Chrysochromulina tenuispina sp. nov. from arctic Canada

Chrysochromulina tenuispina sp. nov., has been described with the aid of light microscopy, scanning electron microscopy and transmission electron microscopy on dry preparations set up in situ from very cold water (-1°C) at one locality in arctic Canada. The cells are exceptionally large, with a highly characteristic periplast dominated by circular or oval plate-scales, some carrying a centrally attached stiff, slender, spine, up to 3 µm long and not more than 0·1 µm thick, indistinctly twisted through approximately two and a half turns from base to tip and underlain by larger more oval plates without spines. The patterning on the two faces of both types of plate is described in sufficient detail to demonstrate the presence of two sublayers building up the structure of each scale-face, the four superposed sublayers of a complete scale being interconnected in various ways.     

Characterization of a non-thermophilic strain of the red algal genus Galdieria isolated from Soos (Czech Republic)

Volcanic areas with highly acidic solfatara soils and temperatures of up to 56?°C are inhabited by the red algal genus Galdieria. We examined three highly acidic but non-volcanic habitats in the western part of the Czech Republic for the occurrence of this red alga. In soil samples from the National Nature Reserve of Soos we found, together with Euglena mutabilis, Pseudococcomyxa simplex and species of Chlorella, a new strain of Galdieria. In contrast to all other Galdieria strains described so far, the strain from Soos exhibited a low temperature optimum for growth of about 30?°C. Other properties, such as the substrate spectrum for heterotrophic growth, ultrastructure, fatty acid composition, thermostability of enzymes and the nitrogen source, showed no obvious differences from other strains of Galdieria. Within a phylogenetic tree based on 18S rRNA sequence data, the strain from Soos occupied a position at the base of the ‘Galdieria’-branch. Our findings indicate that the genus Galdieria is not restricted to volcanic and mining areas and that strains of Galdieria are able to compete successfully with green algae in habitats like Soos.     

The effect of nitrogen starvation on the ultrastructure and pigment composition of chloroplasts in the acidothermophilic microalga Galdieria sulphuraria

We studied the effect of nitrogen starvation on growth indices, vitality, ultrastructure, and the photosynthetic apparatus of unique acidothermophilic microalga Galdieria sulphuraria (Galdieri) Merola. Long-term nitrogen starvation ceased G. sulphuraria growth and cell division. During the first days of starvation, phycobiliproteins degraded first, then the content of chlorophyll and carotenoids decreased to trace amounts, chloroplast reduced, cell wall became thinner, and storage compounds accumulated. However, the cells were alive. A comparison with the effects of nitrogen starvation on other photosynthesizing organisms showed that suppression of cell division, reduction of the photosynthetic apparatus to some minimum, and accumulation of storage compounds are a universal response to this stress.     

Purification and characterization of UDP-D-galactose 4-epimerase from the red alga Galdieria sulphuraria

UDP-D-galactose 4-epimerase of the unicellular red alga Galdieria sulphuraria has been purified to apparent electrophoretic homogeneity by chromatography on DEAE-Fractogel, hydroxylapatite and by affinity chromatography on Dyematrex Orange. The holoenzyme is a homodimer with an apparent molecular mass of 83 and 76 kDa as determined by gelfiltration and by sucrose gradient centrifugation, respectively. The size of the subunits was 42 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The 4-epimerase from G. sulphuraria does not require external NAD for activity, unlike the enzyme from some other organisms, and inhibition by NADH was not observed. The apparent K_m for UDP-D-galactose was 64 μ M . The pH optimum was at 8 and the apparent equilibrium constant for UDP-Glc/UDP-Gal was 3.5. The enzyme in crude as well as in purified samples was unusually stable and was not inactivated even on incubation at 46°C for several hours.     

