多种油脂的脂肪酸组成分析

制备出一种柱效高、成本低的复合型色谱柱。并利用醇解法进行了脂肪酸甲酯化，用气相色谱法测定了乌桕脂、棕榈油、可可脂、鱼油及自制类可可脂的脂肪酸组成。     

迎春花脂肪酸成分的GC/MS分析

采用乙醚提取迎春花脂肪酸,再经过甲酯化后,通过气相色谱/质谱联用技术分析脂肪酸的组成。共检出九种脂肪酸成分,主要成分分别为棕榈酸(29.27%)、亚油酸(19.75%)、二十碳三烯酸(16.63%)和十四(烷)酸(14.69%)。     

红树林内生真菌Paecilomyces sp.(Tree1-7)脂肪酸成分分析

采用φ(硫酸)=1%的甲醇溶液酯化法(方法1)和酸碱结合甲酯化法(方法2)分别对红树林内生真菌Paecilomyces sp.(Tree1-7)代谢产物的石油醚部位衍生化,用气相色谱-质谱法分析鉴定了其成分,测定了各成分的相对质量分数。两种方法鉴定出共有主要脂肪酸成分6种,分别为9,12-十八碳二烯酸、棕榈酸、硬脂酸、顺-9-十八碳烯酸、12-甲基-十四烷酸和Cyclopentaneundecanoic acid。其中9,12-十八碳二烯酸为红树林内生真菌Paecilomyces sp.(Tree1-7)石油醚部位的主要成分,其相对质量分数达56%以上。但两种方法所得微量脂肪酸种类存在差异,方法1共检测到13种,其中微量脂肪酸7种,而方法2能检测到17种,其中微量脂肪酸11种。与φ(硫酸)=1%的甲醇溶液酯化法相比,酸碱结合甲酯化法所得脂肪酸成分更为全面。     

乌桕梓油脂肪酸组成分析

乌柏是我国四大木本油料之一,种子含油量高,乌桕梓油是由种仁榨取所得的液体油脂,是轻工业、食品和国防等行业的重要油源。乌桕梓油甲酯化后,利用100 m×0.25 mm的GC毛细管柱,气相色谱法测定乌桕梓油的脂肪酸组成。测定结果表明：乌桕梓油中饱和脂肪酸占10.68%,以棕榈酸含量最高,占7.52%。不饱和脂肪酸占89.13%,单不饱和脂肪酸占18.63%,以油酸含量最高,占14.55%;多不饱和脂肪酸占70.50%;其中含量最高的为人体所必需的脂肪酸亚油酸和α-亚麻酸,分别占30.77%和39.30%。还含有相当数量天然植物中少有的奇数碳原子脂肪酸十一烷酸,占0.29%。其中月桂烯酸（占3.19%）和十一烷酸未见报道。     

番荔枝籽油脂脂肪酸组成的GC-MS分析

研究了番荔枝籽油脂中脂肪酸的组成.用索氏脂肪抽提器提取番荔枝籽的油脂,并以GC-MS分析油脂脂肪酸的组成.结果表明,番荔枝籽油脂收率达29.2％;番荔枝籽油脂中含有8种脂肪酸,主要为:油酸(45.37％)、亚油酸(30.68％)、棕榈酸(13.60％)和硬脂酸(8.94％),其中不饱和脂肪酸含量达76.29％.番荔枝籽含油量高,脂肪酸种类丰富,尤其是不饱和脂肪酸含量较高,具有较高的开发利用价值.     

GC-MS法分析两种辣蓼的脂肪酸成分

以湘西本地所采的两个品种的辣蓼为原料,通过对两种辣蓼的茎和叶分别进行索氏提取,再利用气相色谱-质谱联用仪分析鉴定其中的脂肪酸成分,研究不同种辣蓼的茎和叶部位的脂肪酸成分组成.因这两个品种的辣蓼在外观的颜色上有显著的差异,因此分别将它们命名为红辣蓼和白辣蓼来加以区分.结果共鉴定出10种脂肪酸成分结果表明:不同辣蓼所含有的...     

