分批异养培养小球藻光密度值与干重的关系*

在小球藻的分批异养培养过程中,培养液的细胞浊度（ＯＤ）与细胞干重（ＤＷ）的关系受培养条件和培养过程的影响很大,在实验中,干重与光密度值的比值在０．５３～０．２８ｇ／ＯＤ·Ｌ间变化。因此在小球藻分批异养培养过程中,培养液藻生物量检测采用单一的ＤＷ与ＯＤ换算常数用ＯＤ来推算细胞的干重则会产生较大的误差。     

小球藻的异养培养及应用前景

介绍了小球藻异养培养的营养需求,条件控制以及应用前景。     

植物激素IBA与6-BA对摇瓶分批流加异养培养小球藻的生长及化学组成的影响

研究了植物激素IBA与6-BA对摇瓶分批流加异养培养小球藻的生长及化学组成的影响。结果表明,IBA与6-BA处理摇瓶分批流加异养培养的小球藻,促进了小球藻的生长,提高了小球藻的生物量(15．0％)与对糖转化率(14．8％),同时也提高了小球藻的蛋白质含量(16．3％)。氨基酸分析结果表明,IBA与6-BA能提高摇瓶分批流加异养培养的小球藻的α-氨基酸含量(含量达31．2％,而对照的仅26．0％),增加必需氨基酸的含量及比例,尤其两种重要α-氨基酸Arg和Lys的含量分别提高达22．9％和30．1％,强化了异养小球藻的营养价值。IBA与6-BA能提高摇瓶分批流加异养培养的小球藻叶绿素及类胡萝卜素含量。培养工艺研究与化学组成分析将为植物激素应用于小球藻的异养培养奠定基础。     

植物激素在小球藻异养培养中的作用

本文研究了几种植物激素对小球藻异养培养的影响。结果表明,IAA、IBA及6-BA三种植物激素均不同程度地促进了小球藻的异养生长,培养≤36h时,IAA或IBA以20mg／L的促进小球藻异养生长的效应最大,100mg／L IAA或IBA则抑制了藻的生长;>36h时,100mg／L IAA或IBA表现出促进小球藻生长的效应,并最终获最大净A540增长量;6-BA以0.1 mg／L的促进作用最大。IBA与6-BA组合同样表现出促进小球藻异养生长的效应,但并非IBA和6-BA简单的加合效应,5 mg／LIBA与6-BA组合的效应维持6-BA单因子的作用趋势,20mg／LIBA与lmg/L6-BA组合的效应大于与0.1mg／L6-BA组合的,100mg／LIBA与0.1mg／L6-BA组合的效应在≤36h时大于与1mg／L6-BA组合的,>36h时则相反。另外,高浓度IBA(≥20mg／L)与6-BA组合抑制了前中期异养藻对葡萄糖的吸收,但加速了中后期葡萄的吸收。再者,IBA与6-BA组合加速了异养小球藻对No-3的吸收。     

植物激素在小球藻异养培养中的作用

本文研究了几种植物激素对小球藻异养培养的影响。结果表明 ,IAA、IBA及 6_BA三种植物激素均不同程度地促进了小球藻的异养生长 ,培养≤ 36h时 ,IAA或IBA以 2 0mg/L的促进小球藻异养生长的效应最大 ,1 0 0mg/LIAA或IBA则抑制了藻的生长 ;>36h时 ,1 0 0mg/LIAA或IBA表现出促进小球藻生长的效应 ,并最终获最大净A540 增长量 ;6_BA以 0 1mg/L的促进作用最大。IBA与 6_BA组合同样表现出促进小球藻异养生长的效应 ,但并非IBA和 6_BA简单的加合效应 ,5mg/LIBA与 6_BA组合的效应维持 6_BA单因子的作用趋势 ,2 0mg/LIBA与 1mg/L 6_BA组合的效应大于与 0 .1mg/L 6_BA组合的 ,1 0 0mg/LIBA与 0 .1mg/L 6_BA组合的效应在≤ 36h时大于与 1mg/L 6_BA组合的 ,>36h时则相反。另外 ,高浓度IBA(≥ 2 0mg/L)与 6_BA组合抑制了前中期异养藻对葡萄糖的吸收 ,但加速了中后期葡萄的吸收。再者 ,IBA与 6_BA组合加速了异养小球藻对NO_3 的吸收。     

