#TITLE_ALTERNATIVE#

• Main Author: SISWANTO NUR SIDIK (NIM 10703012), HERI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/8109
• Institution: Institut Teknologi Bandung

Phalerin is an isolat from fruit of mahkota dewa {Phaleria macrocarpa (Scheff.) Boerl.}, which showed anti-inflammatory activity. Biodistribution study in animal for knowing phalerin accumulation in organs can be performed by labeling of phalerin by radionuclide Iodinium-131. Subtitution of radionuclide at nonappropriate atoms of molecule can change the molecular structure and electronic characteristic, thus physicochemical properties related to biology interaction in the body will be different. The present study was designed to observe the substitution effect of radionuclide Iodinium-131 on conformation, electronic properties, and physicochemical properties of phalerin molecule using molecular modeling approach. Parameters of molecular orbital energy, atom charge, electron density, and electrostatic potential were used to analysize molecular reactivity of radionuclide Iodinium-131 labeled phalerin. The structural similarity of phalerin labeled by Iodinium-131 with parent molecule defined by root-mean-square (rms) of bond distance, bond angle, and torsion. Computational results showed that the most negative atom charge that can be replaced by radionuclide Iodinium-131 are C-17 (-0.219), C-15 (-0.71) and C-4 (-0.149). Phalerin labeled by radionuclide Iodinium-131 on C-17 has the most minimum conformation change that can be seen by overlay result and rootmean-square for bond distance (0.00208), bond angle (0.4185), and torsion (2.9074). Thus, phalerin labeled by radionuclide Iodinium-131 on C-17 showed the most similarity with the parent molecule compared to phalerin labeled on the other atoms.