基于Cite Space对螺旋藻藻蓝蛋白的研究进展与热点分析

螺旋藻(Spirulina)藻蓝蛋白具有独特的理化特性及生理功能,是药物、食品和化妆品的天然原料,具有较大的开发潜力。为探讨螺旋藻藻蓝蛋白的研究现状与发展前景,对中国知网和Web of Science数据库中1990—2023年发表的文献进行检索并筛选,使用Cite Space软件对文章发文量、研究团队及研究热点进行图谱分析。综合分析可知,国内年发文量偏少,呈平稳趋势;国外年发文量持续上升,尤其近几年发文量迅速增长,且发文量超过了100篇;国外研究热点集中于藻蓝蛋白在食品、医药行业的应用方面,而国内研究热点集中在提取纯化、稳定性、功能活性的研究与应用,下一步应结合研究现状开发适合规模化生产的提取纯化工艺,进一步加强藻蓝蛋白研究的广度与深度;国内外研究群体主要是高校的相关生物技术学院或研究机构等,总体来讲,学者间存在较为密切的合作,但研究机构间尚未形成紧密的合作关系,在地域上比较分散,各大高校和研究机构应突破地区或机构间的各种限制,促进该研究领域的深度融合和快速发展,深入挖掘藻蓝蛋白在各个领域的潜在应用。

胃蛋白酶酶法改性藻蓝蛋白及其稳定性研究

目的探究胃蛋白酶酶法改性藻蓝蛋白在不同温度和pH条件下的呈色和结构稳定性。方法通过比较藻蓝蛋白在胃蛋白酶改性前后的分子量变化和色度色差,确定最佳的改性条件;利用紫外-可见吸收光谱和圆二色谱分析改性对藻蓝蛋白结构的影响;并通过液相色谱-质谱技术分析改性藻蓝蛋白的肽段序列;最终以色度和色差、色素保留率、紫外-可见吸收光谱和圆二色谱等指标,评价改性藻蓝蛋白在不同温度和pH下的呈色和结构稳定性。结果藻蓝蛋白的最佳改性条件为酶解pH 2.0、灭酶方式煮沸6 min、酶解时间2 h。此条件下改性藻蓝蛋白与未改性藻蓝蛋白相比,紫外-可见吸收光谱显示藻蓝蛋白分子结构发生变化,圆二色谱结果说明酸性和酶解条件会导致藻蓝蛋白从典型的α-螺旋结构向无序结构转变。通过液相色谱-质谱联用技术,本研究鉴定到7条含有藻蓝胆素的肽段序列,这些肽段与藻蓝胆素的稳定结合对维持改性藻蓝蛋白的呈色稳定性起关键作用。稳定性评价结果表明,改性藻蓝蛋白在高温和酸性环境显示出优异的呈色和结构稳定性。70℃以下的温度范围内,色素保留率大于(91.25±0.08)%,关键色度b^(*)和二级结构占比无显著变化;在pH 2.0附近时改性藻蓝蛋白呈色和结构最稳定。结论本研究所得改性藻蓝蛋白较未改性藻蓝蛋白在高温和酸性环境的呈色和结构稳定性显著提升,为藻蓝蛋白在食品加工过程中应用于不同食品基质、应对不同加工处理条件提供理论基础和技术支持。

藻蓝蛋白面霜的制备与性能研究

研究以藻蓝蛋白作为原料制备的面霜,探究其抗氧化、抗紫外线活性和吸湿保湿性能.对A(PEG 100硬脂酸甘油硬脂酸酯、鲸蜡硬脂醇、甘油硬脂酸酯、石蜡油、十四酸异丙酯)、B(甘油、丁二醇、黄原胶、EDTA二钠、藻蓝蛋白)两相原料进行处理,混合均匀后制得面霜;以抗坏血酸作为对照组,测定藻蓝蛋白的DPPH清除率、还原性、总抗氧化活性,以及面霜的抗紫外线性能和吸湿保湿能力.结果显示,当藻蓝蛋白浓度为1.6 mg/mL时,其对DPPH的清除率可达89.20%,还原和总抗氧化能力均较强,吸湿率和保湿率的大小,以及抗紫外线的能力均优于市售欧珀莱面霜样品.以藻蓝蛋白为原料制备面霜既可以发挥其功效性作用,又可以实现对天然生物成分的有效利用,能够为化妆品的发展开拓新方向.