谷氨酸对异养培养小球藻生长的影响

在不添加其他氮源的小球藻异养培养基中,谷氨酸可促进小球藻的生长,但基本不增加叶绿素的合成;在以铵盐为氮源时,谷氨酸可明显促进小球藻对铵盐的利用,促进小球藻生物量增加和叶绿素合成;在以硝酸盐为氮源时,谷氨酸可增加小球藻的生物量,对叶绿素含量无明显影响。     

利用啤酒废水小球藻异养培养

摘要：【目的】利用小球藻异养培养技术处理啤酒废水,旨在为啤酒废水资源化利用和降低小球藻生产成本提供一个途径。【方法】在含有10 g/L葡萄糖的基本培养基进行异养小球藻高效藻株的筛选,并用于啤酒废水的资源化处理。【结果】从5株小球藻中得到2株适合高密度异养培养的藻株（Chlorella pyrenoidosa 15-2070 和 Chlorella vulgaris 15-2075）,在啤酒废水的资源化处理过程中这2株小球藻得到非常接近的试验结果。利用由废水配制含10 g/L葡萄糖的基本培养液培养Chlorella pyrenoidosa 15-2070获得了5.3 g/L藻细胞;并且在此过程中,啤酒废水得到有效利用,几种主要污染物最高去除率为：CODcr,92.2 %;BOD5,95.1 %;NO3--N,98.5 %;NH4+-N,92.3 %。【结论】啤酒废水中的重要环境污染物在培养小球藻的过程中可以得到有效地清除,并从中可以获得具有商业价值的小球藻细胞。     

小球藻细胞的异养转化

总结了异养转化后小球藻细胞在结构、生物化学成分和可能的代谢机制方面的研究进展,并对其应用潜力提出了初步看法。     

小球藻的异养生长及培养条件优化

对小球藻异养培养中的碳源、氮源、微量元素—镁离子以及其他培养条件的影响进行了探讨 ,并测定了小球藻的生长曲线。优化结果 :C∶ N为 4∶ 1～ 5∶ 1 ,硫酸镁的量为 1 g/L;培养条件为 :p H6～ 7,接种量1 0 % ,温度 3 0°C。在此条件下 ,异养培养小球藻 ,其 OD值可达 1 8,蛋白质为 3 0 % ,叶绿素含量为 1 .2 %。     

自养与异养小球藻脂溶性化合物对比研究

应用细胞培养技术获绿色自养小球藻与乳黄色异养小球藻细胞。异养藻细胞脂溶性化合物占细胞干重的７２％,是自养藻的４倍多。两类细胞烃类化合物的分布特征发生了显变化,自养藻以正十七烷占绝对优势;异养藻富含长链正烷烃,以正二十五烷烃占优势。两类细胞脂溶性色素化合物和苯洗脱组分化合物以及Ｃ、Ｈ、Ｏ、Ｎ１４种有机元素相对含量也差异显。对比实验结果对于异养小球藻的代谢研究和油脂化合物的开发利用具有重要意义。     

普通小球藻生长与武汉东湖水体磷形态的相关研究

本文探讨了武汉东湖水体中总溶解磷（TSP）、溶解反应磷（SRP）、总反应磷（TRP）、溶解水解磷（SHP）和颗粒磷（PP）对普通小球藻生长的生物有效利用性。进行了普通小球藻生长量与各磷形态及总磷（TP）被利用浓度的一元相关分析,进一步讨论了这些一元相关方程的不足,并用多元回归分析建立了普通小球藻生长量（N）与所测几种磷形态被利用浓度（CTSP,CSRP,CTRP,CSHP,CPP）的相关模型。这些模型可以用于评价湖泊水体富营养化的程度及预测藻的生长潜力。     

