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1.
Nat Prod Rep ; 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38411238

ABSTRACT

Covering: September 1964 to June 2023Bacteria and fungi living in symbiosis with insects have been studied over the last sixty years and found to be important sources of bioactive natural products. Not only classic producers of secondary metabolites such as Streptomyces and other members of the phylum Actinobacteria but also numerous bacteria from the phyla Proteobacteria and Firmicutes and an impressive array of fungi (usually pathogenic) serve as the source of a structurally diverse number of small molecules with important biological activities including antimicrobial, cytotoxic, antiparasitic and specific enzyme inhibitors. The insect niche is often the exclusive provider of microbes producing unique types of biologically active compounds such as gerumycins, pederin, dinactin, and formicamycins. However, numerous insects still have not been described taxonomically, and in most cases, the study of their microbiota is completely unexplored. In this review, we present a comprehensive survey of 553 natural products produced by microorganisms isolated from insects by collating and classifying all the data according to the type of compound (rather than the insect or microbial source). The analysis of the correlations among the metadata related to insects, microbial partners, and their produced compounds provides valuable insights into the intricate dynamics between insects and their symbionts as well as the impact of their metabolites on these relationships. Herein, we focus on the chemical structure, biosynthesis, and biological activities of the most relevant compounds.

2.
Nat Commun ; 15(1): 33, 2024 01 02.
Article in English | MEDLINE | ID: mdl-38167253

ABSTRACT

Aspergillus fumigatus is a saprophytic fungus that can cause a variety of human diseases known as aspergillosis. Mycotoxin gliotoxin (GT) production is important for its virulence and must be tightly regulated to avoid excess production and toxicity to the fungus. GT self-protection by GliT oxidoreductase and GtmA methyltransferase activities is related to the subcellular localization of these enzymes and how GT can be sequestered from the cytoplasm to avoid increased cell damage. Here, we show that GliT:GFP and GtmA:GFP are localized in the cytoplasm and in vacuoles during GT production. The Mitogen-Activated Protein kinase MpkA is essential for GT production and self-protection, interacts physically with GliT and GtmA and it is necessary for their regulation and subsequent presence in the vacuoles. The sensor histidine kinase SlnASln1 is important for modulation of MpkA phosphorylation. Our work emphasizes the importance of MpkA and compartmentalization of cellular events for GT production and self-defense.


Subject(s)
Aspergillosis , Gliotoxin , Humans , Aspergillus fumigatus/metabolism , Gliotoxin/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Mitogen-Activated Protein Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , Aspergillosis/microbiology
3.
Front Microbiol ; 14: 1221724, 2023.
Article in English | MEDLINE | ID: mdl-37637114

ABSTRACT

Symbiotic interactions between microorganisms and social insects have been described as crucial for the maintenance of these multitrophic systems, as observed for the stingless bee Scaptotrigona depilis and the yeast Zygosaccharomyces sp. SDBC30G1. The larvae of S. depilis ingest fungal filaments of Zygosaccharomyces sp. SDBC30G1 to obtain ergosterol, which is the precursor for the biosynthesis of ecdysteroids that modulate insect metamorphosis. In this work, we find a similar insect-microbe interaction in other species of stingless bees. We analyzed brood cell samples from 19 species of stingless bees collected in Brazil. The osmophilic yeast Zygosaccharomyces spp. was isolated from eight bee species, namely Scaptotrigona bipunctata, S. postica, S. tubiba, Tetragona clavipes, Melipona quadrifasciata, M. fasciculata, M. bicolor, and Partamona helleri. These yeasts form pseudohyphae and also accumulate ergosterol in lipid droplets, similar to the pattern observed for S. depilis. The phylogenetic analyses including various Zygosaccharomyces revealed that strains isolated from the brood cells formed a branch separated from the previously described Zygosaccharomyces species, suggesting that they are new species of this genus and reinforcing the symbiotic interaction with the host insects.