Structure and Function of ε-Subunit of ATP Synthase in Higher Plant Chloroplast

The ε-subunit is the smallest subunit of chloroplast ATP synthase, and is known to inhibit ATPase activity in isolated CF1-ATPase. As a result ε is sometimes called an inhibitory subunit. In addition, and perhaps more importantly, the ε -subunit is essential for the coupling of proton translocation to ATP synthesis (as proton gate). The relation between the structure and function of ε -subunit of ATP synthase in higher plant chloroplast has been studied by molecular biological methods such as site-directed mu-tagenesis and truncations for C- or N-terminus of ε -subunit. The results showed that: (1) Thr42 of ε-subunit is important for its structure and function; (2) compared with the ε-subunit in E.coli, the ε-subunit of chloroplast ATP synthase is more sensitive to C- or N-terminus truncations.

基于620 nm藻蓝蛋白特征吸收峰提取蓝藻水华光谱指数的方法研究

湖库蓝藻水华为全球性水生态环境问题之一,藻蓝蛋白是蓝藻水华的特征标志物,在620 nm处具有明显吸收的特性,为此利用620 nm波段开展湖库蓝藻水华提取方法研究具有重大意义。本研究基于Sentinel-3数据,利用余弦定理计算光谱曲线上第7波段(中心波长为620 nm)与相邻波段反射率的夹角,构建出新型蓝藻水华光谱指数-PCAI(Phycocyanin Angle Index),并应用于太湖和大通湖蓝藻水华的提取,同时与NDVI、PCI、MCI等指数法的蓝藻水华提取结果、藻密度实测浓度、藻蓝蛋白反演浓度进行比对,研究PCAI指数法提取蓝藻水华的可行性和适用性。结果表明:①本研究构建的光谱指数PCAI,能够准确表征藻蓝蛋白的生物量和水华程度,以角度的形式表示水华程度,较其他指数更加形象、直观。②从太湖和大通湖水华分布、强度和面积来看,PCAI指数法与PCI指数法的蓝藻水华提取结果基本相当,与NDVI指数法仅部分甚至极少部分结果相当或接近,与MCI指数法较为接近,但其非水华区域MCI值相对较高。③采用PCAI指数法提取蓝藻水华,克服了NDVI指数法对较重水华过饱和、对轻度或轻微水华识别极不灵敏的问题,避免了MCI指数法易受富营养化水体中叶绿素a影响的问题,较PCI指数法更易于判定蓝藻水华程度。④PCAI与藻密度、蓝藻密度的相关性最强,因其不受叶绿素a影响在水华定性方面较NDVI、PCI和MCI指数法更具优势。研究显示,PCAI构建原理简单,方法独特,提取蓝藻水华的结果较为可信,可推广使用。

控藻剂与小球藻联合控制蓝藻水华效果研究

以铜绿微囊藻为研究对象,将微囊藻水华池塘分隔成数块小区进行控藻剂药效测试,通过测定藻蓝蛋白评价不同控藻剂对蓝藻的控制水平。结果表明,几种控藻剂对蓝藻防效效果有差异,其中复合处理组4与小球藻组合在实验第1,3,7,12,15天处理后的藻蓝蛋白含量和浊度值显著低于对照组,且DO显著高于对照组。这表明该控藻剂与小球藻联合对蓝藻的防治效果较好,且对水体的DO影响不大,克服了目前主流控藻剂使用后容易造成DO骤降带来的生态问题。

