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Fractionation of extracts from the culture broth of the marine-derived fungus, Paecilomyces sp. 7A22, resulted in the isolation of the harzialactone A (HA), a known compound previously isolated from fungi of marine environments. The chemical structure of HA was determined by spectroscopic analyses. Upon evaluation of HA on antileishmanial assays against Leishmania amazonensis, HA exhibited significant activity against promastigotes forms with IC50 of 5.25 µg mL−1 and moderate activity against intracellular amastigotes with IC50 of 18.18 µg mL−1. This is the first report on the antileishmanial activity of HA, and the effects of HA presented in this work suggest that this class of compounds are suitable for future biological in vitro and in vivo studies for the search of natural products with activity against Leishmania spp. Furthermore, the present results corroborate marine-derived fungi as a promising source of natural products with antiparasitic activity. Faculdade de Ciências Farmacêuticas UNESP–Univ. Estadual Paulista Departamento de Fármacos e Medicamentos Núcleo de Pesquisas em Ciências Exatas e Tecnológicas Universidade de Franca Departamento de Botânica e Ecologia Instituto de Biociências Universidade Federal de Mato Grosso Centro de Ciências Naturais e Humanas Universidade Federal do ABC Faculdade de Ciências Farmacêuticas UNESP–Univ. Estadual Paulista Departamento de Fármacos e Medicamentos

Here, we report the draft genome sequence of the Acinetobacter baumannii strain I43, which is highly resistant to mercury. The Illumina-based sequence analysis revealed a genome of approximately 4,520,353 bp composed of 4,091 coding sequences.

The medicinal plant Vochysia divergens is a colonizing tree species of the Pantanal, a unique and little explored wetland region in Brazil. This species is used in folk medicine as syrups and teas to treat respiratory infections, digestive disorders, asthma, scarring, and skin diseases. The objectives of this study were to evaluate the antioxidant, cytotoxic, and genotoxic potential of the ethanolic extract of Vochysia divergens leaves (VdE), as well as the influence of VdE and its major component (the flavone 3′,5-dimethoxy luteolin-7-O-β-glucopyranoside; 3′5 DL) on MMS-induced genotoxicity. The extract significantly reduced the viability of V79 cells in the colorimetric XTT assay at concentrations ≥ 39 μg/mL. A significant increase in micronucleus frequencies was observed in V79 cell cultures treated with VdE concentrations of 160 and 320 μg/mL. However, animals treated with the tested doses of VdE (500, 1000, and 2000 mg/kg b.w.) exhibited frequencies that did not differ significantly from those of the negative control group, indicating the absence of genotoxicity. The results also showed that VdE was effective in reducing MMS-induced genotoxicity at concentrations of 20, 40, and 80 μg/mL in the in vitro test system and at a dose of 15 mg/kg b.w. in the in vivo test system. Its major component 3′5 DL exerted no protective effect, suggesting that it is not responsible for the effect of the extract. The results of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay showed that VdE was able to scavenge 92.6% of free radicals. In conclusion, the results suggest that the protective effect of VdE may be related, at least in part, to the antioxidant activity of its chemical constituents.

The compounds terrein (1), butyrolactone I (2), and butyrolactone V (3) were isolated from the ethyl acetate extract (EtOAc) of the endophytic fungus Aspergillus terreus—F7 obtained from Hyptis suaveolens (L.) Poit. The extract and the compounds presented schistosomicidal activity against Schistosoma mansoni; at 100 µg/mL for EtOAc extract, 1297.3 µM for compound 1, 235.6 µM for compound 2, and 454.1 µM for compound 3, they killed 100% of the parasites after 72 h of treatment. Compounds 1, 2, and 3 exerted moderate leishmanicidal activity against Leishmania amazonensis (IC50 ranged from 23.7 to 78.6 µM). At 235.6 and 227.0 µM, compounds 2 and 3, respectively, scavenged 95.92 and 95.12% of the DPPH radical (2,2-diphenyl-1-picryl-hydrazyl), respectively. Regarding the cytotoxicity against the breast tumor cell lines MDA-MB-231 and MCF-7, compound 2 gave IC50 of 34.4 and 17.4 µM, respectively, while compound 3 afforded IC50 of 22.2 and 31.9 µM, respectively. At 117.6 µM, compound 2 inhibited the growth of and killed the pathogen Escherichia coli (ATCC 25922). Compounds 1, 2, and 3 displayed low toxicity against the normal line of human lung fibroblasts (GM07492A cells), with IC50 of 15.3 × 103, 3.4 × 103, and 5.8 × 103 µM, respectively. This is the first report on (i) the in vitro schistosomicidal and leishmanicidal activities of the EtOAc extract of A. terreus—F7 and compounds 1, 2, and 3; and (ii) the antitumor activity of compounds 2 and 3 against MDA-MB-231 and MCF-7 cells.

