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1.
BMC Microbiol ; 24(1): 218, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902615

RESUMO

BACKGROUND: Rhizosphere bacterial community and endophytes are now known to influence plant health and response to environmental stress. Very few studies have reported the diversity of endophytic bacterial communities of Vanilla planifolia and their potential roles in promoting plant growth or contributing to aromatic quality. RESULTS: In this study, the composition and diversity of the Vanilla rhizosphere bacterial community were explored by analyzing rhizosphere soil and root tissue samples as well as green pods of three accessions of Vanilla planifolia grown on different types of substrates (compost and leaf litter). In addition, the endophytic bacterial diversity of roots and green pods as well as the evolution of endophytic bacteria after the curing process of vanilla green pods were analyzed based on a metabarcoding approach. The results showed that bacterial species richness and diversity were higher in the compost. The analysis of the soil bacterial composition displayed that Halomonas, Pseudoalteromonas, Enterobacter and Bradyrhizobium were the most abundant genera. Moreover, the results indicated that the soil bacterial community structure was linked to the host plant genotype. Regarding the roots endophytic bacteria composition, the genera Halomonas, Pseudoalteromonas, Bacillus and Carboxydocella genera were present in all samples, independently from the substrate nature. Several genera including Bacillus, Bradyrhizobium, Burkholderia and Halomonas were transmitted internally from the roots to the green pods. The curing process reduced the bacterial richness and bacterial diversity associated with the green pods. Halomonas, Pseudoalteromonas, Bacillus, and Carboxydocella are the dominant genera in the pods after the curing process. CONCLUSIONS: This study provides an overview of changes of the bacterial communities dynamics especially endophytic in the roots and the green pods. It highlighted bacterial genera (Halomonas, Pseudoalteromonas, Bacillus, and Carboxydocella) potentially implicated in the formation of aroma compounds of vanilla beans.


Assuntos
Bactérias , Biodiversidade , Endófitos , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Vanilla , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Raízes de Plantas/microbiologia , Vanilla/microbiologia , RNA Ribossômico 16S/genética , Filogenia , Microbiota/genética , DNA Bacteriano/genética
2.
Curr Microbiol ; 81(9): 298, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107520

RESUMO

Pigments and other secondary metabolites originating from marine microbes have been a promising natural colorants and drugs for multifaceted applications. However, marine actinobacteria producing such natural molecules are least investigated in terms of their taxonomy, chemical diversity and applications in biomedical, textile, and food industries. In this study, sioxanthin pigment-producing Gram-positive actinobacteria, Micromonospora sp. strain SH-82 was isolated from a marine sponge, Scopalina hapalia, and its whole genome was analyzed. Strain SH-82is a prolific producer of diverse chemical molecules as it produced more compounds on A1 medium with different culture conditions. The genome size of SH-82 is 6.24 Mb (6,246,890 bp) carrying 23 identified biosynthetic gene clusters. A total of 5415 CDS, 60 tRNA, 9 rRNA, and 1 tmRNA are identified from SH-82 genome. The GC content (%) of whole genome was 71.6%. Strain SH-82 harbors genes encoding type I, type II, and type III polyketide synthases. Based on the multi-locus sequence analysis and fatty acid methyl ester (FAME) composition, strain SH-82 is confirmed as a novel species. The genetic information of Micromonospora sp. SH-82 has been deposited to NCBI under the BioProject ID PRJNA1087320, with corresponding identifiers in the Sequence Read Archive (SRA) as SAMN40439676 and the Genome accession as CP148049.


