Comparison the nutritional value of cultured Penaeus vanname with marine shrimps Penaeus merguiensis and Penaeus semisulcatus

The purpose for which this study was intended wasto compare nutritive value among the farmed Vannamei, sea Green Tiger and Banana shrimps native to the PersianGulf. To provide the samples of farmed shrimps at the end of the farming season (Oct. 23rd through Nov. 22nd of 2011), we chosen one farm of the Holleh Shrimp Farming, from which 100 shrimps were randomly selected. From among these 100 shrimps, 3 to 5 ones were taken to conduct an analysis upon. Further, to obtain the Banana and Green Tiger shrimps sampling was done at the fishing season (July 23rd through Aug. 22rd of 2011) at Halileh Fishing Wharf located in Bushehr Fishing Harbor and also Bandar Abbas Wharf. The samples obtained were immediately kept in the ice powder. After some biometric tasks done upon them, they were at the shortest possible time transferred to a laboratory where they went through various experiments to determine their content of raw protein, fat, ash, moisture, various fatty acids and their types, cholesterol, vitamins A and E, and such mineral elements as iron and calcium. All the experimentswere carried out three times to establish confidence in the results to be obtained. Findings of the comparison showed the content of raw protein, fat, moisture, and ash of, respectively, 23.233%, 600%, 73.077% and 2.500% for the Vannamei samples, of 22.717%, 427%, 74.133% and 1.826% for our Banana shrimps and of 17.377%, 430%, 79.866% and 1.313% for the Green Tiger samples. A total of 24 fatty acids for the Vannamei shrimps and 27 for the Banana and Green Tiger were detected. SFA of the Banana shrimps was 368.45 mg/100g (51.76%), while those of the Vannamei and Green Tiger samples were observed, respectively, 363.54 mg/100g (37.26%) and 296.06 mg/100g (49.12%).A similar measurement for MUFA content of the three types of our samples revealed 243.85mg/100g (24.9%) for the Vannamei, 203.177 mg/100g (33.76%) for the Green Tiger and 179.033 mg/100g (25.14%) for the Banana shrimps. The content of PUFA unsaturated fatty acids in the Vannamei, 131 Green Tiger and Banana samples were, respectively, 370.660 mg/100g (37.84%), 101.573 mg/100g (16.9%) and 163.733 mg/100g (23.1%). Further, the comparison found a omega-3-fatty-acids total of 151.747 mg/100g(15.51%) for the Vannamei, 57.123 mg/100g (9.54%) for the Green Tiger and 130.460 mg/100g (18.46%) for the Banana species under study.

Determination of proximate composition, shelf life and fatty acid profiles of breaded kilka (Clupeonella cultriventris) during frozen storage

