The Madagascar periwinkle (Catharanthus roseus) produces numerous
indole alkaloids, several of which have an important pharmaceutical uses such
as ajmalicine. The relationship between hypoxia and ajmalicine production in a
cell medium culture of C
atharanthus roseus were investigated during the cycle
of cell culture, as well as the growth in fresh and dry matter. The results show
that the lack of oxygenation in C20D cells provokes a very strong inhibition in
accumulation of the alkaloids and of other possible substances. This can be
explained by the absence of some downstream enzymes involved in the
biosynthesis chain of alkaloids or by the blockage of the upstream terpenes to
the production stage. Reoxygenation did not restore hypoxia effect on the
alkaloid accumulation.
Moreover, the present study showed that the addition of the loganin in the
4th day, in the cell culture medium subjected to hypoxia restored the alkaloid
production.
Also, the results show that the BAP increases the ajmalicine production. The
effect of hypoxia was not shown in the presence of cytokinine. The BAP can
without doubt decrease the effects of the hypoxia and increases the ajmalicine
production.
This investigation was carried out at Tissue Culture Laboratory, Department
of Horticulture, University of Mosul, Iraq during 2012-2014) on Catharanthus
roseus Variety; Nirvana Pink Blush, which is one of the important medicinal
plant, containing
a group of alkaloids. Parts of leaves, nodes, and internodes were
cultured on MS medium supplemented with NAA for callus initiation, data were
taken after 28-day results refer that highest weight of callus; 0.612g, 0.639g ,0.835g
were obtained from cultivated parts of leaves, nodes and internodes on MS medium
supplemented with 1.0mg/l NAA respectively. Callus was initiated and cultured
using parts of leaves, nodes and internodes on MS medium supplemented with BA
and 1.0 mg/l of NAA, after 50 days.