Antioxidant and Cytotoxic Properties of Black Turmeric (Curcuma Caesia Roxb.) Rhizome Extract

Abstract

The rhizomes of Curcuma caesia have got wide range of attention on various antipyretic, analgesic, antimutagenic, neuropharmacological, antibacterial and antifungal pharmacological activities. It is well known for its peculiar characteristics other than yellow turmeric. With the increasing trend on natural products in modern phytomedicines, the antioxidant and cytotoxic activities of Curcuma caesia Roxb. rhizome fractions were evaluated. The DCM fraction showed highest activity with DPPH assay (78.17%) comparable to the ascorbic acid (88.01%) at 100µg/ml concentration with IC50 42.72±1.06 µg/ml for DCM fraction followed by MEFCC (109.25±3.4 µg/ml) and HEFCC (214.87±0.78 µg/ml) respectively. DCM fraction exhibited more potent antioxidant, subjected to purify active compound with Sephadex LH-20 column chromatography and thin layer Chromatography (TLC), revealed different phytochemical compound with different Rf values ranging from 0.21 to 0.56. Moreover, based on antioxidant activity, the rhizome fractions were subjected to their cytotoxic properties against brine shrimp napaulii. The highest degree of lethality was observed in Methanol fraction (LC50 37.12 µg/ml). Lower the LC50 xiii

11.42 µg/ml), while low at DCM fraction (LC50 value of extract, higher its cytotoxic effect. As all the extract fractions in both the assay were found to be react in dose dependent manner. The results thus obtained in the present study indicated that Curcuma caesia Roxb. rhizome is a rich source of phytochemicals. This could justify the use of plant species in traditional medicines for the treatment of various ailments.