Flavonoids and anthocyanins from six Cassytha taxa (Lauraceae) as taxonomic markers

Abstract

1. Subject and sourceThegenusCassytha(Lauraceae)isaparasiticherb,whichcontainsca.20speciesandisdistributedinPacificRimcountries,mainly Australia, Africa, America and Japan (Mabberley, 1997). The leaves are degenerated and almost assimilate into thestem, which has small elliptical haustoria (Weber, 1981). Three Cassytha taxa, Cassytha filiformis L. var. filiformis, C. filiformisvar. duripraticola Hatus. and Cassytha pergracilis Hatus., are distributed in Japan, and the latter two are listed as endangeredplants by the Ministry of Environment, Japan. However, their taxonomic treatment underwent various changes (Hatusima,1971, 1975, 1978; Hatusima and Amano, 1994). Based on the specimens in Australia, Hatusima and Amano (1994) andHatusima (1978) treated C. filiformis var. duripraticola as Cassytha pubescens R. Br., and C. pergracilis as Cassytha glabella R.Br. However, it was difficult to classify them with only morphological characters. In this study, we describe the flavonoidsfrom the aerial parts of six Cassytha taxa and chemotaxonomically discuss them. The Cassytha species examined in this studywere collected in the sites described in Table 1. Voucher specimens were deposited in the Herbarium of National Museum ofNature and Science, Japan (TNS).2. Previous workPhylogeneticanalysesof thefamilyLauraceaeincludingCassytha,CassythaciliolataNees,C.filiformisandC.pubescenshavebeen carried out (Rohwer, 2000; Chanderbali et al., 2001). As chemical components in Cassytha species, many aporphine