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1.
Environ Monit Assess ; 195(1): 126, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36401680

RESUMO

The current study focused on the monitoring of pollution loads in the Kalpakkam coastal zone of India in terms of physico-chemical characteristics of sediment. The investigation took place at 12 sampling points around the Kalpakkam coastal zone for one year beginning from 2019. The seasonal change of nutrients in the sediment, such as nitrogen, phosphorus, potassium, total organic carbon, and particles size distribution, was calculated. Throughout the study period, the pH (7.55 to 8.99), EC (0.99 to 4.98 dS/m), nitrogen (21.74 to 58.12 kg/ha), phosphorus (7.5 to 12.9 kg/ha), potassium (218 to 399 kg/ha), total organic carbon (0.11 to 0.88%), and particle size cumulative percent of sediments (from 9.01 to 9.39%) was observed. A number of multivariate statistical techniques were used to examine the changes in sediment quality. The population means were substantially different according to the three-way ANOVA test at the 0.05 level. Principal component analysis and cluster analysis showed a substantial association with all indicators throughout all seasons, implying contamination from both natural and anthropogenic causes. The ecosystem of the Kalpakkam coastal zone has been affected by nutrient contamination.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Baías , Carbono/análise , Ecossistema , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Nitrogênio/análise , Fósforo/análise , Potássio/análise , Poluentes Químicos da Água/análise , Oceano Índico
2.
Heliyon ; 8(11): e11480, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36387572

RESUMO

A new zinc-based boron nitride (Zn-BNT) material was synthesized from boron nitride and zinc acetate in 95% yield. The morphological and spectroscopic properties of Zn-BNT were elucidated by SEM, XRD, BET, DSC-TGA, and FT-IR. Zn-BNT catalyzed the synthesis of benzimidazoles (3a-3h) through a reaction between o-phenylenediamine and different aromatic aldehydes under microwave conditions for 15 min. The compounds were purified by silica-gel chromatography. The synthesized compounds were characterized by FT-IR, 1H-NMR, 13C-NMR, and elemental analysis. Zn-BNT was reused eight times with only a 5% loss of catalytic activity. Furthermore, 2-(4-fluorophenyl)-1H-benzo[d]imidazole (3f) was selected for a computational study of the IR and NMR spectrum, which matched the experimentally generated spectra. The HOMO-LUMO gap was 4.48, and the Fukui function analysis showed high activity in the reactive sites.

3.
Nutr Cancer ; 71(7): 1165-1174, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945951

RESUMO

Aim: Hepatocellular carcinoma is one of the leading global epidemics. A medicinal tree, Moringa oleifera (MO), has been part of traditional treatments including cancer therapies. We investigated the apoptosis inducing effects of MO crude aqueous leaf extract (MOE) in human liver hepatocellular carcinoma (HepG2) cells. Methods: HepG2, PBMCs and Hek293 cell viability was evaluated using MTT assay. Oxidative stress and DNA damage was determined using TBARS and comet assays, respectively. Apoptosis was assessed by caspase-9, -3/7 activities and ATP levels (luminometry). Cell cycle, γH2AX, and cleaved PARP-1 were determined (flow cytometry). Protein expression of c-myc, Bax, p-Bcl2, Smac/DIABLO, Hsp70, SRp30a and cleaved PARP-1 was assessed using western blotting. Results: MOE displayed minimal toxicity in PBMCs and Hek293 cells for 24 h. HepG2 cells were exposed to MOE (24 h) and an IC50 (4.479 mg/mL) was determined. MOE significantly increased lipid peroxidation, DNA damage and γH2AX levels. A significant decrease in G1, S and G2-M phase was seen. Significant increase in SRp30a protein expression activated caspase-9. Caspase-9 and -3/7 was significantly increased with significant decrease in ATP levels. Apoptosis was confirmed with significant decrease in c-myc, p-Bcl2 and Hsp70 protein expression and a significant increase in Bax, Smac/DIABLO and PARP-1 cleavage. Conclusion: MOE induces cell-cycle arrest and apoptosis in cancerous HepG2 cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Neoplasias Hepáticas/metabolismo , Moringa oleifera/química , Extratos Vegetais/farmacologia , Trifosfato de Adenosina/metabolismo , Caspases/metabolismo , Dano ao DNA/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Histonas/metabolismo , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Folhas de Planta/química , Poli(ADP-Ribose) Polimerase-1/metabolismo
4.
Biomed Pharmacother ; 108: 457-466, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30241049