Assuntos
Composição de Bases , Genoma Bacteriano , Micromonospora , Filogenia , Poríferos , Micromonospora/genética , Micromonospora/classificação , Micromonospora/isolamento & purificação , Micromonospora/metabolismo , Animais , Poríferos/microbiologia , Família Multigênica , Xantofilas/metabolismo , Ácidos Graxos , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Tipagem de Sequências Multilocus
3.
Mar Drugs ; 22(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38248648

RESUMO

Actinobacteria are known for their production of bioactive specialized metabolites, but they are still under-exploited. This study uses the "One Strain Many Compounds" (OSMAC) method to explore the potential of three preselected marine-derived actinobacteria: Salinispora arenicola (SH-78) and two Micromonospora sp. strains (SH-82 and SH-57). Various parameters, including the duration of the culture and the nature of the growth medium, were modified to assess their impact on the production of specialized metabolites. This approach involved a characterization based on chemical analysis completed with the construction of molecular networks and biological testing to evaluate cytotoxic and antiplasmodial activities. The results indicated that the influence of culture parameters depended on the studied species and also varied in relation with the microbial metabolites targeted. However, common favorable parameters could be observed for all strains such as an increase in the duration of the culture or the use of the A1 medium. For Micromonospora sp. SH-82, the solid A1 medium culture over 21 days favored a greater chemical diversity. A rise in the antiplasmodial activity was observed with this culture duration, with a IC50 twice as low as for the 14-day culture. Micromonospora sp. SH-57 produced more diverse natural products in liquid culture, with approximately 54% of nodes from the molecular network specifically linked to the type of culture support. Enhanced biological activities were also observed with specific sets of parameters. Finally, for Salinispora arenicola SH-78, liquid culture allowed a greater diversity of metabolites, but intensity variations were specifically observed for some metabolites under other conditions. Notably, compounds related to staurosporine were more abundant in solid culture. Consequently, in the range of the chosen parameters, optimal conditions to enhance metabolic diversity and biological activities in these three marine-derived actinobacteria were identified, paving the way for future isolation works.


Assuntos
Actinobacteria , Antimaláricos , Micromonospora , Micromonosporaceae , Antimaláricos/farmacologia , Metabolômica , Bactérias
4.
Molecules ; 28(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36770864

RESUMO

Casearia coriacea Vent., an endemic plant from the Mascarene Islands, was investigated following its antiplasmodial potentialities highlighted during a previous screening. Three clerodane diterpene compounds were isolated and identified as being responsible for the antiplasmodial activity of the leaves of the plant: caseamembrin T (1), corybulosin I (2), and isocaseamembrin E (3), which exhibited half maximal inhibitory concentrations (IC50) of 0.25 to 0.51 µg/mL. These compounds were tested on two other parasites, Leishmania mexicana mexicana and Trypanosoma brucei brucei, to identify possible selectivity in one of them. Although these products possess both antileishmanial and antitrypanosomal properties, they displayed selectivity for the malaria parasite, with a selectivity index between 6 and 12 regarding antitrypanosomal activity and between 25 and 100 regarding antileishmanial activity. These compounds were tested on three cell lines, breast cancer cells MDA-MB-231, pulmonary adenocarcinoma cells A549, and pancreatic carcinoma cells PANC-1, to evaluate their selectivity towards Plasmodium. This has not enabled us to establish selectivity for Plasmodium, but has revealed the promising activity of compounds 1-3 (IC50 < 2 µg/mL), particularly against pancreatic carcinoma cells (IC50 < 1 µg/mL). The toxicity of the main compound, caseamembrin T (1), was then evaluated on zebrafish embryos to extend our cytotoxicity study to normal, non-cancerous cells. This highlighted the non-negligible toxicity of caseamembrin T (1).


