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1.
Steroids ; 205: 109392, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452910

RESUMO

We report the biotransformation of progesterone 1 by whole cells of Brazilian marine-derived fungi. A preliminary screening with 12 fungi revealed that the strains Penicillium oxalicum CBMAI 1996, Mucor racemous CBMAI 847, Cladosporium sp. CBMAI 1237, Penicillium oxalicum CBMAI 1185 and Aspergillus sydowii CBMAI 935 were efficient in the biotransformation of progesterone 1 in the first days of the reaction, with conversion values ranging from 75 % to 99 %. The fungus P. oxalicum CBMAI 1185 was employed in the reactions in quintuplicate to purify and characterize the main biotransformation products of progesterone 1. The compounds testololactone 1a, 12ß-hydroxyandrostenedione 1b and 1ß-hydroxyandrostenedione 1c were isolated and characterized by NMR, MS, [α]D and MP. In addition, the chromatographic yield of compound 1a was determined by HPLC-PDA in the screening experiments. In this study, we show a biotransformation pathway of progesterone 1, suggesting the presence of several enzymes such as Baeyer-Villiger monooxygenases, dehydrogenases and cytochrome P450 monooxygenases in the fungus P. oxalicum CBMAI 1185. In summary, the results obtained in this study contribute to the synthetic area and have environmental importance, since the marine-derived fungi can be employed in the biodegradation of steroids present in wastewater and the environment. The cytotoxic results demonstrate that the biodegradation products were inactive against the cell lines, in contrast to progesterone.


Assuntos
Antineoplásicos , Penicillium , Antineoplásicos/metabolismo , Cladosporium/metabolismo , Fungos/metabolismo , Oxigenases de Função Mista/metabolismo , Penicillium/metabolismo , Progesterona/metabolismo
2.
Environ Sci Pollut Res Int ; 28(28): 37082-37109, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34056690

RESUMO

Neonicotinoids are a class of pesticides widely used in different phases of agricultural crops. Similar to other classes of pesticides, they can damage human and environmental health if overused, and can be resistent to degradation. This is especially relevant to insect health, pollination, and aquatic biodiversity. Nevertheless, application of pesticides is still crucial for food production and pest control, and should therefore be carefully monitored by the government to control or reduce neonicotinoid contamination reaching human and animal feed. Aware of this problem, studies have been carried out to reduce or eliminate neonicotinoid contamination from the environment. One example of a green protocol is bioremediation. This review discusses the most recent microbial biodegradation and bioremediation processes for neonicotinoids, which employ isolated microorganisms (bacteria and fungi), consortiums of microorganisms, and different types of soils, biobeds, and biomixtures.


Assuntos
Inseticidas , Praguicidas , Animais , Biodegradação Ambiental , Biotransformação , Humanos , Fenômenos Microbiológicos , Neonicotinoides/análise
3.
Mar Biotechnol (NY) ; 22(5): 673-682, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32833111

RESUMO

In this study, we report our contribution to the application of whole cells of Brazilian marine-derived fungi in the biotransformation of ethinylestradiol 1. A preliminary screening with twelve marine-derived fungi strains revealed that the fungus Penicillium oxalicum CBMAI 1996 promoted the biotransformation of ethinylestradiol 1. Then, P. oxalicum CBMAI 1996 was employed in the reactions in decaplicate in order to purify and characterize the main biotransformation products of ethinylestradiol 1. Compounds 1b and 1c were characterized by NMR, HRMS, [α]D and mp. Compound 1b was also characterized by single crystal X-ray diffraction. In addition, kinetic monitoring of the biotransformation of ethinylestradiol 1 by P. oxalicum CBMAI 1996 was evaluated in this study in order to obtain high yields of compounds 1b and 1c with a reduction of the reaction time. In this work, we proposed a biotransformation pathway of ethinylestradiol 1, which suggests the presence of several enzymes such as phenol oxidases, monooxygenases, and ene-reductases in the fungus P. oxalicum CBMAI 1996. In summary, the rapid biodegradation of ethinylestradiol 1 and compounds 1b and 1c also has an environmental relevance, since ethinylestradiol 1 and other steroidal compounds are improperly discarded in the environment, and part of these compounds are displaced into the oceans.