The present study aimed production of a new product with various texture and sensory properties in chase of the impetus for increasing human consumption considering suitable resources of Kilka fish in Caspian Sea. Following deheading, gutting, and brining, common Kilka were battered in two different formulations, i.e. simple batter and tempura batter, via automated predusting machinery and then, they were fried through flash frying for 30 seconds at 170°C in sunflower oil after they were breaded with bread crumbs flour. The products were subjected to continuous freezing at -40°C and were kept at -18°C in cold storage for four months once they were packed. Chemical composition (protein, fat, moisture, and ash), fatty acid profiles (29 fatty acids), chemical indices of spoilage (peroxide value, thiobarbituric acid, free fatty acids, and volatile nitrogen), and microbial properties (total bacteria count and coliform count) were compared in fresh and breaded Kilka at various times before frying (raw breaded Kilka), after frying (zero-phase), and in various months of frozen storage (phases 1, 2, 3, and 4). Organoleptic properties of breaded Kilka (i.e. odor, taste, texture, crispiness, cohesiveness of batter) and general acceptability in the phases 0, 1, 2, 3, and 4 were evaluated. The results obtained from chemical composition and fatty acid profiles in common Kilka denoted that MUFA, PUFA, and SFA were estimated to be 36.96, 32.85, and 29.12 g / 100g lipid, respectively. Levels of ù-3 and ù-6 were 7.6 and 1.12 g / 100 gr lipid, respectively. Docosahexaonoic acid (20.79%) was the highest fatty acid in PUFA group. ù-3/ù-6 and PUFA/SFA ratios were 7.6 and 1.12, respectively. The high rates of the indices and high percentage of ù-3 fatty acid in common Kilka showed that the fish can be considered as invaluable nutritional and fishery resources and commonsensical consumption of the species may reduce the risk of cardiovascular diseases. Frying breaded Kilka affected overall fat and moisture contents so that moisture content in fried breaded Kilka decreased significantly compared to raw breaded Kilka, while it was absolutely reverse for fat content. Overall fat content in tempura batter treatment was significantly lower than that of simple batter treatment (P≤0.05). Presence of hydrocolloids, namely proteins, starch, gum, and other polysaccharides, in tempura batter may prohibit moisture evaporation and placement with oil during frying process in addition to boosting water holding capacity through confining water molecules. During frying process, fatty acids composition of breaded Kilka with various batters changed so that rates of some fatty acids such as Palmitic acid (C16:0), Stearic acid (C18:0), Oleic acid (C18:1 ù-9cis), and linoleic acid (C18:3 ù-3) increased considerably following frying; however, ù-3/ù-6, PUFA/SFA, and EPA+DHA/C16:0 ratios (Polyan index) decreased significantly after frying. ù-3/ù-6, PUFA/SFA, and EPA+DHA/C16:0 ratios in tempura batter treatment were higher than those of simple batter treatment which is an indicator of higher nutritional value of breaded Kilka with tempura batter. Significant elevations were found in peroxide, thiobarbituric acid, and free fatty acids in fried breaded Kilka samples compared to raw samples which points to fat oxidation during cooking process. Overall microorganism count and coliform count decreased following heating process. Both breaded Kilka samples were of high sanitation quality at zero-phase according to ICMSF Standard. The results acquired from organoleptic evaluation declared that odor, cohesiveness, and general acceptability indices, among others, had significant differences between the treatments (P≤0.05). In all evaluated properties, breaded Kilka with tempura batter in different phases gained higher scores than breaded Kilka with simple batter. During cold storage of various treatments of breaded Kilka, total lipid content, PUFA, MUFA, ù-3, ù- 3/ù-6, PUFA/SFA, Polyen index decreased significantly. The mentioned reductions in addition to significant elevation of spoilage indices, namely peroxide, thiobarbituric acid, and free fatty acids, during frozen storage, indicate to oxidation and enzymatic mechanism activity during frozen storage of breaded Kilka. Considering sensory evaluation at the end of the fourth month and TVB-N contents exceeded eligible rate in the fourth month, shelf life of the products during frozen storage was set to be three months at -18°C. The results obtained from statistical tests indicate to better quality of breaded Kilka processed with tempura batter compared to simple batter in terms of organoleptic evaluation, spoilage indices, and high quality of fat in various sampling phases.

Effects of the quick and slow freezing on the quality of Nile Tilapia fillets (Oreochromis niloticus) and Red Tilapia fillets (O. niloticus and Tilapia mosambicus)

In this study, quality of fresh, slow frozen and quick frozen tilapia fillets and its changes during storage at -18C° were investigated. For preparation the samples, fresh tilapia fillets were frozen by slow and quick frozen methods. Slow frozen samples were prepared by storing the packed fillets directly in the -18 C°. The sprila freezing tunle with -30C° was also used for preparation the quick frozen sample. The quick frozen samples were then stored at -18C°for six months. Proximate composition, fatty acid profiles, TBA, PV, TVN, Total cuont, Drip loss, and sensory evaluation of the samples were determined in every month. Scanning Electron Microscopy (SEM) was used for study on the effects of the frozen condition on the microstructure of the fillets. Results indicated that two different frozen methods had significantly different effects on the quality of the fillets. Most of the proximate composition (protein, moistre and fat) reduced during the storage. Quick frozen filets had significantly (P<0.05) lower reduction than slow frozen samples. All of the chemical quality indexes (PV, TBA, and TVN) increased during the storage as compered to the fresh samples. In these paramethers, the slow freezing had higher changes than quick freezing metods (P<0.05). The microbial properties of the samples showed decrese during the storage. Lower amont of total cuont was observed at the end of the storage time in the quick frozen samples than slow frozen once (P<0.05). The large changes in the fatty acid profiles of the sample were fond in all samples. During the storage SFA and MUF of the samples increased however, the PUFA decresed. A lower change was obseved in the quick frozen samples than slow frozen samples (P<0.05). Drip loss was increased in both frozen samples during the storage period. The percentage of the drip in the slow frozen samples was significantly higer than quick frozen samples (P<0.05). SEM micrographs were also showed that the chnges in the microstructur of the samples was different in the slow and frozen samples. Slow freezing methods had higher damge in the microstructure of the sample then quick freezing mathods. Sensory evaluation of the samples indicated that a better acceptability in the quick frozen samples than slow frozen sample (P<0.05).

