Introduction and chemical analysis of Grindelia Squarrosa (Purch) Dunal in Vytautas Magnus univesity

Abstract

At present and in the future it is necessary to enrich the assortment of the cultivated medicinal plants. Species of medicinal (aromatic) plants have been introduced ex~situ~in the medicinal plants collection~of Sector of Medicinal Plants~at Kaunas Botanical Garden of Vytautas Magnus University~since 1924 for this purpose. Biodiversity of plant resources, scarce information on bioactive compounds and their properties in many species, including those growing in Lithuania, as well as increasing demand for naturalness of~herbal medicines and food were the main motivation aspects of the present study. Medicinal (aromatic) plants, their raw materials and biologically active compounds were investigated. Grindelia is a famous genus of medicinal plant; the species robusta and squarrosa are, in particular, the most used in medicinal industry. The phenolic compounds, flavonoïds in particular, have a function in the medicinal property of Grindelia. But the concentrations of these products are changing between the different periods of development of the plant. The target of this experiment is to analyze the difference of the concentration of phenolic compounds, flavonoïds and radical scavenging activity between growing periods, budding period, start blooming, full blooming and end of blooming period. Grindelia squarrosa (Purch) Dunal was collected and air-dried at Kaunas Botanical Garden of Vytautas Magnus University. The plant was crush and 0,5g were extracted with 20 ml of 75% methanol and shacked during 24h. Spectrophotometry methods were used to find total phenolic compounds (using Folin-Ciocalteu Reagent), the content of flavonoïds and radical scavenging activity (using DPPH as a radical reagent). The results are showing that the radical scavenging activity is less important than the total phenolic compounds; we can explain this result because all the phenolic compounds don’t have abilities to reduce DDPH. [...]