5种樱桃属植物的POD、CAT和SOD同工酶分析

采用聚丙烯酰胺垂直平板凝胶电泳技术对5种樱桃属植物的过氧化物酶(POD)同工酶、过氧化氢酶(CAT)同工酶和超氧化物歧化酶(SOD)同工酶的酶谱特征进行分析,结果表明:5种樱桃属植物共电泳出12条POD同工酶酶带、4条CAT同工酶酶带和8条SOD同工酶酶带;其中,POD同工酶酶谱具有5条共同谱带,CAT同工酶4条,SOD同工酶5条。冬季休眠期的樱桃属植物,POD与SOD同工酶谱带的多样性比较丰富,不同植物之间的谱带差异较大;而CAT同工酶谱带差异不明显。     

发菜膜脂及其脂肪酸组成

对野生发菜(Nostocflagelliforme Bom.et Flab)的膜脂(主要成分为类囊体膜脂)及其脂肪酸组成进行了测定分析.发菜的膜脂由单半乳糖甘油二酯(MGDG)、双半乳糖甘油二酯(DGDG)、磷酯酰甘油(PG)和硫代异鼠李糖甘油二酯(SQDG)组成,其酯酰基连接有棕榈酸(16:0)、十六碳烯酸(16:1)、硬脂酸(18:0)、油酸(18:1)、亚油酸(18:2)和亚麻酸(18:3)6种脂肪酸.发菜的不饱和脂肪酸含量可达总脂的73%,特别是16:1和18:3分别高达29%和34%,远远高于已报道的其他蓝藻,说明了发菜类囊体膜具有较强的抗逆性特点.同时还对复水30 min和复水后生长24 h的发菜膜脂及其脂肪酸组成进行了分析.结果表明,复水对野生发菜的膜脂及其脂肪酸组成没有显著影响,说明发菜的膜脂和脂肪酸组成在干燥-吸水过程中能保持很高的稳定性.     

10种海洋微藻总脂、中性脂和极性脂的脂肪酸组成

研究了10种海洋微藻的总脂、中性脂和极性脂的脂肪酸组成特征。海洋微藻的脂肪含量均在15％以上。极性脂一般为海洋微藻的主要脂类,是长链多元不饱和脂肪酸的主要提供者。中性脂含短链脂肪酸较多,为主要的储存脂类。绿藻纲可以将高含量的16:4(n-3)和18:3(n-3)作为化学分类的标记脂肪酸,小球藻和微绿球藻有丰富的20:5(n-3),与绿藻纲显著不同,可能属于大眼藻纲。绿枝藻纲的脂肪酸组成与绿藻纲类似,绿胞藻纲以16:0、18:4(n-3)和20:5(n-3)为主要脂肪酸。脂肪酸组成可用于海洋微藻的分类学研究,并能指导利用海洋微藻生产高度不饱和脂肪酸。     

Na2SO4胁迫对四种抗盐性不同牧草膜脂过氧化和活性氧清除系统的影响

 经过1%和2%的Na2SO4胁迫后,草原绢蒿,圆叶蒿,苇状羊茅和鸭茅4种牧草的膜脂过氧化程度和质膜的透性都增加,但抗盐性较强的草原绢蒿和苇状羊茅的膜脂过氧化程度及质膜透性分别低于同科中抗盐性较差的圆叶蒿和鸭茅。随着Na2SO4胁迫浓度的增加,两种禾本科牧草的超氧化物歧化酶(SOD)及过氧化氢酶(CAT)的活性逐渐升高,两种菊科牧草的SOD及CAT的活性却逐渐下降,但禾本科中抗盐性较强的苇状羊茅的SOD及CAT活性的增长率要大于抗盐性较差的鸭茅,菊科中抗盐性较强的草原绢蒿的SOD及CAT活性的下降率要小于抗盐性较差的圆叶蒿。在Na2SO4胁迫下,两种抗盐性较强牧草的类胡萝卜素的相对含量要分别高于同科中抗盐性较差的牧草。     

内蒙古科尔沁沙地两种沙生植物冷蒿和差不嘎蒿竞争策略的生理生态学依据(英文)