Effect of thawing methods on the chemical, biochemical, microbiological and sensory indices of Caspian Sea kutum (Rutilus frisii kutum) and rainbow trout (Oncorhynchus mykiss)

Effects of different thawing method i.e. in a refrigerator, in water, at air ambient temperature and in a microwave oven on proximate, chemical (PV, TBA, FFA, TVB-N, SSP, FA), biochemical (pH, WHC,ThL), microbial (total viable, psychrotrophic, coliform, Shewanella and yeast-mould count) and sensory analysis were carried out on frozen whole Caspian sea Kutum (Rutilus frisii kutum) and Rainbow trout (Oncorhynchus mykiss) carcasses. The values of ash, protein, SSP, WHC, PUFA, PUFA/SFA. EPA+DHA/C16:0, pH, and microbial count of thawed samples decreased significantly while fat, PV, TBA, FFA, TVB-N, SFA and MUFA increased compared to the fresh fish (unfrozen) as control samples. Also, sensory evaluation all of thawed samples showed a significant (p<0.05) quality loss compared to the fresh fish as control samples. The lowest chemical and biochemical values as well as microbial growth were determined in water thawed samples. Therefore, based on this study thawing in water is most suitable for frozen whole rainbow trout.

Identification and measurement of fatty acids, amino acids in roe of tuna fish (Thunnus tonggol) and its TVB and peroxide value during cold storage

The first aim of this research was to identify fatty acids, amino acids composition of Thunnus tonggol roe and their changes during cold storage (-18'C). The second aim was to determine the changes of moisture, protein, fat and ash contents of the roe during one year cold storage (-18'C). 60 samples of longtail tuna (Thunnus tonggol) ovaries were randomly collected form Bandar-e-Abbas landings. The samples were frozen at-30'C and kept in cold store at -18'C for one year. According to a time table, the samples were examined for identification of fatty acids, amino acids, moisture, protein, fat, ash, peroxide and T.V.N. and their changes were evaluated during this time. The results showed that 26 fatty acids were identified. The unsaturated fatty acids (UFA) and saturated fatty acids (SFA) were 62.33 and 37.6%, respectively, in fresh roe. So that, DHA (C22:6) and oleic acid (C18:1) had high amounts (24.79 and 21.88%) among the UFA and palmitic acid (C16:0) was the most content (22.75%) among the SFA. The PUFA/SFA was 0.91. Also, 17 amino acids were identified that essential amino acids (EAA) and nonessential amino acids (NE) were 10478 and 7562 mg/100g, respectively, and E/NE was 1.38. Among the EAA and NE, lysine (2110mg/100g) and aspartic acid (1924 mg/100g) were the most contents. Also, results showed that moisture, ash, protein and fat contents were 72.74, 1.8, 19.88 and 4.53%, respectively, in fresh roe. The effects of freezing and cold storage on the roes showed that UFA and SFA contents have reached to 49.83 and 48.07%, respectively, at the end of cold storage. It indicated that these compounds change to each other during frozen storage. Also, n-3 and n-6 series of fatty acids were 32.75 and 1.61% in fresh roe. But their contents decreased to 22.96 and 1.25% at the end of period. Among the fatty acids, 22:6 and C16:0 had the most changes. The changes of fatty acids were significantly at 95% level except for C15:1, C18:3(n-3) and C20:4(n-6). All of the amino acids decreased in frozen storage and their changes were significantly (P<0.05). EAA was 7818 mg/100g and E/NE was 1.27 at the end of storage period. Among the amino acids, leucine and lysine had the most changes. Moisture, ash, protein and fat contents were 70.13, 1.82, 19.4 and 6.51%, respectively, at the end of storage period. The peroxide value and T.V.N. increased during storage. So that, their contents have reached to 5.86 mg/kg and 26.37 mg/100 g, respectively, at the end of frozen storage. The best shelf life of Thunnus tonggol roe was 6 or 7 months, because of lipid oxidation and increasing of peroxide.

