Table of Content

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• Current Biotechnology
  Volume 6 Issue 5 25 September 2016
• Advances on Gene Discovery and Utilization of Wild Relatives of Triticum aestivum L.
• ZHANG Zhi-ming1, TANG Cai-guo2,3, YANG San-wei1, QIAO Lin-yi1, CHANG Jian-zhong1, ZHAO Cui-rong4,5*, ZHENG Jun1*
• 2016, 6(5):  305-311.  DOI: 10.3969/j.issn.2095-2341.2016.05.01
• Abstract ( ) PDF (1149KB)( )
Wheat is one of the most important crops in worldwide, and its production area is the largest in cereal crops. However, the genetic diversity is decreasing because of the long-term directional selection. Therefore, it is difficult to select excellent varieties through interspecific hybridization. Fortunately, many favorable genes exist in wheat related species, such as Secale, Haynaldia, Elytrigia, etc., which have good complementarity with wheat genome. Distant hybridization, therefore, plays an important role in wheat breeding and production in the world. Research progress about diversities, utilization, and problems  of wild relatives of wheat were introduced in this paper. Furthermore, to provide some important information for wheat breeding and genetic research, we discussed the effect and development direction of wild relatives in common wheat improvement.

• Advance on Carbon and Nitrogen Metabolism and Regulation of Tobacco
• ZHANG Sen, XU Zi-cheng*, LI Jing-jing, CHEN Zheng, FANG Xiu
• 2016, 6(5):  312-318.  DOI: 10.3969/j.issn.2095-2341.2016.05.02
• Abstract ( ) PDF (1103KB)( )
The carbon and nitrogen metabolism is the basic metabolic process, affecting the quality of tobacco production. This paper expounded the present situation of the study on carbon and nitrogen metabolism, summarized the influencing factors of carbon and nitrogen metabolites and its key enzyme activity. The paper also summarized the cultivation measures and curing techniques on carbon and nitrogen metabolism regulation. Carbon and nitrogen metabolism plays an important role in the growth and development of tobacco, through the research on carbon and nitrogen metabolism in recent years. We put forward the future research direction of carbon and nitrogen metabolism.
• Review on the Quantification Analysis Methods of Biofilm
• ZHAO Zhi-ying, LI Liang-qiu*, MA Lian-ying, YOU Xue-jiao
• 2016, 6(5):  319-327.  DOI: 10.3969/j.issn.2095-2341.2016.05.03
• Abstract ( ) PDF (1170KB)( )
Because of strong pathogenicity, drug resistance and stress resistance, biofilm has become a major problem of global concern. In this paper, a review was made on the quantitative analysis methods of biofilm biomass, total cell count, living cell number, macromolecular substance and structure, which was expected to provide abandant methods for biofilm research. We are also looking forward to provide theory reference to promote biofilm quantitative analysis method, thereby we can better prevent, control and exploit biofilm.
• Cloning and Expression Analysis of Maize Mediator Subunit Gene ZmMED7#br#
• WANG Jing1,2, ZHAO Jun1,2, ZONG Na1,2*
• 2016, 6(5):  328-335.  DOI: 10.3969/j.issn.2095-2341.2016.05.04
• Abstract ( ) PDF (4988KB)( )
To study the function of maize mediator subunit ZmMED7 gene. We used Real-time Quantitative PCR analysis to study the gene expression levels of ZmMED7-1 and ZmMED7-2 in different tissues and under the conditions of abiotic stress, such as ABA、NaCl and PEG treatment. Results showed that: The expressions of ZmMED7-1 and ZmMED7-2 could be detected in all the tissues sampled at different  development stages, but expression of ZmMED7-1 and ZmMED7-2 were highest at the leaves of V1 and V5 stage. Treated by ABA、NaCl and PEG all lead to decreased expression of ZmMED7-1 and ZmMED7-2. The germination of ZmMED7-1 over-expression transgenic Arabidopsis seeds showed more sensitive to salt stress treatment. ZmMED7 play negative regulator roles in the process of plants responding to salt stress treatment.

