Publications by authors named "Mônica Tallarico Pupo"

32 Publications

Stingless bees and microbial interactions.

Curr Opin Insect Sci 2021 Apr 30;44:41-47. Epub 2020 Nov 30.

Departamento de Microbiologia, ICB, C.P. 486, Universidade Federal de Minas Gerais, Belo Horizonte, MG, 31270-901, Brazil. Electronic address:

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.
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http://dx.doi.org/10.1016/j.cois.2020.11.006DOI Listing
April 2021

Meliponamycins: Antimicrobials from Stingless Bee-Associated sp.

J Nat Prod 2020 03 19;83(3):610-616. Epub 2020 Feb 19.

Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café, s/n, 14040-903, Ribeirão Preto, SP, Brazil.

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 in nature encouraged us to pursue efforts to study its associated microbiota. Here we describe the discovery of two novel cyclic hexadepsipeptides, meliponamycin A () and meliponamycin B (), from sp. ICBG1318 isolated from 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 and showed strong activity against the entomopathogen and human pathogens and .
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http://dx.doi.org/10.1021/acs.jnatprod.9b01011DOI Listing
March 2020

Immunomodulating action of the 3-phenylcoumarin derivative 6,7-dihydroxy-3-[3',4'-methylenedioxyphenyl]-coumarin in neutrophils from patients with rheumatoid arthritis and in rats with acute joint inflammation.

Inflamm Res 2020 Jan 30;69(1):115-130. Epub 2019 Nov 30.

Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Avenida do Café s/n, Ribeirão Preto, SP, 14040-903, Brazil.

Objective: To examine whether free (3-PD-5) and/or liposomal (3-PD-5) 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-5 (1 µM) and 3-PD-5 (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-5 (20 µM) suppressed the release of neutrophil extracellular traps and chemotaxis in vitro, without clear signs of cytotoxicity. 3-PD-5 (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-1β, 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.
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http://dx.doi.org/10.1007/s00011-019-01298-wDOI Listing
January 2020

Microbial community modulates growth of symbiotic fungus required for stingless bee metamorphosis.

PLoS One 2019 25;14(7):e0219696. Epub 2019 Jul 25.

School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.

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.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0219696PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6657851PMC
February 2020

Paenibacillus polymyxa Associated with the Stingless Bee Melipona scutellaris Produces Antimicrobial Compounds against Entomopathogens.

J Chem Ecol 2018 Dec 23;44(12):1158-1169. Epub 2018 Oct 23.

Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café, s/n, Ribeirão Preto, SP, 14040-903, Brazil.

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.
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http://dx.doi.org/10.1007/s10886-018-1028-zDOI Listing
December 2018

Structural and biosynthetic studies on eremophilenols related to the phytoalexin capsidiol, produced by Botrytis cinerea.

Phytochemistry 2018 Oct 19;154:10-18. Epub 2018 Jun 19.

Departamento de Química Orgánica, Facultad de Ciencias, Campus Universitario Río San Pedro s/n, Torre sur, 4a planta, Universidad de Cádiz, 11510, Puerto Real, Cádiz, Spain. Electronic address:

A thorough study of the fermentation broth of three strains of Botrytis cinerea which were grown on a modified Czapek-Dox medium supplemented with 5 ppm copper sulphate, yielded five undescribed metabolites. These metabolites possessed a sesquiterpenoid (+)-4-epi-eremophil-9-ene carbon skeleton which was enantiomeric to that of the phytoalexin, capsidiol. The isolation of these metabolites when the fungus was stressed, suggests that they may be potential effectors used by B. cinerea to circumvent plant chemical defences against phytopathogenic fungi. The biosynthesis of these compounds has been studied using H and C labelled acetate.
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http://dx.doi.org/10.1016/j.phytochem.2018.06.010DOI Listing
October 2018

Chemical signaling involved in plant-microbe interactions.

Chem Soc Rev 2018 Mar;47(5):1652-1704

Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo (FCFRP-USP), Avenida do Café, s/n, 14040-903, Ribeirão Preto-SP, Brazil.

