Table of Content

15 May 2018, Volume 20 Issue 5

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Extraction of Anthocyanins from Purple Wheat and Its Effect on Antioxidant Activity and Inhibitory on Tumor Cells

YANG Sanwei1§, TIAN Peng2§, LI Liujun1, LU Dongtao3, QIAO Ling1, ZHAO Jiajia1, QIAO Linyi3, GE Chuan3, ZHENG Jun1*, ZHANG Jiancheng1*

2018, 20(5):  1-8.  DOI: 10.13304/j.nykjdb.2017.0471

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In order to provide an efficient method for extracting anthocyanins from purple wheat bran and understand its antioxidant and inhibitory effect on tumor cells, this experiment took the bran of purple wheat ‘Nongda 3753’ as material, extracted anthocyanin by the improved CTAB method and response surface methodology to optimize the extraction process. DMPD+ method was also used to measure the anthocyaninson antioxidant activity. HGC-27 and MGC-803 were used to determine the effect of anthocyaninson on tumor cells proliferation and invasion. The results indicated that the best process parameters of extraction were solid-liquid ratio 1 g∶3.2 mL, extraction time 1.1 h, extration number 3 times; and the yield was 3.40 g/kg. Antioxidant experiments showed that the antioxidant activity of anthocyanins was higher than that of water soluble vitamin E. Moreover, anthocyanins could inhibit the invasion and proliferation of gastric cancer cells HGC-27 and MGC-803. These results indicated that the improved CTAB extrcation method was easy to operate, and the anthocyanins extracted had higher purity and higher antioxidant activity and tumor inhibition effect.

Effects of Salt Stress on Root Morphology and Physiological Characteristics of Potted Cotton at Seedling Stage

WANG Qinghui1, YANG Jiapeng2, XIANG Guangrong3, LUO Jia3, HOU Yinying3, HAN Wei3, CHEN Bolang3*

2018, 20(5):  9-15.  DOI: 10.13304/j.nykjdb.2017.0349

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In order to discuss the impact of salt stress on photosynthesis and nutrient uptake of different cotton varieties at seedling stage and providing a theoretical basis for cotton cultivation management, salt tolerance mechanism and saline land improvement, this paper took salt sensitive cultivar (CCRI45) and salt tolerant cultivar (CCRI35) as materials, and conducted pot experiments to investigate the effect of salt stress on cotton photosynthesis character and nutrient adsorption. Results showed that salt stress significantly decreased the dry matter accumulation of cotton root, stem, leaf, whole plant and photosynthesis characteristic. Compared with the CK, the dry matter weight of whole cotton plant, net photosynthetic rate, stomatal conductance and transpiration rate decreased by 39.1%~40.1%, 33.9%~41.1%, 34.3%~36.6% and 27.7%~28.8%, respectively. The decreasing range of salt tolerant varieties was smaller than that of the salt sensitive varieties. The salt stress also significantly inhibited the adsorption and accumulation of N, K and P nutrients, and reduced the content of chlorophyll SPAD in cotton leaves. The decrease of net photosynthetic rate under salt stress was caused by no-stomatal restriction. Photosynthetic parameters and nutrient uptake were closely correlated with the resistance of genotype.

Influences of Fertilization on Soil Environment and  Microorganism in Continuous Cropping Based on  High-Throughput Sequencing

ZHANG Yijie, SHAO Huifang*, ZHANG Ke, JIA Hongfang, HUANG Wuxing, HAN Dan

2018, 20(5):  16-25.  DOI: 10.13304/j.nykjdb.2017.0348

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In order to study the effects of different fertilization treatments on soil environmental factors and microbial community diversity in continuous cropping tobacco plants, and understand the relationship between soil microbial community and environmental factors, this paper adopted IlluminaMiSeq high-throughput sequencing technique to sequence bacteria 16S rRNAV4-V5 district and fungi ITS rRNAV4-V5 district in soil of continuous cropping tobacco plants under different fertilization treatments and studied the relationship between 8 environmental factors(organic matter, available nitrogen, available phosphorus, available K, protease, catalase, phosphatase, sucrase ) and the microbes by principal component analysis and redundancy analysis. The results showed that after sequencing, 264 500 effective sequences and 22 035 operation classification units (OTUs) were obtained. Colonies showed that the fertilization treatment increased the community composition of bacteria and fungi in the soil compared with that of the contrast. There were bigger differences in bacterial and fungal diversity between fertilization treatment and the CK. The results showed that fertilization could significantly change the structure of bacteria and fungi in soil. The content of available K could affect the diversity and abundance of soil bacterial community in a certain range, and the 8 environmental factors could affect the diversity and abundance of fungi by different degree. The soil microbial information of tobacco rhizosphere obtained by high-throughput sequencing technology was rich, and provided theoretical references for different fertilization treatments affecting soil environmental factors and microbial community diversity.


