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Research Advances of Separation and Purification for Protein
WANG Zi-jia1,LI Hong-mei2,GONG Ai-jun1,CAO Yan-qiu1,YUAN Hai-tao1(1.University of Science and Technology Beijing,Beijing 100083,China;2.National Institute of Metrology,Beijing 100013,China)The method of separation and purification for protein is one of the hotspots of the field for life science.This article summarizes many methods of separation and purification,based on the characteristic of protein′s acid-bases,the size and shape of the molecular,the solubility and the compatibility with legends.
Determination of Vitamin C Content in Five Kinds of Fruits and Vegetables by UV Spectrophotometry
MA Hong-fei,LU Sheng-you,HAN Qiu-ju,LI Wei(School of Environmental and Biological Engineering,Liaoning Shihua University, Fushun 113001,China)The vitamin C contents in five familiar fruits and vegetables were determined by UV spectrophotometry on the basis of the vitamin C characters of UV absorbing and alkali instability.The maximum absorbing wavelength of vitamin C determination by UV spectrophotometry was 243.4 nm,the standard curve equation was A=0.0528c-0.0568,the correlation coefficient R2=0.9996.The vitamin C content in green pepper,citrus junos,cucumber,apple,tomato was 117.1 mg·(100 g)-1,69.3 mg·(100 g)-1,20.5 mg·(100 g)-1,14.9 mg·(100 g)-1 and 18.4 mg·(100 g)-1,respectively.The determination of vitamin C content by UV spectrophotometric method was simple and fast with satisfactory result.
Research and Application Progress of Catalase
LIU Ling-zhi1,2,ZHONG Guang-rong1,XIONG Lian1,2,CHANG Yan-hong2,XIAO Bao-qing2,LUO Hui1(1.Department of Biological Science and Technology,University of Science and Technology Beijing,Beijing 100083,China;2.Department of Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China)As one kind of oxidase,catalase can be found in almost all animals,plants and microorganisms.With high efficiency in peroxide catalyzing,catalases have important potential in industrial applications.On the base of reviewing enzyme classification,functions and structure,this paper focuses on the enzyme purifying and the research progress of catalases from extremophiles,and introduces the applications of catalase on food industry,environmental protection,paper making industry and textile industry.
Comparison and Improvement of Three Determination Methods for Lipase Activity
JIANG Hui-fang,WANG Ya-qin,LIU Chun-guo(Department of Biochemical Engineering,College of Life Science and Technology,Beijing University of Chemical Technology,Beijing 100029,China)Three common lipase activity determination methods including alkaly titrition method,p-nitrophenol(NP) method and copper soap method,aiming at consuming time,accuracy and repeatability,are compared.With an effective way to terminate the reaction being found,the improved p-NP method is stable and rapid.With toluene instead of benzene,the improved copper soap method possesses less toxicity,good stability and repeatability.
Research Progress of Immobilized Enzyme
CHEN Jian-long~(1,2),QI Jian-cheng~1,CAO Yi-zhi~2,GUO Yong~1,DUAN Hui-li~1(1.Institute of Medical Equipment,Academy of Military Medical Sciences, National Engineering Research Center for Biological Protective Equipment,Tianjin 300161,China;2.School of Life Science,Lanzhou University,Lanzhou 730000,China)The immobilized enzymes have been widely applied in many fields for their more advantages than free enzyme,especially for their stability and reusability.At present,immobilization technologies of enzyme have obtained wonderful development.The research of immobilized enzyme will be a very important development field in the enzyme engineering in the future.In this article,various conventional and new methods for preparation of immobilized enzyme are introduced. At the same time,the immobilization of enzyme on some carriers with excellent properties are reviewed.
