Distributions and seasonal variations of dissolved carbohydrates in the Jiaozhou Bay,China   总被引：1，自引：0，他引：1  

Gui-Peng Yang  Yan-Ping ZhangXiao-Lan Lu  Hai-Bing Ding 《Estuarine, Coastal and Shelf Science》2010

Surface seawater samples were collected in the Jiaozhou Bay, a typical semi-closed basin located at the western part of the Shandong Peninsula, China, during four cruises. Concentrations of monosaccharides (MCHO), polysaccharides (PCHO) and total dissolved carbohydrates (TCHO) were measured with the 2,4,6-tripyridyl-s-triazine spectroscopic method. Concentrations of TCHO varied from 10.8 to 276.1 μM C for all samples and the ratios of TCHO to dissolved organic carbon (DOC) ranged from 1.1 to 67.9% with an average of 10.1%. This result indicated that dissolved carbohydrates were an important constituent of DOC in the surface seawater of the Jiaozhou Bay. In all samples, the concentrations of MCHO ranged from 2.9 to 65.9 μM C, comprising 46.1 ± 16.6% of TCHO on average, while PCHO ranged from 0.3 to 210.2 μM C, comprising 53.9 ± 16.6% of TCHO on average. As a major part of dissolved carbohydrates, the concentrations of PCHO were higher than those of MCHO. MCHO and PCHO accumulated in January and July, with minimum average concentration in April. The seasonal variation in the ratios of TCHO to DOC was related to water temperature, with high values in January and low values in July and October. The concentrations of dissolved carbohydrates displayed a decreasing trend from the coastal to the central areas. Negative correlations between concentrations of TCHO and salinity in July suggested that riverine input around the Jiaozhou Bay had an important effect on the concentrations of dissolved carbohydrates in surface seawater. The pattern of distributions of MCHO and PCHO reported in this study added to the global picture of dissolved carbohydrates distribution.  相似文献   

螺旋藻多糖对肿瘤细胞生长及Hela细胞早期凋亡作用的实验研究   总被引：1，自引：0，他引：1       下载免费PDF全文

于红  吕锐  张学成 《海洋科学》2008,32(1):38-40

采用MTT法(四甲基偶氮唑盐比色法)研究了钝顶螺旋藻多糖(PSP)对Hela细胞及HepG2细胞生长的抑制作用。结果表明,随PSP浓度及培养时间的增加,肿瘤细胞存活率逐渐降低,抑制率逐渐增加,以PSP40 mg/L作用72 h最为显著。应用Annexin V/PI双染色流式细胞仪检测了早期Hela细胞凋亡,未经PSP处理的正常Hela细胞凋亡细胞极少,经PSP处理的细胞,凋亡细胞的百分比明显高于正常对照组,其作用随着剂量的增加和时间的延长而增强,具有量效关系和时效关系。结果说明PSP的抗肿瘤机制,除了诱导肿瘤细胞凋亡,还存在细胞毒性等其他机制,是多种机制共同作用的结果。  相似文献   

长松藻基本营养成分分析及其多糖的提取     

熊皓平  黄涛  吉宏武  邵海艳 《广东海洋大学学报》2007,27(3):82-85

对南海长松藻(Codium cylindricum Holmes)的主要营养成分进行了分析,结果显示:多糖、蛋白质和粗纤维是构成藻体的主要营养成分,占藻体干基的80%左右,其中多糖占55.57%、粗纤维占11.09%、蛋白质占12.57%,但脂肪含量仅为0.59%。水溶性营养成分较为丰富,水浸出物总量为34.55%,其中包括水溶性蛋白、水溶性多糖、游离氨基酸等。多糖是长松藻的主要有效成分。单因素及正交实验结果表明:长松藻多糖提取的最佳工艺参数为浸提温度95℃,浸提时间1.5 h,料水质量比1∶50,多糖得率为9.79%。  相似文献   

Symbiotic Relations of Sediment-Agglutinating Nematodes and Bacteria in Detrital Habitats: The Enzyme-Sharing Concept   总被引：2，自引：0，他引：2  