Glucose-Tolerance Molecular Modification of GH1 β-glucosidase from Alicyclobacillus sp. A4

CAO Huifang, LI Xinxin, ZHANG Yueqi, SHI Pengjun, BAI Yingguo*, YAO Bin*

2018, 20(5):  26-33.  DOI: 10.13304/j.nykjdb.2017.0350

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Soybean isoflavones has the effect of promoting growth and accelerating protein synthesis, but it mainly exists in the soybean meal with inactive and bounded form. In the feed field based on corn and soybean meal, β-glucosidase could convert the bounded soybean isoflavones into the free and active aglycone, but the transformation process was inhibited by the relatively high concentration of glucose in the intestinal tract. Compared with the GH3 family, β-glucosidase from GH1 family has not only higher glucose tolerance, but also can be stimulated by glucose with a certain range of concentration. Hence, it shows great potential for application in the field of feed. This study cloned and expressed a GH1 family β-glucosidase AsBG1 from Alicyclobacillus sp. A4 with high glucose tolerance (IC50 800 mmol/L). In order to further improve the glucose tolerance of AsBG1, the molecular mutation of AsBG1 was conducted focusing on the non-active binding sites of glucose in catalytic channel and based on homology modeling, sequence alignment and molecular docking. The glucose tolerance test showed that with 5 mmol/L pNPG as substrate, the specific activity of WT, H315R and M325K was stimulated to 125%, 163% and 162% by 100 mmol/L glucose, respectively. And the IC50 of H315R increased to 1 200 mmol/L. With 1 mmol/L daidzin as substrate, the activity of WT, H315R and M325K was stimulated to 163%, 212% and 226% by 10 mmol/L glucose, respectively. This study  enriched the understanding of glucose tolerance mechanism of GH1 family and had important guiding significance for the relevant molecular modification of tolerance in the future.


Research  Progress on Molecular Biology  of β-mannanases

ZHANG Rui, ZHU Hong, ZHOU Junpei, HUANG Zunxi*

2018, 20(5):  34-46.  DOI: 10.13304/j.nykjdb.2017.0798

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Endo-β-mannanase is widely applied in various industries including food, feed, paper making and lavation. Recently, with the overflying development of gene sequencing technology, many novel endo-β-mannanases have been unearthed and their enzymatic properties have been investigated in recent year. The paper introduced various types of mannan and its degrading enzymes; summarized classification, sources, structures and catalytic mechanisms of endo-β-mannanases; and summarized the recombination expression, enzymatic properties and molecular modification of endo-β-mannanases sourced from microorganisms in recent years. Furthermore, the paper briefly described the application of endo-β-mannanases in food and feed industries and prospected the research hotspot and direction of endo-β-mannanase.


Research Advance on β-aminobutyric Acidinduced to Stress Resistance In Tobacco

MA Xiaohan1, GONG Zhixiang1, WANG Lin1, YANG Lijun2, HUANG Haitang2, XU Zicheng1*

2018, 20(5):  47-53.  DOI: 10.13304/j.nykjdb.2017.0234

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β-aminobutyric acid (BABA) is a nonprotein amino acid in tobacco proceeding broad-spectrum resistance. It has significant effection against various biotic and abiotic stresses. This paper introduced the research achievements and application of BABA in plant, summarized the mechanism of BABA in induceding tobacco resistance, analyzed its effect against tobacco resistance, and prospected the application of BABA on tobacco industry.

