Calcium pretreatment increases thermotolerance of Laminaria japonica sporophytes —Using Yaluhe farm as an example

Calcium is a secondary messenger in plant signaling, and its concentration changes spatially and temporally during the course of heat stress. In the present study, potassium antimonate was used to visualize calcium localization in blades of a marine macroalga, the juvenile Laminaria japonica sporophytes under heat stress (25℃). Result showed that loosely bound calcium was mainly distributed on the cell wall under normal conditions (10℃), and flowed into the cytoplasm when exposed to heat. The simutaneous assay on the antioxidant system changes was performed. Oxidative damage, as measured by generation of reactive oxygen species (ROS) malondialdehyde (MDA) content, increased significantly during heat stress, and calcium pretreatment alleviated oxidative damage. The assay on the activities of six antioxidant enzymes demonstrated that their enzymatic activities were inhibited when exposed to heat stress, but Ca2+ pretreatment effectively attenuated the inhibition. Results in the present study inferred that calcium homeostasis plays an essential role in L. japonica sporophyte when exposed to heat, and calcium pretreatment could improve its thermo-tolerance.     

植物激素对海带孢子体发生的影响

采用析因试验设计,对影响海带孢子体发生的主要环境因子进行优化,筛选出温度8℃、光强30umol-m^-2·s^-1、光时12h的最佳环境条件．基于此条件,对吲哚乙酸（IAA）、赤霉素（GA,）、脱落酸（ABA）、激动素（KT）和矮壮素（CCC）等5种植物激素进行了初步筛选,结果表明0．1mg·L^-1IAA、2．0mg·L^-1KT对海带孢子体的发生有显著促进作用,0．5mg·L“IAA及0．1、0．5、1．0mg·L^-1ABA抑制孢子体的发生,GA3、CCC无显著的影响．采用拉丁方区组设计,对具有显著促进作用的KT进行浓度筛选,获得了促进孢子体发生的最佳浓度4mg·L^-1．在此条件下,孢子体于第5天发生,第16天发生率达94．2％±2．0％,孢子体发生显著加快．此外,孢子体发生与细胞增殖呈异速生长关系,并且连续光照斜率高于短光照,表明短光照更适合孢子体的发生．     

海带凝集素的分离及性质研究

海带 (Laminariajaponica)经TBS缓冲液粗抽提 ,然后进行硫酸铵分级实验 ,测定盐析范围为 70 %硫酸铵饱和度 ,经 70 %硫酸铵饱和度分级后 ,海带凝集素 (LJL)纯化倍数为 9,总活力回收为 410 % ,LJL粗抽提液糖含量为12 .94% .该凝集素不被已测试的D 果糖、葡萄糖、γ 球蛋白所抑制 ,但被卵清蛋白抑制     

海带热休克蛋白70基因体外原核表达研究

在前期研究克隆得到全长海带HSP70基因的基础上,为进一步研究藻类HSP70的生物学功能,将海带HSP70基因的开放阅读框区域克隆到表达载体pEASY-E2中,并转化到大肠杆菌BL21（DE3）pLysS。将阳性重组子培养于含有AMP（100 U/mL）的LB培养基,IPTG诱导表达,SDS-PAGE电泳鉴定。经5 h诱导,其表达量达到平台期,继续培养HSP70表达量并不显著增高。5 mM IPTG诱导海带HSP70蛋白表达量高于1 mM IPTG诱导蛋白表达量。     

海带抗氧化多酚的制备及活性研究

用1:1的氯仿:甲醇超声提取海带成分,并用石油醚、乙酸乙酯和正丁醇依次进行萃取,利用DPPH法、邻二氮菲-Fe2+氧化法、铁氰化钾还原法和邻苯三酚自氧化进行抗氧化实验,同时与抗氧化剂2,6-二叔丁基对甲酚(BHT)和没食子酸(GA)进行对照。结果显示海带提取物与各萃取组分均具有较强的抗氧化能力,其中乙酸乙酯提取物(EA)抗氧化活性最强。在50μg/mL浓度时,EA清除DPPH自由基、羟自由基、超氧阴离子自由基的能力和还原能力均高于抗氧化剂BHT,且清除超氧阴离子自由基的能力也高于GA;另外,Aqueous组分在所有测定浓度下清除羟自由基能力均高于GA,清除O2-的能力也高于BHT。海带各提取物总酚含量的分析表明总酚含量与抗氧化活性之间具有一定的相关性,总酚含量高其抗氧化能力也相应提高,表明多酚是提取物中重要的抗氧化成分。4种抗氧化方法的比较表明DPPH法的相关系数最高(R=0.987),是海带体外抗氧化实验最有效的方法。     

海带对罗源湾养殖区海水的生物修复研究

研究了罗源湾海带栽培期间3-5月的水质状况,以及室内海带个体对养殖废水的净化作用.结果表明:大面积海带栽培可改善罗源湾的水质状况,降低无机氮磷含量.3-5月海带栽培区的总无机氮(DIN)的降低率分别达到25.48％、19.62％、44.65％,总无机磷(DIP)的降低率分别为20.17％、32.00％、38.72％.在7d实验期间,海带个体对养殖废水的净化效果明显,DIN的去除率可达98％以上.海带在养殖废水中能正常生长,保持一定的日增长率,鲜质量及叶片长有所增加.     