• Study on Nutritional Ingredient and Active Contents of the Bulbil and Bulb of Lilium brownii var. viridulum#br#
• ZHU Yun1, WANG Wei2, LI Qian2, CHEN Yao3, ZHANG Wei-jie1, WU Hui-yu4, ZHAO Ting1, MAO Guang-hua3, FENG Wei-wei3, YANG Liu-qing1*
• 2016, 6(5):  336-340.  DOI: 10.3969/j.issn.2095-2341.2016.05.05
• Abstract ( ) PDF (1094KB)( )
Nutritional contents and active ingredient of the bulbil and bulb from Lilium brownii var. viridulum were studied and compared. Nutritional contents of the bulbil and bulb of Lilium brownii var. viridulum were determined by national standard; Active contents of the bulbil and bulb of Lilium brownii var. viridulum were determined by colorimetric method. Compared with the bulb of Lilium brownii var. viridulum, nutritional components analysis indicated that the contents of crude fiber and fat in bulbil had significant difference (P<0.05), the contents of fat in bulbil were lower than that in bulb but fiber were higher, and the content of total sugar, protein and ash in bulbil had no significant difference; the elemental analysis indicated that bulbil and bulb were rich in nutritional elements, and the content of potassium were the highest, which were 1 943.52 mg/100g and 2 026.15 mg/100g, respectively; amino acids analysis indicated that bulbil and bulb had almost the same amino acid composition, and the content of proline in bulbil and bulb were highest, which were 2 260 mg/100g and 2 010 mg/100g, respectively. Compared with the bulb of Lilium brownii var. viridulum, the active contents of total phenol, flavonoids, alkaloid, and saponin in bulbil had significant difference (P<0.05), the content of alkaloid in bulbil were lower than that in bulb but total phenol, flavonoids, saponin were higher, and the total phenol content of the bulbil and bulb of Lilium brownii var. viridulum were 1 025.86 mg/100g and 875.52 mg/100g, respectively. Bulbil and bulb were rich in nutritional components. From the perspective of the exploitation and utilization of resources and nutrition, bulbil had more value to be developed as food resources.
• The TLC Identification and the Cyclovirobuxine D Content Determination in Different Parts of Buxus sinica from Guizhou
• YANG Juan-yan1,2, WANG Fang3, GUO Ting4, WU Lin-lin4, HUANG Hong-mei1, XU Qian-li2, MAO Xiang-jun2*
• 2016, 6(5):  341-345.  DOI: 10.3969/j.issn.2095-2341.2016.05.06
• Abstract ( ) PDF (1559KB)( )
The paper studied the cyclovirobuxine D content of Guizhou Buxus sinica with thin-layer chromatography(TLC) profile,  and compared the cyclovirobuxine D content in different parts of Guizhou Buxus sinica, which was expected to provide scientific basis for the development of Buxus sinica resources. The TLC was used to study cyclovirobuxine D profile in Buxus sinica; a HPLC-CAD method was used to measure cyclovirobuxine D content in different parts of Buxus sinica. Results showed that cyclovirobuxine D spots were clear in the TLC; the main stem had the largest cyclovirobuxine D content but the lowest content in leaves. These methods could be used in thin-layer identification and content determination of the Buxus sinica. In order to reasonable develop and utilize Guizhou Buxus sinica, the best medicinal part is coarse stem.
• Expression of the ω-3 Fatty Acid Desaturase from Mortierella alpina in Wheat-germ Cell-free Protein Expression System
• YANG Qin, CHEN Hai-qin*, CHEN Si, GU Zhen-nan, ZHANG Hao, CHEN Yong-quan, CHEN Wei
• 2016, 6(5):  346-351.  DOI: 10.3969/j.issn.2095-2341.2016.05.07
• Abstract ( ) PDF (2459KB)( )
Cell-free protein expression system as a tool of rapid and convenient protein expression has been widely used in producing membrane proteins and antibacterial peptides that have certain toxicity to living cells. In this paper, the membrane-bound ω-3 fatty acid desaturase gene, which encoding the key enzyme involving in the polyunsaturated fatty acid biosynthesis pathways in the oleaginous fungi Mortierella alpina, was cloned into the in vitro expression vector pIVEX WG1.4, and expressed in the wheat-germ cell-free protein expression system. To get the correctly folded ω-3 fatty acid desaturase FADS15, liposomes that was able to relocate the expressed membrane protein into the phospholipid bilayer were also added in the process of cell-free protein synthesis, and the production of FADS15 reached 1.8 mg/mL, after accudenz density gradient centrifugation, the purity of FADS15 was higher than 90%. This research work paved the way for the further study of catalytic property and crystal structure analysis of this enzyme.

• Optimization of Fermentation Conditions for Recombinant Conotoxin His-Xa-MrVIB
• LIU Yun-hai1, LI Yu1, SUN Fang-jiao1, GAO Bing-miao2*
• 2016, 6(5):  352-356.  DOI: 10.3969/j.issn.2095-2341.2016.05.08
• Abstract ( ) PDF (1658KB)( )
Recombinant conotoxins could be simply synthesized by genetic engineering, and fermentation conditions affect its expression yield. To obtain high expression, the fermentation conditions for engineered E. coli were optimized by using single factor test methods, such as fermentation time, IPTG concentration, initial pH and fermentation temperature. Expression of total protein in the supernatant was measured using a Protein Assay Kit, which was separated in Tricine-SDS-PAGE and the amount of recombinant conotoxins was analyzed by scanning grayscale analysis. The results showed that the optimum fermentation conditions were as follows: fermentation time was 4 h, IPTG concentration was 0.4 mmol/L, initial pH was 6.0, and the fermentation temperature was 26℃, the expression yield was 18 mg/L after optimization. The results laied a solid foundation for large-scale production of conotoxin MrVIB.
