富铬酵母的理化性质和氨基酸分析

用２００～３００ｎｍ的波长范围对富铬酵母及普通酵母的溶液进行紫外扫描,发现在λ_(２６０ｎｍ)处有一特征紫外吸收峰,富铬酵母细胞的铬含量与其吸收峰的光密度呈线性关系;在不同的温度和ｐＨ值条件下,通过紫外吸收峰的测定,富铬酵母溶液在酸性条件下稳定,在碱性条件下不稳定。溶液的λ_(２６０ｎｍ)紫外吸收峰随着温度的上升而升高。从氨基酸含量分析结果看,富铬酵母的谷氨酸、甘氨酸、组氨酸、丙氨酸和赖氨酸含量高于普通酵母,但其他氨基酸含量比普通酵母低。     

广西桑蚕茧丝质量与性能指标的测定分析

本研究对广西桑蚕茧的茧丝质量与性能指标进行了测定分析.结果表明,广西桑蚕茧外形略小,茧层丝胶含量、茧层易溶丝胶含量、丝胶溶解性以及茧丝纤度等主要指标均与江浙夏秋用桑蚕茧有明显差异.桑蚕茧的茧层丝胶含量、易溶丝胶含量随庄口、季节不同而有显著差异;春季桂南地区的蚕茧茧层丝胶含量高于桂西北地区,秋季刚好相反.茧层易溶丝胶含量在11.6%～14.4%之间,约占丝胶总含量的41%～45%,茧层易溶丝胶含量和解舒率呈显著的正相关关系,即茧层易溶丝胶含量越多,蚕茧解舒越好.庄口和季节是影响桑蚕茧层易溶丝胶含量高低与蚕茧解舒优劣的重要因素.广西桑蚕茧层丝胶对煮茧温度更敏感,茧丝纤度粗细变化开差大.因此,我们认为目前困扰广西桑蚕茧加工技术突破的原因之一是缫丝工艺技术,采用传统缫丝工艺技术难以正常发挥广西桑蚕茧的茧丝优势与特性.     

不同品种菊花和贵州产野菊花中木犀草素的含量比较

目的测定并比较不同品种菊花和贵州产野菊花中木犀草素的含量。方法用高效液相色谱法测定木犀草素的含量。色谱柱为ODS柱（4．6mm×250mm,5μm）,流动相为甲醇-水-冰醋酸（体积比45：55：0．4）,检测波长为254nm,流速1．0mL／min。结果7个菊花样品的木犀草素含量,以贵州野菊花的木犀草素含量最高（3．876mg／g）,杭菊的木犀草素含量最低（0．302mg／g）。结论贵州产野菊花中木犀草素的含量均高于其他品种菊花,具有较高的药用价值。     

A rapid indicator of cultural ecosystem service usage at a fine spatial scale: Content analysis of social media photographs

Cultural ecosystem services (CES) are an important benefit that habitats provide, particularly in the fragments of natural ecosystems that remain in urban areas. To manage CES we need to understand what people use habitats for, and where different activities take place. It is challenging to assess CES provision, as surveys and interviews are time consuming and can be expensive. Social media data, particularly geo-tagged photographs, are spatially explicit and contain visual information that can be used to infer cultural use. Indicators of CES derived from social media make use of existing data so may contribute useful information for rapid, cost-effective assessments of CES. In this study we develop an indicator of CES usage that is derived from photographs from an image-sharing website, at two different scales. First, we compare four small (<150 ha) urban mangrove sites in Singapore, using photograph content to classify sites according to predominant cultural use. Second, the spatial distribution of different CES was modelled within one site using MaxEnt. A resampling simulation was conducted to identify the sensitivity of the photograph classification to the number of photographs classified. Photographs of social recreation, organisms and landscapes occurred most commonly. The proportional occurrence of photograph types differed between sites depending on their characteristics. Within one site, the probability of occurrence of social recreation photographs was highest around built focal points, while photographs of organisms were more likely in the mangrove and terrestrial habitats. Classifying more than 50–70 photographs (which would take approximately 30 minutes) gave only small increases in categorisation accuracy. This tool for CES assessment rapidly provided information that would be useful for managing Singapore's mangroves. The approach could be widely applied to assess CES provision across a range of habitats and settings, helping CES to become more commonly considered in ecosystem service evaluations.     