海带中脱落酸的分离纯化及高效液相色谱分析

探索了海带（Laminaria japonica）脱落酸的分离纯化条件,获得最适分离纯化方法为：常温组织匀浆,80%甲醇溶液浸提,乙酸乙酯萃取,硅胶脱色和纯化.在此基础上,利用反向高效液相色谱的方法对样品进行定性定量分析,结果表明样品中含有脱落酸,含量为30.5-60.5μg/kg.这为海藻脱落酸的分离纯化及其活性研究奠定了基础.     

海带多糖对四氯化碳致小鼠肝损伤的保护作用

目的：主要研究海带多糖对四氯化碳致小鼠急性肝损伤的保护作用．方法：小鼠随机分为6组,给药4d后,腹腔注射0．3％四氯化碳（CCl4）,16h后取血、肝组织匀浆测定．结果：不同剂量的海带多糖均能阻止血清中丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、乳酸脱氢酶（LDH）的升高;能增加血清中一氧化氮（NO）含量、一氧化氮合酶（NOS）活力;增加组织中超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-PX）活力．结论：海带多糖对四氯化碳致小鼠急性肝损伤有保护作用．其机理可能是海带多糖能清除氧自由基,提高机体的抗氧化能力．     

The study of antioxidant activities of fucoidan from Laminaria japonica

Two large molecular weight fucoidan fractions F-A and F-B were obtained by water extraction and anion-exchange chromatography and then L-A and L-B with low molecular weight and uronic acid content were prepared by radical process degradation of F-A and F-B. The antioxidant activities of the fucoidan fractions on two oxygen free radicals and Cu2 -induced low-density lipoprotein (LDL) oxidation were studied. The results show that all the fucoidan fractions had excellent scavenging capacities on superoxide radical and hypochlorous acid, except the highly sulfated fraction L-B. In LDL oxidation system, low molecular weight fractions L-A and L-B exhibited great inhibitory effects on LDL oxidation induced by Cu2 , however F-A and F-B had little inhibitory effects in this system due to their large molecular weights. The present results suggest that fucoidan from Laminaria japonica is an excellent natural antioxidant and has great potential for preventing the free radical-mediated diseases.     

海带对密执安棒形杆菌环腐亚种的抑菌活性及其加工制剂的研究

报道了海带乙醇提取物对密执安棒形杆菌环腐亚种的抑菌作用。海带乙醇提取物对密执安棒形杆菌环腐亚种的最低抑菌浓度为0.38 mg/mL,最低杀菌浓度为0.75 mg/mL。稳定性实验结果表明:海带乙醇提取物在pH为5时,可达到最好的抑菌效果。提取物在紫外光下的抑菌活性稳定。Mn2+、Ba2+、Zn2+、Fe3+可增强提取物的抑菌活性,Ca2+可降低提取物的抑菌活性。海带乳油的配方为:提取物(20%)、乙醇(10%)、吐温-80(4%)及水(66%)。海带乳油具有良好的稳定性及分散性,可以作为化学杀菌剂的代替品开发利用。     

Expression of hepatitis B surface antigen gene (HBsAg) in Laminaria japonica (Laminariales, Phaeophyta)

A transformation model for Laminaria japonica was established from 1993 to 1998, on the basis of which the transgenic kelp with heterologous gene encoding hepatitis B surface antigen (HBsAg) was obtained by using the micro- particle bombardment transformation method. Results of quantitative ELISA showed that HBsAg in transgenic kelp was 0.529 μg/mg soluble proteins on average and the highest value was 2.497 μg/mg, implying that recombinant HBsAg had natural epitope. Further support for the integration of HBsAg gene into kelp genome was obtained by PCR- Southern and total DNA hybridization. Prospect of kelp bioreactor producing high value materials such as edible HBV vaccine was discussed as well.     

海带多糖生物活性的研究进展

海带多糖是一种特有的含有硫酸酯的天然活性多糖,本文就它的抗凝血、抗肿瘤、抗病毒、抗血栓、提高免疫力等生物活性进行了全面阐述。     

海带和裙带菜对鼠乳腺发育调控的研究

利用组织学技术研究海带（Laminaria japonica Aresch）和裙带菜(Undaria pinnatifida Harv.）在昆明系小鼠乳腺发育过程中的作用时发现，海带和裙带可明显提高鼠的受孕率，是对照组的2．5倍；刺激和加速乳腺上皮繁殖产生许多新的腺泡，这些腺泡的细胞在短时间内不断分裂，体积不断增大，细胞变为柱状或锥形，泡腔内储量有大量的乳汁。这种调节作用使乳腺快速进入授乳期。     

