Optimal inductive and cultural conditions of Polygonum multiflorum transgenic hairy roots mediated with Agrobacterium rhizogenes R1601 and an analysis of their anthraquinone constituents.
BACKGROUND
Polygonum multiflorum is an important medicinal plant. Hairy roots systems obtained by transforming plant tissues with the natural genetic engineer Agrobacterium rhizogenes can produce valuable biological active substances, which have immense potential in the pharmaceutical industry.


OBJECTIVE
To optimize the inductive and cultural conditions of P. multiflorum hairy roots and to identify the major active secondary metabolites in hairy roots.


METHODS
P. multiflorum hairy root were mediated with A. rhizogenes R1601 to induce hairy roots. Four combinations, including Murashige-Skoog (MS), 1/2 MS, B5, and White, were investigated to optimize the culture medium. MS medium was selected for the growth measurement. The qualitative and quantitative determinations of free anthraquinone in hairy roots were compared with the calli and aseptic plantlets using high-performance liquid chromatography.


RESULTS
The inductive rates of hairy roots by leaves were higher than for any other explants. The presence of agropine in the P. multiflorum hairy roots confirmed that they were indeed transgenic. MS medium was the most suitable of the four media for hairy root growth. Meanwhile, the growth kinetics and nutrient consumption results showed that the hairy roots displayed a sigmoidal growth curve and that their optimal inoculation time was 18-21 days. The determination of the anthraquinone constituents indicated that the rhein content of the hairy roots reached 2.495 μg g(-1) and was 2.55-fold higher than that of natural plants.


CONCLUSIONS
Transgenic hairy roots of P. multiflorum could be one of the most potent materials for industrial-scale production of bioactive anthraquinone constituents.
Department of Natural Medicinal Chemistry, College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, China.
Bing
B
Huang
Department of Natural Medicinal Chemistry, College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, China.
Huanjie
H
Lin
Department of Natural Medicinal Chemistry, College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, China.
Chuanyan
C
Yan
Department of Natural Medicinal Chemistry, College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, China.
Hongyan
H
Qiu
Biotechnology Institute of Chinese Materia Medica, Jinan University, Guangzhou, China.
Lipeng
L
Qiu
Biotechnology Institute of Chinese Materia Medica, Jinan University, Guangzhou, China.
Rongmin
R
Yu
Agrobacterium rhizogenes R1601; Polygonum multiflorum; anthraquinones; transgenic hairy roots