反相高效液相色谱法测定褐藻中岩藻黄素的含量

建立一种反相高效液相色谱法用于海藻中岩藻黄素的定量分析,并测定新鲜及干制褐藻中岩藻黄素含量,探究不同干制方式对褐藻岩藻黄素的影响。样品经甲醇提取、C18柱固相萃取净化后,采用ZORBAX SB-C18色谱柱,流动相采用水与甲醇梯度洗脱,流速0.7 ml/min、进样量10μl、柱温35℃、检测波长450 nm进行液相色谱分析。在该条件下,岩藻黄素在0.11~50 mg/L范围内有良好的线性关系(Y=38.46X+0.8899,R~2=0.9999),检测限为0.03 mg/L,回收率为92.66%~109.06%,相对标准偏差(RSD)为3.46~4.61%。采用该方法,岩藻黄素提取净化完全,杂质干扰小,回收率高,能够对海藻及其制品中岩藻黄素进行准确定量。采用该方法测得新鲜海带和马尾藻的岩藻黄素含量(干基)分别为559.2和680.4 mg/kg,而干制褐藻样品中岩藻黄素的含量明显低于新鲜褐藻。不同干制方式造成的岩藻黄素损失程度为真空冷冻干燥45℃烘干≈自然晾干。因此,在规模化分离制备海藻岩藻黄素时,宜采用新鲜或冻干海藻作为原料,从而保证岩藻黄素的得率。     

不同处理方式对海带类胡萝卜素含量的影响

采用有机溶剂提取法从海带中提取类胡萝卜素,通过类胡萝卜素含量的测定与薄层色谱分析,研究不同干燥方式及皂化处理方式对海带类胡萝卜素的影响.结果表明,无论何种干燥方式均会破坏海带类胡萝卜素.相比之下,冷冻干燥方式优于其他干燥方式；高温短时干燥优于低温长时干燥；而经阳光曝晒的海带中类胡萝卜素含量最低.皂化处理会破坏海带类胡萝卜素中的岩藻黄素,故皂化处理不适合用于含有岩藻黄素的样品.     

甲壳素对海带生长和生理活性的调控

在海带夹苗放养时,分别用150,200,250mg kg甲壳素浸苗2h,可提高叶绿素和岩藻黄素含量,促进光合作用,增强海带对N、P、K的吸收,增加蛋白质和核酸含量,从而促进海带迅速生长,为产量的形成打下早期生长的基础。     

三十烷醇对铜藻生长及岩藻黄素含量的影响

为探讨三十烷醇对铜藻生长的影响，本研究采用不同浓度(0、0.1、 0.5、1.0 和2.0 mg/L)的三十烷醇连续施用20 d，或用三十烷醇浸泡处理24 h后，再恢复正常条件培养20 d，分别测定了铜藻的生长、生理生化指标(光合色素、可溶性蛋白、可溶性糖)以及岩藻黄素含量的变化情况。结果显示，连续施用5 d时，各组藻体的比生长速率(RGR)、叶绿素a(Chl.a)、类胡罗卜素(Car)、可溶性蛋白、可溶性糖的含量均显著高于对照组；15 d时，2.0 mg/L浓度组的铜藻生长受到抑制，各项生理指标均显著下降；20 d时，除了0.1 mg/L浓度组的铜藻生长仍有促进外，其他3个较高浓度的施用组均受到不同程度的抑制，且三十烷醇的浓度越高，抑制作用越明显。经三十烷醇浸泡处理的藻体恢复正常条件培养5 d时，各组藻体的RGR、Chl-a、Car、可溶性蛋白和可溶性糖的含量均显著上升；10 d时，0.5和1.0 mg/L浓度组的铜藻生长速率仍显著高于对照组，但15 d时已与对照组无显著差异，且综合各项生理生化指标，1.0 mg/L组的促进作用最为明显，这种促生长的作用能持续到处理后10 d左右。岩藻黄素的含量除连续施用2.0 mg/L组在实验20 d时低于对照组外，其余各实验组在培养20 d内均显著高于对照组，其中1.0 mg/L三十烷醇浸泡处理24 h恢复培养10 d，可使岩藻黄素的含量提高79.5%。研究表明，连续施用低浓度的三十烷醇(0.1 mg/L) 20 d或以1.0 mg/L三十烷醇每10 d浸泡处理24 h，对铜藻的生长和岩藻黄素的积累有显著的促进作用。     