4.
Res Sq ; 2023 May 31.
Article in English | MEDLINE | ID: mdl-37398048

ABSTRACT

Aspergillus fumigatus is a saprophytic fungus that can cause a variety of human diseases known as aspergillosis. Mycotoxin gliotoxin (GT) production is important for its virulence and must be tightly regulated to avoid excess production and toxicity to the fungus. GT self-protection by GliT oxidoreductase and GtmA methyltransferase activities is related to the subcellular localization of these enzymes and how GT can be sequestered from the cytoplasm to avoid increased cell damage. Here, we show that GliT:GFP and GtmA:GFP are localized in the cytoplasm and in vacuoles during GT production. Peroxisomes are also required for proper GT production and self-defense. The Mitogen-Activated Protein (MAP) kinase MpkA is essential for GT production and self-protection, interacts physically with GliT and GtmA and it is necessary for their regulation and subsequent presence in the vacuoles. Our work emphasizes the importance of dynamic compartmentalization of cellular events for GT production and self-defense.

5.
Biota Neotrop. (Online, Ed. ingl.) ; 22(spe): e20221345, 2022. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1394011

ABSTRACT

Abstract The present review aims the discussion of the impact of the bioprospection initiative developed by the projects associated to BIOprospecTA, a subprogram of the program BIOTA, supported by FAPESP. This review brings a summary of the main results produced by the projects investigating natural products (NPs) from non-plants organisms, as examples of the success of this initiative, focusing on the progresses achieved by the projects related to NPs from macroalgae, marine invertebrates, arthropods and associated microorganisms. Macroalgae are one of the most studied groups in Brazil with the isolation of many bioactive compounds including lipids, carotenoids, phycocolloids, lectins, mycosporine-like amino acids and halogenated compounds. Marine invertebrates and associated microorganisms have been more systematically studied in the last thirty years, revealing unique compounds, with potent biological activities. The venoms of Hymenopteran insects were also extensively studied, resulting in the identification of hundreds of peptides, which were used to create a chemical library that contributed for the identification of leader models for the development of antifungal, antiparasitic, and anticancer compounds. The built knowledge of Hymenopteran venoms permitted the development of an equine hyperimmune serum anti honeybee venom. Amongst the microorganisms associated with insects the bioprospecting strategy was to understand the molecular basis of intra- and interspecies interactions (Chemical Ecology), translating this knowledge to possible biotechnological applications. The results discussed here reinforce the importance of BIOprospecTA program on the development of research with highly innovative potential in Brazil.


Resumo A presente revisão discute o impacto das iniciativas de bioprospecção desenvolvidas pelos projetos associados ao BIOprospecTA, subprograma do programa BIOTA, apoiado pela FAPESP. Esta revisão traz um resumo dos principais resultados produzidos pelos projetos de investigação de produtos naturais (PNs) de organismos não vegetais, como exemplos do sucesso desta iniciativa, com foco nos avanços alcançados pelos projetos relacionados a PNs de macroalgas, invertebrados marinhos, artrópodes e microrganismos associados. As macroalgas são um dos grupos mais estudados no Brasil com o isolamento de muitas substâncias bioativas, incluindo lipídios, carotenóides, ficocolóides, lectinas, aminoácidos do tipo micosporina e substâncias halogenadas. Invertebrados marinhos e microrganismos associados têm sido estudados de forma mais sistemática nos últimos trinta anos, revelando substâncias únicas, com potentes atividades biológicas. Os venenos de insetos himenópteros também foram amplamente estudados, resultando na identificação de centenas de peptídeos, que foram utilizados para criar uma biblioteca química que contribuiu para a identificação de modelos para o desenvolvimento de substâncias antifúngicas, antiparasitárias e anticancerígenas. O conhecimento construído dos venenos de himenópteros permitiu o desenvolvimento de um soro equino anti-peçonha de abelha. Dentre os microrganismos associados a insetos, a estratégia de bioprospecção foi compreender as bases moleculares das interações intra e interespécies (Ecologia Química), traduzindo esse conhecimento para possíveis aplicações biotecnológicas. Os resultados aqui discutidos reforçam a importância do programa BIOprospecTA no desenvolvimento de pesquisas com alto potencial inovador no Brasil.

