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1.
Callus induced from leaf explants of Pueraria lobata seedlings were suspended in Gamborg B5 medium supplemented with 1 mg l(-1) 2,4-dichlorophenoxyacetic acid, 1 mg l(-1) naphthalene acetic acid, 0.5 mg l(-1) kinetin and 30 g l(-1) sucrose. The effects of coconut milk and casein hydrolysate (CH) on cell growth and yields of puerarin and isoflavones in cells suspension were studied. The contents of total isoflavones and puerarin in suspension cultures were determined by spectrophotometry and HPLC. Coconut milk (10%, filter sterilized) decreased the growth of cell cultures and the accumulation of total isoflavones, while 0.2% CH promoted the growth of cell cultures and the accumulation and release of puerarin and total isoflavones. The total yield of puerarin and isoflavones were 34% and 40.8% higher than in the control, respectively. The optimum medium for cell cultures of leaves of P. lobata seedlings was B5 liquid medium supplemented with 2% sucrose, 1.0 mg l(-1) 2,4-D, 1.0 mg l(-1) NAA, 0.5 mg l(-1) kinetin and 20 mg l(-1) CH. The procedure use is a potentially useful for the production of isoflavones.  相似文献   

2.
野葛、山葛和三裂叶葛的离体叶片与发展根农杆菌R1601直接感染诱导出毛状根并能够合成葛根素,毛状根离体培养后均出现两种形态:一种是有较高的葛根素含量的典型毛状根,另一种是葛根素含量低但生长速度较快的愈伤组织化毛状根,两类毛状根均有rol/B基因存在,表明rolB基因对所有毛状根的诱导和生长是必需的,aux1存在于所有愈伤组织化毛状根,而在典型毛状根中的检出率为20%-50%,表明aux1基因有诱导毛状根产生愈作组织的作用,含有ags基因的毛状根葛根素含量低于不含ags基因的毛状葛根素含量,表明ags基因不利于次生代谢合成,表3参12  相似文献   

3.
A study on major inorganic ion composition of atmospheric aerosols   总被引:1,自引:0,他引:1  
Atmospheric aerosol samples were collected from Akola and Buldana region covering around 40 sqkm area during October-November 2002 and were analyzed for ten major inorganic ions namely F-, Cl-, NO3-, SO4(2-), PO4(2-), Na+, K+, Ca2+, Mg2+ and NH4+ using ion chromatographic technique. The average mass of aerosols was found to be 225.81 microg/m3 with standard deviation of 31.29 and average total water soluble load of total cations and anions was found to be 4.32 microg/m3. The concentration of ions in samples showed a general pattern as SO4(2-) > NO3- > Cl- > PO4(2-) > F- for anions and Na+ > Ca2+ > NH4+ > Mg2+ > K+ for cations. The overall composition of the aerosols was taken into account to identify the sources. The trend showed higher concentration of sodium followed by calcium, sulfate, nitrate, phosphate and ammoinum and found to be influenced by terrestrial sources. The presence of SO4(2-) and NO3- in aerosols may be due to re-suspension of soil particles. Ca2+, Mg2+ and Cl- are to be derived from soil materials. The presence of NH4+ may be attributed to the reaction of NH3 vapors with acidic gases may react or condense on an acidic particle surface of anthropogenic origin. The atmospheric aerosol is slightly acidic due to neutralization of basicity by SO2 and NO(x).  相似文献   

4.
影响雨生红球藻797株生长和虾青素积累的某些因素   总被引:7,自引:0,他引:7  
研究了雨生红球藻 (Haematococcuspluvialis) 797株的N源需求和营养盐吸收 ,并利用高光强和乙酸钠处理该藻 ,研究虾青素累积情况以及超氧化物歧化酶 (SOD)活性、营养盐、细胞状态的变化 .NH+ 4 N培养的生长速率明显高于NO-3 N培养 ,平均生长速率分别为 0 .2 79d-1和 0 .190d-1.NH+ 4 N培养所消耗的N、P营养盐比NO-3 N培养的消耗少 .两种N源下强光照处理 1d和 7d均导致雨生红球藻细胞数减少而静细胞比例增加 .在虾青素合成阶段 ,藻液N含量急剧下降而P含量基本保持稳定 ,说明虾青素合成对N的需要量大而对P的需要小 .在NO-3 N培养下 ,乙酸钠的加入则对虾青素的生产无显著影响 .在NH+ 4 N培养下SOD活性下降而虾青素含量升高 ;在NO-3 N培养下SOD活性与虾青素含量同时升高 .图 2表 4参 15  相似文献   