Assuntos
Biotransformação , Etinilestradiol/metabolismo , Penicillium/metabolismo , Biodegradação Ambiental , Poluentes Químicos da Água/metabolismo
4.
Mar Biotechnol (NY) ; 22(3): 348-356, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32080775

RESUMO

This study applied the use of marine-derived fungus Penicillium citrinum CBMAI 1186 in the stereoselective reduction of the C=C double bond of the prochiral (E)-2-methyl-3-phenylacrylaldehyde 1. The fungus immobilized on chitosan, obtained by multistep ultrasound-assisted deacetylation process (Ch-USAD), produced the (S)-(+)-2-methyl-3-phenylpropan-1-ol 3 (c = 49%, 40% ee) isomer and (±)-2-methyl-3-phenylacrilic acid 4 (c = 35%); in contrast, immobilized mycelia on commercial chitosan (Ch-C) yielded the (S)-(+)-2-methyl-3-phenylpropan-1-ol 3 (c = 48%, 10% ee) and (±)-2-methyl-3-phenylpropanal 1a (c = 41%). The reaction using free mycelia gave a 40% yield of (S)-(+)-2-methyl-3-phenylpropan-1-ol 3 with 10% ee. These results showed that the crystallinity form and molecular weight of chitosan (Ch-C or Ch-USAD) used to immobilized mycelia of P. citrinum CBMAI 1186 influenced in the biotransformation of (E)-2-methyl-3-phenylacrylaldehyde 1. Therefore, marine-derived fungus P. citrinum CBMAI 1186 immobilized on chitosan can be a potential alternative in the studies of hydrogenation of the α,ß-unsaturated carbon-carbon (α,ß-C=C) double bond. Marine-derived fungus Penicillium citrinum CBMAI 1186 immobilized on chitosan in the stereoselective reduction of the C=C double bond of the prochiral (E)-2-methyl-3-phenylacrylaldehyde.


Assuntos
Acroleína/metabolismo , Biotransformação , Penicillium/metabolismo , Acroleína/química , Quitosana/química , Micélio , Estereoisomerismo
5.
Bioresour Technol ; 297: 122441, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31813818

RESUMO

Miniemulsion systems presented a great potential for biocatalytic reactions. However, different limitations jeopardized the applications of this non-conventional medium. In this work, miniemulsion systems (emulsion reactors) were applied for the first time to the aldol reaction between cyclohexanone and 4-nitrobenzaldehyde by Rhizopus niveus lipase allowing a decrease in the catalyst concentration from 20 mg mL-1 to 6 mg mL-1 in comparison with organic solvents. Moreover, the yield increased from ~25% to ~65% for 48 h reactions and the enantiomeric excess increased from ~10% to ~30% for (R,S)-anti-aldol product, showing the potentiality of this non-conventional reaction medium. The advances reported in this work expands the possibilities of the miniemulsion reaction medium to a whole new level, increasing the scope to solid reagents and products, and also different reactions (biocatalytic or not) that requires pH control by buffers with a simple product isolation procedure, enabling future applications of this poorly studied reaction medium.


Assuntos
Lipase , Rhizopus , Aldeídos , Biocatálise
6.
Heliyon ; 5(9): e02408, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31517128

RESUMO

In this study, we report our contribution to the application of the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction for the synthesis of ß-keto-1,2,3-triazole derivatives 3a-f from ethinylestradiol and their application in the inhibition of two human cancer cells lines: human breast adenocarcinoma (MCF-7) and human hepatocellular carcinoma (HepG2). The ß-keto-1,2,3-triazole derivates 3a-f exhibited moderate cytotoxic activity for the HepG2 cells with IC50 values of 29.7 µM (3a), 16.4 µM (3b), 17.8 µM (3c), 20.4 µM (3d), 28.1 µM (3e) and 28.2 µM (3f). The semi-synthetic ß-keto-1,2,3-triazoles derivatives 3a-f were all characterized by FT-IR, NMR, HRMS and [α]D.

