固定化细胞的混合糖连续发酵动力学模型

利用固定化啤酒酵母和固定化毕赤酵母在两个串联的固定床内连续发酵由葡萄糖和木糖组成的混合糖制取酒精的过程,建立了连续发酵的非结构动力学模型。该模型以带抑制项的米氏动力学方程为酶动力学基础,考虑了抑制物抑制、底物抑制、轴向弥散及膜传质等因素。成功地引入了一个综合考虑颗粒相内外传质的总有效因子简化模型的计算,并取得了较为满意的仿真结果。     

CHO细胞生长过程的建模及仿真研究

运用了一种以代谢协调和代谢调节概念为基础的生物工艺过程建模思想,以实际过程为背景建立了中国仓鼠卵巢细胞(CHO)的微载体培养生长模型,进行了仿真研究并得出了一些有意义的结论。     

微生物产生的木聚糖酶的功能和应用

术聚糖是一种异质多糖,主要由木糖和阿拉伯糖组成。微生物产生的木聚糖酶来源广泛,能将木聚糖水解为木寡糖和D-木糖。该酶具有极大的应用价值,如可用于纸浆的漂白以减少环境污染,也可将造纸工业及农业废料中的木聚糖转化为D-木糖。     

山楂种子体眠和萌发与营养物质植物生长物质关系的研究

对低温层积不同时期的山楂种仁中的氨基酸、植物生长物质等几项生理生化指标进行了定量分析的结果表明层积１５至１８个月时因缺水出现二次休眠,在种子内部发生一系列生理变化,从中得知脱落酸,吲哚乙酸为生长抑制剂,玉米素核苷,赤霉素为促进剂。脯氨酸对干旱比较明感,随着层积时间的延长营养物质趋于升高,酶的活性提高,为种子发芽提供了能量。     

2000年间野生稻和栽培稻(O.sativa.L)分布区逆向分离的过程及动力Ⅰ.古今野生稻和栽培稻(O.sativa.L)的分布与人口分布的关系

２０００ａ间,中国境内野生稻分布区域由２４９５５７５ｋｍ２缩减至１３７１０９４ｋｍ２,减少了４５．０６％;分布纬度北界由３８°３′Ｎ南移至２８°１４′Ｎ,南移９°４９′、１１４０ｋｍ;中国境内栽培稻分布区域由４０８１８６０ｋｍ２增加至９６０００００ｋｍ２,增加了１３５．００％;分布北界由３８°Ｎ北移至５３°２９′Ｎ,北移１５°２９′、１７００ｋｍ。人口分布重心主要在黄河流域和长江流域,对该区域野生稻的生存产生不利影响。而促进栽培稻的发展,必须建立野生稻自然保护区。     

变孢毛霉的一个新变种及对Mucor luteus Linnemann和M.variosporus Schipper的合格化(英文)

根据国际植物命名法规,对两个不合格发表的毛霉种名：Ｍｕｃｏｒ　ｌｕｔｅｕｓ　Ｌｉｎｎｅｍａｎｎ和ＭｕｃｏｒｖａｒｉｏｓｐｏｒｕｓＳｃｈｉｐｐｅｒ进行了合格化。对变孢毛霉（Ｍｉｃｏｒｖａｒｉｏｓｐｏｒｕｓ）的一个新变种进行了描述。     

出芽短梗霉菌株CBS591．75和DSM2404发酵生产聚苹果酸的研究

研究了出芽短梗霉蕾株CBS591.75和DSM2404在2L发酵罐中发酵生产聚苹果酸的过程。并以CBS591．75为菌种进行了20L规模的初步放大试验。结果表明,发酵过程可以分为3个阶段,第一阶段从接种开始。到发酵液的pH上升到最高点并开始下降为止．这一阶段中细胞缓慢增长,没有聚苹果酸产生;第二阶段以pH迅速下降和聚苹果酸大量产生为特征。这一阶段中聚苹果酸的产生与细胞增长相平行;在第三阶段中,聚苹果酸产生速度减慢．pH趋于稳定。试验结果还表明。菌株CBS591．75产生聚苹果酸的能力大于DSM2404,发酵结束时,前者聚苹果酸的产量为6．9g／L,而后者为5．4g／L。CBS591．75菌种在20L规模的初步放大试验表明,发酵144h后发酵液中聚苹果酸浓度为8．Og／L,稍高于2L发酵罐的结果,为今后的放大提供了依据和参考。     