5.
北京冬季一次重污染过程PM2.5中水溶性无机盐的变化特征   总被引:14,自引:0,他引:14  
为了解北京冬季重污染过程大气颗粒物化学特性,利用高时间分辨率实时在线细粒子快速捕集及化学成分分析系统(RCFP-IC)对2011年2月18—24日发生的一次重污染过程PM2.5中水溶性无机离子浓度变化进行了在线观测.结合颗粒物质量浓度、气态污染物浓度及气象资料,对此次污染过程中污染物的化学成分变化特征进行了详细分析.结果表明,此次北京冬季重污染4 d中颗粒物污染严重;总水溶性无机离子平均质量浓度151.31μg·m-3,占PM2.5相对比例54%,其中NO3-、SO24-和NH4+质量浓度占总水溶性无机离子质量浓度91%,二次离子污染非常严重;硝酸根氧化率(NOR)和硫酸根氧化率(SOR)结果显示NO3-与SO24-主要通过非均相反应生成,水溶性无机盐存在形态以NH4HSO4和(NH4)2SO4为主;重污染期K+和Cl-质量浓度显著升高,Mg2+和Ca2+质量浓度下降;阳、阴离子电荷比(C/A)重污染平均值为0.8,细粒子偏酸性.  相似文献   

6.
春节燃放爆竹对大气气溶胶水溶性无机离子的影响   总被引:4,自引:0,他引:4  
2007年冬季在兰州市区进行了连续30天的大气气溶胶观测取样,重点对春节燃放与非燃放烟花爆竹期间,大气气溶胶水溶性阴离子(F-、Cl-、NO2-、Br-、NO3-、PO34-、SO23-、SO24-)和水溶性阳离子(Li+、Na+、NH4+、K+、Mg2+、Ca2+)的污染状况做了研究。结果显示:春节燃放烟花爆竹会使大气污染加重,大气气溶胶质量浓度日均值比非燃放期上升了22.4%,其中使气溶胶粗颗粒(TSP)上升5.5%,气溶胶细颗粒(PM10)上升55.1%,呈细粒污染加重现象。部分水溶性离子浓度在燃放期间明显升高。上升幅度最大的是K+,其次为SO32-、NO3-、NH4+、SO42-、Cl-、F-、Mg2+、Li+、NO2-等离子。除夕夜采集的大气气溶胶样品,粗细颗粒中K+浓度分别为27.413μg/m3和26.180μg/m3,比非燃放期平均含量高出10.70倍和11.52倍。  相似文献   

7.
施用尿素和硫酸铵对红壤硝化和酸化作用的影响   总被引:6,自引:0,他引:6  
通过室内恒温培养试验,研究施用CO(NH2)2和(NH4)2SO4对初始pH值分别为5.14、4.77和4.34的红壤酸化速率和硝化速率的影响。结果表明,施用CO(NH2)2显著增加了3种红壤的硝化速率,从而显著加速土壤酸化。培养结束时,3种红壤pH值较培养过程中最高值分别下降2.14、1.23和0.56。施用(NH4)2SO4抑制了初始pH<5.0的2种红壤的硝化作用,从而显著降低这2种红壤的硝化速率和酸化速率,但显著增加了初始pH>5.0红壤的硝化速率,对其酸化速率则未见显著影响。3种红壤的酸化速率与硝化速率间存在显著线性相关关系。硝化作用是导致农田红壤pH值下降的主要原因之一,但不同氮肥对红壤硝化速率和酸化速率的影响不同。  相似文献   

8.
This paper reports the successful culture of Pueraria lobata (Willd.) suspension cells in a bioreactor. In vitro culture of this Chinese herb has potential as an alternative production method for industrial applications. Calli of P. lobata obtained from leaf explants were cultured in a 5.0 L bioreactor for two weeks. During this period, the pH of the medium declined from 5.8 to 4.5. By the end of the run about 70% of the sugars and reducing sugars and about 50% of nitrate was consumed. Almost 70% of inorganic phosphate and about 80% of the iron was exhausted. The bioreactor results indicated an isoflavone yield of 328.9 microg/ml, with an increase of about 1.77 fold. The yield of puerarin increased about 2.42 fold and reached 73.4 microg/ml in the bioreactor culture.  相似文献   