Assuntos
Antimaláricos , Casearia , Diterpenos Clerodânicos , Animais , Diterpenos Clerodânicos/farmacologia , Antimaláricos/farmacologia , Peixe-Zebra , Folhas de Planta , Extratos Vegetais/farmacologia , Neoplasias Pancreáticas
5.
Mar Drugs ; 20(10)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36286460

RESUMO

A chemical study of the CH2Cl2-MeOH (1:1) extract from the sponge Ernsta naturalis collected in Rodrigues (Mauritius) based on a molecular networking dereplication strategy highlighted one novel aminopyrimidone alkaloid compound, ernstine A (1), seven new aminoimidazole alkaloid compounds, phorbatopsins D-E (2, 3), calcaridine C (4), naamines H-I (5, 7), naamidines J-K (6, 8), along with the known thymidine (9). Their structures were established by spectroscopic analysis (1D and 2D NMR spectra and HRESIMS data). To improve the investigation of this unstudied calcareous marine sponge, a metabolomic study by molecular networking was conducted. The isolated molecules are distributed in two clusters of interest. Naamine and naamidine derivatives are grouped together with ernstine in the first cluster of twenty-three molecules. Phorbatopsin derivatives and calcaridine C are grouped together in a cluster of twenty-one molecules. Interpretation of the MS/MS spectra of other compounds of these clusters with structural features close to the isolated ones allowed us to propose a structural hypothesis for 16 compounds, 5 known and 11 potentially new.


Assuntos
Alcaloides , Poríferos , Animais , Espectrometria de Massas em Tandem , Estrutura Molecular , Poríferos/química , Alcaloides/química , Timidina
6.
Mar Drugs ; 20(3)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35323485

RESUMO

The biological screening of 44 marine sponge extracts for the research of bioactive molecules, with potential application in the treatment of age-related diseases (cancer and Alzheimer's disease) and skin aging, resulted in the selection of Scopalina hapalia extract for chemical study. As no reports of secondary metabolites of S. hapalia were found in the literature, we undertook this research to further extend current knowledge of Scopalina chemistry. The investigation of this species led to the discovery of four new compounds: two butenolides sinularone J (1) and sinularone K (2), one phospholipid 1-O-octadecyl-2-pentanoyl-sn-glycero-3-phosphocholine (3) and one lysophospholipid 1-O-(3-methoxy-tetradecanoyl)-sn-glycero-3-phosphocholine (4) alongside with known lysophospholipids (5 and 6), alkylglycerols (7-10), epidioxysterols (11 and 12) and diketopiperazines (13 and 14). The structure elucidation of the new metabolites (1-4) was determined by detailed spectroscopic analysis, including 1D and 2D NMR as well as mass spectrometry. Molecular networking was also explored to complement classical investigation and unravel the chemical classes within this species. GNPS analysis provided further information on potential metabolites with additional bioactive natural compounds predicted.


Assuntos
4-Butirolactona/análogos & derivados , Produtos Biológicos , Fosfolipídeos , Piperazinas , Poríferos/química , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , Animais , Baías , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Comores , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fosfolipídeos/química , Fosfolipídeos/isolamento & purificação , Piperazinas/química , Piperazinas/isolamento & purificação , Poríferos/metabolismo
7.
Chem Biodivers ; 19(9): e202200217, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35924460

RESUMO

In this work, phytochemical components, and the antioxidant properties of an aqueous extract obtained from a medicinal plant Hubertia ambavilla, endemic to Reunion Island, were investigated. A total of 37 compounds were detected and identified by high-performance liquid chromatography (UHPLC) using a photodiode-array detector (DAD) coupled with electrospray ionization/mass spectrometry (ESI/MSn ). From calibration curves, the quantity of secondary metabolites in the aqueous extract was calculated. The mean amounts of phenols, flavonoids, and condensed tannins found were 158.38±1.20 mg GAE/g DE, 60.41±1.65 mg AE/g DE and 23.77±1.36 mg CE/g DE, respectively. The in vitro antioxidant properties of the Hubertia ambavilla plant were measured using three methods: DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging and ferric reducing antioxidant power. The results showed that crude aqueous extract of H. ambavilla had effective radical scavenging and reducing power in comparison with standard antioxidant compounds. In conclusion, the crude extract herein presented offers a natural alternative biosource of antioxidants with potential applications in food and health industries.