Gas exchange, water relations and leaf chemical characteristics were examined of twodominant psammophytes: Artemisia frigida Willd and A halodendron Turcz. ex Bess in Horqin sandy land, NeiMongol, China under different water regimes. The measurements were conducted by submitting the plantsto five different irrigation levels. A. fTigida was characterized by lower photosynthetic rate (Pn), lowertranspiration rate ( TR and lower shoot water potential (ψuw) relative to A. halodendron. Foliage of A frigdahad higher values of relative water deficit (RWD), bound water content (BWC), ratio of bound water contentto free water content (BWC/FWC) and integrated drought-resistant index (DI than that of A. halodendron.Water relations differed significantly between two species in response to soil water availability. ψw, BWCand BWC/FWC ratio of A halodendron exhibited large variation with gradual decrease of soil moisture.However, in terms of these parameters, A. fRIGIDA was characterized by higher capacity of water holding anddrought tolerance relative to A halodendron. Proline and total soluble sugar contents of A frigida and Ahalodendron tended to increase with decrease of soil moisture and the former had a larger increaseamplitude than the latter. This shows that A frigida has a higher osmotic regulation ability than A halodendron.Under the extreme drought conditions, ψw, RWD, BWC and BWC/FWC of two species were approximate,but soluble proteins degraded largely. A large amount of accumulation of organic matter, proline and totalsoluble sugars were observed in both A halodendron and A frigida. The increase in proline and total solublesugar contents and soluble protein degradation of A frigida far exceeded those of A. halodendron. Webelieve that the accumulated materials at this moment are mostly of nutrient substances available for therecovery of plants after the drought. This is one of the reasons why A halodendron plants died while Afrigida plants survived under extremely drought condition. Our results suggest that these ecophysiologicalfeatures of A frigida are favorable to its growth in the fixed sandy land compared with A halodendron, whichoften lost its dominance due to weak competition for water sources under lower soil water availability andare major factors resulting in replacement of A. halodendron by A. frigida in the later stage of sandyvegetation succession in Horqin.     

两种水华藻——球形棕囊藻和铜绿微囊藻的脂肪酸组成特征与水华形成机制

浮游植物所含的不饱和脂肪酸是测定其作为食物质量的指标,并在浮游植物向浮游动物及其它动物能量转化过程中起着关键的作用,必需不饱和脂肪酸的缺乏有利于水华的形成。球形棕囊藻(Phaeocystis globosa)和铜绿微囊藻(Microcystis aeruginosa)分别是常见的海洋和淡水水华藻类,该文分析了它们在不同生长期的脂肪酸组成,探讨了这两种藻类的脂肪酸组成特征。球形棕囊藻和铜绿微囊藻的脂肪酸碳链长为14~20个碳原子,脂肪酸种类组成都比较简单,以饱和脂肪酸为主,未检测到二十碳五烯酸(Eicosapentaenoic acid,EPA)和二十二碳六烯酸 (Docosahexaenoic acid,DHA)等动物的必需脂肪酸。球形棕囊藻的总脂肪酸含量在247.294~735.44 μg·g^-1干重之间,在对数期和延滞期含量最高的脂肪酸分别是C14:0和C16:0;而两株铜绿微囊藻的总脂肪酸在1 405.095~6 087.617μg·g^-1干重之间,以C16:0含量最高。两株铜绿微囊藻的脂肪酸含量在对数期和延滞期差异明显(p<0.05),但球形棕囊藻的脂肪酸含量在不同生长期差别不大。由于缺乏必需脂肪酸EPA和DHA,球形棕囊藻和铜绿微囊藻不能为高营养级的生物提供必需的不饱和脂肪酸,不是浮游动物等生物的良好食物。因此球形棕囊藻和铜绿微囊藻作为浮游动物的食物质量较低,浮游动物对它们的捕食压力也较小,可能是这两种藻容易暴发水华的重要原因。     

春玉米叶片衰老中激素变化,Ca^2＋跨膜运输和膜脂过氧化三者之间的关系

通过离体玉米（ZeamaysL．）叶片培养和叶肉质膜微囊45Ca2 吸收等实验,探索春玉米叶片衰老过程中激素变化、Ca2 跨膜运输及膜脂过氧化三者之间的联系。结果认为,玉米叶片衰老的可能过程首先是内源激素含量变化,继而影响到Ca2 跨膜运输,进而导致膜脂过氧化,由此引起叶绿素和蛋白质降解。     