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.
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http://dx.doi.org/10.1039/c7cs00343aDOI Listing
March 2018

Expanding the Chemical Repertoire of the Endophyte Streptomyces albospinus RLe7 Reveals Amphotericin B as an Inducer of a Fungal Phenotype.

J Nat Prod 2017 05 4;80(5):1302-1309. Epub 2017 Apr 4.

Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo , Avenida do Café, s/n, Ribeirão Preto, SP 14040-903, Brazil.

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.
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http://dx.doi.org/10.1021/acs.jnatprod.6b00870DOI Listing
May 2017

Endophytic Actinobacteria from the Brazilian Medicinal Plant Lychnophora ericoides Mart. and the Biological Potential of Their Secondary Metabolites.

Chem Biodivers 2016 Jun 20;13(6):727-36. Epub 2016 May 20.

Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café s/n, 14040-903, Ribeirão Preto, SP, Brazil.

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.
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http://dx.doi.org/10.1002/cbdv.201500225DOI Listing
June 2016

Inactivation of β-Lapachone Cytotoxicity by Filamentous Fungi that Mimic the Human Blood Metabolism.

Eur J Drug Metab Pharmacokinet 2017 Apr;42(2):213-220

Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café, s/n, Ribeirão Preto, São Paulo, 14040-903, Brazil.

Background And Objectives: β-Lapachone is a drug candidate in phase II clinical trials for treatment of solid tumors. The therapeutic efficacy of β-lapachone is closely related to its metabolism, since this o-naphthoquinone produces cytotoxic effect after intracellular bioreduction by reactive oxygen species formation. The aim of this study was to produce β-lapachone human blood phase I metabolites to evaluate their cytotoxic activities.

Methods: The biotransformation of β-lapachone was performed using Mucor rouxii NRRL 1894 and Papulaspora immersa SS13. The metabolites were isolated and their chemical structures determined from spectrometric and spectroscopic data. Cell cytotoxicity assays were carried out with β-lapachone and its metabolites using the neoplastic cell line SKBR-3 derived from human breast cancer and normal human fibroblast cell line GM07492-A.

Results: Microbial transformation of β-lapachone by filamentous fungi resulted in the production of five metabolites identical to those found during human blood metabolism, a novel metabolite and a product stated before only in a synthetic procedure. The analysis of the results showed that β-lapachone metabolites were not cytotoxic for the neoplastic cell line SKBR-3 derived from human breast cancer and the normal human fibroblast cell line GM07492-A. The cytotoxic activity assay against the neoplastic cell line SKBR-3 revealed that the lowest half-maximal inhibitory concentration (IC) values of these β-lapachone metabolites were 33- to 52-fold greater than IC values of β-lapachone.

Conclusions: The cytotoxic activity of β-lapachone in vivo may be reduced due to its swift conversion in blood.
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http://dx.doi.org/10.1007/s13318-016-0337-2DOI Listing
April 2017

A new enantioselective CE method for determination of oxcarbazepine and licarbazepine after fungal biotransformation.

Electrophoresis 2014 Oct 18;35(19):2877-84. Epub 2014 Aug 18.

Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil.

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 β-CD phosphate sodium salt (P-β-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.
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http://dx.doi.org/10.1002/elps.201400137DOI Listing
October 2014

In vitro metabolism of the alkaloid piplartine by rat liver microsomes.

J Pharm Biomed Anal 2014 Jul 6;95:113-20. Epub 2014 Mar 6.

Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901 Ribeirão Preto, SP, Brazil. Electronic address:

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.
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http://dx.doi.org/10.1016/j.jpba.2014.02.020DOI Listing
July 2014

Evaluation of dispersive liquid-liquid microextraction in the stereoselective determination of cetirizine following the fungal biotransformation of hydroxyzine and analysis by capillary electrophoresis.

Talanta 2013 Nov 1;116:743-52. Epub 2013 Aug 1.

Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901 Ribeirão Preto,-SP, Brazil.