Chemical investigation of the ethyl acetate extract from the endophytic fungus Diaporthe phaseolorum-92C (92C) isolated from the roots of Combretum lanceolatum led to the isolation of 18-des-hydroxy Cytochalasin H (compound 1). The trypanocidal and schistosomicidal activity and cytotoxicity of the extract from 92C were evaluated. The schistosomicidal, leishmanicidal, antimicrobial, and antioxidant actions, as well as the antitumor activity against the breast cancer cells MDA-MB-231 and MCF-7, and the cytotoxicity towards normal human lung fibroblasts GM07492A of compound 1 was tested. The extract from 92C (20 μg/mL) exerted potent trypanocidal activity, reducing 82% of the number of amastigotes and trypomastigotes of Trypanosoma cruzi. Compound 1 at 50 μg/mL killed 50% of Schistosoma mansoni adult worms. Compound 1 reduced the viability of Leishmania amazonenses promastigotes (IC50 = 9.2 μg/mL) and of the cancer cells MDA-MB-231 and MCF-7 (IC50 = 17.5 and 8.88 μg/mL, respectively), presented moderate antioxidant activity, and gave IC50 of 2049.7 ± 39.9 μg/mL for the cytotoxicity towards normal cells GM07492A. This knowledge is highly relevant to the search for new promising compounds for therapeutic purposes.

Vochysia divergens (Vochysiaceae) is considered an invasive species in the wetlands of the Brazilian Pantanal, which hinders the cultivation of agricultural species. In this study, we evaluated the chemical profile by HPLC-DAD (high-performance liquid chromatography-diode array detector) of leaves extracts from V. divergens seedlings inoculated with endophytic fungi isolated from V. divergens roots. These fungi were collected on dry (D) and wet (W) seasons in the Pantanal. The presence of tannin hexahydroxydiphenoyl (HHDP)-galloyl-glucose and flavone 3',5'-dimethoxy-luteolin were predominant in the seedlings inoculated with endophytic fungi W experiments at 100 and 80%, respectively. Likewise, flavone 3',5-dimethoxy-luteolin-7-O-β-glucoside showed a similar representation in the two evaluated periods, compared with 5-methoxy-luteolin, which was detected only in seedlings inoculated with W endophytic fungi. This approach is new to V. divergens, which has no scientific data on its in vitro elicitation, in the search for a better understanding of the ecological relationships of this species.

Vochysia divergens Pohl, known as "Cambara" in Brazil, is an invasive species that is expanding throughout Pantanal in Brazil, to form mono-dominant communities. This expansion is affecting the agricultural areas that support the typical seasonal flood and drought conditions of this biome. This article describes the development and validation of an HPLC-DAD analytical method to quantify 5-methoxyflavones in methanolic extracts of greenhouse-grown V. divergens associated with one of two endophytic fungal species Zopfiella tetraspora (Zt) or Melanconiella elegans (Me) and later subjected to water stress. The developed method gave good validation parameters and was successfully applied to quantify the flavones 3',5-dimethoxy luteolin-7-O-β-glucopyranoside (1), 5-methoxy luteolin (2), and 3',5-dimethoxy luteolin (3) in the target extracts. Inoculation of the plant with Zt decreased the concentration of flavone 1 in the extract by 2.69-fold as compared to the control. Inoculation of the plant with Zt or Me did not significantly alter the contents of flavones 2 and 3 in the extracts as compared to the control. Therefore, the aerial parts of germinated V. divergens plants inoculated with either Zt or Me responded differently in terms of the production of flavones. These results can cast light on the symbiosis between fungal microorganisms and V. divergens, which most likely influences the response of V. divergens to changes in the availability of water in Pantanal.