Electronic Theses and Dissertation

enelitian ini dilakukan untuk mengetahui aktivitas antioksidan dari ekstrak metanol, nheksan, etilasetat, dan residu metanol, fraksi gabungan serta subfraksi gabungan dari hasil
pemisahan kulit batang Cassia siamea. Berat ekstrak metanol, n-heksana, etilasetat, dan
metanol partisi kulit batang Cassia siamea diperoleh dari proses maserasi adalah 344,0375;
72,8031; 27,3423; dan 39,21 (g) . Pengujian aktivitas antioksidan dilakukan dengan
menggunakan metode 1 diphenyl-2-pychrilhidrazil (DPPH). Nilai inhibitory concentration
(IC50) yang diperoleh adalah sebesar 41,37; 97,26; 20; dan 43 (ppm) untuk ekstrak metanol, nheksan, etilasetat, dan residu metanol secara berturut-turut. Ekstrak etilasetat kulit batang
Cassia siamea kemudian diisolasi menggunakan kromatografi cair vakum sehingga diperoleh
4 fraksi berdasarkan kemiripan pola nodanya. Setiap fraksi diuji aktivitas antioksidan sehingga
diperoleh nilai IC50 yaitu 17,69; 37,40; 48,22; dan 58,56 (ppm) untuk CSE A, CSE B, CSE C,
dan CSE D secara berturut-turut. Fraksi CSE A sebagai fraksi yang paling aktif selanjutnya
disolasi kembali menggunakan kromatografi kolom gravitasi dan diperoleh 6 subfraksi
berdasarkan pola nodanya. Setiap subfraksi diuji aktivitas antioksidannya dan diperoleh
subfraksi paling aktif yaitu subfraksi F.C dengan nilai IC50 16, 43 ppm. Ekstrak CSE, fraksi
C.A, dan subfraksi C.A.3 dianalisis menggunakan gas chromatography – mass
spectrofotometry dan diperoleh senyawa 1H-2-Benzopyran-1-one, 3,4-dihydro-3,8- dihydroxy-3-
methyl yang merupakan golongan senyawa kumarin.

This research was conducted to determine the antioxidant activity of methanol extract, nhexane, ethylacetate, and methanol residue, combined fractions, and combined sub-fractions from the separation of the bark of Cassia siamea. The weight of methanol extract, n-hexane, ethylacetate, and methanol partition of Cassia siamea stem bark obtained from the maceration process is 344,0375; 72,8031; 27,3423; dan 39,21 (g), Testing of antioxidant activity was carried out using the 1,1-diphenyl-2-pychrilhidrazil (DPPH) method. The inhibitory concentration (IC50) value obtained was 41.37; 97.26; 20; and 43 (ppm) for methanol extract, n-hexane, ethylacetate, and methanol residue, respectively. The ethylacetate extract from the bark of Cassia siamea was then isolated using vacuum liquid chromatography to obtain four fractions based on the similarity of the stain patterns. Each fraction was tested for antioxidant activity so that the IC50 values were 17.69, 37.40, 48.22, and 58.56 (ppm) for CSE A, CSE B, CSE C, and CSE D, respectively. The CSE A fraction, as the most active fraction, was further isolated using gravity column chromatography, and six sub-fractions were obtained based on the stain pattern. Each sub-fraction was tested for its antioxidant activity, and the most active sub-fraction was obtained, namely the F.C. sub-fraction with an IC50 value of 16.43 ppm. CSE extract, C.A fraction, and C.A.3 subfraction were analyzed using gas chromatography – mass spectrophotometry and obtained compounds 1H-2-Benzopyran-1-one, 3,4-dihydro-3,8- dihydroxy-3-methyl which are coumarin compounds.