C-藻蓝蛋白纳米微球的制备及体外抗脂多糖联合海水诱导急性肺损伤的作用机制研究

目的制备C-藻蓝蛋白纳米微球(CPC-NPs)并评价其对脂多糖(LPS)联合海水诱导急性肺损伤的体外作用机制。方法采用离子交联法,以CPC为药物、羧甲基壳聚糖(CMCS)为载体、CaCl2为交联剂制备CPC-NPs,对CPC-NPs进行基础表征。小鼠肺泡Ⅱ型上皮细胞MLE-12和巨噬细胞RAW264.7均分为7组:正常组(Con组),模型组(Mod组),空白NPs组,CPC-NPs 30、60、120、240μg/mL组。除Con组外其余各组均采用10μg/mL LPS和25%海水联合处理6 h,造模后各给药组加相应剂量药物处理24 h。检测MLE-12细胞中丙二醛(MDA)、总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)水平,B细胞淋巴瘤2(Bcl-2)、Bcl-2关联X蛋白(Bax)、胱天蛋白酶-3(caspase-3)蛋白和mRNA,以及CAT、谷胱甘肽S-转移酶(GST)mRNA表达水平;检测RAW264.7细胞中白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)、IL-6水平,NOD样受体热蛋白结构域相关蛋白3(NLRP3)、剪切的caspase 1(cleaved-caspase-1)蛋白及IL-1β、TNF-α、IL-6、诱导型一氧化氮合酶(iNOS)mRNA表达水平。结果制备的CPC-NPs粒径为(675.69±64.58)nm,Zeta电位为(-20.11±0.98)mV,多分散系数为0.455±0.010(n=3);包封率为35.60%,载药量为16.13%;形态为规则的球形;其中药物可持续释放30h以上。与Mod组比较,CPC-NPs各浓度组MLE-12细胞中T-AOC、SOD、CAT(除CPC-NPs 30μg/mL组外)、GSH-Px水平和CAT、GST mRNA表达水平以及Bcl-2/Bax蛋白比值和mRNA比值均显著升高,MDA水平和caspase-3蛋白及mRNA表达水平均显著降低(P<0.01或P<0.05)。与Mod组比较,CPC-NPs各浓度组RAW264.7细胞中IL-1β、TNF-α、IL-6水平和NLRP3、cleaved-caspase-1蛋白表达水平以及IL-1β、TNF-α、IL-6、iNOS mRNA表达水平均显著降低(P<0.01或P<0.05)。结论成功制备了具有肺靶向性和缓释性的CPC-NPs。CPC-NPs可以通过抗氧化应激及抑制细胞凋亡和炎症反应来缓解LPS联合海水诱导的急性肺损伤。

藻蓝蛋白对小鼠皮肤损伤的治疗效果

为探讨藻蓝蛋白(CPC)对小鼠皮肤损伤的治疗效果,将ICR小鼠分为正常对照组(Con)、模型组(Mod)、空白敷料组(BD)、藻蓝蛋白敷料组(CPC TDD)和藻蓝蛋白敷料+藻蓝蛋白腹腔注射组(CPC+ip.)5个处理组进行小鼠烫伤试验。结果表明,CPC TDD组和CPC+ip.组伤口愈合时间最短,可以降低血清中丙二醛(MDA)含量,提高超氧化物歧化酶(SOD)含量,降低血清中炎症因子TNF-α和IL-6的水平。藻蓝蛋白通过增强机体抗氧化能力,降低炎症因子水平,从而对皮肤损伤的愈合起到促进作用。

基于遥感影像的多方法评估氮元素对太湖水华影响

氮元素与太湖水华暴发有强相关性,是太湖水华暴发的重要因子.论文基于多源数据深入探讨了氮元素对太湖蓝藻水华暴发的影响机制.结果显示,氮元素通过营养盐释放和循环利用推动水华暴发,与蓝藻生长之间构成正反馈.高水温下,蓝藻生长与反硝化过程对硝态氮的竞争,削弱了反硝化微生物的脱氮效果,导致太湖水华持续化.相关性分析表明,不同形态氮与叶绿素a之间存在显著相关.论文从多层次、多角度解析氮元素与太湖水华暴发的关联机制,研究结果可为水体生态修复和水环境管理决策提供科学依据.