7.
Front Microbiol ; 10: 1453, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31481935

RESUMO

Biodiversity has been explored in the search for novel enzymes, including forests, savannas, tundras, deserts, and finally the sea. Marine microorganisms and their enzymes are capable of being active in high-salt concentration, large range of temperature, and high incidence of light and pressure, constituting an important source of unique biocatalysts. This review presents studies employing whole-cell processes of marine bacteria and fungi, aiming for new catalysts for different reactions in organic synthesis, such as reduction, oxidation, hydroxylation, hydrolysis, elimination, and conjugation. Genomics and protein engineering studies were also approached, and reactions employing isolated enzymes from different classes (oxidoreductases, hydrolases, lyases, and ligases) were described and summarized. Future biotechnological studies and process development should focus on molecular biology for the obtention of enzymes with interesting, fascinating and enhanced properties, starting from the exploration of microorganisms from the marine environment. This review approaches the literature about the use of marine-derived bacteria, fungi, and their enzymes for biocatalytic reactions of organic compounds, promoting a discussion about the possibilities of these microorganisms in the synthesis of different substances.

8.
Chirality ; 31(7): 534-542, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31197903

RESUMO

This work reports the green organic chemistry synthesis of E-2-cyano-3(furan-2-yl) acrylamide under microwave radiation (55 W), as well as the use of filamentous marine and terrestrial-derived fungi, in the first ene-reduction of 2-cyano-3-(furan-2-yl) acrylamide to (R)-2-cyano-3-(furan-2-yl)propanamide. The fungal strains screened included Penicillium citrinum CBMAI 1186, Trichoderma sp. CBMAI 932 and Aspergillus sydowii CBMAI 935, and the filamentous terrestrial fungi Aspergillus sp. FPZSP 146 and Aspergillus sp. FPZSP 152. A compound with an uncommon CN-bearing stereogenic center at the α-C position was obtained by enantioselective reactions mediated in the presence of the microorganisms yielding the (R)-2-cyano-3-(furan-2-yl) propanamide 3a. Its isolated yield and e.e. ranged from 86% to 98% and 39% to 99%, respectively. The absolute configuration of the biotransformation products was determined by time-dependent density functional theory (TD-DFT) calculations of electronic circular dichroism (ECD) spectra. Finally, the tautomerization of 2-cyano-3-(furan-2-yl) propanamide 3a to form an achiral ketenimine was observed and investigated in presence of protic solvents.

9.
Pestic Biochem Physiol ; 156: 129-137, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027572

RESUMO

Chiral pesticides have been used in agriculture, including (±)-lambda-cyhalothrin ((±)-LC), which is a pyrethroid insecticide widely employed on crops for protection against different types of insects. However, enantioselectivity is poorly studied in biodegradation processes. Therefore, the (±)-LC enantioselective biodegradation by bacteria from Brazilian savannah was reported in this study with a validated analytical method. All bacterial strains biodegraded (±)-LC with different efficiencies. Residual concentrations of LC (3.7-43.1% of biodegradation) and its enantiomeric excesses (0-27% ee) were determined. Additionally, the formation of the main biodegradation metabolite 3-phenoxybenzoic acid was also quantified. A Bacillus consortium composed of the three most efficient strains biodegraded more LC than any isolated strain solely employed in this work, showing that the use of a consortium is an interesting approach. In addition, 13 metabolites were identified and a biodegradation pathway with biochemical reactions of hydrolysis, reduction, esterification, amidation, elimination and group transfer were proposed, confirming the bioremediation potential of these strains. The LC stereoisomer with the highest insecticidal activity (1R,3R,αS-enantiomer, also known as gamma-cyhalothrin) was preferentially biodegraded by the studied bacteria. Therefore, crops protection with gamma-cyhalothrin, which can be applied in lower concentrations than (±)-LC because it is a more effective product against insects, may also be biodegraded faster than the racemic mixture in the environment, decreasing the toxic effects on non-target organisms.