Assuntos
Asteraceae , Proantocianidinas , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Fenóis/análise , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Polifenóis/análise , Proantocianidinas/análise , Espectrometria de Massas por Ionização por Electrospray
8.
Antonie Van Leeuwenhoek ; 114(1): 95-112, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33369710

RESUMO

Marine sponges are abundant and ecologically important components of coral reefs and have been shown to harbour exceptionally high microbial densities, which can differ substantially among sponge species. However, this dichotomy between high and low microbial abundance (HMA, LMA) sponges is still not fully understood, particularly as concerns the archaeal community. This study aims to fill this gap by analysing (using 454-pyrosequencing of the 16S rRNA gene) how the archaeal community varies among known LMA (Stylissa carteri, and Stylissa massa), known HMA (Hyrtios erectus and Xestospongia testudinaria) and unknown HMA/LMA status sponge species (Ectyoplasia coccinea, Paratetilla bacca and Petrosia aff. spheroida) collected in a remote location in which very few sponge microbial composition studies have been previously performed (Mayotte, Comores archipelago, France) and comparing the results with those reported in four other geographical areas. Based on archaeal community composition, the known LMA sponges formed a distinct cluster together with Paratetilla bacca, Ectyoplasia coccinea and seawater while the known HMA sponge X. testudinaria formed a cluster with Petrosia aff. spheroida. The known HMA sponge H. erectus, in turn, had an intermediate archaeal community between HMA sponges and sediment samples. In addition to the above, we also showed significant compositional congruence between archaeal and bacterial communities sampled from the same sponge individuals. HMA sponges were mainly dominated by members assigned to the genus Nitrosopumilus while LMA sponges were mainly dominated by members assigned to the genus Cenarchaeum. In general, there was no clear difference in richness between HMA and LMA sponges. Evenness, however, was higher in HMA than LMA sponges. Whilst the present study corroborates some of the traits commonly associated with the HMA-LMA dichotomy (higher evenness in Mayotte HMA sponges), this was not consistent across geographical areas showing that more research is needed to fully understand the HMA/LMA dichotomy as concerns Archaea.


Assuntos
Archaea , Poríferos , Animais , Archaea/genética , Biodiversidade , Comores , Humanos , Filogenia , RNA Ribossômico 16S/genética , Água do Mar
9.
Mar Drugs ; 18(7)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635268

RESUMO

Chemical study of the CH2Cl2-MeOH (1:1) extract from the sponge Haliclona sp. collected in Mayotte highlighted three new long-chain highly oxygenated polyacetylenes, osirisynes G-I (1-3) together with the known osirisynes A (4), B (5), and E (6). Their structures were elucidated by 1D and 2D NMR spectra and HRESIMS and MS/MS data. All compounds were evaluated on catalase and sirtuin 1 activation and on CDK7, proteasome, Fyn kinase, tyrosinase, and elastase inhibition. Five compounds (1; 3-6) inhibited proteasome kinase and two compounds (5-6) inhibited CDK7 and Fyn kinase. Osirisyne B (5) was the most active compound with IC50 on FYNB kinase, CDK7 kinase, and proteasome inhibition of 18.44 µM, 9.13 µM, and 0.26 µM, respectively.


Assuntos
Haliclona , Polímero Poliacetilênico/química , Inibidores de Proteassoma/química , Animais , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Polímero Poliacetilênico/farmacologia , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Inibidores de Proteassoma/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
10.
Molecules ; 25(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075135

RESUMO

Dodonea viscosa (L.) Jacq from Reunion Island (Indian Ocean) was investigated for its leaf essential oil composition. The plant was extracted by hydrodistillation and its essential oil analysed by gas chromatography coupled to mass spectrometry. This study revealed that oxygenated nor-diterpenes and diterpenes were one of the major chemical classes (> 50%) mainly consisting of three modified cyclopropylclerodanes containing a bicyclo[5.4.0]undecane ring system: one new furanoid norditerpene, dodovisate C, and two furanoid diterpenes, the known methyl dodovisate A and the new methyl iso-dodovisate A. These three compounds were isolated by liquid chromatography and their structures established on the basis of spectroscopic studies. The absolute configuration of dodovisate C was elucidated through a joint experimental and theoretical (B3LYP/6-311+G(d,p)) electronic circular dichroism study. The relative configurations of methyl dodovisate A and methyl iso-dodovisate A were determined using linear regressions of theoretical chemical shifts versus experimental values with the (B3LYP/6-311+G(d,p)) method.


