取代芳烃对月芽藻、大鼠等毒性的构效关系研究

提出了新的原子生物活性值(αi)并由其建构自相关拓扑指数(^mL)．^oL和L分别与取代芳烃对月芽藻、发光菌慢性毒性关联，其相关系数分别为0．9315和0．9439；对酵母菌、发光菌、大鼠的急性毒性的相关系数依次为0．9482，0．9064和0．9762．     

利用海藻中的碘培育富碘蔬菜防治IDD病的初步研究

以培育“绿色”富碘蔬菜，提高碘的土壤背景值，防治IDD病为目标，利用海带中的碘作为碘肥原料，进行了4种蔬菜的施碘实验。结果表明，通过施加硅藻土海藻碘肥，可培育出含碘量4～120mg/kg的叶菜类蔬菜(菠菜和白菜)和2～30mg/kg的果实类蔬菜(西红柿和萝卜)。不同作物对碘的富集能力不同，其由大到小顺序为：白菜，菠菜，西红柿和萝卜；不同部位对碘的吸收能力也不相同：叶子大于果实和根部。作物通过叶面从空气中吸收碘的能力和通过根部从土壤中吸收碘的能力相当。土壤对碘的保持能力有限，从低施肥量到高施肥量，碘在土壤中的残留率从50％下降到13％。就培育日常食用性蔬菜而言，适宜的施碘量为5～10mg/kg。     

Fatty acid profile of different species of algae of the Cystoseira genus: a nutraceutical perspective

The fatty acid (FA) composition of six macroalgae from the Cystoseira genus, namely Cystoseira compressa, Cystoseira humilis, Cystoseira tamariscifolia, Cystoseira nodicaulis, Cystoseira baccata and Cystoseira barbata, was determined. Polyunsaturated fatty acids (PUFA) corresponded to 29–46% of the total FA detected. C. compressa, C. tamariscifolia and C. nodicaulis stood out for their low PUFA/saturated fatty acid, low n-6 PUFA/n-3 PUFA ratios as well as favourable unsaturation, atherogenicity and thrombogenicity indices, suggesting a high nutritional value with potential applications in the nutraceutical industry.     

海藻中类金属硫蛋白的分离表征及对Zn,Cu的诱导响应

以海带为试验载体,利用葡聚糖凝胶柱,建立了海藻中类金属硫蛋白(MT-like)的分离、提取纯化技术;采用紫外分光光度法比对类金属硫蛋白与兔肝Zn-MTs的紫外吸收,并用凝胶电泳法对其分子量范围进行表征,同时利用质谱法精确测定其分子量;并在ZnCl2,CuCl2,ZnCl2+CuCl2不同条件下胁迫培养藻体,考察了海带对重金属的富集能力,探索藻体中MT-like对Zn及Cu元素的诱导响应。结果显示,MT-like与兔肝Zn-MTs在294 nm处有相似的紫外吸收峰,在SDS-PAGE凝胶电泳图上显像类似,分子量范围相近,经电喷雾离子源质谱测定该蛋白质的分子量约为6.5 ku。另外,海带对重金属的富集能力较强,对Zn元素的富集能力明显高于Cu元素;Zn2+对藻体MT-like的产生有促进作用,而MT-like随着Cu2+诱导时间的增长先增加后降低,且Cu2+对Zn2+诱导存在拮抗效应。     

Synthetic Polyester from Algae Oil

Current efforts to technically use microalgae focus on the generation of fuels with a molecular structure identical to crude oil based products. Here we suggest a different approach for the utilization of algae by translating the unique molecular structures of algae oil fatty acids into higher value chemical intermediates and materials. A crude extract from a microalga, the diatom Phaeodactylum tricornutum, was obtained as a multicomponent mixture containing amongst others unsaturated fatty acid (16:1, 18:1, and 20:5) phosphocholine triglycerides. Exposure of this crude algae oil to CO and methanol with the known catalyst precursor [{1,2‐(tBu₂PCH₂)₂C₆H₄}Pd(OTf)](OTf) resulted in isomerization/methoxycarbonylation of the unsaturated fatty acids into a mixture of linear 1,17‐ and 1,19‐diesters in high purity (>99 %). Polycondensation with a mixture of the corresponding diols yielded a novel mixed polyester‐17/19.17/19 with an advantageously high melting and crystallization temperature.     