Assuntos
Bactérias/metabolismo , Nitrilas/farmacologia , Piretrinas/farmacologia , Bacillus/metabolismo , Biodegradação Ambiental , Inseticidas/farmacologia , Praguicidas/farmacologia , Estereoisomerismo
10.
Chirality ; 30(7): 890-899, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29693740

RESUMO

This paper reports the enantioseparation of ß-hydroxy-1,2,3-triazole derivatives, which present a broad range of biological properties, by supercritical fluid chromatography (SFC) and high-performance liquid chromatography techniques (HPLC). Polysaccharide-based chiral columns (cellulose and amylose) were used to evaluate the separation in SFC and HPLC. Time of analyses, consumption of solvent, and parameter optimization were reduced using SFC technique. The columns based on cellulose chiral stationary phase using 2-propanol and ethanol as modifiers showed the best results for the enantioresolution of the (±)-ß-hydroxy-1,2,3-triazoles by SFC analyses. These techniques were applied to evaluate the selectivity of biocatalytic reduction of ß-keto-1,2,3-triazoles by marine-derived fungus Penicillium citrinum CBMAI 1186 to obtain the (±)-ß-hydroxy-1,2,3-triazoles.

11.
Chemosphere ; 197: 651-660, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29407829

RESUMO

The contamination of agricultural lands by pesticides is a serious environmental issue. Consequently, the development of bioremediation methods for different active ingredients, such as pyrethroids, is essential. In this study, the enantioselective biodegradation of (±)-lambda-cyhalothrin ((±)-LC) by marine-derived fungi was studied. Experiments were performed with different fungi strains (Aspergillus sp. CBMAI 1829, Acremonium sp. CBMAI 1676, Microsphaeropsis sp. CBMAI 1675 and Westerdykella sp. CBMAI 1679) in 3% malt liquid medium with 100 mg L-1 of (±)-LC. All strains biodegraded this insecticide and the residual concentrations of (±)-LC (79.2-55.2 mg L-1, i.e., 20.8-44.8% biodegradation), their enantiomeric excesses (2-42% ee) and the 3-phenoxybenzoic acid (PBAc) concentrations (0.0-4.1 mg L-1) were determined. In experiments for 28 days of biodegradation in the absence and presence of artificial seawater (ASW) with the most efficient strain Aspergillus sp. CBMAI 1829, increasing concentrations of PBAc with (0.0-4.8 mg L-1) and without ASW (0.0-15.3 mg L-1) were observed. In addition, a partial biodegradation pathway was proposed. All the evaluated strains biodegraded preferentially the (1R,3R,αS)-gamma-cyhalothrin enantiomer. Therefore, marine-derived fungi enantioselectively biodegraded (±)-LC and can be applied in future studies for bioremediation of contaminated areas. This enantioselective biodegradation indicates that the employment of the most active enantiomer GC as insecticide not only enable the use of a lower amount of pesticide, but also a more easily biodegradable product, reducing the possibility of environmental contamination.


Assuntos
Biodegradação Ambiental , Fungos/metabolismo , Inseticidas/metabolismo , Nitrilas/metabolismo , Piretrinas/metabolismo , Água do Mar/microbiologia , Aspergillus/metabolismo , Benzoatos , Praguicidas/metabolismo
12.
Mar Pollut Bull ; 129(2): 525-533, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29055563

RESUMO

The biodegradation of polycyclic aromatic hydrocarbons (PAHs) by marine-derived fungi was reported in this work. Marine-derived fungi (Trichoderma harzianum CBMAI 1677, Cladosporium sp. CBMAI 1237, Aspergillus sydowii CBMAI 935, Penicillium citrinum CBMAI 1186 and Mucor racemosus CBMAI 847) biodegraded anthracene (14days, 130rpm, 50mgmL-1 initial concentration in malt 2% medium). Cladosporium sp. CBMAI 1237 was the most efficient strain and biodegraded more anthracene in the presence (42% biodegradation) than in the absence (26%) of artificial seawater, suggesting that the biodegradation of PAHs may be faster in seawater than in non-saline environment. After 21days, Cladosporium sp. CBMAI 1237 biodegraded anthracene (71% biodegradation), anthrone (100%), anthraquinone (32%), acenaphthene (78%), fluorene (70%), phenanthrene (47%), fluoranthene (52%), pyrene (62%) and nitropyrene (64%). Previous undocumented metabolites were identified and, anthraquinone was a common product of different PAHs biodegradation. The marine-derived fungus Cladosporium sp. CBMAI 1237 showed potential for bioremediation of PAHs.


