Research progress and application of microbial origin naringinase

柚皮苷是影响柚子汁品味的最主要因素,柚苷酶具有将柚皮苷分解为普鲁宁、鼠李糖、葡萄糖和柚皮素等物质的功能,并且这些物质已广泛用于制药和饮料行业。本文介绍了近年来国内外微生物来源的柚苷酶的研究、酶学特性、酶活测定、结构与功能等,表明细菌来源的柚苷酶最适温度为37~70℃,最始PH值为4.5~8.0;真菌来源的柚苷酶最适温度为30~75℃,最始PH值为4.0~11.0。介绍了柚苷酶及其相关产物在食品、饮料和制药工业中的应用进展,发现柚苷酶不仅具有脱苦的作用,还对人类的身体健康具有重要作用。展望了今后的研究方向,应该从柚苷酶高产菌株的选育、发酵产酶的工艺优化和酶的应用等方面开展工作,大幅度提高柚苷酶的产酶水平。Naringin is the principal factor which bitters the taste of grapefruit juice.Naringin could be hydrolyzed by naringinase into prunin,rhamnose,glucose,and naringenin,which have wide applications in the pharmaceutical and beverage industry.This paper provides an overview of the studies on microbial origin naringinase,purification,characterization and determination of enzyme activity as well as protein structure and function.The optimum temperature of naringinase from bacteria is from 37 ℃ to 70 ℃ while the optimal pH is in the range of 4.5 to 8.0;the optimum temperature of naringinase from fungal is from 30 ℃ to 75 ℃ while the optimal pH is in the range of 4.0 to 11.0.The applications of naringinase and its various products in food,beverage,and pharmaceutical are also presented,showing that naringinase could not only debitter the fruit juice but also play an important role in human health.In addition,the development trends and potential applications of naringinase are also prospected.The research emphasis should be placed on screening ideal microbe strains and fermentation process optimization to enhance naringinase

PREPARATION AND CHARACTERIZATION of FeMo CofACTORS CONTAINING SINGLE AND DOUBLE Mo FROM NITROGENASE

固氮酶单、双钼铁钼辅基的制备与n-甲基甲酰胺碱度有关.质子激发X射线发射光谱和电感耦合等离子体发射光谱分析技术测定单、双钼铁钼辅基的钼铁流元素组成比值均为1∶6∶6.在紫外可见光谱区内，单、双钼铁钼辅基均无特征吸收峰，不含高柠檬酸盐。Preparation of FeMo cofactors containing single and double Mo was related with basicity of N-methylFormamide.The mininal elemental composition of FeMo cofactor containing single and double Mo was Found to be Mo: 6Fe: 6S by using inductively coupled plasma and proton induced X-ray emission analytical technique.F6Mo cofsctors containing single and double Mo showed Featureless absorbence peak in the ultraviolet and visible spectral range and did not contain homocitrate.国家自然科学基金;国家教委回国留学人员基

细菌铁蛋白氧化还原特性及电极活性的研究

棕色固氮菌细菌铁蛋白能直接快速地从金属铂电极上得到电子或提供电子给铂电极。经－６００ｍＶ（相对于ＮＨＥ）还原电位处理后，还原态细菌铁蛋白在可见光谱区中（３８０－５８０ｎｍ）所呈现的整体吸收光谱强度明显高于氧化态细菌铁蛋白的吸收光谱强度。经氯化钴处理后的细菌铁蛋白表现出较弱的电极活性及释放铁的速率明显下降。此外，细菌铁蛋白在体外模拟棕色固氮菌整体细胞内的微量氧环境体系中仍有氢还原现象，因而推测细菌铁蛋白在该菌体内也能进行吸氢反应。细菌铁蛋白是一种类似有吸氢氢酶功能的蛋白

猪脾铁蛋白电子隧道特性及释放铁途径的研究

维生素Ｃ和连二亚硫酸钠混合后只能加速猪脾铁蛋白释放铁的速率，并不能使铁蛋白释放铁的动力学途径由复杂转化为简单．而单独维生素Ｃ却能利用蛋白壳上的电子隧道传递电子，迫使铁蛋白以二分之一的反应级数方式释放整体铁核的铁并起着抗磷酸盐阻遏释放铁速率的作用，简化释放铁的途径．对维生素Ｃ参与铁蛋白释放铁的机理进行了讨论

