995 resultados para Rose, Jalen


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The ever-increasing population of the world and the growing need for animal protein has doubled the modern man’s demand for food. Additionally, the improvement in the general public health, and the worsening of environmental/ecological pollution have prompted today’s world to look for ways to procure healthy food. And one such attempt is the use of natural preservatives to decrease the bacterial load in foodstuffs, in other words, to increase their durability. This study evaluates the effects of different concentrations of Zataria multiflora Bioss (EO 0, 0.005, 0.015, 0.045, 0.135, 0.405%) and Nisin (0, 0.25, 0.5, 0.75 μg/ml) and storage time (9 days) on the growth of Lactococcus garvieae Ir-170A(856bp) alone, and their combination in a food model system (fillets of the rainbow trout (Oncorhynchus mykiss). Additionally, the growth of a sample of this bacteria in laboratory conditions was studied. The results of this study showed that different concentrations of Nisin had a significant impact (p<0.05) on Lactococcus garvieae. With the value of t in 0.75 μg/ml, the effectiveness rose to 65.77%; the biggest effect on Lactococcus garvieae. And the effect at 4 0C exceeded 80C. The study has also demonstrated that all concentrations of Zataria multiflora Bioss were effective against Lactococcus garvieae. However, with the value of t at 0.405%, the effectiveness was 71.91%. This value had the biggest effect on Lactococcus garvieae. At 4 0C, the effect surpassed the one at 80C. The synergistic effects of the EO and Nisin showed that with the value of t at 0.405% EO and 0.75 μg/ml Nisin was 14.62% had the greatest effect on Lactococcus garvieae. In this study, multi-factorial effects for different concentrations of Zataria multiflora Bioss (EO 0, 0.005, 0.015, 0.0025%), three different concentrations of 122 Nisin (0, 0.25,0.75 μg/ml) and two different levels of PH (5.5 , 7) at two incubation temperatures (15,37) on logp% of Lactococcus garvieae during 43 days in BHI broth were evaluated. Most of the effects on Lactococcus garvieae occurred in PH 5.5 and at a temperature of 150C.

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In five groups of seasonally provisioned Tibetan macaques (Macaca thibetana) at Mt. Emei, males were sampled for wounds as an indicator of their competition for females during about 80 days in the 1987 mating season. Quantitative data on intergroup transfer were collected in a period between June 1986 and December 1987. The young adult (YA) males, the most active age-class in mating activity and intergroup transfer, received most of the wounds. Wounds tended to appear more in the front of body for YA and subadults (SA) than they did for middle-old aged (MO) males. This implies that some of the MO males were more active and aggressive in the fights. During the 1.5 year period, 5/6 of the YA and 5/17 of the MO males made intergroup shifts. Although YA males faced a high risk of receiving wounds at transfer, they usually rose in rank. On the other hand, the MO males transferred more smoothly but dropped in rank. The peripheral SA males, which rarely emigrated in the population, were an active component in determining the wounding rate, and the rate and direction of male migration. Three SA immigrants died of severe attacks made by resident males in 1988 and 1991. Adult sex ratios and their variations were considerably reduced with male nonrandom shifts and better conservation of the population.

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We present a multiplexing scheme for the measurement of large numbers of mesoscopic devices in cryogenic systems. The multiplexer is used to contact an array of 256 split gates on a GaAs/AlGaAs heterostructure, in which each split gate can be measured individually. The low-temperature conductance of split-gate devices is governed by quantum mechanics, leading to the appearance of conductance plateaux at intervals of 2e^2/h. A fabrication-limited yield of 94% is achieved for the array, and a "quantum yield" is also defined, to account for disorder affecting the quantum behaviour of the devices. The quantum yield rose from 55% to 86% after illuminating the sample, explained by the corresponding increase in carrier density and mobility of the two-dimensional electron gas. The multiplexer is a scalable architecture, and can be extended to other forms of mesoscopic devices. It overcomes previous limits on the number of devices that can be fabricated on a single chip due to the number of electrical contacts available, without the need to alter existing experimental set ups.