Quantative and qualitive identification of the fatty acids in the mullet (Liza aurata), sever juga (Acipenser stellatus) and Persian sturgeon (A. persicus), considering of cold storing effects on them

At the fishing season, in 2000, samples of species persian sturgeon (A. persicus), Severjuga (A. stellatus) and Mullet (L. aurata), were caught from the southern coasts of Caspian Sea and were freezes and preserved in the cold storage for one year They have also become biometery. The tissue's fillet were identified in order to determined the Fatty Acids. This was done during one year, frequently, fresh, two weeks after freezing and then monthly, respectively. So, after the extraction of lipids from the tissues and methylation, was injected to the gas-liquid Chromatography. After calibration, identified Fatty Acids were compared with standards according to their Retention Times. Peroxid value, lipid content and humidity were controlled. The unsaturated Fatty acids had The most amount, and a plenty of Polyunsaturated Fatty acids (PUFA) were observed, so that linoleic (C18:2), a-linolenic (C18:3), Arashidonic (C20:4), EPA (C20:5) and DHA (C22:6) Fatty acids had high amounts. The w-3, PUFA were more in comparison with w-6. The effects of freezing and cold storing on the fish fatty acids , were evaluated by the statistical tests , like SPSS, Tukey, Homogenous and Anova, and showed that in some species, a group of Fatty acids, specially PUFA, had some variation. The peroxide value that indicates the lipid deterioration, increased during toring. So, the best term if preserving in the cold storage, were determined and their Nutrition value and Medical applications due to their consumption were investigated.

鲢早期发育阶段鱼体脂肪酸组成变化

用气相色谱仪分析了鲢受精卵和仔鱼的脂肪酸组成及其变化。受精卵中共检测到 1 9种脂肪酸 ;SFA含量最高 ,其次为 PUFA,MUFA最少。 SFA中以 1 6 C∶ 0为主 ,MUFA中以1 8C∶ 1为主 ,PUFA中以 DHA、AA和 EPA为主 ;n- 3 /n- 6为 2 .45。初孵仔鱼中 HUFA因卵膜的脱落而减少 ,以后逐渐积累 ;鲢仔鱼具有将 1 8C PUFA转化为长链 HUFA的能力 ;在早期发育阶段 ,鲢仔鱼主要消耗 1 6 C∶ 0作为能量代谢的基质。

稀有鮈鲫的脂肪酸组成

稀有鲫汉源种群和彭州种群全鱼中共检测到 3种饱和脂肪酸 (SFA) ,它们是C1 4∶0、C1 6∶0、C1 8∶0。 4种单不饱和脂肪酸 (MUFA) ,它们是C1 4∶1、C1 6∶1、C1 8∶1、C2 0∶1。 4种多不饱和脂肪酸 (PUFA) ,它们是C1 8∶2、C2 0∶4、C2 0∶5 (EPA)、C2 2∶6 (DHA)。SFA占总脂肪酸的2 3 6 3— 2 8 97% ,MUFA占 40 73— 5 4 3 2 % ,PUFA占 9 96— 2 3 1 7% ,EPA占 0 41—