9.
大气气溶胶无机组成的FTIR测定及与离子色谱分析的比较   总被引:4,自引:0,他引:4  
梁咏梅  王美蓉 《环境化学》1997,16(5):456-462
利用傅立叶变换红外光谱仪,固体制样方式,对北京市中关村地区的气溶胶样品中的无机组成进行了分析,并对气溶胶样品中的SO4^2-,NH4^+和NO3^-进行了定量测定,为检验FTIR测定法的可靠性,将FTIR法与离子色谱的测定结果进行了对照分析,结果表明,SO4^2-和NH4^的FTIR测定结果与离子色谱有较好的相关性。  相似文献   

10.
V2O5/AC催化剂对氨还原NO的研究   总被引:16,自引:0,他引:16  
考察了V2O5/AC催化剂对NH3选择催化还原NO的影响,结果表明,以浓硝酸预氧化处理的活性焦为载体对催化剂活性有很大提高,这是由于浓硝酸预氧化后,活性焦表面产生了较多的含氧官能团可能吸附更多的NH3,并且提高了活性组分V2O5的含量,反应气氛中加入SO2后,二都活性都增加,但差异消失,这是由于SO2存在时,反应生成的SO4^2-离子的酸性强于浓硝酸预氧化产生的含氧官能团的酸性,催化剂在使用前经过煅烧和氧化对催化剂活性有很大改善。SO2存在时,V2O5含量为1wt%的催化剂活性提高。  相似文献   

11.
华重楼内生菌Iun35的分离及其抗菌蛋白的性质   总被引:2,自引:0,他引:2  
从华重楼(Paris polyphylla Smith var.chinensis)块茎中分离纯化得到一株具有较强抑菌活性的内生细菌Iun35,经形态特征、生理生化特性及16S rDNA鉴定为枯草芽孢杆菌(Bacillus subtilis).将分离得到的Iun35菌株发酵培养,培养液上清经硫酸铵分级沉淀、Sephadex G-75凝胶柱层析和DEAE-32纤维素柱层析分离纯化出一种抗菌蛋白UD35.用该蛋白对多种植物病原菌进行拮抗测定,结果显示,UD35对玉米纹枯病菌(Rhizoctonia solani Kuha)、小麦赤霉病菌[Gibberelle zeae(Schw.)]等多种菌有强烈抑制作用.测定其相对分子质量约为55 000,氨基酸分析结果表明其由17种氨基酸组成.图3表4参16  相似文献   

12.
To understand the short-term effects of forest gap by human harvesting on soil available nutrient in Pinus massoniana plantations, the variations of soil ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3-N) concentrations in the gap center and gap edge during growing season were observed in seven gaps of different size (Gl: 100 m2; G2:225 m2; G3:400 m2; G4:625 m2; G5:900 m2; G6:1225 m2; G7:1600 m2) and pure understory of a 39-year-old masson pine plantation in a hilly area of the upper reaches of Yangtze River. The results showed that in the early stage of gap formation, the gap size had significant effect on NH4+-N, the season changes on NP3--N, and the interaction effect of gap size and seasonal variation on NH4+-N and NO3--N. The difference of NH4+-N and NO3--N between the gap center and gap edge was not significant. (I) The NH4+-N content was 4.30-11.99 mg kg-1, and NO3--N content was 2.57-10.81 mg kg-1. There was no obvious difference in NH4+-N and N03--N among gaps of different size in early or late growing seasons, when both increased first and decreased afterwards in the middle of growing season. The gaps of 100∼400 m2 area had a higher content of available nitrogen. (2) The seasonal dynamic differed between NH4+-N and NO3--N, with the former lower in middle growing season whereas the latter higher in the middle growing season but lower in the end of growing season. The soil NH4+-N was higher than NO3- -N in the early and late periods, but lower in the middle period. (3) The soil NH4+-N and NO3--N in parts of gaps were lower than understory in the early and late growing season. (4) Correlation analyses showed that NH4+-N had significant positive correlation with microbial biomass nitrogen (MBN), and NO3--N with soil temperature, MBN and organic matter. But the impact of soil water content on available nitrogen was not significant. These results suggested that soil temperature and microbial activity variation caused by gap harvesting are the main factors affecting soil available nitrogen content of Pinus massoniana plantations.  相似文献   

