Anti-Herpes Simplex virus and antibacterial activities of Graptopetalum paraguayense E. Walther leaf extract: a pilot study

Figures & data

Figure 1. Procedure for evaluation of anti-HSV and antibacterial activities of GP extract in vitro.

Figure 2. Cytotoxic activity of GP extract on the viability of Vero and RD cell lines at 72 h treatment. Data are presented as percentage (%) of cell control.

Table 1. Cytotoxic activity of GP extract and ACV on Vero and RD cell lines, expressed as MNC and CC₅₀ obtained by different methods.

Tested agent	Method	Cell line	MNC (mg/mL)	CC50 (mg/mL)
GP extract	Cell morphology evaluation by microscopy	Vero	0.0001 ± 0.1	2.5 ± 0.13
		RD	0.0001 ± 0.05	2.5 ± 0.22
	Cell viability by MTT assay	Vero	0.0001 ± 0.12	2.5 ± 0.05
		RD	0.00001 ± 0.5	2.5 ± 0.08
ACV	Cell morphology evaluation by microscopy	Vero	0.05 ± 0.6	0.5 ± 0.02
		RD	0.05 ± 0.22	0.3 ± 0.32
	Cell viability by MTT assay	Vero	0.05 ± 0.1	0.4 ± 0.06
		RD	0.05 ± 0.32	0.4 ± 0.07

Table 2. Antiviral activity of leaf extract of G. paraguayense against wt HSV strains sensitive to ACV (Victoria, HSV-1) and (Bja, HSV-2).

Tested agent	Antiviral activity
	HSV-1 (strain Victoria)			HSV-2 (strain Bja)
	% of protection of the cells in MNC	EC50 (mg/mL) ± SD	SI	% of protection of the cells in MNC	EC50 (mg/mL) ± SD	SI
GP extract	97.5	0.0001 ± 0.08	25,000	25.5	0.01 ± 0.03	250
ACV	100	0.0005 ± 0.02	800	95.7	0.005 ± 0.12	80

Table 3. Antiviral activity of leaf extract of G. paraguayense against HSV-1/HSV-2 ACV^R mutants (DD, HSV-1) and (PU, HSV-2).

Tested agent	Antiviral activity
	HSV-1 (strain DD)			HSV-2 (strain PU)
	% of protection of the cells in MNC	EC50 (mg/mL) ± SD	SI	% of protection of the cells in MNC	EC50 (mg/mL) ± SD	SI
GP extract	65.5	0.001 ± 0.01	2 500	13	0.1 ± 0.02	25
ACV	10.8	0.02 ± 0.05	20	0	0.02 ± 0.03	20

Table 4. Antibacterial activity of total extract obtained from G. paraguayense.

Bacterial strain	MIC
	GP [mg/mL]	Referent antibiotic [mg/L]
S. aureus, ATCC 29213	2.5	Penicillin Gentamicin	0.250 0.250
E. faecalis, ATCC 29212	5.0	Penicillin Gentamicin	2 8
E. coli, ATCC 25922	>5.0	Gentamicin	2
P. aeruginosa, ATCC 27853	>5.0	Gentamicin	0.5
MRSA, NBIMCC 8327	2.5	Gentamicin	0.25
S. pyogenes, SAIM 10535	5.0	Penicillin	0.0625

MIC, minimal inhibitory concentration.

Figure 3. Biofilm formation of MRSA after exposure to leaf extract obtained from Graptopetalum paraguayense. Qualitative microscopic (40× microscopic magnification) and quantitative spectrophotometric (MBIC₅₀) evaluation. Scale bar = 50 μm; 40× magnification.