Structure Optimization and Experiment on Cyclone Separation-Purification Device for Small Rice Combine Harvester

XIE Chao1, LIU Dawei1,2, LI Xu1,2, XIE Fangping1,2*, WANG Xunwei1, XIE Jinfan1

2018, 20(5):  54-63.  DOI: 10.13304/j.nykjdb.2017.0822

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Cyclone cleaning device has  small size, light weight and simple structure, etc. merits and has been widely used in small rice combine harvester. But there are problems like high loss rate, no ideal cleaning effect when choosing wet material in selection process, etc.. This paper further optimized and improved the inside structure of cycrong seperator; and carried out comparative analysis on the airflow field inside of scycrong seperator before and after optimization by software Fluent 15.0. Taking suction rotation rate, grain winnower rotation rate and baffle inclination angle as experimental factors, and cleaning ratio and loss rate as evaluated index, this paper operated a bench test by ternary quadratic orthogonal test method. The results indicated that when the suction rotation rate was 2 452 r/min, winnower rotation rate was 783.8 r/min and the baffle inclination angle was 41°, the device showed the best efficiency. Then the cleaning rate of the machine was 98.26%, the cleaning loss rate was 0.003 5%. The results of the controlled trial indicated that the higher rate of water content the device had, the better performance it would get. These results provided references for the optimal design of cyclone cylinder structure in the later period.

Detection of Young Green Apples for Fruit Robot in Natural Scene

XIA Xue1, ZHOU Guomin1*, QIU Yun1, LI Zhuang2, WANG Jian1, HU Lin1, CUI Yunpeng1, GUO Xiuming1

2018, 20(5):  64-74.  DOI: 10.13304/j.nykjdb.2017.0372

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In order to realize  automatically managing fruit production by robot during young fruit period, this paper took young green apples in orchard as object and studied the detection method of young green apples by machine under natural environment. Firstly, adaptive green and blue chromatic aberration (AGBCA) map was designed and combined with the iterative threshold segmentation (ITS) algorithm  to detect region of interest (ROI) contained potential apple fruits pixels. Then, potential fruits were identified by an improved circular hough transformation (CHT) after morphological operation and Blob analysis of the results obtained from AGBCA and ITS, which kept  many potential apple fruits pixels as possible. Finally, a kernel support vector machine(SVM) classifier, optimized by grid search optimal algorithm, was built to remove false fruit objects based on histogram of oriented gradient(HOG) feature descriptor. The experimental results showed that the true positive rate of proposed method was 88.51%, false negative rate and false positive rate were 11.49% and 4.84%, respectively. And the F1-Measure of proposed model was 90.29%, indicating the proposed method had better detection ability and robustness for young green apples detection. The results provided references to fruit robot for automatic detection during young fruit stage.

Study on the Harvesting Posture of the Citrus Harvesting Robot Based on Occlusal End-effector

ZHANG Zhe1, WANG Yi1,2*, FU Shun1, MA Jitong1

2018, 20(5):  75-82.  DOI: 10.13304/j.nykjdb.2017.0398

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In order to resolve the problem that the harvesting robot vision system is not able to acurately provide the growth posture of citrus fruit under complex natural environment, thus the successful rate of harvesting is reduced, this paper proposed an optimum harvesting posture determination method based on citrus harvesting robot occlusal end-effector. This method based on end-effector configuration parameters, established the performance evaluation function of the harvesting posture to the center position of fruit, and gained the optimal harvesting posture of actuator by using calculation of this function. The calculated optimal harvesting posture was verified by constructing harvest experiment platform and designing harvest experiment. The results showed that citrus harvesting successful rate was increased by 26.32% using the harvesting posture optimized by the optimal harvesting posture evaluation method, compared with the general horizontal harvesting posture.

Evaluation on Selenium Biofortification Potential of Commercial Wheat Cultivars in Middle and Lower Reaches of the Yangtze River

SUN Fayu1, CHEN Xin1, MA Qichuang1, LI Lei1, WU Hongya2, LI Tao1*

2018, 20(5):  83-90.  DOI: 10.13304/j.nykjdb.2017.0386

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In order to select ideal varieties suitable for follage spraying selenium (Se) biofortification in grains of different wheat cultivars in Middle and Lower Reaches of the Yangtze River, 300 mg Se/L（Se300） foliar fertilizer was sprayed uniformly onto 63 wheat cultivars during booting-heading stages. The contents of Se, Cu, Fe, Mn, Zn, Ca, K, Mg, P and S were measured using ICP. The results indicated that follage spraying selenate increased significantly Se content in wheat grains. The average value of total Se content increased 2.13±0.73 mg/kg to 9.13±3.86 mg/kg then contrast, but the amplification varied among cultivars. Different mineral elements in grains responded differently to follage spraying selenate, decreasing the contents of Cu, Fe, K, Mg, and S in grains, but increasing Zn contents, and having no effect on Mn and Ca contents. Comprehensive comparison showed that ‘Jiangmai 816’ was one of the cultivars mainly popularized in Middle and Lower Reaches of the Yangtze River with larger Se biofortification potential.