CT三维成像诊断寰枢关节不全脱位的临床价值

目的　评价CT三维成像对寰枢关节不全脱位的显示及诊断价值 ,探讨最佳三维成像方法。　方法　回顾性分析 4 1例寰枢关节不全脱位的CT影像学表现 ,比较横断面图像、多层面重建 (multiplanarreformatting ,MPR)法、表面遮盖 (surfaceshadedisplay ,SSD)法、最大强度投影(maximumintensityprojection ,MIP)法及容积重建 (volumerendering,VR)法三维图像显示的病变情况。　结果　寰枢关节不全脱位 4 1例 ,其中旋转型脱位 31例 ,前脱位 5例 ,后脱位 5例。影像学表现为上、下关节面错位 4 1例 ,其中错位 2～ 5mm 2 9例、5～ 9mm 12例 ;齿突侧距不对称 15例 ;寰齿间隙增宽合并骨折 8例。SSD法三维影像直观显示移位的寰枢关节上、下关节面 ,齿突侧距不对称及寰齿间隙增宽 ;横断面图像和MPR、MIP及VR法三维图像显示移位的上、下关节面差、不直观。　结论　运用CT三维成像能准确显示及诊断寰枢关节不全脱位 ,并以SSD法三维成像最佳

马脾铁蛋白释放铁的反应级数和速率相数的转换

采用差示法研究铁蛋白释放铁的动力学规律和反应级数的转换。结果表明：马脾铁蛋白释放铁的速率及相数与还原剂Na2S2O4。浓度及铁还原速率无关，与该蛋白蛋白壳的调节速率有关。在pH50～6．0范围内，马脾铁蛋白以三相不同速率方式释放占原铁核总铁量80％的铁。但在pH9．0介质中，OH-不仅能参与铁蛋白铁核组成，减缓释放铁的速率，而且使原混合级反应转换为一级反应，从而使铁蛋白释放铁的动力学过程由复杂转化为简单

棕色固氮菌细菌铁蛋白释放铁的动力学方程和性质

棕色固氮菌细菌铁蛋白铁核中的磷铁组成存在非均匀性。细菌铁蛋白释放铁的动力学特性表现出复杂性。通过动力学曲线分析，提出蛋白壳自身调节能力起着限制释放铁速率关键步骤的观点，建立分析铁蛋白释放铁的动力学特性方程并用它较合理地阐明铁蛋白释放铁的动力学规律及储存铁的途径。用分光光度法和动力学方程研究细菌铁蛋白释放铁的全过程，其结果表明该蛋白以一级反应方式释放铁核表层的铁和以零级反应方式释放铁核内层的铁。外加磷酸盐能强烈地抑制释放铁的速率，引起释放铁的反应级数的转化，迫使铁蛋白以一级反应的方式释放铁核中的大多数铁。国家教委回国留学人员基金;福建省自然科学基

Study on the Nutrient Content of Bamboo Leaves and Soil in Coastal Region of Fujian

第一作者简介：陈松河，男， 1968年出生，福建长泰人，研究员，硕士生导师，硕士，主要从事园林植物（竹类）分类、栽培与抗逆性研究。通信地址： 361003厦门市思明区虎园路 25号， Tel：0592-2039619，E-mail：[email protected]。[中文文摘]为了研究福建滨海地区竹类叶片与土壤养分状况,对福建滨海3地厦门园博苑百竹园、莆田赤港华侨农场竹园和莆田湄洲岛竹类植物叶片和土壤养分进行实地调查取样分析。结果表明:3地17种竹类成熟叶片和衰老叶片氮(N)、磷(P)含量存在显著差异,且存在明显的地域性差异;竹类生长土壤氮(N)含量均值大小依次为厦门园博苑0.3697mg/g、莆田赤港0.2820mg/g、莆田湄洲岛0.1921mg/g;磷(P)含量均值大小依次为莆田湄洲岛0.3926mg/g、厦门园博苑0.3134mg/g、莆田赤港0.2152mg/g;莆田赤港和莆田湄洲岛10种竹类成熟叶片叶绿素a含量(Ca)和叶绿素b含量(Cb)均值比达到2.17,Ca和Cb间经11种单因子模型拟合,最优的拟合方程为:YA=0.9699+3.7374B-0.7166B2+0.0439B(3A代表Ca,B代表Cb),相关系数的平方达0.934,呈极显著相关关系;竹类植物盐害等级为0级的有5种,盐害等级为1级的有10种,盐害等级为2级的有2种,盐害等级为3级以上的未见。[英文文摘]In order to study nutrient status in bamboo leaves and soil,3 coastal region in Fujian, Xiamen Garden & Flower Expo (XMYB), Farm for Returned Overseas Chinese in Putian (PTCG) and Meizhou Island of Putian (PTMZ) were studied in this paper by field investigation and sampling analysis. The results were shown as follows: the content N and content P in mature and senescent of 17 species leaves in 3 coastal region were significant difference, also significant difference in region. The average value content N of bamboo soil inXMYB, PTCG, PTMZ were 0.3697, 0.2820, 0.1921 mg/g in turn. The average value content P of bamboo soil inPTMZ, XMYB, PTCG were 0.3926, 0.3134, 0.2152 mg/g in turn. The proportion of 10 mature bamboo speciesaverage value between content Ca and content Cb was 2.17, through 11 models of single factor analysis, the relation between the bamboo’s chlorophyll a content and chlorophyll b content accorded with model cubic: YA= 0.9699 + 3.7374B-0.7166B2 + 0.0439B3 (A stands for content Ca, B stands for content Cb), the square of itscorrelation coefficient was 0.934, it was very significant. Bamboo salt damage 0 degree had 5 species, 1 degreehad 10 species, 2 degree had 2 species, no species in 3-5 degree.厦门市科学技术局科研项目“竹类植物耐盐机理与筛选应用研究”(3502Z20102003);厦门市市政园林局科研项目“竹类植物在观赏园艺上的应用研究”(YK-2000-02

