Table of Content

20 November 1997, Volume 33 Issue 6

Previous Issue    Next Issue

Comparative Studies on Some Amino Acids of Panax Species

LI Qi,YE Yunhua,XING Qiyi,YUAN Hongsheng

1997, 33(6):  686-690. 

Asbtract ( )  

Related Articles | Metrics

The content of Trp, Asn. Gln and some non-protein amino acids were analyzed and compared by several methods on two different amino acid analysers. Results show that the content of Trp, either free or combined, in Jilin Ginseng is higher than that in Korean red ginseng. The content in Notoginseng is the lowest. In certain species, the content of combined Trp is higher than that of free. The content of Asn, Gln, and some non-protein amino acids, such as Orn, Citrullioe, Ethanolamine and alpha-Aminoadipic acid etc., have been reported.

Studies on the Electrochemical Behaviors of the Olaquindox

ZHANG Chengzhi,HE Weijun,LI Nanqiang

1997, 33(6):  691-698. 

Asbtract ( )  

Related Articles | Metrics

The electrochemical behaviors of the olaquindox were studied in acetate and phosphate buffer solutions respectively. In the phosphate buffer solution, at pH=7.0, two sensitive adsorptive waves were obtained by single-sweep polarography. The second peak height (h_p2) of derivative wave is proportional to cola from 4×10^-8 to 2×10^-5mol/L. The detection limit is down to 1×10^-8mol/L. On the surface of mercury electrode, the adsorption of olaquindox obeys Frumkin isotherm. The adsorption coefficient β=9.1×10⁴ and the interaction factor v=0.8 were determined. In acetate buffer solution, at pH=4.5, three adsorptive waves can be obtained. The rate constants of the surface electrode reaction as k_s1=2.1s^-1，k_s2=2.2s^-1，k_s3=1.8×10³s^-1were determined. The mechanisms of electrode reactions were discussed in the two buffer solutions.

Studies on the Application of Tartaric Acid to the Synthesis of Chiral Compounds Ⅰ The Synthesis of L-(-)-2, 3-O-methylidene Threitol and L-(+)-2, 3-O-isopropylidene Threitol

NIE Aihua,CHEN Xinchao,CHEN Yezhong,YE Xiulin

1997, 33(6):  708-711. 

Asbtract ( )  

Related Articles | Metrics

Simple but efficient procedures were proposed for preparation of L-(-)-2, 3-O-methylidene Threitol and L-(+)-2, 3-O-isopropylidene Threitol in the present paper. It is suggested to use these two thretols as the chiral precursors of synthesizing (-)-anisomycin.

FT IR Study on the Secondary Structure of Earthworm Calmodulin(CaM) and the Effects of Ca²⁺ and Tb³⁺ Ions

WANG Libo,WU Jinguang,XU Guangxian,WANG Caiqing,ZHANG Tingfang

1997, 33(6):  699-707. 

Asbtract ( )  

Related Articles | Metrics

The Secondary structure of earthworm Calmodulin(CaM) in thin film was measured by using FT-IR spectroscopic method and curve fitting technique, and the effects of Ca²⁺ and Tb³⁺ were investigated in detail. The results show that CaM exhibits lower content of α-helix and relatively higher contents of β-sheet and beta-turn structure in film than that in crystal or water solution. To some extent, the addition of different ratios of Ca²⁺ and Tb³⁺ induced different conformation changes, which indicates that the two ions have different combination mechanisms. Moreover, the activity to stimulate the PDE enzyme and the SDS-PAGE behavior of CaM with different metal ions were also studied. The results show that Tb³⁺ can active CaM under low concentration, but inhibit the activity of CaM under high concentration, which suggests that Tb³⁺ have different physiology role from Ca²⁺.

The Condensation of Crotonaldehyde or 3-Hydroxybutanal with Meldrum's Acid

JIAO Yuguo,ZHANG Pang

1997, 33(6):  712-715. 