具尾蓝隐藻(Chroomonas caudata Geitler)研究──Ⅱ.藻蓝蛋白(Phycocyanin)的初步分析

初步分析了具尾蓝隐藻（ChroomonascaudataGeitler）的藻蓝蛋白，其吸收光谱为一双峰曲线，两个吸收峰分别为590nm和640nm。按A．N．Glazer等关于隐藻藻蓝蛋白分型的意见，具尾蓝隐藻的藻蓝蛋白属于Ⅱ型PC－645。

A novel phycocyanin-Chla/c_2-protein complex isolated from chloroplasts of Chroomonas placoidea

Nine pigment-protein complexes were separated and characterized from intact Chroomonasplacoidea chloroplasts by IEF. The bands Ⅰ-Ⅵ with their isoelectric points （pI） values from 4 to 6 were phycocyanin components; bands Ⅷ and Ⅸ （pI = 2.8-3.6） were chlorophyll-protein complexes. According to absorption and fluorescence spectra, band VII was designated as a novel phycocyanin-Chla/c2-protein complex （pI ≈ 3.4-3.7）. These results indicated that phycocyanin is structurally and functionally coupled with chlorophyll-protein complex in C. placoidea, and probably interacted with electrostatic force in combination.

Phycocyanin attenuates X-ray-induced pulmonary inflammation via the TLR2-MyD88-NF-κB signaling pathway

Phycocyanin (PC), a natural algal protein, is reported for having anti-oxidant and antiinfl ammatory properties. We investigated its ability to attenuate lung infl ammation in mice subjected to X-ray radiation. Male C57BL/6 mice were assigned to the control, total body irradiation, PC pretreatment, and PC treatment groups. Mice in the PC pretreatment group were gavaged with 200 mg/kg PC for 7 consecutive days before irradiation, and those in the PC treatment group were gavaged with 200 mg/kg PC for 7 consecutive days after irradiation. Lungs were collected on Day 7 after irradiation exposure. Hematoxylin and eosin staining of mouse lung sections showed considerable infl ammation damage 7 days after irradiation compared with the control lung but a reduction in pathological injury in the PC treatment group. Pretreatment or treatment with PC signifi cantly decreased levels of interleukin-6 and tumor necrosis factor-α in the lung, and also increased the relative mRNA expression of superoxide dismutase and glutathione. In vivo, PC signifi cantly reduced the expression of Toll-like receptor TLR2, myeloid diff erentiation primary response Myd88, and nuclear factor NF-κB, at both the transcriptional and translation level. Taken together, these data indicated that PC attenuated lung infl ammatory damage induced by radiation by blocking the TLR2- MyD88-NF-κB signaling pathway. Therefore, PC could be a protective agent against radiation-induced infl ammatory damage in normal tissues.

Alternative Methods for Analysis of Cyanobacterial Populations in Drinking Water Supplies: Fluorometric and Toxicological Applications Using Phycocyanin

The management of cyanobacteria and potential exposure to associated biotoxins requires the allocation of scarce resources across a range of freshwater resources within various jurisdictions. Cost effective and reliable methods for sample processing and analysis form the foundation of the protocol yielding reliable data from which to derive important decisions. In this study the utilization of new methods to collect, process and analyze samples enhanced our ability to evaluate cyanobacterial populations. Extraction of phycocyanin using the single freeze thaw method provided more accurate and precise measurements (CV 4.7% and 6.4%), offering a simple and cost-effective means to overcome the influence of morphological variability. In-vacuo concentration of samples prior to ELISA analysis provided a detection limit of 0.001 μg·L?1 MC. Fractionation of samples (?1) = ?0.279 + (1.368 ? Log PC (μg·L?1) while in an Aphanizomemon spp. dominant system Log MC (ng·L?1) = 0.385 + (0.449 ? Log PC (μg·L?1). These methods and sampling protocol could be used in other aquatic systems across a broader regional landscape to estimate the levels of microcystins.

Na^+/K^+-ATPase α-subunit in swimming crab Portunus trituberculatus: molecular cloning, characterization, and expression under low salinity stress

