海带中主要活性成分的浸提条件

以海带为原料,采用单因素实验和正交实验,研究了浸提温度、浸提时间、pH以及料液比等条件对海带中碘、甘露醇及多糖等活性成分浸出率的影响,确定了最佳浸提条件为:料液比1:30、浸提温度80℃、浸提时间9h、料液pH为2.0.在此条件下的浸提结果为碘0.347 g/100 g、甘露醇29.104 g/100 g、总糖3.502 g/100 g.     

海带硫酸酯多糖的酶法提取工艺条件

实验研究了纤维素酶提取海带硫酸酯多糖的工艺条件,通过单因素实验和正交实验,确定了最佳提取工艺条件为:粒度80~100目,固液比1∶50,提取时间4h,酶加入量60g/kg,提取率为5.641%,是热水提取工艺的1.93倍。     

条浒苔多糖的酶法辅助提取及其抗氧化活性

以多糖提取率为指标,通过单因素试验确定提取条件,采用均匀设计优化纤维素酶辅助提取,采用普鲁士蓝反应法及Fenton体系测定条浒苔多糖的还原力及对羟自由基的清除活性。试验结果表明,条浒苔多糖的提取条件为料液比1∶20,pH 9.0,温度80℃,时间6h;纤维素酶辅助提取条件为温度25℃,pH 3.0,时间6.5h,料液比1∶5,加酶量0.5%。条浒苔多糖的提取工艺为经酶处理后调整料液比至1∶20,pH及温度调整至9.0及80℃,提取6h,在此条件下多糖提取率为31.05%～37.41%。条浒苔多糖的还原力及羟自由基清除率EC50分别为32.79mg/mL和4.10mg/mL。     

虾夷扇贝内脏多糖的提取及清除羟基自由基作用的研究

通过正交试验确定最佳提取条件为:温度50℃,pH 8.0,加酶量0.25%,料液比1∶45,提取时间2.5 h;最佳条件下提取的虾夷扇贝内脏多糖具有清除羟基自由基的能力。试验结果表明,6.5 mg/m l虾夷扇贝内脏多糖对羟基自由基的清除率可达84.75%。     

海带岩藻聚糖硫酸酯电渗析分离工艺

采用电渗析法对盐沉后的海带酶解液中岩藻聚糖硫酸酯进行分离,探索工业化分离生产岩藻聚糖硫酸酯的方法,以解决目前乙醇沉淀法存在的安全性和高成本等问题。以脱盐率、糖保留率为检测指标,采用响应面法优化了电渗析工艺参数。结果显示,在操作电压80 V、料液流量3.2 L/min、固形物浓度10 mg/ml、p H=5的条件下,电渗析连续循环3次,海带酶液解干基中多糖含量由40.17%提高至47.11%,硫酸根含量由3.36%提高至4.97%。电渗析后海带酶解液干基中的金属离子含量为Ca 0.13 mg/g、Mg 16.04μg/g、Cu 0.29μg/g、Se 11.7μg/g、Cr 8.06μg/g,Pb未检出,较电渗析前均有降低。电渗析对脱除褐藻胶的海带酶解液进行脱盐纯化处理,可有效地分离纯化出岩藻聚糖硫酸酯。     

蚬精饮料的工艺技术研究

本文探讨了酶解法提取蚬多糖的影响因素和工艺条件以及蚬多糖辅以枸杞提取液研制蚬多糖饮料工艺。以加酶量、酶解时间、料液比为考察因素,L9(34)进行正交实验设计,以酶解时间90 min、加酶量1.5%、料液比1∶6、酶解温度55℃、p H7.5的最佳工艺条件得到的蚬粗多糖的提取率为312.6 mg/100 g;以感官评价为综合评价指标,通过正交法配比确定了以蚬多糖提取液(4.2 mg/m L)45 m L、枸杞提取液9 m L,香料提取液0.3%为最佳配方,具有蚬汤固有滋、气味,鲜咸适口,爽口宜人,弱腥味的蚬精饮料。     

