Spectroscopic Characterization and Antibiotic Study of Novel Compound Extracted from Curcuma longa (Turmeric)

Aims: To isolate and investigate the antibacterial potency of novel compound obtained from methanolic extract of Curcuma longa rhizome. Place and Duration of Study: Bio-inorganic and Materials Chemistry Research laboratory, MMAM Campus (Tribhuvan university), Biratnagar, Nepal. The experimental work was done between March 2014 and August 2014. Methodology: The crude methanolic extract was prepared by digesting powdered Curcuma longa rhizome in distilled methanol and chromatographic technique like TLC and column chromatography were applied to isolate the new compound. The structural determination with proposed molecular structure was ascertained by different spectral techniques like IR, 1H NMR and TOF-MS studies and correct stereochemistry was assured by molecular modeling programmed software. The antibacterial potency of the compound was checked by Kirby Bauer paper disc diffusion method, using Mueller-Hinton's nutrient agar media. Results: The spectral studies revealed the presence of a novel compound, structurally different than curcumin, a major constituent of Curcuma longa. Elemental analysis (CHN) suggested it a Sulphur containing supramolecule with molecular formula C69H78N4O9S. Crystalinity of the compound was checked by X-ray powder diffraction studies, which reveal the crystalline nature of compound and data confirmed orthorhombic crystal system with Pmmm space group. Antibacterial screening for the compound suggested better antibacterial potency against K. pneumoniae and S. aureus bacteria. Conclusion: A novel compound has been isolated from Curcuma longa rhizome. Antibacterial assay suggested improved activity against selected pathogens relative to control drugs, Gentamicin.