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October 15,2012
Volume 5,Issue 19
Pages -
Subject Area:Forest?Management,Chemical Processing of Forest Products,Agricultural Mechanization,Agricultural Engineering,Crop Physiology,Food Processing Technology,Food Fermentation and Brewing Technology

Title: Effects of different rotation on carbon sequestration in Phoebe bournei plantation forests using FORECAST ecosystem model

Authors: WANG Weifeng, WEI Xiaohua, LIAO Weiming, LIU Yuanqiu, Juan A BLANCO
PP: 1892-1903
Abstract: In this study, the forest ecosystem model, FORECAST was used to simulate the effects of different management strategies on carbon sequestration in phoebe forests. Data on forest biomass, stand density, light response curve and soil nutrients under different site conditions were collected from field surveys or published papers. After the model calibration and validation, FORECAST was run with various management scenarios including different rotation lengths. The main conclusions are as follows: The rotation length of 80 years is superior to shorter rotation (eg: 20 years or 40 years). Rotation length is important for influencing forest carbon sequestration with a longer and higher carbon sequestration. Phoebe bournei plantations has obvious role on soil improvement, especially on the poor site. As a hardwood species, Phoebe produces a large amount of decomposition litter and nutrients, which is important for maintaining high carbon sequestration.
Keywords: forest management; FORECAST ecosystem model; Phoebe bournei plantations; rotation; carbon sequestration

Title: Study on homogeneous acetylation moditication of chitosan in ionic liquids

Authors: LIU Lu, ZHOU Shuai, WANG Bo, MA Mingguo, XU Feng, SUN Runcang
PP: 1885-1891
Abstract: The acetylation of chitosan was investigated in homogeneous chitosan/ionic liquid system, and the effect of reaction parameters, such as reaction time, temperature, and the molar ratio of acylated reagent to glucosamine unit on degree of substitution (DS) was studied. In 5% mass fraction chitosan /1-allyl-3-methylimidozalium chloride ［Amim］Cl, 86.5% DS was obtained in the 6∶1 molar ratio of acetyl chloride to chitosan at 60℃ for 12 h. The chitosan DS just decreased slightly to 77% after ［Amim］Cl was reused five times, demonstrating the good reusability of ionic liquids. This process combined the advantages of the excellent product separation methodology with nice DS result, which is expected to contribute to the development of green and environmentally friendly strategy for industrial chitosan derivatives.
Keywords: chemical processing of forest products; natural polymer; chitosan; derivatization; homogeneous acylation; ionic liquids

Title: Nano-modified wood coatings and its effect on VOC degradation of wood-based panels

Authors: LIU Yu, ZHU Xiaodong
PP: 1881-1884
Abstract: In order to improve the environmental performance of waterborne polyurethane, TiO2 were added to prepare the modified waterborne polyurethane with high volatile organic compounds (VOC) degradation properties. The nano-modified wood coatings were prepared by reacting waterborne polyurethane with TiO2. Efficiencies of VOC degradation under different TiO2 content, coating thickness and light source were calculated according to VOC concentrations of wood-based panels. The VOC degradation under UV light was higher than that of daylight, with the increasing of TiO2 content, the total volatile organic compound (TVOC) degradation of modified waterborne polyurethane was enhanced obviously, while the thickness of coatings had little effect on VOC degradation.
Keywords: wood processing and wood-based panel technology; wood-based panels; volatile organic compounds; waterborne polyurethane; photocatalytic degradation

Title: Study on the force distribution of agricultural fiber materials during high-density compressing in the baling chamber

Authors: CHEN Daxing, WANG Hongbo, WANG Chunguang
PP: 1877-1880
Abstract: In this paper, the crumbled yellow corn stalks and the high-density compressing apparatus were respective test materials and test equipment. This study chose three different feed rates i.e 5, 4, 3 kg/time, and three different compression frequencies i.e 15, 18, 21 times/min, as the test conditions. The three-dimensional distribution law of force field in the chamber during compressing was obtained through testing the force distribution of crumbled yellow corn stalks during high-density compressing in the compression chamber. This paper provided the basis for the design and optimization of corresponding mechanical equipments.
Keywords: agricultural mechanization; corn stalks; high-density compressing; force distribution

Title: Analysis on influence of hydrological time series length on chaotic identification