Effect of Reducing Fertilizer Application Models on Crop Yield and Nutrient Use Efficiencies in Rice-wheat Cropping System

LIU Wei1,2, XIONG Yousheng1*, XU Xiangyu1, HUANG Xiurong3, HE Wenjie4, ZHOU Jianxiong1, YUAN Jiafu1

2018, 20(5):  91-99.  DOI: 10.13304/j.nykjdb.2017.0786

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In order to explore the effects of different reducing fertilizer application modes on crop yield, nutrient use efficiency in rice-wheat cropping system and to provide theoretical basis for achieving high efficient application of chemical fertilizer and its zero increase in China, this paper carried out one-year 2 crops field experiment of rice-wheat cropping system. The experiment set 6 treatments including no fertilizer (CK), conventional chemical fertilization (CF), combined application of organic manure and chemical fertilizer (LF1), reducing 20% chemical fertilizer plus increasing nitrogen fertilizer synergist application (LF2), reducing 20% chemical phosphorus fertilizer along with phosphorus activator application(LF3), and reducing 20% chemical nitrogen fertilizer and 20% chemical phosphorus fertilizer along with nitrogen fertilizer synergist plus phosphorus activator application (LF4). The results indicated that compared with conventional fertilizer(CF), rice and wheat yield of LF2 treatment increased significantly by 7.6%, that of LF4 treatment decresed by 6.2%. The LF1 and LF3 treatments had no obvious effect on rice and wheat yield. The LF2 treatment could significantly increase the partial fertilizer productivity of nitrogen, phosphorus, and potassium and uptaking efficiency of nitrogen and phosphorus. The LF4 treatment could significantly increase nitrogen and phosphorus partial factor productivity (NPFP), and the uptake efficiency (NUPE) of nitrogen and phosphorus, and significantly reduce potassium partial factor productivity (PPFP). The LF1 treatment could significantly increase only the nitrogen use efficiency (NUE), whereas the LF3 treatment had no significant effect on N, P, K nutrient use efficiency. In conclusion, the LF2 treatment was in favour of coordinating crop nutrient uptake and increase yield. It could be a preferent pattern for reducing fertilizer application and increasing efficiency in rice-wheat cropping system at the Middle and Lower Reaches of the Yangtze River and areas with similar ecological conditions.

Yield Comparisons and Phenotypic Evaluations of Varieties for Foxtail Millet [Setaria italica (L.) P. Beauv.]  with Different Sources

XU Feng1, SUO Liangxi1, MENG Hailong2, LI Guihong1, CHENG Kai2, ZHANG Jiale2,

2018, 20(5):  100-110.  DOI: 10.13304/j.nykjdb.2017.0881

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Aohan County of Chifeng City in Inner Mongolia is the largest production base of high-quality foxtail millet in China. This paper carried out field planting identification on 115 foxtail millet varieties (lines) and analyzed the yield phenotypic traits. The results showed that the yields of 31 varieties (lines) were higher than that of the CK(Chigu 4). The growth period of these varieties (lines) was 106.16±5.71 d, their length of main stem was 133.97±14.85 cm, main panicle length was 27.32±4.02 cm, main panicle diameter was 29.18±5.89 mm, main panicle weight was 29.10±5.63 g, seed numbers in main panicle were 8 333.99±1 983.66, main panicle grain weight was 22.91±4.69 g, 1 000-grain weight was 2.80±0.36 g, and their yields were 7 887.41±796.60 kg/hm2. The results of variance analysis showed that the yields of 25 varieties (lines) were significantly higher than that of the CK (P<0.01), grain number and 1 000-grain weight  per panicle were significantly increased, or yield traits were synergistic improved and higher yield increase could be realized. The result of correlation and regression analysis showed that the growth period, length and diameter of main stem, number of leaf, main panicle weight, main panicle grain number and weight, and 1 000-grain weight were significantly correlated with the yield. Among them the growth period and main panicle grain number played decisive roles on yield. Principal component analysis concluded 15 phenotypic traits into 8 main vectors, and 10 varieties (lines) with higher comprehensive eveluation were selected. On the whole, the yield of Yangu 18 was the highest. The yield and comprehensive eveluation of Tie 8050, Gonggu 74, 14H758 were higher than that of the other varieties (lines).

