In 2002, phytochemical screening and analytical chromatography were used to study the presence of phenolic compounds and leucoanthocyanins in "N. × sarawakiensis" and its putative parent species. The research was based on leaf material from dry herbarium specimens. Eight spots containing phenolic acids, flavonols, flavones, leucoanthocyanins and 'unknown flavonoids' 1 and 3 were identified from chromatographic profiles. The distributions of these in "N. × sarawakiensis", "N. muluensis" and "N. tentaculata" are shown in the adjacent table. A specimen of "N. × sarawakiensis" grown from tissue culture ("in vitro") was also tested.