响应面优化红毛藻多糖提取工艺及抗光氧化活性

采用纤维素酶、果胶酶辅助提取红毛藻多糖,通过单因素试验分别考察pH、酶活性、酶解温度、酶解时间等关键因素对红毛藻多糖提取率的影响,并对多糖的抗光氧化活性进行探究。以单因素试验为依据选择因素水平,以多糖提取率为指标,基于Box-Behnken中心组合试验和Design-Expert 8.0.5软件,进行三因素三水平响应面法优化红毛藻多糖提取工艺,并测定红毛藻多糖对人皮肤成纤维细胞的抗光氧化损伤作用。试验结果显示,酶辅助提取红毛藻多糖的优化工艺条件为:选用果胶酶,pH 6.0、酶活性0.22 U/mL、酶解时间100 min、酶解温度50℃。优化条件下红毛藻多糖提取率为(16.60±0.13)%,接近预测值(16.72%),此优化工艺切实可行。同时,红毛藻多糖在0～200μg/mL质量浓度范围内具有抗人皮肤成纤维细胞光氧化损伤能力,当多糖质量浓度为10～20μg/mL时,细胞活力可恢复至96.53%～98.49%。     

响应面优化沙蚕抗氧化物的超高压提取及其抗氧化活性研究

为了探讨超高压提取条件对沙蚕提取物中总酚含量的影响,采用超高压提取技术对双齿围沙蚕的抗氧化活性物质进行提取,比较不同提取条件(料液比、提取压力、提取时间及提取温度)对沙蚕提取物中总酚含量的影响,在单因素试验的基础上,采用3因素3水平的2次响应面法优化超高压提取工艺参数。结果表明,超高压提取沙蚕总酚的最佳工艺参数为:料液比1∶40(m/v,g/m L),提取压力378.72 MPa,提取时间28 min,提取温度20℃,在此提取条件下沙蚕提取物的总酚含量为8.39μg/mg干基,其清除超氧阴离子自由基、羟自由基及DPPH自由基的IC50(半数抑制浓度)分别为40.13、212.41及2.00 mg/mL。沙蚕超高压提取物具有很强的抗氧化活性。     

响应面法同步优化褶牡蛎中蛋白和多糖提取工艺

于单因素试验基础上,以牡蛎蛋白和多糖提取率(Y1和Y2)为响应值,利用响应面法对牡蛎中蛋白和多糖提取工艺进行同步优化.试验结果表明,液料比(X1)、提取时间(X2)、提取温度(X3)及pH值(X4)4个因素对Y1和Y2均有显著影响.由响应面三维及等高线叠加图得到牡蛎蛋白和多糖提取率均高的最佳提取工艺参数:液料比33∶1,提取时间2.6h,提取温度40℃,pH值4.2.在此条件下,验证试验得到牡蛎蛋白提取率为21.15％,牡蛎多糖提取率为12.07％,与数学模型预测值非常接近.可见,响应面同步优化法对牡蛎蛋白和多糖提取条件进行同步优化合理可行.     

海带抗菌活性的研究

研究了海带提取物对4种微生物:枯草芽孢杆菌、大肠杆菌、黑曲霉、酵母菌的抗菌作用,并对海带提取物的提取条件进行研究.试验结果表明:海带提取物仅对枯草芽孢杆菌具有抗菌作用;较好的提取溶剂为95%甲醇.最佳提取条件为:温度为30 ℃,时间为8 h,pH 7.     

Metabolism of fatty acids in fish. I. Development of essential fatty acid deficiency in the carp, Cyprinus carpio Linnaeus 1758

Carp, 15–25 g in weight, were maintained on diets containing linolenic acid in various concentrations (0.5, 1.0, 3.4 and 11.1 mg/g food) for 4 weeks and the fatty acid composition of liver total lipids as well as that of liver triglycerides and phospholipids was determined. The fish ingesting the diet containing 1.1% linolenate accumulated only negligible amounts of 20:3 ω 9 and exhibited a low ratio of 20:3 ω 9 to 22:6 ω 3 (0.07) in the total lipid. This ratio increased from 0.33 to 2.00 in liver total lipids of fish ingesting 3.4, 1.0 and 0.5 mg linolenic acid in 1 g of food. This effect was more pronounced in the phospholipids. The level of oleic acid in triglycerides was inversely related to the concentration of linolenic acid in the diet. Linoleic acid at a concentration of 13–16 mg/g food was unable to prevent the accumulation of 20:3 ω 9 in the lipids of fish ingesting diets containing a low level of linolenate. The possible effects of dietary linolenate on the fatty acid metabolism of fish are discussed.     