Franz Riemann  & Elisabeth Helmke 《Marine Ecology》2002,23(2):93-113

Abstract. A new concept (‘enzyme sharing’) concerning the interaction of marine nematodes and microbes in the degradation of sedimentary detritus is presented. Elements of this concept are (1) the notorious tendency of many aquatic nematodes to agglutinate detrital particles by mucus secretions, (2) new observations on the stimulation of microbial growth by nematodes in agar plates, and (3) literature data on limited endogenous proteolytic capacities of aquatic nematodes.
Observations on nematode‐microbe associations in agar plates prompted the conceptual synthesis. In agar medium without the addition of any nutrients a spectacular growth of bacteria was visible on the sinusoidal crawling trails of nematodes only 2 – 3 days after introduction of the worms (species of Adoncholaimus, Anoplostoma and Sabatieria). Juveniles of Anoplostoma that hatched in the agar cultures left their minute trails in the medium and these were rapidly occupied by bacteria. The nematodes repeatedly visited their bacterial trails, which persisted as a peculiar biotic structure for more than one year and survived the nematodes.
In sterile agar preparations containing the fluorogenic methylumbelliferyl‐β‐glucoside in the presence of the nematode Adoncholaimus, an enhanced fluorescence of the medium was visible, indicating β‐glucosidase activity. We therefore assume that oncholaimid nematodes discharge enzymes that alone, or in concert with microbial activities, contribute to the hydrolytic cleavage of refractory polysaccharides containing β‐glucosidic bonds such as agar components and cellulose. The sugars thus produced may then be taken up by the nematodes and concomitantly support the conspicuous growth of microbes. Since we did not observe any feeding of the nematodes on the associated microbes in agar plates, we question the nutritive potential of intact microbial cells for a number of nematodes abounding in detrital habitats, and call attention to the significance of ambient dissolved or adsorbed organic monomeric nutrients.
Consequently, we perceive the puzzling perpetual accretion of detrital organic particles to sediment agglutinations by nematodes as an adaptation for operating an ‘enzymatic reactor’ for the production of dissolved nutrients. We hypothesise a relationship of mutual commensalism of nematodes and heterotrophic microbes in detrital habitats and propose the term ‘enzyme sharing’ for this relationship. Both parties invest in a common enzyme pool that decomposes organic detritus for their nutrition. We present here evidence that nematodes contribute β‐glucosidase, which is involved in the cellulase system. Data from the literature suggest that microbial enzymatic processing of detrital proteins yields amino acids available to nematodes, which apparently have no efficient proteolytic enzyme system in their intestines.  相似文献   

半叶马尾藻多糖对辐射损伤小鼠骨髓细胞集落生成的影响   总被引：3，自引：0，他引：3  

孟庆勇  刘志辉  郑辉 《中国海洋大学学报(自然科学版)》2005,35(3):503-506

探讨半叶马尾藻多糖[Sargassum hemiphyllum(Turner)C．Ag．polysaccharides，SHP]对辐射损伤小鼠骨髓细胞集落生成的影响。检测辐射损伤小鼠脾集落生成单位、红细胞集落生成单位、爆裂型红细胞集落生成单位、粒细胞．巨噬细胞集落生成单位、巨核细胞集落生成单位、混合集落生成单位的变化。5Gy7射线照射后小鼠CFU-S，CFU—E，BFU—E和CFU—Mix明显减少，而SHP(20mg／kg-40mg／kg)可以抑制CFU—S，CFU—E，BFU—E和CFU—Mix下降。辐射损伤也可以引起小鼠CFU-GM显著降低，但是，SHP(10mg／kg-40mg／kg)具有拮抗辐射损伤的作用，使CFU-GM增加。单纯照射组小鼠CFU—Meg显著低于正常对照组，SHP(40mg／kg)加照射组小鼠CFU-Meg却显著高于单纯照射组。SHP对辐射损伤小鼠多能干细胞和造血祖细胞具有保护作用。  相似文献   

钝顶螺旋藻藻蓝蛋白和多糖的抗肿瘤免疫活性研究   总被引：14，自引：2，他引：14  

李冰  张学成  高美华  于红 《中国海洋大学学报(自然科学版)》2004,34(3):396-402

对钝顶螺旋藻藻蓝蛋白 (PC)和多糖 (PSP)的抗肿瘤免疫活性进行了研究。采用免疫酶标技术、MTT法及定量溶血分光光度测定法等免疫分析实验 ,从免疫器官、免疫细胞、免疫分子 3个水平上进行藻蓝蛋白和多糖的抗肿瘤免疫活性检测。结果显示 ,藻蓝蛋白和多糖处理组小鼠瘤块直径及瘤体重量均小于对照组 ,T细胞及 B细胞活性明显增强 ,体液抗体量显著提高 ,螺旋藻藻蓝蛋白比多糖抑制肿瘤细胞生长和提高机体免疫力的作用更明显。  相似文献   

