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1.
J Hazard Mater ; 450: 131091, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36870095

RESUMO

Butylated hydroxytoluene (BHT), as an emerging contaminant in ecosystems, has potential influences on animals, aquatic organisms, and public health, and has been proven to be a major allelochemical of Pinellia ternata. In this study, Bacillus cereus WL08 was used to rapidly degrade BHT in liquid culture. Strain WL08 immobilized on tobacco stem charcoal (TSC) particles notably accelerated BHT removal in contract to its free cells, and exhibited excellent reutilization and storage capacities. The optimal removal parameters of TSC WL08 were ascertained to be pH 7.0, 30 °C, 50 mg L-1 BHT and 0.14 mg L-1 TSC WL08. Moreover, TSC WL08 significantly accelerated the degradation of 50 mg L-1 BHT in sterile and non-sterile soils compared to that of free WL08 or natural dissipation, and notably shortened their half-lives by 2.47- or 362.14- fold, and 2.20- or 14.99- fold, respectively. Simultaneously, TSC WL08 was introduced into the continuous cropping soils of P. ternata, which accelerated the elimination of allelochemical BHT, and notably enhanced the photosynthesis, growth, yield, and quality of P. ternata. This study provides new insights and strategies for the rapid in situ remediation of BHT-polluted soils and effective alleviation of P. ternata cropping obstacles.


Assuntos
Pinellia , Solo , Animais , Solo/química , Hidroxitolueno Butilado/metabolismo , Bacillus cereus , Pinellia/química , Pinellia/metabolismo , Carvão Vegetal/metabolismo , Ecossistema
2.
Environ Sci Technol ; 56(20): 14562-14573, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36198135

RESUMO

Ultraviolet (UV) absorbents and industrial antioxidants are contaminants of emerging concern (CECs), but little is known about their distribution in Arctic wildlife, as well as how these contaminants vary over time, across regions, and between species. We used archived egg samples to examine the temporal patterns of 26 UV absorbents and industrial antioxidants in three seabird species (black-legged kittiwakes Rissa tridactyla, thick-billed murres Uria lomvia, northern fulmars Fulmarus glacialis) sampled in Arctic Canada between 1975 and 2019. Various synthetic phenolic antioxidants, aromatic secondary amines, benzotriazole UV stabilizers, and organic UV filters were detected in the seabird eggs. Overall, kittiwakes had higher levels of several UV absorbents and industrial antioxidants. Most target contaminants reached their peak concentrations at different points during the 44-year study period or did not vary significantly over time. None of these contaminant concentrations have increased in recent years. The antioxidant 2-6-di-tert-butyl-4-methylphenol (BHT) was the most frequently detected contaminant in seabird eggs, and its level significantly declined over the course of the study period in kittiwake eggs but did not change in the eggs of murres and fulmars. Future research should examine the effects of these CECs on the health of avian species, the sources, and exposure pathways of these contaminants.


Assuntos
Charadriiformes , Poluentes Ambientais , Animais , Aminas/metabolismo , Antioxidantes/metabolismo , Regiões Árticas , Aves , Hidroxitolueno Butilado/análise , Hidroxitolueno Butilado/metabolismo , Canadá , Charadriiformes/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/análise , Estudos Retrospectivos , Ovos
3.
Metab Eng ; 73: 26-37, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35671979

RESUMO

The demand for bio-based retinol (vitamin A) is currently increasing, however its instability represents a major bottleneck in microbial production. Here, we developed an efficient method to selectively produce retinol in Yarrowia lipolytica. The ß-carotene 15,15'-dioxygenase (BCO) cleaves ß-carotene into retinal, which is reduced to retinol by retinol dehydrogenase (RDH). Therefore, to produce retinol, we first generated ß-carotene-producing strain based on a high-lipid-producer via overexpressing genes including heterologous ß-carotene biosynthetic genes, GGS1F43I mutant of endogenous geranylgeranyl pyrophosphate synthase isolated by directed evolution, and FAD1 encoding flavin adenine dinucleotide synthetase, while deleting several genes previously known to be beneficial for carotenoid production. To produce retinol, 11 copies of BCO gene from marine bacterium 66A03 (Mb.Blh) were integrated into the rDNA sites of the ß-carotene overproducer. The resulting strain produced more retinol than retinal, suggesting strong endogenous promiscuous RDH activity in Y. lipolytica. The introduction of Mb.Blh led to a considerable reduction in ß-carotene level, but less than 5% of the consumed ß-carotene could be detected in the form of retinal or retinol, implying severe degradation of the produced retinoids. However, addition of the antioxidant butylated hydroxytoluene (BHT) led to a >20-fold increase in retinol production, suggesting oxidative damage is the main cause of intracellular retinol degradation. Overexpression of GSH2 encoding glutathione synthetase further improved retinol production. Raman imaging revealed co-localization of retinol with lipid droplets, and extraction of retinol using Tween 80 was effective in improving retinol production. By combining BHT treatment and extraction using Tween 80, the final strain CJ2104 produced 4.86 g/L retinol and 0.26 g/L retinal in fed-batch fermentation in a 5-L bioreactor, which is the highest retinol production titer ever reported. This study demonstrates that Y. lipolytica is a suitable host for the industrial production of bio-based retinol.