大口黑鲈“优鲈1号”选育群体肌肉营养成分和品质评价

对大口黑鲈[Micropterus salmoides(Lacépède)]"优鲈1号"(以下简称"优鲈1号")与非选育群体(简称对照组)的肌肉营养成分及营养品质进行分析比较。结果表明,"优鲈1号"和对照组肌肉中水分、粗蛋白、粗脂肪、粗灰分含量分别为73.63%和74.35%、19.34%和19.42%、4.45%和4.67%、1.09%和1.12%,统计分析表明,"优鲈1号"肌肉中水分和粗脂肪含量低于对照组,粗蛋白和粗灰分含量与对照组差异不显著(P>0.05)。对6种矿物质元素进行检测,"优鲈1号"和对照组肌肉中钙(Ca)、镁(Mg)、铁(Fe)、锌(Zn)和硒(Se)含量分别为428.34 mg/kg和424.57 mg/kg、252.63 mg/kg和259.77 mg/kg、6.92 mg/kg和5.76 mg/kg、7.73 mg/kg和5.77 mg/kg、0.40 mg/kg和0.41 mg/kg,统计分析显示"优鲈1号"肌肉中铁(Fe)和锌(Zn)含量显著高于对照组(P<0.05),其他元素差异均不显著(P>0.05)。"优鲈1号"和对照组肌肉中均测定出17种氨基酸,其总氨基酸(TAA)、必需氨基酸(EAA)和鲜味氨基酸(DAA)含量分别为18.10 mg/100 g和17.17 mg/100 g、9.46 mg/100 g和8.72 mg/100 g、8.00 mg/100 g和7.80 mg/100 g,统计分析显示差异均不显著(P>0.05)。根据氨基酸评分(AAS)和化学评分(CS)计算结果,第一限制性氨基酸均为蛋氨酸+胱氨酸(Met+Cys)。"优鲈1号"和对照组肌肉中均检测到28种脂肪酸,其中饱和脂肪酸(SFA)、单不饱和脂肪酸(MUFA)、多不饱和脂肪酸(PUFA)分别为13.96 g/kg和14.68 g/kg、13.66 g/kg和14.72 g/kg、16.37 g/kg和16.58 g/kg,其中饱和脂肪酸/不饱和脂肪酸(SFA/UFA)均为0.47。综上所述,"优鲈1号"仅在水分、粗脂肪、铁(Fe)和锌(Zn)含量上略优于对照组,其他肌肉营养成分和含量差异均不显著(P>0.05)。     

Dietary thiamin requirement of fingerling Channa punctatus (Bloch) based on growth,protein gain,liver thiamin storage,RNA/DNA ratio and biochemical composition

Dietary thiamin requirement of fingerling Channa punctatus was quantified by feeding casein/gelatin‐based diets (450 g/kg CP; 18.39 kJ/g GE) with seven graded levels of thiamin (0, 0.5, 1, 1.5, 2, 2.5 and 5 mg/kg diet) to triplicate groups of fish (6.9 ± 0.93 cm; 4.91 ± 0.62 g) for 16 weeks. Fish fed diet with 2.5 mg/kg thiamin reflected highest absolute weight gain (AWG), protein gain (PG), RNA/DNA ratio and lowest feed conversion ratio. Similarly, highest liver thiamin concentration was also recorded in fish fed 2.5 mg/kg thiamin diet. Hepatic thiobarbituric acid reactive substance (TBARS) concentration responded negatively with increasing concentrations of dietary thiamin up to 2.5 mg/kg, whereas superoxide dismutase and catalase activities were found to improve with the increasing levels of dietary thiamin from 0 to 2.5 mg/kg. Transketolase activity also improved as the thiamin concentrations increased up to 2.5 mg/kg. Broken‐line regression analysis of AWG, PG, RNA/DNA ratio, liver thiamin concentrations, transketolase and TBARS activities exhibited the thiamin requirement in the range of 2.34–2.59 mg/kg diet. Data generated during this study would be useful in formulating thiamin‐balanced feeds for the intensive culture of this fish.     

大鲵肉酶解产物的制备及其抗氧化性的研究

以大鲵肉为原料,利用Aspergillus sp.酸性蛋白酶进行酶解,研究其最佳的酶解条件以及酶解产物的抗氧化作用。结果表明,大鲵肉酶解的最佳工艺条件为Aspergillus sp.酸性蛋白酶加酶量为0.4%(质量比)及底物浓度为0.1g/mL时,酶解时间5.5h,pH 2.0,温度45℃。时间飞行质谱表明酶解产物的分子量小于2 000,苯酚硫酸法测定糖含量为2%,Folin-酚试剂法测蛋白含量为93%。大鲵酶解产物清除羟基自由基(.OH)和DPPH自由基的能力随浓度升高而增强。     

