Influence Of The Vegetative State And Part Of The Plant On The Antioxidant Activity Of Plantago Tomentosa (llantén) From Northeast Of Argentina

RICCIARDI GABRIELA; MATIAS DAMIAN DUQUE DE ARCE; JUAN JOSE RUIZ DIAZ; OJEDA GONZALO; EDUARDO SANTIAGO DELLACASA ; TORRES ANA MARIA

Mar del Plata

Congreso; LI reunión anual de la asociación Argentina de Farmacología Experimental; 2019

Plantago tomentosa Lam. subesp. napiformis Rahn (Rahn) is an herb frequently found in Corrientes (Northeast of Argentina), but there is scarce information related to its chemical and biological activities. The abundance of this species and its traditional use as medicinal plant (digestive, antiulcer and healing), justifies to study more in deep its phytochemistry. In order to evaluate the phytochemistry and antioxidant properties, plant material was collected at two vegetative stages: spring (Sp, flowering stage) being samples divided in roots (R), leaves (L) and flowers (F). The second colleect was performed on summer (Su) where flowers were absent. Extracts of different polarity [aqueous (A), ethanolic (E) and hexanic (H)] were obtained by maceration. Total flavonoids (AlCl3), phenols (Folin-Ciocalteau) and tannins (vainillin-HCl) were evaluated. The antioxidant capacity was studied by free radical scavenging using DPPH (2,2-diphenyl-1-picrylhydrazyl) and by the oxide-reduction ability using potassium ferricyanide (FRAP). The antioxidant activity found was like that of gallic acid for all the ethanolic extracts from Sp samples, while only L ethanolic extract from Su showed similar activity. By FRAP, ethanolic extract of L from Sp and Su presented the highest oxide-reduction capacity (17.7 and 16.9 mg/g extract, respectively), while the other extracts (different organs and polarity) did not show significant antioxidant activity. Quantitation of flavonoids showed that L and F ethanolic extracts presented the main levels (488.2 and 238.2 mg/g, respectively) in Sp, while for Su the value was 167.6 mg/g in L. Phenols levels increased in the ethanolic extracts: 193 mg/g in L and 193.3 mg/g in F at Sp compared to 162,7 mg/g extract in L for Su. Tannins predominated in Su ethanolic extracts of L and R (212,2 and 292,2 mg/g). Results indicated P. tomentosa possess promissory antioxidant activity depending on the growth state and part of plant considered.