内蒙古碱湖一株菱形藻的分离鉴定及其应用潜力评价

从内蒙古哈马太湖中分离得到一株淡水硅藻NW129,经形态学和分子生物学鉴定,该藻株与菱形藻属的普通菱形藻亲缘关系最近。该藻在温度28℃、光照100μmol/(m~2·s)、光暗周期12 h∶12 h,摇床转速为160 rpm的条件下培养。在Zarrouk培养基中,连续培养25 d。培养12 d,干重达到1.06 g/L,每天平均生长率为0.10 g/(L·d),培养至25 d,干重达到1.95 g/L,后13 d的平均生长率仅为0.08 g/(L·d)。整个生长过程中,培养液pH从初始的9.20增至12.30。培养25 d后,采收藻细胞总脂含量为24.00%,可溶性蛋白为12.00%,多糖比例为3.35%,岩藻黄素含量达13.06 mg/g。结果表明,该藻株速生性状突出,对高pH耐受能力强,岩藻黄素含量高,是一株具有开发应用潜力的藻株。     

三十烷醇对海带生长和生理活性的影响

在海带夹苗放养前,用0.5～1.0ppm三十烷醇浸苗,能提高叶绿素和岩藻黄素含量,促进光合作用,并可在相当长时间内,提高海带对磷酸盐和硝酸离子的吸收,还可使海带体内核酸含量增加,进而促进海带迅速生长,缩短了放养后的缓苗时间,为产量的形成打下早期生长的基础。     

离子色谱法和氯化钡一明胶法测定海带岩藻聚糖硫酸酯中硫酸根含量的比较

岩藻聚糖硫酸酯（Fucoidan）是一种以岩藻糖为主要成分的含有硫酸酯的水溶性杂聚糖。研究发现，岩藻聚糖硫酸酯在医学方面具有独特的抗凝血、抗肿瘤、抗HIV、抗血栓、提高免疫力、降血脂等活性，而硫酸根含量对其生理活性的影响最大。目前从对泡叶藻、墨角藻、昆布、钩鹿角藻等制备的岩藻聚糖硫酸酯的抗凝和抗血栓活性及构效关系的报道中发现，     

岩藻聚糖硫酸酯抗炎、抗氧化及其交互作用研究进展

<正>岩藻聚糖硫酸酯是一种主要存在于褐藻和海洋无脊椎动物中的天然活性成分。岩藻聚糖硫酸酯结构中含有L-岩藻糖和硫酸基团,是一种具有多种生物活性的酸性杂多糖,已有研究表明,其具有抗氧化、减轻炎症反应、抑制肿瘤细胞生长、预防心脑血管疾病和肾功能衰竭等生物活性^[1]。因其源于天然原料,来源丰富,并且安全无毒副作用,近年来人们对岩藻聚糖硫酸酯的活性研究越来越关注。     

海带岩藻聚糖硫酸酯纯化去除重金属砷和铅的研究

从福建省沿海生长的海带中提取岩藻聚糖硫酸酯,采用截留分子量50、30、10ku的平板超滤膜进行梯度超滤,发现50ku以上占了提取的岩藻聚糖硫酸酯的(84.29±2.772)%。采用EDTA和盐酸处理分子量大于50ku的岩藻聚糖硫酸酯,结合超滤技术进行脱除重金属As和Pb元素的研究,分别用原子荧光光谱仪和电感耦合等离子质谱检测处理前后岩藻聚糖硫酸酯中重金属As和Pb元素的残留量。结果显示,超滤后岩藻聚糖硫酸酯的相对电导率明显降低;用SPSS13.0统计方法对数据进行t检验,结果表明,试验组与对照组存在显著性差异,即用超滤结合螯合方法能显著脱除岩藻聚糖硫酸酯中重金属As和Pb。     

刺参岩藻聚糖含量的研究

以木瓜蛋白酶水解比色法测定刺参中岩藻聚糖的含量。水解液经次甲基蓝染色,在560nm处有最大吸收波长。吸光度与刺参中岩藻聚糖含量成正比。测定的刺参酸性粘多糖回归方程:y=-0.0189 0.0345x;r=0.9991。并研究了6种不同产地的刺参中岩藻聚糖的含量。     

Promising antidiabetic potential of fucoxanthin isolated from the edible brown algae Eisenia bicyclis and Undaria pinnatifida