Soybean Canopy Radiation Interception and Its Influence on Yield Production in Extremely Precocious Area

GENG Jinjian, WANG Chunyan*, CHENG Wanying, YANG Xueling, LI Maosong

2018, 20(5):  111-123.  DOI: 10.13304/j.nykjdb.2017.0320

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The local soybean cultivar (Heihe 43) was grown under mulching film and different planting density and chemical control in Jiusanguanliju of Heihe in Heilongjiang in 2015 and 2016. The daily meteorological elements data including temperature, precipitation and insolation duration were collected from 1987-2016 of Nenjiang, Heihe, Heilongjiang, China. Leaf area was measured with an automatic area meter. At pod filling stage, the ten leaves of each layer every 10 cm were chosen for measuring the intercepted radiation with simple integrated solarimeter films. The radiation interception per unit leaf area (IRL), the radiation interception per unit ground area (IRG), the amount of radiation interception of each leaf, LAI (leaf area index) and accumulated radiation interception of layer every 10 cm were calculated. The results showed that the yield in 2015 increased because of more rain, while the drought stress at July-August 2016 seriously affected plant growth and development, the LAI and radiation interception were low, and this leaded to production decrease. The distribution of light within the canopy was linear change, mainly in soybean canopy on top. IRG had highly significant positive correlations to IRL, leaf number, LAI, leaf area, indicating that the canopy structure was a important factor to canopy radiation, the IRL became bigger with the LAI increase. Soybean hundred grain weight and yield were highly positively correlated with IRL, indicated  canopy radiation had important effect on growth and yield of soybean. The mulching film and D2 density (48×104 panicle/hm2) treatment were highest in canopy radiation and yield production. So higher density with mulching film and chemical regulator affected the canopy structure, getting higher LAI and making full use of climatic resources especially the water and radiation interception were important measures to improving the dry matter and yield production.

Effects of Fertilization on Selenium Content, Nutrient and Quality of Tea in Se-enriched Tea Garden

YANG Haibin, LI Zhonglin, XU Ze, DENG Min*, SHENG Zhonglei

2018, 20(5):  124-131.  DOI: 10.13304/j.nykjdb.2017.0366

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In order to provide efficient, high quality and safe fertilization to se-enriched tea producing areas, this paper studied the effects of applying organic fertilizer combined with phosphorus and potassium fertilizer(O1-O6), urea combined with phosphorus and potassium fertilizer(UI-U6); single application of organic fertilizer(O7,O8), and urea(U7,U8) on tea selenium content, nutrient and quality in se-enriched garden by field experiment. The results showed that the organic selenium content in spring and summer tea leaves were increased obviously by different fertilization, and the content of organic selenium in spring tea leaves was higher than that of summer tea leaves. The content of organic selenium was high by treatment of organic fertilizer application and improvement in tea leaves of both seasons was the most obvious in O6 treatment, and the contents were 0.158 mg/kg  and 0.116 mg/kg, respectively, which were increased by 62.12% and 67.32% compared with that by conventional fertilization. The overall performance of nitrogen, phosphorus, potassium content was spring tea>summer tea, nitrogen, phosphorus, potassium contents in spring tea were the highest in O6 treatment, increased by 22.34%, 59.18% and 17.36% compared with that of the conventional fertilization, respectively. Spring tea quality was improved obviously by combined application of organic fertilizer; and summer tea quality was improved obviously by different fertilization treatments. The overall performance of tea phenol ammonia ratio was spring tea＜summer tea, spring tea phenol ammonia ratio was the least in O6 treatment, reduced by 15.60% compared with that by conventional fertilization. Regression analysis showed that application of phosphate fertilizer in spring had significant effect on spring tea organic selenium content, application of nitrogen fertilizer in spring and summer had significant effect on summer tea organic selenium content.

