番木瓜黄色素的初步定性和提取工艺优化

以番木瓜为材料,通过研究不同溶剂对番木瓜色素的提取效果、不同pH值色素颜色的变化以及色素的最大吸光波长,对番木瓜色素进行初步定性;以色素溶液的吸光度为指标,在单因素试验的基础上,利用二次通用旋转试验设计,对番木瓜色素提取的工艺条件进行了优化。结果表明：番木瓜黄色素初步定性为类胡萝卜素,最佳提取条件为：液料比为15∶1、提取温度为50℃、提取时间为60min。     

提高叶绿体色素中类胡萝卜素的提取方法

提高叶绿体色素中类胡萝卜素的提取方法高中《生物》课本中，用新鲜菠菜经层析后叶黄素和胡萝卜素两色素带不够明显，为此，我采用如下方法收到了明显效果。（）研磨绿叶时，除加２～３ｍｌ丙酮外，还加人Ｚｍｌ石油醚，（石油醚、乙醇等醚类能提高类胡萝卜素的提取效率：...     

萱草花瓣中类胡萝卜素分析样品的制备及UPCC-MS检测方法研究

以大苞萱草（Hemerocallis middendorfii Trautv.et Mey.）和‘原谅’萱草（H.‘Pardon Me’）为研究对象,对萱草属植物花瓣中类胡萝卜素的样品制备方法以及UPCC-MS定性和定量检测方法进行了研究。结果表明：（1）萱草花瓣类胡萝卜素样品制备过程中,不同的提取试剂、振荡方法及皂化方法对类胡萝卜素的提取效率均有显著影响,经过对提取结果的方差分析,确定最佳的样品制备方案为：提取试剂B丙酮：正己烷（3：5/V：V）、温控摇床振荡提取,常温皂化16 h;（2） UPCC-MS技术能在10 min内高效分离萱草花瓣中的类胡萝卜素,且使用的有毒化学试剂少,是检测类胡萝卜素的较好选择;（3）大苞萱草和原谅萱草花瓣中共含有20种类胡萝卜素物质,两者颜色不同,类胡萝卜素的组成和含量也存在差异。     

不同北虫草菌株产类胡萝卜素分析

通过对不同来源北虫草菌株子实体中提取的色素进行定性分析并对其含量进行测定,获得类胡萝卜素含量高的北虫草菌株。结果表明,浓硫酸反应中溶液在两相交界处呈现特征性的蓝绿色,色素提取液在400～600 nm范围内有波长分别为415、440和460 nm的3个吸收峰与类胡萝卜素标准的吸收光谱一致,证明子实体中提取的色素为类胡萝卜素;6个菌株子实体类胡萝卜素的含量差异较大,且J菌株的类胡萝卜素的含量最高,达到5.021 mg/g。     

真菌菌丝中类胡萝卜素的提取方法

建立一种从丝状真菌的菌丝体中快速提取类胡萝卜素的方法。发现类胡萝卜素在菌丝体中以色素颗粒形式存在。当饱和NaCl溶液存在于磨碎的菌丝体中,色素颗粒被破坏,类胡萝卜素可以被石油醚萃取。该方法适合根霉属（Rhizopus)、笄霉属（Choanephora)、毛霉属（Mucor)、脉孢霉属（Neurspora)、镰胞霉属（Fusarium)、布拉霉属（Blakeslea）、根霉属（Rhizopus)等丝状真菌菌丝体中类胡萝卜素的提取。     

香蕉皮类胡萝卜素提取工艺条件的研究

为探究香蕉皮类胡萝卜素提取及综合利用的可能性,采用单因素试验与正交试验相结合的方法优化香蕉皮类胡萝卜素的提取工艺条件。结果表明：其最佳提取工艺条件为：以丙酮为提取溶剂、料液比1∶25、提取温度45℃、提取时间75min,在此工艺条件下可获得最佳提取效果,类胡萝卜素提取量平均值为12.541 mg/g。另用超声波辅助提取法,得到香蕉皮中类胡萝卜素提取量平均值为13.740mg/g,在提取时间仅为20min的情况下,比普通浸提法的提取量增加了9.56%,提取效率大大提高。     