Stable Form of Ascorbate Peroxidase from the Red Alga Galdieria partita Similar to Both Chloroplastic and Cytosolic Isoforms of Higher Plants

Depletion of the electron donor ascorbate causes rapid inactivation of chloroplastic ascorbate peroxidase (APX) of higher plants, while cytosolic APX is stable under such conditions. Here we report the cloning of cDNA from Galdieria partita, a unicellular red alga, encoding a novel type of APX (APX-B). The electrophoretic mobility, K _m values, k _cat and absorption spectra of recombinant APX-B produced in Escherichia coli were measured. Recombinant APX-B remained active for at least 180 min after depletion of ascorbate. The amino-terminal half of APX-B, which forms the distal pocket of the active site, was richer in amino acid residues conserved in chloroplastic APXs of higher plants rather than cytosolic APXs. In contrast, the sequence of the carboxyl-terminal half, which forms the proximal pocket, was similar to that of the cytosolic isoform. The stability of APX-B might be due to its cytosolic isoform-like structure of the carboxyl-terminal half.     

红藻条斑紫菜R-藻红蛋白晶体的时间分辨偏振荧光研究

本文在皮秒时域内研究红藻条斑紫菜Ｒ－藻红蛋白单晶在不同晶轴取向下的偏振荧光动力学过程。荧光衰减表现为二指数过程,即与色素之间的能量传递和激发平衡有关的快过程（τ１≤６０ｐｓ）和色素荧光跃迁过程（τ２～３００ｐｓ）;由于色素间的能量传递,荧光明显退偏振;由于晶体中色素的光学跃迁矩取向倾向于沿主晶轴方向分布,在不同的晶轴的取向下各向异性荧光衰减过程明显不同。     

海洋红藻和蓝藻中的别藻蓝蛋白结构特征的比较

红毛菜、坛紫菜和条斑紫菜三种海洋红藻中的别藻蓝蛋白的特征吸收光谱(λ_(max)650 nm),荧光发射光谱(F_(max)662nm)、等电点(pI 4.42)、聚集态(分子量:134 kD)及其亚基分子量(α17kD,β18.5kD)均相同;结合它们各自吸收光谱的二阶导数光谱、圆二色谱和氨基酸残基组成等,与蓝藻--螺旋藻中的别藻蓝蛋白进行了比较。研究结果表明:四种来源不同的别藻蓝蛋白结构具有同一性,都是由α和β两个亚基组成的(αβ)_3结构。     

Isethionic Acid and Floridoside Isolated from the Red Alga,Grateloupia turuturu,Inhibit Settlement of Balanus amphitrite Cyprid Larvae

Isethionic acid (2-hydroxyethane sulfonic acid) and floridoside (2-O-α-D-galactopyranosylglycerol) were extracted from the red alga, Grateloupia turuturu, and tested for anti-settlement activity against cyprid larvae of the tropical barnacle, Balanus amphitrite and for their toxicity to nauplius larvae. Isethionic acid was active for anti-settlement but had the disadvantage of being toxic to nauplius larvae. Floridoside was a potent inhibitor of cyprid settlement at non-toxic concentrations to nauplii (0.01 mg ml^?1).     

Studies on Triterpenoid Constituents Isolated from the Roots of Sabia schumanniana

Five triterpenoids were isolated from the roots of Sabia schurnanniana Diels. Based on their physical constants, UV. IR, 1H-NMR, 13C-NMR, DEPT spectroscopic analysis and preparation of their derivatives, they were identified as 3-oxo-olean-ll, 13 (18)-diene (1), 3, 1 1-dioxo-olean- 12-ene (2), 3β -hydroxy-olean- 11, 13 (1 8) -diene (3), 3-oxo, 11 α-hydroxy-olean-12-ene (4), 3, 11α-dihydroxy-olean-12-ene (5) . Compound 4 is a new compound. Their 13C-NMR spectra have been signified by means of DEPT analysis.     

海洋赤潮生物与厦门海域几种细菌的生态关系研究

选择我国沿海易发有毒赤潮藻——塔马亚历山大藻 [Alexandrium tamarense (Lebour) Balech,1 985 ]和从厦门海域筛选的海洋细菌作为实验材料 ,研究在实验生态条件下 A.tamarense的生理生态特征 ,及其与 3株从厦门海域筛选的海洋细菌 S5,S7,S10 与 A.tamarense共同培养表现的生态关系的差异性。结果表明 :在实验室条件下 ,A.tamarense可以较好地生长并保持自然状态下的若干特性 ,其生长曲线与微型生物的生长曲线相似 ;分别在藻细胞生长的延滞期和指数期加入细菌过滤液 ,发现 3种海洋细菌的过滤液对 A.tamarense生长有不同的抑制作用效果。三者的抑藻能力大小依次为 S10 >S5>S7。本文对海洋细菌抑藻作用机理、赤潮的生物防治可能性进行了讨论。     