RESUMO

Cancer is classified as one of the leading causes of global mortality. It has affected millions of people, often with poor prognosis. Having severe side-effects with conventional chemotherapy, alternate drugs and therapies are actively being investigated. There is a need for innovative drug discovery and design as existing cancer therapies are costly and not readily available. Ayurveda and traditional medicine have utilised natural resources such as plants and trees as part of their regime to treat various illness and diseases with positive outcomes. One such tree is Moringa oleifera (MO). Almost all parts have shown to be effective against several ailments including cancer which was attributed to the bioactive constituents. Targeted therapies had led to the development of nanoparticles which are extremely effective in various biomedical applications due to their small size. Green synthesis of gold nanoparticles have great potential as naturally occurring plants and trees such as MO can be used in the synthesis process. The resultant gold phytonanoparticles are useful in cancer therapies with improved survival rates and quality of life. The review highlights the importance of MO in natural medicine, synthesis of phytonanoparticles and the fundamental role as a potential antiproliferative agent against cancer.


Assuntos
Proliferação de Células/efeitos dos fármacos , Moringa oleifera/química , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Humanos , Nanopartículas Metálicas/química , Neoplasias/metabolismo , Qualidade de Vida , Taxa de Sobrevida
5.
J Photochem Photobiol B ; 169: 75-82, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28288401

RESUMO

The bio-synthesized DTAuNPs have an average size of 21nm. The aggregation extent depends on the concentration of melamine, which was validated by UV-vis spectra and visual method of melamine detection was developed. The major observation in this method was the color change of DTAuNPs from red to purple due to the aggregation of ligand capped gold nanoparticles instigated by melamine. The reaction of color changes were processed due to the shifting of bonding in hydrogen in between nanoparticles and melamine. The aggregation extent depends on the concentration of melamine, which can be validated UV-vis spectra and visual method of detecting melamine is developed. The electron density and conventional UV-vis, FTIR spectroscopy and DFT studies on the ligand was performed using computational methods. The theoretical and experimental data for the energy transitions and the molar extinction coefficients of the ligands studied has been obtained. Further, the ligand capped gold nanoparticles was assessed for cytotoxicity against A549 cells which resulted in significant decrease in cell viability was noted in 50µg/mL DTAu, 4-ATP and AXT treated cells at 2h (85% and 66%) and 6h (83% and 36%) respectively, (p<0.01) were studied and reported in this manuscript.


Assuntos
Nanopartículas Metálicas/química , Triazinas/análise , Células A549 , Aminas , Sobrevivência Celular/efeitos dos fármacos , Cor , Ouro/química , Humanos , Ligantes , Limite de Detecção , Técnicas Psicológicas , Análise Espectral , Compostos de Sulfidrila
6.
J Cell Biochem ; 117(10): 2302-14, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26923760