产氢红杆菌类胡萝卜素含量和组分分析

类胡萝卜素在调节光合细菌产氢中具有重要作用。采用丙酮－甲醇有机溶剂法和KOH甲醇皂化法对产氢红杆菌（Rhodobacter sp.）R7菌株类胡萝卜素进行了提取纯化,并进一步采用硅胶G薄板层析法对提取的类胡萝卜素进行了分离,并结合光谱法对分离的类胡萝卜素进行了定性和定量分析。结果表明,丙酮－甲醇（7∶2,V/V）提取3次可将色素提取完全;最佳提取时间为2h;超声波处理与否对提取率影响不明显;该工艺提取类胡萝卜素产率为2.81mg/g湿菌体。硅胶G薄板层析表明该菌株类胡萝卜素有4个主要组分：黄色、红色、浅红色和浅黄色,黄色和红色为主要成分,光谱学数据显示黄色组分为球形烯,红色组分为螺菌黄质系类胡萝卜素,表明产氢红杆菌类胡萝卜素代谢途径独特。     

优美红游动菌类胡萝卜素的提取条件研究

研究了优美红游动菌(Rhodoplanes elegans)的生长以及类胡萝卜素的产生,通过比较4种广泛采用的细胞破碎方法,对优美红游动菌(Rhodoplanes elegans)类胡萝卜素的提取条件进行了研究,结果表明:类胡萝卜素的产生与菌种的生长曲线相符合,菌种活化后培养45h,类胡萝卜素的含量趋于稳定;取此时培养液,采用超声波法破碎细胞(破碎功率640W,时间10min),类胡萝卜素提取效果最好,初提液类胡萝卜素的提取率约为7.62mg·(g干菌体)^-1;酸热法对色素的破坏严重。这为进一步开发利用天然色素资源提供了一定的理论依据。     

产氢红杆菌类胡萝卜素含量和组分分析

类胡萝卜素在调节光合细菌产氢中具有重要作用。采用丙酮-甲醇有机溶剂法和KOH甲醇皂化法对产氢红杆菌(Rhodobacter sp.)R7菌株类胡萝卜素进行了提取纯化,并进一步采用硅胶G薄板层析法对提取的类胡萝卜素进行了分离,并结合光谱法对分离的类胡萝卜素进行了定性和定量分析。结果表明,丙酮-甲醇(7∶2,V/V)提取3次可将色素提取完全;最佳提取时间为2h;超声波处理与否对提取率影响不明显;该工艺提取类胡萝卜素产率为2.81mg/g湿菌体。硅胶G薄板层析表明该菌株类胡萝卜素有4个主要组分:黄色、红色、浅红色和浅黄色,黄色和红色为主要成分,光谱学数据显示黄色组分为球形烯,红色组分为螺菌黄质系类胡萝卜素,表明产氢红杆菌类胡萝卜素代谢途径独特。     

红酵母生物合成类胡萝卜素研究进展

类胡萝卜素(carotenoid)是一类呈黄色、橙红色或红色的多烯类化合物,具有预防血管硬化和抑制肿瘤发生,增加宿主免疫力,抗氧化能力和抑制自由基等功能.目前类胡萝卜素已被FAO和WHO等国际组织定为A类营养色素,并在50多个国家获准为营养、色素双重功用的食品添加剂,被广泛应用于保健食品及医药和化妆品工业[1].生产类胡萝卜素可采用提取法、化学合成法和微生物发酵法,其中最有发展前景的是微生物发酵法.目前国内外微生物发酵技术生产天然类胡萝卜素的研究,主要集中在三孢布腊拉霉菌和红酵母等菌种上.利用红酵母生产类胡萝卜素具有营养要求简单,培养周期短,可综合利用等优点,具有很好的应用价值和开发前景.本文主要对红酵母生物合成类胡萝卜素的菌种选育、培养条件及类胡萝卜素的提取检测方法进行了综述.     

Isolation of Toxoplasma gondii from goats from Brazil

Goats are economically important in many countries, and little is known of caprine toxoplasmosis in Brazil. Antibodies to Toxoplasma gondii were assayed in the sera of 143 goats from 3 Brazilian states, using modified agglutination test (MAT titer > or = 1:25); 46 (32.2%) tested positive. Samples of brain, heart, diaphragm, and masseter of seropositive animals were pooled, digested in pepsin, and bioassayed in mice. Viable T. gondii specimens were isolated from tissue homogenates of 12 goats; the isolates were designated TgGtBr1-12. Ten of the 12 isolates killed 100% of infected mice, indicating that goats can harbor mouse-virulent T. gondii and, hence, can serve as a source of infection for humans.     