Assuntos
Diterpenos Clerodânicos/química , Óleos Voláteis/química , Sapindaceae/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Diterpenos Clerodânicos/classificação , Diterpenos Clerodânicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Folhas de Planta/química
11.
J Nat Prod ; 82(5): 1361-1366, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-30943031

RESUMO

An ethyl acetate extract of Psiadia arguta leaves showed in vitro antiplasmodial activity against Plasmodium falciparum with IC50 values of 12.3 ± 2.4 µg/mL (3D7 strain) and 13.5 ± 3.4 µg/mL (W2 strain). Phytochemical investigation led to the isolation and characterization of 16 compounds including four new diterpenoids: labdan-8α-ol-15-yl-(formate) (1), labdan-8α-ol-15-yl-(2-methylbutanoate) (2), labdan-8α-ol-15-yl-(3-methylpentanoate) (3), and labdan-8α-ol-15-yl-(labdanolate) (4). The latter compounds were characterized by spectroscopic methods (1D and 2D NMR, HRMS, and IR). The in vitro antiplasmodial activities of all compounds were evaluated. The known compounds labdan-13( E)-en-8α-ol-15-yl acetate (5), labdan-8α-ol-15-yl acetate (6), 13- epi-sclareol (7), labdan-13( E)-ene-8α,15-diol (8), and (8 R,13 S)-labdane-8α,15-diol (9) exhibited antiplasmodial effects, with IC50 values of 29.1, 33.2, 35.0, 36.6, and 22.2 µM, respectively.


Assuntos
Antimaláricos/farmacologia , Asteraceae/química , Diterpenos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Animais , Diterpenos/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espectrofotometria Infravermelho
12.
Mar Drugs ; 17(3)2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30875899

RESUMO

Chemical study of the CH2Cl2-MeOH (1:1) extract of the sponge Fascaplysinopsis reticulata collected in Mayotte highlighted three new tryptophan derived alkaloids, 6,6'-bis-(debromo)-gelliusine F (1), 6-bromo-8,1'-dihydro-isoplysin A (2) and 5,6-dibromo-8,1'-dihydro-isoplysin A (3), along with the synthetically known 8-oxo-tryptamine (4) and the three known molecules from the same family, tryptamine (5), (E)-6-bromo-2'-demethyl-3'-N-methylaplysinopsin (6) and (Z)-6-bromo-2'-demethyl-3'-N-methylaplysinopsin (7). Their structures were elucidated by 1D and 2D NMR spectra and HRESIMS data. All compounds were evaluated for their antimicrobial and their antiplasmodial activities. Regarding antimicrobial activities, the best compounds are (2) and (3), with minimum inhibitory concentration (MIC) of 0.01 and 1 µg/mL, respectively, towards Vibrio natrigens, and (5), with MIC values of 1 µg/mL towards Vibrio carchariae. In addition the known 8-oxo-tryptamine (4) and the mixture of the (E)-6-bromo-2'-demethyl-3'-N-methylaplysinopsin (6) and (Z)-6-bromo-2'-demethyl-3'-N-methylaplysinopsin (7) showed moderate antiplasmodial activity against Plasmodium falciparum with IC50 values of 8.8 and 8.0 µg/mL, respectively.