6.
Curr Opin Insect Sci ; 44: 41-47, 2021 04.
Article in English | MEDLINE | ID: mdl-33271364

ABSTRACT

Stingless bees (Meliponini) are a monophyletic group of eusocial insects inhabiting tropical and subtropical regions. These insects represent the most abundant and diversified group of corbiculate bees. Meliponini mostly rely on fermentation by symbiont microbes to preserve honey and transform pollen in stored food. Bee nests harbor diverse microbiota that includes bacteria, yeasts, filamentous fungi, and viruses. These microorganisms may interact with the bees through symbiotic relationships, or they may act as food for the insects, or produce biomolecules that aid in the biotransformation of bee products, such as honey and bee bread. Certain microbial species can also produce antimicrobial compounds that inhibit opportunistic bee pathogens.


Subject(s)
Bees/microbiology , Microbiota , Nesting Behavior , Symbiosis , Animals , Bacteria , Viruses , Yeasts/physiology
7.
J Nat Prod ; 83(3): 610-616, 2020 03 27.
Article in English | MEDLINE | ID: mdl-32073851

ABSTRACT

Social insects establish complex interactions with microorganisms, some of which play defensive roles in colony protection. The important role of pollinators such as the stingless bee Melipona scutellaris in nature encouraged us to pursue efforts to study its associated microbiota. Here we describe the discovery of two novel cyclic hexadepsipeptides, meliponamycin A (1) and meliponamycin B (2), from Streptomyces sp. ICBG1318 isolated from M. scutellaris nurse bees. Their structures were established by interpretation of NMR and MS data, and the absolute configuration of the constituent amino acids was determined by the advanced Marfey's method. Compounds 1 and 2 showed strong activity against the entomopathogen Paenibacillus larvae and human pathogens Staphylococcus aureus and Leishmania infantum.


Subject(s)
Anti-Infective Agents/pharmacology , Bees/microbiology , Streptomyces/chemistry , Animals , Leishmania infantum/drug effects , Microbiota , Molecular Structure , Paenibacillus larvae/drug effects , Staphylococcus aureus/drug effects
8.
Inflamm Res ; 69(1): 115-130, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31786615

ABSTRACT

OBJECTIVE: To examine whether free (3-PD-5free) and/or liposomal (3-PD-5lipo) 6,7-dihydroxy-3-[3',4'-methylenedioxyphenyl]-coumarin (3-PD-5) (1) modulate the effector functions of neutrophils from patients with rheumatoid arthritis under remission (i-RA) and with active disease (a-RA), in vitro; and (2) exert anti-inflammatory effect in a rat model of zymosan-induced acute joint inflammation. METHODS AND RESULTS: Incorporation of 3-PD-5 into unilamellar liposomes of soya phosphatidylcholine and cholesterol was efficient (57.5 ± 7.9%) and yielded vesicles with low diameter (133.7 ± 18.4 nm), polydispersity index (0.39 ± 0.06), and zeta potential (- 1.22 ± 0.34 mV). 3-PD-5free (1 µM) and 3-PD-5lipo (3 µM) equally suppressed elastase release and reactive oxygen species generation in neutrophils from healthy subjects and i-RA and a-RA patients, stimulated with immune complexes. 3-PD-5free (20 µM) suppressed the release of neutrophil extracellular traps and chemotaxis in vitro, without clear signs of cytotoxicity. 3-PD-5lipo (1.5 mg/kg, i.p.) diminished joint edema and synovial infiltration of total leukocytes and neutrophils, without changing the synovial levels of TNF-α, IL-1ß, and IL-6. CONCLUSION: Altogether, the results reported herein indicate that 3-PD-5 is a promising modulator of the early stages of acute joint inflammation that can help to diminish not only excessive neutrophil infiltration in the synovia but also neutrophil activation and its outcomes in RA patients.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/drug therapy , Coumarins/administration & dosage , Acute Disease , Adult , Aged , Animals , Arthritis, Rheumatoid/immunology , Extracellular Traps/drug effects , Female , Humans , Immunomodulation , Liposomes , Male , Middle Aged , Neutrophil Infiltration/drug effects , Neutrophils/drug effects , Neutrophils/immunology , Neutrophils/physiology , Rats, Wistar , Young Adult
9.
PLoS One ; 14(7): e0219696, 2019.
Article in English | MEDLINE | ID: mdl-31344052