Influences of Flocculation on Wastewater with High Concentration Pollutants from Dairy Cattle Farm

YANG Peiyuan1, SHANG Bin1, WEN Fuyong2, ZHAO Haiming2, TAO Xiuping1*, DONG Hongmin1, LU Yongqiang3, WANG Jun3

2018, 20(5):  132-139.  DOI: 10.13304/j.nykjdb.2017.0755

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Since the wastewater from dairy farms contains high concentration of organics, wastewater must be treated to meet the requirements of related discharge standards. In order to reduce environment pollution caused by wastewater from dairy farms located at the suburb of Beijing, this paper designed a pretreatment experiment at bench-scale to optimize the operational parameters of chemical flocculation. Poly aluminum chloride (PAC) and 3 types of ionic polyacrylamide (PAM) were used as flocculants, and 2 flocculation trials were conducted and compared. The results showed that the effect of PAM was better than that of PAC and PAM combination. As for PAM adding, the ionic types of PAM took a role in the flocculation effects (P＜0.05). The best flocculation effect was observed in adding 2.5 mL NPAM at the dosage of 1 g/L. In such case, the concentrations of COD, NH+4-N and total phosphorus in supernatant were (12 892±2 354) mg/L, (462±53) mg/L and (31±3) mg/L, and the removal rates were 69.48%±4.10%, 13.11%±8.59% and 85.05%±1.27%, respectively. Moreover, it cost only 0.05 yuan/m3. Therefore, it was feasible to pretreat the dairy farm wastewater with non-ionic polyacrylamide, thus easily reducing organics and suspending solid in the wastewater. This study  provided a scientific basis for the application of flocculation on wastewater with high concentration pollutants from dairy cattle farm.


Study on the Bacteriostasis of ZnO Micro/Nano-particles with Different Morphologies on Foodborne Pathogens

LIU Huiying1,2, QIAO Yu1, SHI Bo1, PENG Qing1*

2018, 20(5):  140-147.  DOI: 10.13304/j.nykjdb.2017.0431

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Foodborne pathogens inducing foodborne diseases are the main factors of food safety. Having favourable bacteriostasis, ZnO has a wide application prospect as antibacterial material. This study prepared and obtained 4 morphology types of ZnO micro/nano-particles with rodlike, fusiform, hollow spherical and cellular, and tested their bacteriostasis with 8 common foodborne pathogens by inhibition zone method and growth curve method. The results showed that ZnO had different bacteriostasis on different foodborne pathogens, and the bacteriostasis was closely related to its morphology. The above results provided valuable basic data for the development and application of ZnO micro/nanoantimicrobial materials.

Research on Preparation Technology of Polylactic Acid Nano-microsphere

SUN Changjiao, WANG Yan, ZHAO Xiang, CUI Bo, ZENG Zhanghua, CUI Haixin*

2018, 20(5):  148-153.  DOI: 10.13304/j.nykjdb.2017.0373

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Polylactic acid (PLA) has been widely used in the medical field，because of its good bio-compatibility and bio-degradablity. The preparation of pesticide delivery system with PLA as carrier can effectively prevent the degradation of sensitive drugs and prolong the duration of pesticide. This experiment prepared poly lactic acid nano-microspheres by emulsion solvent evaporation method (O/W); investigated the effects of surfactant kind and concentration, volume ratio of  organic phase to aqueous phase, concentration of PLA, etc. factors on the size of nano-microsphere; characterized its morphology by scanning electron microscopy and transmission electron microscopy; and also characterized the particle size and polydispersity index by particle size analyzer. The results indicated that choosing Tween20 as surfactant, when Tween20 concentration was 0.01~0.03 g/mL, PLA concentration was 0.02 g/mL and ratio of V(oil phase)∶V(aqueous phase) = 1∶10, the nano-microsphere with 230~250 nm particle size could be prepared by ultrasonic emulsification. These nano-microspheres had better dispersibility and spheronization. The PLA-azoxystrobin nano-microspheres were further prepared. The results showed that the surfactant concentration was a key factor affecting the particle size. When the concentration of Tween20 was 0.03 g/mL, nano-microspheres with 236 nm particle size could be obtained. The entrapment efficiency and drug-loading rate were 81.38% and 27.11%, respectively. This study provided technical and parameter support for the preparation of environmental-friendly PLA sustainable release nano-microspheres for pesticide.