Antibacterial Activity and Phytochemical Components of Leaf Extracts of Agave americana

Figures & data

Table 1 Percentage Yields of the 80% Methanol Extracts of Dried and Powdered Agave americana, Addis Ababa, June 2018

Plant Species	Part Extracted	Weight of Agave Americana Leaf Powder (g)	Weight of Crude Extract (g)	Percentage Yield w/w the 80% Methanol Crude Extracts (%)
Agave americana	leaf	100	15.11	15.11

Table 2 Antibacterial Effects of Agave americana Crude Extracts on Selected Strains of Bacteria, Addis Ababa, June 2018

Test Sample	Concentration mg mL	Zone of Inhibition on Bacterial Strains (mm)
Agave americana		SA (ATCC25925)	EC (ATCC25922)	PA (ATCC27853)	SAL (ATCC83859)
	100	34	23	28	28
	75	28	21	24	25
	50	25	20	21	23
	25	21	19	20	21
Gentamycin#	0.1	32	25	26	29

Note: ^#Positive controls.

Abbreviations: SA, S. aureus; EC, E. coli; PA, P. aeruginosa; SAL, S. typhi.

Table 3 Percentage Yields of Solvent Fractions of Agave americana, Addis Ababa, June 2018

Plant Species	Part Extracted	Petroleum Ether Fractional Extract		Chloroform Fractional Extract		Acetone Fractional Extract		Methanol Fractional Extract
Agave americana	leaf	Weight (gm)	% yield w/w	Weight (g)	% yield w/w	Weight (g)	% yield w/w	Weight (g)	% yield w/w
		0.0345	3.45	0.019	1.9	0.0546	5.46	0.243	2.43

Table 4 Antibacterial Effect of Solvent Fractions of Agave americana Against Selected Strains of Bacteria, Addis Ababa, June 2018

Test Sample	Solvent Fraction	Concentration mg mL	Zone of Inhibition on Bacterial Strains (mm)
Agave americana			SA (ATCC25925)	EC (ATCC25922)	PA	SAL (ATCC83859)
					(ATCC27853)
	Petroleum ether	75	40	27	22	23
		50	36	25	21	21
		25	32	21	20	19
	Chloroform	75	36	22	23	25
		50	30	21	22	23
		25	37	19	20	22
	Acetone	75	34	22	24	23
		50	32	19	22	22
		25	27	17	19	18
	Methanol	75	33	23	24	24
		50	29	22	20	22
		25	25	19	18	21
	crude	75	35	22	25	27
		50	28	21	22	23
		25	24	19	22	20

Abbreviations: SA, S. aureus; EC, E. coli; PA, P. aeruginosa; SAL, S. thyphi.

Table 5 Minimum Inhibitory Concentration (MIC) Values of Crude (80% Methanol) Extracts of Agave americana on the Tested Strains, Addis Ababa, June 2018

Plant Species	Concentration mg mL	Bacterial Strain
		SA (ATCC25925)	EC (ATCC25922)	PA (ATCC27853)	SAL (ATCC83859)
Agave americana	20	–	–	–	–
	10	–	–	–	–
	5	–	+	–	–
	2.5	–	+	–	–
	1.25	+	+	+	+
	0.625	+	+	+	+

Abbreviations: (+), presence of growth; (-), absence of growth; SA, S. aureus; EC, E. coli; PA, P. aeruginosa; SAL, S. typhi.

Table 6 Phytochemical Constituents of Crude Extract of Agave americana Leaves Using Chemical Test Methods, Addis Ababa, June 2018

Constituent	Presence in Crude Extract of Agave americana
Alkaloids	++
Saponins	+
Tannins	++
Anthraquinones	–
Phenolic compounds	++
Flavonoids	+

Notes: - = negative, ++ = strongly positive, + = positive.