海洋动植物中不饱和脂肪酸的研究

不饱和脂肪酯是人及动物生长发育的必需物质。本论文分析了海洋动植物脂和脂肪酸的组成，并对不饱和脂肪酸的分离提纯方法进行了研究。一、海洋动植物的中性脂主要包括三酰甘油和胆固醇。动物极性脂主要为磷脂，包括磷脂酰丝馆酸（PS）、磷脂酸（PA）、磷脂酰肌醇（PI）、溶解性磷脂酰乙醇胺（LPE）、神经鞘磷脂（CAEP）、磷脂酰胆碱（PC）、磷脂酰乙醇胺（PE），双磷脂酰甘油（DPG）。其中LPE、DPG为动物所特有的磷脂。植物极性脂包括PI、PC、PE、双半乳糖苷地酰甘油酯（DGDG）、硫代6-脱氧葡萄糖苷二酰甘油酯（SQDG）、单半乳糖苷二酰甘油酯（MGDG）、磷脂酰甘油（PG）及植物脑苷脂（Plant Cerebrosides）。其中MGDG、DGDG、SQDG为植物所特有的三种糖脂。二、海洋动植物含有丰富的不饱和脂肪酸，多聚不饱和脂肪酸（PUFA）含量尤为显著。灰凹贻贝（Crenomythilus graiaynus）的二十碳五烯酸（EPA）含量为10.6%,二十碳四烯酸（AA）为3.7%，二十二碳六烯酸（DHA）为14.26%。中间球海胆（Strongylocentrotus intermedius）的AA含量为7.36%，EPA为15.98%。内枝多管藻（Polysiphonia morroωii)PUFA含量非常高，AA占2.43%，20:4ω3占4.97%，EPA占45.03%。裙带菜（Undaria pinnatifida）的PUFA中，十八碳二烯酸占6.16%，AA占12.99%，EPA占7.83%这些PUFA大都为人及动物生长发育的必需脂肪酸。三、尿素诱导法是大量提取混合PUFA的有效方法。在产品中，饱和脂肪酸的含量可以忽略不计，单烯脂肪酸含量降低很多；高吸附能力的柱层析是提取PUFA单体的较好方法，其产物的纯度达98%以上。

海洋单细胞藻中脂类和高度不饱和脂肪酸的研究

本项研究比较了我国海水养殖中常用的几种单细胞藻的脂类和脂肪酸组成，并从中选出球等鞭金藻3011，进一步研究环境因子对其总脂和DHA含量的影响，并研究单细胞藻中脂类和PUFAs向浮游动物卤虫传递的趋势。研究发现：这几种单细胞藻的总脂含量大部分相当高，而且总脂中的极性脂和n-3系列的PUFAs含量都很高，但其组成和含量在不同藻中有很大差别。在不同季节和不同盐度条件下培养金藻3011，发现总脂中DHA的含量随温度的升高而降低；盐度过高或过低都阻碍金藻3011的生长速度并降低单位体积脂肪和DHA的产量，但并不明显影响每个细胞中总脂和PUFA的含量；通过对单细胞藻中的n-3PUFAs和浮游动物卤虫传递的实验研究，发现单细胞藻中不同的PUFAs其递情况有很大差别，另外，不同藻类中的同种PUFAs向卤虫传递的效果也不同。