13.
常州市酸雨化学特征及其与大气污染物的关系   总被引:1,自引:0,他引:1  
收集了常州市2008年全年的56次降水,并分析了它们的9种主要离子的浓度及pH值。全年降水的pH雨量加权平均值为4.76。降水酸度和大气中气态污染物及可吸入颗粒物呈正相关性。气态污染物及可吸入颗粒物的冲刷净化直接影响降水的pH值及其化学成分。SO42-、NO3-、Ca2+和NH4+是影响降水pH值的主要离子。常州市2008年的降水主要酸性离子SO42-和NO3-浓度明显高于我国降水背景点纳木错,但低于其他部分城市,表明常州市的大气环境受到了明显的人为污染,但污染程度相对较轻。常州市的环境空气质量在近20年内得到了明显的改善。  相似文献   

14.
对上海市1992-2007年湿沉降监测结果进行研究,16年来,上海市湿沉降主要呈现以下特征:pH总体呈现下降趋势,酸雨频率呈现上升趋势;2002年起升幅很大;硫酸根离子和钙离子浓度总体呈下降趋势,2003年后,各离子浓度都有一定程度下降;钙离子在总阳离子中的比例总体上明显下降,铵离子与总阳离子的百分比总体上呈上升趋势;硫酸根离子在总阴离子中的比例有所下降,硝酸根离子与总阴离子的百分比则一直呈上升趋势;硫酸根与硝酸根年均值的比值总体上呈明显的下降趋势,表明硫酸型在逐渐减弱;钙离子与铵离子的比值总体上也呈明显的下降趋势。  相似文献   

15.
In order to evaluate their responses to drought, we determined the photosynthetic activity water potential, stomatal conductance, transpiration, water use efficiency photosynthetic photon flux density and leaf temperature of Paulownia imperialis, P. fortunei and P. elongata in three different soil moisture conditions in the field. Our results showed that P. imperialis had greater photosynthesis (8.86 micromol CO2 m(-2) s(-1)) and instantaneous water use efficiency (0.79 micromol CO2 mmol H2O(-1)) than either P. elongata (8.20 micromol CO2 m(-2) s(-1) and 0.71 micromol CO2 mmol H2O(-1)) or P. fortunei (3.26 micromol CO2 m(-2) s(-1) and 0.07 micromol CO2 mmol H2O(-1)). The rapid growth of Paulownia did not appear to be correlated with photosynthetic rates. Paulownia fortunei showed more transpiration (48.78 mmol H2O m(-2) s(-1)) and stomatal conductance (840 mmol m(-2) s(-1)) than P. imperialis (20 mmol H2O m(-2) s(-1) and 540 mmol m(-2) s(-1)) and P. elongata (20 mmol H2O m(-2) s(-1) and 410 mmol m(-2) s(-1)), which allowed these two Paulownia species to increase their tolerance to low soil moisture, and maintain higher water use efficiency under these conditions. According to our physiological gas exchange field tests, Paulownia imperialis does appear to be capable of successful growth in semiarid zones.  相似文献   

16.
灰泥土中不同氮肥品种反硝化损失与N2O排放量的差异   总被引:4,自引:0,他引:4  
在实验室培养条件下,采用土壤培养-乙炔抑制法测定尿素、碳酸氢铵、硫酸铵和氯化铵4种氮肥品种在灰泥土中反硝化损失和N2O排放量的差异。结果表明,氮肥品种间的N2O排放量和反硝化损失量存在极显著差异。尿素、碳铵和氯化铵的N2O排放量极显著高于硫铵,占施肥量的3.88%-4.14%;尿素和碳铵的反硝化损失量分别为施肥量的5.8%和3.7%,极显著高于硫铵和氯化铵;但氯化铵的反硝化损失量显著低于CK。  相似文献   

17.
初步实验证实螯台球菌(Chelatococcus daeguensis)TAD1在高温下具有异养硝化-反硝化的能力,为验证其可应用性,采用曝气生物滤池工艺,研究了TAD1在温度为50℃的异养硝化-反硝化性能.结果表明,TAD1在曝气生物滤池中可同时进行好氧反硝化和异养硝化.当分别以硝氮、氨氮及硝氮和氨氮为氮源时,12 h的氮去除率均达到100%,氮的去除能力分别为12.67 mg.L-.1h-1、3.62 mg.L-.1h-1及16.53 mg.L-.1h-1.虽然在脱氮过程中,亚硝盐在6 h迅速积累到76 mg.L-1(硝氮为氮源)和52.6 mg.L-1(硝氮和氨氮为氮源),但在随后的几个小时内又快速降低至0(检测限之外).因而,TAD1具有应用于高温生物脱氮工艺的能力和优势.  相似文献   