植物多糖抗肿瘤作用与机理研究——Ⅲ、茯苓多糖(PPS)和刺五加多糖(ASPS)对S180细胞膜脂肪酸组成的影响

我们先前的研究表明,植物多糖抑制体外培养的小鼠肉瘤S180细胞增殖并使细胞膜磷脂含量减少,同时抑制膜磷脂酰肌醇转换。为进一步探讨植物多糖与膜磷脂的关系,本文采用毛细管柱气相色谱法分析了茯苓多糖(PPS)、刺五加多糖(ASPS)与S180细胞一同温育24h后,细胞膜磷脂和中性脂的脂肪酸组成变化,发现中性脂的脂肪酸组成和不饱和性不受影响,磷脂的脂肪酸组成发生明显改变,花生四烯酸(C(20:4))和豆蔻酸(C(14:0))降低(P<0.05或P<0.01),与用作阳性药物对照的氨甲喋呤作用相似。本文对膜磷脂脂肪酸组成变化的意义结合先前的实验结果进行了讨论,认为在PPS、ASPS的抗肿瘤机理中,细胞膜磷脂生化特性的改变是重要环节。     

两种五倍子蚜虫冬寄主藓类植物的光合特性及其与光照,温度和？…

The net photosynthesis of Thuidium cymbifolium and Chrysocladium retrorsum, two species of wintering host mosses for gullaphids, and its response to light, temperature and water content were measured with CI-301PS(CID Inc. USA) both in winter and spring. The photosynthetic capacity of Thuidium cymbifolium and Chrysocladium retrorsum was about 141 and 117 mumolCO2kg-1dw.s-1, respectively, and trended to increase from winter to spring. The light saturation point of these two mosses at 800-900 mumol.m-2.s-1 was much higher than that of many other mosses, and the compensation point ranged from 40 to 50 mumol.m-2.s-1. The temperature response curves of these two mosses were similar, with optium temperature ranging from 25 to 36 degrees C in spring, and from 20 to 30 degrees C in winter. When the temperature was below the freezing point(-15 to 0 degree C), they both maintained a distinct net photosynthesis, with the optimum water content ranging from 200 to 300(400)% dw. The photosynthesis started to be restrained evidently, when the water content declined to about 150% dw. The gas exchange ceased or became negative, when the water content was as low as 40-50% dw. It can be inferred that these two species might be both poikilothermal and poikilohydric organisms, but the resistibility of T. cymbifolium to intense light and high temperature was higher than that of C. retrorsum.     

高寒山区牧草根质膜和脂肪酸组分对冷冻低温的适应反应

在秋末冬初测定了高寒山区自然生境中生长的垂穗披碱草(Elymus nutans)、早熟禾(Poa sphyondylodes) 和花雀麦(Bromus sinensis)3种牧草根膜脂脂肪酸组分和质膜流动性及ATPase活力。结果表明：随着秋末冬初气温下降到0℃以下,3种牧草根中膜脂肪酸配比发生较大变化,棕榈酸相对百分含量下降40.29％,亚油酸增加3倍多,亚麻酸增加112.39％,脂肪酸不饱和指数(IUFA)增大;同时根质膜流动性在低温期间较大,在融冻阶段有下降,冰冻阶段增大;质膜Mn2+ATPase、Ca2+ ATPase活力增大,Mg2+ ATPase活力下降。在冷冻适应中牧草根膜脂脂肪酸不饱和度的增加直接影响着膜的流动性,影响膜功能和植物抗冻性,并在维持根细胞膜完整性和抵抗组织结冰伤害方面起重要作用。     

人红细胞膜和血浆游离脂肪酸成分分析及其对膜微粘度的影响

采用高效液相色谱（ＨＰＬＣ）和荧光偏振技术测定了４２例正常人红细胞膜和血浆游离脂肪酸（ＦＦＡ）及膜微粘度,并探讨了膜脂肪酸和血浆ＦＦＡ构成与膜微粘度之间的关系。结果表明：正常人红细胞膜主要由廿二碳六烯酸（Ｃ２２∶６）、花生四烯酸（Ｃ２０∶４）、亚油酸（Ｃ１８∶２）、软脂酸（Ｃ１６∶０）、油酸（Ｃ１８∶１）和硬脂酸（Ｃ１８∶０）等六种脂肪酸组成。血浆ＦＦＡ构成与膜脂肪酸相似,但不含Ｃ２２∶６而含十四烷酸（Ｃ１４∶０）。红细胞膜各脂肪酸含量大多与其血浆浓度呈明显正相关。红细胞膜微粘度与膜软脂酸和硬脂酸呈明显正相关,与膜廿二碳六烯酸和花生四烯酸呈明显负相关。提示红细胞膜脂肪酸组成受血浆ＦＦＡ成分影响;而红细胞膜脂肪酸成分对膜微粘度亦有重要影响     

