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431.
H Chen F Chen Y-L Zhang J-Y Song 《Journal of industrial microbiology & biotechnology》1999,22(3):133-138
Hairy root cultures of Salvia miltiorrhiza were established by infecting sterile plantlets with Agrobacterium rhizogenes ATCC 15834, and the transformation was proved by direct detection of the inserted T-DNA by the polymerase chain reaction.
As determined by HPLC, these hairy root cultures had the ability to produce lithospermic acid B (LAB), rosmarinic acid (RA)
and other related phenolic compounds, the water-soluble active components of the plant. The effect of five different basal
media, MS, MS-NH<INF>4</INF> (MS without ammonium nitrate), B5, WPM and 6,7-V on the root growth and phenolic compound production
was studied. It was found that MS-NH<INF>4</INF> and 6,7-V media were superior to MS, B5 and WPM media in terms of both root
growth and phenolic compound production. The time course of biomass accumulation and phenolic compound formation was also
examined in the culture using MS-NH<INF>4</INF>medium. During cultivation, the content of RA in the roots was stable being
approximately 0.48% of dry weight while the content of LAB fluctuated between 0.73% and 1.61% of dry weight, and decreased
gradually at the stationary phase of growth. The highest production of LAB and RA was about 64 mg L−1 and 23 mg L−1, respectively.
Received 05 November 1998/ Accepted in revised form 06 February 1999 相似文献
432.
433.
Christian Westerkamp 《Plant Systematics and Evolution》1991,177(1-2):71-75
Contrary to most other bee species honeybees are highly eusocial and hold extremely long-lived societies. Their all-season activities force them to use whatever plants available and prevent any specific adaptations — in the flowers, in honeybees, and in all competing bees. This flexible behaviour in flowers has been a precondition for perennial colony life. But as bees evade becoming contaminated by pollen their visits often do not result in pollination. Honeybee monocultures thus must be avoided by all means. 相似文献