Assuntos
Yarrowia , Antioxidantes , Hidroxitolueno Butilado/metabolismo , Detergentes/metabolismo , Polissorbatos/metabolismo , Vitamina A/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , beta Caroteno/metabolismo
4.
Folia Microbiol (Praha) ; 67(5): 793-799, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35622275

RESUMO

Endophytic fungi are rich sources of structurally complex chemical scaffolds with interesting biological activities. However, their metabolome is still unknown, making them appealing for novel compound discovery. To maximize the number of secondary metabolites produced from a single microbial source, we used the "OSMAC (one strain-many compounds) approach." In potato dextrose medium, M. phaseolina produced phomeolic acid (1), ergosterol peroxide (2), and a volatile compound 1,4-benzene-diol. Incorporating an epigenetic modifier, sodium valproate, affected the metabolite profile of the fungus. It produced 3-acetyl-3-methyl dihydro-furan-2(3H)-one (3) and methyl-2-(methyl-thio)-butyrate (4), plus volatile chemicals: butylated hydroxy toluene (BHT), di-methyl-formamide, 3-amino-1-propanol, and 1,4-benzenediol, 2-amino-1-(O-methoxyphenyl) propane. The structure of compounds 1-4 was established with the help of spectroscopic data. This study revealed first-time compounds 1-4 in the fungus M. phaseolina using a classical and epigenetic manipulation approach.


Assuntos
Ascomicetos , Brugmansia , Ascomicetos/metabolismo , Benzeno/metabolismo , Hidroxitolueno Butilado/metabolismo , Butiratos/metabolismo , Endófitos/química , Epigênese Genética , Formamidas/metabolismo , Furanos/metabolismo , Glucose/metabolismo , Propano/metabolismo , Tolueno/metabolismo , Ácido Valproico/metabolismo
5.
Chem Res Toxicol ; 35(5): 840-848, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35416036

RESUMO

Biotransformation, especially by human CYP450 enzymes, plays a crucial role in regulating the toxicity of organic compounds in organisms, but is poorly understood for most emerging pollutants, as their numerous "unusual" biotransformation reactions cannot retrieve examples from the textbooks. Therefore, in order to predict the unknown metabolites with altering toxicological profiles, there is a realistic need to develop efficient methods to reveal the "unusual" metabolic mechanism of emerging pollutants. Combining experimental work with computational predictions has been widely accepted as an effective approach in studying complex metabolic reactions; however, the full quantum chemical computations may not be easily accessible for most environmentalists. Alternatively, this work practiced using the concepts from physical organic chemistry for studying the interrelationships between structure and reactivity of organic molecules, to reveal the "unusual" metabolic mechanism of synthetic phenolic antioxidants catalyzed by CYP450, for which the simple pencil-and-paper and property-computation methods based on physical organic chemistry were performed. The phenol-coupling product of butylated hydroxyanisole (BHA) (based on spin aromatic delocalization) and ipso-addition quinol metabolite of butylated hydroxytoluene (BHT) (based on hyperconjugative effect) were predicted as two "unusual" metabolites, which were further confirmed by our in vitro analysis. We hope this easily handled approach will promote environmentalists to attach importance to physical organic chemistry, with an eye to being able to use the knowledge gained to efficiently predict the fates of substantial unknown synthesized organic compounds in the future.


