In vitro antiplasmodial and antimicrobial potential of Tagetes erecta roots

Figures & data

Figure 1.  Structure of compound 1.

Table 1.  Percentage (%) inhibition of schizonts by various successive extracts of the roots of Tagetes erecta and the new bithienyl compound 1 on chloroquine sensitive (MRC-pf-2) and chloroquine resistant (MRC-pf-56) strains of Plasmodium falciparum.

Plant extract/isolate	Inhibition (%) of schizont maturation (mg/mL)*						IC50
	0.5	0.25	0.12	0.06	0.03	0.01
P. falciparum MRC-pf-2
Petroleum ether	58.62	51.2	43.11	34.50	26.92	16.32	0.22 ± 0.05 mg/mL
Chloroform	76.02	66.5	58.62	51.91	42.23	26.51	0.05 ± 0.01 mg/mL
Ethyl acetate	81.5	71.36	65.01	60.52	53.02	45.15	0.02 ± 0.01 mg/mL
Methanol	70.56	64.23	52.01	43.06	32.22	21.08	0.09 ± 0.02 mg/mL
Aqueous	53.38	47.16	41.01	35.5	28.01	18.16	0.31 ± 0.05 mg/mL
Compound 1	100.0	95.50	82.26	68.06	59.45	51.25	0.01 ± 0.01mg/mL
Chloroquine	100.0	100.0	100.0	100.0	100.0	100.0	0.51 ± 0.05 µg/mL
P. falciparum MRC-pf-56
Petroleum ether	56.23	45.05	34.11	27.21	20.05	15.25	0.37 ± 0.05 mg/ml
Chloroform	64.15	58.02	51.5	41.55	31.58	22.16	0.09 ± 0.02 mg/mL
Ethyl acetate	80.05	66.15	55.05	46.12	35.38	24.6	0.07 ± 0.02 mg/mL
Methanol	61.88	54.26	44.19	38.59	27.12	18.15	0.15 ± 0.03 mg/mL
Aqueous	50.16	41.02	32.18	28.11	21.03	15.21	0.49 ± 0.05 mg/mL
Compound 1	83.59	74.26	65.53	59.81	53.12	45.01	0.02 ± 0.01 mg/mL
Chloroquine	100.0	100.0	100.0	100.0	100.0	100.0	1.3 ± 0.01 µg/mL

*IC₅₀ values are mean ± standard error mean (n = 3).

Table 2.  Antimicrobial activity of successive extracts of Tagetes erecta roots.

Test organisms	Inhibition zone diameter (mm)^#
	Petroleum ether	Chloroform	Ethyl acetate	Methanol	Aqueous	Comp-1	Cephalexin	Clotrimazole	1% DMSO
S. aureus	21.6 ± 0.28	24.6 ± 0.28	19.3 ± 0.28	18.3 ± 0.28	15.6 ± 0.28	31.1 ± 0.28	48.02 ± 0.63	NT	-
B. subtilis	24.6 ± 0.28	22.3 ± 0.28	23.6 ± 0.28	22.3 ± 0.05	20.3 ± 0.28	34.6 ± 0.15	47.03 ± 0.28	NT	-
E. coli	18.3 ± 0.28	17.3 ± 0.28	20.3 ± 0.28	18.1 ± 0.86	13.6 ± 0.28	31.5 ± 0.05	48.6 ± 0.28	NT	-
M. luteus	18.3 ± 0.28	21.6 ± 0.86	21.3 ± 0.28	21.3 ± 0.63	15.6 ± 1.21	28.6 ± 0.05	47.3 ± 1.21	NT	-
P. aeruginosa	19.3 ± 0.63	20.6 ± 1.21	18.6 ± 0.28	21.6 ± 0.28	16.6 ± 0.28	25.1 ± 0.15	49.6 ± 0.63	NT	-
C. albicans	20.3 ± 0.86	21.6 ± 0.28	16.2 ± 0.05	17.6 ± 0.63	14.5 ± 0.63	29.1 ± 0.15	NT	47.2 ± 0.28	-
A. niger	25.3 ± 0.86	17.3 ± 0.86	16.3 ± 0.86	21.3 ± 0.05	13.3 ± 0.86	26.1 ± 0.11	NT	42.3 ± 0.63	-

^#Values are mean ± standard error mean (n = 3). Significantly different from standard at *p <0.001. NT, not tested; ‘–‘, no inhibition.

Table 3.  Minimum inhibitory concentration (MIC) of the successive extracts of Tagetes erecta roots and the newly reported compound 1.

Testorganisms	MIC (µg/mL)*
	Petroleum ether	Chloroform	Ethyl acetate	Methanol	Aqueous	Compound 1	Cephalexin	Clotrimazole	1% DMSO
S. aureus	25	12.5	25	25	50	3.12	0.31	NT	-
B. subtilis	12.5	25	12.5	25	25	3.12	0.31	NT	-
E. coli	25	25	25	25	50	3.12	0.31	NT	-
M. luteus	25	25	25	25	50	6.25	0.31	NT	-
P. aeruginosa	25	25	25	25	50	6.25	0.31	NT	-
C. albicans	25	12.5	50	50	50	3.12	NT	0.62	-
A. niger	12.5	50	50	25	100	6.25	NT	0.62	-

*Experiment was performed in triplicate (n = 3) and the values expressed as mean. NT, not tested; ‘–‘, no inhibition.