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Changes in growth, photosynthetic pigments, and photosystem II (PS II) photochemical efficiency as well as production of siderophores of Microcystis aeruginosa and Microcystis wesenbergii were determined in this experiment. Results showed growths of M. aeruginosa and M. wesenbergii, measured by means of optical density at 665 nm, were severely inhibited under an iron-limited condition, whereas they thrived under an iron-replete condition. The contents of chlorophyll-a, carotenoid, phycocyanin, and allophycocyanin under an iron-limited condition were lower than those under an iron-replete condition, and they all reached maximal contents on day 4 under the iron-limited condition. PS II photochemical efficiencies (maximal PS II quantum yield), saturating light levels (I-k ) and maximal electron transport rates (ETRmax) of M. aeruginosa and M. wesenbergii declined sharply under the iron-limited condition. The PS II photochemical efficiency and ETRmax of M. aeruginosa rose , whereas in the strain of M. wesenbergii, they declined gradually under the iron-replete condition. In addition, I-k of M. aeruginosa and M. wesenbergii under the iron-replete condition did not change obviously. Siderophore production of M. aeruginosa was higher than that of M. wesenbergii under the iron-limited condition. It was concluded that M. aeruginosa requires higher iron concentration for physiological and biochemical processes compared with M. wesenbergii, but its tolerance against too high a concentration of iron is weaker than M. wesenbergii.

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Two types of microfabrics relating to pollutant adsorption were studied in the scanning electronic microscope (SEM) in a polluted, eutrophic lake, the Yangtze delta region. Agglutinational texture or the aggregates of small particles are composed of clay minerals and fine organic fragments among the silty grains and the coatings with a thickness about 1 mu m were on the surfaces of the silty grains in the sediments. The chemical constituents of the aggregates and the coatings are K, Na, Ca, Mg, Si, Al, O, Fe, Ti, C, N and P determined in X-ray energy spectrometry connected with the SEM. In some cases, Pb was detected in the aggregates in the top sediment. It is suggested that nutrients and metals are adsorbed to the aggregates, which were formed by electrostatic attraction of physicochemical floes. The coatings on the surface of quartz grains were formed by the interaction of dissociated Al, Si, Fe, etc from silicates with dissolved N, P and C nutrients in interstitial water, which was aroused by human pollution to the lake in recent two decades.

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A sediment core was collected from the centre of Wanghu Lake, in the Middle Reaches of the Yangtze River. The recent part of the core was dated using a combination of Pb-210 and spheroidal carbonaceous particle (SCP) techniques. Extrapolating this chronology dated the laminated section of the core, between 723 and 881 mm, to the first half of the 18th century and this section was selected for detailed study. The thicknesses of the laminae were measured using reflecting and polarizing microscopes whilst geochemistry was determined by an electron probe. The thickness of the dark layers was found to be positively correlated with titanium concentrations, and negatively correlated with aluminium and potassium concentrations. The thickness of the light layers was found to be negatively correlated with the concentrations of titanium. It is concluded that the dark layers were deposited from the Fushui River, a tributary of the Yangtze River, under periods of normal flow whilst the light Layers were mainly deposited from the Yangtze River itself during flood periods. Documentary evidence for floods occurring in the take catchment corresponded with thick laminations of high titanium concentration. Further, two of the three thickest, light laminations with low titanium concentrations were found to be synchronous with recorded flood dates of the main Yangtze River in its Middle Reaches, but one was synchronous with a local drought. These data suggest that the Lake sediment provides an archive of the relative water levels of the Yangtze and Wanghu including floods of both the main Yangtze River and the local hydrological regime. (c) 2006 Elsevier B.V. All rights reserved.

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Body length, instar duration, fecundity, and survival rate of Moina irrasa from a subtropical Chinese lake were studied at three food concentrations (4, 8, and 40 mg/L, wet weight) and six temperatures (10, 15, 20, 25, 30, and 35degreesC) in the laboratory. Body length tended to decrease with increase of temperature, while the trend was reversed as food concentration rose. M. irrasa had three juvenile instars, except there were four at 10degreesC, and the number of adult instars showed great variation (3-15). Water temperature and food concentration both affected the duration time of adult instars. The largest broods were from the third to sixth adult instars, depending on food and temperature, and the mean highest number of offspring per brood was 56 at 25degreesC. A significant relationship between body length and brood size appeared at high (40 mg/L) and medium (8 mg/L) food concentrations, while there was no significant relationship at low food concentration except at 25 degreesC. The intrinsic rate of population increase ranged between 0.104 and 1.825 ind./day.

