Antioxidant activities of the constituents of Picris echoides

Abstract

Some flavonoids with antioxidant properties from the aerial parts of the plant species Picris echoides (family Asteraceae) were identified. Upon chromatography, the ethyl acetate extract afforded flavonoids, such as flavone apigenin (1) and its glucoside, cosmosiin (2), as well as common plant constituents from this family, flavonol galetin (3 3,4?,5,6,7-pentahydroxyflavone) and 4,4?,6,7-tetrahydroxyaurone (4). The structure of the aurone 4 has not been described so far in the literature and presented a very rare type of aurone skeleton. The structures of the isolated compounds were determined by interpretation of their physical and spectral data. The antioxidant activities of different extracts from Picris echoides were measured by the Schaal oven test at 60 ?C and by the Rancimat method at 100 ?C.Water/ethanol extracts (2:8, v/v), in concentrations of 0.02 and 0.05 %, showed lower activity than commercial tocopherol (Tch). On the contrary, the purified ethyl acetate extracts showed a strong concentration-dependent antioxidant effect. The investigation demonstrated that galetin was the main flavonol from this origin. According to the results of the two methods, galetin (3) showed a two-fold better activity than didTch and a lower activity than did butylated hydroxyanisole (BHA). The aurone 4 exhibited significantly lower antioxidant activity than did galetin at the same concentration level. Thus, the plant species P. echoides is a new and favorable source of natural lipid antioxidants.

Altered leaf colour is associated with increased superoxide‐scavenging activity in aureusidin‐producing transgenic plants

“…Aurone formation has been reported for several edible Asteraceae and Amaranthaceae (Ferreira et al. , 2004; General books LLC, 2010; Milovanovic et al. , 2002).…”

“…Although commercial interests in aurones are currently limited to how these compounds affect flower colour, their antioxidant activities suggest future medicinal applications as well (Boumendjel, 2003; Detsi et al. , 2009; Milovanovic et al. , 2002).…”

“…The first report on aurone‐containing foods relates to the aromatic herb bristly ox‐tongue ( Picris echoides ), which is used in traditional medicine for the treatment of ingestion and intestinal parasites (Milovanovic et al. , 2002).…”

“…Although commercial interests in aurones are currently limited to how these compounds affect flower colour, their antioxidant activities suggest future medicinal applications as well (Boumendjel, 2003;Detsi et al, 2009;Milovanovic et al, 2002). Indeed, the 3¢,4¢,6,7 tetrahydroxyaurone from Devil's Beggarticks (Bidens frondosa) is more effective at scavenging free radicals than vitamin C, vitamin E and resveratrol (Venkateswarlu et al, 2004).…”

Qualitative Assessment of Chemical Constituents of Picris Babylonica

“…[2][3] Many species of picris investigated previously and revealed that they contain many and various types of constituents like sesquiterpenes, phenolic compounds, flavonoids and terpenoids. [2][3][4][5][6][7][8] Picris babylonica is distributed in many parts of Saudi Arabia. According the recent literature review using most relevant resources, P. babylonica was investigated for its…”