Effects of Environmental Factors and Metal Ions on Growth of the Red Alga Gracilaria Chorda Holmes (Gracilariales, Rhodophyta)

Gracilaria is a potentially valuable source of marine biopolymers such as proteins and polysaccharides. In order to select suitable culture conditions, growth and tolerance of Gracilaria chorda Holmes from Shikoku Island in southwest Japan were investigated under variations of temperature (5–30 ^∘C), photon irradiance (20–120 μmol photons m⁻² s⁻¹), and photoperiod (12:12 h, 14:10 h light:dark regime) in a unialgal culture. Gracilaria chorda showed wide tolerances for all factors investigated, which is characteristic of eurythermal species. Maximum growth was observed at 18–24 ^∘C. The optimum photon irradiance for the algal growth was 60–120 μmol photons m⁻²s⁻¹. Instead of using ordinary sea salt (NaCl) to prepare artificial seawater, ultra pure salt was adopted. Gracilaria chorda grew faster in artificial seawater made with ultra-pure salt than that made with ordinary sea salt, probably because the former medium was clear, while the latter was milky. Effects of some metal ions on the growth were tested with artificial seawater. Iron ions affected algal growth, but cobalt ions did not. This study enables us to determine suitable culture conditions for G. chorda. A scaled-up 30 l culture of G. chorda under such conditions was successful.     

人粪便中分离的噬菌蛭弧菌生物学特性的研究

本文研究了人粪便中分离的噬菌蛭弧菌的生物学特性,测定了它们的生长曲线,并利用微孔滤膜过滤和机械振荡的方法,研究了它们的吸附和穿入动力学,发现链霉素、庆大霉素和卡那霉素能抑制蛭弧菌的吸附;青霉素不影响蛭弧菌的吸附和穿入,但抑制蛭弧菌在宿主内的生长过程。从人粪中分出的噬菌蛭弧菌不仅能裂解大部分需氧的革兰氏阴性菌,而且在微氧条件下也能裂解厌氧菌中的二株脆弱拟杆菌。我们发现一株人粪便中分出的噬菌蛭弧菌能形成蛭弧菌囊体——它的休眠态,它对高热、紫外线照射和真空干燥的耐受力较相应的繁殖体强,看来它是蛭弧菌保持生命期限的一种方式。     

中国西南地区水龙骨属植物(水龙骨科)孢子形态研究

利用光学显微镜和扫描电子显微镜对水龙骨属(PolypodiodesCh ing)植物11种(包括1变种)的孢子进行了观察和比较研究。其中,大部分种为首次报道。水龙骨属植物的孢子单裂缝,两侧对称,极面观椭圆形,赤道面观豆形或超半圆形,表面具疣状纹饰,多不具周壁。对光茎水龙骨(P.wattii)和日本水龙骨(P.niponica)、栗柄水龙骨(P.m icrorhizoma)与篦齿蕨(M etapolypodium manm eiense)亲缘关系进行了讨论,为该属植物的系统分类提供了孢粉学方面的证据。根据水龙骨属植物孢粉形态上的证据,水龙骨属植物是一个自然的分类群,赞成秦仁昌1978分类系统的分类处理。     

豆科植物中鱼藤酮含量测定及光学异构体研究

采用HPLC法测定了豆科鱼藤属的毛鱼藤、白花鱼藤、边荚鱼藤、马来鱼藤,灰豆属的非洲山毛豆、灰毛豆,豆薯属的豆薯、鸡血藤属厚果鸡血藤和紫穗槐属紫穗槐9种植物中鱼藤酮含量,发现毛鱼藤含量最高,每100g植物干粉中含1．82g鱼藤酮,紫穗槐含量最低,仅含0．005g。通过比较毛鱼藤、白花鱼藤、边荚鱼藤、非洲山毛豆、豆薯分离得到鱼藤酮的比旋光度,结合马来鱼藤、灰毛豆、厚果鸡血藤、紫穗槐提取物对3龄家蚕的点滴触杀活性差异,说明这些植物中含有的鱼藤酮均为同-光学异构体。     

一株印楝植物内生真菌Epicoccumsp．次生代谢产物的研究

从印楝植物内生真菌Epicoccum sp.的发酵液中分离得到6个化合物,经波谱数据分析分别鉴定为苔黑酚(1)、4-甲基苔黑酚(2)、苔色酸(3)、对羟基苯乙酸(4)、邻苯二甲酸正丁异丁酯(5)、乙基-β-D-葡萄糖苷(6).以上化合物均为首次从该属真菌中分离得到.     

