An In Vitro Synergistic Interaction of Combinations of Thymus glabrescens Essential Oil and Its Main Constituents with Chloramphenicol

Table 1

Composition of the essential oil of T. glabrescens.

Component	RT^a (min)	AIL^b	AIE^c	T. glabrescens (%)
Monoterpene hydrocarbons				11.07
α-Thujene	8.161	924.0	925.0	0.33
α-Pinene	8.400	932.0	932.1	0.29
Camphene	8.951	946.0	948.4	0.15
Sabinene	9.734	969.0	971.6	0.09
β-Pinene	9.897	974.0	976.5	0.10
Myrcene	10.320	988.0	989.0	0.59
α-Phellandrene	10.909	1002.0	1006.1	0.10
3-Carene	10.984	1008.0	1007.9	0.03
α-Terpinene	11.294	1014.0	1016.6	0.60
o-Cymene	11.620	1022.0	1025.6	4.73
Limonene	11.751	1024.0	1029.2	0.81
β-cis-Ocimene	11.980	1032.0	1035.6	0.15
β-trans-Ocimene	12.362	1044.0	1046.1	0.18
γ-Terpinene	12.822	1054.0	1058.7	2.75
Terpinolene	13.767	1086.0	1084.8	0.17
Oxygenated monoterpenes				57.14
Eucalyptol	11.861	1026.0	1032.3	0.56
trans-Linalool oxide	13.828	1084.0	1086.5	0.03
Linalool	14.437	1095.0	1103.2	5.49
α-Thujone	14.603	1101.0	1107.8	0.38
cis-p-Mentha-2,8-dienol	15.697	1133.0	1138.4	0.01
Borneol	16.956	1165.0	1173.0	0.47
4-Terpineol	17.249	1174.0	1181.1	0.47
α-Terpineol	17.790	1186.0	1196.1	0.79
trans-Dihydrocarvone	18.088	1200.0	1204.5	0.02
Nerol	18.842	1227.0	1226.3	1.18
Isobornyl formate	18.990	1235.0	1230.5	2.87
Neral	19.311	1235.0	1239.8	2.25
Geraniol	19.936	1249.0	1257.8	22.33
Geranial	20.396	1264.0	1271.0	0.50
Bornyl acetate	20.924	1287.0	1286.3	0.20
Nerol acetate	23.364	1359.0	1359.2	0.21
Geranyl acetate	24.244	1379.0	1385.8	19.38
Sesquiterpene hydrocarbons				14.56
α-Cubebene	23.065	1345.0	1350.2	5.51
α-Copaene	23.927	1374.0	1376.2	0.03
β-Elemene	24.409	1389.0	1390.7	0.09
β-Caryophyllene	25.384	1417.0	1421.3	1.04
α-trans-Bergamotene	25.770	1432.0	1433.6	0.05
Aromadendrene	25.952	1439.0	1439.4	0.12
(Z)-β-Farnesene	26.376	1440.0	1452.9	0.22
α-Humulene	26.487	1452.0	1456.4	0.13
γ-Muurolene	27.083	1478.0	1475.4	0.16
Germacrene D	27.302	1484.0	1482.4	1.57
β-Selinene	27.567	1489.0	1490.8	0.14
Bicyclogermacrene	27.734	1500.0	1496.2	1.01
β-Bisabolene	28.153	1505.0	1510.0	4.08
γ-Cadinene	28.258	1513.0	1513.6	0.11
δ-Cadinene	28.410	1522.0	1518.7	0.21
β-Sesquiphellandrene	28.563	1521.0	1523.9	0.09
Oxygenated sesquiterpenes				0.37
Spathulenol	30.140	1577.0	1577.0	0.29
Caryophyllene oxide	30.300	1582.0	1582.3	0.08
Phenolic compounds				14.00
Thymol	21.350	1289.0	1298.6	13.79
Carvacrol	21.499	1298.0	1303.0	0.19
Eugenol	23.155	1356.0	1352.9	0.02
Others				0.62
trans-2-Hexenal	5.987	846.0	850.2	0.03
1-Octen-3-ol	10.010	974.0	979.8	0.45
3-Octanol	10.596	988.0	997.2	0.14
Total				97.76

^aRT: retention time; ^bAIL: arithmetic (retention) index-literature data, and ^cAIE: arithmetic (retention) index experimentally determined on HP-5MS column.