枯草杆菌蛋白酶E的蛋白质工程

用定点突变和随机突变的方法,对枯草杆菌碱性蛋白酶E基因进行改造。突变后的基因插入大肠杆菌-枯草杆菌穿梭质粒pBE-2中,在碱性和中性蛋白酶缺陷型的枯草杆菌DBl04中进行表达,得到突变种的碱性蛋白酶．它们的突变位点分别是(M222A)、(M222A、N118S)、(M222A、N118S、Q103R)、(M222A、N118S、Q103R、D60N)。各突变种酶的性质测定 结果表明．M222A突变使酶抗氧化,N118S突变使酶增加热稳定性,Q103R和D60N突变虽然能增加酶的比活,但使酶的热稳定性大大下降,尤其是D60N突变使酶变得极不稳定。野生型碱性蛋白酶与(M222A)突变种的等电点均为8．92．而M222A,N118S)。(M222A,N118S ,Ql03R)和(M222A,118S．Q103R,D60N)突变酶分别为8.88．9.10和9．17。用Nsuc-AAPF-pNA作为底物时酶反应景适pH值为7.5～9.5,而用酪蛋白底物时最适pH值为10～12。     

星星草受精作用及其胚与胚乳早期发育的观察

利用常规石蜡切片法对星星草[Puccinellia tenuiflora(Griseb．)Scribn．et Merr．]受精过程及胚与胚乳的早期发育进行了观察,主要结论如下：(1)开花后2h,花粉管破坏1个助细胞,释放2个精子,精子呈逗点状。(2)开花后2～3h,2个精子分别移向卵细胞与极核。(3)开花后3～5h,精核分别贴附于卵细胞与极核的核膜上。(4)开花后5～10h,精核与卵核融合,雄性核仁出现,合子形成。(5)开花后5～6h,精核与极核融合,并出现雄性核仁,形成初生胚乳核,精核与极核的融合比与卵核融合要快。(6)开花后20h左右,合子分裂。(7)开花后8h,初生胚乳核。     

中国石蕊科地衣研究之——筛蕊属的订正研究

本文对产于中国的筛蕊属地衣在形态与化学方面进行了比较研究,订正了文献中一些错误鉴定及分布方面的错误记载。 研究结果表明,筛蕊属地衣在中国只有一种,即聚筛蕊：Cladla aggregata(Sw·)Nyl。其主要特征为拟果柄不肿胀,分棱多,筛孔少而排列不整齐以及只含有巴巴酸等。至于云南的变种stramiuea实际上为一生态型,无分类学意义。浙江的Cetraria aculeata Fr 为聚筛蕊的错误鉴定。根据现有知识,本种分布区的北界在朝鲜为北纬38。,在日本为北纬37。,在中国为北纬31。,而非北纬44。(黑龙江虎林)。     

基于芽苗砧嫁接油茶砧穗创伤后内源激素动态变化分析

为研究油茶(Camellia oleifera A)嫁接时穗条和砧木创伤后内源激素动态变化规律,解析影响砧穗嫁接面愈合的生理机制,为油茶砧穗愈合生长机理提供理论支持。以树龄6年的长林18号和53号的穗条和实生砧木为材料,按照芽苗砧嫁接方法切割穗条S0(0 min)、S10(10 min)、S40(40 min)和砧木茎段Z0(0 min)、Z10(10 min)后,利用液质联用法(HPLC-MS)测定吲哚乙酸(IAA)、脱落酸(ABA)、反式玉米素(TZR)、玉米素(Zeatin)、水杨酸(SA)和茉莉酸(JA)含量,分析不同时间段内源激素变化及品种间差异的关系。结果显示:创伤后18号的TZR、Zeatin和SA含量总体高于53号;18号IAA、SA和JA逐渐下降;TZR和Zeatin分别在S10和S0达最高值后下降;ABA在S10达最高值。53号IAA和JA爱S10达最高值后下降;TZR、Zeatin和SA在S10达低值后逐渐上升;ABA在S0达高值后逐渐下降。砧木茎段创伤前后激素含量除JA外18号高于53号;两品种Z0时激素含量下降,Z10后上升,仅53号ABA和SA含量在Z0达高值后下降。砧木茎段和根部激素含量在品种间除JA外18号高于53号,茎段的IAA、ABA高于根部,其他激素为根部高于茎段。激素比值在品种间和部位间差异明显;IAA/ABA、IAA/TZR、IAA/Zeatin和IAA/JA、ABA/TZR、ABA/Zeatin和ABA/JA比值为53号高于18号;穗条内SA/IAA为18号高于53号,SA/JA和SA/ABA为53号高于18号;砧木茎段均为18号高于53号;TZR/SA、TZR/JA比值在穗条和砧木茎段为18号高于53号。两品种创伤后IAA与JA极显著正相关,而IAA与SA,SA与JA在18号极显著正相关,53号极显著或显著负相关;53号TZR、Zeatin、SA间极显著或显著正相关,JA与TZR、Zeatin和SA极显著负相关。砧木茎段创伤后18号激素间为极显著或显著正相关;53号TZR和Zeatin与IAA、JA极显著正相关,与SA存在显著负相关,SA与JA有显著负相关。砧木茎段和根部间品种间仅在SA与各激素间相关性存在差异,其他激素间存在极显著正相关或负相关。综上所述,砧穗创伤后激素水平上18号在创伤面易于愈伤组织发育,而53号抗逆激素水平较高且与细胞分裂增殖类激素负相关,可能影响53号嫁接后愈合生长;嫁接应在创伤后10 min内较为适宜;砧穗间激素含量及比值的差异可能会影响后期嫁接部位形态重建以及穗条生长。     