Programmed cell death in Laminaria japonica (Phaeophyta) tissues infected with alginic acid decomposing bacterium

TdT-mediated dUTP-biotin nick end labeling (TUNEL) is a sensitive and valid method for detecting DNA cleavage in programmed cell death (PCD). Using this method, DNA cleavage was observed in Laminaria japonica sporophytic tissues, which were infected with alginic acid decomposing bacterium. It was found that DNA cleavage occurred 5 min after the infection, the fragments with 3′-OH groups of cleaved nuclear DNA increased with time of infection and spread from the infection site. Although no typical DNA ladder (200 bp/180 bp) was detected by routine agarose gel electrophoresis, the cleavage of nuclear DNA fragments of 97～48.5 kb could be detected by pulsed field gel electrophoresis (PFGE). By using CaspGLOWTM fluorescein active caspase-3 staining method, caspase-3 activity has been detected in response to the infection of alginic acid decomposing bacterium. Our results are similar to the observations in hypersensitive response (HR) of higher plant, suggesting that the rapid cell death of L. Japonica infected by alginic acid decomposing bacterium might be involved in PCD, and indicating that the occurrence of PCD is an active defense process against the pathogen's infection.     

超临界萃取法提取海带多不饱和脂肪酸的研究

对以海带（Laminaria japonica)为原料,采用超临界CO2萃取技术提取海藻多不饱和脂肪酸的可行性进行了研究,结果表明,当CO2流量2．5－3．5L／h,萃取压力25MPa,萃取温度30℃,萃取时间3h,原料粒度40－60目,分离压力5MPa和分离温度35℃时最利于海带脂质的提取,此萃取条件可使海带总脂肪酸中多不饱和脂肪酸含量达到67．2％。     

九孔鲍摄食海带的能量收支研究

在室内水族箱投喂新鲜海带养殖九孔鲍(Haliotis diversicolor aquatiliis)．实验结果表明，个体耗氧率在夜晚高，白天低，最高是在17：30～2l：30．摄食能(C)中，只有少部分(2.60％)的能量用于软体部和壳的生长，而很大一部分能量(52．86％)是在代谢能(R)中，排泄能(U)、排粪能(F)、粘液(M)和壳能(Pah)分别占摄食能的9．69％、12．33％、6．61％和0.26％，鲍能量收支方程为：100％(C)=12．33％(F) 5286(R)％ 9．69％(U) 6．61％(M) 2.33％(Pg) 0．26％(Pah) 15．90％。     

功能性海带低分子量岩藻多糖研究进展

海带是我国最丰富的海藻资源之一,来源于海带的低分子量岩藻多糖有溶解性好、黏度低、易吸收等特点,且具有抗肿瘤、抗氧化、保护肝脏、降低血压等多种生物学功能,被广泛应用于医药、食品等领域.着重介绍了海带低分子量岩藻多糖的生物学功能及其制备技术的研究进展.     

海带多糖中蛋白质去除方法的对比研究

采用4种方法对海带多糖进行了脱蛋白研究,并比较了脱蛋白效果与多糖损失之间的关系.结果表明:这四种方法脱蛋白效果优劣顺序依次为蛋白酶解法、三氯乙酸沉淀法、鞣酸沉淀法和Sevag法.脱蛋白过程中使蛋白质沉淀的机理可能是造成多糖损失的主要原因,蛋白酶解法脱蛋白效果最好且多糖得率最高.     

Study on the enzymatic activity of Caspase-3 in response to alginic acid decomposing bacteria in Laminaria japonica Aresch.（Phaeophyta）

Caspase-3 is the major factor in apoptosis triggered by various stimuli, and plays a critical role during the apoptosis process. By using CaspGLOWTM fluorescein active caspase-3 staining method, caspase-3 enzymatic activities were detected in response to alginic acid bacteria in Laminaria japonica sporophytic tissues. Results showed that caspase-3 enzymatic activities were observed at 5 min after the infection. Caspase-3 enzymatic activity increased with the infection time, and had a tendency of moving from the infection site to outside. By applying caspase-specific peptide inhibitor Z-VAD-FMK, caspase-3 activation could be effectively abolished in the infected tissues. Our results indicate that programmed cell death (PCD) may be involved in the infected Laminaria japonica sporophytic tissues, and provide the evidence that defense mechanisms in algae may have similar caspase cascade events in animals.     

TA乳粉对海带生长产量及品质的影响

于１９８９～１９９２年，在大连黑石礁场，用不同浓度ＴＡ乳粉浸海带苗，可在其生长最关键时期充分发挥药效，提高其日生长量及制干率，从而提高产量。处理的海带厚度、宽度及色泽均优于对照，提高了等级率。海带中甘露醇、褐藻酸钠、碘、蛋白质、脂肪、糖、Ｖｃ含量的增加，提高了海带的药用、工业及营养价值，并能提前１０ｄ左右收获。用ＴＡ乳粉１×１０－６（体积百分比浓度）处理１２ｈ及２×１０－６处理２ｈ是达到两高一优的最佳措施。