In the present study, we investigated the antidiabetic potential of fucoxanthin via the inhibition of rat lens aldose reductase (RLAR), human recombinant aldose reductase (HRAR), advanced glycation end-product (AGE) formation, protein tyrosine phosphatase 1B (PTP1B), and α-glucosidase. Fucoxanthin displayed potent inhibitory activity against AGE formation and HRAR and RLAR activity. In addition, fucoxanthin showed potent inhibitory activity against PTP1B. However, it did not show α-glucosidase inhibitory activity below 200 μM. In addition, our kinetic study revealed that fucoxanthin competitively inhibited RLAR, while it showed mixed-type inhibition against PTP1B. In order to confirm enzyme inhibition, we predicted the 3D structure of PTP1B using Autodock 4.0 to simulate the binding of fucoxanthin. Docking simulation results demonstrated that three residues of PTP1B (Phe30, Phe52, and Gly183) interact with the two hydroxyl groups of fucoxanthin. In addition, the binding energy was negative (?7.66 kcal/mol), indicating that the three hydrogen bonds may stabilize the open form of the enzyme and potentiate tighter binding to the active site of PTP1B, resulting in more effective PTP1B inhibition. The results of the present study therefore clearly demonstrate the promising potential of fucoxanthin as a therapeutic intervention for the management of diabetes as well as diabetes-associated complications, which could be explored further.     

In vitro monoamine oxidase A and B inhibitory activity and molecular docking simulations of fucoxanthin

Fucoxanthin is the primary carotenoid found in edible seaweeds, such as Eisenia bicyclis, Undaria pinnatifida, and others. The aim of this study was to determine the effectiveness of fucoxanthin against Parkinson’s disease (PD) by inhibiting monoamine oxidase (MAO) A and B because MAO inhibitors are used in early management of PD. A sensitive enzyme-based chemiluminescent assay and kinetics methods were used to investigate the enzyme inhibitory activities and mode of inhibition. A molecular docking simulation was performed to clarify the binding characteristics of fucoxanthin to hMAO-A (2z5x) and hMAO-B (2v5z). Our results suggest that fucoxanthin shows significant inhibitory activity against hMAO-A and hMAO-B with IC₅₀ values of 197.41 ± 2.20 and 211.12 ± 1.17 μM, respectively. Selegiline was used as the positive control (IC₅₀: 10.54 ± 1.25 and 0.128 ± 0.01 μM for hMAO-A and hMAO-B, respectively). The enzyme-based kinetics results demonstrated that fucoxanthin inhibited both hMAOs in a reversible competitive manner. The molecular docking simulation predicted that fucoxanthin exhibits higher binding affinity towards hMAO-A and hMAO-B through hydrogen bonding and hydrophobic interactions. These findings suggest that fucoxanthin is a reversible competitive hMAO inhibitor that could be used to manage PD.     

Application of Two-Level Full Factorial Design for the Extraction of Fucoxanthin and Antioxidant Activities from Sargassum siliquosum and Sargassum polycystum

Two-level full factorial design was employed to identify the extraction parameters that can improve the derivation of fucoxanthin content (FC), total carotenoid content (TCC), and antioxidant from two brown seaweeds, Sargassum siliquosum (SS) and Sargassum polycystum (SP). These parameters included temperature (A: 4–45°C), time (B: 30–1,440 min), and solvent-to-solid ratio (C: 10–50 ml/g). Antioxidant activities were determined as trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, and ferric-reducing antioxidant power (FRAP). Results showed that all three factors were significant (p < 0.05) in providing higher FC in both species. These factors were also significant in obtaining higher TCC in SS; whereas in SP, TCC was only affected by solvent-to-solid ratio. Only temperature was found to contribute significantly to a higher TEAC in both species. However, none of the factors improved DPPH for SS, except temperature and time for SP. For SS, only time was significant in obtaining higher FRAP; whereas temperature and time were significant for SP. Hence, results indicate that a simple modification in the extraction temperature, time, and solvent-to-solid ratio will be able to improve the derivation of fucoxanthin, carotenoids, and antioxidant activities.     

Phytoplankton dynamics in shrimp ponds

The productivity, community composition and dynamics of phytoplankton were examined in commercial shrimp [= penaeid prawn] ponds in eastern Australia. Nutrient and light regimes were examined concurrently. Analysis of chlorophyll a, algal accessory pigments and bacterial numbers over a 6-month period showed considerable daily variation. Bacterial numbers and nutrient concentrations were not significantly different between the top and bottom of the water column nor between sites within a pond, but there were significant depth differences in chlorophyll a, and the diatom and cyanobacteria indicator pigments, fucoxanthin and zeaxanthin, and site differences in alkalinity and fucoxanthin. Statistical analysis of spatial and temporal variation was used to develop sampling strategies. Our results showed that to accurately reflect changes in phytoplankton throughout the grow-out season, chlorophyll a and the accessory pigments must be sampled for longer than five consecutive days. A suggested alternative to manual sampling is the use of automated loggers. Factors that might be limiting phytoplankton growth and affecting community composition were determined. Light appears to be limiting phytoplankton growth and it is suggested that a shallower pond depth and/or higher turbidity would increase algal productivity. Changes in nitrogen-to-phosphorus ratios and ammonia concentrations coincided with changes in phytoplankton community structure.     