油菜菌核病菌对速克灵的抗药性风险研究

在室内条件下通过菌丝生长速率法测定了分离自安徽省10个县市的油菜菌核病菌（Sclerotinia scleroti-orum）对速克灵的敏感性。结果表明,速克灵对各供试菌株的EC50值分布范围为0.0899-0.4966μg/mL,平均为0.2541μg/mL,且供试菌株在含速克灵质量浓度为10 000μg/mL的PDA平板上菌丝生长几乎完全被抑制。表明各供试菌株对速克灵十分敏感,但其敏感程度地区间存在较大差异。通过室内药剂直接诱变法,获得了抗速克灵突变株。抗性突变株抗性测定结果表明,某些地区的抗性菌株抗性消失,有些地区的抗性菌株抗性继续保持。结果显示安徽省油菜菌核病菌对速克灵具有潜在的抗药性风险。     

The Effect of Hydrogen Peroxide on the Growth of Microscopic Mycelial Fungi Isolated from Habitats with Different Levels of Radioactive Contamination

The effect of hydrogen peroxide (10^?9–10^?1 M) on the mycelial growth of the fungi Alternaria alternata, Cladosporium cladosporioides, Mucor hiemalis, and Paecilomyces lilacinus has been studied. The growth of fungi isolated from habitats with a background level of radioactive contamination was stopped by H₂O₂ concentrations equal to 10^?3 and 10^?2 M, whereas the growth of fungi that were isolated from habitats with high levels of radioactive contamination was only arrested by 10^?1 M H₂O₂. The response of the different fungi to hydrogen peroxide was of three types: (1) a constant growth rate of fungal hyphae at H₂O₂ concentrations between 10^?9 and 10^?4 M and a decrease in this rate at 10^?3 M H₂O₂, (2) a gradual decrease in the growth rate as the H₂O₂ concentration was increased, and (3) an increase in the growth rate as the H₂O₂ concentration was increased from 10^?6 to 10^?5 M. The melanin-containing species A. alternata and C. cladosporioides exhibited all three types of growth response to hydrogen peroxide, whereas the light-pigmented species M. hiemalis and P. lilacinus showed only the first type of growth response. A concentration of hydrogen peroxide equal to 10^?1 M was found to be lethal to all of the fungi studied. The most resistant to hydrogen peroxide was found to be the strain A. alternata 56, isolated from the exclusion zone of the Chernobyl Nuclear Power Plant.     

Studies on the chemical composition and biological activity of essential oil from Cyperus rotundus Linn.

The sesquiterpene caryophyllene in its alcohol form has been identified for the first time from the essential oil of the tubers of Cyperus rotundus Linn. The structure of the alcohol has been identified by spectroscopic and chemical methods. Bioefficacy of the oil and its hydrocarbon, ketonic and alcoholic fractions is reported for maize and mungbean.     

离子注入哈茨木霉筛选高产促植物生长物质菌株的研究

用 N+注入哈茨木霉所获得的突变型的发酵液浇灌水稻种子 ,结果发现 :5× 10 - 6、5× 10 - 5、2× 10 - 4木霉突变株发酵稀释液处理的种子幼苗长势优于对照组和木霉原种组。其 5 0倍、15 0倍木霉发酵稀释液浇灌的种子幼苗过氧化物酶同工酶与对照和原种相比均出现了新的谱带 A- 3、C- 3带。各突变株 5 0倍发酵稀释液和原种发酵液浇灌的水稻幼苗过氧化物酶同工酶出现了 B- 3带。而四种浓度的木霉发酵稀释液处理的水稻幼苗 ,其酯酶同工酶与对照组和原种组相比 ,无明显差异