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分析了电子轰击电荷耦合器件(EBCCD)微光成像系统的噪声源,建立了系统的信噪比模型,指出了在微光成像系统本身的增益和量子效率等性能确定的条件下,成像系统输出图像信噪比不仅仅与输入面照度有关,还与输入图像的空间频率有关,并通过实验得到了证明,指出了经典的图像探测方程(Rose方程)的不完善之处.

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本文以沈阳市于洪区玫瑰种植示范区内多季花冷香玫瑰和单季花平阴玫瑰为研究对象,通过野外采样并测定了两者在花芽分化期矿质元素(P、K、Ca、Mg、Fe、Zn、B、Mn、Cu)和内源激素(IAA、GA、ZR、ABA)的含量,并对其含量及比值变化进行分析,初步确定了玫瑰花芽分化与元素、激素之间的相互关系。研究结果将为玫瑰花期的化学调控、提高产花量和正确制定栽培技术措施提供理论依据,也为玫瑰进一步开发利用打下基础。主要结论:1.在冷香玫瑰和平阴玫瑰的整个花芽分化期,P、K、Cu、Zn大体上均呈下降趋势,表明它们可能参与玫瑰成花;ca、Mg在冷香玫瑰和平阴玫瑰的花蕾形成期含量都下降,可能意味着ca、Mg参与两者的花蕾形成;Fe与玫瑰花芽分化关系不大;高含量的B和Mn有利于两者花蕾形成。2.在冷香玫瑰和平阴玫瑰花蕾形成期,IAA和GA出现低水平,ZR和ABA出现高水平,激素比值(ABA/GA,ABA/IAA,ZR/GA,ZR/IAA)出现高水平,表明ABA和ZR促进两者开花;而IAA和GA抑制两者开花;高比例的(ABA/GA,ABA/IAA,ZR/GA,ZR/IAA)有利于两者开花。

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在自由分子流和连续介质的高超声速驻点热流经典解的基础上,通过无量纲分析给出了适用于整个流动领域的高超声速驻点热流公式即 ,其中 , 为来流Knudsen数,轴对称情况 ,二维情况 。上述关系与Rose和Stark、Koppenwallner、Metcalf等轴对称、圆柱和球柱的高超声速稀薄气体实验数据相符。对比DSMC方法计算得到的高超声速非平衡稀薄气体圆柱和圆球绕流驻点热流(樊菁和沈青 1994, Dogra等 1991),证明上述关系在热力学和化学非平衡效应显著情况下也是适用的。

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繁殖更新是植物生活史的重要阶段,在退化生态系统中,植物繁殖更新能力往往较差,是植被恢复的限制环节,因而也成为恢复研究重点和核心。本研究选择岷江干旱河谷广泛分布的三种蔷薇:多苞蔷薇(R. multibracteata)、黄蔷薇(R. hugonis)和川滇蔷薇(R. soulieana)为研究对象,通过野外调查,在查明其生长、繁殖更新状况的基础上,采用控制和模拟实验,对种子和幼苗阶段进行了深入研究,综合分析更新潜力,并提出相对应的促进更新和植被恢复措施。主要结论如下: 1)三种蔷薇在岷江干旱河谷广泛分布,生长和繁殖状况良好,结实量大。各生长指标:株高、基径和冠幅,繁殖指标:结实数量、重量和单果重量都具有显著的空间差异性。基径对多苞蔷薇结实量影响最大;而冠幅对黄蔷薇结实量影响最大。海拔和纬度是对蔷薇生长和繁殖影响最大的环境因素,随着海拔和纬度的升高,植株生长更高大,结实量增加;坡度和坡向对其生长和繁殖也有一定影响,随着坡度 和坡向增加,蔷薇生长和结实受到抑制。 2)三种蔷薇在岷江干旱河谷更新现状不佳, 但更新潜力大。活力种子比率低,动物取食以及两年生幼苗的大量死亡是蔷薇更新的主要限制因素。多苞蔷薇和黄蔷薇的结实率低,川滇蔷薇较高。三种蔷薇种子产量大,但种子质量较差,更新具有充足的种源。三种蔷薇都能形成持久种子库,种子库中种子总量大,但有效种子少,黄蔷薇被动物啃食的比例很高,多苞蔷薇和川滇蔷薇也有一部分种子受到动物破坏。三种蔷薇幼苗库组成特征表现为,当年生幼苗所占比例很高,年龄较大幼苗所占比例小。 3)三种蔷薇都具有不同程度休眠,未经处理种子的发芽率极低。黄蔷薇休眠程度最深,为深度生理休眠;多苞蔷薇为中度生理休眠;川滇蔷薇为非深度生理休眠。三种蔷薇种子在形态上发育成熟,种皮具有透水性。蔷薇果果肉和瘦果中含有抑制物质,其浸泡液抑制了油菜种子萌发,果肉抑制作用更强,果肉和瘦果浸泡液的抑制程度分别为:川滇蔷薇>黄蔷薇>多苞蔷薇。切割和硫酸腐蚀提高了川滇蔷薇种子的发芽能力,而对多苞蔷薇和黄蔷薇没有影响。完全去除瘦果果皮和种皮提高了多苞蔷薇种子发芽率,但对黄蔷薇没有影响。赤霉素和烟水对蔷薇种子萌发没有促进作用。三种蔷薇打破休眠所需低温层积时间分别为:黄蔷薇>多苞蔷薇>川滇蔷薇。对于多苞蔷薇和川滇蔷薇,层积前对种子进行硫酸腐蚀或暖温层积能缩短低温层积时间,提高发芽率。对于多苞蔷薇,变温层积中暖温层积和低温层积具有一定的负补性,即延长暖温层积可以缩短种子萌发对低温层积的需要。 4)多苞蔷薇种子形态特征和种子休眠与萌发在不同海拔梯度间存在较大差异。种子采集时间、采集季节和干藏影响多苞蔷薇和川滇蔷薇的种子休眠。多苞蔷薇果实大小、种子大小和千粒重、种皮厚度随海拔升高而增加,而种子饱满率和活力随海拔升高而降低,种子休眠程度也随海拔升高而增加。种皮厚度与种子大小、千粒重成正相关关系,硫酸腐蚀后的种子经过不同时间的低温层积后,种子发芽率与种皮厚度、种子大小、千粒重、海拔成正相关关系。2006 年采集川滇蔷薇和多苞蔷薇种子休眠程度较2005 年低。种子休眠随种子年龄增加而减弱。高温和干旱能减轻多苞蔷薇和川滇蔷薇种子休眠。 5)三种蔷薇的生长和生物量积累在干旱胁迫条件下受到抑制,而生物量分配、叶片形态特征和水分利用特征等都发生了变化。三种蔷薇的根、茎、叶各器官生物量以及总生物量等在干旱胁迫下明显减小,叶片脱落数量增加。在干旱胁迫条件下,较多的生物量分配到地下部分,从而这使R/S 明显增加。比叶面积(SLA)和冠层面积比(LAR)对干旱胁迫的反应不敏感,仅有部分物种在干旱胁迫条件下发生了变化,并且其变化特点在不同年龄幼苗之间有一定差异。干旱胁迫对WUE 的影响在不同物种间存在差异。多苞蔷薇和黄蔷薇的WUE 随着干旱胁迫的增加而增大, 而川滇蔷薇的WUE 则随干旱胁迫增加而减小。在干旱胁迫条件下,多苞蔷薇和黄蔷薇叶片脱落量和生物量减小幅度较川滇蔷薇大,表明其抗旱能力较强。在干旱胁迫条件,三种蔷薇两年生幼苗的生物量减小幅度较当年生幼苗小,表明两年生幼苗的抗旱能力更强。 6)两种植被恢复措施中,幼苗移栽比播种具有更好的植被恢复效果。播种后,蔷薇种子的发芽率较高,但出苗率都很低,即使出苗,幼苗也几乎在一月内全部死亡。 