As a member of nuts, walnut is consumed from snacks to salads and desserts to entrees and an importantpart of human diet for centuries. Walnut biological and nutritional value is also enhanced by its valuable protein ...As a member of nuts, walnut is consumed from snacks to salads and desserts to entrees and an importantpart of human diet for centuries. Walnut biological and nutritional value is also enhanced by its valuable protein and rich in nutrient composition such as vitamins and minerals. The most important characteristic of walnut oil is the abundance of polyunsaturated fatty acids, which makes it a unique food because of high amount of linoleic acid. Due to having valuable protein, vitamins and minerals it enhances biological and nourishment value, also. Recent epidemiological studies showed that consumption of walnut reduce cardiovascular diseases due to the rich in antioxidant properties, valuable fatty acids and tochopherols contents. In Turkey, walnut production and consumption increases year by year. The kernel of walnut genotypes shows variability in terms of their fat, fatty acid and tocopherol profiles. In this paper, it was aimed to characterize 10 walnut (Juglans regia L.) cultivars (Bilecik, Chandler, Hartley, Howard, Maras 12, Maras 18, Midland, Pedro, Sen and Serr) based on their fatty acid profiles using GC (Gas Chromatography), tocopherol and its isomers by HPLC (High Performance Liquid Chromatography) and total phenol content with spectrometric methods. Among the walnut cultivars “Hartley” was the highest linoleic acid (64.56%) and “Howard” was the α-linolenic acid 13.26 (%). The highest values of α (38.76 μg/g), β + γ (312.19 μg/g) and δ-tocopherol (40.77 μg/g) and total phenol (349 mg GAE/100 g ext) content were detected in “Sen” cultivar. Obtained results might be significant for further breeding programme to improve rich in especially γ-tocopherol linoleic acids and total phenolic compounds.展开更多
We systematically evaluated fatty acids and triacylglycerol composition,as well as tocopherol,phytosterol,and phenolics,in walnut oil and compared the cholesterol-lowering effects of oil processed with different metho...We systematically evaluated fatty acids and triacylglycerol composition,as well as tocopherol,phytosterol,and phenolics,in walnut oil and compared the cholesterol-lowering effects of oil processed with different methods(cold pressing,roast-pressing,hexane extraction,subcritical butane extraction,and supercritical CO_(2) extraction).The different methods did not affect the lipid composition of walnut oil.The tocopherol(41.11 mg/100 g)and total phenolic content(TPC,4.26 mg/100 g)of roast-pressed walnut oil and the phytosterol contents of subcritical butane-extracted walnut oil(106.51 mg/100 g)were higher than those of other tested oils.Walnut oil significantly decreased cholesterol synthesis by downregulating the expression of HMGCR,SREBP-2,and CYP51 genes,and increased cholesterol efflux by upregulating the expression of ABCG1,thus significantly reducing total cholesterol and triacylglycerol.Phytosterols and TPC in walnut oil were responsible for lowering cholesterol;the optimal concentration of phytosterols was 10μg/mL,and that of TPC was 12.5×10^(-3)μg/mL.Through process optimization,a new processing method for walnut oil based on biological evaluation was preliminarily established.展开更多
文摘As a member of nuts, walnut is consumed from snacks to salads and desserts to entrees and an importantpart of human diet for centuries. Walnut biological and nutritional value is also enhanced by its valuable protein and rich in nutrient composition such as vitamins and minerals. The most important characteristic of walnut oil is the abundance of polyunsaturated fatty acids, which makes it a unique food because of high amount of linoleic acid. Due to having valuable protein, vitamins and minerals it enhances biological and nourishment value, also. Recent epidemiological studies showed that consumption of walnut reduce cardiovascular diseases due to the rich in antioxidant properties, valuable fatty acids and tochopherols contents. In Turkey, walnut production and consumption increases year by year. The kernel of walnut genotypes shows variability in terms of their fat, fatty acid and tocopherol profiles. In this paper, it was aimed to characterize 10 walnut (Juglans regia L.) cultivars (Bilecik, Chandler, Hartley, Howard, Maras 12, Maras 18, Midland, Pedro, Sen and Serr) based on their fatty acid profiles using GC (Gas Chromatography), tocopherol and its isomers by HPLC (High Performance Liquid Chromatography) and total phenol content with spectrometric methods. Among the walnut cultivars “Hartley” was the highest linoleic acid (64.56%) and “Howard” was the α-linolenic acid 13.26 (%). The highest values of α (38.76 μg/g), β + γ (312.19 μg/g) and δ-tocopherol (40.77 μg/g) and total phenol (349 mg GAE/100 g ext) content were detected in “Sen” cultivar. Obtained results might be significant for further breeding programme to improve rich in especially γ-tocopherol linoleic acids and total phenolic compounds.
基金supported by the National Natural Science Foundation of China Youth Science Foundation Project(grant numbers 32001735).
文摘We systematically evaluated fatty acids and triacylglycerol composition,as well as tocopherol,phytosterol,and phenolics,in walnut oil and compared the cholesterol-lowering effects of oil processed with different methods(cold pressing,roast-pressing,hexane extraction,subcritical butane extraction,and supercritical CO_(2) extraction).The different methods did not affect the lipid composition of walnut oil.The tocopherol(41.11 mg/100 g)and total phenolic content(TPC,4.26 mg/100 g)of roast-pressed walnut oil and the phytosterol contents of subcritical butane-extracted walnut oil(106.51 mg/100 g)were higher than those of other tested oils.Walnut oil significantly decreased cholesterol synthesis by downregulating the expression of HMGCR,SREBP-2,and CYP51 genes,and increased cholesterol efflux by upregulating the expression of ABCG1,thus significantly reducing total cholesterol and triacylglycerol.Phytosterols and TPC in walnut oil were responsible for lowering cholesterol;the optimal concentration of phytosterols was 10μg/mL,and that of TPC was 12.5×10^(-3)μg/mL.Through process optimization,a new processing method for walnut oil based on biological evaluation was preliminarily established.