ABSTRACT

The Brazilian stingless bee Scaptotrigona depilis requires the brood cells-associated fungus Zygosaccharomyces sp. as steroid source for metamorphosis. Besides the presence of Zygosaccharomyces sp., other fungi inhabit S. depilis brood cells, but their biological functions are unknown. Here we show that Candida sp. and Monascus ruber, isolated from cerumen of S. depilis brood provisions, interact with Zygosaccharomyces sp. and modulate its growth. Candida sp. produces volatile organic compounds (VOCs) that stimulate Zygosacchromyces sp. development. Monascus ruber inhibits Zygosacchromyces sp. growth by producing lovastatin, which blocks steroid biosynthesis. We also observed that in co-cultures M. ruber inhibits Candida sp. through the production of monascin. The modulation of Zygosaccharomyces sp. growth by brood cell-associated fungi suggests their involvement in S. depilis larval development. This tripartite fungal community opens new perspectives in the research of microbial interactions with bees.


Subject(s)
Bees/growth & development , Bees/microbiology , Fungi/growth & development , Metamorphosis, Biological , Microbiota , Symbiosis/physiology , Animals , Secondary Metabolism
10.
J Chem Ecol ; 44(12): 1158-1169, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30350228

ABSTRACT

Social insects are frequently observed in symbiotic association with bacteria that produce antimicrobial natural products as a defense mechanism. There is a lack of studies on the microbiota associated with stingless bees and their antimicrobial compounds. To the best of our knowledge, this study is the first to report the isolation of Paenibacillus polymyxa ALLI-03-01 from the larval food of the stingless bee Melipona scutellaris. The bacterial strain was cultured under different conditions and produced (L)-(-)-3-phenyllactic acid and fusaricidins, which were active against entomopathogenic fungi and Paenibacillus larvae. Our results indicate that such natural products could be related to colony protection, suggesting a defense symbiosis between P. polymyxa ALLI-03-01 and Melipona scutellaris.


Subject(s)
Anti-Infective Agents/pharmacology , Bees/microbiology , Fungi/drug effects , Paenibacillus polymyxa/metabolism , Animals , Anti-Infective Agents/analysis , Anti-Infective Agents/metabolism , Bees/growth & development , Depsipeptides/analysis , Depsipeptides/metabolism , Depsipeptides/pharmacology , Disk Diffusion Antimicrobial Tests , Lactates/analysis , Lactates/metabolism , Lactates/pharmacology , Larva/microbiology , Microbiota , Paenibacillus polymyxa/classification , Paenibacillus polymyxa/genetics , Paenibacillus polymyxa/isolation & purification , Phylogeny , RNA, Ribosomal, 16S/chemistry , RNA, Ribosomal, 16S/classification , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
11.
Chem Soc Rev ; 47(5): 1652-1704, 2018 Mar 05.
Article in English | MEDLINE | ID: mdl-29218336

ABSTRACT

Microorganisms are found everywhere, and they are closely associated with plants. Because the establishment of any plant-microbe association involves chemical communication, understanding crosstalk processes is fundamental to defining the type of relationship. Although several metabolites from plants and microbes have been fully characterized, their roles in the chemical interplay between these partners are not well understood in most cases, and they require further investigation. In this review, we describe different plant-microbe associations from colonization to microbial establishment processes in plants along with future prospects, including agricultural benefits.