ORGANIC CARBON SUPPLEMENTATION OF STERILIZED MUNICIPAL WASTEWATER IS ESSENTIAL FOR HETEROTROPHIC GROWTH AND REMOVING AMMONIUM BY THE MICROALGA CHLORELLA VULGARIS1

Heterotrophic growth of the microalga Chlorella vulgaris Beij. in synthetic as well as sterilized municipal wastewater of a nonindustrialized city was measured. The city wastewater contained high levels of ammonium and nitrate, medium levels of phosphate, and low levels of nitrite and organic molecules and could not support heterotrophic growth of C. vulgaris. Evaluation of 11 known carbon sources for this microalga that were added to standard synthetic wastewater containing the same levels of nitrogen and phosphorus as the municipal wastewater revealed that the best carbon sources for heterotrophic growth were Na‐acetate and d ‐glucose. These provided the highest growth rates and the largest removal of ammonium. Growth increased with concentration of the supplement to an optimum at 0.12 M Na‐acetate. This carbon source was consumed completely within 10 d of incubation. Higher concentrations inhibited the growth of C. vulgaris. The microalgal populations under heterotrophic growth conditions were one level of magnitude higher than that under autotrophic growth conditions that served as a comparison. No growth occurred in the dark in the absence of a carbon source. Na‐acetate was superior to d ‐glucose. In municipal wastewater, when Na‐acetate or d ‐glucose was added, C. vulgaris significantly enhanced ammonium removal under heterotrophic conditions, and its capacity was equal to ammonium removal under autotrophic growth conditions. This study showed that sterilized wastewater can be treated by C. vulgaris under heterotrophic conditions if supplemented with the appropriate organic carbon source for the microalgae.     

小球藻细胞壁缺陷型突变体的筛选及转化系统的建立

由于高效、稳定遗传转化系统的缺乏,小球藻遗传改良以及油脂代谢机理的研究等工作难以进行。研究旨在通过筛选获得小球藻Chlorella vulgaris细胞壁缺陷型突变体,在此基础上建立其转化系统。首先通过紫外诱变获得小球藻Chlorella vulgaris的突变体库,基于细胞壁缺陷型突变体在1% Triton X-100处理后叶绿素会释放到上清中的原理,利用酶标仪高通量地从约4000个突变体中筛选获得10株细胞壁缺陷的小球藻。同时以小球藻内源性-tubulin的启动子和终止子作为启动子和终止子,以AphⅧ (Aminoglycoside 3'-Phosphotransferase type Ⅷ)作为报告基因构建了转化载体pHK203。通过优化电转缓冲液组分和电击参数,确定了细胞壁缺陷型突变体CWD-3的最佳转化条件,即2 g pHK203,ddH2O作为电转缓冲液,1500 V,525 ,50 F的电击条件下,转化效率可达到40个转化子/g DNA。研究为小球藻Chlorella vulgaris的油脂代谢通路和遗传改良提供了技术基础,同时由于可降低破壁成本,筛选获得的细胞壁缺陷型突变体适于工业化生产小球藻藻粉。     

小球藻LEA 家族蛋白Ccor1和Ccor2在抗盐胁迫中的作用

LEA蛋白是与植物抗逆反应相关的一类重要蛋白质,可以在发育的植物胚胎、处于干旱、寒冷、盐胁迫的植物组织中高水平表达。LEA蛋白最早发现于棉花子叶中,随后也在其他高等植物、藻类、真菌、蓝藻以及线虫中被发现。LEA蛋白代表一个庞大的基因家族,早期是根据     

生物异源物质对小球藻基因转录研究体系的建立(英文)

藻类是水生生态系统中的敏感物种。在环境生物学研究中,基因转录水平通常作为衡量基因表达水平变化的指标。研究建立了定量PCR技术(Real-time PCR)检测小球藻基因转录变化的研究体系。以3个主要光合作用基因(psaB、psbC、rbcL)为靶标基因,研究了除草剂草丁瞵(Glufosinate)、阿特拉津(Atrazine)和禾草灵(Diclofop-methyl)对基因转录的影响,结果表明3种供试药物对小球藻光合作用基因psbC和rbcL相对表达量有显著地抑制作用。这表明Real-time PCR可以作为评定水生环境中异源化合物毒性的有效方法。     