Assuntos
Antioxidantes , Poluentes Ambientais , Hidroxianisol Butilado/análise , Hidroxianisol Butilado/química , Hidroxianisol Butilado/metabolismo , Hidroxitolueno Butilado/análise , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/metabolismo , Química Orgânica , Sistema Enzimático do Citocromo P-450 , Poluentes Ambientais/análise , Humanos , Fenóis/análise
6.
Drug Chem Toxicol ; 45(4): 1899-1906, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34013795

RESUMO

Butylated hydroxyanisole (BHA) and the chemically similar butylated hydroxytoluene (BHT) are widely used as antioxidants. Toxicity of BHA and BHT has been reported under in vitro and in vivo experimental conditions. However, the mechanism of BHA-induced toxic effects in cells is unclear. In this study, the cytotoxic effects of BHA and differences in cell death mechanism for BHA and BHT were investigated in rat thymocytes by flow cytometric analysis using a fluorescent probe. We observed a significant increase in propidium iodide fluorescence in the population of cells treated with 100 µM and 300 µM BHA (dead cells). Thymocytes treated with 100 µM BHA showed increased intracellular Ca2+ and Zn2+ levels and depolarized cell membranes. BHA (30-100 µM) decreased non-protein thiol content of cells, indicating decreased glutathione content. Co-stimulation with 100 µM BHA and 300 µM H2O2 acted synergistically to increase cell lethality. Moreover, BHA significantly increased caspase-3 activity and the number of annexin-V-positive cells in a concentration-dependent manner, indicating apoptosis. However, BHT reduced caspase-3 activity and increased the number of annexin-V-negative dead cells, indicating non-apoptotic cell death. Our results reveal the toxicity of BHA could be attributed to increased levels of intracellular Ca2+ and Zn2+, resulting in an increased vulnerability of rat thymocytes to oxidative stress. In addition, we demonstrate that whereas BHA induced apoptosis, BHT induced non-apoptotic cell death in rat thymocytes. Therefore, these results may support the safety of BHA, but also demonstrate the importance of performing toxicity evaluation at the cellular level besides the tissue level.


Assuntos
Hidroxianisol Butilado , Hidroxitolueno Butilado , Animais , Anexinas , Antioxidantes/farmacologia , Apoptose , Hidroxianisol Butilado/metabolismo , Hidroxianisol Butilado/toxicidade , Hidroxitolueno Butilado/metabolismo , Hidroxitolueno Butilado/toxicidade , Cálcio/metabolismo , Caspase 3/metabolismo , Peróxido de Hidrogênio/metabolismo , Ratos , Zinco/metabolismo
7.
Nutrients ; 13(9)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34578952

RESUMO

Leiomyoma is the most common benign uterine tumor in reproductive-age women. Increasing numbers of studies are focusing on the effects of environmental exposure on the incidence and progression of tumors. One major step taken in the food industry is the addition of food preservatives to maintain freshness. Butylated hydroxytoluene (BHT) is a synthetic phenolic antioxidant, which is widely used as an additive to develop fat-soluble characteristics, as well as in cosmetics and rubber. Previous studies also highlighted that BHT may be related to increased fibrosis capacity and carcinogenic effects. In this study, we explored the effects of the commonly used food additive BHT on leiomyoma progression, and the related mechanism. The exposure of the ELT-3 leiomyoma cell line to BHT for 48 h increased the proliferative effect. Since leiomyoma progression is related to increases in extracellular matrix (ECM) accumulation and matrix metalloproteinase (MMP), BHT could effectively increase ECM-related protein expression, as well as MMP-2 and MMP-9 protein expression. This increase in ECM, in response to BHT, may be linked to the activation of the phosphoinositide 3-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) signaling pathway. Through PI3K inhibition, BHT's effect on leiomyoma progression could be partially modulated. These results suggest the harmful effect of BHT exposure on leiomyoma progression may relate to PI3K modulation. However, an in vivo study is necessary to confirm these findings.


Assuntos
Hidroxitolueno Butilado/metabolismo , Proliferação de Células/efeitos dos fármacos , Matriz Extracelular/metabolismo , Aditivos Alimentares/metabolismo , Leiomioma/metabolismo , Neoplasias Uterinas/metabolismo , Hidroxitolueno Butilado/efeitos adversos , Linhagem Celular Tumoral , Progressão da Doença , Matriz Extracelular/efeitos dos fármacos , Feminino , Aditivos Alimentares/efeitos adversos , Humanos
8.
Food Chem ; 353: 129488, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33714793

RESUMO

Synthetic phenolic antioxidants can interact with peroxides produced by food. This paper reviews correlation between BHA, BHT and TBHQ metabolism and harms they cause and provides a theoretical basis for rational use of BHA, BHT and TBHQ in food, and also put some attention on the transformation and metabolic products of PG. We introduce BHA, BHT, TBHQ, PG and their possible metabolic pathways, and discuss possible harms and their specific mechanisms responsible. Excessive addition or incorrect use of synthetic phenolic antioxidants results in carcinogenicity, cytotoxicity, oxidative stress induction and endocrine disrupting effects, which warrant attention. BHA carcinogenicity is related to production of metabolites TBHQ and TQ, and cytotoxic effect of BHA is the main cause of apoptosis induction. BHT carcinogenicity depends on DNA damage degree, and tumour promotion is mainly related to production of quinone methylation metabolites. TBHQ carcinogenicity is related to induction of metabolite TQ and enzyme CYP1A1.


