Thanks to good tolerability and fewer side effects that natural compounds are considered an effective
therapy for the treatment of various diseases. In particular, the use of naturally-derived products
containing antioxidants is of great interest today. In this study, two species of plants including Ananas
comosus (L.) Merr. and Cassia alata L. were evaluated in vitro antioxidant activities. The results
indicated that the ethanolic extract from the roots of Cassia alata L. gave good antioxidant activity on
both DPPH and ABTS●+ testing methods with the EC50 values of 26,76 ± 0,43 and 217,12 ± 9,89 μg/mL,
respectively; 157,24 ± 1,07 and 1290,97 ± 34,96 μg/mL corresponding to the EC50 values of the
ethanolic extract of Ananas comosus (L.) Merr. leaves. In addition, total polyphenol and flavonoid
contents of Cassia alata L. extract were determined 105,67 ± 8,68 mg GAE/g and 62,90 ± 4,89 mg
QE/g. Likewisely, the extract of Ananas comosus L. had total polyphenol and flavonoid content of 49,79
± 2,01 mg GAE/g and 39,49 ± 3,05 mg QE/g, respectively.