鲍鱼中脂肪酸的GC-MS分析

为了解鲍鱼中脂肪酸的组成,采用Bligh-Dyer法提取鲍鱼中的脂肪油,KOH-CH3OH溶液甲酯化后利用气相色谱-质谱联用仪进行分析测定。结果表明鲍鱼脂肪油中共检出脂肪酸11种,其中不饱和脂肪酸6种,相对百分含量为58.56%,棕榈油酸含量为2.31%,油酸的含量为22.79%,亚油酸含量为3.82%,5,8,11,14-二十碳四烯酸的含量为18.74%。     

气相色谱法分析椰子油的脂肪酸

本实验采用将椰子油与甲醇直接进行酯交换,取脂肪酸甲酯层进行色谱分析。文献[1]参考与实验证明,分析结果较为可靠,样品处理优于通常的皂化-酸化-甲酯化处理方式。用本方法和必要的分析条件,可较完整地分析椰子油和其它油脂的脂肪酸。     

两种不同酯化方法分析樱桃仁中的脂肪酸成分

以乙醚为溶剂,采用索氏抽提法提取樱桃仁粗脂肪油,分别用氢氧化钾/甲醇碱催化甲酯化法和N,O-二(三甲基硅烷)乙酰胺硅酯化法进行衍生化处理,通过气相色谱/质谱联用技术分析脂肪酸的组成。结果显示,粗脂肪油提取量24.6%,主要成分为亚油酸、油酸、棕榈酸、硬脂酸、亚麻酸以及二十碳二烯酸等,其中多不饱和脂肪酸占大部分,两种衍生化方法测得其总含量分别为79.21%和64.25%,三甲基硅酯化法是一种更全面的分析测定樱桃仁脂肪酸组成的衍生化方法。     

微生物细胞脂肪酸的组成分析

应用气相色谱—质谱联用技术(GC-MS)对微生物细胞脂肪酸的组成进行了分析.结果表明,菌体的代谢状态分为两个时期:菌体生长期和油脂积累期;菌体细胞主要积累油酸(C18:1)、软脂酸(C16:0)和棕桐油酸(C16:1);通过发酵,最终得到的微生物油脂脂肪酸组成为:油酸(C18:1)64.80％、软脂酸(C16:0)19...     

Fatty Acid Composition of Freshwater Wild Fish in Subalpine Lakes: A Comparative Study

In this study, the proximate and fatty acid compositions of the muscle tissue of 186 samples of fish belonging to fifteen species of freshwater fish harvested in subalpine lakes (bleak, shad, crucian carp, whitefish, common carp, pike, black bullhead, burbot, perch, Italian roach, roach, rudd, wels catfish, chub and tench) were investigated. Most of the fish demonstrated a lipid content in the fillet lower than 2.0 g 100 g^?1 wet weight (range 0.6–9.7). A strong relationship between feeding behavior and fatty acid composition of the muscle lipids was observed. Planktivorous fish showed the lowest amounts of n‐3 fatty acids (p < 0.05), but the highest monounsaturated fatty acid (MUFA) contents, in particular 18:1n‐9. Conversely, carnivorous fish showed the highest amounts of saturated fatty acids and n‐3 fatty acids (p < 0.05), but the lowest MUFA contents. Omnivorous fish showed substantial proportions of n‐3 fatty acids and the highest contents of n‐6 fatty acids. Principal component analysis showed a distinct separation between fish species according to their feeding habits and demonstrated that the most contributing trophic markers were 18:1n‐9, 18:3n‐3, 22:6n‐3 and 20:4n‐6. The quantitative amounts n‐3 polyunsaturated fatty acid in muscle tissues varied depending on the fish species, the lipid content and the feeding habits. Some species were very lean, and therefore would be poor choices for human consumption to meet dietary n‐3 fatty acid requirements. Nevertheless, the more frequently consumed and appreciated fish, shad and whitefish, had EPA and DHA contents in the range 900–1,000 mg 100 g^?1 fresh fillet.     