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-β-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.
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http://dx.doi.org/10.1016/j.talanta.2013.07.062DOI Listing
November 2013

Unusual biotransformation products of the sesquiterpene lactone budlein A by Aspergillus species.

Phytochemistry 2013 Dec 14;96:92-100. Epub 2013 Oct 14.

Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café s/n, 14040-903 Ribeirão Preto, SP, Brazil; Universidade Estadual de Londrina, Av. Robert Koch 60, 86039-440 Londrina, PR, Brazil.

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.
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http://dx.doi.org/10.1016/j.phytochem.2013.09.022DOI Listing
December 2013

In situ screening of 3-arylcoumarin derivatives reveals new inhibitors of mast cell degranulation.

Arch Pharm Res 2013 Jun;36(6):731-8

Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café, s/n-Campus Universitário, Ribeirão Preto, SP 14040-903, Brazil.

Due to the severity and high prevalence of allergic diseases, there is growing interest in the development of inhibitors of such conditions. 3-Arylcoumarin derivatives emerge as promising compounds for the treatment of allergic disorders, in particular due to their close structural similarity to flavonoids, whose anti-allergic activity has been extensively reported. The aim of this work was to perform a screening of a set of 3-arylcoumarins as potential inhibitors of mast cell degranulation, a key event for the development of allergic reactions. For that purpose, it was utilized a biosensor model based on mast cells, whose in vitro assay allows for such screening, in a high throughput fashion, and also permits bringing to attention some coumarin structural features that are important for their biological activity. The mast cell-based biosensor was shown to discriminate, with high sensitivity and reproducibility, between coumarins that did not affect or caused different degrees of inhibition of degranulation. Among active coumarins, some substituents could be accounted for their inhibitory activity, such as the hydroxylation of positions 6 and 2' of 3-phenylcoumarins, in addition to catechol, amino and thiophene moieties. In summary, 3-arylcoumarins could be suggested as potential candidates for the development of new anti-allergic drugs.
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http://dx.doi.org/10.1007/s12272-013-0084-8DOI Listing
June 2013

HPLC analysis of midodrine and desglymidodrine in culture medium: evaluation of static and shaken conditions on the biotransformation by fungi.

J Chromatogr Sci 2013 May-Jun;51(5):460-7. Epub 2012 Oct 9.

Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, 14040-903, Ribeirão Preto-SP, Brazil.

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.
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http://dx.doi.org/10.1093/chromsci/bms163DOI Listing
September 2013

In vitro metabolism study of the promising anticancer agent the lignan (-)-grandisin.

J Pharm Biomed Anal 2013 Jan 31;72:240-4. Epub 2012 Aug 31.

Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, 14040-903, Ribeirão Preto, São Paulo, Brazil.

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.
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http://dx.doi.org/10.1016/j.jpba.2012.08.028DOI Listing
January 2013

Solid phase microextraction and LC-MS/MS for the determination of paliperidone after stereoselective fungal biotransformation of risperidone.

Anal Chim Acta 2012 Sep 9;742:80-9. Epub 2012 Jun 9.

Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.

The present work describes for the first time the use of SPME coupled to LC-MS/MS employing the polar organic mode in a stereoselective fungal biotransformation study to investigate the fungi ability to biotransform the drug risperidone into its chiral and active metabolite 9-hydroxyrisperidone (9-RispOH). The chromatographic separation was performed on a Chiralcel OJ-H column using methanol:ethanol (50:50, v/v) plus 0.2% triethylamine as the mobile phase at a flow rate of 0.8 mL min(-1). The SPME process was performed using a C18 fiber, 30 min of extraction time and 5 min of desorption time in the mobile phase. The method was completely validated and all parameters were in agreement with the literature recommendations. The Cunninghamella echinulata fungus was able to biotransform risperidone into the active metabolite, (+)-9-RispOH, resulting in 100% of enantiomeric excess. The Cunninghamella elegans fungus was also able to stereoselectively biotransform risperidone into (+)- and (-)-9-RispOH enantiomers at different rates.
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http://dx.doi.org/10.1016/j.aca.2012.05.056DOI Listing
September 2012

Microbial transformation of the sesquiterpene lactone tagitinin C by the fungus Aspergillus terreus.