大西洋庸鲽Hippoglossus hippoglossus和大西洋鲑Salmo salar配子质量研究

种质问题是养殖健康发展的基础。在鱼类养殖中，卵子和精子的质量直接关系到受精、胚胎发育，仔稚鱼发育以及幼鱼生长等一系列过程。本论文针对大西洋庸鲽和大西洋鲑的配子质量进行研究。研究内容涉及大西洋庸鲽精子冷冻保存方法；促性腺激素释放激素类似物（GnRHa）使用对其精子冷冻保存效果、以及脂肪酸组成的影响；野生和驯养大西洋鲑卵子在脂肪酸、类胡萝卜素、矿物盐方面的差异比较。 精子冷冻保存通过提高对精子的利用效率，进而对于种质改良，推进鱼类养殖科研和生产具有重要意义。本实验建立了大西洋庸鲽精子大容量冷冻保存方法。八种抗冻剂冷冻保存实验结果表明：10% 及15% DMSO配以 HBSS 或KS 的抗冻剂组合冷冻保存效果最佳，4 mL体积冷冻保存可获得与1.6 mL同样的保存效果。 在繁殖季节后期注射GnRHa激素缓释剂，可获得质量稳定的大西洋庸鲽精液，将激素注射方法与精子冷冻保存方法相结合对于提高雄鱼利用率，扩大生产规模具有重要实用价值。本项研究分三个时间采集注射GnRHa激素后的雄鱼精子以及同期未注射激素的雄鱼精子，对所有精子样品使用同样的方法进行冷冻保存，检测冷冻保存后解冻精子的受精率与活力。结果表明，激素注射与否对于冷冻保存后精子的受精率和活力无显著影响，两类冷冻精液均达到鲜精水平。实验结果还表明，注射激素14天后的精子的密度显著的降低。说明GnRHa激素的使用可以显著降低精子密度，但不会影响精子的冷冻保存效果。 本相研究同时对注射GnRHa 缓释激素和未注射GnRHa 缓释激素的大西洋庸鲽精液脂肪酸成分进行分析，以检测该激素使用对精子生化组分的影响。结果表明激素的使用对在DHA (22:6n-3,二十二碳六烯酸)、EPA(20:5n-3,二十碳五烯酸)、AA(20:4n-6，花生四烯酸)等重要脂肪酸，不饱和脂肪酸、饱和脂肪酸以及n-3、n-6等重要种类的脂肪酸总量及其比例没有显著影响。精液脂肪酸中DHA含量最高，约占25%；PUFA约为44%。 作为世界性的重要养殖品种，野生和驯养大西洋鲑在形态、生化组成以及遗传 等方面表现出的差异被广泛关注。本论文，对野生和驯养大西洋鲑受精卵关键生化成分进行分析，通过与野生受精卵比较阐明驯养受精卵的质量状况，为亲鱼营养需求提供指导依据。本实验中野生配子和驯养配子的受精率没有显著差异，但重要脂肪酸组成、类胡萝卜素以及矿物盐含量都存在多方面显著差异。两类受精卵脂肪酸中含量最高的依次为18:1n-9（油酸）、DHA（二十二碳六烯酸）、16:0（棕榈酸）、EPA（二十碳五烯酸）。野生受精卵的单不饱和脂肪酸总量显著高于驯养受精卵，而多不饱和脂肪酸（PUFA）比例显著低于驯养的受精卵。在主要必需不饱和脂肪酸（EFA）中，DHA和EPA在野生受精卵中的比例高于驯养受精卵，AA（花生四烯酸）低于驯养受精卵。野生受精卵虾青素（Ax）的含量低于驯养受精卵而鸡油菌素（Cx）含量高于驯养受精卵。野生受精卵中多种矿物盐的含量（铝、铜、铁、硒和锌）含量显著高于驯养的受精卵。差别最大的为铜。诸多方面的差异表明，野生亲鱼与驯养亲鱼产出的卵子确实存在显著差异，因此关注亲鱼的营养极为重要。

刺参Apostichopus japonicus营养成分、食物来源及消化生理的季节变化

本文从消化生理学角度出发，研究了刺参营养成分、食物来源以及消化道结构与功能的季节变化，并对养殖水温对刺参消化道结构与功能的影响及与夏眠之间的关系进行了探讨。主要研究结果如下： 1.较为系统地评述了我国刺参增养殖业的现状及存在的问题；对海参的营养成分研究进行了综述和展望；对刺参的消化生理及其夏眠的研究进行了综述并提出了新见解和思路。 2.研究了刺参体壁营养成分的季节变化（2006年7月-2007年6月）。结果表明刺参体壁的基本营养成分及氨基酸、脂肪酸的含量具有显著的季节变化；氨基酸组成全面，平均氨基酸得分（AAS）在75.79-85.17之间，其中8月最高，1月最低；脂肪酸种类丰富，饱和脂肪酸（SFA）相对含量季节变化显著，8月份最高，1月份最低；单不饱和脂肪酸（MUFA）季节变化不显著；多不饱和脂肪酸（PUFA）相对含量具有明显的季节变化，其变化规律与SFA相反，8月份最低，1月份最高；综合分析表明刺参的营养价值在冬季的11月、1月最高。 3.用脂肪酸标志法分析了刺参食物来源组成情况及季节变化（2006年7月-2007年6月）。1月份刺参的主要食物来源是硅藻、鞭毛藻或原生动物、褐藻以及细菌（变形细菌和革兰氏阴性菌），3月份是硅藻、鞭毛藻或原生动物和大型绿藻。6月份大型绿藻在刺参的食物来源中占据较大比重。7月份细菌（噬纤维菌-黄杆菌类、革兰氏阳性菌）和大型绿藻的食物贡献较大。细菌（噬纤维菌-黄杆菌类、革兰氏阳性菌）在8、9月份的食物来源中占较大比重。褐藻和细菌（变形细菌和革兰氏阴性菌）在10、11月的食物贡献较大。 4.现场研究了刺参消化道和消化酶活性的季节变化（2006年6月到2007年6月）。结果表明：刺参的消化酶活性和消化道性状指标均有显著的季节变化。典型夏眠期的9月份，刺参的相对消化道重量（RGM）和Zihler’s 指数分别降低到全年最高值的8.2% 和28.0%。夏眠期间刺参的消化道指数与淀粉酶、脂肪酶、胰蛋白酶、纤维素酶、褐藻酸酶活性都很低，但胃蛋白酶活性很高，且远高于非夏眠期；分析表明Zihler’s指数可以反应刺参的食性，而相对RGM则可反应刺参的摄食状况。 5.研究了养殖水温（7°C、14°C、21°C、28°C，40天）对刺参消化道结构与功能的影响及与夏眠的关系。室内模拟研究结果表明7°C养殖水温下刺参的RGM最高；在7°C和14°C的养殖水温下，RGM没有显著变化。刺参在21°C下的第40天和28°C下的前20天进入夏眠前期，在28°C下的第30-40天进入夏眠期；在夏眠前期和夏眠期，刺参的RGM以及淀粉酶、脂肪酶和胰蛋白酶活性下降，而胃蛋白酶活性显著升高；分析表明高温和积温是引发刺参夏眠不可或缺的外界因素。

