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Mycorrhizoremediation—an enhanced form of phytoremediation
KHAN Abdul G.
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 1-.   https://doi.org/10.1631/jzus.2006.B0503
Abstract( 2735 )     PDF(0KB)( 1157 )
Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere microflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial biotechnology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation.
Prediction of the P-leaching potential of arable soils in areas with high livestock densities
WERNER Wilfried, TRIMBORN Manfred, PIHL Uwe
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 2-.   https://doi.org/10.1631/jzus.2006.B0515
Abstract( 2398 )     PDF(0KB)( 1087 )
Due to long-term positive P-balances many surface soils in areas with high livestock density in Germany are oversupplied with available P, creating a potential for vertical P losses by leaching. In extensive studies to characterize the endangering of ground water to P pollution by chemical soil parameters it is shown that the available P content and the P concentration of the soil solution in the deeper soil layers, as indicators of the P-leaching potential, cannot be satisfactorily predicted from the available P content of the topsoils. The P equilibrium concentration in the soil solution directly above ground water table or the pipe drainage system highly depends on the relative saturation of the P-sorption capacity in this layer. A saturation index of <20% normally corresponds with P equilibrium concentrations of <0.2 mg P/L. Phytoremediation may reduce the P leaching potential of P-enriched soils only over a very long period.
In-situ nitrogen removal from the eutrophic water by microbial-plant integrated system
CHANG Hui-qing, YANG Xiao-e, FANG Yun-ying, PU Pei-min, LI Zheng-kui, RENGEL Zed
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 3-.   https://doi.org/10.1631/jzus.2006.B0521
Abstract( 2419 )     PDF(0KB)( 1166 )
Objective: This study was to assess the influence of interaction of combination of immobilized nitrogen cycling bacteria (INCB) with aquatic macrophytes on nitrogen removal from the eutrophic waterbody, and to get insight into different mechanisms involved in nitrogen removal. Methods: The aquatic macrophytes used include Eichhornia crassipes (summer-autumn floating macrophyte), Elodea nuttallii (winter-growing submerged macrophyte), and nitrogen cycling bacteria including ammonifying, nitrosating, nitrifying and denitrifying bacteria isolated from Taihu Lake. The immobilization carriers materials were made from hydrophilic monomers 2-hydroxyethyl acrylate (HEA) and hydrophobic 2-hydroxyethyl methylacrylate (HEMA). Two experiments were conducted to evaluate the roles of macrophytes combined with INCB on nitrogen removal from eutrophic water during different seasons. Results: Eichhornia crassipes and Elodea nuttallii had different potentials in purification of eutrophic water. Floating macrophyte+bacteria (INCB) performed best in improving water quality (during the first experiment) and decreased total nitrogen (TN) by 70.2%, nitrite and ammonium by 92.2% and 50.9%, respectively, during the experimental period, when water transparency increased from 0.5 m to 1.8 m. When INCB was inoculated into the floating macrophyte system, the populations of nitrosating, nitrifying, and denitrifying bacteria increased by 1 to 2 orders of magnitude compared to the un-inoculated treatments, but ammonifying bacteria showed no obvious difference between different treatments. Lower values of chlorophyll a, CODMn, and pH were found in the microbial-plant integrated system, as compared to the control. Highest reduction in N was noted during the treatment with submerged macrophyte+INCB, being 26.1% for TN, 85.2% for nitrite, and 85.2% for ammonium at the end of 2nd experiment. And in the treatment, the populations of ammonifying, nitrosating, nitrifying, and denitrifying bacteria increased by 1 to 3 orders of magnitude, as compared to the un-inoculated treatments. Similar to the first experiment, higher water transparency and lower values of chlorophyll a, CODMn and pH were observed in the plant+ INCB integrated system, as compared to other treatments. These results indicated that plant-microbe interaction showed beneficial effects on N removal from the eutrophic waterbody.