Guaianolides from two subspecies of Amphoricarpos neumayeri from Montenegro

Quantitative (1)H NMR measurements revealed delta(11(13)) sesquiterpene gamma-lactones as the main constituents ( >or= 1% per weight of dried plant material) in the crude extracts of the aerial parts of Amphoricarpos neumayeri ssp. neumayeri and ssp. murbeckii from mountains Orjen and Visitor (Montenegro), respectively. Preparative silica gel chromatography afforded thirteen guai-11(13)-en-12,6alpha-olides, named amphoricarpolides (1-13), with the same relative (1alphaH,4betaH,5alphaH,7betaH) configuration of the basic skeleton. The common structural feature of lactones 2-13 was 3beta,15-dioxygenation pattern. The only exception was 1 (3-deoxyamphoricarpolide), containing a single oxygen substituent (15-OH). Eight of them exhibited an additional oxygen substituent, 9beta-OH (5 and 6), 2alpha-OH (8-12), or 2alpha-OAc (13). Compound 7 was epoxydated at 10alpha(14)-position, whereas the remaining lactones contained a 10(14) double bond.     

Isolation of protein from humic acid extracted from soil

Summary Chromatography of humic acid in a phenol containing solvent system reveals, in the case of the three types of soil analyzed, the presence of humoprotein containing 11 per cent of nitrogen. Isolation of a humoprotein complex from humic acid, according to the method used by Kirby, followed by paper chromatography allowed the isolation of a protein fraction containing 14.8 per cent nitrogen. This fraction is not dialysable; it has a maximum absorption in ultraviolet light between 260–280 mµ, a small electronegative charge and gives rise to twenty different amino acids. This is the first time that a protein has been separated from humus. Thereby demonstrating that part of the nitrogen contained in humic acid is in the form of protein protected from decomposition.Research supported by the Institut pour l'Encouragement de la Recherche Scientifique dans l'Industrie et l'Agriculture (I.R.S.I.A.).     

Identification of trypanosomes isolated from reduviidae from north Chile

Examination of 54 Triatoma infestans from a village near the European Southern Observatory La Silla in Chile and of 9 Triatoma spinolai from the territory of the observatory showed that 10 T. infestans were infected with trypanosomatids. Mice were infected with in vitro cultures initiated with five different trypanosomatid isolates and treated with the immunosuppressive drug cyclophosphamide to increase the parasitemia of the flagellates. Evidence of the presence of T. cruzi was provided by a comparative biometrical analysis of blood trypomastigotes and the occurrence of intracellular amastigotes. Three methods for further identification were used: examination of kDNA ultrastructure, disc electrophoresis of soluble proteins and the Aaptos papillata II lectin induced agglutination. We obtained the following results for all isolates: (1) presence of a central band of the kDNA; (2) T. cruzi specific double bands of the protein patterns; (3) positive reaction with Aaptos papillata II. No differences between the five isolates from Chile and T. cruzi or T. cruzi-like strains from other countries could be observed. Based on these results an infection of the bugs with T. rangeli and T. conorhini could be excluded.     

Regeneration of peach plants from callus derived from immature embryos

Summary Peach plants were repeatedly regenerated from immature embryos but not from callus derived from mature embryos. A white, nodular, highly regenerative callus was obtained when friable, primary callus from immature embryos was transferred from medium containing 4.5 M 2,4-dichlorophenoxyacetic acid and 0.44 M benzyladenine (BA) to media containing 0.27 M -naphthaleneacetic acid (NAA) and 2.2 M BA. This callus retained its morphogenetic potential for a minimum of three subcultures. Green nodular callus, that lacked regenerative capacity, was produced from primary callus derived from mature embryos. Maximum regeneration of shoots occurred when highly regenerative callus was transferred to a medium in which the NAA concentration was reduced five times and the BA concentration was increased two times. Regenerated shoots were rooted in the dark on a medium containing 28.5 M indoleacetic acid. Cytogenetic analysis of regenerated plants indicated that all plants were diploid, 2n = 2x = 16. Phenotypic evaluation of regenerated plants, grown under field conditions, is now in progress.     

Plant regeneration from protoplasts isolated from cotyledons of Sesbania bispinosa

Protoplasts were isolated from cotyledons of Sesbania bispinosa (Jacq.) W.F. Wight. In a liquid-over-agar culture system with Murashige and Skoog (MS) medium supplemented with 1 mg l^-1 2,4-dichlorophenoxyacetic acid (2,4-d, 2 mg l^-1 benzyladenine (BA), 1 mg l^-1 glutamine and 0.5 and formed callus. The first division occurred after 3–4 days. Callus formed from the protoplasts differentiated shoots by organogenesis on MS medium with 1 mg l^-1 indolebutyric acid (IBA) and 1 mg l^-1 BA. These shoots developed into complete plantlets when excised and cultured on MS medium with 0.5 mg l^-1 IBA.