Topik : Flora
Tahun : 2004
Prom the n-hexane extract of thallus of the Usnea articulata L. Hoffm. Collected from the Cibodas National Park Botanical Garden-Mount Gede Pangrango, West Java has been isolated know (+)-usnic acid possesed positive result with LC50= 0,653 ppm. Besides, the antibacterial activity of (+)- usnic acid against salmonella thyposa dan bacillus subtillis is known. Whereas from the acetone extract has been isolated the white crystal. From the structure elucidation by mean of spectral data (IR, UV/Vis, ¹H-NMR, ¹³C-NMR, 2D-NMR, and MS) can be know , that the compound has been constructed from 2 aromatic rings jointed with carboxyl hroup, 1 metoxy group, 2 hydroxy phenol, 1 carboxylic group dan 2 aromatic protons. It has molecule formulae = C19H20O7. the structure of the molecule closed to the structure of barbatic acid, but different in the location of the one aromatic proton and one hydroxy phenol. Therefore we suggested that the compound called isobarbatic acid, as the novel compound in the group of para-depside. The compound has antibacterial activity to salmonella thyposa dan Bacillus subtillis, but umfortunatelly no larvacidal activity againts 3 Aedes aegepty larvae until 55 ppm.