Characterization of on-road CO, HC and NO emissions for petrol vehicle fleet in China city
GUO Hui, ZHANG Qing-yu, SHI Yao, WANG Da-hui, DING Shu-ying, YAN Sha-sha
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 4-.   https://doi.org/10.1631/jzus.2006.B0532
Abstract( 2676 )     PDF(0KB)( 1046 )
Vehicle emissions are a major source of air pollution in urban areas. The impact on urban air quality could be reduced if the trends of vehicle emissions are well understood. In the present study, the real-world emissions of vehicles were measured using a remote sensing system at five sites in Hangzhou, China from February 2004 to August 2005. More than 48000 valid gasoline powered vehicle emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO) were measured. The results show that petrol vehicle fleet in Hangzhou has considerably high CO emissions, with the average emission concentration of 2.71%±0.02%, while HC and NO emissions are relatively lower, with the average emission concentration of (153.72±1.16)×10−6 and (233.53±1.80)×10−6, respectively. Quintile analysis of both average emission concentration and total amount emissions by model year suggests that in-use emission differences between well maintained and badly maintained vehicles are larger than the age-dependent deterioration of emissions. In addition, relatively new high polluting vehicles are the greatest contributors to fleet emissions with, for example, 46.55% of carbon monoxide fleet emissions being produced by the top quintile high emitting vehicles from model years 2000~2004. Therefore, fleet emissions could be significantly reduced if new highly polluting vehicles were subject to effective emissions testing followed by appropriate remedial action.
Quantitative estimation of dust fall and smoke particles in Quetta Valley
SAMI Muhammad, WASEEM Amir, AKBAR Sher
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 5-.   https://doi.org/10.1631/jzus.2006.B0542
Abstract( 2562 )     PDF(0KB)( 1284 )
Tightening of air quality standards for populated urban areas has led to increasing attention to assessment of air quality management areas, where violation of air quality standards occurs, and development of control strategies to eliminate such violation of air quality standards. The Quetta urban area is very densely built and has heavy motorized traffic. The increase of emissions mainly from traffic and industry are responsible for the increase in atmospheric pollution levels during the last years. The dust examined in the current study was collected by both deposit gauge and Petri dish methods at various sites of Quetta Valley. Smoke particles were obtained by bladder method from the exhausts of various types of motor vehicles. The concentration of lead found in the smoke ranged from 1.5×10−6 to 4.5×10−6.
Structure relationship of nitrochlorobenzene catalytic degradation process in water over palladium-iron bimetallic catalyst
NIU Shao-feng, ZHOU Hong-yi, AO Xu-ping, XU Xin-hua, LOU Zhang-hua
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 6-.   https://doi.org/10.1631/jzus.2006.B0548
Abstract( 2208 )     PDF(0KB)( 924 )
Two isomers of nitrochlorobenzene (o-, and p-NCB) were treated by a Pd/Fe catalyst in aqueous solutions through catalytic amination and dechlorination. Nitrochlorobenzenes are rapidly converted to form chloroanilines (CAN) first through an amination process, and then rapidly dechlorinated to become aniline (AN) and Cl, without the involvement of any other intermediate reaction products. The amination and dechlorination reaction are believed to take place predominantly on the surface site of the Pd/Fe catalysts. The dechlorination rate of the reductive degradation of the two isomers of nitrochlorobenzene (o-, and p-NCB) in the presence of Pd/Fe as a catalyst was measured experimentally. In all cases, the reaction rate constants were found to increase with the decrease in the Gibbs free energy (correlation with the activation energy) of NCBs formation; the activation energy of each dechlorination reaction was measured to be 95.83 and 77.05 kJ/mol, respectively for o- and p-NCB. The results demonstrated that p-NCBs were reduced more easily than o-NCBs.
Preparation of SO42–/TiO2-La2O3 solid superacid and its catalytic activities in acetalation and ketalation
YANG Shui-jin, BAI Ai-min, SUN Ju-tang
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 7-.   https://doi.org/10.1631/jzus.2006.B0553
Abstract( 2487 )     PDF(0KB)( 1121 )
SO42–/TiO2-La2O3, a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n(La3+):n(Ti4+) is 1:34, the soaked consistency of H2SO4 is 0.8 mol/L, the soaked time of H2SO4 is 24 h, the calcining temperature is 480 °C, the calcining time is 3 h. Then it was applied in the catalytic synthesis of ten important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is 1:1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%~95.8%.
