西藏不同种源光核桃仁脂肪酸组成分析

采用溶剂回流法及气相色谱法，分析全西藏范围内9 个种源的光核桃仁出油率、油脂种类及相对含量特征。结果表明，9 个种源的光核桃仁出油率差异显著，均值为44.96%；光核桃油中不饱和脂肪酸相对含量极高，均值为90.901%，主要由油酸和亚油酸组成，油酸相对含量的变化范围为45.280%～71.360%，最高值为芒康县的光核桃；亚油酸相对含量的变化范围为18.010%～44.340%，最高值为亚东县光核桃；饱和脂肪酸相对含量均值为9.099%，主要成分为棕榈酸和硬脂酸，棕榈酸相对含量的变化范围为5.829%～7.354%，最高值为亚东县光核桃；硬脂酸相对含量的变化范围为1.600%～3.034%，最高值为察隅县光核桃。基于11 种脂肪酸相对含量特征的聚类分析表明，米林县、左贡县、波密县、八宿县光核桃仁油脂相对含量特征相近，芒康县则与其他种源光核桃油脂特征差异较大。

Analysis of Fatty Acid Compositions in Prunus mira Kernels from Different Growing Areas in Tibet

Prunus mira kernels from nine Tibetan growing areas were analyzed for oil extraction yield and fatty acid composition using solvent reflux extraction and gas chromatography (GC). Results showed that the oil extraction yield from P. mira kernels varied significantly among different growing areas with an average of 44.96%. P. mira kernel oil was extremely rich in unsaturated fatty acids with an average of 90.901%, mainly oleic acid and linoleic acid. Oleic acid varied between 45.280% and 71.360% and was the most abundant fatty acid in the samples from Mangkang county, and linoleic acid ranged from 18.010% to 44.340%, showing the highest value in the samples from Yadong county. The mean content of saturated fatty acids was 9.099%, mainly palmitic acid and stearic acid, with palmitic acid ranging from 5.829% to 7.354% and showing the highest value in the samples from Yadong county, and stearic acid varying in the range of 1.600%–3.034% and being the most abundant saturated fatty acid in the samples from Chayu county. Clustering analysis based on the contents of 11 fatty acids indicated that P. mira kernel oils from Minling, Zuogong, Bomi, and Basu counties were similar while P. mira kernel oil from Mangkang county was quite different from those from other areas.