J Ind Microbiol Biotechnol 2012 Nov 11;39(11):1719-24. Epub 2012 Jul 11.

Departamento de Ciências Farmacêuticas, Universidade de São Paulo, Av. do Café s/no., Ribeirão Preto, SP 14040-903, Brazil.

The biotransformation of the sesquiterpene lactone tagitinin C by the fungus Aspergillus terreus MT 5.3 yielded a rare derivative that was elucidated by spectrometric methods. The fungus led to the formation of a different product through an unusual epoxidation reaction between C4 and C5, formation of a C3,C10 ether bridge, and a methoxylation of the C1 of tagitinin C. The chemical structure of the product, namely 1β-methoxy-3α-hydroxy-3,10β-4,5α-diepoxy-8β-isobutyroyloxygermacr-11(13)-en-6α,12-olide, is the same as that of a derivative that was recently isolated from the flowers of a Brazilian population of Mexican sunflower (Tithonia diversifolia), which is the source of the substrate tagitinin C. The in vitro cytotoxic activity of the substrate and the biotransformed product were evaluated in HL-60 cells using an MTT assay, and both compounds were found to be cytotoxic. We show that soil fungi may be useful in the biotransformation of sesquiterpene lactones, thereby leading to unusual changes in their chemical structures that may preserve or alter their biological activities, and may also mimic plant biosynthetic pathways for production of secondary metabolites.
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http://dx.doi.org/10.1007/s10295-012-1165-2DOI Listing
November 2012

Chiral HPLC analysis of donepezil, 5-O-desmethyl donepezil and 6-O-desmethyl donepezil in culture medium: application to fungal biotransformation studies.

Anal Bioanal Chem 2012 Jul 29;404(1):257-66. Epub 2012 May 29.

Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.

An high performance liquid chromatography (HPLC) method for the enantioselective determination of donepezil (DPZ), 5-O-desmethyl donepezil (5-ODD), and 6-O-desmethyl donepezil (6-ODD) in Czapek culture medium to be applied to biotransformation studies with fungi is described for the first time. The HPLC analysis was carried out using a Chiralpak AD-H column with hexane/ethanol/methanol (75:20:5, v/v/v) plus 0.3 % triethylamine as mobile phase and UV detection at 270 nm. Sample preparation was carried out by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 100-10,000 ng mL(-1) for each enantiomer of DPZ (r ≥ 0.9985) and of 100-5,000 ng mL(-1) for each enantiomer of 5-ODD (r ≥ 0.9977) and 6-ODD (r ≥ 0.9951). Within-day and between-day precision and accuracy evaluated by relative standard deviations and relative errors, respectively, were lower than 15 % for all analytes. The validated method was used to assess DPZ biotransformation by the fungi Beauveria bassiana American Type Culture Collection (ATCC) 7159 and Cunninghamella elegans ATCC 10028B. Using the fungus B. bassiana ATCC 7159, a predominant formation of (R)-5-ODD was observed while for the fungus C. elegans ATCC 10028B, DPZ was biotransformed to (R)-6-ODD with an enantiomeric excess of 100 %.
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http://dx.doi.org/10.1007/s00216-012-6107-3DOI Listing
July 2012

Assessment of the stereoselective fungal biotransformation of albendazole and its analysis by HPLC in polar organic mode.

J Pharm Biomed Anal 2012 Mar 21;61:100-7. Epub 2011 Dec 21.

Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brazil.