Subject(s)
Microbiota , Plants/chemistry , Plants/microbiology , Signal Transduction
12.
Rev. bras. farmacogn ; 27(4): 529-532, July-Aug. 2017. tab, graf
Article in English | LILACS | ID: biblio-1042252

ABSTRACT

ABSTRACT Aspergillus spp. cause economic impacts due to aflatoxins production. Although the toxicity of aflatoxins is already known, little information about their ecological roles is available. Here we investigated the compounds produced by Aspergillus nomius ASR3 directly from a dead leaf-cutter queen ant Atta sexdens rubropilosa and the fungal axenic culture. Chemical analyses were carried out by high-resolution mass spectrometry and tandem mass spectrometry techniques. Aflatoxins B1 and G1 were detected in both the axenic culture and in the dead leaf-cutter queen ant. The presence of these mycotoxins in the dead leaf-cutter queen ant suggests that these compounds can be related to the insect pathogenicity of A. nomius against A. sexdens rubropilosa.

13.
J Nat Prod ; 80(5): 1302-1309, 2017 05 26.
Article in English | MEDLINE | ID: mdl-28375005

ABSTRACT

During an investigation of the chemistry of the endophytic actinobacterium Streptomyces albospinus RLe7, which was isolated from the roots of the Brazilian medicinal plant Lychnophora ericoides, three new natural products, (2R*,4S*)-2-((1'S*)-hydroxy-4'-methylpentyl)-4-(hydroxymethyl)butanolide (1), (3R*,4S*,5R*,6S*)-tetrahydro-4-hydroxy-3,5,6-trimethyl-2-pyranone (2), and 1-O-(phenylacetyl)glycerol (3), together with known secondary metabolites (S)-4-benzyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (4), (S)-4-isobutyl-3-oxo-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbaldehyde (5), and the diketopiperazines cyclo(l-Tyr-l-Pro) (6) and cyclo(l-Val-l-Pro) (7), were isolated. The role of isolated natural products in the interaction between S. albospinus RLe7 and the fungus Coniochaeta sp. FLe4, an endophyte from the same plant, was investigated. None of these isolated actinobacterial compounds were able to inhibit the fungus or induce the fungal red pigmentation observed when both endophytes interact. Further investigation using mass spectrometry approaches enabled identifying the well-known antifungal compound amphotericin B (9) as a microbial metabolite of S. albospinus RLe7. Finally, compound 9 was demonstrated as at least one of the agents responsible for both the antifungal activity and induction of red-pigmented fungal phenotype.


Subject(s)
Amphotericin B/isolation & purification , Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Ascomycota/drug effects , Asteraceae/drug effects , Biological Products/metabolism , Diketopiperazines/pharmacology , Endophytes/chemistry , Plant Roots/microbiology , Streptomyces/chemistry , Amphotericin B/chemistry , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Biological Products/chemistry , Brazil , Diketopiperazines/chemistry , Molecular Structure , Plant Roots/chemistry
14.
Chem Biodivers ; 13(6): 727-36, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27128202

ABSTRACT

Endophytic actinobacteria from the Brazilian medicinal plant Lychnophora ericoides were isolated for the first time, and the biological potential of their secondary metabolites was evaluated. A phylogenic analysis of isolated actinobacteria was accomplished with 16S rRNA gene sequencing, and the predominance of the genus Streptomyces was observed. All strains were cultured on solid rice medium, and ethanol extracts were evaluated with antimicrobial and cytotoxic assays against cancer cell lines. As a result, 92% of the extracts showed a high or moderate activity against at least one pathogenic microbial strain or cancer cell line. Based on the biological and chemical analyses of crude extracts, three endophytic strains were selected for further investigation of their chemical profiles. Sixteen compounds were isolated, and 3-hydroxy-4-methoxybenzamide (9) and 2,3-dihydro-2,2-dimethyl-4(1H)-quinazolinone (15) are reported as natural products for the first time in this study. The biological activity of the pure compounds was also assessed. Compound 15 displayed potent cytotoxic activity against all four tested cancer cell lines. Nocardamine (2) was only moderately active against two cancer cell lines but showed strong activity against Trypanosoma cruzi. Our results show that endophytic actinobacteria from L. ericoides are a promising source of bioactive compounds.