Assuntos
Anti-Infecciosos/farmacologia , Antimaláricos/farmacologia , Poríferos/química , Triptaminas/química , Triptaminas/farmacologia , Alcaloides/farmacologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Antimaláricos/química , Antimaláricos/isolamento & purificação , Concentração Inibidora 50 , Biologia Marinha , Plasmodium falciparum/efeitos dos fármacos , Triptaminas/isolamento & purificação , Vibrio/efeitos dos fármacos
13.
J Nat Prod ; 80(6): 1844-1852, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28574260

RESUMO

The extract of a sample of the tunicate Didemnum molle (MAY13-117) collected in Mayotte afforded eight new metabolites, mollecarbamates A-D (1-4) and molleureas B-E (5-8), along with the two known natural products, N,N'-diphenylethyl urea (10) and molleurea A (11). Another sample of D. molle (MAD11-BA065) collected in Baie des Assassins, Madagascar, afforded molledihydroisoquinolone (9). Mollecarbamates 1-4 are a family of compounds that possess repeating o-carboxyphenethylamide units and a carbamate moiety, while the molleureas 5-8 contain tetra- and penta-repeating carboxyphenethylamide units and a urea bridge in different positions. Molledihydroisoquinolone (9) is a cyclic form of o-carboxyphenethylamide. We propose that these unique natural products are most probably produced by an unprecedented biosynthetic pathway that contains a yet unknown chorismate mutase variant. The structures of the compounds were elucidated by interpretation of the data from 1D and 2D NMR, HRESIMS, and MS/MS analyses of the positive ESIMS experiments. Compounds 1-8 were tested against pathogenic bacteria and in a cytoprotective HIV cell based assay but did not show any significant effects in these assays.


Assuntos
Carbamatos/isolamento & purificação , Isoquinolinas/isolamento & purificação , Ureia/análogos & derivados , Ureia/isolamento & purificação , Urocordados/química , Animais , Carbamatos/química , Carbamatos/farmacologia , HIV/efeitos dos fármacos , Humanos , Isoquinolinas/química , Isoquinolinas/farmacologia , Madagáscar , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ureia/química , Ureia/farmacologia
14.
J Nat Prod ; 80(4): 1110-1116, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28207261

RESUMO

The extract of a sample of the sponge Theonella aff. swinhoei collected in Madagascar exhibited promising in vitro antiplasmodial activity. The antiplasmodial activity was ascribed in part to the known metabolite swinholide A. Further investigation of the extract afforded three unusual cyclic peptides, cyclotheonellazoles A-C (1-3), which contain six nonproteinogenic amino acids out of the eight acid units that compose these natural products. Among these acids the most novel were 4-propenoyl-2-tyrosylthiazole and 3-amino-4-methyl-2-oxohexanoic acid. The structure of the compounds was elucidated by interpretation of the 1D and 2D NMR data, HRESIMS, and advanced Merfay's techniques. The new compounds were found to be nanomolar inhibitors of chymotrypsin and sub-nanomolar inhibitors of elastase, but did not present antiplasmodial activity.


Assuntos
Peptídeos Cíclicos/isolamento & purificação , Peptídeos Cíclicos/farmacologia , Poríferos/química , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/farmacologia , Theonella/química , Animais , Quimotripsina/antagonistas & inibidores , Madagáscar , Biologia Marinha , Toxinas Marinhas/química , Toxinas Marinhas/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Elastase Pancreática/antagonistas & inibidores , Peptídeos Cíclicos/química , Inibidores de Proteases/química
15.
J Nat Prod ; 80(5): 1404-1410, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28368118

RESUMO

Chemical study of the CH2Cl2-MeOH (1:1) extract from the sponge Monanchora unguiculata collected in Madagascar highlighted five new compounds, one acyclic guanidine alkaloid, unguiculin A (1) and four pentacyclic alkaloids, ptilomycalins E-H (2-5), along with four known compounds: crambescidin 800 (6) and crambescidin 359 (7), crambescidic acid (8), and fromiamycalin (9). Their structures were elucidated by 1D and 2D NMR spectra and HRESIMS data. All compounds were evaluated for their cytotoxicity against KB cells and their antiplasmodial activity. The new ptilomycalin E (2) and the mixture of the new ptilomycalins G (4) and H (5) showed promising cytotoxicity against KB cells with IC50 values of 0.85 and 0.92 µM, respectively. Ptilomycalin F (3) and fromiamycalin (9) exhibited promising activity against Plasmodium falciparum with IC50 values of 0.23 and 0.24 µM, respectively.


