Extraction and Basic Testing for Antibacterial Activity of the Chemical Constituents in Suregada multiflorum

Abstract

                Extractions of biologically active chemical constituents from the leaves, bark and stem of Suregada multiflorum with a polarity sequence of hexane, dichloromethane and methanol were conducted. Antibacterial activities of the crude extracts were examined by paper disc agar diffusion and spread plate methods with Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Mycobacterium lacticola, Pseudomonas aeruginosa and Xanthomonas campestris. The crude extracts of the greatest inhibition activities, i.e. dichloromethane extracts, were chromatographed over a silica gel column using a single solvent and solvent mixtures of increasing polarity as the eluents. The bacterial growth inhibitions of the pure fractions were also examined to find out the most active fractions. 

                 The chemical constituents extracted from various parts of Suregada multiflorum provided high yields of polar fractions. The crude and pure fractions, particularly the polar compounds, of each part of the plant inhibited several tested bacteria. The purified fractions exhibited stronger inhibition than the crude extracts. The inhibition of Xanthomonas campestris growth indicated the potential of chemical constituents from Suregada multiflorum to inhibit plant bacterial diseases such as citrus canker and that they would probably be useful for canker prevention in replacing chemical pesticides.