Assuntos
Cladosporium/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Antracenos/análise , Antracenos/metabolismo , Biodegradação Ambiental , Brasil , Cladosporium/isolamento & purificação , Modelos Teóricos , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Água do Mar/microbiologia , Poluentes Químicos da Água/metabolismo
13.
Mar Biotechnol (NY) ; 18(4): 511-20, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27381569

RESUMO

Esfenvalerate biodegradation by marine-derived fungi is reported here. Esfenvalerate (S,S-fenvalerate) and its main metabolites [3-phenoxybenzaldehyde (PBAld), 3-phenoxybenzoic acid (PBAc), 3-phenoxybenzyl alcohol (PBAlc), and 2-(4-chlorophenyl)-3-methylbutyric acid (CLAc)] were quantitatively analyzed by a validated method in triplicate experiments. All the strains (Penicillium raistrickii CBMAI 931, Aspergillus sydowii CBMAI 935, Cladosporium sp. CBMAI 1237, Microsphaeropsis sp. CBMAI 1675, Acremonium sp. CBMAI 1676, Westerdykella sp. CBMAI 1679, and Cladosporium sp. CBMAI 1678) were able to degrade esfenvalerate, however, with different efficiencies. Initially, 100 mg L(-1) esfenvalerate (Sumidan 150SC) was added to each culture in 3 % malt liquid medium. Residual esfenvalerate (64.8-95.2 mg L(-1)) and the concentrations of PBAc (0.5-7.4 mg L(-1)), ClAc (0.1-7.5 mg L(-1)), and PBAlc (0.2 mg L(-1)) were determined after 14 days. In experiments after 7, 14, 21, and 28 days of biodegradation with the three most efficient strains, increasing concentrations of the toxic compounds PBAc (2.7-16.6 mg L(-1), after 28 days) and CLAc (6.6-13.4 mg L(-1), after 28 days) were observed. A biodegradation pathway was proposed, based on HPLC-ToF results. The biodegradation pathway includes PBAld, PBAc, PBAlc, ClAc, 2-hydroxy-2-(3-phenoxyphenyl)acetonitrile, 3-(hydroxyphenoxy)benzoic acid, and methyl 3-phenoxy benzoate. Marine-derived fungi were able to biodegrade esfenvalerate in a commercial formulation and showed their potential for future bioremediation studies in contaminated soils and water bodies.


Assuntos
Acremonium/metabolismo , Aspergillus/metabolismo , Cladosporium/metabolismo , Nitrilas/metabolismo , Penicillium/metabolismo , Praguicidas/metabolismo , Piretrinas/metabolismo , Poluentes Químicos da Água/metabolismo , Benzaldeídos/metabolismo , Benzoatos/metabolismo , Álcoois Benzílicos/metabolismo , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Poluentes do Solo/metabolismo
14.
Mar Biotechnol (NY) ; 17(6): 736-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26272428

RESUMO

Seven strains of marine-derived fungi (Aspergillus sclerotiorum CBMAI 849, Cladosporium cladosporioides CBMAI 857, Penicillium raistrickii CBMAI 931, Penicillium citrinum CBMA 1186, Mucor racemosus CBMAI 847, Beauveria felina CBMAI 738, and Penicillium oxalicum CBMAI 1185) and terrestrial fungus Penicillium chrysogenum CBMA1199 were screened as catalysts for the asymmetric reduction of α-keto azides 5-8 to their corresponding ß-azidophenylethanols 9-12. The marine fungi showed Prelog and anti-Prelog selectivities to the reduction α-keto azides 5-8. The fungi A. sclerotiorum CBMAI 849, C. cladosporioides CBMAI 857, P. raistrickii CBMAI 931, and P. citrinum CBMA 1186 catalyzed the reduction of azido ketone 6 to the corresponding (R)-2-azido-1-(4-methoxyphenyl)ethanol (10) with good conversions (68-100 %) and excellent enantiomeric excesses (>99 % ee) according to Prelog rule.