Assuntos
Antioxidantes/síntese química , Fenóis/química , Animais , Antioxidantes/metabolismo , Antioxidantes/toxicidade , Apoptose/efeitos dos fármacos , Hidroxianisol Butilado/química , Hidroxianisol Butilado/metabolismo , Hidroxianisol Butilado/toxicidade , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/metabolismo , Hidroxitolueno Butilado/toxicidade , Aditivos Alimentares/química , Aditivos Alimentares/metabolismo , Aditivos Alimentares/toxicidade , Humanos , Hidroquinonas/química , Hidroquinonas/metabolismo , Hidroquinonas/toxicidade
9.
Int J Mol Sci ; 21(24)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333739

RESUMO

Butylated hydroxytoluene (BHT) and its analogs, butylated hydroxyanisole (BHA) and tert-butyl-hydroquinone (TBHQ), are widely used synthetic preservatives to inhibit lipid oxidation in the food, cosmetic and pharmaceutical industries. Despite their widespread use, little is known about their human exposure and related biotransformation products. The metabolism of these compounds was investigated using in vitro incubations with human and rat liver fractions. Liquid chromatography coupled to high-resolution tandem mass spectrometry was employed to detect and characterize stable and reactive species formed via oxidative metabolism, as well as phase II conjugates. Several oxidative metabolites have been detected, as well as glutathione, glucuronide, and sulfate conjugates, many of which were not previously reported. A combination of accurate mass measurements, MS/MS fragmentation behavior, and isotope-labeling studies were used to elucidate metabolite structures.


Assuntos
Antioxidantes/análise , Hidroxianisol Butilado/metabolismo , Hidroxitolueno Butilado/metabolismo , Animais , Antioxidantes/química , Hidroxianisol Butilado/análogos & derivados , Hidroxianisol Butilado/química , Hidroxitolueno Butilado/análogos & derivados , Hidroxitolueno Butilado/química , Cromatografia Líquida , Glucuronídeos/análise , Glutationa/análise , Humanos , Técnicas In Vitro , Microssomos/metabolismo , Fenóis/análise , Fenóis/metabolismo , Ratos , Sulfatos/análise , Espectrometria de Massas em Tandem
10.
J Agric Food Chem ; 68(16): 4670-4677, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32064879

RESUMO

One typical synthetic phenolic antioxidant 2,6-di-tert-butyl-hydroxytoluene (BHT) is widely used in foodstuff. Concerns are rising on the toxicity of BHT and its metabolites through dietary exposure. In this study, the effects of food macronutrients (i.e., lipid, carbohydrate, fiber, protein, and fasted (as control)) on absorption and bioaccessibility of BHT by Caco-2 cells were investigated. Food components decreased the absorption and bioaccessibility by Caco-2 cells. The highest absorption rate by Caco-2 cells was fasted state (first-order rate constant = 4.26 h-1), followed by carbohydrate (2.36 h-1), fiber (1.39 h-1), lipid (1.34 h-1), and protein (1.15 h-1). The order of bioaccessibility of BHT and its metabolites was fasted (100 ± 11.5%) > protein (83.1 ± 2.69%) > fiber (65.8 ± 2.67%) > carbohydrate (56.8 ± 1.58%) ≈ lipid (56.7 ± 0.82%). A solid-phase microextraction test together with a computational in vitro kinetic model suggested that the macronutrients may bind to BHT to reduce its free concentration and decrease the bioaccessibility. To our knowledge, this is the first study to report food influence on the absorption and bioaccessibility of BHT by Caco-2 cells. Results here can provide important implications for the safety regulation for dietary synthetic phenolic antioxidants.


