scaffolds and their possible targets.  

2. LIFE CYCLE OF THE MALARIA PARASITE:  

LIVER AND BLOOD STAGES  

In (Fig 1), a pictorial view of the asexual stages: sporo￾zoites, liver (exoerythrocytic stages) and blood stage (eryth￾rocytic stage) of the P. falciparum life cycle inside the hu￾man host, is illustrated. During feeding, the infected female  

Anopheles mosquito exposes the sporozoites to the human  

blood circulation. The sporozoites move to the liver via

blood and stay in the hepatocytes (the liver cells) for 7-10  

days [14]. Within the hepatocytes, the sporozoites multiply  

into schizont and produce approximately 100,000 of mero￾zoites resulting in the final rupturing and releasing of daugh￾ter parasites (merozoites). These merozoites enter into the  

human bloodstream invading erythrocytes and hence giving  

rise to ring stage. In the ring stage, the merozoites invade  

more and more red blood cells and further replicate into en￾larged ring shape trophozoites in the RBCs [15]. Trophozoi￾tes exhibit high metabolic activity, having rapid hemoglobin  

catabolism. After several asexual cycles, some of the mero￾zoites do not proceed to become trophozoites but instead  

develop a sexual form known as gametocytes. These game￾tocytes are consumed by a mosquito through another blood  

meal [35]. This process repeats itself completing the life cy￾cle of P. falciparum. Each stage of the P. falciparum life  

cycle opens the scope for a drug target. This article covers  

the efficacy of the antimalarial drugs potent against both BS  

and LS of Plasmodium parasites.  

Fig. (1). Schematic representation of the liver and blood stages of  

the P. falciparum life cycle inside the human body.  

3. COMPOUNDS WITH POTENTIAL TO INHIBIT  

LIVER AND BLOOD STAGE MALARIAL INFEC￾TION  

3.1. Compounds Isolated from Medicinal Plants

Natural products like quinine and artemisinin have been  

significantly used as antimalarial agents [36]. Likewise,  

Maria-José U. Ferreira and her group worked on the isolation  

of Momordica balsamina L. (Cucurbitaceae), identified as  

the African pumpkin or the balsam apple. It is widely used in  

the subtropical and tropical regions of the world [37]. They  

have isolated sixteen triterpenoids from this medicinal plant  

study their efficacy against LS of P. berghei [38]. They have  

also determined the luminescence intensity in Huh7 cells  

infected with a firefly luciferase expressing P. berghei line,  

PbGFP-Luccon, and against the blood stages of chloro￾quine-resistant clone Dd2 and chloroquine-sensitive strain  

3D7 of P. falciparum [39]. Thus, illustrating their role as  

dual stage inhibitors. On the same cell line, the toxicity of  

these compounds was checked by the fluorescence meas￾urement of the cell confluency. Karavoate B (1), a derivative  

having two acetyl residues displayed the highest antimalarial  

activity at the minimum concentration i.e. 1 µM, without any  

toxicity towards the Huh7 cells. The reduction in the P. ber￾ghei infection was based on the dose-dependent rate. Kara￾voate B (1), is also a powerful inhibitor of BS of P. falcipa￾rum, therefore displays a dual-stage antimalarial activity.  

In erythocytic stages of P. falciparum, triacetylbalsami￾nol F (2) exhibited the highest antiplasmodial activity (IC50:  

0.2 µM, Dd2; 0.4 µM, 3D7). In addition, minimal cytotoxic￾ity (IC50> 133.3 µM) was displayed by derivative 2. Apart  

from this, a greater SI value was found for 2 (SI >342.9 and  

162.4 for PfDd2 and Pf3D7 strains, respectively). Compound  

2 was also displayed the superior antiplasmodial activity