Asbtract ( )  

Related Articles | Metrics

Condensation of Meldrum's acid with crotonaldehyde or 3-hydroxybutanal in the presence of ethylene diammine diacetate yielded 2-butenylidene Meldrum's acid rather than parasorbic acid as Stevenson and Weber, then we studied the possibility of 2-butenylidene Meldrum's acid to form a cyclo-compound.

Spectrophotometric Determination of Amrinone in Pharmaceutical Preparations Based on Charge-Transfer Complex

XU Bianzhen,ZHAO Fenglin,TONG Shenyang

1997, 33(6):  716-719. 

Asbtract ( )  

Related Articles | Metrics

The charge-transfer complex(CTC) of chloranil with Amrinone was studied in detail by spectrophotometry. A new method for the determination of Amrinone has been established. The determinations were carried out in ethanol solution at 409nm. Beer's law is obeyed in the concentration range of 0-40mg/L. The apparent molar absorptivity was 5.86×10³L·mol^-1·cm^-1. The composition is 1:1. The proposed method was applied to determination of Amrinone in pharmaceutical preparations and satisfactory result was obtained.

Study on the Effective Composition of Skimmia laureola

ZHANG Hongjie,ZHANG Mingzhe

1997, 33(6):  720-724. 

Asbtract ( )  

Related Articles | Metrics

Five compounds were separated from the herb plant Skimmia laureola ssp. multinervia collected from Yunnan Province of China. They were identified as O-methyllaureolol(I), taraxerone(II), (-)-evoxine(III), kokusaginine(IV) and haplopine(V) by UV, IR, ¹H-NMR and ¹³C-NMR, in which compound I is a new compound.

Study on the Effect of the Concentration of Na⁺ and Li⁺ on Mass Spectral Fragmentation of An Acetylated Melezitose with Fast Atom Bombardment

HE Xiaoran,LIN Xiaoyuan,YU Zhenpei,HE Meiyu

1997, 33(6):  725-730. 

Asbtract ( )  

Related Articles | Metrics

The dependence of the relative intensity of cationic molecule and fragmentation ion of an acetylated melezitose on the concentration of Na⁺ or Li⁺ in the matrix was studied by using fast atom bombardment source. It implies that the mass spectrum with complete structural information can be observed in a proper range of the concentration of Na⁺ or Li⁺.

Studies on CaM-binding Proteins from Earthworm

ZHANG Yanhong,ZHANG Tingfang

1997, 33(6):  731-735. 

Asbtract ( )  

Related Articles | Metrics

Calmodulin-binding proteins were purified from earthworm (Eisenia Foetida) by a procedure involving DEAE-Fast Flow, CaM-Sepharose 4B chromatographies. The purified CaM-binding proteins inhibited the activity of CaM-dependent PDE and the degree of inhibition increased with augmentation of the CaMBPs. But this inhibition could be eliminated by adding an excess of earthworm CaM. This appeared to be the typical character of CaM-binding Proteins. Three main bands of purified CaMBPs were shown on SDS-PAGE with apparent molecular weight of 62, 49 and 30kD. Their content percent was determined as 7.17%, 7.31% and 51.8% by gel scaning respectively. Three kinds of CaMBPs were detected by biotinylated CaM-overlay method. The assay of enzyme activity indicates that there was CaM-dependent Ca²⁺-ATPase activity, but no NAD kinase one.

Synthesis of Hirudin Gene by Recursive PCR and Its Expression and Secretion in Escherichia coli

BI Qun,HUANG Yixiu,ZHU Shenggeng

1997, 33(6):  737-742. 

Asbtract ( )  

Related Articles | Metrics

According to the amino acid sequence of hirudin HV-2, six pieces of polynucleotides were designed and chemically synthesized. The whole hirudin gene was constructed with these polynucleotides by recursive PCR. Then the synthetic gene was inserted into the secretary expression vector, pIN-ompA-HI. The recombinant plasmids were introduced into competent cells of E.coli strain DH 5a. Its DNA sequence was determined, proved to be the same as designed. The hirudin gene was expressed in E.coli. The recombinant product was secreted into the periplasm and medium, and antithrombin activity could be detected. The expression level was 19.8% of bacteria total proteins. The product was purified by salting out, gel filtration chromatography, and ion exchange chromatography. SDS-PAGE of the product showed a single band of 12k Da(as a dimer)and mass spectrometry showed the molecular weight of 6893.1 Da. It is suggested that the recombinant hirudin has been processed correctly during the secretion.