Subject(s)
Actinobacteria/isolation & purification , Actinobacteria/metabolism , Antineoplastic Agents, Phytogenic/pharmacology , Antiprotozoal Agents/pharmacology , Asteraceae/microbiology , Biological Products/pharmacology , Secondary Metabolism , Actinobacteria/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Biological Products/chemistry , Biological Products/isolation & purification , Brazil , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Parasitic Sensitivity Tests , Plants, Medicinal/microbiology , Structure-Activity Relationship , Trypanosoma cruzi/drug effects
15.
Electrophoresis ; 35(19): 2877-84, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24981999

ABSTRACT

The present work describes, for the first time, the simultaneous separation of oxcarbazepine (OXC) and its active metabolite 10-hydroxy-10,11-dihydrocarbamazepine (licarbazepine, Lic) by chiral CE. The developed method was employed to monitor the enantioselective biotransformation of OXC into its active metabolite by fungi. The electrophoretic separations were performed using 10 mmol/L of a Tris-phosphate buffer solution (pH 2.5) containing 1% w/v of ß-CD phosphate sodium salt (P-ß-CD) as running electrolyte, -20 kV of applied voltage and a 15°C capillary temperature. The method was linear over the concentration range of 1000-30 000 ng/mL for OXC and 75-900 ng/mL for each Lic enantiomer (r ≥ 0.9952). Within-day precision and accuracy evaluated by RSD and relative errors, respectively, were lower than 15% for all analytes. The validated method was used to evaluate the enantioselective biotransformation of OXC, mediated by fungi, into its active metabolite Lic. This study showed that the fungi Glomerella cingulata (VA1) and Beuveria bassiana were able to enantioselectively metabolize the OXC into Lic after 360 h of incubation. Biotransformation by the fungus Beuveria bassiana showed 79% enantiomeric excess for (S)-(+)-Lic, while VA1 gave an enantiomeric excess of 100% for (S)-(+)-Lic. This study opens a new route to the drug (S)-(+)-licarbazepine.


Subject(s)
Carbamazepine/analogs & derivatives , Dibenzazepines , Electrophoresis, Capillary/methods , Phyllachorales/metabolism , Biotransformation , Carbamazepine/analysis , Carbamazepine/chemistry , Carbamazepine/metabolism , Dibenzazepines/analysis , Dibenzazepines/chemistry , Dibenzazepines/metabolism , Linear Models , Oxcarbazepine , Reproducibility of Results , Sensitivity and Specificity , Stereoisomerism
16.
J Pharm Biomed Anal ; 95: 113-20, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24667565

ABSTRACT

Because piplartine (PPT) has demonstrated biological activities, such as cytotoxic, anxiolytic, antidepressant, antifungal and antiplatelet activities, this molecule is a relevant drug candidate. The metabolic fate of drug candidates is an essential requirement in assessing their safety and efficacy. Based on this requirement, the biotransformation of PPT by cytochrome P450 enzymes (CYP) was investigated for the first time. To determine the in vitro enzymatic kinetic parameters, an HPLC method was developed and validated to quantify PPT. All samples were separated on a reversed-phase C18 column using a mobile phase of acetonitrile:water (40:60, v/v). The method exhibited a linear range of 2.4-157.7 µmol/L, with the following calibration curve: y=0.0934 (±0.0010)x+0.0027, r=0.9975. The lower limit of quantitation was verified to be 2.4 µmol/L, with an RSD below 7%. The precision and accuracy were assessed for both within-day and between-day determinations; neither relative standard (RSD%) deviations nor relative errors (RER) exceeded a value of 15%. The mean absolute recovery was 85%, with an RSD value below 6%. The enzymatic kinetic parameters revealed a sigmoidal profile, with V(max)=4.7±0.3 µmol/mg mL⁻¹/min, h=2.5±0.4, S50=44.7±0.3 µmol/L and CL(max)=0.054 µL/min/mg protein, indicating cooperativity behavior. Employing a mammalian model, PPT metabolism yielded two unreported monohydroxylated products (m/z 334). The identification and structural elucidation of the metabolites were performed by comparing their mass spectra with those spectra of the parent drug. For the first time, the in vitro metabolism studies employing microsomes were demonstrated to be a suitable tool for data regarding enzymatic kinetics and for the metabolites formed in the PPT mammalian metabolism.


