【作者】 周革非；

【导师】 徐祖洪；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋化学， 2004， 博士

【摘要】 角叉菜，属红藻门，杉藻科，角叉菜属，自然分布于大西洋沿岸和我国东南沿海以及青岛、大连等海域，是中国的一种重要经济海藻。角叉菜不仅是卡拉胶生产的重要原藻，而且近年来越来越多地应用于医药领域，引起人们的广泛关注。 本文对采集于青岛太平角的皱波角叉菜的化学组成进行了较全面系统的分析。角叉菜中蛋白质和多糖含量高，脂肪含量低，还含有大量的人体所必须的微量元素，角叉菜中氨基酸含量很高，而且多是结合氨基酸。另外，为了探讨角叉菜的活性成分，采用 GC-MS 法分析了角叉菜的乙醇提取物和氯仿-甲醇提取物的化学组成。 本文在实验室分析方法的基础上，对其提取、分级条件进行了优化，确定了制备方法；并首次采用密闭微波法对获得的角叉菜λ-卡拉胶进行降解，获得五个不同分子量的降解产物，并对降解产物进行了红外、紫外和核磁共振分析，确定了降解产物的结构和分子量范围。 本文在第四章和第五章分别研究了五个不同分子量的角叉菜λ-卡拉胶的体内抗肿瘤活性和对化疗药物的抗肿瘤活性的影响，并测定了各组实验小鼠的多种免疫指标。证实了角叉菜λ-卡拉胶显著的体内抗肿瘤活性和免疫调节活性,同时能增强化疗药物的抗肿瘤能力，并有效抵抗其导致的免疫功能低下。 为探讨角叉菜λ-卡拉胶的抗肿瘤和免疫增强活性机理。本文（1）采用化学比色法研究了角叉菜λ-卡拉胶的体外抗氧化活性，证明角叉菜λ-卡拉胶具有显著的抗氧化活性，尤其是对小鼠肝匀浆脂质过氧化的抑制作用非常显著。（2）采用 MTT 法研究了角叉菜λ-卡拉胶体外对脾细胞活性的影响。角叉菜λ-卡拉胶能显著提高大鼠脾细胞自发增殖活性和刀豆蛋白（ConA）诱导的脾细胞增殖，对紫外线所致脾细胞损伤有很好的修复作用。其对免疫细胞的修复作用很可能与其显著的抗氧化活性有关。（3）采用 MTT 法研究了不同浓度的角叉菜λ-卡拉胶体外对白血病 YAC-1, 宫颈癌 HeLa 和肝癌 H-7402 细胞，以及小鼠腹水传代的肝癌 H-22 和肉瘤 S180 的体外抑制作用进行了研究，结果表明，不同分子量的角叉菜λ-卡拉胶在一定浓度下对各种肿瘤细胞均有一定的体外抑制活性。（4）采用鸡胚新生血管模型初步研究了角叉菜λ-卡拉胶对肿瘤新生血管生长的没有明显的抑制作用，证实了其抗肿瘤机理并非通过抑制新生血管生长来实现。 因此，不同分子量的角叉菜λ-卡拉胶具有显著的体内抗肿瘤活性，并能提高化疗药物的抗肿瘤效果，有效抵抗化疗药物引起的免疫功能低下。其抗肿瘤机理是通过其自身对肿瘤细胞的杀伤作用和提高机体的免疫系统功能来实现的，而提高机体免疫系统功能很可能与其显著的抗氧化活性有关。更多还原

【Abstract】 Chondrus ocellatus, distributes naturally in intertidal zone of Atlantic coasts,Chinese southeast, Qingdao and Dalian coast areas. Chondrus ocellatus was not onlyan important economic alga that can produce carrageenan, but also used as a medicineto cure chronic constipation and bone fracture in recent years. It was an importanteconomically valuable alga in China and has lead to more and more attention. In thisdissertation, we analyzed the chemical compositions of Chondrus ocellatus collectedon the seaside of Taiping Cape in Qingdao, optimized the procedure of the extraction,fraction and microwave degradation of λ–carrageenan from Chondrus ocellatus. Thebioactivities in vitro and in vivo were also studied. The basic chemical constituents and amino acid in Chondrus ocellatus wereanalyzed. It is high in protein and carbohydrates but low in fat. Chondrus ocellatuscontains many essential elements of which the human body is composed of. It alsocontains significant amounts of amino acid, most of them are complex amino acid. Inaddition, to study the bioactive chemical constituents in Chondrus ocellatus, thechemical components in the bioactivities of Chondrus ocellatus were extracted byethanol and chloroform-methanol, respectively, and were analyzed by GC-MSSpectrometry. At present, because of the limitation of its own characteristics, there is not highscale industry production of λ-carrageenans. In this paper, λ-carrageenan fromChondrus ocellatus was studied about extraction and fraction methods on the base oftheir analysis method. The optimum extraction procedure of λ-carrageenan wasdetermined. The airtight microwave method was first used on the degradation ofλ-carrageenan from Chondrus ocellatus, and obtained five products that have differentmolecular weight. IR, UV and NMR spectrum analytical results confirmed chemicalcomponents and structure of the degraded polysaccharides. In order to study bioactivities and effect of molecular weight on the activities ofλ-carrageenan, antitumor activities and the effect of λ-carrageenan on antitumorability of 5-Fu were investigated. The results of several immune targets indicated thatthe five λ-carrageenans all showed anti-tumor and immunomodulation activities in 2<WP=7>博士论文 角叉菜的化学组成和抗肿瘤活性different degree and could enhance anti-tumor activities of 5-Fu and improveimmunocompetence damaged by 5-Fu. In order to study the mechanism of antitumor and immunomodulation activitiesof different molecular weight λ-carrageenans, several experiments in vivo wereinvestigated on chapter 6, 7, 8 and 9. (1) The in vitro antioxidant activities of λ-carrageenan from Chondrus ocellatuswere investigated by chemical spectrometric methods. λ-Carrageenan with differentmolecular weight showed antioxidant activities, especially high scavenging activitieslipid peroxide of rat liver homogenate. Molecular weight of polysaccharides hadnotably effect on their antioxidant activities. (2) The immunoregulatory effects of different molecular weight λ-carrageenanson spleen cells were evaluated by MTT tetrazolium assay. The λ-carrageenans cannotably enhance lymphocyte proliferation spontaneously and induced by ConA. Theyalso can repair the injured spleen cells by ultraviolet ray. The functions may relevantto the notable antioxidant ability of the polysaccharides (3) The in vivo growth-inhibition of YAC-1, HeLa, H-7402 cells maintained invivo and H-22, S180 cells maintained in the peritoneal cavities of mice were evaluated by MTTtetrazolium assay. The results indicated that the λ-carrageenans from Chondrusocellatus with some concentration have antitumor activities in vivo. (4) The preliminary study on the effect of λ-carrageenans on angiogenesis in thechick embryo CAMS were investigated, and they had no notable inhibitory effect.This confirmed that an更多还原