Assuntos
Alcaloides/química , Antimaláricos/farmacologia , Guanidina/análogos & derivados , Guanidinas/química , Plasmodium falciparum/efeitos dos fármacos , Compostos de Espiro/farmacologia , Alcaloides/farmacologia , Alcaloides/toxicidade , Animais , Guanidina/química , Guanidina/farmacologia , Guanidina/toxicidade , Guanidinas/farmacologia , Guanidinas/toxicidade , Humanos , Concentração Inibidora 50 , Células KB , Madagáscar , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Plasmodium falciparum/química , Compostos de Espiro/química , Compostos de Espiro/toxicidade
16.
Chem Biodivers ; 14(6)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28273402

RESUMO

The essential oil from the leaves of Peperomia borbonensis from Réunion Island was obtained by hydrodistillation and characterized using GC-FID, GC/MS and NMR. The main components were myristicin (39.5%) and elemicin (26.6%). The essential oil (EO) of Peperomia borbonensis and its major compounds (myristicin and elemicin), pure or in a mixture, were evaluated for their insecticidal activity against Bactrocera cucurbitae (Diptera: Tephritidae) using a filter paper impregnated bioassay. The concentrations necessary to kill 50% (LC50 ) and 90% (LC90 ) of the flies in three hours were determined. The LC50 value was 0.23 ± 0.009 mg/cm2 and the LC90 value was 0.34 ± 0.015 mg/cm2 for the EO. The median lethal time (LT50 ) was determined to compare the toxicity of EO and the major constituents. The EO was the most potent insecticide (LT50  = 98 ± 2 min), followed by the mixture of myristicin and elemicin (1.4:1) (LT50  = 127 ± 2 min) indicating that the efficiency of the EO is potentiated by minor compounds and emphasizing one of the major assets of EOs against pure molecules.


Assuntos
Inseticidas/isolamento & purificação , Óleos Voláteis/química , Peperomia/química , Folhas de Planta/química , Tephritidae/efeitos dos fármacos , Derivados de Alilbenzenos , Animais , Compostos de Benzil/isolamento & purificação , Compostos de Benzil/toxicidade , Dioxolanos/isolamento & purificação , Dioxolanos/toxicidade , Dípteros/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/farmacologia , Espectroscopia de Ressonância Magnética , Pirogalol/análogos & derivados , Pirogalol/isolamento & purificação , Pirogalol/toxicidade
17.
Mar Drugs ; 14(2)2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26907302

RESUMO

A dichloromethane extract of the soft coral Rhytisma fulvum fulvum collected in Madagascar afforded a novel compound possessing an unprecedented pentacyclic skeleton, bisdioxycalamenene (1), as well as seven known sesquiterpenes. The structures of the compounds were elucidated using 1D and 2D NMR techniques, as well as high-resolution mass spectrometry. The absolute configuration of 1 was determined using X-ray diffraction analysis and anomalous dispersion effects. The structure elucidation and a possible biogenesis of the compound are discussed.


