Bortolomeazzi R, Berno P, Pizzale L, Conte L S
Food Science Department, Udine University, via Marangoni 97, 33100 Udine, Italy.
J Agric Food Chem. 2001 Jul;49(7):3278-83. doi: 10.1021/jf001271w.
The hydrocarbon fraction of 30 virgin olive oils was analyzed, focusing in particular on the sesquiterpenes. The oil samples were of different geographical origins and obtained from different olive varieties. The hydrocarbon fraction was isolated by silica gel column chromatography of the unsaponifiable fraction of the oils. The sesquiterpene hydrocarbons were then fractionated, on the basis of their degree of unsaturation, by AgNO3 TLC and silica gel AgNO3 column chromatography. The composition of the sesquiterpenes was more complex than previously reported. Among the 31 sesquiterpenes detected, 24 have been tentatively identified, by comparison of the linear retention indices on two capillary columns of different polarities and mass spectra with those reported in the literature. The total concentration of the sesquiterpenes in the oils analyzed ranged from about 2 to 37 ppm. Among the sesquiterpenes the more abundant were alpha-farnesene, alpha-copaene, eremophyllene, and alpha-muurolene. The alkenes present in the hydrocarbon fraction were isolated by TLC AgNO3 and characterized by GC-MS of their dimethyl disulfide derivatives. The series of n-Delta9-alkenes from C22 to C27, 8-heptadecene, and 6,10-dimethyl-1-undecene were detected. Among the n-alkanes, those with an odd number of carbon atoms predominated in all of the analyzed oils, the most common being C23, C25, C27, and C29. The concentration of the n-alkenes ranged from about 0.5 to 2 ppm, whereas for the n-alkanes the range was from 30 to 177 ppm.
对30种初榨橄榄油的烃类成分进行了分析，特别关注倍半萜类化合物。油样来自不同的地理区域，且取自不同的橄榄品种。通过对油的不皂化物进行硅胶柱色谱法分离出烃类成分。然后，根据倍半萜烃的不饱和度，通过硝酸银薄层层析和硅胶硝酸银柱色谱法对其进行分馏。倍半萜类化合物的组成比先前报道的更为复杂。在所检测到的31种倍半萜类化合物中，通过比较在两根不同极性的毛细管柱上的线性保留指数以及质谱与文献报道的结果，初步鉴定出了24种。所分析的油中倍半萜类化合物的总浓度范围约为2至37 ppm。在倍半萜类化合物中，含量较高的是α-法尼烯、α-可巴烯、异长叶烯和α-穆罗烯。通过硝酸银薄层层析分离出烃类成分中的烯烃，并通过其二甲二硫衍生物的气相色谱-质谱联用对其进行表征。检测到了从C22到C27的一系列n-Δ9-烯烃、8-十七碳烯和6,10-二甲基-1-十一碳烯。在正构烷烃中，所有分析的油中碳原子数为奇数的正构烷烃占主导，最常见的是C23、C25、C27和C29。正构烯烃的浓度范围约为0.5至2 ppm，而正构烷烃的浓度范围为30至177 ppm。