三种微生境条件下(灌木、半灌木和裸地),种子出苗和幼苗成活没有差异。移栽幼苗总体死亡率都比较低,小于20%。特别是两年生幼苗死亡率更低,小于2%。移栽后的幼苗生长状况良好,在整个生长季中,各生长指标不断增加。生境对幼苗的存活率没有显著影响,但对于幼苗的生长和生物量积累有一定影响,裸地更有利于幼苗生长和生物量积累。与当年生幼苗相比,两年生幼苗具有更高的成活率。总之,三种蔷薇在干旱河谷分布广泛、生长繁殖状况良好,结实量大,具有丰富种源,繁殖更新潜力大,但繁殖更新状况不佳;种子散布后动物对种子的取食、种子的深度休眠过程、种子出苗以及当年生幼苗的存活和定居是更新的主要限制环节。水分是影响结实、种子休眠解除和萌发,幼苗存活和定居的最主要的限制因素。在植被恢复中,应在种子成熟季节大量采集种子,在室内打破休眠后进行人工播种,培育两年生幼苗,通过幼苗移栽方式进行植被恢复。川滇蔷薇应栽种在相对湿润的过渡区,而多苞蔷薇和黄蔷薇可以应用于核心区植被恢复。 Regeneration is an important phase in plant life cycle. It has been a key component of ecological restoration in degradation ecosystem in which plants commonly has poor regeneration. In this paper, we investigated the natural growth, propagation and regeneration status of native three rose species, Rosa multibracteata, R. hugonis and R. soulieana, and analysis the limitation in seed germination and seedling establishment stages. Advice on facilitating the use of these plants in restoration based on the results has been proposed. The results were as follows: 1) Three rose plants widely distributed in the dry valley of the Minjiang River, and made a good performance in growth and propagation. There were significant spatial differences in each growth parameter, such as ramet height, basal diameter, crown diameter and propagation parameters including hip number of a clump, hip mass of a clump and a hip mass. Basa diameter was the most important growth parameter influencing fruit number for R. multibracteata and crown diameter was for R. hugoni. Altitude and latitude had the greatest effect on the growth and propagation of rose plants among environmental conditions. Each parameter of growth and propagation increased with the increase of altitude and latitude. In addition, the increase of slope and aspect limited the growth and propagation. 2) Three rose plants had poor natural regeneration, but great regeneration potential. Low seed viability, predation and higher mortality of current year old seedlings were the limitation in regeneration. R. multibracteata and R. hugonis had higher fruiting rates than R. souliean. All three plants produced a great number of seeds, while their viability was poor. Three rose plants had persistent seed banks, with high total seed number but very low viable seed density. Predation was most severe in R. hugonis, and it also existed to some degree in R. multibracteata and R. soulieana. The seedling age-structure was characteristic of current-year seedlings predominating and few older seedlings were observed. 