A high-performance liquid chromatographic method using polar organic mode was developed to analyze albendazole (ABZ), albendazole sulfone (ABZSO(2)) and the chiral and active metabolite albendazole sulfoxide (ABZSOX, ricobendazole) that was further applied in stereoselective fungal biotransformation studies. The chromatographic separation was performed on a Chiralpak AS column using acetonitrile:ethanol (97:3, v/v) plus 0.2% triethylamine and 0.2% acetic acid as the mobile phase at a flow rate of 0.5 mL min(-1). The present study employed hollow fiber liquid-phase microextraction as sample preparation. The method showed to be linear over the concentration range of 25-5000 ng mL(-1) for each ABZSOX enantiomer, 200-10,000 ng mL(-1) for ABZ and 50-1000 ng mL(-1) for ABZSO(2) metabolite with correlation coefficient (r)>0.9934. The mean recoveries for ABZ, rac-ABZSOX and ABZSO(2) were, respectively, 9%, 33% and 20% with relative standard deviation below 10%. Within-day and between-day precision and accuracy assays for these analytes were studied at three concentration levels and were lower than 15%. This study opens the door regarding the possibility of using fungi in obtaining of the active metabolite ricobendazole. Nigrospora sphaerica (Sacc.) E. W. Mason (SS67), Pestalotiopsis foedans (VR8), Papulaspora immersa Hotson (SS13) and Mucor rouxii were able to stereoselectively metabolize ABZ into its chiral metabolite. Among them, the fungus Mucor rouxii was the most efficient in the production of (+)-ABZSOX.
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http://dx.doi.org/10.1016/j.jpba.2011.12.012DOI Listing
March 2012

Ultra-fast gradient LC method for omeprazole analysis using a monolithic column: assay development, validation, and application to the quality control of omeprazole enteric-coated pellets.

J AOAC Int 2010 Nov-Dec;93(6):1811-20

Universidade de São Paulo, Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Ribeirão Preto, Brazil.

A method was optimized for the analysis of omeprazole (OMZ) by ultra-high speed LC with diode array detection using a monolithic Chromolith Fast Gradient RP 18 endcapped column (50 x 2.0 mm id). The analyses were performed at 30 degrees C using a mobile phase consisting of 0.15% (v/v) trifluoroacetic acid (TFA) in water (solvent A) and 0.15% (v/v) TFA in acetonitrile (solvent B) under a linear gradient of 5 to 90% B in 1 min at a flow rate of 1.0 mL/min and detection at 220 nm. Under these conditions, OMZ retention time was approximately 0.74 min. Validation parameters, such as selectivity, linearity, precision, accuracy, and robustness, showed results within the acceptable criteria. The method developed was successfully applied to OMZ enteric-coated pellets, showing that this assay can be used in the pharmaceutical industry for routine QC analysis. Moreover, the analytical conditions established allow for the simultaneous analysis of OMZ metabolites, 5-hydroxyomeprazole and omeprazole sulfone, in the same run, showing that this method can be extended to other matrixes with adequate procedures for sample preparation.
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March 2011

Chemical constituents of Papulaspora immersa, an endophyte from Smallanthus sonchifolius (Asteraceae), and their cytotoxic activity.

Chem Biodivers 2010 Dec;7(12):2941-50

Universidade de São Paulo, Ribeirão Preto, SP, Brazil.

Papulaspora immersa H. H. Hotson was isolated from roots and leaves of Smallanthus sonchifolius (Poepp. and Endl.) H. Rob. (Asteraceae), traditionally known as Yacon. The fungus was cultured in rice, and, from the AcOEt fraction, 14 compounds were isolated. Among them, (22E,24R)-8,14-epoxyergosta-4,22-diene-3,6-dione (4), 2,3-epoxy-1,2,3,4-tetrahydronaphthalene-c-1,c-4,8-triol (10), and the chromone papulasporin (13) were new secondary metabolites. The spectral data of the known natural products were compared with the literature data, and their structures were established as the (24R)-stigmast-4-en-3-one (1), 24-methylenecycloartan-3β-ol (2), (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (3), (-)-(3R,4R)-4-hydroxymellein (5), (-)-(3R)-5-hydroxymellein (6), 6,8-dihydroxy-3-methylisocoumarin (7), (-)-(4S)-4,8-dihydroxy-α-tetralone (8), naphthalene-1,8-diol (9), 6,7,8-trihydroxy-3-methylisocoumarin (11), 7-hydroxy-2,5-dimethylchromone (12), and tyrosol (14). Compound 4 showed the highest cytotoxic activity against the human tumor cell lines MDA-MB435 (melanoma), HCT-8 (colon), SF295 (glioblastoma), and HL-60 (promyelocytic leukemia), with IC₅₀ values of 3.3, 14.7, 5.0 and 1.6 μM, respectively. Strong synergistic effects were also observed with compound 5 and some of the isolated steroidal compounds.
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http://dx.doi.org/10.1002/cbdv.201000011DOI Listing
December 2010

