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1.
Sci Total Environ ; 681: 488-496, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31121399

RESUMO

The polycyclic musk galaxolide (HHCB) is widely used as fragrances in personal care products (PCPs) and has been detected in various environmental media. There is an urgent need to derive aquatic life criteria (ALC) of HHCB for the protection of aquatic organisms. Toxicity tests with 8 Chinese resident aquatic organisms from 3 phyla and 8 families were conducted, and three methods were used for deriving the ALC. A criterion maximum concentration (CMC) of 8.33 µg/L and a criterion continuous concentration (CCC) of 2.20 µg/L were derived according to the USEPA guidelines. The acute predicted no effect concentrations (PNECs) values derived by log-normal species sensitivity distribution (SSD) and log-logistic SSD method were 77.41 and 66.47 µg/L, respectively. In addition, a significant sensitivity difference was observed between the planktonic crustacean and benthic crustacean, and there was no significant difference (p > 0.05) among SSDs based on resident and non-resident species. A comparison of chronic SSDs between HHCB, tonalide (AHTN) and musk ketone (MK) showed that nitro musk (MK) was more toxic to aquatic organisms than polycyclic musks (HHCB and AHTN). Finally, an assessment of risk to aquatic organisms in surface waters and effluents of wastewater treatment plants (WWTPs) worldwide showed that potential risk may exist at several locations. HHCB concentrations in 4.08 and 46.17% of the WWTP effluents in China and 1.71 and 16.13% of the WWTP effluents in other countries exceed the hazard concentration for 5% and 1% aquatic species.


Assuntos
Benzopiranos/toxicidade , Odorantes/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água/normas , Organismos Aquáticos/fisiologia , Benzopiranos/normas , Poluentes Químicos da Água/normas
2.
Pharm Biol ; 53(9): 1339-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25864864

RESUMO

CONTEXT: Brazilin is a major active principle of Caesalpinia sappan L. (Leguminosae or Fabaceae). For industry aspects, brazilin-rich extract (BRE) has been prepared and standardized to contain 39% w/w brazilin. BRE may have more advantages than brazilin in term of a lower-cost production process. OBJECTIVES: To investigate the antioxidant, antibacterial, and anti-inflammatory activities of BRE. MATERIAL AND METHODS: BRE was prepared by a simple one-step purification of the crude ethanol extract of C. sappan heartwood (CSE) using a Diaion® HP-20 column. The antioxidant activities were determined using three methods, including DPPH radical scavenging, reducing power, and ß-carotene bleaching assays, at concentration ranges of 1-10, 10-100, and 10-100 µg/mL, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of BRE (15.6-1000 µg/mL) against Gram-positive and Gram-negative bacteria were determined by the broth microdilution method. Anti-inflammatory activity of BRE (0.1-5 µg/mL) was evaluated as anti-denaturation activity using bovine serum albumin as a substrate. RESULTS AND DISCUSSION: On the basis of ß-carotene bleaching assay, BRE showed antioxidant activity with an EC50 value of 60.5 µg/mL, which was almost equal to that of pure brazilin (52.1 µg/mL). Gram-positive bacteria were more sensitive to all tested samples than Gram-negative bacteria. BRE possessed higher antibacterial activities than CSE, but lower than brazilin. MIC/MBC values of 62.5-125/125 and 250-500/250-500 µg/mL were obtained for BRE against Gram-positive and Gram-negative bacteria, respectively. A low concentration (0.1 µg/mL) of brazilin, BRE, and CSE showed anti-inflammatory activity by inhibiting protein denaturation up to 46.8, 54.1, and 61.9%, respectively.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Benzopiranos/farmacologia , Caesalpinia , Extratos Vegetais/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/normas , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/normas , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/normas , Benzopiranos/química , Benzopiranos/isolamento & purificação , Benzopiranos/normas , Compostos de Bifenilo/química , Caesalpinia/química , Relação Dose-Resposta a Droga , Etanol/química , Bactérias Aeróbias Gram-Negativas/efeitos dos fármacos , Bactérias Aeróbias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Oxirredução , Fitoterapia , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/normas , Plantas Medicinais , Desnaturação Proteica , Soroalbumina Bovina/química , Solventes/química , beta Caroteno/química
3.
Biomed Chromatogr ; 26(6): 775-80, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22031358

RESUMO

A fast, economic, reproducible, accurate, effective, rugged and selective chiral-HPLC method was developed and validated for the enantiomeric resolution of nebivolol enantiomers [(+)-RRRS and (-)-SSSR)] in dosage formulation. The method was rapid as chiral separation occurred within only 12 min. The mobile phase used was n-heptane-ethanol-DEA (85:15:0.1, v/v) at 3.0 mL/min flow-rate with 225 nm detection. The column used was an amylase-based 3-AmyCoat (150 × 46 mm) [tris-(3,5-dimethylphenyl carbamate)]. The capacity factors of (+)-RRRS and (-)-SSSR enantiomers were 7.85 and 10.90 while the separation and resolution factors were 1.39 and 1.83, respectively. The limits of detection and quantitation for (+)-RRRS enantiomer were 4.5 and 10.00 µg/mL, while these values for (-)-SSSR enantiomer were 4.1 and 8.2 µg/mL, respectively. The linearity was observed in the concentrations range of 0.10-1.0 mg/mL for both enantiomers. The π-π interactions, hydrogen bonds, dipole-dipole interactions and steric effects control the chiral resolution of nebivolol enantiomers on the reported chiral column. The reported method can be used for the quality control of nebivolol in pharmaceutical preparations with good economy. In addition, this method can also be used for the analysis of (+)-RRRS and (-)-SSSR) enantiomers in biological and environmental samples.


