Antioxidant activity, total phenolic and flavonoid content of leave, stem and rhizome of Plagiostachys spp. (Zingiberaceae)

The total phenolic content, total flavonoid content and the antioxidant activity were studied in Plagiostachys breviramosa and P. roseiflora. The objectives of this research are to determine the total phenolic and flavonoid content and antioxidant activity of leave, stem and rhizome of the Plagiostachys breviramosa and P. roseiflora. The total phenolic content was determined according to the Folin-Ciocalteu method while the total flavonoid content of Plagiostachys species used Catechin as the standard. The antioxidant activity, the 2, 2-Diphenyl-l-picryl-hydrazyl radical (DPPH) scavenging method was used. P. breviramosa rhizome showed the highest value of 156.573 ± 2.847b, 150.667 ± 5.044a and 85.860 ± 0.312c for total phenolic content, total flavonoid content and antioxidant activity respectively. Meanwhile, P. breviramosa leave showed the lowest value for total phenolic content, total flavonoid content and antioxidant activity which are 44.950 ± 3.291i½…, 43.000 ± 0.57e and 54.863 ± 0.9798 respectively. As for the P. roseiflora, the total phenolic content showed the highest value 172.000 ± 2.074a in leave sample while the lowest value, 7.240 ± 1.356f in stem sample. The total flavonoid content was lowest in stem of P. roseiflora, 6.667 ± 0.882f while P. roseiflora rhizome has the highest value which is 137.667 ± 0.882b. However, the highest value of antioxidant activity of P. roseiflora showed in the rhizome part which is 88.290 ± 1.091 f while the leave part has the lowest value which is 56.040 ± 0.156d