LC-MS-MS determination of ibuprofen, 2-hydroxyibuprofen enantiomers, and carboxyibuprofen stereoisomers for application in biotransformation studies employing endophytic fungi.

Anal Bioanal Chem 2011 Jan 16;399(2):915-25. Epub 2010 Nov 16.

Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, 14040-903, Brazil.

The purpose of this study was the development and validation of an LC-MS-MS method for simultaneous analysis of ibuprofen (IBP), 2-hydroxyibuprofen (2-OH-IBP) enantiomers, and carboxyibuprofen (COOH-IBP) stereoisomers in fungi culture medium, to investigate the ability of some endophytic fungi to biotransform the chiral drug IBP into its metabolites. Resolution of IBP and the stereoisomers of its main metabolites was achieved by use of a Chiralpak AS-H column (150 × 4.6 mm, 5 μm particle size), column temperature 8 °C, and the mobile phase hexane-isopropanol-trifluoroacetic acid (95: 5: 0.1, v/v) at a flow rate of 1.2 mL min(-1). Post-column infusion with 10 mmol L(-1) ammonium acetate in methanol at a flow rate of 0.3 mL min(-1) was performed to enhance MS detection (positive electrospray ionization). Liquid-liquid extraction was used for sample preparation with hexane-ethyl acetate (1:1, v/v) as extraction solvent. Linearity was obtained in the range 0.1-20 μg mL(-1) for IBP, 0.05-7.5 μg mL(-1) for each 2-OH-IBP enantiomer, and 0.025-5.0 μg mL(-1) for each COOH-IBP stereoisomer (r ≥ 0.99). The coefficients of variation and relative errors obtained in precision and accuracy studies (within-day and between-day) were below 15%. The stability studies showed that the samples were stable (p > 0.05) during freeze and thaw cycles, short-term exposure to room temperature, storage at -20 °C, and biotransformation conditions. Among the six fungi studied, only the strains Nigrospora sphaerica (SS67) and Chaetomium globosum (VR10) biotransformed IBP enantioselectively, with greater formation of the metabolite (+)-(S)-2-OH-IBP. Formation of the COOH-IBP stereoisomers, which involves hydroxylation at C3 and further oxidation to form the carboxyl group, was not observed.
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http://dx.doi.org/10.1007/s00216-010-4329-9DOI Listing
January 2011

Stereoselective determination of midodrine and desglymidodrine in culture medium: application to a biotransformation study employing endophytic fungi.

Electrophoresis 2010 May;31(9):1521-8

Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.

A CE method was developed and validated for the stereoselective determination of midodrine and desglymidodrine in Czapek culture medium to be applied to a stereoselective biotransformation study employing endophytic fungi. The electrophoretic analyses were performed using an uncoated fused-silica capillary and 70 mmol/L sodium acetate buffer solution (pH 5.0) containing 30 mmol/L heptakis (2, 3, 6-tri-O-methyl)-beta-CD as running electrolyte. The applied voltage and temperature used were 15 kV and 15 degrees C, respectively. The UV detector was set at 200 nm. The sample preparation was carried out by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 0.1-12 microg/mL for each enantiomer of midodrine and desglymidodrine (r> or =0.9975). Within-day and between-day precision and accuracy evaluated by RSDs and relative errors, respectively, were lower than 15% for all analytes. The method proved to be robust by a fractional factorial design evaluation. The validated method was used to assess the midodrine biotransformation to desglymidodrine by the fungus Phomopsis sp. (TD2), which biotransformed 1.1% of (-)-midodrine to (-)-desglymidodrine and 6.1% of (+)-midodrine to (+)-desglymidodrine.
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http://dx.doi.org/10.1002/elps.200900685DOI Listing
May 2010

Enantioselective analysis of propranolol and 4-hydroxypropranolol by CE with application to biotransformation studies employing endophytic fungi.