Cellulase Production by Solid-state Fermentation and Saccharification Using the Fibre of the Energy Plant Erianthus arundinaceum

作者简介:张树河(1975 年—),男， 助理研究员。研究方向： 能源植物的选育及转化制生物燃料。 通讯作者： 龙敏南， E-mail:[email protected][中文文摘]以能源植物斑茅(Erianthus arundinaceus)为材料,对其纤维成分、产酶条件和糖化条件进行了分析。结果表明:斑茅含有纤维素43.77%、半纤维素28.57%、木质素11.01%;对斑茅进行预处理后,纤维中纤维素的含量提高至72.54%,半纤维素含量降低至13.02%,木质素的含量降低至3.34%。利用预处理的斑茅纤维进行固态发酵产酶,其最佳的产酶条件为:茅麸比1∶3,固液比1∶2,氮源(脲)0.75%,初始pH 5.0,32℃发酵培养72 h;相对于利用未经预处理的斑茅纤维为原料,其FPA酶活提高210.9%,达到20.74 U/g,CMC酶活提高239.1%,达到218.26 U/g。以纤维素酶对斑茅纤维进行糖化,糖化率达到40.60%。[英文文摘]Using energy plant Erianthus arundinaceus as the material,we analysed the fiber composition,enzyme production conditions and saccharification.The results showed that Erianthus arundinaceus consisted of 43.77% cellulose,28.57% hemicellulose and 11.01% lignin.After pretreatment,the cellulose content increased to 72.54%,while the hemicellulose and lignin content decreased to 13.02% and 3.34%,respectively.The optimal condition for solid-state fermentation to produce cellulase was: ratio of pretreated cellulose fibre to wheat bran 1 ∶ 3, ratio of solid to liquid 1:2, nitrogen source(urea)0.75%, initial pH 5.0, temperature 32 ℃ and fermentation time 72 h. When using the pretreated fibre as the carbon source, the FPA activity and CMC activity increased 210.9% and 239.1%, respectively. The pretreated fibre was used for saccharification under the optimal condition with a yield of 40.60%.国际科技合作重点项目(No.2009DFA60930);; 国家自然科学基金(No.31170067)资

Damage to mangroves from extreme cold in early 2008 in southern China

通讯作者Author for correspondence (E-mail: [email protected])2008年初,我国南方19个省经历了50年一遇的持续低温雨雪冰冻天气。极端气候对华南沿海各省的红树林区造成不同程度的危害。2008年3月,在我国南方各省红树林区的10个代表性地点,对这次寒害造成的红树植物伤害程度进行了系统的调查。结果表明:冬季低温对红树林的影响极为显著,特别是在低纬度的海南、广西和广东湛江,由于极端低温正值夜间退潮,对红树林的影响更为显著;在纬度较高的福建,本地红树种类秋茄(Kandelia obovata)、桐花树(Aegiceras corniculatum)和白骨壤(Avicennia marina)及引种的木榄(Bruguiera gymnorrhiza)等,由于长期适应于冬季较低的气温或在种植前经过抗寒锻炼,具有较强的抗寒能力。各地主要红树植物中,广布种秋茄、桐花树和白骨壤最为耐寒,其耐寒性均大于红树科的木榄、海莲(Bruguiera sexangula)和红海榄(Rhizophora stylosa)。海桑(Sonneratia caseolaris)对温度的敏感性最强,抗寒能力最低,因此,即使在其原产地海南也受到较为严重的寒害,在纬度更高的引种地出现大面积受害甚至全部死亡,而从孟加拉国引种的无瓣海桑(Sonneratia apetala)却显示出一定的抗寒能力。同一地点的红树植物幼苗的抗寒能力低于大树。此次寒害也造成了苗圃场的种苗大量死亡,成熟的植株提前落花落果,这势必会影响后继一两年内红树林的自然更新和人工造林。因此,在未来红树林造林或人工引种中,一定要考虑到红树植物的抗寒能力。国家自然科学基金(30671646和30700092);厦门大学“闽江学者”启动基