胶州湾悬浮颗粒物中脂肪酸的时空分布及其在初级生产者到初级消费者食物传递中的作用

研究初级食物供给与初级消费之间数量与质量的关系在海洋浮游生态系统食物网研究中占有基础地位。悬浮颗粒物及浮游动物中脂肪酸的组成和含量可以很好地为食物关系研究提供信息。当悬浮颗粒物在时空上存在数量和质量差异时，这种差异就可能在浮游动物中体现出来，而且通过脂肪酸的信息可以追踪到这种差异。本研究旨在阐明脂肪酸在悬浮颗粒物组成中的生物标记作用和在悬浮颗粒物到浮游动物食物传递过程中的营养指示作用，同时应用这一标记物研究胶州湾海域悬浮颗粒物的大体分布及其与浮游动物间的食物关系。 文章首先依据2005年3月－2006年2月胶州湾颗粒有机碳及叶绿素a的数据估测碳生物量的转化系数，发现该系数受时空环境差异的影响，平均为56，从而推导出胶州湾浮游植物有机碳浓度，进而探讨浮游植物对颗粒有机碳的贡献。对各参数分析结果显示胶州湾颗粒有机碳、叶绿素a和浮游植物有机碳年平均浓度分别为为0.47 mg.L-1、4.16 μg.L-1及0.23 mg.L-1，三者表现出相似的时空变化动态，即湾内沿岸水域较高，湾外较低，夏季较高秋冬季较低。浮游植物对颗粒有机碳的贡献较高，年平均接近37%。 对悬浮颗粒物的脂肪酸组成分析后发现饱和脂肪酸（SSFA）16:0，14:0，18:0及单不饱和脂肪酸（MUFA）Σ16:1(ω7+ω5+ω9)所占比例较高，多不饱和脂肪酸（PUFA）中EPA和DHA也相对较高。总脂肪酸在水体中的绝对浓度及在颗粒有机碳中的相对含量均存在着时空变异，二者的平均变动范围分别在4.7－60.2 μg . L-1及20.1－86.7 μg . mg-1之间，夏季高于秋冬季，空间分布上二者均在湾东部相对较高，而在湾外较低。不同脂肪酸组合的时空变化可以反映出悬浮颗粒物组成的时空动态，其中16:1ω7/18:1ω9、Σ16:1/18:1ω9、Σ16:1/Σ18:1、Σ16/Σ18、Σ16/ΣFA及20:5ω3/22:6ω3等脂肪酸组合在研究海域可以较好的指示硅藻组成，而Σ18/ΣFA 及22:6ω3/ΣFA可以指示甲藻组成，BSFA/ΣFA、Σ(Br+St)/ΣFA 、Br/St (15:0)及 Br/St (15:0+17:0)可以较好的指示细菌，SSFA/ΣFA及(24:0+26:0)/ΣFA可以示踪碎屑组分及其中的陆源成份。ω3系列脂肪酸在有机碳中的含量及在总脂肪酸中的比例以及不饱和指数可以表征悬浮颗粒物的食物质量。通过标志脂肪酸对悬浮颗粒物组成的指示发现冬季2月悬浮颗粒物组成中硅藻所占比例较高，多数月份湾内近岸水域尤其是湾东部细菌组成相对较高，而湾口至湾外水域碎屑含量相对较高。 浮游动物总平均干重生物量为72.6 mg.m-3，平面分布表现为湾内北部及中心区域生物量普遍较高，湾东部水域较低，季节变化表现为总生物量在春季4月及冬季12月形成峰值，总体上在春季5月、夏季7月及秋冬大部分月份相对较低，但不同粒径组成其动态不尽相同。浮游动物的脂肪酸组成与悬浮颗粒物存在一定差别，表现为MUFA比例下降，PUFA比例升高；SSFA中14:0的比例下降，18:0及20:0比例提高，MUFA中20:1ω9比例升高，PUFA中，EPA及DHA所占比例也相对较高。8月份总脂肪酸含量较高，9月与10月相对较小，各粒级内差别不大。 利用主成份分析发现悬浮颗粒物的组分在浮游动物中能够用相应脂肪酸指标进行示踪，当食物数量充分满足需求时，浮游动物脂肪酸特征与悬浮颗粒物组成一致性较高，同时通过脂肪酸示踪发现当潜在食物数量较丰富时，浮游动物的摄食存在选择性，这种选择可能受食物质量的调控，而当食物数量较低时，其选择性也降低。 悬浮颗粒物中EPA含量及不饱和指数是相对重要的食物质量指示物，通过对其指示特征的分析发现胶州湾总体上浮游动物的摄食会影响其食物质量组成；但在8月，浮游动物的生物量受悬浮颗粒物质量的调控，而浮游动物生物量对食物数量的摄食压力较小，认为该时期是食物质量限制对浮游动物生物量影响相对重要的时期，可以用特征脂肪酸进行清晰的分析。

