Distribution, occurrence, and cluster analysis of new polyprenyl acetones and other polyisoprenoids from North Sumatran mangroves

Background. Mangrove forests have long been known as a source of phytochemical compounds producing various secondary metabolites. Despite the ubiquitous diversity of polyisoprenoids in the plant kingdom, few studies have focused on the distribution of polyisoprenoids in mangrove plants. The present study describes the distribution and occurrence of a new class of prenyl derivates-polyprenyl acetone as well as other polyisoprenoids in fourteen species of Indonesian mangroves, with an emphasis on chemotaxonomic importance. Material and methods. The leaves and roots of fourteen North Sumatran mangroves were analyzed using two-dimensional thin layer chromatography and electrospray ionization mass spectrometry. Results. In the leaves, the distribution of several types of polyprenyl acetones, polyprenols, and dolichols was detected and classified into types: type-I, having a predominance of dolichols over polyprenols (more than nine-fold), was observed in Acrostichum aureum (younger leaves), Avicennia alba, Av. lanata, Av. officinalis, Bruguiera parviflora, Ceriops tagal, Nypa fruticans, and Rhizophora mucronata; type-II, having the presence of both polyprenols and dolichols, was observed in Acanthus ilicifolius, Acr. aureum, B. cylindrica, and R. apiculata; type-III having a predominance of polyprenols over dolichols (more than nine-fold), was not observed in any North Sumatran mangroves; type-IV, having the presence of both polyprenyl acetones and dolichols, was observed in Aegiceras corniculatum; type-V, having the presence of polyprenyl acetones, polyprenols, and dolichols, was observed in Sonneratia caseolaris and Xylocarpus granatum. In the roots, type-I distribution was observed in Ae. corniculatum, Av. alba, Av. lanata, Av. officinalis, B. parviflora, C. tagal, N. fruticans, R. apiculata, R. mucronata, S. caseolaris, and X. granatum. Type-II distribution was observed in Ac. ilicifolius, Acr. aureum, and B. cylindrica. Type-III, -IV, and -V distributions were not observed in mangrove roots. Cluster analysis demonstrated that polyisoprenoid patterns in the leaves and roots form distinct separation into appropriate genera and tribe, suggesting that mangrove polyisoprenoids are chemotaxonomically significant. Conclusions. The major polyisoprenoid alcohols in Indonesian mangroves were found to be dolichols rather than polyprenols. The diversity of polyisoprenoids in both leaves and roots of mangroves may provide chemotaxonomic marker. The discovery of a new class of polyprenyl acetone is the first report from mangrove plants.