RESUMO
This report presents evidence that the following Solanum steroids: solasodine, diosgenin and solanine interact with human erythrocytes and molecular models of their membranes as follows: a) X-ray diffraction studies showed that the compounds at low molar ratios (0.1-10.0mol%) induced increasing structural perturbation to dimyristoylphosphatidylcholine bilayers and to a considerable lower extent to those of dimyristoylphosphatidylethanolamine; b) differential scanning calorimetry data showed that the compounds were able to alter the cooperativity of dimyristoylphosphatidylcholine, dimyristoylphosphatidylethanolamine and dimyristoylphosphatidylserine phase transitions in a concentration-dependent manner; c) in the presence of steroids, the fluorescence of Merocyanine 540 incorporated to the membranes decreased suggesting a fluidization of the lipid system; d) scanning electron microscopy observations showed that all steroids altered the normal shape of human erythrocytes inducing mainly echinocytosis, characterized by the formation of blebs in their surfaces, an indication that their molecules are located into the outer monolayer of the erythrocyte membrane.
Assuntos
Diosgenina/química , Membrana Eritrocítica/química , Bicamadas Lipídicas/química , Alcaloides de Solanáceas/química , Solanina/química , Varredura Diferencial de Calorimetria , Dimiristoilfosfatidilcolina/química , Diosgenina/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Corantes Fluorescentes/química , Humanos , Microscopia Eletrônica de Varredura , Transição de Fase/efeitos dos fármacos , Fosfatidiletanolaminas/química , Fosfatidilserinas/química , Pirimidinonas/química , Espalhamento a Baixo Ângulo , Alcaloides de Solanáceas/farmacologia , Solanina/farmacologia , Difração de Raios XRESUMO
Glycoalkaloids are toxic secondary plant metabolites found in potatoes, tomatoes, and eggplants and they are considered potential precursors of steroids for applications in bionanotechnology. In this work, we make use of a new model chemistry within density functional theory, which is called CHIH-DFT, to calculate the molecular structure of gamma-solanine, as well to predict its infrared (IR) and ultraviolet (UV-vis) spectra, and some other electronic parameters.
Assuntos
Modelos Moleculares , Solanina/química , Biotecnologia , Estrutura Molecular , Nanotecnologia , Plantas Comestíveis/química , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
Steroidal glycoalkaloids of many Solanum species have recognized biological activities, especially those containing the glycosyl moiety alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-D-glucopyranose (chacotriose) whose peracetate is here synthesized and characterized by complete 1H and 13C NMR assignment.