麻醉瓜成熟与衰老期间内源激素的变化与呼吸作用的关系

本文对麻醉瓜采收前后及衰老期间的呼吸强度、乙烯生成及内源生长调节物质作了测定。麻醉瓜成熟过程中 ABA 首先生成并积累,当 ABA 达到一定水平后才出现乙烯的生成。与杏果相似,麻醉瓜成熟期间果肉中 ABA 大量积累,生长促进物质迅速消失,这可能是它不耐贮藏的内在生理原因。     

黄檀属两种树木形成层的活动周期和次生韧皮部的季节变化

观察了南岭黄檀（Ｄａｌｂｅｒｇｉａ ｂａｌａｎｓａｅ Ｐｒａｉｎ）主干、思茅黄檀（Ｄ．ｓｚｅｍ ａｏｅｎｓｉｓＰｒａｉｎ）枝条形成层活动的周期,次生韧皮部的季节变化和筛管寿命。结果表明：１．形成层均为叠生型。２． 南岭黄檀形成层于４ 月末开始分裂,１１月初停止活动。韧皮部于１１ 月初完成分化,木质部到１２月才完成分化。思茅黄檀形成层于４ 月中旬到１０ 月下旬活动,１１ 月下旬韧皮部和木质部都已完成分化。３． 具功能韧皮部区在秋季最宽,达４００—６００ μｍ ;２—４ 月最窄,仅为２００—３７０μｍ ,此时筛管分子仍具Ｐ－蛋白质,筛板孔开放。４． 南岭黄檀、思茅黄檀的筛管寿命分别为８—１２ 个月和９—１１ 个月。５． 形成层休眠时韧皮薄壁组织细胞中有淀粉与草酸钙结晶积累,形成层活动时量渐减少,夏季很少或无     

荒漠植物梭梭和沙拐枣的花环结构及C4光合特征

 为了探讨梭梭（Haloxylon ammodendron）和沙拐枣（Calligonum mongolicum）适应高温强光荒漠环境的光合作用机构及特征,通过对其同化枝的解剖结构观察,δ13C值分析,以及气体交换测定表明：二者均具有花环结构(Kranz anatomy),肉细胞（Mesophyll cell）呈栅栏状,其内侧是维管束鞘细胞（Bundle sheath cell）,小维管束与维管束鞘细胞相接。在栅栏组织和贮水组织中,梭梭具有形状巨大的含晶细胞;沙拐枣具有大量的粘液细胞。梭梭和沙拐枣同化枝的δ13C值分别为-14.3‰和-14.8‰,在不同生长季节和土壤水分条件下,二者的δ13C值变化在-14‰到-16‰之间。梭梭和沙拐枣的CO2补偿点分别为2 μmol•mol－1和4 μmol•mol－1,光饱和点分别为1 660和1 756 μmol•m－2•s－1,表观光合量子效率分别为0.044和0.057 mol CO2•mol－1 photons。这表明,广泛分布于我国荒漠地区的木本植物梭梭和沙拐枣为C4植物,其光合途径不随生长季节和水分条件的变化而改变。     

SEASONAL CHANGES IN THE PROXIMATE AND FATTY ACID COMPOSITION OF SOME NATURALLY GROWN FRESHWATER CHLOROPHYTES1

The protein content of the filamentous Cladophora glomerata (L.) Kz., Ulothrix zonata (Web, & Mohr) Kz. and Spirogyra sp., collected from natural populations for 1 year, averaged 8.0–12.4% of the total dry weight; whereas, the corresponding levels of lipid, cellulose and ash were 11.9–16.1%, 10.0–17.8% and 14.6–24.0%, respectively. Mean values for carbohydrates, estimated by difference, ranged from 32.8 to 56.0%. The colonial Scenedesmus dimorphus (Turp.) Kz. and the unicellular Cosmarium laeve Rab., on the other hand, contained more protein, lipid and carbohydrate (estimated by difference) averaging 13–15.0%, 22.5–25.9% and 415–46.8%, respectively, and less cellulose (7.5–9.8%) and ash (8.2–9.8%). A consistent pattern of seasonal variation in the proximate composition was not normally evident for any species, reflecting the influence of several environmental parameters on the algae. Cladophora contained the greatest amount of phospholipid averaging; 10% by weight of total lipid with the smallest quantity (5%) in Scenedesmus. The predominant phospholipid fatty acid in all species was C_18:1 followed by C_18:2, C_18:3 and C_16:1 in Cladophora, Ulothrix and Spirogyra, and C_16:1, C_18:2 and C_16:0 in Scenedesmus and Cosmarium. Oleic (C_18:1) and hexadecanoic (C_16:1) acids were predominant in the neutral lipids of all the algae, followed by C_16:0, C_18:2 and C_18:3. The concentration of the different fatty acids of each Species varied considerably during the year with the proportion of C_16:0 and C_16:1, usually rising and that of C_18:1 failing during the colder months.     

