3. Results
3.1. Purification and Identification of Andrographolide. The
phytoconstituents eluted under different peaks were assayed
individually in vitro on Plasmodium falciparum. The particular
phytoconstituent eluted under peak “e” (retention
time 3.78) showed potent anti-malarial activity compared
to the compounds eluted under peaks a, b, c, and d
(Figure 1(a)). The compound of peak “e” was later identified
as andrographolide by comparing the retention time of
pure andrographolide (Sigma, Cat no. 365645) which was
run as positive control (Figure 1(b)) and finally by using
standard methods of compound identification [15, 17, 18].
Approximately, 50 cycles of HPLC purification were carried
out to obtain a sufficient amount of test compound, andrographolide
(Figure 1(c)) for their in vitro anti-plasmodial
assays.