3) Three rose seeds were dormant and untreated seeds germinated with very low germination percentages. The rose seeds had morphological mature embryos, and achenes were permeable. Some inhabit substances existed in hips and achenes for the extracts of hips and achenes inhibited germination of Brassica campestris. The inhibition effect of the extracts of three rose hip and achenes was R. soulieana>R. hugonis>R. multibracteata. Mechanical and H2SO4 scarification increased R. soulieana germination but had no effect on germination of R. hugonis and R. multibracteata seeds. Full removal of pericarp and testa improved the germination of R. multibracteata but did not affect R. hugonis germination. GA3 and smoke water had no positive effect on rose seed germination. The periods of cold stratification required to released seed dormancy was R. hugonis > R. soulieana >R. multibracteata. H2SO4 scarification and warm stratification shortened cold stratification to release dormancy for R. soulieana and R. multibracteata. Warm stratification had complementary effect for cold stratification, i.e. the longer warm stratification seeds received, the shorter cold stratification were required to obtain the same germination percentage. Three rose seeds had different kinds of dormancy; R. hugonis has deep physiological dormancy, R. multibracteata with intermediate physiological dormancy and R. souliean non-deep physiological dormancy. 4)The seeds traits and dormancy of R. multibracteata showed significant difference across altitudes. Year and season of seed collection had significant effect on seed dormancy for both R. souliean and R. multibracteata. Hip size, seed size, seed weight, seed coat thickness and seed dormancy level increased with the increase of the altitude. There were positive relations between seed coat thickness with seed size and seed weight. Germination percentage of seeds treated with H2SO4 scarification following different periods of cold stratification showed positive relation with seed coat thickness, seed size, seed weight and altitude. Seeds of R. souliean and R. multibracteata collected in 2006 had low dormancy level than those collected in 2005. Seed dormancy decreased with increasing seeds age. High temperature and drought were associated with low dormancy level. 5) Seedling growth, the total dry mass and their components of seedlings were reduced, while leaf senescence accelerated under drought stress. More biomass allocation to root system resulted in higher R/S ratio under drought. Water-use efficiency (WUE) of R. multibracteata and R. hugonis increased, while it declined for R. soulieana under drought stress. R. soulieana seedlings had poor drought-resistance capacity it had more senescent leaves, and its reduction of biomass was stronger than two other rose plants under drought. The reduction degree of one year old seedlings under drought stress was slighter than that of current year seedlings. Therefore, one year old seedling was more drought-resistent compared to current year seedlings. 