Lipid Content and Fatty Acid Profile of Muscle,Brain and Eyes of Seven Freshwater Fish: a Comparative Study

The fatty acid and lipid content of the eyes, brain and muscle were determined for the following seven freshwater fish species in China: black carp, grass carp, silver carp, bighead carp, common carp, crucian carp, and Wuchang bream. Lipid contents of all seven freshwater fish were in the order of brain > eyes > muscle. Most of the freshwater fish demonstrated much lower n-3 PUFA than n-6 PUFA in all tissues with n-3/n-6 ratios varying between 0.07 and 0.40, while silver carp and bighead carp had much higher n-3 PUFA than n-6 PUFA. The percentage of PUFA in the muscle of all species are the highest compared to those of the eyes and brain, while no significant difference was observed in PUFA concentration between eyes and brain (p > 0.05). Multivariable analyses indicate that the fatty acid composition of the filter-feeder fish (silver carp and bighead carp) was distinct from the other four species.     

Seasonal Variations in Lipid Content,Fatty Acid Composition and Nutritional Profiles of Five Freshwater Fish from the Amazon Basin

Fish from the Amazon Basin are affected by oscillations in the river water volume, which influences the diet of animal species. This study was aimed at evaluating seasonal variations in lipid content, fatty acid composition and nutritional profiles of five fish species from the Amazon Basin. The lipid contents of all fish species were observed to be lower in flood periods than in drought periods; Brachyplatystoma flavicans showed the largest variation (6.75–15.43 %) between these periods, while Colossoma macropomum showed no significant difference (p > 0.05). The fatty acid composition in the five fish species varied throughout seasonal periods; saturated fatty acid (SFA) contents decreased in flood periods, whereas polyunsaturated fatty acid (PUFA) contents significantly (p < 0.05) increased for all the species in the same period. Leporinus friderici showed the highest content of α‐linolenic acid, (LNA 14.86 mg g^?1) and Colossoma macropomum presented the highest content of docosahexaenoic acid (DHA 26.13 mg g^?1) in flood periods. Prochilodus nigricans showed the lowest content of arachidonic acid (AA) in both periods, while Brachyplatystoma flavicans showed the greatest amount of AA, 18.77 mg g^?1 in drought period and 22.10 mg g^?1 in flood period. All the fish species presented favorable indices of nutritional quality of lipid fraction, suggesting that consumption of these species could be considered beneficial to human health.     

Fatty Acid Composition of Tropical Fish Depends on Reservoir Trophic Status and Fish Feeding Habit

Eutrophication results in a deficiency of n‐3 LC‐PUFA (long‐chain polyunsaturated fatty acids) in aquatic food chains, affecting fish nutrition and physiology. The trophic transfer of FA (fatty acids) to fish species of different feeding habits was investigated in two reservoirs in southeast Brazil—the mesotrophic Ponte Nova Reservoir (PN) and the hypereutrophic Billings Reservoir (Bil). Total FA profile of stomach contents and adipose tissue, triacylglycerols (TAG), and phospholipids (PL) from liver and muscle of the omnivorous Astyanax fasciatus and the carnivorous Hoplias malabaricus were analyzed by gas chromatography. A prevalence of n‐6PUFA, as 18:2n‐6 (linoleic acid) and 20:4n‐6 (arachidonic acid, ARA) was observed in the stomach contents and in the tissues of A. fasciatus from the PN reservoir. In contrast, n‐3 LC‐PUFA, as 20:5n‐3 (eicosapentaenoic acid, EPA) was accumulated in fish tissues from Bil, resulting in higher n3/n6 and EPA/ARA ratios, compared to fish from PN. This differential FA accumulation was also observed for H. malabaricus, but differences were slightly minor, and no changes were observed in the EPA/ARA ratios between fish from both reservoirs. Regardless reservoir, FA profiles of TAG resembled that of their diet, whereas FA profiles of PL were more conservative and mainly comprised by LC‐PUFA. We conclude that reservoir trophic status affected the FA composition of food resources available to these fish species, resulting in differential allocation of n‐3 and n‐6 FA. As expected, FA profile of the investigated fish species also reflected their feeding habit and physiological demands.     