Separation of phosphatidylcholine from soybean phospholipids by simulated moving bed
LÜ Yu-bin, YANG Yi-wen, WU Ping-dong
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 8-.   https://doi.org/10.1631/jzus.2006.B0559
Abstract( 2352 )     PDF(0KB)( 1048 )
A simulated moving bed (SMB), equipped with eight silica-gel columns, was used to separate phosphatidylcholine (PC) from soybean phospholipids. The effects of flow rate in Sections 2 (Q2) and 3 (Q3), switching time, feed flow rate and feed concentration on the operating performance parameters: purity, recovery, productivity and desorbent consumption were studied. Operating conditions leading to more than 90% purity in both outlet streams have been identified, together with those achieving optimal performance. Regions leading to complete separation are observed and explained theoretically. As the mass-transfer effect was not considered, the triangle theory only gives initial guesses for the optimal operating conditions.
Genotypic and environmental variation in cadmium, chromium, arsenic, nickel, and lead concentrations in rice grains
CHENG Wang-da, ZHANG Guo-ping, YAO Hai-gen, WU Wei, XU Min
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 9-.   https://doi.org/10.1631/jzus.2006.B0565
Abstract( 2601 )     PDF(0KB)( 1123 )
Genotypic and environmental variation in Cd, Cr, As, Ni and Pb concentrations of grains, and the relationships between these heavy metals and Fe, Zn were investigated using 9 rice genotypes grown in 6 locations for two successive years. Significant genotypic variation was detected in the five heavy metal concentrations in grains, indicating the possibility to reduce the concentration of these heavy metals in grains through breeding approach. The environmental effect varied with metal, with Pb and Ni having greater variation than the other three metals. There was significant genotype-environment (location) interaction of the concentrations of all five heavy metals in grains, suggesting the importance of cultivar choice in producing rice with low heavy metal concentrations in grains for a given location. Correlation analysis showed that Cd and As, Cr and Ni, and As and Pb concentrations in rice grains were closely associated, and that Ni concentration in grains was negatively correlated with Zn concentration.
Growth and yield of rice as affected by transplanting dates and seedlings per hill under high temperature of Dera Ismail Khan, Pakistan
BALOCH Mohammad Safdar, AWAN Inayat Ullah, HASSAN Gul
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 10-.   https://doi.org/10.1631/jzus.2006.B0572
Abstract( 2662 )     PDF(0KB)( 1133 )
Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill−1 on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pakistan. The experiment was laid out in a randomized complete block design with split plot arrangements. Main plots consisted of four transplanting dates viz. 20th and 27th of June and 4th and 11th of July while sub-plots contained 1, 2, 3 or 4 seedlings hill−1. Among transplanting dates, June 20th planted crop gave highest paddy yield and net return with 1 seedling hill–1. It explains that the use of more seedlings hill−1 not only adds to cost but is also a mere wastage of natural resources. Based on research findings, we conclude that the use of 1 seedling hill−1 is most appropriate for timely sowing otherwise 4 seedlings hill–1 should be used to compensate for the yield gap in late transplanted rice.
Effects of ration level and feeding frequency on digestibility in juvenile soft-shelled turtle, Pelodiscus sinensis
LEI Si-jia
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 11-.   https://doi.org/10.1631/jzus.2006.B0580
Abstract( 2300 )     PDF(0KB)( 1202 )
The effects of ration level and feeding frequency on digestibility in juvenile soft-shelled turtle, Pelodiscus sinensis, were investigated. Four ration levels 1.5%, 2.5%, 4.0% and satiation (6.0% BW/d) were used. Apparent digestibility (AD) of dry matter (DMAD), protein (PAD) and protein real digestibility (PRD) were significantly affected by ration level, but not by feeding frequency when the ration level was similar. However, the feeding frequency affected the AD, DMAD, PAD and PRD significantly when the turtles were fed to satiation. The relationship between fecal protein content (Y) and protein intake (X) can be expressed as a quadric equation: Y=−0.1742+0.1476X−0.0003X2 (r2=0.876, n=27, F=93.92, P<0.01).
