Study On Bioactive Compounds In Three Camellia Seed Oils And Their “Fancy Tiles” Development

Oils from seeds of Camellia genus plants, which belong to the family Thecae, are all called “tea seed oil” in oil industry and research, including C.sinensis seed oil,C.oleifera seed oil and C.camellia seed oil. Similar source and lack awareness of the three oils make misunderstanding and confusion in their development.With the three oils mentioned above, the following work was conducted based on the investigations of the germ plasm resources of Camellia and the main producing areas of Camellia seed oils:(1) Analysis and comparison of traits and chemical composition in Camellia seeds.(2) Analysis and determination of fatty acids of Camellia seed oils using GC.(3) A qualitative and quantitative method with GC-MS was developed for determination of phytosterols in Camellia seed oils.(4) A qualitative analytical method with HPLC-Q-TOF-MS was developed for identification of phenolic compounds and a quantitative analytical method with HPLC-QQQ-MS was developed for determination and analysis of 24 phenolic compounds in different Camellia seed oils.(5) Different chemometric methods were applied to analyze the characteristics of Camellia seed oils, and “Fancy Tiles” of three oils were established. The results and conclusions are as follows:(1) The traits and chemical composition of three groups of Camellia seeds were excellent for oil development, the kernel content ranging between 56.16% and73.45%, crude fat content ranging between 26.33% and 54.00%. Based on the grey correlation analysis, the correlation index in the sequence was: oil content > kernel content > ash > hundred grain weight > moisture and volatile matter > crude protein >crude starch.(2) There were 22, 21, and 21 fatty acids in C.sinensis, C.oleifera, and C.camellia seed oils, respectively. Oleic, linoleic, palmitic and stearic acids were the major FAs,whose percentage ranged between 97.85% and 98.52%. It was very similar between C.oleifera and C.camellia seed oils on the MUFA(79.04%~81.17% and77.26%~81.19%, respectively) and PUFA(7.87%~9.70% and 8.92%~10.75%,respectively). However, C.sinensis seed oil presented different MUFA(79.04%~81.17%) and PUFA(23.26%~27.86%). It showed that C15︰0, C20︰1,C22 ︰ 1, C18 ︰ 2n6, C22 ︰ 0 and C16 ︰ 0 were the characteristic fatty acid components for identifying the three oils.(3) There were 12, 10, and 13 unsaponifiable compounds in C.sinensis, C.oleifera,and C.camellia seed oils, respectively, including squalene and phytosterols. The total contents showed that the sequence was C.sinensis seed oil(5727.52 mg/kg) >C.camellia seed oil(5343.68 mg/kg) > C.oleifera seed oil(3939.40 mg/kg). In addition, 24-Methylenecycloartan-3-ol, β-stiosterol, spinasterol and β-amyrin were the characteristic unsaponifiable components for identifying the three oils.(4) There were 24, 22, and 24 phenolic compounds in C.sinensis, C.oleifera, and C.camellia seed oils, respectively, including phenolic acids, catechins, and flavonoids.Meanwhile, phenolic acids were the major compounds, whose percentage were76.2%~85.3%, 79.3%~88.3%, and 83.0%~90.4%, respectively. The total phenolic content showed that the sequence was C.sinensis seed oil(52.5631 μg/g) >C.camellia seed oil(48.1178 μg/g) > C.oleifera seed oil(28.2543μg/g).Epigallocatechin, quercetin, vanillic, apigenin, caffeic and gallic were the characteristic phenolic components for identifying the three oils.(5) The PCA and HCA presented that it was feasible to distinguish C.sinensis,C.oleifera and C.camellia seed oils based on the fatty acids, sterols, and phenolic compounds. It was presented that C15 ︰ 0, 24-methylenecycolartanol,epigallocatechin, C22 ︰ 1, quercetin, C18 ︰ 2n6, C17 ︰ 0, C20 ︰ 1, gallic acid,C22︰0, β-amyrin, C18︰1n9, vanillic acid, apigenin, and spinasterol were the most important variables for distinguishing three oils by random forest. At last,“Fancy Tiles” of whole compounds ID and characteristic compounds ID were established. They converted all data to figure and color, which described all compounds in oils not only qualitatively but also quantitatively. It was helpful in the distinction of Camellia seed oils and provided a new idea for authentic identification of other oils.