Assuntos
Antioxidantes/metabolismo , Hidroxitolueno Butilado/metabolismo , Antioxidantes/síntese química , Disponibilidade Biológica , Transporte Biológico , Hidroxitolueno Butilado/síntese química , Células CACO-2 , Análise de Alimentos , Humanos , Cinética
11.
Fish Shellfish Immunol ; 72: 220-229, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29108969

RESUMO

A 10-week growth trail was conducted to investigate the efficacy and tolerance of dietary butylated hydroxytoluene (BHT) by evaluating inflammation, apoptosis and hepatic disease related to oxidative stress in largemouth bass (Micropterus salmoides). Four experimental diets were prepared with BHT supplement levels of 0 (B0), 150 (B150), 300 (B300) and 1500 (B1500) mg/kg, in which B150 was at the maximum recommended level established by European Union Regulation, and the B300 and B1500 levels were 2 and 10-fold of B150, respectively. Each diet was fed to 6 replicates with 30 largemouth bass (initial body weight, IBW = 6.20 ± 0.01 g) in each tank. The BHT inclusion level did not affect the specific growth rate, but fish in the B150 group showed the lowest feed conversion rate (P < 0.05). BHT inclusion significantly decreased the levels of plasma TC, TG, LDL, ALT and AKP, and increased the (HDL-C)/TC ratio (P < 0.05). Plasma MDA was significantly decreased in the B150 group and GSH-Px was extremely enhanced in each BHT inclusion group (P < 0.05). Hepatic T-AOC was significantly enhanced and O2- was significantly decreased in each BHT inclusion group compared to the B0 group (P < 0.05), as well as hepatic MDA was significantly decreased in B1500 group (P < 0.05). Dietary BHT inclusion down-regulated the hepatic mRNA levels of inflammation, apoptosis and fibrosis related genes, including TNFα, TGF-ß1, α-SMA, IL8, IL11ß and caspase-9. Moreover, BHT could improve hepatic lipid metabolism via up-regulating the mRNA levels of APOA1, CYP7A1, CYP8B1, and down-regulating the mRNA levels of PPAR-γ and APOB. Histological examination of the liver morphology with H&E and Sirius Red staining showed that BHT inclusion decreased necrotic degenerative changes and collagen deposition in largemouth bass. An immunofluorescence examination revealed significantly decreased cleaved caspase-3 signals in the BHT groups. In conclusion, the results demonstrated that ROS induces hepatic cell apoptosis and fibrosis via the intrinsic pathway of apoptosis by activating caspase-9 in the mitochondria and then initiates apoptosis by activating caspase-3. Consuming 2.32-23.80 mg/kg·bw/d (150-1500 mg/kg in diet) of BHT effectively improved the plasma and hepatic lipid metabolism, antioxidant response as well as reduced ROS production, protecting hepatic cells from injury. It is implied that even a 10-fold increase of the maximum level of BHT (150 mg/kg) is safe for the largemouth bass.


Assuntos
Antioxidantes/metabolismo , Apoptose , Bass/imunologia , Hidroxitolueno Butilado/metabolismo , Ração Animal/análise , Animais , Antioxidantes/administração & dosagem , Bass/crescimento & desenvolvimento , Bass/metabolismo , Hidroxitolueno Butilado/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Metabolismo dos Lipídeos
12.
Cryobiology ; 72(2): 112-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26929990

RESUMO

Heterocyclic derivatives of butylated hydroxytoluene (BHT) were studied as cryoprotectants of the basic media for cryopreservation of the Russian sturgeon sperm. Rates of lipid peroxidation of sturgeon sperm before and after cryopreservation were reduced in the presence of the studied compounds, exceeding the effects of BHT and water-soluble analogue of vitamin E, trolox. The most efficient antioxidant has the effective concentration of 0.1 mM. Novel antioxidant agents as cryomedium supplements not only reduced the level of lipid peroxidation, but also enhanced the translational motility of the sperm of the Russian sturgeon after defrosting.


Assuntos
Antioxidantes/farmacologia , Hidroxitolueno Butilado/farmacologia , Criopreservação/métodos , Crioprotetores/farmacologia , Peixes/fisiologia , Espermatozoides/efeitos dos fármacos , Animais , Hidroxitolueno Butilado/metabolismo , Cromanos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Fenóis/metabolismo
13.
Cryobiology ; 69(3): 467-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25445463

RESUMO

A cryoprotective effect of an addition of a new synthetic antioxidant - a representative of phosphorus-containing sterically hindered phenols is presented. The efficiency of the compound was shown to exceed the effect of lipid-soluble antioxidants butylated hydroxytoluene (BHT) and trolox in the conditions of cryopreservation of beluga sperm in the presence of the modified Stein's medium. It was shown that the level of carbonyl oxidation by-products, which can react with thiobarbituric acid (TBARS), in beluga sperm was inversely proportional to the motility time of sperm cells. The fertility of beluga sperm increased 2 times upon the addition of phosphorus-containing phenol to a modified Stein's medium. The prospects of the new antioxidant application to improve cryoresistance of beluga sperm in the conditions of cryopreservation for its efficient protection from the peroxidation processes are discussed.