鄂尔多斯高原库布齐沙地三趾跳鼠静止代谢率的季节变化

三趾跳鼠的代谢率存在季节性变化 ,春季的静止代谢率最低 (0 75mlO2 /h .g) ,仅为期望值的 6 4% ,热中性区最窄 (2 9～ 31℃ ) ;夏季的代谢率 (1 17mlO2 /h .g)与期望值一致 ,热中性区最宽 (2 8～ 37℃ ) ;秋季的代谢率 (1 31mlO2 /h .g)高于期望值 10 % ,热中性区向低温偏移 (2 6～ 30℃ )。三趾跳鼠各季节的体温从春季到秋季逐渐降低 ,并且在环境温度为 30℃以下时基本维持恒定 ,高温时动物以耐受一定程度的高体温和分泌唾液防止致死性过热。三趾跳鼠的能量代谢特征不仅与季节性食物和环境温度变化有关 ,而且与该鼠种的冬眠特性也有一定联系     

低温驯化下锯缘青蟹肝胰腺蛋白质表达及脂肪酸组成的变化

锯缘青蟹(Scylla serrata)在不同低温下经3周驯化后,采用双向电泳(Two division electrophoresis,2D-E)和气相色 谱(Gas chromatography,GC)分别对肝胰腺中蛋白质表达和脂肪酸组成变化进行研究,结果发现5℃驯化组与27℃组 相比,肝胰腺中共有22种蛋白的变化,其中5℃驯化组有15种蛋白在27℃组没有检出,而27℃组有7种蛋白在5℃ 驯化组没有发现;10℃驯化组与27℃组相比,共有18种蛋白变化,10℃驯化组有14种蛋白在27℃组没有检出,27℃ 组有4种蛋白在10℃驯化组没有出现;锯缘青蟹15℃驯化组与27℃组相比,肝胰腺中有6种蛋白质有变化,其中驯 化组分离出5种在27℃组没有检出的蛋白质,27℃组分离出1种在驯化组没有出现的蛋白质。27℃组没有检出,仅 在驯化组中出现的蛋白质中,经Imagemaster2D Elite软件分析后发现5℃和10℃驯化组有14种蛋白质在图谱上是匹 配的(即是同样的),15℃驯化组表达的5种蛋白与5℃驯化组和10℃驯化组表达的蛋白不匹配。低温驯化3周后 锯缘青蟹肝胰腺中饱和脂肪酸∑SFA在5℃和10℃驯化组显著低于27℃组(P<0．05),而∑UFA在5℃和10℃驯化 组显著高于27℃组(P<0．05),相应地5℃和10℃驯化组饱和指数∑SFA/∑UFA也显著低于27℃组(P<0．05),其 主要是∑PUFA-ω6低温驯化下显著升高(P<0．01)所致。结论表明锯缘青蟹不同低温驯化下,肝胰腺细胞中蛋白 质表达是一种动态变化模式。驯化温度越低,差异蛋白变化越大。低温驯化下脂肪酸饱和指数降低,主要是维持 低温下肝胰腺正常的生理功能。     

缓慢干旱下春小麦叶片质膜脂肪酸组成、H~+-ATPase肥及5′-AMPase活力的变化

研究了田间缓慢干旱胁迫下,抗旱性不同的两个小麦(Triticum aestivum)品种的生长状况、质膜极性脂脂肪酸组成以及质膜关键酶活力的变化。在小麦生长发育的早期,干旱胁迫使其叶片质膜极性脂脂肪酸不饱和度下降、质膜微囊消耗O_2的速率升高、膜蛋白含量降低、H~+-ATPase(EC 3.6.1.35)活力下降、5′-AMPase(EC 3.1.3.5)活力大幅度升高;在小麦发育的后期,随着干旱的持续,小麦叶片质膜的极性脂脂肪酸不饱和度不变或升高、质膜微囊消耗O_2的速率降低、膜蛋白含量与H~+-ATPase活力升高、5′-AMPase活力下降。以上结果表明,小麦在发育的早期阶段对干旱较敏感,其细胞质膜流动性降低、细胞中能荷贮备降低;而在后期,则又表现出对干旱的适应。这些结果将有助于阐明自然干旱条件下植物的抗旱机制。