绿藻水溶性多糖的研究概况和进展   总被引：1，自引：0，他引：1  

李莎兰  洪亮  李诚博  刘晨光 《海洋科学》2016,40(9):145-151

对近年来绿藻多糖的提纯方法、组成结构及应用的研究进展进行了综述。绿藻多糖的提纯需要经过样品的前处理、提取和精制三个步骤,提取方法包括酸提、酶提、加入钙螯合剂提取、微波及超声波辅助提取。绿藻多糖是水溶性的硫酸化杂多糖。从石莼(Ulva)、浒苔(Enteromorpha)、礁膜(Monostroma)、小球藻(Chlorella)、蕨菜(Bracken)及刚毛藻(Bristles)中提取的多糖的化学组成及结构特征各不相同,而且多糖的化学组成和结构特征受提取方式的影响。绿藻多糖的生物相容性、生物可降解性及抗氧化、抗肿瘤、抗凝血、抗炎、免疫调节等多种生物活性使其在食品、医药、化妆品及农业中具有广泛的应用。有关绿藻多糖的精确结构、提纯方法及化学修饰的进一步研究将使绿藻多糖的应用更加广泛。  相似文献   

胶质芽孢杆菌胞外多糖在肥料矿物分解转化中的作用   总被引：3，自引：0，他引：3  

周雪莹  李辉  连宾 《矿物岩石地球化学通报》2010,29(1):63-66

本文探讨了胶质芽孢杆菌胞外多糖在细菌分解转化矿物过程中的作用。将事先提取的胞外粗多糖按一定浓度梯度与矿粉混合,24 h后再次提取多糖称重,证实多糖与矿粉颗粒之间的吸附现象。计算结果表明,矿粉对多糖的吸附随多糖量的增加而呈较明显的增长,之后增幅逐渐趋于平缓。在无氮培养基中添加不同种类矿粉培养细菌,然后分别提取粗多糖和较纯多糖,发现矿物种类对胶质芽孢杆菌多糖的分泌有显著影响。添加含有细菌所需矿质养料的矿粉在培养液中,胞外多糖含量相对增高,说明细菌分泌胞外多糖受到矿物化学组成的影响,即细菌胞外多糖的产生与它们对矿物养料的需求和矿物的风化过程有密切联系。  相似文献   

球等鞭金藻胞外多糖的体外抗氧化活性和理化性质的初步分析     

孙颖颖  王辉 《海洋科学》2013,37(5):45-49

前期研究采用离子交换柱层析和凝胶柱层析,制备到一种球等鞭金藻胞外纯多糖ECPSⅢ。在此基础上,采用化学比色法研究了 ECPSⅢ的体外抗氧化活性;同时,通过测定 ECPSⅢ中的硫酸基和糖醛酸含量,初步分析了ECPSⅢ的理化性质。结果表明, ECPSⅢ具有清除超氧阴离子(O2·ˉ)、羟基自由基(·OH)和过氧化氢(H2O2)等活性氧的能力和一定的还原力。其中, ECPSⅢ对O2·ˉ和·OH的清除能力较强。ECPSⅢ中的硫酸基和糖醛酸含量分别为76.90 mg/g和17.1%,是一种富含硫酸基和糖醛酸的酸性多糖。  相似文献   

海蒿子多糖的结构组分及生物活性研究     

李溢真  于志洋  田欣  宋琳 《海洋科学》2020,44(11):10-18

采用水提醇沉法制备海蒿子多糖，利用红外光谱法（FT-IR）和PMP柱前衍生化法研究海蒿子多糖的理化特性及糖元组成，并采用实时荧光定量PCR法和ELISA法，研究免疫相关因子和细胞凋亡相关因子的mRNA表达。结果表明，海蒿子多糖总糖含量为24.32%，硫酸根含量为5.39%，具有α糖苷键。单糖分析表明，海蒿子多糖主要由半乳糖、岩藻糖、甘露糖组成。进一步体外免疫实验结果表明，海蒿子多糖具有促进小鼠巨噬细胞RAW264.7增殖的作用，能够提高巨噬细胞系免疫因子IL-1β、IL-6、iNOS和TNF-α的mRNA表达量。此外，海蒿子多糖还能抑制肺癌细胞A549的增殖，提高Bax/Bcl-2的比例，说明其具有抑制肿瘤的效果。ELISA分析表明，海蒿子粗多糖能显著提高RAW264.7分泌NO、IL-1β、TNF-α和IL-6细胞因子。因此，海蒿子多糖不仅具有免疫增强活性，还具有一定的抗肿瘤活性。  相似文献