The essential oils chemical compositions and antimicrobial, antioxidant activities and toxicity of three Hyptis species

Figures & data

Figure 1. GC chromatogram of H. suaveolens, H. rhomboidea and H. brevipes essential oils: (A) H. suaveolens; (B) H. rhomboidea; (C) H. brevipes.

Table 1. Analytical results of chemical constituents of H. suaveolens, H. rhomboidea and H. brevipes essential oils.

Name of		Percentage in samples (%)
components^a	RI^b	H. suaveolens	H. rhomboidea	H. brevipes
1R-α-Pinene	1020	1.04	–	–
1S-β-Pinene	1106	1.77	–	–
α-Phellandrene	1119	0.84	–	–
d-Limonene	1197	0.24	–	0.03
1,8-Cineole	1211	10.33	0.10	–
Leaf aldehyde	1215	0.31	0.17	–
η-Terpinene	1243	0.62	–	–
1-Octen-3-ol	1443	1.28	0.52	0.16
Thujopsene-I3	1448	–	0.54	–
α-Cubebene	1454	0.74	0.65	0.36
Ylangene	1480	–	0.31	–
Copaene	1490	3.25	1.83	0.49
Linalool	1539	0.15	0.76	0.24
(−)-Isocaryophyllene	1574	9.92	7.48	–
(−)-β-Elemene	1583	3.12	1.64	0.32
Caryophyllene	1599	16.17	–	9.72
Aristolene	1602	–	0.54	–
Benzene acetaldehyde	1636	–	0.61	0.11
Humulene	1642	–	0.29	0.09
cis,cis,cis-1,1,4, 8-Tetramethyl-4,7, 10-cycloundecatriene	1664	1.56	1.29	1.49
4,11-Selinadiene	1670	–	0.71	–
Cedrene	1681	0.29	0.05	–
Borneol	1701	–	6.03	0.26
Germacrene D	1702	0.65	0.57	0.59
α-Gurjunene	1704	0.34	1.58	–
(+)-β-Selinene	1710	1.28	–	–
γ-Muurolene	1712	–	0.48	–
Longifolene	1716	–	–	0.24
(−)-α-Selinene	1717	1.01	–	–
α-Muurolene	1718	–	2.11	–
(−)-β-Cadinene	1749	1.1	7.11	1.34
α-Sesquiphellandrene	1759	–	–	0.20
ç-Elemene	1795	–	0.17	1.44
l-Calamenene	1824	–	0.34	0.28
Thymol	1839	0.25	0.48	0.46
2-Hydroxycineole	1853	0.77	–	–
α-Isosafrole	1862	0.17	–	0.21
Phenylethyl alcohol	1903	0.67	–	–
Butylated hydroxytoluene	1914	–	29.90	–
Caryophyllene oxide	1983	8.36	0.58	2.58
Methyl eugenol	2004	1.79	7.79	11.46
Humulene epoxide II	2031	0.74	–	0.22
Cubenol	2049	0.83	–	0.15
9-Hexadecenoic acid	2058	1.30	–	–
Viridiflorol	2083	0.44	–	0.23
Cedrol	2129	0.57	–	–
Spathulenol	2130	0.70	–	0.10
tau-Cadinol	2163	0.45	–	–
3-Allylguaiacol	2167	4.07	–	62.67
Globulol	2201	0.34	0.07	–
cis-Asarone	2218	–	1.48	–
α-Cadinol	2225	0.32	–	–
β-Eudesmol	2245	–	0.38	–
Eudesm-7(11)-en-4-ol	2247	0.58	–	–
Sclarene	2325	2.29	–	–
Z-α-trans-Bergamotol	2356	0.35	–	–
(+)-Cembrene	2459	0.63	–	–
Abietatriene	2495	3.37	–	–
Phytol	2592	–	0.58	0.03
Palmitic acid	–	0.36	10.11	0.27
Linoleic acid	–	3.66	–	–
Total identified		89.03	87.25	95.74
Yield (% v/dry wt)		0.9	0.4	0.5

^aCompounds are listed in the order of their elution from a DB-WAX column.

^bRetention indexes calculated against C₈–C₂₆ n-alkanes on the DB-WAX column.

Table 2. Chemical compound classification of H. suaveolens, H. rhomboidea and H. brevipes essential oils.

	Percentage in samples (%)
Components class	H. suaveolens	H. rhomboidea	H. brevipes
Monoterpene hydrocarbons	4.51	0.00	0.03
Oxygenated monoterpenes	13.95	7.37	1.17
Sesquiterpene hydrocarbons	39.44	27.69	16.56
Oxygenated sesquiterpenes	13.68	32.03	3.28
Diterpenodis hydrocarbons	6.29	0.00	0.00
Oxygenated Diterpenodis	0.00	0.58	0.03
Aromatic compounds	5.86	7.79	74.13
Others (ketone, acid, etc.)	7.58	11.79	0.54
Total identified	89.03	87.25	95.74

Table 3. Antimicrobial activities of H. suaveolens, H. rhomboidea and H. brevipes essential oils (MIC μg mL⁻¹).

Sample	S.a	B.s	E.c	P.a	F.g	B.c	E.t	L.a
H. suaveolens	50	25	25	50	50	25	50	50
H. rhomboidea	12.5	12.5	6.25	6.25	25	12.5	25	25
H. brevipes	3.125	3.125	6.25	3.125	3.125	6.25	6.25	3.125

S.a, Staphylococcus aureus; B.s, Bacillus subtilis; E.c, Escherichia coli; P.a, Pseudomonas aeruginosa; F.g, Fusarium graminearum; B.c, Botrytis cinerea; E.t, Exerohilum turcicum; L.a, Lecannosticta acicola; Negative control, DMSO had no effect in the assay.

Figure 2. The structure of representative compounds of H. suaveolens, H. rhomboidea and H. brevipes essential oils.

Table 4. Brine shrimp lethality activity of H. suaveolens, H. rhomboidea and H. brevipes essential oils (LC₅₀ μg mL⁻¹).

Sample	H. suaveolens	H. rhomboidea	H. brevipes
LC50 (μg mL^−1)	62.2 ± 3.07	65.9 ± 6.55	60.8 ± 9.04

Negative controls, medium and DMSO had no effects in the assay; the values are expressed as means ± SD, n = 3, p < 0.05.

Figure 3. DPPH radical scavenging activity of H. suaveolens, H. rhomboidea and H. brevipes essential oils.