Analysis Of Nutritional Compositions And Preparation Of O/W Microemulsion Of Edible Trichosanthes Kirilowii Maxim. Seed Kernels

Conjugated fatty acids are a special class of polyunsaturated fatty acids (PUFA), the most common conjugated fatty acids are conjugated linoleic acid (CLA) and conjugated linolenic acid (CLNA). Researchers have confirmed that CLA has anti-cancer, body weight control, enhancing immunity and improving blood lipids and a series of benefitial physiological functions. CLA is a hot research topic currently. In the United States and Europe, CLA has been applicated broadly as a functional weight-loss supplement. Studies have also reported that CLNA has tumor cytotoxicity, inhibiting cancer formation and regulating lipid metabolism and a series of functions. CLNA can be converted to CLA in vivo, so it has aroused researchers' great interest.Trichosanthes kirilowii Maxim. (TK) seeds is rich in punicic acid (an isomer of CLNA) and is widely distributed in China. TK seeds has long been used as a traditional Chinese medicine, and it has also been used as a snack food. The aims of the dissertation were to investigate the nutritional compositions of TK seeds, and develop TK seed oil products.Part one: Nutritional compositions analysis of edible TK seed kernels from four origins in ChinaNutritional compositions of edible TK seed kernels from four origins of China were analyzed at the first time. The results showed that TK seed kernel was rich in protein ( 28.68 - 37.90 g/100g) and fat (26.15 - 49.41 g/100g), and also rich in Mg (2475.4 -3165.7 mg/kg), Cu (4.42 - 5.91 mg/kg), Fe (72.69 - 132.04 mg/kg), Mn (27.87 -49.84 mg/kg), Quzhou seed kernel was specially rich in Se (268.76μg/kg). TAG was the most abundant lipids of TK seed oil. The seeds were possessed 93.3% - 94.98% unsaturated fatty acids in total fatty acids. The three main fatty acids are punicic acid (an isomer of CLNA) with 33.09% - 39.15%, linoleic acid (C18: 2n-6) with 33.77% -38.66% and oleic acid (C18:1) with 15.76% - 25.46% of total fatty acids. TK seed contained 7.32 - 32.76 mg/100g total tocopherol. Big variation in nutritional compositions between origins maybe caused due to the differences of temperature, climate and soil conditions. As TK seed is the only edible source of CLNA, it has a potential to be developed as a functional food or nutraceuticals. Part two: Carbon dioxide supercritical extraction of TK seed oilThe CO₂ supercritical fluid extraction (CO₂-SFE) was used to extract the oil from TK seeds. Orthogonal experiment analysis was used to evaluate extraction pressure, temperature and time on the impact of the oil extraction rate. Suggested industrial extraction conditions was pressure 25 MPa and temperature 35℃for 1.5 h. Peroxide value of TK seed oil (2.25 mmol/kg) extracted with CO₂-SFE was lower than values of cold pressed soybean and caremella seed oil of GB1535-2003 and GB11765-2003. If the acid value was decreased, the overall quality of the oil would be increased. This part achieved to get large quantity of TK seed oil for oil in water (O/W) microemulsion development.Part three: OAV microemulsion development of TK seed oilThe OAV microemulsion of TK seed oil was developed, the microemulsion was uniform, stability, transparent and a little blue. Oil content was up to 3.3%, with an average particle diameter of 67.71 nm. However, the oxidative stability and bioavailability have not been studied in this thesis due to limited time.