Assuntos
Antioxidantes/metabolismo , Criopreservação/veterinária , Crioprotetores/metabolismo , Peixes/fisiologia , Fenóis/metabolismo , Preservação do Sêmen/veterinária , Espermatozoides/citologia , Animais , Antioxidantes/química , Beluga , Hidroxitolueno Butilado/metabolismo , Cromanos/metabolismo , Criopreservação/métodos , Crioprotetores/química , Feminino , Fertilização , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Fenóis/química , Fósforo/química , Fósforo/metabolismo , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo
14.
Environ Toxicol Chem ; 33(2): 308-16, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24173968

RESUMO

In silico-based model predictions, originating from structural and mechanistic (e.g., transport, bioavailability, reactivity, and binding potential) profiling, were compared against laboratory-derived data to estimate the bioaccumulation potential in earthworms of 2 organic substances (1 neutral, 1 ionogenic) known to primarily partition to soil. Two compounds representative of specific classes of chemicals were evaluated: a nonchlorinated bisphenol containing an -OH group (4,4'-methylenebis[2,6-di-tert-butylphenol] [Binox]), and an ionogenic xanthene dye (2',4',5',7'-tetrabromo-4,5,6,7-tetrachloro-3',6'-dihydroxy-, disodium salt [Phloxine B]). Soil bioaccumulation studies were conducted using Eisenia andrei and 2 field-collected soils (a clay loam and a sandy soil). In general, the in silico structural and mechanistic profiling was consistent with the observed soil bioaccumulation tests. Binox did not bioaccumulate to a significant extent in E. andrei in either soil type; however, Phloxine B not only accumulated within tissue, but was not depurated from the earthworms during the course of the elimination phase. Structural and mechanistic profiling demonstrated the binding and reactivity potential of Phloxine B; this would not be accounted for using traditional bioaccumulation metrics, which are founded on passive-based diffusion mechanisms. This illustrates the importance of profiling for reactive ionogenic substances; even limited bioavailability combined with reactivity can result in exposures to a hazardous substance not predictable by traditional in silico modeling methods.


Assuntos
Hidroxitolueno Butilado/análogos & derivados , Azul de Eosina I/metabolismo , Corantes Fluorescentes/metabolismo , Modelos Teóricos , Oligoquetos/metabolismo , Poluentes do Solo/metabolismo , Animais , Disponibilidade Biológica , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/metabolismo , Simulação por Computador , Azul de Eosina I/química , Corantes Fluorescentes/química , Solo , Poluentes do Solo/química
15.
J Photochem Photobiol B ; 126: 112-8, 2013 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-23911863

RESUMO

The binding properties of butylated hydroxytoluene (BHT) with calf thymus DNA (ctDNA) in simulated physiological buffer (pH 7.4) were investigated using ethidium bromide (EB) dye as a fluorescence probe by various spectroscopic techniques including UV-vis absorption, fluorescence, circular dichroism (CD), and Fourier transform infrared (FT-IR) spectroscopy along with ctDNA melting studies and viscosity measurements. It was found that the binding of BHT to ctDNA could decrease the absorption intensity of ctDNA, significantly increase melting temperature and relative viscosity of ctDNA, and induce the changes in CD spectra. Moreover, the competitive binding studies showed that BHT was able to displace EB from the bound ctDNA-EB complex. All the experimental results indicated that the binding mode between BHT and ctDNA was an intercalation. The association constants between BHT and ctDNA were evaluated to be (4.78±0.04)×10(3), (2.86±0.02)×10(3) and (1.80±0.04)×10(3) L mol(-)(1) at 298, 304, 310K, respectively. Further, the FT-IR analysis revealed that BHT was more prone to interact with adenine and thymine base pairs, and no significant conformational transition of ctDNA occurred. Thermodynamic analysis of the binding data showed that the binding process was primarily driven by hydrogen bonds and van der Waals forces, as the values of the enthalpy change and the entropy change were calculated to be -62.47±0.07kJ mol(-)(1) and -139.22±0.22J mol(-)(1) K(-)(1), respectively.