18.
不同磷水平下植物体内镉的积累、化学形态及生理特性   总被引:8,自引:0,他引:8  
在控制条件下,将玉米、小麦植株在含有不同浓度磷(c(P)0,0.12,0.6,3.0mmol/L)和镉(c(Cd)0,4.0μmol/L)的营养液中培养21d,研究植株体内各种镉的形态、生理特性和酶活性的变化,选择三种主要镉的形态,即氯化钠可提取态(镉与蛋白质或多肽结合态),醋酸可提取态(镉与磷酸盐的结合态)和去离子水可提取态(水溶性、有机酸盐镉的形态)作为优势态镉加以分析和研究。结果表明,提高介  相似文献   

19.
Diurnal trends in net photosynthesis rate (P(N)), stomatal conductance (g(s)), water use efficiency (WUE) and biomass were compared in six-month-old seedlings of Albizia lebbeck and Cassia siamea, under different levels of drought stress. The potted plants were subjected to four varying drought treatment by withholding watering for 7 (D1), 14(D2) and 25 (D3) days. The fourth group (C) was watered daily and treated as unstressed (control). Species differed significantly (p < 0.001) in their physiological performance under varying stress conditions. Higher P(N) of 11.6 +/- 0.05 in control followed by 4.35 +/- 0.4 in D1 and 2.83 +/- 0.18 micromol m(-2) s(-1) in D2 was observed in A. lebbeck. A significant (p < 0.001) reduction in P(N) was observed in C. siamea (C 7.65 +/- 0.5 micromol m(-2) s(-1), D1, 2.56 +/- 0.33 micromol m(-2) s(-1) and D2, 1.4 +/- 0.01 micromol m(-2) s(-1)) at 9 hr. A positive correlation was seen between P(N) and g(s) (A. lebbeck, r2 = 0.84; C. siamea, r2 = 0.82). Higher WUE was observed in C. siamea (D2, 7.1 +/- 0.18 micromol m(-2) s(-1); D3, 8.39 +/- 0.11 micromol m(-2) s(-1)) than A. lebbeck, (control, 7.58 +/- 0.3 micromol m(-2) s(-1) and D3, 8.12 +/- 0.15 micromol m(-2) s(-1)). The chlorophyll and relative water content (RWC) was more in A. lebbeck than C. siamea. Maximum biomass was produced by A. lebbeckthan C. siamea. From the study, one could conclude that A. lebbeckis better than C. siamea in adopting suitable resource management strategy and be best suited for the plantation programs in the semi-arid dry lands.  相似文献   

20.
Benthic community respiration and the cycling of N and P were seasonally investigated in the unprotected, sandy sediments (Z5m) of the nearshore zone of the Georgia Bight, USA in 1981 and 1982. Nutrient exchange across the sediment-water interface was calculated from a diffusive model, measured by in-situ enclosure experiments and estimated from whole core incubations. Seasonally changing pore water profiles indicated that the sediments were not in steady-state with respect to N and P and showed the characteristics of enhanced interstitial water movement by benthic animals. Over an annual period the total flux of nitrogen measured in situ averaged 1812 mol m-2 d-1 from the sediments. NH 4 + flux accounted for the vast majority of the total directly measured N flux (77%), followed by nitrate + nitrite (14%), and dissolved organic nitrogen (9%). Phosphorus flux averaged 537 mol m-2 d-1. A large ratio of in-situ fluxes to calculated diffusive fluxes (5.2:1) indicated flux enhancement due to benthic animal activity. ammonium fluxes measured in situ did not agree well with the rate of NH 4 + produced in incubated whole cores (11.7 mmol m-2 d-1). Relative rates of C, N and P release throughout the year fluctuated considerably. Generally, nutrient fluxes were not simply related to respiration or temperature. As respiration was highly correlated with temperature, however, this suggested that respiration-regeneration was temporarily decoupled from exchange across the sediment-water interface. The annual C-N-P flux stoichiometry was 130:3.1:1. Using the rate at which NH 4 + was produced in incubated cores the stoichiometry was 120:21:1. The anomalously low N flux measured in situ was attributed to a combination of denitrification and wave-and current-induced sediment nutrient flushing. The potential for sediment flushing is high as experiments showed that sediments were fluidized or resuspended down to 25 cm during large storms. Benthic nutrient flux contributed 40% to the annual P but only 11% to the annual N requirements of the pelagic primary producers.This is Contribution No. 558 from the University of Georgia Marine Institute. This work was supported by the Georgia Sea Grant College Program maintained by the National Oceanic and Atmospheric Administration, US Department of Commerce, under Grant No. NA80AA-D-00091  相似文献   

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