RESUMO

Gold nanoparticles (AuNP's) facilitate cancer cell recognition and can be manufactured by green synthesis using nutrient rich medicinal plants such as Moringa oleifera (MO). Targeting dysregulated oncogenes and tumor suppressor genes is crucial for cancer therapeutics. We investigated the antiproliferative effects of AuNP synthesized from MO aqueous leaf extracts (MLAuNP ) in A549 lung and SNO oesophageal cancer cells. A one-pot green synthesis technique was used to synthesise MLAuNP . A549, SNO cancer cells and normal peripheral blood mononuclear cells (PBMCs) were exposed to MLAuNP and CAuNP to evaluate cytotoxicity (MTT assay); apoptosis was measured by phosphatidylserine (PS) externalization, mitochondrial depolarization (ΔΨm) (flow cytometry), caspase-3/7, -9 activity, and ATP levels (luminometry). The mRNA expression of c-myc, p53, Skp2, Fbw7α, and caspase-9 splice variants was determined using qPCR, while relative protein expression of c-myc, p53, SRp30a, Bax, Bcl-2, Smac/DIABLO, Hsp70, and PARP-1 were determined by Western blotting. MLAuNP and CAuNP were not cytotoxic to PBMCs, whilst its pro-apoptotic properties were confirmed in A549 and SNO cells. MLAuNP significantly increased caspase activity in SNO cells while MLAuNP significantly increased PS externalization, ΔΨm, caspase-9, caspase-3/7 activities, and decreased ATP levels in A549 cells. Also, p53 mRNA and protein levels, SRp30a (P = 0.428), Bax, Smac/DIABLO and PARP-1 24 kDa fragment levels were significantly increased. Conversely, MLAuNP significantly decreased Bcl-2, Hsp70, Skp2, Fbw7α, c-myc mRNA, and protein levels and activated alternate splicing with caspase-9a splice variant being significantly increased. MLAuNP possesses antiproliferative properties and induced apoptosis in A549 cells by activating alternate splicing of caspase-9. J. Cell. Biochem. 117: 2302-2314, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ouro/química , Neoplasias Pulmonares/patologia , Nanopartículas Metálicas/administração & dosagem , Moringa oleifera/química , Extratos Vegetais/farmacologia , Splicing de RNA/genética , Células A549 , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 9/genética , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Genes Supressores de Tumor/efeitos dos fármacos , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Nanopartículas Metálicas/química , Oncogenes/efeitos dos fármacos , Células Tumorais Cultivadas
7.
PLoS One ; 10(7): e0129874, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26134408

RESUMO

Increased death rates due to lung cancer have necessitated the search for potential novel anticancer compounds such as carbazole derivatives. Carbazoles are aromatic heterocyclic compounds with anticancer, antibacterial and anti-inflammatory activity. The study investigated the ability of the novel carbazole compound (Z)-4-[9-ethyl-9aH-carbazol-3-yl) amino] pent-3-en-2-one (ECAP) to induce cytotoxicity of lung cancer cells and its mechanism of action. ECAP was synthesized as a yellow powder with melting point of 240-247 °C. The 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), lipid peroxidation and comet assays were used to assess the cytotoxic effect of the compound on A549 lung cancer cells. Protein expression was determined using western blots, apoptosis was measured by luminometry (caspase-3/7, -8 and -9) assay and flow cytometry was used to measure phosphatidylserine (PS) externalisation. ECAP induced a p53 mediated apoptosis of lung cancer cells due to a significant reduction in the expression of antioxidant defence proteins (Nrf2 and SOD), Hsp70 (p < 0.02) and Bcl-2 (p < 0.0006), thereby up-regulating reactive oxygen species (ROS) production. This resulted in DNA damage (p < 0.0001), up-regulation of Bax expression and caspase activity and induction of apoptosis in lung cancer cells. The results show the anticancer potential of ECAP on lung cancer.


Assuntos
Carbazóis/farmacologia , Citotoxinas/farmacologia , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Pentanonas/farmacologia , Apoptose/efeitos dos fármacos , Carbazóis/síntese química , Caspases/genética , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas/síntese química , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Peroxidação de Lipídeos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pentanonas/síntese química , Fosfatidilserinas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Transdução de Sinais , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/agonistas , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
8.
Acta Crystallogr D Biol Crystallogr ; 71(Pt 2): 313-23, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25664741

RESUMO

CO2 fixation is thought to be one of the key factors in mitigating global warming. Of the various methods for removing CO2, the NAD-dependent formate dehydrogenase from Candida boidinii (CbFDH) has been widely used in various biological CO2-reduction systems; however, practical applications of CbFDH have often been impeded owing to its low CO2-reducing activity. It has recently been demonstrated that the NAD-dependent formate dehydrogenase from Thiobacillus sp. KNK65MA (TsFDH) has a higher CO2-reducing activity compared with CbFDH. The crystal structure of TsFDH revealed that the biological unit in the asymmetric unit has two conformations, i.e. open (NAD(+)-unbound) and closed (NAD(+)-bound) forms. Three major differences are observed in the crystal structures of TsFDH and CbFDH. Firstly, hole 2 in TsFDH is blocked by helix α20, whereas it is not blocked in CbFDH. Secondly, the sizes of holes 1 and 2 are larger in TsFDH than in CbFDH. Thirdly, Lys287 in TsFDH, which is crucial for the capture of formate and its subsequent delivery to the active site, is an alanine in CbFDH. A computational simulation suggested that the higher CO2-reducing activity of TsFDH is owing to its lower free-energy barrier to CO2 reduction than in CbFDH.


