| Taxol (paclitaxel), isolated from the bark and shoots of Taxus spp., is a very important antitumor agent in treatment for ovarian cancer and breast cancer. The limited resource of Taxus spp. makes it be a relatively expansive drug and affects its long and widely clinical use. Attempts have been made in finding new means to solve the problem of taxol source. Taxus tissue and cell culture has been viewed as a potential one.In this experiment, 14 callus strains were established from different plants of T. yunnanensis, T. cuspidata, T. chinensis, T. chinensis var. mairei and T. media; the effects of 2,4-dichlorophenoxyacetic acid (2,4-D) concentrations, sampling times and illumination on callus formation from stem segments of T. yunnanensis and T. cuspidata were investigated; taxol contents in different callus strains were compared and a callus strain (TY6) with relatively high growth rate and taxol content was obtained; and the growth kinetics and taxol accumulation and some factors the growth and taxol production in callus and cell cultures were studied. The following results were obtained:1. In darkness, 50%70% of stem segments of the above five Taxus species formed callus when cultured on induction medium with mineral composition of B5 medium, 100.0 mg·L-1 inositol, 1.25 mg·L-1 nicotinic acid, 1.0 mg·L-1 vitamin B1, 0.5 mg·L-1 vitamin B6, 0.1 mg·L-1 N6-benzylaminopurine (BAP), 13 mg·L-1 2,4-D, 1.0 g·L-1 lactablumin hydrolysate, 20.0 g·L-1 sucrose and 8.0 g·L-1 agar. The optimum 2,4-D concentration was 2.0 mg·L-1 for callus induction from the stem segments of T. yunanensis and T. chinensis var. mairei. Stem explants of T. yunanensis had high callus formation frequency (over 70%) whether induced in... |