罗汉果皂甙的含量测定

从罗汉果中提取强甜味剂罗汉果皂甙,并进行了初步分离,以香草醛－高氯酸比色法测定了大中小三种罗汉果中总皂甙的含量,经方差分析,大、中罗汉果总皂甙含量无显著差异,而小果皂甙含量大于中、小中果,提取单位皂甙所需原材料价格以小果为低。若将其作为甜味剂开发使用,以小果最为经济。为开发利用商品性差、价格低的小果,提供了实验研究依据和开发利用途径。     

SIRT1 过表达慢病毒稳转细胞系的构建及其对脂肪合成的影响

目的：通过油红O 及BODIPY染色选取脂肪代谢理想的细胞模型,并运用高内涵仪器检测SIRT1 高表达细胞系中脂肪的 变化。方法：在L-02、HepG2、Huh7 细胞中进行油红O 和BODIPY 染色,观察在不同油酸浓度下脂滴的生成情况;将构建成功的 SIRT1 过表达慢病毒载体GV166-SIRT1 及空载体病毒GV166-Control 感染L-02 细胞,qPCR 及Western-Blot 检测感染细胞中 SIRT1 的表达水平;高内涵系统检测L-02 SIRT1 和L-02 control细胞系产生的脂滴荧光强度,以确定油酸诱导的最佳浓度及最佳 刺激时间。结果：通过油红O 及BODIPY染色发现L-02 细胞更适宜作为脂肪代谢的细胞模型;成功构建SIRT1 过表达慢病毒载 体GV166-SIRT1 及空载体病毒GV166-Control,qPCR 及Western-Blot检测显示转染病毒后SIRT1 在细胞中的表达水平明显升 高;在油酸刺激浓度0.4mM、诱导时间12h 时,L-02 SIRT1细胞中脂滴的荧光强度明显较L-02 control 为低,且这种差异达到最大 化。结论：成功建立SIRT1过表达稳定转染细胞系,并证明高表达SIRT1 能够抑制脂肪合成。     

草鱼肠道纤维素降解细菌的分离与鉴定简

为更好地弄清草鱼(Ctenopharyngodon idella)肠道纤维素降解细菌的种类,采用羧甲基纤维素(CMC)作为唯一碳源的选择性培养基,分别从草鱼肠道内容物和肠道黏膜中分离到了40株产纤维素酶细菌。16S rRNA基因序列的分析结果显示,大多数产纤维素酶细菌为气单胞菌属(Aeromonas)的种类,其次为肠杆菌属(Enterobacter)的细菌以及未经分离纯培养的细菌(Uncultured bacterium)。进一步研究细菌产纤维素酶能力发现,纤维素酶活性显著性高于其他菌株的分别是A.veronii MC2、A.veronii BC6、肠杆菌科(Enterobacteriaceae)中一种未经分离纯培养的细菌BM3(Uncultured bacterium BM3)和A.jandaei HC9。草鱼肠道中简答气单胞菌(A.jandaei)、类志贺邻单胞菌(Plesiomonas shigelloides)、阴沟肠杆菌(E.cloacae)以及产气肠杆菌(E.aerogenes)是被作为产纤维素酶细菌的首次报道。     

United Arab Emirates: Phylogenetic relationships and ancestral populations

In the current report, 109 unrelated individuals from the United Arab Emirates (UAE) were typed across 15 autosomal short tandem repeat (STR) loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D149S433, vWA, TPOX, D18S51, D5S818 and FGA) routinely employed in population genetics analyses and compared across a set of ethnically and geographically targeted reference collections. UAE, located at the southeastern most portion of the Arabian Peninsula, in the tri-continental crossroads connecting Africa, Europe and Asia, has been influenced by a number of human dispersal waves from a plethora of sources including the Paleolithic “Out of Africa” migrations, the exodus of Neolithic pastoral agriculturalists from the Fertile Crescent and Northern Africa, as well as more recent migrations from Asia and the Middle East. We found that despite the high levels of consanguinity that characterize UAE, this population is genetically highly heterogeneous. When compared to various world-wide biogeographical regions, the Arabian Peninsula exhibits the highest intra-population variance. Admixture analyses indicate that UAE and Bahrain uniquely in Arabia share 23.7% and 22.9%, respectively, of their DNA with Southwest Asian populations. Similar and complex Structure profiles are seen among Arabian Peninsula populations underscoring the high genetic diversity of the region. Although UAE shares a number of genetic characteristics in common with the rest of the populations in the Arabian Peninsula, it is unique in terms of its relative high Asian genetic component, likely the result of geographical proximity to Southwest Asia, west-bound waves of migration and socio-political ties with territories to the east.     

双歧杆菌双元蛋白酸奶中特定菌含量及酸度的检测

目的 :检测双歧杆菌双元蛋白酸奶中发酵前后以及在贮藏期间的双歧杆菌和乳酸菌活菌数及酸度的变化。方法 :应用改良MRS琼脂平板法检测含菌量 ,应用吉尔涅尔度表示酸度 (°T)。结果 :双歧杆菌双元蛋白酸奶中双歧杆菌含量为 3 1× 10 7CFU/ml,乳酸菌含量为 4 1× 10 8CFU/ml;°T为 6 5± 5。随着贮藏进程的延长 ,特定菌的含量随贮藏期进程而下降 ,第 4～ 5天下降明显 ;°T随贮藏期延长而逐渐上升 ,保质期内°T为 75～ 110之间。结论 :双歧双元蛋白酸奶符合酸奶国家GB2 74 6～ 1999标准。