Hanna Sari Widya Kusuma2,Hayatun Nufus2,Seila Arumwardana2,Annisa Amalia2, Rizal Rizal2
1Faculty of Medicine, Maranatha Christian University, Jl. Prof drg. Suria Sumantri No.65, Bandung 40164, West Java, Indonesia
2Aretha Medika Utama, Biomolecular and Biomedical Research Center, Jl Babakan Jeruk 2, No. 9, Bandung 40163, West Java, Indonesia
3Research Center for Chemistry, Indonesian Institute of Sciences, Serpong, Indonesia
Abstract
Antioxidant agent can eliminate the free radicals due to oxidative stress that has been reported as the main cause of diabetes mellitus. This study evaluated the effect of Curcuma longa rhizomes and its compounds curcumin and bisdemethoxycurcumin as antioxidants and antidiabetic activity. The phytochemical assay was performed with modified Farnsworth method. Quantitative curcumin, bisdemethoxycurcumin and curcumol of C. longa extract (CLE) were evaluated using HPLC. The antioxidant assay was performed with 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzo thiazoline-6-sulfonate acid) (ABTS) and Ferric Reducing Antioxidant Power (FRAP) assay. Antidiabetic properties were measured by inhibitory activity of α-, β-glucosidase, and α-amylase. This study suggested that CLE has terpenoids in high level. Based on HPLC test, CLE contained curcumin (16.92%), curcumol (15.51%), and bisdemethoxycurcumin (5.27%). Bisdemethoxycurcumin has DPPH scavenging activity (IC50= 64.94±2.44 µg/ml), curcumin has the highest activity (IC50=0.92±0.03 µg/ml) in ABTS assay, while CLE has the highest activity in FRAP assay (IC50=311.10 µM Fe(II)/µg) in the highest concentration (250.00 µg/ml). In antidiabetic assay, bisdemethoxycurcumin has the highest in α-glucosidase and α-amylase inhibitory activity (IC50=3.76±0.33 µg/ml; 1.79± 0.15 µg/ml), while in β-glucosidase inhibitory activity curcumin has the highest activity (IC50=1.03±0.03 µg/ml). CLE and its compounds possess antioxidants and antidiabetic activities.
