Table 1.

A summarized synergistic combination of plant natural products in the treatment of malaria

Positive interaction	Combination	Mechanism of action	FIC	Reference
Chloroquine resistant malaria	Cinchona alkaloids (quinine with quinidine and cinchonine)	Not defined	Lower than 1	[118]
	Artemetin and flavones casticin	Casticin enhances the in vitro activity of artemisinin by 3–fivefold by high antioxidant/radical scavenging activities	Not defined	[119]
	Picroliv (Picrorhiza kurroa)-chloroquine	Picroliv enhancing chloroquine efficacy against experimental murine malaria by induction of strong immuno-potentiating response	Not defined	[120]
	Andrographis paniculata and Hedyotis corymbosa extracts – Curcumin	The extracted plant material inhibits the ring stage of the parasite and increases the Curcumin efficacy	Lower than 1	[121]
	Chloroquine-Vernonia amygdalina leaf extract	Restore the prophylactic and therapeutic efficacy of chloroquine against Plasmodium berghei malaria in mice	Not defined	[122]
	Chloroquine- Bidens pilosa leaves	B. pilosa extract reverses resistance to chloroquine	Not defined	[123]
	Crude alkaloids of Strychnos myrtoides Gilg & Busse-chloroquine	The extract enhances chloroquine effectiveness against a chloroquine-resistant strain of Plasmodium falciparum	Not defined	[124]
	Icajine, isoretuline, and strychnobrasiline (Strychnos plants) – mefloquine and icajine—chloroquine	Reverse chloroquine resistance in in vitro tests with P. falciparum	Not defined	[125]
	EGCG (green tea)-artemisinin	EGCG potentiates the antimalarial effects of artemisinin without interfering with the folate pathway	Not defined	[126]
Complementary mechanisms of action	Curcumin–Artemisinin	Curcumin inhibits both CYP2B6 and CYP3A4 involved in the human liver metabolism of artemisinin	Lower than 1	[127]
	Artesunate- Telfairia occidentalis	T. occidentalis enhanced hematological parameters and rapid rate of recovery in P. berghei-infected mice	Not defined	[128]
	Curcumin- piperine (Piper nigrum seeds)	Piperine boosts the bioavailability of curcumin by 2000% in humans by inhibition of glucuronidation and reduction of the gastrointestinal transit and also increased its serum concentration, and absorption	Not defined	[129]
	(-)-Epigallocatechin-3-gallate (EGCG) (green tee) and piperine(black pepper)	Piperine enhanced the bioavailability EGCG by inhibiting glucuronidation and gastrointestinal transit	Not defined	[130]
	Curcumin (Curcuma longa L–arteether	Curcumin increases the efficacy of arteether against P. berghei-infected mice by activation of TLR2-mediated innate immune response which induce production of anti-parasite antibodies	lower than 1	[131]
Decrease adverse effects	Glycyrrhiza glabra, Ziziphus jujube and Zingiber officinale Febrifugine	The extracted plant material may be attenuated any hepatotoxicity from febrifugine	Not defined	[132]