Assuntos
Organismos Aquáticos/metabolismo , Azidas/metabolismo , Biodegradação Ambiental , Fungos/metabolismo , Cetonas/metabolismo , Aspergillus/metabolismo , Beauveria/metabolismo , Catálise , Cladosporium/metabolismo , Mucor/metabolismo , Penicillium/metabolismo , Penicillium chrysogenum/metabolismo , Estereoisomerismo
15.
Biotechnol Adv ; 33(5): 481-510, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25687277

RESUMO

This review presents the recent research in biocatalysis and biotransformation in Brazil. Several substrates were biotransformed by fungi, bacteria and plants. Biocatalytic deracemization of secondary alcohols, oxidation of sulfides, sp(3) CH hydroxylation and epoxidation of alkenes were described. Chemo-enzymatic resolution of racemic alcohols and amines were carried out with lipases using several substrates containing heteroatoms such as silicon, boron, selenium and tellurium. Biotransformation of nitriles by marine fungi, hydrolysis of epoxides by microorganisms of Brazilian origin and biooxidation of natural products were described. Enzymatic reactions under microwave irradiation, continuous flow, and enzymatic assays using fluorescent probes were reported.


Assuntos
Bactérias/metabolismo , Biocatálise , Biotecnologia/métodos , Biotransformação , Fungos/metabolismo , Brasil , Oxirredução
16.
Mar Biotechnol (NY) ; 17(2): 211-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25634054

RESUMO

A screening was performed using nine marine-derived fungi as biocatalysts and the natural products (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) in order to select the microorganisms able to catalyze the biooxidation of these compounds. It was observed that only the Aspergillus sydowii CBMAI 934, Botryosphaeria sp., Eutypella sp., and Xylaria sp. presented active oxidoreductases and catalyzed the regioselective hydroxylation in the natural products. The hydroxylated metabolites obtained were 1ß-hydroxy-ambrox (1a) (14%, A. sydowii CBMAI 934); 3ß-hydroxy-ambrox (1b) (17%, Botryosphaeria sp.; 11%, Eutypella sp.); 3ß-hydroxy-sclareol (2a) (31%, Xylaria sp.; 69%, Botryosphaeria sp.; 55%, Eutypella sp.); 18-hydroxy-sclareol (2b) (10%, Xylaria sp.); and 3ß-hydroxy-sclareolide (3a) (34%, Botryosphaeria sp.; 7%, Eutypella sp.). This is the first report of biohydroxylation of (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) by whole mycelia of marine-derived fungi.


Assuntos
Aspergillus/metabolismo , Produtos Biológicos/metabolismo , Diterpenos/metabolismo , Furanos/metabolismo , Naftalenos/metabolismo , Penicillium/metabolismo , Poríferos/microbiologia , Animais , Oceano Atlântico , Biotransformação , Brasil , Catálise , Diterpenos/química , Furanos/química , Hidroxilação , Estrutura Molecular , Naftalenos/química , Oxirredução
17.
Chemosphere ; 117: 47-52, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24955826

RESUMO

Seven marine fungi strains (Aspergillus sydowii CBMAI 934, A. sydowii CBMAI 935, A. sydowii CBMAI 1241, Penicillium decaturense CBMAI 1234, Penicillium raistrickii CBMAI 931, P. raistrickii CBMAI 1235, and Trichoderma sp. CBMAI 932) were screened by their growth in the presence of methyl parathion (MP) in a solid culture medium. The strains with best growth were A. sydowii CBMAI 935 and P. decaturense CBMAI 1234. Biodegradation reactions were performed in 10, 20 and 30d in a malt extract liquid medium containing commercial MP and whole cells of A. sydowii CBMAI 935 and P. decaturense CBMAI 1234. In 20d, A. sydowii CBMAI 935 was able to degrade all pesticide, whereas P. decaturense CBMAI 1234 promoted a complete degradation in 30d. A. sydowii CBMAI 935 and P. decaturense CBMAI 1234 could degrade the product of the MP enzymatic hydrolysis, p-nitrophenol, on average of 51 and 40% respectively. Both strains used MP as a sole source of carbon and provided satisfactory results. Metabolites detected in the medium showed that the presumable reaction pathway occurred through the activation of MP to its more toxic form, methyl paraoxon, which was further degraded to p-nitrophenol.