DISTINCTION BETWEEN MULTIPLE ISOLATES OF CHLORELLA VULGARIS (CHLOROPHYTA,TREBOUXIOPHYCEAE) AND TESTING FOR CONSPECIFICITY USING AMPLIFIED FRAGMENT LENGTH POLYMORPHISM AND ITS RDNA SEQUENCES1

Multiple strains of individual algal species are available from public culture collections, often with the same isolate being maintained in parallel at a number of collections under different culture regimes. To unravel genomic variation and to identify unique genotypes among such multiple strains, two approaches were used on a sample of 29 strains of Chlorella vulgaris Beijerinck, an alga of great value for applied research, from five culture collections. With the exception of two strains, internal transcribed spacer rDNA sequence data substantiated conspecificity of the studied strains and only minor sequence differences with the authentic “Beijerinck isolate” were observed. Amplified fragment length polymorphism (AFLP) detected considerable genomic variation when rDNA sequences were identical. Band detection and the construction of a binary matrix from AFLP patterns for phylogenetic analyses were fully automated, but comparison of similar patterns still required manual refinement. The AFLPs distinguished 11 unique genotypes and provided robust support for the presence of five cryptic species. This finding advocates the need to carefully record which strain has been used in any experiment or in applied research, because genomic variation may also correspond to differences in physiological/biochemical properties. No genomic differences could be detected between duplicate strains of the same isolate that were maintained by continuous subculturing over many decades or within those stored at ultralow temperatures.     

趋磁细菌WD—1的超微结构及批量培养方法

报道了趋磁细菌WD－1的超微结构,菌株WD－1的超薄切片清楚地显示了细胞壁（CW）、细胞膜（CM）、细胞内部的聚β－羟基丁酸（poly-β-hydroxybutyrate）和磁小体（Magnetosomes MS)。建立了菌体和磁小体批量培养和收集的方法,经培养每升培养基可获得135mg干菌体。经SEM能谱分析菌体和磁小都含有Fe、AI、Si、P、S、Ca、Zn等元素组分;菌体和磁小体中铁的含量分别为3．07％和84．57％。     

翼手目物种密度分布与环境因素的关系

本文通过划分小区和运用相关分析法,分析了翼手目|物种密度分布与主要环境因素的关系。在海拔2000米以上地区物种密度明显减少,海拔4000米以上则非常贫乏,其物种数还随纬度升高而递减。物种密度分布与年均温呈正相关关系,与相对湿度呈半对数线性关系,与日照时数呈负相关关系。但翼手目物种密度最高处并不是温湿度最高地区,而是在碳酸盐岩发达的有丰富山洞地貌的低山丘陵地区。     

COMPARATIVE PHYSIOLOGY AND BIOCHEMISTRY AND TAXONOMIC ASSIGNMENT OF THE CHLORELLA (CHLOROPHYCEAE) STRAINS OF THE CULTURE COLLECTION OF THE UNIVERSITY OF TEXAS AT AUSTIN1

The species of the genus Chlorella exhibit considerable biochemical and physiological differences. Therefore, it is important to select for and utilize in research or biotechnology correctly identified strains of the species having the most favorable properties for the respective project. We examined the Chlorella strains of the University of Texas collection at Austin, Texas, according to species-specific chemotaxonomic characters and assigned 58 strains to 10 well-established species (only 17 of these strains were correctly named before).     

EFFECTS OF SEEDING DENSITY AND BASIC MANURE ON THE GROWTH OF DRY NURSERY SEEDLINGS IN LATE DOUBLE CROPPING RICE IN SOUTH CHINA

During the period of dry nursery seedling raising of late double cropping indica rice in South China, both chemical fertilizer and farmyard manure did not show obvious effect on the growth of shoot and root in young seedlings at 4-leaf stage (18-day-old seedling), but had significant effects on root growth in old seedlings with 6-7 leaves (27-day-old seedling) at suitable seeding densities (65-125g m~(-2)). There were satistically significant differences (at 0.01 or 0.05 levels)between treatments in root number and rooting ability of root-pruned seedlings.