Defence Responses of Tenebrio Moliter Larvae

REN Shuxian,WANG Rongjiang,HAN Zheng

1997, 33(6):  743-748. 

Asbtract ( )  

Related Articles | Metrics

The hemolymph defence responses of the larvae in last instar of Tenerio moliter were experimentally studied. The results were that: (1) When the larvae were stimulated by a needle and injected with Escherchia coli, Bacillus thuringiensis and sterile saline severally, the total hemocytes count (THC) in all treatments changed regularly in the similar way: first, THC reduced sharply in 15 min postinjection, then three peaks of THC occured within 10h postinjection, but the scope of the change was different. (2) The remnant quantity of bacteria in the larvae reduced gradually when the larvae were injected with the two kinds of bacteria. The peak of THC accompanied with a peak of disinfection. The peak of the rate of relative disinfection occured in 1～2h and 4～6h postinjection. (3) The inducement period of humoral defence of the larvae was 6～8h postinjection, so the cellular reaction occured in the early to microbial invaders and humoral defence reaction participated in 6～8h postinjection.

Study on Ecological Habits of Potamogeton crispus and Its Growth in Jing-Mi Canal, Beijing

REN Jiuchang,QIAO Jianrong,DONG Wei,DAI Changliang

1997, 33(6):  749-755. 

Asbtract ( )  

Related Articles | Metrics

The over-growth of Potamogeton crispus in Jing-mi canal has resulted in the obstruction of water flow during recent years. Using approaches of laboratary experiment and field investigation, P.cripspus is a kind of submerged macrophyte, its ecological habits, development stages and population dynamics has been carried on in this paper. P.cripspus has a natural inclination for low water temperature. The phrase of turion over summer and germling over winter are two specific property of the life history of P.crispus. It grows expeonentially in later spring and early summer, making its biomass accumalation curve in S shape. P.crispus happens in every section of Jing-mi Canal, and grows best in the lower reaches of the Canal during May and June, where the water is on meso-eutroficational state. The manage measures and optimum time of controlling P.crispus are mentioned in this paper.

Seed Dormancy in Acacia mangium

FU Jin,YOU Ruilin,GU Zenghui

1997, 33(6):  756-762. 

Asbtract ( )  

Related Articles | Metrics

The seed coat of Acacia mangium was investigated by light and scanning electron microscopy. The testa comprises a palisade epidermis, an osteosclerid layer and a thick-walled parenchyma with lignified walls, a thin cuticle covering a pectinaceous subcuticular layer which together form the outer covering of the layer of palisade cells. It is indicated that the impermeability barrier lies in the palisade layer, and suggested that light line zone situated on the outer ends of the palisade is surrounded by a compact layer of cellulous, which is probably responsible for the optical phenomenon known as the light line.

Kinetics Study of the Cleavage of Cu-thionein Centers in Mammalian CuMT and (Cu, Zn)MT Induced by H₂O₂

HUAI Qing,FANG Xingwang,WANG Wenqing

1997, 33(6):  763-769. 

Asbtract ( )  

Related Articles | Metrics

Typical UV of CuMT scans from 220 to 350nm and exhibits a shoulder near 260nm. Cleavage of Cu-sulfur bond was detected by the decrease of absorbance of 260nm in UV spectra. Kinetics of the H₂O₂ dependent cleavage of Cu-thiolate centers in copper reconstituted mammalian CuMT was studied. The kinetics type and the possible linear dependency of the rate constants on the H₂O₂ concentration were performed. The cleavage of Cu-thiolate center in CuMT was compared with that of (Cu, Zn)MT. The results first show that zinc can stabilize the Cu-S chromophore in (Cu, Zn)MT directly.

A Free-form Digital Image Stretching Algorithm Based on Linear Transformations

ZHOU Bingfeng

1997, 33(6):  770-775. 

