Taxol content in the seeds of Taxus SPP.

Abstract

The concentrations of taxol and related compounds in the mature dried seeds of several Taxus species were determined by HPLC. In addition, the taxol level of the seeds of T. cuspidata at different stages of maturation was studied. The variation in the taxane content was dependent on individual trees within species as well as among species. The average contents of taxol and its precursor, 10-deacetyl baccatin III (10-DAB III) in the mature seeds of different species were 67.3 ± 50 and 96.2 ± 83 μg g⁻¹ dry wt, respectively. In mature seed parts of T. cuspidata var. latifolia obtained from tree U5, the embryo weight was ca 0.2% of that of the dry weight of the whole seed and contained the highest level of taxol (894 μg g⁻¹) when compared with that obtained for the endosperm (23 μg g⁻¹) and testa (376 μg g⁻¹). However, the taxol content per seed was highest in the testa (20.5 μg) followed by the endosperm (0.75 μg) and embryo (0.18 μg). The taxol content of the fresh seed reached a maximum of 332 μg g⁻¹ and 20 μg seed⁻¹ at the middle stage of seed maturation and then decreased with further maturation. The taxol identification in the seed was confirmed by electrospray mass spectrometry.