Investigation of some fixed oil chemical compositions in terms of omega-7

Omega-7 is a monounsaturated fatty acid, primarily known as palmitoleic acid. It is mainly found in plant and animal products such as macadamia nuts and buckthorn. Unlike essential fatty acids such as omega-3 and omega-6, omega-7s can be synthesized by the body. Omega-7 is known to improve skin health, support heart health by affecting lipid profiles, help weight management and have anti-inflammatory effects. Within the scope of the thesis, studies were carried out with sea buckthorn (fresh and dried fruits), which is rich in omega-7, and two different varieties of avocado (seed and pulp), Brazil nut (seed), Macadamia nut (seed) and Pecan nut (seed), which are tropical and have high nutritional value. The plant materials were subjected to extraction with apolar solvent (n-hexane) in the Soxhlet apparatus to obtain fixed oil. In the thesis, nine oils and commercial sea-buckthorn oil were methylated. After metillation their chemical compositions were determined by GC-FID and GC-MS methods. The fatty oils chemical profiles were elucidated, and their omega-7 content was evaluated. Oleic acid (43.5-64.7%) was detected as one of the main compounds in the oils obtained, except for the analyzed commercial oil. The oil yield of Macadamia nuts is 69.4% and contains 20% palmitoleic acid. When the oil contents of fruits that could be an alternative to buckthorn as a source of Omega-7 were evaluated, it was found that the richest fixed oil was obtained from Macadamia walnut's seed, followed by avocado pulp oil.