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Synthesis and Characterization of Graphene by Improved Hummers Method
HONG Fei,ZHOU Li-qun,HUANG Ying,SONG He-juan,WANG Ting,LUO Xin-ru,WU Zhen(College of Chemistry and Chemical Engineering,Hubei University,Wuhan 430062,China)Based on the improved Hummers method,the precusor graphite oxide(GO) was synthesized from flake graphite,and then graphene was prepared by using sodium borohydride as reductant.Graphite oxide and graphene were characterized by FTIR,XRD,TEM and SEM.The results showed that graphite oxide was high in oxidation degree and contained various oxygen functional groups such as-OH,-COOH,C-O-C,and graphene had two-dimensional nano-flake structure with curly edge.
Application of Genome-Wide Association Study for Important Traits in Plant
TU Yu-chen1,2,TIAN Yun1,2,LU Xiang-yang1,2(1.Hunan Agricultural Bioengineering Research Institute,Changsha 410128,China; 2.College of Bioscience and Technology,Hunan Agricultural University,Changsha 410128,China)Genome-wide association study(GWAS) has been widely employed to investigate important traits in plant genetics and breeding.Association study is an approach to recognize the relationship between molecular markers or candidate genes with traits in a given population based on linkage disequilibrium.The development background,research principle and research strategy of GWAS were introduced in this paper,and the application progress of GWAS in the research of important plant genetic loci was reviewed.
Extraction Process Optimization,Content Determination,and in vitro Antioxidant Activity of Licoflavone
ZHANG Guanghui;ZHANG Shuan;JIN Ruyi;MENG Qinghua;Using 95% ethanol as an extraction solvent and extraction rate as an evaluation index,we optimized the extraction process of licoflavone from different producing areas by response surface methodologies.Moreover,using rutin as a reference substance,we determined the content of licoflavone from different producing areas by sodium nitrite-aluminum nitrate-sodium hydroxide colorimetric method.Furthermore,we compared in vitro antioxidant activity of licoflavone from different producing areas by scavenging DPPH free radicals.The results show that the optimum ethanol extraction conditions of licoflavone are determined as follows:the extraction temperature of 86.7 ℃,the extraction time of 4.0 h,and the liquid-solid ratio of 80.0∶1.0(mL∶g).Under above conditions,the contents of licoflavone in Gansu,Xinjiang,and Inner Mongolia are 18.22 mg·g-1,17.75 mg·g-1,and 16.82 mg·g-1,respectively,and the scavenging rates of DPPH free radicals are 63.82%,62.74%,and 51.41%,respectively.The order of the licoflavone content and the in vitro antioxidant activity of three producing areas is Gansu>Xinjiang>Inner Mongolia.This conclusion can be used as one of the references for origin identification and quality evaluation of licorice,and can provide help for the development and utilization of licorice.
Research Progress of Biotransformation in Natural Product Chemistry
WANG Yu-dan,CHENG Gui-guang,YU Xu-ya,WANG Ya-ming (Faculty of Chemical Engineering,Kunming University of Science and Technology,Kunming 650224,China)With the rapid development of biology science,biotransformation is applied in research of natural product chemistry.The application and progress of biotransformation in natural product chemistry were reviewed.Several major chemical reactions of biotransformation in natural product chemistry were introduced.The prospect of biotransformation was anticipated.
Optimization in Extraction Process of Pectin from Amomum tsaoko by Orthogonal Experiments
XIE Xin;LI Liyuan;LI Tong;CHEN Xiaoni;HUANG Suoyi;We extracted pectin from Amomum tsaoko by a traditional acid hydrolysis ethanol precipitation method.Meanwhile, taking the yield of pectin from Amomum tsaoko as an evaluation index, we optimized the extraction process of pectin from Amomum tsaoko by L9(34) orthogonal experiments on the basis of single-factor experiments.The results show that the order of the influence of each factor on the yield of pectin is pH value>solid-liquid ratio>extraction time>extraction temperature.The optimal extraction process is as follows: the pH value of 3.0,the extraction temperature of 90 ℃,the extraction time of 150 min, and the solid-liquid ratio of 1∶30(g∶mL).Under above conditions, the yield of pectin is 7.54%,which provides scientific basis for the further development of Amomum tsaoko resources.
Research Progress in Preparation and Application of Tricobalt Tetroxide
TANG Chunni;Tricobalt tetroxide is widely used because of its characteristics of low cost,good stability,and high catalytic activity and having abundant resources.We introduce the basic properties of tricobalt tetroxide,and review the research progress of the preparation methods and application of tricobalt tetroxide.This paper provides a reference for the development and application of tricobalt tetroxide.
Research Progress on Antimicrobial Bioactive Substances from Marine Microorganisms
BAI Feng-yue;NI Meng-xiang;Marine microorganisms can produce many bioactive substances with novel structures due to their special metabolic behaviour,so they are considered as potential resources for natural drugs discovery.The research progress on antimicrobial bioactive substances from marine microorganisms in recent three years is reviewed and their future development prospects are also presented.
Research Advance on Plant Endophyte
WANG Li-heng(Department of Life Sciences,Xi′an University of Arts and Science,Xi′an 710065,China)Plant endophytes are the new microorganism resources with great investigative significance and potential applied value,which have become one of the most popular research topics in recent years.In this paper,general situation and research advances and biological functions of plant endophyte were summarized for further understanding of interactions of endophytes and host plants.
Research Progress in Extraction of Flavonoids with Green Deep-Eutectic Solvent
FU Jiale;GENG Zhi;As a new green solvent,deep-eutectic solvent has stimulated enormous research interest of researchers since its inceptive preparation in view of the characteristics of wide range of dissolution,simple preparation,and biodegradability.In this paper,we introduce the classification of deep-eutectic solvent,expound the factors affecting the extraction of flavonoids with deep-eutectic solvent,and discuss the biological activity of flavonoids extracted with deep-eutectic solvent and the recovery of solvent,in order to provide a reference for the development and research of flavonoids.
Application of Red Homologous Recombination in Gene Knockout of E.coli
L Shen-cong,ZHAO Ying-ying,ZHONG Wei-hong(College of Biological and Environmental Engineering, Zhejiang University of Technology,Hangzhou 310032,China)Gene knockout technique of Escherichia coli is developing rapidly.Emerging of various kinds of new technologies has simplified the genome modification of E.coli than before.Especially,the Red homologous recombination system becomes more and more mature in gene knockout of E.coli.In this article,a few different kinds of Red homologous recombination technologies were reviewed.The mechanism and application strategies of each method were analyzed with its characteristics and superiority highlighted.