Chemical structures of the condensed tannins in the fruits of Diospyros species

The structural variety of the condensed tannins (proanthocyanidins) in the fruits of 16Diospyros species are reported. Eleven species contained condensed tannins mostly consisting of a mixture of catechin (CA) and gallocatechin (GCA) repeating units; the other five species did not. The GCA content in the CA-GCA total varied from 0.3% to 84.6%. The number of esterified gallic acid per one flavan repeating unit (degree of galloylation, DG) ranged from 0.01 to 0.89. The GCA content was found to be proportional to the DG values. Thus, 16Diospyros species tested may be classified into five groups by the analytical data of their condensed tannins. It may be interesting to compare their structural characteristics with those of the condensed tannins in other fruits, leaves, woods, and barks from the viewpoint of their biosynthesis and function in the plants.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1995     

Analysis of phylogenetic relationships in Mangifera by restriction site analysis of an amplified region of cpDNA

The phylogenetic relationship of 13 Mangifera species collected in Thailand were examined. Among these species, M. foetida, M. odorata, and M. sylvatica have been cultivated as fruit crops for local markets in Thailand, as well as M. indica (common mango). The other nine wild species also seem to have potential values as rootstocks and breeding materials for tolerance to critical environmental conditions. By restriction fragment length polymorphism (RFLP) analysis of a particular region of cpDNA, these species were classified into two groups. The first group consisted of M. indica and M. sylvatica, and the second group consisted of M. caloneura, M. cochinchinensis, M. collina, M. flava, M. foetida, M. gedebe, M. griffithii, M. macrocarpa, M. oblongifolia, M. odorata, and M. pentandra. The species belonging to the same group are monomorphic for 20 restriction enzymes tested. The present study indicated low diversity in the amplified region of cpDNA among Mangifera species tested, even though the species in the second group were scattered to different subgenera and sections.