Na^＋/K^＋-ATPases are membrane-associated enzymes responsible for the active transport of Na^＋ and K^＋ ions across cell membranes, generating chemical and electrical gradients. These enzymes＇ α-subunit provides catalytic function, binding and hydrolyzing ATP, and itself becoming phosphorylated during the transport cycle. In this study, Na^＋/K^＋-ATPase α-subunit eDNA was cloned from gill tissue of the swimming crab Portunus trituberculatus by reverse-transcription polymerase chain reaction （RT-PCR） and rapid amplification of eDNA end methods. Analysis of the nucleotide sequence revealed that the eDNA had a full-length of 3 833 base pairs （bp）, with an open reading frame of 3 120 bp, 5＇ untranslated region （UTR） of 317 bp, and 3＇ UTR of 396 bp. The sequence encoded a 1 039 amino acid protein with a predicted molecular weight of 115.57 kDa and with estimated pI of 5.21. It was predicted here to possess all expected features of Na^＋/K^＋-ATPase members, including eight transmembrane domains, putative ATP-binding site, and phosphorylation site. Comparison of arnino acid sequences showed that the P. tritubereulatus α-subunit possessed an overall identity of 75%-99% to that of other organisms. Phylogenetic analysis revealed that this α-subunit was in the same category as those of crustaceans. Quantitative real-time RT-PCR analysis indicated that this α-subunit＇s transcript were most highly expressed in gill and lowest in muscle. RT-PCR analysis also revealed that α-subunit expression in crab gill decreased after 2 and 6 h, but increased after 12, 24, 48, and 72 h. In addition, α-subunit expression in hepatopancreas of crab decreased after 2-72 h. These facts indicated that the crab＇s Na^＋/K^＋-ATPase α-subunit was potentially involved in the observed acute response to low salinity stress.

Purification and Photodynamic Bioactivity of Phycoerythrin and Phycocyanin from Porphyra yezoensis Ueda

Phycoerythrin and phycocyanin were purified from Porphyra yezoensis Ueda with their bioactivity determined in this study. Continuous precipitation with ammonium sulfate at different concentrations(10%, 20%, 40% and 50%) increased the purity(A564:A280) of phycoerythrin to 1.49, 3.92 fold of the raw extract(0.38) and the purity(A615:A280) of phycocyanin to 0.70, 3.33 fold of the raw extract(0.21). Two more times of chromatography with hydroxylapatites finally made the purity of phycoerythrin and phycocyanin reach 5.50, 14.47 fold of the raw extract, and 5.10, 24.29 fold of the raw extract, respectviely. The yield of high purity phycoerythrin and phycocyanin were 0.21% and 0.09% of dried P. yezoensis blade, respectively. The photodynamic cytotoxic experiment showed that both phycoerythrin and phycocyanin inhibited the growth of liver tumor cells significantly. It was found that 250 mg L-1 purified phycoerythrin and phycocyanin inhibited the growth of hepatocellular carcinoma cells 24 h after laser-irradiation by 80% and 59%, respectively, and 100 mg L-1 purified phycoerythrin and phycocyanin induced the apoptosis of 31.54% and 32.54% of the cells, respectively, 8 h after photodynamic therapy. Oue findings demonstrated that P. yezoensis can serve as photosensitizer(phycoerythrin and phycocyanin) producer.

Interventional effect of phycocyanin on mitochondrial membrane potential and activity of PC12 cells after hypoxia/reoxygenation