社鼠组织器官同工酶的研究

用聚丙烯酰胺凝胶等电聚焦电泳方法,分析了社鼠的肝、肾、心肌、骨骼肌、肺、脾和脑等多种组织器官的ＬＤＨ、ＡＤＨ、ＥＳＴ、和ＳＯＤ４种同工酶,对各组织器官的酶带数目和分布,以及酶活性进行了比较研究。结果表明,社鼠的ＬＤＨ同工酶、ＡＤＨ同工酶和ＥＳＴ同工酶具有比较明显的组织特异性,而ＳＯＤ同工酶的组织特异性较低。肺和脾除ＥＳＴ同工酶活性较高外,脑除ＬＤＨ同工酶活性较高外,其它３种同工酶的活性均较低;而肝和肾中４种同工酶的活性普遍很高。心肌和骨骼肌因氧张力不同而使ＬＤＨ同工酶酶谱存在明显差异,但其它３种同工酶酶谱却非常相似。同工酶的组织特异性与各组织器官所执行的生理功能是相一致的     

洪湖野菰及其化学成分分析

野菰(Zizania latifolia)是湖北省洪湖中优势水生维管束植物,其群落占全湖355平方公里面积的127平方公里。茎和叶的年生物量为4379克鲜重/平方米,全湖总年产量121700吨干重,目前未被利用。野菰各器官的蛋白质和氨基酸含量分别以百分干重表示:根,7.0和4.76;根状茎,11.3和8.85;茎,9.5和7.15;嫩茎梢,22.4和16.53;叶,16.8和14.61。500克干叶的必需氨基酸含量接近100克干重草鱼幼鱼背肌的必需氨基酸含量。脂肪:叶中3.4～4.2,茎中2.2;粗纤维:叶中26.8～28,茎中24.2;灰分:叶中10.0,茎中5.8。菰茎含可溶性糖类30％以上,其中葡萄糖,果糖、蔗糖和麦芽糖是主要成分。结果表明野菰是一种优质饲料。     

Identification of reciprocally regulated gene modules in regenerating dorsal root ganglion neurons and activated peripheral or central nervous system glia

Differential gene expression in the rat after injury of dorsal root ganglion neurons in vivo, and simulation injury of Schwann cells and oligodendrocytes in vitro was analyzed using high-density cDNA microarrays. The analyses were carried out to study the genetic basis of peripheral nerve regeneration, and to compare gene regulation in glia of the central (oligodendrocyte) and peripheral (Schwann cell) nervous systems. The genes showing significant differential regulation in the three study groups represented all aspects of cellular metabolism. However, two unexpected observations were made. Firstly, a number of identical genes were differentially regulated in activated Schwann cells, activated oligodendrocytes and regenerating DRG neurons. Specifically, a group of 113 out of 210 genes that were down-regulated in Schwann cells upon lipopolysaccharide (LPS) treatment, were identical to genes up-regulated in the injured, regenerating DRG. Furthermore, a group of 53 out of 71 genes that were down-regulated in interferon gamma (IFN-gamma)/LPS-activated oligodendrocytes, were identical to genes up-regulated in the DRG neurons. Finally, 22 genes were common to these three groups, i.e., down-regulated in activated oligodendrocytes, down-regulated in activated Schwann cells, and up-regulated in regenerating DRG neurons. Secondly, a group of 16 cell-cycle and proliferation-related genes were up-regulated in the DRG following sciatic nerve crush, despite the absence of cells undergoing mitosis in the DRG, or any significant presence of apoptosis-related gene expression. Therefore, it appears that in these three cell types, large sets of genes are reciprocally regulated upon injury and/or activation. This suggests that the activation of the injury-related gene expression program in cell derivatives of the neuroectoderm involves, in part, highly conserved genetic elements.     