Assuntos
Dióxido de Carbono/metabolismo , Formiato Desidrogenases/metabolismo , Thiobacillus/enzimologia , Candida/química , Candida/enzimologia , Candida/metabolismo , Cristalografia por Raios X , Formiato Desidrogenases/química , Modelos Moleculares , NAD/metabolismo , Oxirredução , Conformação Proteica , Termodinâmica , Thiobacillus/química , Thiobacillus/metabolismo
9.
Steroids ; 95: 73-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25528196

RESUMO

Chemical investigation of the crude methanolic extract of Buxus macowanii resulted in the isolation of five new steroidal alkaloids, 31-hydroxybuxatrienone (1), macowanioxazine (2), 16α-hydroxymacowanitriene (3), macowanitriene (4), macowamine (5), along with five known steroidal bases, Nb-demethylpapillotrienine (6), moenjodaramine (7), irehine (8), buxbodine B (9) and buxmicrophylline C (10). Structures of compounds 1-10 were elucidated with the aid of spectroscopic methods including 1D and 2D NMR techniques and mass spectrometry. Compounds 1, 3, and 4 belong to a rare class of Buxus alkaloids having Δ(1,2) 9(10→19) abeo triene system. All isolates were evaluated for in vitro acetylcholinesterase (AChE) inhibitory activity and found to exhibit moderate to weak anti-AChE activity with IC50 values in the range of 10.8-98µM. Compounds 1 and 6 were also moderately active in BACE1 inhibitory assay.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Buxus/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Esteroides/química , Acetilcolinesterase/metabolismo , Alcaloides/isolamento & purificação , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Inibidores da Colinesterase/isolamento & purificação , Concentração Inibidora 50
10.
J Nanobiotechnology ; 11: 5, 2013 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-23418790

RESUMO

BACKGROUND: Silver nanoparticles (AgNP), the most popular nano-compounds, possess unique properties. Albizia adianthifolia (AA) is a plant of the Fabaceae family that is rich in saponins. The biological properties of a novel AgNP, synthesized from an aqueous leaf extract of AA (AA(AgNP)), were investigated on A549 lung cells. Cell viability was determined by the MTT assay. Cellular oxidative status (lipid peroxidation and glutathione (GSH) levels), ATP concentration, caspase-3/-7, -8 and -9 activities were determined. Apoptosis, mitochondrial (mt) membrane depolarization (flow cytometry) and DNA fragmentation (comet assay) were assessed. The expression of CD95 receptors, p53, bax, PARP-1 and smac/DIABLO was evaluated by flow cytometry and/or western blotting. RESULTS: Silver nanoparticles of AA caused a dose-dependent decrease in cell viability with a significant increase in lipid peroxidation (5-fold vs. control; p = 0.0098) and decreased intracellular GSH (p = 0.1184). A significant 2.5-fold decrease in cellular ATP was observed upon AA(AgNP) exposure (p = 0.0040) with a highly significant elevation in mt depolarization (3.3-fold vs. control; p < 0.0001). Apoptosis was also significantly higher (1.5-fold) in AA(AgNP) treated cells (p < 0.0001) with a significant decline in expression of CD95 receptors (p = 0.0416). Silver nanoparticles of AA caused a significant 2.5-fold reduction in caspase-8 activity (p = 0.0024) with contrasting increases in caspase-3/-7 (1.7-fold vs. control; p = 0.0180) and -9 activity (1.4-fold vs. control; p = 0.0117). Western blots showed increased expression of smac/DIABLO (4.1-fold) in treated cells (p = 0.0033). Furthermore, AA(AgNP) significantly increased the expression of p53, bax and PARP-1 (1.2-fold; p = 0.0498, 1.6-fold; p = 0.0083 and 1.1-fold; p = 0.0359 respectively). CONCLUSION: Data suggests that AA(AgNP) induces cell death in the A549 lung cells via the mt mediated intrinsic apoptotic program. Further investigation is required to potentiate the use of this novel compound in cancer therapy trials.