Assuntos
Hidroxitolueno Butilado/metabolismo , DNA/metabolismo , DNA/química , Etídio/química , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Desnaturação de Ácido Nucleico , Termodinâmica , Temperatura de Transição
16.
Zhongguo Zhong Yao Za Zhi ; 38(2): 284-8, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23672058

RESUMO

OBJECTIVE: To study the chemical components of essential oils from Meconopsis oliverana and their antioxidant activity. METHOD: The essential oil was extracted by steam distillation, and GC-MS analysis was used to identify its constituents. The OH free radical scavenging activity of the essential oils was evaluated with an enzyme mark instrument by assay of the ability of DPPH free radical scavenging. BHT was used as positive control. RESULT: Forty-seven compounds, account for 91.866% of the essential oils, were identified. The ability of scavenging OH and DPPH radicals of the essential oils is stronger than that of BHT. CONCLUSION: The main chemical constituents of the essential oils from M. oliverana are n-hexadecanoic acid (27.653%) and 6,10,14-trimethyl-2-pentadecanone (16.330%). And the essential oils showed strong antioxidant activity.


Assuntos
Antioxidantes/química , Óleos Voláteis/química , Papaveraceae/química , Óleos de Plantas/química , Antioxidantes/metabolismo , Compostos de Bifenilo/metabolismo , Hidroxitolueno Butilado/metabolismo , China , Álcoois Graxos/química , Álcoois Graxos/isolamento & purificação , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Radical Hidroxila/metabolismo , Óleos Voláteis/isolamento & purificação , Oxirredução , Ácido Palmítico/química , Ácido Palmítico/isolamento & purificação , Picratos/metabolismo , Óleos de Plantas/isolamento & purificação
17.
Biomed Khim ; 58(6): 712-26, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23350203

RESUMO

Using the chemiluminescence method, the effective concentration of antioxidants (AO) and its reactivity toward peroxyl radicals (ARA, the k7 constant) have been measured for 13 plant extracts. In fact all extracts demonstrated ARA higher than ionol. Larix dahurica, Hypericum perforatum, Potentilla fruticosa, Aronia melanocarpa and Rhaponticum carthamoides extracts showed the highest values of ARA. The combinations Aronia + Raponticum extracts; Larix + Hibiscus extracts; Schizandra +Aronia extracts were synergistic (the synergism effect beta of 38%, 33% and 22%). Apparently this phenomenon is the result of the synergistic interaction between compounds present in plant extracts. The Phospholipid complex--Lipoid S40, lacting any antioxidant effect alone, showed a potent synergistic effect with Aronia extract (beta3 = 60%), Silybum extract (beta3 = 41%). Clinical trials demonstrated, that combinations "Lipoid + Aronia extract", "Lipoid + Larix extract + Hibiscus extract", "Lipoid + Silybum extract", "Lipoid + Q10 + Rosa majalis extract" may be used as an additional component in the medicinal treatment, or as an individual prophylactic agent.


Assuntos
Antioxidantes/análise , Doenças Cardiovasculares/tratamento farmacológico , Hepatopatias/tratamento farmacológico , Fosfolipídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Doenças Urológicas/tratamento farmacológico , Antioxidantes/química , Antioxidantes/metabolismo , Bilirrubina/metabolismo , Hidroxitolueno Butilado/química , Hidroxitolueno Butilado/metabolismo , Doenças Cardiovasculares/sangue , Colesterol/sangue , Doença Crônica , Humanos , Hypericum/química , Leuzea/química , Medições Luminescentes , Isquemia Miocárdica/tratamento farmacológico , Fosfolipídeos/uso terapêutico , Photinia/química , Extratos Vegetais/uso terapêutico , Substâncias Protetoras/farmacologia , Rosaceae/química , Schisandra/química , Triglicerídeos/sangue
18.
Molecules ; 16(12): 10134-45, 2011 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-22146374