Subject(s)
Microsomes, Liver/metabolism , Piperidones/metabolism , Animals , Chromatography, High Pressure Liquid , Drug Stability , Male , Rats , Rats, Wistar , Spectrometry, Mass, Electrospray Ionization , Tandem Mass Spectrometry
17.
Phytochemistry ; 96: 92-100, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24135634

ABSTRACT

Biotransformation of chemicals by microorganisms can be effective in increasing chemical diversity. Some fungi have been described to be useful for the biotransformation of sesquiterpene lactones. Nevertheless, in most cases, only minor or simple transformations of functional groups have been observed. Budlein A is a sesquiterpene lactone found in high amounts in American sunflower-like species of the genus Viguiera (Asteraceae). It shows important biological effects like in vitro and in vivo anti-inflammatory activity, as well as cytotoxicity against cancer cell lines. With the aim to obtain potentially bioactive derivatives of budlein A and taking into account that obtaining semi-synthetic analogues is a very complex task, the capability of soil fungi to promote biotransformation was investigated. In this work, the biotransformation of budlein A by the soil fungi Aspergillus terreus and A. niger affording three unusual sesquiterpenoid derivatives with carbon skeletons is reported. The chemical structures of the compounds were elucidated by 1D and 2D NMR spectrometry and HR-ESI-MS. The stereochemistry and molecular conformation of one derivative was assessed by molecular modeling techniques. The fungal metabolites displayed a reduced cytotoxicity against HL-60 cells when compared to the original natural product. The results show the versatility of microbial-catalyzed biotransformations leading to unusual derivatives.


Subject(s)
Anti-Inflammatory Agents/metabolism , Aspergillus/metabolism , Lactones/metabolism , Sesquiterpenes/metabolism , Aspergillus/growth & development , Asteraceae/chemistry , Asteraceae/metabolism , Asteraceae/microbiology , Biotransformation , Early Detection of Cancer , HL-60 Cells , Humans , Lactones/chemistry , Models, Molecular , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Sesquiterpenes/chemistry , Soil Microbiology , Stereoisomerism
18.
Talanta ; 116: 743-52, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24148469

ABSTRACT

We developed a capillary electrophoresis (CE) and dispersive liquid-liquid microextraction (DLLME) method to stereoselectively analyze hydroxyzine (HZ) and cetirizine (CTZ) in liquid culture media. The CE analyses were performed on an uncoated fused-silica capillary; 50mmolL(-1) sodium borate buffer (pH 9.0) containing 0.8% (w/v) S-ß-CD was used as the background electrolyte. The applied voltage and temperature were +6 kV and 15 °C, respectively, and the UV detector was set to 214 nm. Chloroform (300 µL) and ethanol (400 µL) were used as the extraction and disperser solvents, respectively, for the DLLME. Following the formation of a cloudy solution, the samples were subjected to vortex agitation at 2000 rpm for 30s and to centrifugation at 3000 rpm for 5 min. The recoveries ranged from 87.4 to 91.7%. The method was linear over a concentration range of 250-12,500 ng mL(-1) for each HZ enantiomer (r>0.998) and 125-6250 ng mL(-1) for each CTZ enantiomer (r>0.998). The limits of quantification were 125 and 250 ng mL(-1) for CTZ and HZ, respectively. Among the six fungi studied, three species were able to convert HZ to CTZ enantioselectively, particularly the fungus Cunninghamella elegans ATCC 10028B, which converted 19% of (S)-HZ to (S)-CTZ with 65% enantiomeric excess.


