Chemical Constituents Of Mitrella Kentii ( Annonaceae ) Ainnul Hamidah
Abstract: Mitrella kentii which belongs to the Annonaceae family is a tree-climbing liana found in the Malaysian Peninsula, Islands of Sumatra, Borneo, and New Guinea. This species was studied in 1972 for their alkaloids, 1997 and 2012 for their non-alkaloid constituents. In this study, chalcones, Desmosdumotin C (1) and their tautomer, 2-cinnamoyl3-hydroxy-5-methoxy-4,6,6-trimethylcyclohexa-2,4-dienone (2), flavanone, 7-hydroxy-5,6-dimethoxy-2-phenylchroman4-one (3), oxoaporphine alkaloids, Liriodenine (4) and Atherospermidine (5) and also terpenoid, -Sitostenone (6) have been isolated from this species. All these compounds were isolated for the first time from Mitrella kentii except Liriodenine (4). The isolated compounds were elucidated using spectroscopic techniques such as UV, IR,1D and 2D NMR and mass spectroscopy and by comparison their spectral data with those previously reported in the literatures. Desmosdumotin C (1) showed the anti-ulcer activity.
The alkaloids of Mitrella kentii (Annonaceae)
Mitrella kentii (Bl.) Rliq. of the family Annonaceae is a tree-climbing liana, found in the oak-forests of New Guinea. The alkaloidal constituents of this species have not previously been examined though field tests1 indicated their presence in the bark. Thin-layer chromatograms of the crude alkaloid mixture (yield: 0.063% of dry weight) resembled those originating from Scheffe~oomita subaequalis,2 another New Guinean liana of the same plant family. In fact all four alkaloids isolated were also present in S, subaequalis. The three main constituents were identified as liriodenine, anonaine, and asimilobine by direct comparison with authentic specimens. The fourth, minor, alkaloid was shown to be identical with aequaline.
THE IRON-ACETOCARMINE METHOD OF FIXING AND STAINING CHROMOSOMES
A short description of this procedure was given in Vol. 55 of the American Naturalist, pp. 573â€”574. The method has now been used almost daily for five years, and certain improvements have suggested themselves. The solution can be prepared by mixing about equal volumes of glacial acetic acid and water. To this is added powdered carmine in excess. The liquid is then â€ ? just brought to boil, cooled, and decanted. To the red solution there are then added a few drops of a solution of ferric hydrate in 50 per cent. acetic acid, to act as a mordant. The amount of iron varies with different objects. Too much produces a precipitate in a short time. The more