Seasonal patterns in feeding ecology of three small fishes in the Biandantang Lake, China

Feeding ecology of three small fish species, Hypseleotris swinhonis, Ctenogobius giurinus and Pseudorasbora parva was studied seasonally in the Biandantang Lake, a small, shallow lake in central China. Gut length, adjusted for total body length, was significantly higher in spring than in other seasons for all the three species. Seasonal changes in gut length were not associated with changes in food quality. Weight of fore-gut contents, adjusted for body weight, was significantly higher in winter and spring than in summer and autumn in H. swinhonis and C. giurinus , and significantly higher in autumn than in spring and summer for P. parva. Percentage of empty fore-guts was highest in summer and lowest in spring for H. swinhonis and C. giurinus , and highest in winter and lowest in autumn for P. parva. Diet of the three small fishes showed apparent seasonal changes, and these changes reflected partly the seasonal fluctuations of food resources in environment. Diet breadth was high in winter and low in autumn for H. swinhonis , high in winter and low in spring and summer for C. giurinus , and high in autumn and low in spring for P. parva. Diet overlaps between pairs of species were biologically significant in most cases, except between H. swinhonis and P. parva in summer and autumn and between C. giurinus and P. parva in autumn.     

Dynamics of growth and the content of endogenous phytohormones during kidney bean scoto-and photomorphogenesis

The dynamics of growth and the contents of free and bound endogenous IAA, gibberellins (GA), cytokinins (zeatin and its riboside), and ABA in kidney bean plants (Phaseolus vulgaris L., cv. Belozernaya) grown in darkness or in the light was studied. Phytohormones were quantified in 5–15-day-old plants by the ELISA technique. Plant growth and phytohormone content were shown to depend on plant age and the conditions of illumination. During scotomorphogenesis, changes in the biomass and hypocotyl length were highly correlated with the content of GA, whereas during photomorphogeneses, these parameters were correlated with the content of zeatin. In darkness, epicotyl growth displayed a positive correlation with the content of GA, whereas in the light, the correlation was negative. Growth characteristics of the primary leaves were shown to correlate with IAA in darkness and with GA and zeatin in the light. At a low concentration of cytokinins in illuminated leaves, cell divisions occurred, whereas, at the higher cytokinin concentrations, cell expansion occurred. The highest content of GA was characteristic of leaves in the period of growth cessation. ABA accumulated during active leaf and root elongation and biomass increment in the light and during hypocotyl growth in darkness. After plant illumination, the ratio of auxins to cytokinins increased in bean roots and decreased in their epicotyls. Thus, light changed the developmental programs of bean plants, which was manifested in the changed rate and duration of growth of various organs (root, hypocotyl, epicotyl, and leaf). Some mechanisms of light action depended on the contents of IAA, ABA, GA, and cytokinins and the ratios between these phytohormones. Differences between scotonorphogenesis of mono-and dicotyledonous plants are discussed in relation to the levels of phytohormones in them.     

啮齿动物作用下退耕地山杏种子扩散与贮藏的季节变化

啮齿动物对植物种子的取食和扩散影响种子的时空分布,继而影响种子的萌发和幼苗建成,因而在森林更新中起着重要作用.在国有济源市愚公林场,选择退耕地生境,于春季、夏季、秋季分别释放人工标记的山杏种子,观察啮齿动物扩散与埋藏山杏种子的季节性差异.结果表明：1）退耕地中的啮齿动物主要包括大林姬鼠、社鼠、黑线姬鼠;2）山杏种子扩散速率在春季显著慢于夏季,夏季显著慢于秋季;3）种子搬运量受季节和种子状态交互作用影响,春季显著少于夏季,夏季显著少于秋季;4）不同季节种子平均搬运距离不同,秋季不同状态种子的搬运距离均大于春季和夏季;5）啮齿动物对山杏种子的贮藏点大小多为1粒种子,少量为2、3粒种子,且贮藏点大小与季节间存在显著的交互作用,春季单粒种子的贮藏点数量显著少于夏季和秋季,而夏季与秋季的贮藏点则倾向于多粒种子;6）在夏季和秋季各有5枚（共释放1800枚）被啮齿动物分散贮藏的山杏种子建成幼苗.     