Assuntos
Benzopiranos/química , Cromatografia Líquida de Alta Pressão/métodos , Etanolaminas/química , Benzopiranos/análise , Benzopiranos/normas , Química Farmacêutica/normas , Estabilidade de Medicamentos , Etanolaminas/análise , Etanolaminas/normas , Limite de Detecção , Modelos Lineares , Nebivolol , Reprodutibilidade dos Testes , Estereoisomerismo
4.
Trends Biotechnol ; 28(6): 300-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20452692

RESUMO

The recent approval of fungal carotenoids as food colorants by the European Union has strengthened the prospects for fungal cell factories for the production of polyketide pigments. Fungal production of colorants has the main advantage of making the manufacturer independent of the seasonal supply of raw materials, thus minimizing batch-to-batch variations. Here, we review the potential of polyketide pigments produced from chemotaxonomically selected non-toxigenic fungal strains (e.g. Penicillium and Epicoccum spp.) to serve as food colorants. We argue that the production of polyketide azaphilone pigments from such potentially safe hosts is advantageous over traditional processes that involve Monascus spp., which risks co-production of the mycotoxin citrinin. Thus, there is tremendous potential for the development of robust fungal production systems for polyketide pigments, both to tailor functionality and to expand the color palette of contemporary natural food colorants.


Assuntos
Benzopiranos/metabolismo , Biotecnologia/métodos , Corantes de Alimentos/metabolismo , Microbiologia de Alimentos , Fungos/metabolismo , Macrolídeos/metabolismo , Pigmentos Biológicos/metabolismo , Benzopiranos/isolamento & purificação , Benzopiranos/normas , Benzopiranos/toxicidade , União Europeia , Corantes de Alimentos/isolamento & purificação , Corantes de Alimentos/normas , Corantes de Alimentos/toxicidade , Humanos , Macrolídeos/isolamento & purificação , Macrolídeos/normas , Macrolídeos/toxicidade , Pigmentos Biológicos/isolamento & purificação , Pigmentos Biológicos/normas , Pigmentos Biológicos/toxicidade
6.
Environ Sci Technol ; 35(21): 4289-94, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11718344

RESUMO

Two-dimensional phase sensitive 13C,1H correlation spectra were applied to the investigation of substructures in size fractions obtained by tangential flow multistage ultrafiltration (MST-UF) of humic substances (HS) Suwannee River Fulvic Acid Reference (HS SR FA) and Suwannee River Humic Acid Reference (HS SR HA), purchased from the International Humic Substances Society (IHSS). After size fractionation with MST-UF the HS samples give well resolved two-dimensional 13C,1H-correlated NMR spectra which offer a great potential for substructure elucidation and even quantification. It is shown that low molecular size lignin moieties undergo demethylation of the methoxy groups, accompanied by removal of the phenylpropane side chains and subsequent reaggregation of the aromatic rings. These findings provide insight into the processes of lignin degradation. Only the fraction >100 kDa contains macromolecules that have spin-spin relaxation times too short for investigations employing NMR multipulse sequences.


Assuntos
Benzopiranos/análise , Água Doce/química , Substâncias Húmicas/análise , Abastecimento de Água/análise , Benzopiranos/normas , Carbono/metabolismo , Substâncias Húmicas/normas , Lignina/química , Lignina/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Poluentes do Solo/análise , Poluentes da Água/análise , Abastecimento de Água/normas
7.
Contraception ; 44(4): 461-72, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1824558

RESUMO

Compound CDRI-85/287: 2-[4-(2-N-piperidinoethoxy) phenyl]-3-phenyl (2H) benzo (b) pyran has been identified as a potent antiimplantation agent in rat. A single oral dose (2.5 mg/kg body weight) of the compound administered on days 1, 2 or 3 of pregnancy or multiple dosing (0.05 mg/kg daily) on days 5-7 postcoitum effectively prevented pregnancy. When administered on days 5-7 postcoitum, it failed to interrupt pregnancy even at 20 mg/kg dose. The compound is a potent antiestrogen, with very weak uterotrophic activity; it does not induce vaginal cornification in immature ovariectomised rat. Also, it is devoid of progestational, antiprogestational, androgenic, antiandrogenic and antigonadotrophic activities. The results suggest that the compound exerts its antiimplantation acivity in rat by virtue of its antiestrogenic activity [corrected].


Assuntos
Benzopiranos/farmacologia , Implantação do Embrião/efeitos dos fármacos , Antagonistas de Estrogênios/farmacologia , Piperidinas/farmacologia , Animais , Benzopiranos/normas , Anticoncepcionais Pós-Coito/farmacologia , Anticoncepcionais Pós-Coito/normas , Relação Dose-Resposta a Droga , Antagonistas de Estrogênios/normas , Feminino , Piperidinas/normas , Gravidez , Coelhos , Ratos , Ratos Endogâmicos
9.
Stain Technol ; 50(2): 115-8, 1975 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-49944

RESUMO

All additives tested (ethyl alcohol, glycerine, chloral hydrate, ethylene and propylene glycol, and citric, malonic and maleic acids) in varying degrees limited the conversion of hematein to insoluble compounds. Peak absorbances increased slightly in hematoxylin solutions containing citric, malonic and maleic acids, but decreased with other additives, and in controls. After four months storage the absorbance in all solutions increased about 50%, acidity increased and staining effectiveness increased.


Assuntos
Alumínio/normas , Benzopiranos/normas , Hematoxilina/normas , Potássio/normas , Coloração e Rotulagem/métodos , Álcoois/farmacologia , Hidrato de Cloral/farmacologia , Citratos/farmacologia , Etilenoglicóis/farmacologia , Glicerol/farmacologia , Iodo , Maleatos/farmacologia , Malonatos/farmacologia , Oxigênio , Propilenoglicóis/farmacologia , Sódio , Soluções , Sulfatos/normas
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