Assuntos
Aspergillus/crescimento & desenvolvimento , Metil Paration/análise , Penicillium/crescimento & desenvolvimento , Microbiologia da Água , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Hidrólise , Metil Paration/química , Estrutura Molecular , Oxirredução , Poluentes Químicos da Água/química
18.
Molecules ; 17(8): 8955-67, 2012 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-22836214

RESUMO

The lipase B from Candida antarctica (Novozym 435®, CALB) efficiently catalyzed the kinetic resolution of some aliphatic secondary alcohols: (±)-4-methylpentan-2-ol, (±)-5-methylhexan-2-ol, (±)-octan-2-ol, (±)-heptan-3-ol and (±)-oct-1-en-3-ol. The lipase showed excellent enantioselectivities in the transesterifications of racemic aliphatic secondary alcohols producing the enantiopure alcohols (>99% ee) and acetates (>99% ee) with good yields. Kinetic resolution of rac-alcohols was successfully achieved with CALB lipase using simple conditions, vinyl acetate as acylating agent, and hexane as non-polar solvent.


Assuntos
Acetatos/isolamento & purificação , Álcoois Graxos/isolamento & purificação , Proteínas Fúngicas/química , Lipase/química , Acetatos/química , Biocatálise , Candida/enzimologia , Esterificação , Álcoois Graxos/química , Hexanos/química , Solventes/química , Estereoisomerismo , Especificidade por Substrato , Compostos de Vinila/química
19.
Mar Biotechnol (NY) ; 14(4): 396-401, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22653656

RESUMO

Nine marine fungi (Aspergillus sclerotiorum CBMAI 849, Aspergillus sydowii Ce19, Beauveria felina CBMAI 738, Mucor racemosus CBMAI 847, Penicillium citrinum CBMAI 1186, Penicillium miczynskii Ce16, P. miczynskii Gc5, Penicillium oxalicum CBMAI 1185, and Trichoderma sp. Gc1) catalyzed the asymmetric bioconversion of iodoacetophenones 1-3 to corresponding iodophenylethanols 6-8. All the marine fungi produced exclusively (S)-ortho-iodophenylethanol 6 and (S)-meta-iodophenylethanol 7 in accordance to the Prelog rule. B. felina CBMAI 738, P. miczynskii Gc5, P. oxalicum CBMAI 1185, and Trichoderma sp. Gc1 produced (R)-para-iodophenylethanol 8 as product anti-Prelog. The bioconversion of para-iodoacetophenone 3 with whole cells of P. oxalicum CBMAI 1185 showed competitive reduction-oxidation reactions.


Assuntos
Aspergillus/metabolismo , Compostos de Iodo/metabolismo , Cetonas/metabolismo , Penicillium/metabolismo , Trichoderma/metabolismo , Microbiologia da Água , Aspergillus/classificação , Biotransformação , Oceanos e Mares , Penicillium/classificação , Especificidade da Espécie , Trichoderma/classificação
20.
Mar Biotechnol (NY) ; 14(3): 358-62, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22160343

RESUMO

Nine strains of marine-derived fungi (Aspergillus sydowii Ce15, A. sydowii Ce19, Aspergillus sclerotiorum CBMAI 849, Bionectria sp. Ce5, Beauveria felina CBMAI 738, Cladosporium cladosporioides CBMAI 857, Mucor racemosus CBMAI 847, Penicillium citrinum CBMAI 1186, and Penicillium miczynskii Gc5) were screened, catalyzing the asymmetric bioreduction of 1-(4-methoxyphenyl)ethanone 1 to its corresponding 1-(4-methoxyphenyl)ethanol 2. A. sydowii Ce15 and Bionectria sp. Ce5 produced the enantiopure (R)-alcohol 2 (>99% ee) in accordance with the anti-Prelog rule and, the fungi B. felina CBMAI 738 (>99% ee) and P. citrinum CBMAI 1186 (69% ee) in accordance with the Prelog rule. Stereoselective bioreduction by whole cells of marine-derived fungi described by us is important for the production of new reductases from marine-derived fungi.


Assuntos
Acetofenonas/química , Acetofenonas/metabolismo , Fungos/classificação , Fungos/metabolismo , Microbiologia da Água , Acetofenonas/isolamento & purificação , Água do Mar , Especificidade da Espécie , Estereoisomerismo
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