栅藻B38营养成分分析及蛋白质营养价值评价

对栅藻B38的营养成分进行了全面分析,结果表明,栅藻藻粉中油脂含量14%,总糖含量13.86%,粗纤维3.52%,灰分4.28%,蛋白质49.0%,为高蛋白质类微藻。栅藻B38中含有23种脂肪酸。栅藻B38中氨基酸总量为852.58 mg/g,必需氨基酸占总氨基酸的47.45%,必需氨基酸指数为85.42%。两种模式的氨基酸比值系数分较接近,均在65以上;待评价物质的氨基酸品质与模式蛋白的贴近度接近1(0.93和0.88)。栅藻B38中共检测出23种矿物质元素,其中钠、钾、钙、镁、铁、铝含量较为丰富。重金属的含量均低于国家食品卫生标准。栅藻B38中维生素B3(106.02 mg/100 g)和维生素E(540.77 mg/100 g)的量较高。综上,栅藻B38的营养较丰富,可以进一步开发利用。     

养殖博氏鱼芒肉营养成分的分析及评价

采用国家标准方法测定湖北英山博氏(鱼芒)肉一般营养成分、氨基酸、脂肪酸和矿物质元素含量.结果表明,博氏(鱼芒)肉中水分、粗蛋白、粗脂肪和粗灰分的含量分别为75.36％±1.07％、17.90％±0.43％、5.13％±0.18％和0.98％±0.09％;18种氨基酸总量为(69.01±0.07) g/100 g(干重),其中5种鲜味氨基酸占氨基酸总量的41.70％,8种人体必需氨基酸占氨基酸总量的48.68％,必需氨基酸与非必需氨基酸比值为95.06％;粗脂肪中含24种脂肪酸,油酸含量38.41％±0.29％最高,单不饱和脂肪酸含量占脂肪酸总量的42.68％±0.10％,n-6多不饱和脂肪酸与n-3多不饱和脂肪酸的比值为1.48;矿物质元素中钾含量最高,为(1 118.51±30.67) mg/100 g(干重),微量元素中,铁、锌含量最高,分别为(1.19±0.10)和(1.18±0.05)mg/100 g(干重).与其它鱼类相比,博氏(鱼芒)肉蛋白质质量较高,氨基酸组成比例均衡,富含n-3多不饱和脂肪酸,矿物质元素含量丰富,有较高的营养价值.     

Comparison of Docosahexaenoic Acid (22:6n-3) Levels in Various Artemis Strains during Enrichment and Subsequent Starvation

Abstract.— The aim of this study was to compare the levels of docosahexaenoic acid (DHA, 22:6n-3) in three different bisexual and one parthenogenetic strains of Artemia after enrichment. Freshly-hatched nauplii from A. franciscana (Great Salt Lake, USA), A. sinica (Yimeng, P. R. China), A. persimilis (Argentina), and A. parthenogenetica (Tanggu, P. R. China) were enriched with a purified lipid emulsion containing 95% DHA ethyl esters (% total fatty acids) and subsequently starved. All strains had very low initial DHA levels (< 0.3 mg/g dry weight). Initial eicosapentaenoic acid, 20:5n-3 (EPA) levels were high in A. parthenogenetica (18.2 mg/g dry weight) as compared to those in the other strains (4.6-8.5 mg/g dry weight). After 24-h enrichment, A. sinica contained the highest DHA level (37.0 mg/g dry weight) as well as the highest DHA/ EPA ratio (3.7). The lowest DHA enrichment levels were found in A. franciscana and A. parthenogenetica (26.3 and 22.7 mg/g dry weight, respectively). During the subsequent 24-h starvation period, the contents of DHA decreased rapidly in all strains, whereas EPA levels remained relatively stable. This indicates the high catabolism of DHA for energy production, the relative conservation of EPA, and possibly a partial bioconversion of DHA to EPA during the starvation period in each species.     

