ISOLASI SENYAWA TERPENOID EKSTRAK ETIL ASETAT KULIT AKAR BIDURI (CALOTROPIS GIGANTEA)

ABSTRAKIsolasi senyawa terpenoid dari ekstrak etil asetat kulit akar biduri (Calotropis gigantea) telah dilakukan. Kulit akar C. gigantea dimaserasi menggunakan pelarut metanol, kemudian dipartisi menggunakan pelarut n-heksana, dan etil asetat, sehingga diperoleh ekstrak pekat sebanyak 66,18, 20,45, dan 73,60 gram. Ekstrak etil asetat diisolasi menggunakan metode Kromatografi Kolom Cair Vakum (KKCV) sehingga diperoleh 5 fraksi gabungan, yaitu Fraksi A (0,25 g), B (0,62 g), C (0,30 g), D (2,75 g) dan E (5,80 g). Fraksi C direkromatografi menggunakan kromatografi kolom gravitasi menghasilkan 40 fraksi. Hasil uji fitokimia subfraksi C2 menggandung senyawa golongan triterpenoid dan karakterisasi menggunakan spektrometri FT-IR menunjukkan adanya gugus C-H, C=O, C=C, dan C-O (ester). Berdasarkan data spektrometri massa, diduga subfraksi C2 mengandung senyawa tarakseril asetat.Kata Kunci : Calotropis gigantea, tarakseril asetat, triterpenoid.ABSTRACTIsolation of terpenoid compound from ethyl acetate of Calotropis gigantea root bark. The root bark of C. gigantea was macerated using methanol solvent, then partitioned with n-hexane, and ethyl acetate, so obtained concentrated extracts of 66.18, 20.45, and 73.60 g. The ethyl acetate extract was isolated by Vacuum Column Chromatography method (VCC) so that obtained 5 fractions of combined, Fraction A (0.25 g), B (0.62 g), C (0.30 g), D (2.75 g) and E (5.80 g). Fraction C was recromatographed by gravity column chromatography obtained 40 fractions. The result of phytochemical test of subfraction C2 contains triterpene compound then characterized by FT-IR spectrometry showed the presence of C-H, C=O, C=C, and C-O (ester) groups. According to the characterization with mass spectrometry data, C2 subfraction expected have contained taraxeryl acetate compound.Keyword : Calotropis gigantea, taraxeryl acetate, triterpene.

Antiproliferative Activity of Triterpenoid and Steroid Compounds from Ethyl Acetate Extract of Calotropis gigantea Root Bark against P388 Murine Leukemia Cell Lines

Calotropis gigantea has been known to produce bioactive secondary metabolites with antiproliferative activities against cancer cells. Herein, we extracted the secondary metabolites using ethyl acetate from its root bark and further tested its antiproliferative activities against P388 murine leukemia cell lines. The subfractions from the ethyl acetate extract was obtained from Vacuum Liquid Column Chromatography (VLCC), and followed by Gravity Column Chromatography (GCC). The subfraction C2 and D1 were identified to contain triterpenoids and steroids with the most potent cytotoxicity against Brine Shrimp Lethality Test (BSLT). A 3-(4,5-dimethylthiazol-2-yl) -2-5 diphenyl tetrazolium bromide (MTT) assay suggested that ethyl acetate extract has the highest antiproliferative activities against P388 murine leukemia cell lines (IC50 = 21.79 μg/mL), as opposed to subfraction C2 (IC50 = 50.64 µg/mL) and subfraction D1 (IC50 = 49.33 µg/mL). The compound identified in subfraction C2 and D1 are taraxerol acetate and calotropone, respectively. Though taraxerol acetate and calotropone were active in inhibiting the leukemic cell lines, their IC50s were lower than the ethyl acetate extract, which is probably due to the synergism of the secondary metabolites