Authors: YU Xinwei, LIU Dong
PP: 1871-1876
Abstract: According to the observed precipitation data from Qixing farm of Jiansanjiang during 1957-2010 and based on the phase space reconstruction technique, G-P algorithm, the correlation dimension and the Kolmogorove entropy of different length sequence for 72 months, 216 months and 648 months were calculated respectively. The results showed that: 1) Chaotic characteristics of monthly precipitation time series of Qixing farm was existed. 2) The delay time was τ=3 months, the smallest dimension was m=7, the sequence length had little influence on the selection of the delay time and the smallest dimension. 3) Saturation correlation dimension method was unsuitable for chaotic identification for a small amount of data. With the longer sequence length, the correlation dimension reached saturation more easily. 4) The Kolmogorove entropy method could deal with different lengths of time series, and with the longer sequence length, the Kolmogorov entropy was more easily stabilized. This research provided the scientific basis for the further improvements and applications of chaos theory in hydrology, and it had a certain significance for precipitation time series analysis of Jiansanjiang.
Keywords: agricultural engineering; precipitation time series; phase space reconstruction; correlation dimension; Kolmogorov entropy; precipitation

Title: Spatial predicition of soil properties based on Bayesian maximum entropy and historical data

Authors: YANG Yong, LI Weidong, HE Liyuan
PP: 1864-1870
Abstract: In this paper, soil organic matter distribution of 2005 and soil sampling of 2009 in Hannan, Wuhan were used as experimental data, and Bayesian maximum entropy (BME) was used to estimate spatial distribution of soil continuous properties. The soft data was calculated with soil organic matter distribution of 2005 based on cumulative probability distribution function, and soil was sampling data of 2009 was used as hard data. The prediction performance of BME was compared with that of Kriging under different densities. It was found that BME was more accurate, especially in the case of less sample points, the advantages of the BME method were more obvious. Finally, The advantages and disadvantages of the BME method was discussed.
Keywords: soil science; Bayesian maximum entropy; soft data; soil properties; spatial prediction

Title: Effects of periplocoside NW from Periploca sepium on intracellar［Ca2+］ in of adults of Mythimna separata muscle cells

Authors: HU Zhaonong, LIAN Xihong, LIU Jian, WU Wenjun
PP: 1858-1863
Abstract: To understand the insecticidal mechanism of periplocoside NW (PSNW) isolated from Periploca sepium, the effects of PSNW on the muscle intracellular ［Ca2+］ of Mythimna separata adults were determined by means of laser confocal microscope together with calcium fluorescent indicator. The results showed that the intracellular ［Ca2+］ decreased when treated with high concentration (μmol/L~mmol/L level) of PSNW, while the intracellular ［Ca2+］ raised when treated with low concentration (nmol/L level) of PSNW. These results suggested that the intracellular calcium channel of muscle cell might be one of the action targets of PSNW.
Keywords: pesticide science; botanical insecticide; periplocoside NW; Mythimna separata; intracellular Ca2+ channel

Title: Cloning and cellular expression of peptidoglycan recognition protein from diamond back moth (Plutella xylostella L.)

Authors: XU Xiaoxia, WANG Ruixiao, SUN Qiang, LI Linmiao, XU Yingjie, GAO Gang, HUANG Wanjun, WANG Shuang, JIN Fengliang
PP: 1850-1857
Abstract: Peptidoglycan recognition proteins (PGRPs) are one of the pattern recognition receptors which can recognize the peptidoglycan or a class of bacterial containing the peptidoglycan. They play an important role in the regulation and recognition of innate immune response. In this paper, a full length cDNA sequence encoding PGRP was cloned from Plutella xylostella L. by homology and rapid amplification of cDNA ends (RACE) technology (GenBank accession No. EU399240, defined as PxPGRP). The analysis of sequence showed that PxPGRP contains an open reading frame (ORF) of 588 bp, encoding 195 amino acids, with the predicted MW of 21 ku and pI of 8.38, while the mature protein encoding with the predicted MW of 19.04 ku and pI of 8.86. The temporal and partial expression profiles of PxPGRP were investigated by semi-quantitative PCR and real-time quantitative PCR. The analysis of semi-quantitative RT-PCR showed that PxPGRP could be expressed at each instar stage, especially with higher expression in 4th instar and pupae of P. xylostella. The analysis of real time PCR showed that the mRNA transcription level PxPGRP was tissue specific, and the level was from high to low in proper order of epidermis, malpighian tubules, fat body, hemocyte and midgut. In order to obtain recombinant protein and lay a basis of structural and functional study of PxPGRP, the ORF of PxPGRP was ligated into pEGFP-C3(+). The converted fluorescence microscopy confirmed that PGRP had a higher expression in Sf9 cells after transfection. The successful expression of PxPGRP in cells not only lays a foundation for the structural and functional study, but also provides a new target for the biological control of P. xylostella.
Keywords: plant protection; Plutella xylostella; peptidoglycan recognition proteins; clone; cellular expression