Characteristics of transgenic tomatoes antisensed for the ethylene receptor genes LeERT1 and LeERT2
WANG Zhong-feng, YING Tie-jin, ZHANG Ying, BAO Bi-li, HUANG Xiao-dan
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 13-.   https://doi.org/10.1631/jzus.2006.B0591
Abstract( 2286 )     PDF(0KB)( 1021 )
Two stable transformed lines containing antisense LeERT1 or LeERT2 sequences and their hybridized line were investigated to determine the effect of LeERT1 and LeERT2 specificity in the ethylene receptor family in tomato (Lycopersicon esculentum Mill.) on ethylene signaling. The transgenic line ale1 containing antisense LeERT1 displayed shorter length of seedling grown in the dark and adult plant in the light, severe epinastic petiole, and accelerated abscission of petiole explant and senescence of flower explant, compared with its wild type B1. The transgenic line ale2 containing antisense LeERT2 also exhibited shorter hypocotyls and slightly accelerated abscission. The phenotypes of cross line dale of LeERT1 and LeERT2 were close to ale1 in many aspects. These results suggested that LeERT1 probably plays a relatively important role in ethylene signaling of tomato growth and development.
Effects of dietary supplementation with Clostridium butyricum on the growth performance and humoral immune response in Miichthys miiuy
SONG Zeng-fu, WU Tian-xing, CAI Li-sheng, ZHANG Li-jing, ZHENG Xiao-dong
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 14-.   https://doi.org/10.1631/jzus.2006.B0596
Abstract( 2452 )     PDF(0KB)( 1485 )
The effects of dietary supplementation with Clostridium butyricum on growth performance and humoral immune response in Miichthys miiuy were evaluated. One hundred and fifty Miichthys miiuy weighing approximately 200~260 g were divided into five groups and reared in 15 tanks with closed circuiting culture system. The animals were fed 5 diets: basal diet only (control) or supplemented of the basal diet with C. butyricum at doses of 103 (CB1), 105 (CB2), 107 (CB3) or 109 (CB4) CFU/g. Compared with the control, the serum phenoloxidase activity was significantly increased by the supplementation (P<0.05), acid phosphatases activity was increased significantly (P<0.05) at the doses of 109 CFU/g. Serum lysozyme activity peaked at dose of 107 CFU/g and in the skin mucus at dose of 109 CFU/g. Immunoglobulin M level in the serum and skin mucus was increased except at dose of 103 CFU/g (P<0.05). The growth at the dose of 109 CFU/g was higher than that of the control (P<0.05). It is concluded that supplementation of C. butyricum can mediate the humoral immune responses and improve the growth performance in Miichthys miiuy.
Biotechnological Engineering
Studies on characteristics of nanostructure of N-TiO2 thin films and photo-bactericidal action
XU Ming-fang, LIN Shan, CHEN Xin-man, PENG Yan-zhi
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2006, 7(7): 586-590.   https://doi.org/10.1631/jzus.2006.B0586
Abstract( 2593 )     PDF(0KB)( 904 )
Pseudomonas aeruginosa strain (AS1.50) and Bacillus subtilis strain (AS1.439) from Ming lake were decomposed by photocatalytic nanostructure N-TiO2 thin films in a photo-reactor under UV irradiation. The different thickness nanostructure N-TiO2 thin films coated on mesh grid were prepared by sol-gel method and immobilized at 500 °C (films A) or 350 °C (films B) for 1 h in a muffle furnace. The results showed that N-TiO2 thin film B (8.18 nm thickness, 2.760 nm height and 25.15 nm diameter) has more uniform granular nanostructure and thinner flat texture than N-TiO2 thin film A (12.17 nm thickness, 3.578 nm height and 27.50 nm diameter). The bactericidal action of N-TiO2 thin film A and film B for Pseudomonas aeruginosa strain (AS1.50) and Bacillus subtilis varniger strain (AS1.439) were investigated in this work. More than 95% of photocatalytic bactericidal efficiency for Pseudomonas aeruginosa strain (AS1.50) and 75% for Bacillus subtilis strain (AS1.439) were achieved by using N-TiO2 thin films-B for 70~80 min of irradiation during the photo-bactericidal experimental process. The results indicated that the photo-induced bactericidal efficiency of N-TiO2 thin films probably depended on the characteristics of the films.
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