Study on Characteristic Separation, Identification and Antimicrobial Activity of Main Compounds from the Rhizomes of Alpinia Allughas.

Abstract

Alpinia allughas Rosc. is a Zingiberace herb has been used in this study. A systematic study has been done for the chemical constituents of this plant and bioactive compounds responsible for the medicinal properties were identified by the chemical examination of rhizome extract. Also the antimicrobial properties of the active compounds has also been studied. To carryout the studies the extract of crushed dried rhizomes of A. allughas was partitioned with chloroform solvent (Hexane, CHCl₃, EtOAc, BuOH) system. Fractions are subjected to column chromatography on silica gel or alumina. Column was packed in pure petroleum ether and ran with increasing percentage of ethyl acetate as eluent. The compounds were fractionated and isolated from petroleum ether and ethyl acetate  with different  polarities  1%, 2% 3% 4%, 5%, 8%,10% increasing order with help of  column chromatography and thin layer chromatographic technique. The chloroform extract of rhizomes of Alpinia allughas showed the presence of five prominent and a number of other spots on thin layer chromatography (TLC). All the fractions were collected and distilled over water bath. TLC of each fraction was regularly checked in various combinations of petroleum ether-ethyl acetate and chloroform-methanol. Compounds A, B, and C were isolated at different combinations of petroleum ether and ethyl acetate on silica gel for that the column extract was subjected to column chromatography over silica gel. Elemental analysis were carried out for each extracted compounds followed by various spectral analysis including Infra red, ¹H NMR, ¹³C NMR and mass spectroscopy. Finally the antimicrobial properties of all the active compounds extracted was studied against the three different bacterial strains.