不同树龄侧柏木精油差异的研究

Differences in the Essential Oils from Different Ages of Platycladus orientalis

本文采用超临界流体法提取三种不同树龄的侧柏木精油,并研究了三种侧柏精油在提取率、感官性状、精油组成和抑菌功效等方面的差异。研究结果表明,树龄越老的侧柏木的精油提取率越高,最高可达到9.98%,精油的芳香气味也更浓郁醇正;采用GC-MS法分析精油成分,发现树龄越老的侧柏木的精油其主要成分罗汉柏烯、雪松醇、花侧柏烯等含量也越高;采用最低抑菌浓度(MIC)法比较了三种精油的抑菌功能,发现树龄越老的侧柏木精油其MIC也越低,对四种细菌(金黄色葡萄球菌、乳酸菌、大肠杆菌和沙门氏菌)的MIC均可低至0.05 mg/m L,说明其具有高效的抑菌效果。本文研究结果表明,侧柏木的陈化时间对其精油的风味、含量、组成和功能等方面均具有重要影响,树龄越老的侧柏木精油利用价值越高。

Essential oils were extracted from three Platycladus orientalis woods of different ages by supercritical fluid extraction, and the differences in the extraction rate, sensory characteristics, composition, and antimicrobial efficacy of the three essential oils were studied. The results indicated that an older P. orientalis could yield a higher extraction rate of platycladus orientalis（up to 9.98%）, and the flavor of the essential oil was stronger and mellower. Gas chromatography-mass spectrometry was used to analyze the components of the essential oils, and the results showed that older P. orientalis had higher contents of the main active ingredients, including thujopsene, cedrol, and cuparene. The minimum inhibitory concentration（MIC） method was employed to compare the antimicrobial activities of the three essential oils. The result revealed that older P. orientalis had a lower MIC value, and the MIC values against four bacteria（Staphylococcus aureus, Lactobacillus, Escherichia coli, and Salmonella） all reached 0.05 mg/mL, showing a strong antimicrobial activity. This experimental result shows that the aging time of P. orientalis wood has an important influence on the favor, content, oil composition, and function of the essential oil, and the essential oil of older P. orientalis has a higher application value.