Résumé
Acetylcholinesterase (AChE), hydrolyzes acetylcholine to choline and acetate, thereby terminating this neurotransmitter effect at cholinergic synapses. Therefore, AChE inhibition is used for counterbalance the cholinergic deficit in Alzheimer's disease (AD) patients. In the present work, in order to find new plant acetylcholinesterase inhibitors, the hydroalcoholic extracts from seventeen medicinal plant species were screened for their acetylcholinesterase inhibition activity, as well as total phenolic (TPC) and flavonoids contents (TFC) and antioxidant activity using ORAC (Oxygen Radical Absorbance Capacity) assay, and their ability to inhibit lipid peroxidation. The results revealed that Rumex acetosa, Taraxacum officinale and Hypericum perforatum extracts possessing the highest TPC and TFC, were the most effective in terms of ORAC antioxidant activity, and acetylcholinesterase inhibition, in addition to their ability to inhibit liposomes peroxidation, suggesting that those plant species may provide a substantial source of secondary metabolites, which act as natural antioxidants and acetylcholinesterase inhibitors, and may be beneficial in the treatment of AD.
La acetilcolinesterasa (AChE) hidroliza la acetilcolina se hidroliza en colina y acetato, terminando así este efecto neurotransmisor en las sinapsis colinérgicas. Por lo tanto, la inhibición de la AChE se utiliza para contrarrestar el déficit colinérgico en pacientes con enfermedad de Alzheimer (EA). En el presente trabajo, con el fin de encontrar nuevos inhibidores de la acetilcolinesterasa vegetal, se analizaron los extractos hidroalcohólicos de diecisiete especies de plantas medicinales para determinar su actividad inhibidora de la acetilcolinesterasa, así como el contenido total de fenólicos (TPC) y flavonoides (TFC) y la actividad antioxidante utilizando ORAC (Capacidad de absorbancia de radicales de oxígeno) y su capacidad para inhibir la peroxidación de lípidos. Los resultados revelaron que los extractos de Rumexacetosa, Taraxacum officinale e Hypericum perforatum que poseen los más altos TPC y TFC, fueron los más efectivos en términos de actividad antioxidante ORAC e inhibición de acetilcolinesterasa, además de su capacidad para inhibir la peroxidación de los liposomas, sugiriendo que esas especies de plantas puede proporcionar una fuente sustancial de metabolitos secundarios, que actúan como antioxidantes naturales e inhibidores de la acetilcolinesterasa, y puede ser beneficioso en el tratamiento de la EA.
Sujets)
Plantes médicinales , Acetylcholinesterase , Anticholinestérasiques/composition chimique , Flavonoïdes/composition chimique , Composés Phénoliques , Maladie d'Alzheimer , MarocRésumé
The revival of non-conventional edible plants enables important gains in nutritional, social, cultural, economic, and environmental points of view. Among them, sorrel Rumex acetosa L. has been deemed pleasant by consumers due to its acid taste. As we do not have a lot of phytotechnical andnutritional information about this plant, the objective was to assess the influence of different spacing sets and cattle manure dosages on their physical-chemical characteristics and bioactive compounds content with antioxidant action. Randomized blocks with four repetitions was chosen as experimental design, using ascheme of subdivided plots, with five dosages of weather-beaten cattle manure in the plots and two sets of spacing in the subplots. Data was submitted to a variance analysis with two factors (two-way ANOVA). It was not verified any significant effect (P>0.05) in the interaction Dosage x Spacing. Fertilization dosages and spacing sets did not have any effect on color and total soluble solids average contents, humidity, titratable acidity, and phenolic compounds. Increasing dosages of organic fertilizer, up to 75 kg ha-1, reduced the plant's pH; above that amount, pH rose. Presence of anthocyanins and vitamin C was not detected. The total carotenoids average content was not influenced by the manure factor, and the plant presented greater total carotenoids content in the smallest spacing. Antioxidant activity [1.0 mg mL-1], although inferior to the standards that were used (BHT, vitamin C and quercetin), was quite representative. A conclusion was reached that fertilizing with weather-beaten cattle manure had an effect only on pH, and cropping spacing had an influence only on carotenoids content. Other phytochemicals and physical-chemical characteristics were not influenced in sorrel plants with different levels of fertilization and sets of spacing.
O resgate das plantas comestíveis não convencionais possibilita ganhos importantes do ponto de vista nutricional, social, cultural, econômico e ambiental. Dentre estas, a azedinha, Rumex acetosa L. tem agradado o consumidor por seu sabor ácido. Como são poucas as informações fitotécnicas e nutricionais sobre esta planta objetivou-se avaliar a influência de diferentes espaçamentos e doses de esterco bovino em suas características físico-químicas e no teor de compostos bioativos com função antioxidante. O delineamento experimental foi em blocos casualizados com quatro repetições, no esquema de parcelas subdivididas, sendo cinco doses de esterco curtido de gado nas parcelas e dois espaçamentos nas subparcelas. Os dados foram submetidos à análise de variância com dois fatores (two-way ANOVA). Não foi constatado efeito significativo (P>0,05) da interação Dose x Espaçamento. As doses de adubação e espaçamentos não afetaram a cor e os teores médios de sólidos solúveis totais, umidade, acidez titulável e compostos fenólicos. Doses crescentes de adubo orgânico, até 75 kg ha-1, reduziram o pH da planta, acima deste valor o pH elevou-se. Não foi detectada a presença de antocianinas e vitamina C. O teor médio de carotenoides totais não foi influenciado pelo fator esterco e no menor espaçamento a planta apresentou maior teor de carotenoides totais. A atividade antioxidante [1,0 mg mL-1], apesar de inferior aos padrões utilizados (BHT, vitamina C e quercetina), foi bastante representativa. Concluiu-se que a adubação com esterco de gado curtido afetou apenas o pH e que o espaçamento de cultivo exerceu influência apenas teor de carotenoides. Os demais fitoquímicos e características físico-químicas não foram influenciadas em plantas de azedinha com diferentes níveis de adubação e de espaçamento