恶喹酸与诺氟沙星对异育银鲫体内嗜水气单胞菌的抑菌效果比较

在水温(25±2)℃下,给体质量150~200g的异育银鲫分别口灌3种剂量(20、30、40mg/kg)的诺氟沙星和恶喹酸,结合这两种药物对嗜水气单胞菌AH10的体外药效学研究和对异育银鲫单次口灌不同剂量的诺氟沙星、恶喹酸的体内药代动力学,研究诺氟沙星、恶喹酸对异育银鲫体内嗜水气单胞菌AH10的抑菌效果。试验结果表明,恶喹酸和诺氟沙星对嗜水气单胞菌AH10的最小抑菌质量浓度分别为1μg/mL和0.5μg/mL。口灌上述3种剂量恶喹酸、诺氟沙星后,异育银鲫血浆中恶喹酸的最大药物质量浓度分别为4.1μg/mL、6.0μg/mL和8.89μg/mL;诺氟沙星的最大药物质量浓度分别为11.5μg/mL、15.1μg/mL和18.9μg/mL;恶喹酸的最大药物质量浓度/最小抑菌质量浓度分别为4.1、6.0和8.89;诺氟沙星的最大药物质量浓度/最小抑菌质量浓度分别为23、30.2和37.8;恶喹酸0~24h内药—时曲线下面积/最小抑菌质量浓度分别为21.6214、33.1449、39.1846;诺氟沙星0~24h内药—时曲线下面积/最小抑菌质量浓度分别为274.75、451.55、578.35。综合0~24h内药—时曲线下面积/最小抑菌质量浓度、最大药物质量浓度/最小抑菌质量浓度这两个指标可知,诺氟沙星对异育银鲫体内的嗜水气单胞菌AH10抑制效果强于恶喹酸。     

Dietary pantothenic acid requirement of fingerling Channa punctatus (Bloch) based on growth,feed conversion,liver pantothenic acid concentration and carcass composition

A 16‐week feeding trial was conducted to determine the dietary pantothenic acid requirement of fingerling Channa punctatus. Six casein–gelatin‐based diets (450 g/kg CP; 18.39 kJ/g GE) with graded levels of pantothenic acid (0, 10, 20, 30, 40 and 50 mg/kg diet) were fed to triplicate groups of fish (6.2 ± 0.71 cm; 4.26 ± 0.37 g) near to apparent satiation. The growth evaluation in terms of absolute weight gain (AWG), feed conversion ratio (FCR) and protein retention efficiency (PRE) indicated the best performance (p < .05) in fish fed diet containing 30 mg/kg pantothenic acid. Highest haemoglobin, haematocrit and RBCs counts were also obtained in fish fed diet with 30 mg/kg pantothenic acid. Mean cell haemoglobin and mean cell volume were found to be lowest in fish fed pantothenic acid‐free diet indicating the anaemia in this group of fish. Superoxidase dismutase and catalase activities of liver tissue were found to improve (p < .05) with the increasing levels of dietary pantothenic acid from 0 to 30 mg/kg. However, liver pantothenic acid concentration responded positively with the increasing levels of pantothenic acid up to 40 mg/kg diet and then stagnation in liver pantothenic acid concentration with the further inclusion of pantothenic acid was recorded. Second‐degree polynomial regression analysis of AWG, FCR and PRE exhibited the pantothenic acid requirement at 36.4, 32.8 and 34.7 mg/kg diet, respectively. Data generated during this study would be useful in formulating pantothenic acid‐balanced commercial feeds for the intensive culture of this fish.     

Pharmacokinetics and bioavailability of flumequine and oxolinic acid after various routes of administration to Atlantic salmon in seawater

The present preclinical study was performed to investigate the pharmacokinetics of flumequine in Atlantic salmon (Salmo salar L.) in seawater after administration of different doses and dosage formulations. Flumequine was administered intravenously (dose 4.9 mg/kg fish) and orally from the drug delivery system Aqualets as Apoquin 5 g/kg (dose 25 mg/kg) and 10 g/kg (dose 50 mg/kg), respectively. Experiments were carried out with oxolinic acid administered in the same way for the purpose of comparing the two compounds. The seawater temperature was 5±0.2°C in all experiments.

The pharmacokinetic calculations showed that the distribution half-life for flumequine was and for oxolinic acid . The drugs were absorbed rapidly, and flumequine reached a plasma concentration of C_max = 2.26 μg/ml after a single oral dose of 25 mg/kg, whereas oxolinic acid reached C_max = 0.99 μg/ml. The apparent bioavailability of flumequine was found to be 40–45%, whereas the apparent bioavailability of oxolinic acid varied from 25% at a dose of 50 mg to 40% at a dose of 25 mg/kg body weight of fish. The distribution profile of flumequine in the various compartment of fish appeared to be different from that of oxolinic acid. After a single oral dose (25 mg/kg) the areas under the concentration-time curves showed that flumequine was 2.3 times more concentrated in plasma and 2.6 times more concentrated in liver compared to oxolinic acid. In muscle the difference was less pronounced, flumequine being 1.4 times more concentrated than oxolinic acid.