Phytochemical analysis of Withania somnifera leaf extracts by GC-MS and evaluating antioxidants and antibacterial activities

Figures & data

Table 1. Total phenolic content and flavonoid content of W. somnifera leaves extract.

Extraction Methods	Solvents	TPC (mg GAE/g)	TFC (mg QE/ g)
	Aqueous	140.59 ± 1.82^a, x	26.19 ± 0.62 ^h, w
Reflux	Methanol	198.24 ± 1.16^b, x	31.52 ± 0.91^i, w
	Acetone	123.83 ± 1.07^c, x	17.21 ± 1.22 ^j, w
	Ethyl acetate	109.48 ± 1.24^d, x	12.89 ± 1.29^k ^w
	Aqueous	101.41 ± 1.07^e, y	18.25 ± 1.48 ^l, z
Maceration	Methanol	187.74 ± 1.02 ^f, y	24.10 ± 0.97 ^m, z
	Acetone	110.69 ± 1.19^d, y	12.06 ± 1.68^k, z
	Ethyl acetate	144.06 ± 2.01 ^g, y	9.72 ± 1.32 ^n, z

A value in the same column for each solvent extracts followed by different letters (a-g &h-n) mean significant differences between extraction techniques and solvents estimated by Tukey’s multiple range tests (p $<$ 0.05).

Table 2. Radical scavenging activities of leaves extract in different solvents and extraction methods.

Extraction methods	Solvents	DPPH scavenging (%)	H2O2 Scavenging(%)
Reflux	Aqueous	69.01 ± 1.50^a, x	62.01 ± 2.17 ^h, w
	Methanol	75.23 ± 1.26^b, x	60.94 ± 2.01 ^h, w
	Acetone	54.63 ± 0.61^c, x	51.82 ± 1.33^i, w
	Ethyl acetate	42.57 ± 1.84^d, x	38.07 ± 1.02 ^j, w
Maceration	Aqueous	53.72 ± 1.04^c, y	57.19 ± 1.28^k, z
	Methanol	81.98 ± 0.49^e, y	68.01 ± 0.39 ^l, z
	Acetone	62.57 ± 1.14 ^f, y	76.18 ± 1.06 ^m, z
	Ethyl acetate	50.67 ± 0.90 ^g, y	46.09 ± 1.94 ^n, z

Different letter in the same column differs significantly (p < 0.05).

Table 3. Antibacterial activity of W. somnifera leaves in different solvent and extraction techniques.

Extraction Method	Zone of inhibition (mm) against bacterial species
	Solvent	Staphylococcus aureus (+ve)	Escherichia coli (-ve)
Reflux	Methanol	18.16 ± 0.18	39.75 ± 0.08
	Acetone	14.51 ± 0.91	30.09 ± 0.17
	Ethyl acetate	13.07 ± 0.38	22.49 ± 0.05
Maceration	Methanol	15.34 ± 0.02	35.02 ± 0.28
	Acetone	NA	14.19 ± 0.18
	Ethyl acetate	NA	NA

NA: Not activity. All measurements were made in triplicates (n = 3). Different letter in the same column differs significantly (p < 0.05).

Table 4. Identified compounds in W. somnifera methanol leaves extract.

Name	Formula	MW	RT	Area %
Tris(tertbutyl dimethylsilyloxy) arsane	C18H45AsO3Si3	468	5.421	1.64
Sydnone, 3-neopentyl-	C7H12N2O2	156	6.865	1.26
trans-2,4-Dimethylthiane, S, S- dioxide	C7H14O2S	162	8.231	4.09
Dicyclohexyl-, ethylphosphonate	C14H27O3P	204	8.454	1.24
2-Ethylthiolane, S, S-dioxide	C6H12O2S	148	8.909	2.26
Propanephosphonic acid, Bis (trimethylsilyl) ester	C9H25O3PSi2	240	10.664	2.76
Ethyl- 2-((dibutoxyphosphoryl) oxy)-3, 3, 3-trifluoropropanoate	C13H24F3O6P	364	11.198	1.27
Hexasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11 -dodecamethyl-	C12H38O5Si6	430	12.275	1.01
Arsenous acid, tris (trimethylsilyl) ester	C9H27AsO3Si3	342	17.608	2.43
Heptasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11, 1 3, 13-tetradecamethyl-	C14H44O6Si7	504	33.573	50.04

*RT- Retention Time (min), MW- molecular weight (g/mol)

Data availability statement

The data used to support the findings of this study are included within the article.