Electrophoresis 2009 Nov;30(22):3910-7

Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.

A CE method is described for the enantioselective analysis of propranolol (Prop) and 4-hydroxypropranolol (4-OH-Prop) in liquid Czapek medium with application in the study of the enantioselective biotransformation of Prop by endophytic fungi. The electrophoretic conditions previously optimized were as follows: an uncoated fused-silica capillary, 4% w/v carboxymethyl-beta-CD in 25 mmol/L triethylamine/phosphoric acid (H(3)PO(4)) buffer at pH 9 as running electrolyte and 17 kV of voltage. UV detection was carried out at 208 nm. Liquid-liquid extraction using diethyl ether: ethyl acetate (1:1 v/v) as extractor solvent was employed for sample preparation. The calibration curves were linear over the concentration range of 0.25-10.0 microg/mL for each 4-OH-Prop enantiomer and 0.10-10.0 microg/mL for each Prop enantiomer (r>or=0.995). Within-day and between-day relative standard deviations and relative errors for precision and accuracy were lower than 15% for all the enantiomers. Finally, the validated method was used to evaluate Prop biotransformation in its mammalian metabolite 4-OH-Prop by some selected endophytic fungi. The screening of five strains of endophytic fungi was performed and all of them could biotransform Prop to some extent. Specifically, Glomerella cingulata (VA1) biotransformed 47.8% of (-)-(S)-Prop to (-)-(S)-4-OH-Prop with no formation of (+)-(R)-4-OH-Prop in 72 h of incubation.
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http://dx.doi.org/10.1002/elps.200900216DOI Listing
November 2009

Box-Behnken design for the optimization of an enantioselective method for the simultaneous analysis of propranolol and 4-hydroxypropranolol by CE.

Electrophoresis 2009 Aug;30(16):2874-81

Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.

An experimental design optimization (Box-Behnken design, BBD) was used to develop a CE method for the simultaneous resolution of propranolol (Prop) and 4-hydroxypropranolol enantiomers and acetaminophen (internal standard). The method was optimized using an uncoated fused silica capillary, carboxymethyl-beta-cyclodextrin (CM-beta-CD) as chiral selector and triethylamine/phosphoric acid buffer in alkaline conditions. A BBD for four factors was selected to observe the effects of buffer electrolyte concentration, pH, CM-beta-CD concentration and voltage on separation responses. Each factor was studied at three levels: high, central and low, and three center points were added. The buffer electrolyte concentration ranged from 25 to 75 mM, the pH ranged from 8 to 9, the CM-beta-CD concentration ranged from 3.5 to 4.5% w/v, and the applied run voltage ranged from 14 to 20 kV. The responses evaluated were resolution and migration time for the last peak. The obtained responses were processed by Minitab to evaluate the significance of the effects and to find the optimum analysis conditions. The best results were obtained using 4% w/v CM-beta-CD in 25 mM triethylamine/H3PO4 buffer at pH 9 as running electrolyte and 17 kV of voltage. Resolution values of 1.98 and 1.95 were obtained for Prop and 4-hydroxypropranolol enantiomers, respectively. The total analysis time was around of 15 min. The BBD showed to be an adequate design for the development of a CE method, resulting in a rapid and efficient optimization of the pH and concentration of the buffer, cyclodextrin concentration and applied voltage.
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http://dx.doi.org/10.1002/elps.200800821DOI Listing
August 2009

Endophytic fungi as models for the stereoselective biotransformation of thioridazine.

Appl Microbiol Biotechnol 2007 Dec 18;77(3):669-74. Epub 2007 Sep 18.

Departament of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.