Subject(s)
Anti-Allergic Agents/isolation & purification , Cetirizine/isolation & purification , Cunninghamella/metabolism , Hydroxyzine/isolation & purification , Liquid Phase Microextraction/methods , Anti-Allergic Agents/chemistry , Anti-Allergic Agents/metabolism , Biotransformation , Cetirizine/chemistry , Cetirizine/metabolism , Chloroform/chemistry , Culture Media , Electrophoresis, Capillary , Ethanol/chemistry , Hydrogen-Ion Concentration , Hydroxyzine/chemistry , Hydroxyzine/metabolism , Solvents/chemistry , Stereoisomerism
19.
J Pharm Biomed Anal ; 72: 240-4, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22995290

ABSTRACT

The lignan (-)-grandisin has shown important pharmacological activities, such as citotoxicity and antiangiogenic, antibacterial and trypanocidal activities. So, it has been considered as a potential drug candidate. In the early drug development process, drug metabolism is one of the main parameters that should be evaluated; therefore, the biotransformation of this lignan by rat liver microsomes was investigated for the first time. In order to perform the biotransformation study and to determine the kinetic parameters, a simple, sensitive and selective HPLC method was developed and fully validated. After method validation, the biotransformation study was accomplished and the kinetic parameters were determined. The biotransformation study obeyed the Michaelis-Menten kinetics. The V(max) and K(m) were 1.46 ± 0.034 µmol/mg protein/h and 8.99 ± 0.488 µM, respectively. In addition, the formation of dihydro-grandisin, characterized by GC-MS, by mammalian systems indicated the involvement of a CYP450 enzyme type.


Subject(s)
Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Furans/chemistry , Furans/metabolism , Lignans/chemistry , Lignans/metabolism , Animals , Antineoplastic Agents/pharmacokinetics , Biotransformation , Chromatography, High Pressure Liquid/methods , Furans/pharmacokinetics , Kinetics , Lignans/pharmacokinetics , Male , Microsomes, Liver/metabolism , Rats , Rats, Wistar
20.
J Chromatogr Sci ; 51(5): 460-7, 2013.
Article in English | MEDLINE | ID: mdl-23051063

ABSTRACT

A high-performance liquid chromatography (HPLC) method is presented for the simultaneous determination of midodrine and desglymidodrine (DMAE) in Czapek-Dox culture medium, to be used in biotransformation studies by fungi. The HPLC analysis was conducted using a Lichrospher 100 RP18 column, acetonitrile-40 mmol/L formic acid solution (60:40, v/v) as mobile phase, and ultraviolet detection at 290 nm. The sample preparation was conducted by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 0.4-40.0 µg/mL for midodrine (r ≥ 0.9997) and DMAE (r ≥ 0.9998). Within-day and between-day precision and accuracy were evaluated by relative standard deviations (≤ 8.2%) and relative errors (-7.3 to 7.4%), respectively. The validated method was used to assess midodrine biotransformation by the fungi Papulaspora immersa Hotson SS13, Botrytis cinerea UCA 992 and Botrytis cinerea 2100 under static and shaken conditions. Under shaken conditions, the biotransformation of midodrine to DMAE was more efficient for all studied fungi, especially for the fungus Botrytis cinerea 2100, which converted 42.2% of midodrine to DMAE.


Subject(s)
Ascomycota/metabolism , Batch Cell Culture Techniques/methods , Botrytis/metabolism , Chromatography, High Pressure Liquid/methods , Culture Media/analysis , Midodrine/analogs & derivatives , Midodrine/metabolism , Ascomycota/growth & development , Batch Cell Culture Techniques/instrumentation , Biotransformation , Botrytis/growth & development , Culture Media/metabolism , Midodrine/analysis
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