Assuntos
Antozoários/química , Sesquiterpenos/isolamento & purificação , Terpenos/isolamento & purificação , Animais , Madagáscar , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Sesquiterpenos/química , Terpenos/química , Difração de Raios X
18.
Chem Biodivers ; 12(11): 1725-33, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26567950

RESUMO

In our continuing program to isolate new compounds from the Madagascar sponge Biemna laboutei, five new tricyclic guanidine alkaloids, netamines O - S (1-5, resp.), have been identified together with the known compounds netamine E (6) and mirabilin J (7). The structures of all new netamines were assigned on the basis of spectroscopic analyses. Their relative configurations were established by analysis of ROESY data and comparison with literature data. Netamines O, P, and Q, which were isolated in sufficient quantities, were tested for their cytotoxic activities against KB cells and their activities against the malaria parasite Plasmodium falciparum. Netamines O and Q were found to be moderately cytotoxic. Netamines O, P, and Q exhibited antiplasmodial activities with IC50 values of 16.99 ± 4.12, 32.62 ± 3.44, and 8.37 ± 1.35 µM, respectively.


Assuntos
Alcaloides/farmacologia , Antimaláricos/farmacologia , Guanidinas/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Poríferos/química , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Antimaláricos/química , Antimaláricos/isolamento & purificação , Relação Dose-Resposta a Droga , Guanidinas/química , Guanidinas/isolamento & purificação , Madagáscar , Conformação Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade
19.
J Nat Prod ; 77(4): 818-23, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24601655

RESUMO

Chemical examination of the CH2Cl2-MeOH (1:1) extract of the Madagascar sponge Biemna laboutei resulted in the isolation of seven new tricyclic alkaloids, netamines H-N (1-7), along with the known netamine G and mirabilins A, C, and F. Their structures were elucidated by interpretation of 1D and 2D NMR spectra and HRESIMS data. All compounds were evaluated for their cytotoxicity against KB cells and their antiplasmodial activity. Netamine M (6) was found to be cytotoxic, with an IC50 value in the micromolar range, and netamine K (4) exhibited activity against Plasmodium falciparum with an IC50 value of 2.4 µM.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antimaláricos/isolamento & purificação , Antimaláricos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Poríferos/química , Quinazolinas/isolamento & purificação , Quinazolinas/farmacologia , Alcaloides/química , Animais , Antimaláricos/química , Antineoplásicos Fitogênicos/química , Humanos , Concentração Inibidora 50 , Madagáscar , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Quinazolinas/química
20.
Phytochemistry ; 220: 114005, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38309451

RESUMO

Chemical investigation of ethyl acetate bark extracts of Indigofera ammoxylum red and white phenotypes led to the bio-guided isolation of four previously undescribed flavonoids, named (2S,3R)-3',7-dihydroxy-4',6-dimethoxyflavanol (1), (2S,3R)-6-methoxy-7-hydroxyflavanol (2), 2',3',7-trihydroxy-4',6-dimethoxyisoflavone (7) and 2',5' -dimethoxy-4',5,7-trihydroxyisoflavanone (8), along with 14 known compounds (3-6 and 9-18). The previously undescribed structures were characterized based on NMR, HRESIMS, UV and IR data. Published spectroscopic data were used to deduce the structure of the known compounds. Eleven of the 18 isolated metabolites were evaluated for anti-inflammatory activity and cytotoxic activity against human liver carcinoma cells and human colon and colorectal adenocarcinoma cells. All tested compounds showed an anti-inflammatory activity (IC50 NO < 25 µg/mL), and compounds 2 and 3 were more selective than the positive control dexamethasone. Afromorsin (6) showed promising cytotoxic properties against both cancer cell lines (IC50 18.9 and 11.4 µg/mL). Feature-based molecular networking approach applied to bark and leaves extracts of the two phenotypes allowed to detect bioactive analogues, belonging to the families of flavones, isoflavones, flavanones, flavanols and flavonols, and to explore the chemodiversity of the species. The red and white phenotypes have a similar composition, whereas bark and leaves contain specific chemical entities. Finally, this approach highlighted a cluster of potentially bioactive and undescribed metabolites.


Assuntos
Flavanonas , Indigofera , Humanos , Flavonoides/química , Flavonóis , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Estrutura Molecular
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