Study on the fatty acid composition of jellyfish Rhopilema esculentum

The fatty acids composition in different parts of full-grown Rhopilema esculentum jellyfish from Yellow Sea was investigated. The lipids, extracted from the umbrella and oral arms and gonads of R. eculentum jellyfish, respectively were analysed by combined capillary gas chromatography/mass spectrometry. The results show that there are more than thirty kinds of fatty acids in jellyfish, and the fatty acid compositions of three parts of R. esculentum are almost the same. In the three parts, percentages of polyunsaturated fatty acids (PUFA) are high, and range from 36.23% to 38.74%. Docosahexaenoic acid (DHA), eicosatetraenoic acid (AA) and eicosapentaenoic acid (EPA) are three major PUFA.

Effects of nitrogen source and concentration on growth rate and fatty acid composition of Ellipsoidion sp (Eustigmatophyta)

In order to study the effects of different nitrogen source and concentration on the growth rate and fatty acid composition, a marine microalga Ellipsoidion sp. with a high content of eicosapentaenoic acid (EPA) was cultured in media with different nitrogen sources and concentrations. During the pre-logarithmic phase, the alga grew faster with ammonium as N source than with nitrate, but the reverse applied during the post-logarithmic phase. The alga grew poorly in N-free medium or medium with urea as the sole N source. In the same growth phase, ammonium medium resulted in higher yield of total lipid, but the EPA yield did not differ significantly different from that using nitrate medium. The maximum growth rate occurred in medium containing 1.28 mmol L-1 sodium nitrate, while maximum EPA and total lipid contents were reached at 1.92 mmol L-1, when EPA accounted for 27.9% total fatty acids. The growth rate kept stable when NH4Cl ranged from 0.64 to 2.56 mmol L-1, and the maximum content of total lipid and EPA occurred in the medium with 2.56 mmol L-1 NH4Cl. The EPA content was higher in the pre- than post-logarithmic phase, though the total lipid content was lower. The highest EPA content expressed as percent total fatty acid was 27.9% in nitrate medium and and 39.0% in ammonium medium.