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1.
Int J Biol Macromol ; 146: 730-738, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31739026

RESUMEN

Carboxymethyl cellulose (CMC)-based films were developed by incorporating green coffee oil (GCO) obtained by cold pressing and hydroalcoholic extracts of its residues. The effect of cake (CE) and sediment extracts (SE) in different proportions (20-40%) and GCO on chemical, morphological, physical, mechanical, optical, and antioxidant properties of the films was investigated. Eight fatty acids and four major phenolic compounds were identified by High-Resolution Direct-Infusion Mass Spectrometry in GCO and residue extracts. FTIR indicated interactions among CMC, phenolic compounds, and fatty acids. Films enriched with residue extracts presented heterogeneous microstructure. The tensile strength of the films decreased from 58 to 3 MPa with the extracts concentration, while elongation increased from 28 to 156% (p < 0.05). The water vapor permeability (averaging 3.94 × 10-8 g mm/cm2 h Pa) was not significantly affected by the extracts and GCO. The surface color was influenced by the type and concentration of extracts (p < 0.05), the film with SE40% had remarkable UV-vis barrier properties. The incorporation of GCO residue extracts imparted high antioxidant capacity to the CMC-based films, especially with CE40% (643.8 µmol Trolox eq./g dried film; 51.3 mg GAE/g dried film). General observations indicated the potential of these films, mainly the ones containing CE, like active packaging material for food applications.


Asunto(s)
Carboximetilcelulosa de Sodio/química , Coffea/química , Café/química , Antioxidantes/análisis , Fenómenos Químicos , Cromanos/química , Color , Embalaje de Alimentos , Permeabilidad , Fenol/análisis , Extractos Vegetales/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Vapor , Resistencia a la Tracción
2.
J Nat Prod ; 67(11): 1882-5, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15568781

RESUMEN

As part of our study on bioactive agents from Brazilian rainforest plants, two new glucoalkaloids, 3,4-dehydro-strictosidine (1) and 3,4-dehydro-strictosidinic acid (2), were isolated from Chimarrhis turbinata, along with seven known glucoalkaloids, cordifoline (3), strictosidinic acid (4), strictosidine (5), 5 alpha-carboxystrictosidine (6), turbinatine (7), desoxycordifoline (8), and harman-3-carboxylic acid (9). The structures of the new alkaloids were established on the basis of comprehensive spectral analysis, mainly 1D and 2D NMR experiments, as well as high-resolution HRESIMS. Alkaloid 3 showed strong free-radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) as well as pronounced antioxidant activity evidenced by redox properties measured by ElCD-HPLC. Additionally, alkaloids 1-9 were submitted to TLC screening for acetylcholinesterase inhibitors. Both 7 and 8 were shown to be moderate acetylcholinesterase inhibitors at a concentration of 0.1 and 1.0 microM, respectively. In an in vitro rat brain assay, 7 showed moderate activity (IC(50) 1.86 microM), compared to the standard compound, galanthamine (IC(50) 0.92 microM).


Asunto(s)
Antioxidantes/aislamiento & purificación , Inhibidores de la Colinesterasa/aislamiento & purificación , Alcaloides Indólicos/aislamiento & purificación , Rubiaceae/química , Animales , Antioxidantes/química , Antioxidantes/farmacología , Encéfalo/metabolismo , Brasil , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacología , Concentración 50 Inhibidora , Estructura Molecular , Oxidación-Reducción , Ratas
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