RESUMO
Previous phytochemical investigations have revealed the presence of a variety of compounds such as pyrrolidine derivatives, flavonoids, and megastigmanes in Egyptian plants. Onopordum alexandrinum has been traditionally used by the natives for treatment of skin cancers and leprosy. In this paper the isolation of four new sesquiterpene-amino acid conjugates, onopornoids A-D (1-4), i.e., three elemanes and one germacrane, and a new acylated flavonoid glucoside (5) along with nine known compounds (6-14) from the whole aerial parts of the title plant is discussed. The structures were elucidated based on chemical and spectroscopic/spectrometric data.
Assuntos
Aminoácidos/análise , Flavonoides/isolamento & purificação , Glucosídeos/análise , Onopordum/química , Sesquiterpenos/isolamento & purificação , Aminoácidos/química , Egito , Flavonoides/química , Glucosídeos/química , Estrutura Molecular , Compostos Fitoquímicos , Sesquiterpenos/químicaRESUMO
Deep eutectic solvents (DES) and aqueous glycerol were proposed as green alternatives to conventional solvents for the extraction of polyphenols from grapefruit peels. In order to increase the extraction kinetics and yields of polyphenols, high voltage electrical discharges (HVED) were used as a pre-treatment technology (energy varied between 7.27 and 218â¯kJ/kg). Results showed that the HVED energy input can be reduced, when the subsequent solid-liquid extraction was performed in 20% (w/v) aqueous glycerol or in DES (lactic acid: glucose) instead of water. The addition of glycerol has reduced the energy of the pre-treatment by 6 times. The same diffusivity of polyphenols (4â¯×â¯10-11â¯m2/s) was obtained in water from HVED pre-treated peels at 218â¯kJ/kg and in aqueous glycerol from pre-treated peels at 36â¯kJ/kg. The solubility of naringin, the main flavonoid compound of grapefruit peels in the solvents, was investigated through a theoretical modelling of its Hansen solubility parameters.
Assuntos
Citrus paradisi/química , Glicerol/química , Polifenóis/isolamento & purificação , Solventes/química , Cromatografia Líquida de Alta Pressão , Citrus paradisi/metabolismo , Eletricidade , Flavanonas/química , Flavonoides/química , Glucose/química , Ácido Láctico/química , Extração Líquido-Líquido , Polifenóis/análise , Solubilidade , Água/químicaRESUMO
The genus Symplocos has been reviewed for its chemical constituents and biological activities including traditional importance of some common species. The plants of this genus contain terpenoids, flavonoids, lignans, phenols, steroids, alkaloids, and iridoids. Terpenoids are the major constituents within the genus Symplocos and most of them exhibit antiproliferative effects. Some phenolic glycoside derivatives showed inhibitory activity against snake-venom phosphodiesterase I and human nucleotide pyrophosphatase phosphodiesterase I. The members of genus Symplocos are well known for their traditional uses in the treatment of various diseases like leprosy, gynecological disorders, ulcers, leucorrhea, menorrhagia, malaria, and tumefaction. The aim of the present paper is to review the comprehensive knowledge of the plants of this genus including the traditional uses, chemistry, and pharmacology.