鱼类白介素10的研究进展

白介素10(Interleukin 10, IL-10)是能够参与机体免疫的一种多功能细胞因子,由单核细胞、巨噬细胞等多种免疫细胞分泌,在抗肿瘤、抗感染、免疫性疾病等多种疾病的发生发展过程中发挥重要作用。有多种硬骨鱼IL-10被克隆表达,也被证实具有免疫调节作用,目前也有不少关于鱼类IL-10的生物活性、作用机制、调节机制的研究。本文根据已有报道,从鱼类IL-10的基因结构、转录表达、来源与进化、生物学活性及功能、鱼类IL-10受体及信号通路等五个方面进行了综述,为鱼类IL-10的研究与应用提供依据。     

Analysis of Phytosterol,Fatty Acid,and Carotenoid Composition of 19 Microalgae and 6 Bivalve Species

ABSTRACT

In this study, the functional components of 19 microalgae and 6 bivalve species were investigated in the context of the application in bivalve feeding and human health food. Principal component analysis was performed to detect any association between the functional components and individual microalgal species or taxonomic group. The proportions of the functional components differed depending on the taxonomic group or species of microalga. The genera Cheatoceros, Thalassiosira, and Isochrysis contained high concentrations of fucosterol and fucoxanthin, which are present in large amounts in brown algae. Diatoms, haptophytes, and eustigmatophytes, which are used as feed for bivalves, were rich in fucosterol and eicosapentenoic acid (EPA); further, haptophytes were rich in docosahexaenoic acid (DHA). In addition, the microalgae associated with red tide, i.e., the raphidophytes, were found to be rich in fucoxanthin, β-sitosterol, and EPA, whereas dinoflagellates were rich in DHA. Seven bivalve species also contained high concentrations of fucosterol, EPA, and DHA, as did microalgae, which were used to feed by bivalves. These results are useful in selecting microalgae effectively as feed of the bivalves.     

基于围隔实验研究虾夷扇贝与龙须菜养殖对浮游植物群落结构的影响

2015年秋季在桑沟湾开展围隔实验,研究了60 h内高容量虾夷扇贝(Patinopecten yessoensis)和龙须菜(Gracilaria lemaneiformis)养殖对水体中物理、化学和生物(浮游植物群落)等因素的影响。结果显示,养殖的虾夷扇贝和龙须菜在60 h内能显著改变水体中的溶解氧(DO)和溶解态无机氮(DIN)的浓度,同时,能显著影响浮游植物种群丰度和组成特征。从各实验组来看,12 h后,虾夷扇贝和龙须菜实验组浮游植物丰度显著低于空白实验组。虾夷扇贝对水体中4种硅藻优势种[包括柔弱拟菱形藻(Pseudo-nitzschia delicatissima)、双菱藻(Surirella sp.)、菱形藻(Nitzschia spp.)、针杆藻(Synedra spp.)]的滤除效应存在较大差异,即对柔弱拟菱形藻和双菱藻有较大的滤除效应,但对菱形藻和针杆藻却影响不大。基于水体中的光合色素变化特征也揭示了虾夷扇贝对浮游植物的选择性摄食效应,即虾夷扇贝能显著滤除水体中的岩藻黄素(fucoxanthin,硅藻特征色素)、别藻黄素(alloxanthin,隐藻特征色素)。与此相反,青绿藻素(prasinoxanthin,微微型藻类的特征色素)在48 h后,虾夷扇贝实验组显著高于空白实验组和大型藻实验组,说明龙须菜养殖对微微型青绿藻生物量无显著影响。     

卟啉铁在猪饲料中的应用

由于具有较高的生物活性,卟啉铁在动物机体内的吸收率比一般补铁剂高很多,作为一种优质高效铁源,卟啉铁已逐步被发展成为一种新型绿色饲料添加剂。在养猪生产中,卟啉铁可作为高效铁源补充猪对铁的需求,并能有效改善猪的生长性能和外观。随着有毒副作用的促生长剂慢慢退出猪饲料添加剂行列,卟啉铁在畜牧养殖中必将发挥出重要的作用。