Assuntos
Albizzia/química , Apoptose/efeitos dos fármacos , Nanopartículas Metálicas/química , Prata/química , Western Blotting , Caspase 3/metabolismo , Caspase 7/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Fragmentação do DNA/efeitos dos fármacos , Glutationa/análise , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias Pulmonares/metabolismo , Nanopartículas Metálicas/análise , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Folhas de Planta/química , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Prata/análise , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo , Receptor fas/metabolismo
11.
J Nat Prod ; 73(11): 1858-62, 2010 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-20954721

RESUMO

Acetylcholinesterase (AChE) inhibition-directed phytochemical studies on the methanolic extract of Buxus natalensis, collected in South Africa, resulted in the isolation of 12 compounds: O(2)-natafuranamine (1), O(10)-natafuranamine (2), cyclonataminol (3), 31-demethylbuxaminol A (4), buxaminol A (5), buxafuranamide (6), buxalongifolamidine (7), buxamine A (8), cyclobuxophylline K (9), buxaminol C (10), methyl syringate (11), and p-coumaroylputrescine (12). Compounds 1-4 were new alkaloids, and compound 5 was isolated for the first time as a natural product. Their structures were elucidated with the aid of extensive NMR and mass spectroscopic studies. Compounds 1 and 2 are members of a rarely occurring class of Buxus alkaloids, having a tetrahydrofuran ring incorporated in their structures. Compounds 1-12 exhibited strong to moderate AChE inhibitory activity.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Buxus/química , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Plantas Medicinais/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Alcaloides/química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , África do Sul , Triterpenos/química
12.
Molecules ; 15(5): 3171-8, 2010 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-20657469

RESUMO

An efficient synthesis of a methyl derivative of the indoloquinoline alkaloid cryptosanguinolentine based on microwave-assisted reactions is described. The microwave-assisted synthesis of an intermediate 4-hydroxy-2-methylquinoline yielded 86% of the desired product and other intermediates prepared yielded high % of products in shorter reaction times, under optimum conditions, as compared to traditional methods.


Assuntos
Hidroxiquinolinas/síntese química , Alcaloides Indólicos/síntese química , Quinaldinas/síntese química , Alcaloides/síntese química , Indolquinonas/síntese química , Metilação , Micro-Ondas
13.
Prep Biochem Biotechnol ; 36(4): 297-306, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16971301

RESUMO

Among the enzymatic steps in the aflatoxin biosynthetic pathway, the conversion of O-methylsterigmatocystin (OMST) to the potent environmental carcinogen aflatoxin B1 (AFB1), has been proposed to be catalysed by an oxidoreductase (OR) that requires a cytochrome P-450 type of oxidoreductase activity. This enzyme displays relative specificity towards OMST homologues in fungal whole cells. These studies were extended to the action of a cell-free enzyme system (CFES), on five OMST homologues, with a view to establish the kinetics. In the current study a CFES, containing an oxidoreductase, was derived from a blocked mutant of Aspergillus parasiticus (Wh1-11-105). The key experimental steps involved rapid concentration and efficient dialysis by membrane filtration to remove small biomolecules (MW<10,000), co-factors, primary and secondary metabolites. The kinetic parameters of the enzyme-substrate reactions indicated that the reaction follows a Michealis-Menten kinetics and OR activity decreased in the order: O-butylsterigmatocystin>O-propylsterigmatocystin>O-ethylsterigmatocystin>O-methylsterigmatocystin>O-acetylsterigmatocystin>O-benzoylsterigmatocystin. The 7-O-alkyl homologues were the best substrate for the CFES, thereby substantially supporting that the 7-O-methyl group of OMST is preferred for OR catalytic activity in the absence of any other alkylating groups in vitro. The Km was calculated as 5.65 microM for this CFES and varied marginally among the OMST homologues studied.


Assuntos
Aflatoxina B1/biossíntese , Sistema Enzimático do Citocromo P-450/química , Oxirredutases/química , Esterigmatocistina/análogos & derivados , Sistema Livre de Células/enzimologia , Sistema Enzimático do Citocromo P-450/análise , Cinética , Oxirredutases/análise , Esterigmatocistina/metabolismo
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