RESUMO

BACKGROUND AND AIM: Clitoria ternatea, a medicinal herb native to tropical equatorial Asia, is commonly used in folk medicine to treat various diseases. The aim of the present study is to evaluate the hepatoprotective and antioxidant activity of C. ternatea against experimentally induced liver injury. METHODS: The antioxidant property of methanolic extract (ME) of C. ternatea leaf was investigated by employing an established in vitro antioxidant assay. The hepatoprotective effect against paracetamol-induced liver toxicity in mice of ME of C. ternatea leaf was also studied. Activity was measured by monitoring the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and billirubin along with histopathological analysis. RESULTS: The amount of total phenolics and flavonoids were estimated to be 358.99 ± 6.21 mg/g gallic acid equivalent and 123.75 ± 2.84 mg/g catechin equivalent, respectively. The antioxidant activity of C. ternatea leaf extract was 67.85% at a concentration of 1 mg/mL and was also concentration dependant, with an IC(50) value of 420.00 µg/mL. The results of the paracetamol-induced liver toxicity experiments showed that mice treated with the ME of C. ternatea leaf (200 mg/kg) showed a significant decrease in ALT, AST, and bilirubin levels, which were all elevated in the paracetamol group (p < 0.01). C. ternatea leaf extract therapy also protective effects against histopathological alterations. Histological studies supported the biochemical findings and a maximum improvement in the histoarchitecture was seen. CONCLUSIONS: The current study confirmed the hepatoprotective effect of C. ternatea leaf extract against the model hepatotoxicant paracetamol. The hepatoprotective action is likely related to its potent antioxidative activity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Clitoria/química , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Substâncias Protetoras/uso terapêutico , Acetaminofen , Animais , Antioxidantes/metabolismo , Bilirrubina/sangue , Biomarcadores/metabolismo , Compostos de Bifenilo/metabolismo , Hidroxitolueno Butilado/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Flavonoides/análise , Sequestradores de Radicais Livres/metabolismo , Concentração Inibidora 50 , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Masculino , Camundongos , Fenóis/análise , Fitoterapia , Picratos/metabolismo , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Padrões de Referência
19.
Int J Biol Macromol ; 49(4): 466-70, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21664928

RESUMO

The extraction conditions of polysaccharides from Plantago asiatica L. seeds were investigated. Four parameters affecting the polysaccharides extraction, extraction times, water to sample, extraction temperature and single extraction time, were determined by orthogonal experiments. Under the optimized conditions, the polysaccharides yield of P. asiatica L. seeds was 2.467%. The antioxidant activities of the polysaccharides were investigated. The reducing power of the polysaccharides was dose dependent, and the reducing capacity of the polysaccharides was inferior to butylated hydroxytoluene, which is known to be a strong reducing agent. The scavenging rates of the polysaccharides on superoxide and 1,1-diphenyl-2-picrylhydrazyl radicals were 79.7% and 81.4%, at polysaccharides concentration of 0.75 mg/mL, respectively, a scavenging rates approximately similar to that of 0.75 mg/mL ascorbic acid (83.5% and 85.1%, respectively). Furthermore, it exhibited a moderate concentration-dependent ABTS radical scavenging activity, ferrous ion chelating potency and H(2)O(2) scavenging activity. The data obtained in the in vitro models clearly establish the antioxidant potency of the polysaccharides extracted from Semen Plantaginis.


Assuntos
Antioxidantes/farmacologia , Plantago/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Sementes/química , Ácido Ascórbico/farmacologia , Benzotiazóis/metabolismo , Compostos de Bifenilo/metabolismo , Hidroxitolueno Butilado/metabolismo , Quelantes/farmacologia , Fracionamento Químico , Ácido Edético/farmacologia , Sequestradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/metabolismo , Oxirredução/efeitos dos fármacos , Picratos/metabolismo , Ácidos Sulfônicos/metabolismo , Superóxidos/metabolismo
20.
J Microbiol Biotechnol ; 21(5): 494-502, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21617346

RESUMO

Coenzyme Q10 (CoQ10) is a widely used supplement in heart diseases treatment or antioxidative dietary. The microbial production of CoQ10 was enhanced by addition of solanesol and novel precursors recovered from waste tobacco. The novel precursors were separated by silica gel and identified as alpha-linolenic acid (LNA) and butylated hydroxytoluene (BHT) based on the effect on CoQ10 production and GC-MS. The effects of novel precursors on CoQ10 production by Sphingomonas sp. ZUTE03 were further evaluated in a two-phase conversion system. The precursor's combination of solanesol (70 mg/l) with BHT (30 mg/l) showed the best effect on the improvement of CoQ10 yield. A maximal CoQ10 productivity (9.5 mg l-1 h-1) was achieved after 8 h conversion, with a molar conversion rate of 92.6% and 92.4% on BHT and solanesol, respectively. The novel precursors, BHT and LNA in crude extracts from waste tobacco leaves, might become potential candidates for application in the industrial production of CoQ10 by microbes.


Assuntos
/química , Extratos Vegetais/metabolismo , Sphingomonas/metabolismo , Ubiquinona/análogos & derivados , Hidroxitolueno Butilado/análise , Hidroxitolueno Butilado/isolamento & purificação , Hidroxitolueno Butilado/metabolismo , Microbiologia Industrial , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Eliminação de Resíduos , Terpenos/análise , Terpenos/isolamento & purificação , Terpenos/metabolismo , Ubiquinona/metabolismo , Ácido alfa-Linolênico/análise , Ácido alfa-Linolênico/isolamento & purificação , Ácido alfa-Linolênico/metabolismo
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