Establishment of a cell suspension culture system of endangered Aquilaria sinensis (Lour.) Gilg

Aquilaria sinensis callus induced by stem tips were used to establish the suspension cell system. The results showed that the most suitable medium for callus induction and subculture is MS + 2.0 mg·L^-1 NAA + 1.0 mg·L^-1 6-BA. After 12 times of subculture, the energetic and loose callus, which were appropriate for cell suspension culture, were cultured and shook in liquid medium MS + 2.0 mg·L^-1 NAA + 1.0 mg·L^-1 6-BA + 500.0 mg·L^-1 casein hydrolysate (CH) to establish the suspension cell system. The growth curve of suspension cells showed a "S" type. At the beginning of the culture, cell density increased slowly; during 4 to 6 days, suspension cells reached logarithmic growth period; during 7 to 12 days, suspension cells were in the platform period; but after 12 days, cell density and activity went down obviously. Agarwood sesquiterpenes were not detected in the suspension cells during the growth period, however, they could be detected in MeJA treated suspension cells. In this study, a stable and active growing suspension cell system was established, which was a proper system to study the mechanism of agarwood sesquiterpene formation, and additionally provided a potential way to generate agarwood sesquiterpenes through application of cell culture.