6)Planting seedlings may have better effect in comparison with direct seeding. Most seeds germinated after seeding, but seedling emergence was very low. More than 80 % seedlings from direct seeding died within a months after emergence. Seedling emergence and survival rate did not show difference among microhabitats. Mortality rates of seedlings artificially planted in microhabitats were general lower than 20 %, and the mortality rate of one year old seedlings was lower than 2 %. Each grow parameter including plant height, leaf number and branch number continually increased after planting. Microhabitat type had effect on the growth parameter and biomass production, but it did not influence the seedling survival. Bare land tended to facilitate seedling growth. One year old seedlings had higher survival rate than current year seedlings. In conculsion, the three rose had wide distribution in the dry valley of the Minjiang River. They produced many seeds and had tolerance to drought stress to some degree. But they had poor regeneration in habitats may be caused by predation, seed dormancy,and high mortality in current year seedlings. We recommend that rose plants should be utilized in restoration by planting two-year old seedlings in spring. A large quantity of seeds should be collected artificially in autumn, release seed dormancy in room, and then cultivate two-year old seedlings by seeding in particular container. R. soulieana seedling probably be planted in transition area, and R. multibracteata and R. hugonis can be used in core area of the dry valley of the Minjiang River.

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对15株白腐真菌进行了以玉米秸秆为基质的初步筛选,从中获得一株选择性系数较高的菌株Y10,并对其降解玉米秸秆的情况进行了研究。结果表明,在30天的培养过程中菌株Y10对玉米秸秆降解的选择性系数都大于1,第15天选择性系数最高为3.88。对未经降解和降解过的玉米秸秆分别作了紫外光谱和红外光谱分析,结果表明,经该菌降解后玉米秸秆的化学成分发生了很大变化,且木质素的降解程度要大于纤维素的降解程度。对菌株Y10进行了ITS-5.8S rDNA序列鉴定,初步判定其为Cerrena sp.。 为了考查不同的外源添加物对菌株Y10降解玉米秸秆的影响,在以玉米秸秆为基质的固态发酵培养基中分别添加了7种金属离子、8种碳源、6种氮源。结果显示,这7种金属离子均能促进木质素的降解,并且一定浓度的某些离子明显抑制纤维素的降解;其中添加0.036%的MnSO4·H2O和0.36%的MgSO4·7H2O对纤维素降解的抑制作用比较强,降解率分别为0.96%和1.31%,木质素的选择性系数分别达到了34.40和20.17。8种碳源中除麦芽糖外都能促进木质素的降解,除微晶纤维素外都明显促进纤维素的降解。6种氮源中酒石酸铵、硫酸铵、草酸铵和氯化铵的添加都会使该菌生长变慢,而且氮源浓度越高菌丝生长越慢。外加碳源和金属离子对半纤维素降解和选择性系数的影响不大。 同时对菌株Y10在液态培养下产木质素降解酶的条件和培养基做了优化。结果表明,在初始产酶培养基中,菌株Y10的漆酶酶活在第10d达到最高,锰过氧化物酶酶活在第11d达到最高,基本上检测不到木质素过氧化物酶。菌株Y10产漆酶的最适温度为32℃,最适PH为6.0;产锰过氧化物酶的最适温度为32℃,最适PH为6.5。菌株Y10产漆酶的最佳碳源为甘露糖,最佳氮源为酒石酸铵,最适诱导剂VA浓度为3 mmol/L,最适表面活性剂TW-80浓度为1%。 利用响应面法对其产漆酶的培养基进行优化,优化后的培养基配方为葡萄糖10.00 g/L,酒石酸铵0.50 g/L,大量元素296.50 ml/L,微量元素100.00 ml/L,NTA 1.40 g/L,VA 5.00 mmol/L,吐温-80加入量为0.10%。进行了菌株Y10产漆酶的验证实验,实测酶活为5282.56 U/L,与预测酶活5162.73 U/L接近。在优化后培养基中,菌株Y10在第14 d达到生长的最高峰,第20 d时,漆酶酶活最高,为11325.00 U/L;第16 d时,锰过氧化物酶酶活最高,为30.77 U/L。 对菌株Y10的漆酶酶学性质做了初步的研究,结果显示,酶反应的最适温度为40℃-65℃,最适PH为3.0。在40℃,PH=3.0时,漆酶催化ABTS反应的米氏方程为 。 