Isolation and purification of phycoerythrin from red algaGracilaria verrucosa by expanded-bed-adsorption and ion-exchange chromatography

Summary R-phycoerythrin was isolated and purified fromGracilaria verrucosa on an expanded-bed adsorption column combined with ion-exchange chromatography, which can effectively solve the problem of blockage of chromatographic column due to polysaccharides during isolation and purification of phycobiliproteins. 0.1 M (NH₄)₂SO₄ proved best to elute R-phycoerythrin from the expanded-bed column, and desalted 0.1 M (NH₄)₂SO₄ eluate was used on an ion-exchange column to purify the R-phycoerythrin. Using this two-stage chromatography, the purity (OD₅₆₅/OD₂₈₀) of the R-phycoerythrin fromG. verrucosa is increased to 4.4, and the yield of purified R-phycoerythrin can reach 0.141 mg·g⁻¹ of the frozen alga.     

Arsenic Transformations in Short Marine Food Chains studied by HPLC-ICP MS

The chemical forms of arsenic in some herbivorous or mainly herbivorous marine animals and, in some cases, the algae on which they feed were determined by HPLC-ICP MS. In most cases arsenobetaine was present in the animals as well as arsenosugars consumed directly from the algae. However in the case of copepods Gladioferens imparipes fed only on the diatom Chaetoceros concavicornis which had been grown in axenic culture, arseno-betaine was absent. Arsenobetaine was also absent from the muscle of the silver drummer Kyphosus sydneyanus, although trimethyl-arsine oxide was present. This is the first reported case of the absence of arsenobetaine in a marine teleost fish and may be related to its fermentative faculty for digesting the macroalgae that it consumes. © 1997 by John Wiley & Sons, Ltd.     

Modelling algal densities in harmful algal blooms (HAB) with stochastic dynamics

In this paper, we consider the growth of densities of two kinds of typical HAB algae: diatom and dianoflagellate on some coasts of China’s mainland. Since there exist many random factors that cause the change of the algae densities, we shall develop a new nonlinear dynamical model with stochastic excitations on the algae densities. Applying a stochastic averaging method on the model, we obtain a two-dimensional diffusion process of averaged amplitude and phase. Then we investigate the stability and the Hopf bifurcation of the stochastic system with FPK (Fokker Planck–Kolmogorov) theory and obtain the stationary transition probability density of the process. We obtain the critical values of parameters for the occurrences of Hopf bifurcation in terms of probability. We also investigate numerically the effects of various parameters on the stationary transition probability density of the occurrences of Hopf bifurcation. The numerical results are in good correlation with the analysis. We draw the conclusion that if the Hopf bifurcation occurs with a radius large enough, i.e., if the densities of the HAB algae reach a high value, the HAB will take place with comparatively high probability.     

自然水体生物膜及其对常规重金属吸附的基本特性研究

论述了海藻生物膜生物吸附重金属的研究,阐明生物吸附金属离子技术的特性。同时探讨了重金属吸附的机理和特性,阐明了其吸附过程符合动力学方程、符合logCt=logk (n-1)logt,其中k,n2为常数。     

Cu-FeOx@AC活化PMS体系除藻效能与机制

为探究富营养化水体中藻类的新型治理技术，通过水热法和高温煅烧法，使颗粒活性炭（AC）表层上负载铜铁双金属氧化物Cu-FeO_x，制得可回收的Cu-FeO_x@AC复合催化剂。以XRD、SEM、FTIR和XPS对Cu-FeO_x@AC的表征为基础，研究Cu-FeO_x占AC的负载比、过一硫酸盐（PMS）使用量、初始pH及不同反应体系对除藻的影响，探究Cu-FeO_x@AC活化过一硫酸盐体系的除藻效能。Cu-FeO_x@AC活化过一硫酸盐体系反应机理，通过自由基淬灭实验、XPS表征进行探究。结果可知，初始pH为6，初始藻细胞密度为1.4×10⁹个/L，使用催化剂0.5 g/L，PMS 0.2 g/L时，反应90 min，该体系对藻的降解率有97.25%。在该体系中，藻细胞能被吸附在Cu-FeO_x@AC复合催化剂表面，在铜、铁不同价态离子的转换及AC的协同作用下，产生空穴、·O2-、·OH、SO4-·，单线态氧等多种氧化基团而被去除。