Title: Study on cloning and functional characterization of the ribosomal protein-related genes RPS18, RPL30 and RPL32-B in Cryphonectria parasitica

Authors: LI Feng, LIN Haiyan, ZHU Chao, SHI Liming, SHANG Jinjie, CHEN Baoshan
PP: 1841-1849
Abstract: In this paper, three ribosomal protein (RP)-related genes RPS18, RPL30 and RPL32-B, whose expression are regulated by hypovirus infection, were knocked out respectively. However, only knockout mutants for RPL32-B were obtained. These mutants were heterozygous that could not be further purified to homozygous, demonstrating that these three RP genes were indispensable in Cryphonectria parasitica. An RNAi silencing recombinant plasmid pFCNH-intron-sll targeting RPS18, RPL30 and RPL32-B was developed and introduced into C. parasitica. Transformants showed significant reduction in virulence to chestnut stems, demonstrating that one or all of RPS18, RPL30 and RPL32-B was involved in virulence regulation in C. parasitica.
Keywords: phytopathology; Cryphonectria parasitica; ribosomal protein; gene knockout; multi-gene RNA silencing; virulence

Title: Transformation of green fluorescent protein gene in Fusarium oxysporum f. sp. cubense race 1 mediated by Agrobacterium tumefaciens

Authors: KONG Lingguang, HAN Kuande, JU Yanhu, DING Xinhua, CHU Zhaohui
PP: 1833-1840
Abstract: In this study, the Agrobacterium tumefaciens-mediated transformation system of Fusarium oxysporum f.sp. cubense (FOC) race 1 isolate was established successfully. Firstly, the DNA fragment of green fluorescent protein (GFP) was amplified by polymerase chain reaction (PCR). After digested with Cla〖KG-*2〗Ⅰ and SacⅡ, it was ligated into helper vector pUCATPH to replace the hygB gene, which results to construct the intermediate vector pUC-GFP. Then the pUC-GFP was digested with XbaI. And the DNA fragment carried GFP and promoter Ptrpc was inserted into fungi expression vector pBHT to form the expression construct pBHT-GFP. It was mobilized into LB4044 after several turns of proving with PCR, size filtration and sequencing. Furthermore, it was transformed into the race 1 isolate of F. oxysporum f. sp. cubense (FOC1) with Agrobacterium-mediated method. Transformants were regenerated and selected on hygromycin B containing medium. Strong green fluorescence could be observed in single-spore isolates after several successive generations on the medium without hygromycin B. The presence of the green fluorescent protein DNA in the fungal cells was also confirmed by PCR using a GFP-specific primer pair. The results showed that the ectogenous DNA had been stably integrated into the strain FOC1, without any observed difference on growth ability as wild isolate. They may lay a good foundation for studying the infection process and pathogenic mechanism of this pathogen.
Keywords: phytopathology; vector construction; Agrobacterium tumefaciens-mediated transformation; Fusarium oxysporum f. sp. cubense; green fluorescent protein

Title: Investigation of the wheat endosperm cell development

Authors: WANG Zhong, GU Yunjie, WANG Huihui, ZHENG Yankun, CHEN Yonghui, ZHANG Wenhu, WU Xiaomei
PP: 1815-1832
Abstract: Wheat Yangmai-5 was used as the experimental material in this paper. Development days of wheat caryopsis were marked exactly. The structures of transport systems and endosperm tissues and the development of endosperm cells were observed under light and electron microscopes. The results are as follows: 1) Endosperm epidermal cells can be differentiated into two types of cells. Those beside endosperm cavity are differentiated into the endosperm transfer cells and others are differentiated into the aleurone cells. 2) Endosperm cells have two types of amyloplasts. Large amyloplasts are formed during the early development stage while small amyloplasts are formed during the middle development stage (at about 16 days after pollination). Amyloplasts can proliferate by budding-type division or constriction-type division, et al. 3) The protein in endosperm cells is synthesized on the rough endoplasmic reticulum, transported by the Golgi apparatus, accumulates in vacuoles and becomes protein bodies. Small protein bodies can aggregate to form large protein bodies. 4) During the development of wheat inner endosperm cells, there are the occurrences of nucleus deformation, nucleus shift through the cell walls and nuclear degeneration. However, amyloplasts can still grow during the nuclear degeneration. 5) Caryopsis nutrient transport tissues mainly include the main vascular bundle, chalaza, nucellar projection transfer cells, endosperm transfer cells, aleurone cells and endosperm conducting cells. Nutrients unloaded by ventral vascular buddle must get through the apoplast before get into endosperm tissues.
Keywords: crop physiology; wheat; endosperm; endosperm transfer cells; aleurone cells; amyloplast; protein body