The stereoselective kinetic biotransformation of thioridazine, a phenothiazine neuroleptic drug, by endophytic fungi was investigated. In general, the sulfur of lateral chain (position 2) or the sulfur of phenothiazinic ring (position 5) were oxidated yielding the major human metabolites thioridazine-2-sulfoxide and thioridazine-5-sulfoxide. The quantity of metabolites biosynthesized varied among the 12 endophytic fungi evaluated. However, mono-2-sulfoxidation occurred in higher ratio and frequency. Among the 12 fungi evaluated, 4 of them deserve prominence for presenting an evidenced stereoselective biotransformation: Phomopsis sp. (TD2), Glomerella cingulata (VA1), Diaporthe phaseolorum (VR4), and Aspergillus fumigatus (VR12). Both enantiomers of thioridazine were consumed by the fungi; however, the 2-sulfoxidation yielded preferentially the R configuration at the sulfur atom.
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http://dx.doi.org/10.1007/s00253-007-1171-xDOI Listing
December 2007

Stereoselective analysis of thioridazine-2-sulfoxide and thioridazine-5-sulfoxide: an investigation of rac-thioridazine biotransformation by some endophytic fungi.

J Pharm Biomed Anal 2008 Apr 25;46(5):945-52. Epub 2007 May 25.

Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-903, Brazil.

The purpose of this study was to develop a method for the stereoselective analysis of thioridazine-2-sulfoxide (THD-2-SO) and thioridazine-5-sulfoxide (THD-5-SO) in culture medium and to study the biotransformation of rac-thioridazine (THD) by some endophytic fungi. The simultaneous resolution of THD-2-SO and THD-5-SO diastereoisomers was performed on a CHIRALPAK AS column using a mobile phase of hexane:ethanol:methanol (92:6:2, v/v/v)+0.5% diethylamine; UV detection was carried out at 262 nm. Diethyl ether was used as extractor solvent. The validated method was used to evaluate the biotransformation of THD by 12 endophytic fungi isolated from Tithonia diversifolia, Viguiera arenaria and Viguiera robusta. Among the 12 fungi evaluated, 4 of them deserve prominence for presenting an evidenced stereoselective biotransformation potential: Phomopsis sp. (TD2) presented greater mono-2-sulfoxidation to the form (S)-(SE) (12.1%); Glomerella cingulata (VA1) presented greater mono-5-sulfoxidation to the forms (S)-(SE)+(R)-(FE) (10.5%); Diaporthe phaseolorum (VR4) presented greater mono-2-sulfoxidation to the forms (S)-(SE) and (R)-(FE) (84.4% and 82.5%, respectively) and Aspergillus fumigatus (VR12) presented greater mono-2-sulfoxidation to the forms (S)-(SE) and (R)-(SE) (31.5% and 34.4%, respectively).
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http://dx.doi.org/10.1016/j.jpba.2007.05.018DOI Listing
April 2008

The influence of culture conditions on the biosynthesis of secondary metabolites by Penicillium verrucosum Dierck.

Microbiol Res 2006 18;161(3):273-80. Epub 2005 Nov 18.

Departamento de Ciências Farmacêuticas, Universidade de São Paulo, Avenida do Café s/n, CEP 14040-903 Ribeirão Preto, SP Brazil.

A Brazilian strain of Penicillium verrucosum was cultivated under different conditions in a two-step process, in order to verify the influence of nutrients, and of time periods of pre-fermentative and fermentative steps on the biosynthesis of metabolites. Extracellular and intracellular extracts were obtained from each culture in the four different production media used. Chemical profiles of the extracts were obtained by HPLC. Extract trypanocidal activities against trypomastigote forms of Trypanosoma cruzi were evaluated. The time period of incubation in the pre-fermentative and fermentative media, as well as the different nutrients tested, qualitatively and quantitatively modified the production of secondary metabolites by P. verrucosum, and the extract trypanocidal activities.
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http://dx.doi.org/10.1016/j.micres.2005.10.003DOI Listing
August 2006
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