Nutritional Value of Seven Freshwater Fish Species From the Brazilian Pantanal

This study determined the proximate composition and fatty acid profile of the lipid fraction in muscle tissue (fillet) of seven fish species from the Miranda River, Brazil. Total lipid content had the largest coefficient of variation among species (73%), while protein content had the smallest (4.5%), allowing Pimelodus argenteus (mandi-prateado) to be categorized as lean fish; Pimelodus maculatus (mandi-amarelo), Hemisorubim platyrhynchos (jurupoca), and Pinirampus pirinampu (barbado) as species with medium fat content, and Paulicea luetkeni (jaú) and Surubim lima (jurupensém) as fatty fish. In all the species investigated, palmitic acid (23.76–25.99%) was the predominant saturated fatty acid. Oleic acid (16.09–32.90%) was the most abundant monounsaturated fatty acid. Total omega-6 polyunsaturated fatty acids (5.99–15.56%) were the predominant polyunsaturated fatty acids, except in Ageneiosus brevifilis (palmito), in which total omega-3 polyunsaturated fatty acids predominated (10.30%). All the species had favorable indices of nutritional quality for total lipids, with respect to human consumption.     

Fatty Acid Composition and Contents of Seven Commercial Fish Species of Genus <Emphasis Type="Italic">Coregonus</Emphasis> from Russian Subarctic Water Bodies

In several Russian northern lakes and rivers, Arctic cisco Coregonus autumnalis, least cisco C. sardinella, peled C. peled, tugun C. tugun, broad whitefish C. nasus, whitefish C. lavaretus and vendace C. albula were sampled in periods of officially permitted commercial fishery. Special attention was paid to contents (mg g^?1 of wet weight) of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in muscle tissues (filets), which are essential for human nutrition. The highest values of EPA + DHA content in semi‐anadromous fish and freshwater fish were recorded for C. autumnalis from the Yenisei River, 17.60 mg g^?1 wet weight, and for C. lavaretus from the Sobachye Lake, 16.61 mg g^?1 wet weight, respectively. Intra‐genus variations of EPA + DHA contents of Coregonus species were from 1.87 to 17.60 mg g^?1 wet weight. Since the congeneric species were genetically close to each other, the variations in EPA and DHA contents were thought to be caused primarily by ecological factors: migrational capability, type of feeding and trophic status of aquatic ecosystems. In general, the majority of studied species appeared to be of a high nutritive value for humans, although unfavorable environmental conditions could considerably diminish this value.     

环氧油脂肪酸组成分析研究

通过薄层色谱、气相色谱、色质联用等技术,首次得到了油脂环氧化反应期间的脂肪酸环氧化反应规律:开始反应阶段,高含量不饱和脂肪酸反应速率高于低含量不饱和脂肪酸;环氧化反应期间,多不饱和脂肪酸首先生成单环氧酸,之后再逐渐生成二环氧酸,最后生成三环氧酸;富含亚麻酸的油脂环氧化反应时有更易于开环反应的趋向,其次是富含亚油酸的油脂,再次是富含油酸的油脂.实验结果表明,不同环氧油原料在进行环氧化反应时需要控制不同的反应条件,以避免开环副产物量的增加,从而制备得优质环氧油产品.     

灵芝孢子油脂肪酸组分分析

脂肪酸含量差异是目前油种真伪鉴别的主要方法,采用气相色谱(GC)法对灵芝孢子油脂肪酸组分进行了分析。结果显示:灵芝孢子油中检出15种脂肪酸,其中饱和脂肪酸占22.931%,主要为棕榈酸(15.729%)、硬脂酸(3.734%)和十七碳酸(1.402),不饱和脂肪酸占76.977%,主要为油酸(63.027%)和亚油酸(12.809%)。同时对市售5个不同品牌灵芝孢子油(100%)软胶囊中油的脂肪酸组分进行了分析,发现其脂肪酸组成及含量比较接近,棕榈酸、十七碳酸、硬脂酸、油酸和亚油酸含量占95%以上,其中棕榈酸平均含量为15.181%,十七碳酸平均含量为1.423%,硬脂酸平均含量为3.722%,油酸平均含量为63.444%,亚油酸含量为13.189%。