Asbtract ( )  

Related Articles | Metrics

A free-form image stretching algorithm is presented. By establishing a linear mapping from destinate image to the original image, the algorithm utilizes the rasterlization algorithm of polygons to accomplish the stretch. The algorithm can stretch an original rectangular image into an arbitrary quadrangle. In this algorithm, many basic geometric transformations of digital images are unified. These transformations include scaling, rotating, shearing, flipping, and mirroring, etc. The algorithm can also support some complex geometric transformations by using the image subdividing technique. An example of this is given.

Extension Technology in Publishing Software

LI Pingli

1997, 33(6):  776-784. 

Asbtract ( )  

Related Articles | Metrics

This article focuses on the extension technology of publishing software. It introduces several famous extension frames. By using the latest technologies, the author sets up an Object-Oriented extension scheme-the Software Component Hierarchy. This article explains the technical background and the main thought of the Software Component Hierarchy and compares it with the other extension frames. The Software Component Hierarchy has been applied in the designing of the latest publishing software of Founder Corporation and has showed its power on the market.

Studies on the Synthesis of Sesamin-Group Lignans VII. Selective Oxidation of 2-Arylfuran-3, 4-dicarbinol

CHEN Bingzi,CHENG Peng,PEI Weiwei,YE Xiulin

1997, 33(6):  785-787. 

Asbtract ( )  

Related Articles | Metrics

Tetrakis-pyridinocobalt (II)-dichromate [(HCrO₄)₂-Py₄-Co(II)] was used for the selective oxidation of 2-arylfuran-3, 4-dicarbinol to 2-arylfuran-3- carbinol-4-carbinal in about 60% yields.

A Study on the Microsporogenesis and theDevelopment of the Male Gametophyte in Cimicifuga Nanchuanensis, an Endangered Plant

ZHANG Yingtao,CHENZHU Xizhao,QI Wenqing,YOU Ruilin

1997, 33(6):  788-793. 

Asbtract ( )  

Related Articles | Metrics

The microsporogenesis and the development of the male gametophyte are basically normal and a large quantity of functional pollen grains can be produced in Cimicifuga nanchuanensis (Ranunclaceae). However, many kinds of abnormal phenomena exist in their developmental processes in a low ratio. No weak links causing this species endangerment were detected in their stamen development.

Rate of Evolution and Unification of Evolution Theories

ZHANG Yun

1997, 33(6):  794-803. 

Asbtract ( )  

Related Articles | Metrics

The recent debates between different evolutionary views involved mostly in rates of evolution. Contradictory conclusions have been drawn from the studies of evolution rate at different levels of organization, and led to exclusion between different doctrines of evolution. The random molecular evolution with a stable and uniform rate, interpreted by the neutral theory, is in conflict with the nonuniform adaptive evolution at phenotypic level; the adaptive and gradual evolution under natural selection at population level, advocated by the modern synthesis based on microevolution, could not coupled with the "punctuated", "explosive" or "catastrophic" macroevolution, demonstrated by fossil records. These contradictions were mostly resulted from using different variables for measurement of evolution rates. The rates of evolution measured at different levels of organization may have different senses, thus the controversies between the different doctrines may have no equivalent words. The timing of major evolutionary events in the long history of life on Earth shows apparent nonuniformity:most important evolutionary events occurred in the earliest and latest stages of the life history, and in relatively short time. The prebiotic chemical evolution, origins of life, the fundamental cell structures and metabolic pathways, and the foundations for biological evolution and biosphere formation were established in about 300-500 Ma time interval in the beginning of life history (4.0 to 3.5 Ga ago). Emergence of the advanced organisms and remarkable increase of biodiversity, as well as most major innovation of organism structures took place in the latest stage of life history (since 700 Ma). This nonuniformity of megaevolution here is interpreted as the results of coevolution between the life and the Earth's physical environments. The present dissension in evolution theory is temporary, resulted from the progresses of biology and related sciences. The different doctrines of evolution will certainly toward to unification and to a new synthesis.