Determination of the Activity of α-Amylase by Visible Spectrophotometry
ZHANG Xuejiao;TIAN Huan;LIU Chunye;YOU Jing;According to the characteristic absorption of complex formed by I~-3 and starch,the activity of α-amylase is determined by visible spectrophotometry,which is determined through the amount of starch hydrolyzed before and after adding α-amylase.From the experimental results,we find that the maximum absorbance of complex is at 580 nm,and the color is stability in Na_2HPO4-citric acid buffer with pH value of 6.5.When a certain amount of starch is added,changing the concentration of α-amylase from 0.001-0.008 mg·mL-1,there is a good linear relationship between the concentration(x) and the activity(y) of α-amylase,and the linear equation is y=375.75x+0.1208(R2=0.9939).This method can be used to determine the activity of α-amylase.
The Research Progress in Gene Knock Out
LIU Jian-zhong~(1),AO Jing~(1),TIAN Wei-yu~(1),MA Ji-hua~(2)(1.College of Chemical Engineering,Source,and Environment,Wuhan University of Science and Technology,Wuhan 430081,China;2.College of Medical Science,Wuhan University of Science and Technology,Wuhan 430081,China)Gene knock out was a very important technique to study the roles of functional genes,and it was also a very important research branch in the post-genome period.In this paper,the cell basis for gene knock out,the construction of the vector for gene knock out and the screening of the embryonic stem cells where homologous recombination occured,the animal models made after gene knock out,gene knock out and gene rescue,the research progress of gene knock out at home and the problems existed were briefly introduced.
Research Progress in Remediation Technology of Heavy Metal Contaminated Soil
WANG Xingli;WANG Chenye;WU Xiaochen;WANG Jingbo;MU Xiaodong;YANG Xiaoshu;HU Xiaofei;GAO Jing;Hainan Institute of Environmental Sciences;With the rapid development of industry and agriculture,China is facing a severe situation of soil heavy metal pollution.The remediation of heavy metal contaminated soil has become an important issue in the field of ecological environment,which has attracted extensive attention.On the basis of the frontier of remediation technology for heavy metal contaminated soil at home and abroad,we shortly introduce the main sources of soil heavy metal pollution.Meanwhile,we expound and analyze the main remediation technologies of heavy metal contaminated soil in detail,such as physical remediation,chemical remediation,and biological remediation,etc.Aiming at the characteristics and disadvantages of various remediation technologies,we put forward the improvement and development directions of remediation technologies for heavy metal contaminated soil in the future,which provide a reference for the research of soil remediation.
The Development of Extraction of Caffeine in Tea
ZHAO Wei-xing1,JIANG Hong-bo2,FENG Guo-dong1 (1.Department of Chemistry & Chemical Engineering,Baoji University of Arts & Sciences,Baoji 721013,China;2.Department of Mechanical and Electrical Engineering,Baoji University of Arts and Sciences,Baoji 721016,China)Caffeine,an alkaloid in tea,plays an active role in human health for it possesses important physiological actions.Modern medical research shows that caffeine is a stimulant for central nervous system,and it can boost metabolism and affect the function of nerves,heart and kidney.At present,caffeine in tea can be extracted by a variety of ways,among which there exists a large difference in extraction rate and product purity.This article focuses on the development of extraction of caffeine in tea.
Progress in Synthesis and Applications of Polypeptides
LI Yong-zhen1,2,HE Ji-dong2,PENG Zheng1,LI Xi-juan3(1.Key Laboratory of Rubber-Plastics,Ministry of Education,Qingdao University of Science and Technology,Qingdao 266042,China; 2.Key Laboratory of Tropical Crop Products Processing,Ministryof Agriculture of China,Agro-Food Processing Institute,Chinese Academy of Tropical Agricultural Sciences,Zhanjiang 524001,China;3.Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences,Danzhou 571700,China)The first part of this paper focuses on reviewing the methods of synthesizing polypeptides from two aspects: chemosynthesis and biosynthesis.Especially the methods which developed in recent years,such as: N-carboxyanhydrides(NCA),peptide liquid-phase segments ligation,combinatorial chemistry,enzymatic hydrolysis,gene engineering,fermenting and so on are taken as examples.After describing the method,the relative merits of each method are appreciated.At the second part of the paper,the applications in polypeptide drugs,drug carrier,tissue engineering and enriched food are summarized.At last,the prospect of polypeptide industry in China is forecast.