Fifteen white-rot fungi based on corn stalk were screened. One white-rot fungus Y10 with high selectivity value was obtained. The degradation of corn stalk was initially studied. The results indicated that the selectivity value was above 1 during the 30 day-cultivation and the highest was 3.88 after 15 days. The composition of untreated and treated stalk was analyzed through ultraviolet spectroscopy and infrared spectroscopy. It was found that the composition of treated stalk was greatly altered and the degree of the degradation of lignin is greater than the cellulose. Y10 was identified as Cerrena sp. by ITS -5.8S rDNA sequence analysis. The influence of metal ions, carbon sources and nitrogen sources on corn stalk degradation by white-rot fungus was studied. While all seven metal ions could promote lignin degradation, the cellulose degradation was best inhibited at certain ion concentrations. Notably, when 0.036% MnSO4·H2O and 0.36% MgSO4·7H2O were added into the medium, the cellulose degradation was restrained to the extents that the coefficients of lignin selectivity rose to 34.40 and 20.17 respectively. It was also found that all carbon sources except maltose can promote lignin degradation. The addition of carbon sources other than microcrystalline cellulose significantly promoted cellulose degradation. The addition of the nitrogen sources, ammonium tartrate, ammonium sulfate, oxalate, ammonium chloride, resulted in remarkable inhibition to mycelium growth; the larger the concentrations of nitrogen sources are, the slower the mycelium grew. The addition of carbon sources and metal ions had less impact on the degradation of hemicellulose and selectivity value. Meanwhile, we optimized the conditions and culture medium of the lignin-degrading enzyme production of strain Y10. The results showed that in the initial culture medium, the Lac activity was highest at the 10th day, the MnP activity was highest at the 11th day and the LiP could not be detected. The optimum condition of Lac was at temperature 32 and PH =6.0 and the optimum condition of MnP was at temperature 32 and PH =6.5. The optimum carbon source for Lac was seminose, the optimum nitrogen source was ammonium tartrate, the optimum content of VA was 3 mmol/L, the optimum content of TW-80 was 1%. PB and RSM were used to optimize the culture medium of laccase by white-rot fungus Y10. The optimum culture medium was consist of glucose 10.00 g/L, ammonium tartrate 0.50 g/L, macro elements 296.50 ml/L, trace elements 100.00 ml/L, NTA 1.40 g/L, VA 5.00 mmol/L, TW-80 0.10%. Under the optimal conditions, the activity of laccase was 5282.56 U/L and the experimental value agreed with the predicted value 5162.73 U/L. The biomass was highest at the 14th day, the Lac activity was highest at the 20th day, the MnP activity was highest at the 16th day. The results of the studies on the characteristics of Lac showed that the optimum temperature for Lac activity is 40℃-65℃ ; the optimum PH for Lac activity is 3.0 and under 40℃,PH=3.0, the Michaelis-menten equation of Lac catalized ABTS oxidation was .