Regulation of the catalytic activity of preexisting tyrosinase in black and Caucasian human melanocyte cell cultures

The activity of tyrosinase, the rate-limiting enzyme for melanin synthesis, is higher in Black skin melanocytes than in melanocytes derived from Caucasian skin. This variation in enzyme activity is not due to differences in tyrosinase abundance or tyrosinase gene activity, but, rather, is due to differences in the catalytic activity of preexisting tyrosinase. In melanocytes, tyrosinase is localized to the membrane of melanosomes and in Caucasian melanocytes the melanosome-bound enzyme is largely inactive. Conversely, in melanosomes of Black melanocytes, tyrosinase has high catalytic activity. Treatment of Caucasian melanocytes with the lysosomotropic compound ammonium chloride or with the ionophores nigericin and monensin results in a rapid and pronounced increase in tyrosinase activity. This increase occurs without any change in tyrosinase abundance, indicating that these compounds are increasing the catalytic activity of preexisting enzyme. Inhibition of the vacuolar proton pump V-ATPase by treatment of Caucasian melanocytes with bafilomycin also increases tyrosinase activity. In contrast to the 10-fold increase in tyrosinase observed in Caucasian melanocytes, neither ammonium chloride, monensin, nigericin, nor bafilomycin is able to increase the already high level of tyrosinase activity present in melanosomes of melanocytes derived from Black skin. Finally, staining of Caucasian melanocytes with the fluorescent weak base acridine orange shows that melanosomes of Caucasian, but not Black, melanocytes are acidic organelles. These data support a model for racial pigmentation that is based on differences in melanosome pH in Black and Caucasian skin types. The models suggests that melanosomes of Caucasian melanocytes are acidic, while those of Black individuals are more neutral. Since tyrosinase is inactive in an acid environment, the enzyme is largely inactive in Caucasian melanosomes but fully active in Black melanosomes.     

安蕨属的分类与分布

1849年,捷克人Presl根据菲律宾产的一种蕨类植物Anisocampium cumingia-num Presl,建立了安蕨属Anisocapium Presl,几十年来未被各国植物学家(如Baker、Beddom、Makino、C.Christensen、Christ、Nakai、秦仁昌、Devol、Ohwi和Tagawa)所承认。1940年,Tard.-Blot et C.Chr.编写《印度支那植物通志》(Fl.Gen.Indo-Chine)时接受了安蕨属的概念。1947年,美国人Copeland研究东南亚蕨类植物时,也肯定了安蕨属是一个自然分类群。以后,     

Differential distribution of leaf chemistry in eucalypt seedlings due to variation in whole-plant nutrient availability

We investigated the effects of whole-plant nutrient-availability on the degree of distribution of some plant primary and secondary (nitrogen, fibre, flavonols, gallotannins and cineole) chemicals across young, mature and old leaves of seedlings of Eucalyptus nitens. Four treatments that ranged from low to high nutrient-application rates resulted in mean whole-plant foliar concentrations of 0.63%, 0.85%, 1.11% and 1.82% nitrogen dry matter (N%DM) for treatments A, B, C and D, respectively. Within-plant distribution (across the leaf age profile of young, mature and old leaves within a eucalypt seedling) of N%DM ranged from zero in treatment A to a wide range of distribution in treatment D (low N%DM concentrations in old leaves to high N%DM concentrations in young leaves). Similarly, the distribution of fibre ranged from zero in treatment A to a wide range of distribution in treatment D, but with high concentrations in old leaves and low concentrations in young leaves. In contrast, flavonols (weakly) and gallotannins had a wide range of distribution in treatment A (low concentrations in old leaves to high concentrations in young leaves) but were little or not distributed in the other treatments. Again in contrast, cineole was strongly distributed between old and young leaves (low concentrations in old leaves to high concentrations in young leaves) across all treatments while concentrations in mature leaves reflected one or other leaf age depending on treatment. Protein precipitable phenols in treatments A, B and C were high in young, and low in old leaves; whereas in treatment D they were low and similar between leaves of different ages.