Title: Research on process and solubility of extruded cereal powder

Authors: XU Yacui, QIAN Haifeng, ZHANG Hui
PP: 1805-1814
Abstract: Corn, oats, ormosia, millet, rice, soybeans and barley were mixed in proportion of 0.10∶0.10∶0.15∶0.25∶0.10∶0.10∶0.20, the amino acid score (AAS) of the mixed cereal powder after double screw extrusion cooking achieved 71. Optimization of process variables during double screw extrusion cooking of mixed cereal powder was carried out using Box-Behnken experimental design, and the optimum parameters were obtained: terminal barrel temperature 106.3℃, heat-stable α-amylase concentration 20 U/g, screw rotating speed 102.5 r/min. Drying-matter solubility index (DSI) of mixed cereal powder achieved 33.11%, the agglomeration rate decreased to 0.80%. Mixed cereal powder after superfine comminution for 2 h, mean volume diameter was 38.375 μm, DSI achieved maximum 34.75%, the agglomeration rate achieved 0.75% and the powder color was acceptable since its ΔE was relatively small. It was appropriate for solubility when water temperature was 60~70℃, amount of water was 2~3 times of the powder. The DSI of the mixed cereal powder increased with spraying 0.1% gum Arabic, 0.1% CMC-Na or 0.1% monoglycerides, and the effect of the CMC-Na was particularly significant. Adding the amount of sucrose could significantly increase the DSI of mixed cereal powder, and with the increasing addition of sucrose, DSI increased.
Keywords: food processing technology; extruded cereal powder; amino acid score; solubility

Title: Sterilization effect of pressurized CO2 on major spoilage and pathogenic bacteria in milk

Authors: YAO Chunyan, LIU Meifeng, FU Ruidong, LI Xiaodong
PP: 1799-1804
Abstract: This paper stuided studied effect of pressurized CO2 on major spoilage (Pseudomonas fluorescent, Escherichia coli) and pathogenic bacteria (Staphylococcus aureus) in milk. The effects of CO2 pressure, treatment time, treatment temperature and treatment media on sterilization efficiency were investigated. The results indicated that the effect on three bacterium was increased by increasing pressure, treatment time and treatment temperature. Gram-negative bacteria were more sensitive than gram-positive bacteria to the treatment of pressurized CO2. When single bacterium was inoculated in sterilized milk, sterilizing ratio of pressurized CO2 were 99.09% for E. coli, 99.23% for P. fluorescent and 91.81% for S. aureus respectively, under 45℃, 6 MPa, 40 min. The bacterium was protected by milk protein and fat.
Keywords: dairy process technology; pressurized CO2; sterilization effects; milk; spoilage bacteria; pathogenic bacteria

Title: Effect of high hydrostatic pressure on microbial inactivation and inactivation kinetics analysis in cloudy apple juice

Authors: YI Jianyong, HU Xiaosong
PP: 1792-1798
Abstract: In order to explore the effects of high hydrostatic pressure (HHP) on microbial inactivation of fresh cloudy apple juice, aerobic bacteria, molds, yeasts and coliforms were investigated after HHP treatment at 300~600 MPa for 2.5~25 min and the kinetic analysis on the inactivation were carried out to guide the industrial production. The results showed that the effects of inactivation were improved with the pressure increasing and/or the holding time increasing. The molds, yeasts and coliforms were more sensitive to pressure treatment than aerobic bacteria, they were inactivated completely at 500 MPa and 300 MPa for 2.5 min, respectively. The Weibull model was used to analyze the survival curves. The coefficients of determination (R2) were all higher than 0.965, which proved that the Weibull model fitted the microbial inactivation kinetics curve well. Sterilization of cloudy apple juice could be achieved by HHP treatment at 600 MPa for 10 min. The results provided the technical basis for the application of HHP in commercial sterilization of cloudy apple juice.
Keywords: food technology and processing; high hydrostatic pressure; cloudy apple juice; microbial inactivation; processing parameters; Weibull model

Title: Formation mechanism and control method of ethyl carbamate in alcoholic beverages

Authors: ZHANG Xiuyan, CHEN Ziduan, CHEN Fusheng
PP: 1786-1791
Abstract: On the basis of introducing the characteristics and hazards of ethyl carbamate (EC), this paper summarizes the distribution, the tolerance limit in different beverage, the formation mechanism and the research progress on control method of EC in alcoholic beverage. This will provide academic reference for EC control in alcoholic beverage.
Keywords: food fermentation and brewing technique; ethyl carbamate; reviews; alcoholic beverages; formation mechanism; control method

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