• Transition of Distillers’ Grains Biomass by Alkali Pretreatment for Bacillus thuringiensis Cultivation
• SHEN Xiao-juan1, HE Xin-xin2, WANG Yi-bin2, DING Hai-long1, GUAN Xiong2*, DENG Bo1*
• 2016, 6(5):  357-360.  DOI: 10.3969/j.issn.2095-2341.2016.05.09
• Abstract ( ) PDF (1183KB)( )
To minimize environmental contamination and waste of resource, distillers’ grains (DG) from Chinese liquor industry was used to produce reducing sugars for Bacillus thuringiensis (Bt) cultivation. Ca(OH)2 and NaOH were used to pretreat DG at different concentrations and temperatures. HPLC was used to determine the yield of reducing sugars, followed by cultivating Bt using distillers’ grains extract. The results showed that the highest yield of reducing sugars were obtained by  0.75% NaOH for 1 h at 100℃ (81 g/kg). However, the highest spore count was obtained by 1% Ca(OH)2 for 1 h at 50℃, and it was as high as 4.6×107 CFU/mL. DG methods could not only reduce industrial waste and environmental pollution, but also  promote Bt industrialization.
• Antioxidant and Antimicrobial Tests of Extracts from Solid Culture of Isaria farinosa Strains
• WANG Yong-hui1,2§, GUO Chen-yu3§, WANG Wen-jing1*, JIANG Lan1,2, LI Yi4, WU Hong-mei1,2, YAO Yi-jian1*
• 2016, 6(5):  361-365.  DOI: 10.3969/j.issn.2095-2341.2016.05.10
• Abstract ( ) PDF (1090KB)( )
Isaria farinosa is a widely distributed entomopathogenic fungus in soil-dwelling insects. It has been extensively studied and applied in biological control of insects, and also attracted researchers′ attention for its pharmacological effects and bioactive metabolites. In this study, seven strains of I. farinosa from different origins were selected based on morphological and molecular identification to reveal the variation among strains. Antioxidant effects and antimicrobial activities were tested by crude ethyl acetate extracts from the strains cultivated on rice medium. The results showed that the strains displayed significant variations in the bioactivities tested under the same conditions and strain 2142 had the best performance. In particular, the crude extract (200 mg/mL) from strain 2142 had the similar effect with Bacillus cereus to that of ampicillin sodium (80 μg/mL) used as the positive control in the antimicrobial experiment. Further investigation on the strain was required to explore its potentials. There are broad prospects for the application of I. farinosa in health foods and pharmaceutical product, but the caution should be taken in the selection of strains for such purposes. It is important to evaluate the safety of any strain before its application in the area associated with human health.
• Effect of Spinach and Lettuce Planting on Soil Cultivable Bacteria Diversity
• LIU Yi-qian, CHANG Qing, MA Ting-jun, LANG Dan-dan, GONG Han-ying, YI Xin-xin*
• 2016, 6(5):  366-373.  DOI: 10.3969/j.issn.2095-2341.2016.05.11
• Abstract ( ) PDF (1717KB)( )
To study the effect of lettuce and spinach planting on soil cultivable bacteria diversity, and in order to understand the changes of soil bacteria after planting of these two kinds of vegetables, using R2A media, we isolated bacterial strains, and phylogeneticly analized comparison system and preliminary identification of these strains based on 16S rRNA gene sequence. Soil samples grown lettuce were isolated 109 strains of bacteria, mainly belonged to 4 phyla, 19 families, 23 genera. Soil samples grown spinach were isolated 126 strains of bacteria, mainly belonged to 3 phyla, 21 genera and 16 families. In phyla, the dominant bacteria in the soil of planting lettuce were Firmicutes (39.4%), Actinobacteria (33.9%) and Proteobacteria (24.8%); the dominant bacteria in the soil sample of planting spinach were Actinobacteria (64.3%), Firmicutes (27%), and Proteobacteria (8.7%). At the genus level, the difference between the two types of soil samples was greater.
• Preliminary Studies on Tomato Leaf Mould Control by Spraying Acidic Electrolyzed Functional Water
• WANG Bu-yun1, YANG Jin-li2, JIAO Xue-xia2, WANG Xiao-qing1, HU Bin1, SUN Hai1, WANG Yin1, LI Yun-long1, LU Run-gang2*
• 2016, 6(5):  374-378.  DOI: 10.3969/j.issn.2095-2341.2016.05.12
• Abstract ( ) PDF (1074KB)( )
To explore the control effect of acidic electrolyzed functional water against tomato leaf mould, we sprayed different concentration of acidic electrolyzed water in seedling recovering period and early stage of the disease and used 1×106 spores/g Pythium oligadrum as control pesticide. The results showed that it could not only control the disease but also raise the production when 50 mg/L acidic electrolyzed functional water was used once a week in seedling recovering stage and 80 mg/L was sprayed once a week and lasted for three weeks in the early stage of the disease. However, if 80 mg/L was only used in the preliminary stage of disease without any treatment in the seedling recovering period, it had control efficiency on the disease, but had no obvious effect on the production.