BACKGROUND： Phycocyanin can relieve decrease of mitochondrial membrane potential through reducing production of active oxygen so as to protect neurons after hypoxia/reoxygenation. OBJECTIVE： To observe the effect of phycocyanin on activity of PC12 cells and mitochondrial membrane potential after hypoxia/reoxygenation. DESIGN： Randomized controlled study SETTING ： Cerebrovascular Disease Institute of Affiliated Hospital, Medical College of Qingdao University MATERIALS： The experiment was carried out at the Key Laboratory of Prevention and Cure for cerebropathia in Shandong Province from October to December 2005. PC12 cells, rat chromaffin tumor cells, were provided by Storage Center of Wuhan University; phycocyanin was provided by Ocean Institute of Academia Sinica; Thiazoyl blue tetrazolium bromide （MTT） and rhodamine 123 were purchased from Sigma Company, USA; RPMI-1640 medium, fetal bovine serum and equine serum were purchased from Gibco Company, USA. METHODS： ① Culture of PC12 cells： PC12 cells were put into RPMI-1640 medium which contained 100 g/L heat inactivation equine serum and 0.05 volume fraction of fetal bovine serum and incubated in CO2 incubator at 37℃. Number of cells was regulated to 4 × 10^5 L 1, and cells were inoculated at 96-well culture plate. The final volume was 100μL. ② Model establishing and grouping： Cultured PC12 cells were randomly divided into three groups： phycocyanin group, model control group and non-hypoxia group. At 24 hours before hypoxia, culture solution in phycocyanin group was added with phycocyanin so as to make sure the final concentration of 3 g/L , but cells in model control group did not add with phycocyanin. Cells in non-hypoxia group were also randomly divided into adding phycocyanin group （the final concentration of 3 g/L） and non-adding phycocyanin group. Cells in model control group and phycocyanin group were cultured with hypoxia for 1 hour and reoxygenation for 1, 2 and 3 hours; meanwhile, cells in non-hypoxia group were cultured with oxygen and were measured at 1 hour after hypoxia/reoxygenation. ③ Detecting items： At 1, 2 and 3 hours after reoxygenation, absorbance （A value） of PC12 cells was measured with MTT technique so as to observe activity and quantity of cells. Fluorescence intensity of PC12 cells marked by rhodamine 123 was measured with confocal microscope in order to observe changes of mitochondrial membrane potential. MAEN OUTCOME MEASURES： Comparisons between quantity and activity of PC12 cells and mitochondria membrane potential at 1, 2 and 3 hours after reoxygenation. RESULTS： ① Effect of phycocyanin on quantity and activity of PC12 cells： A value was 0.924±0.027 in adding phycocyanin group and 0.924±0.033 in non-adding phycocyanin group. A value was lower in model control group and phycocyanin group than that in non-hypoxia group at 1, 2 and 3 hours after reoxygenation （0.817±0.053, 0.838±0.037, 0.875±0.029; 0.842±0.029, 0.872±0.025, 0.906±0.023, P 〈 0.05）. A value was higher in phycocyanin group than that in model control group at 1, 2 and 3 after culture （P 〈 0.05）. With culture time being longer, A value was increased gradually in phycocyanin group and model control group after reoxygenation （P 〈 0.05）. ~ Effect of phycocyanin on mitochondrial membrane potential of PC12 cells： Fluorescence intensity was 2.967±0.253 in adding phycocyanin group and 2.962±0.294 in non-adding phycocyanin group. Fluorescence intensity was lower in model control group and phycocyanin group than that in non-hypoxia group at 1, 2 and 3 hours after hypoxia/reoxygenation （1.899±0.397, 2.119±0.414, 2.287±0.402; 2.191±0.377, 2.264±0.359, 2.436±0.471, P 〈 0.05）; but it was higher in phycocyanin group than that in model control group at 1, 2 and 3 after reoxygenation （P 〈 0.05）. With culture time being longer, fluorescence intensity was increased gradually in phycocyanin group and model control group after reoxygenation （P 〈 0.05）. CONCLUSION： Phycocyanin and reoxygenation can protect PC12 cells after hypoxia injury through increasing mitochondrial membrane potential and cellular activity, and the effect is improved gradually with prolonging time of reoxygenation.

Temporal and Spatial Variations of Abundance of Phycocyaninand Phycoerythrin-Rich Synechococcus in Pearl River Estuary and Adjacent Coastal Area

Three surveys were carried out in Pearl River Estuary and adjacent coastal area in May, August, and November, 2013, to investigate the temporal and spatial variations of abundance of phycoerythrin-rich Synechococcus(PE-rich SYN) and phycocyanin-rich Synechococcus(PC-rich SYN). The effects of environmental factors on the alternation of the different Synechococcus groups were also elucidated. PE-rich SYN was detected in three surveys, whereas PC-rich SYN was detected in May and August, but not in November. The highest abundances of PE-rich SYN and PC-rich SYN were recorded in August and May, with mean values of 74.17×103 and 189.92×103 cells m L-1, respectively. From May to November, the relative abundance of PE-rich SYN increased, whereas that of PC-rich SYN declined. PE-rich and PC-rich SYN presented similar horizontal distributions with high abundance in the southern estuary in May, and in the western estuary in August. The abundances of PE-rich and PC-rich SYN were high at 27–32℃and salinity of 10–20. PC-rich SYN was not detected at < 24℃, and PC:PE-rich SYN decreased in abundance with salinity increase. When less than 20 mg L-1, suspended particulate matter(SPM) was helpful for Synechococcus growth. PE-rich SYN decreased in abundance when the concentration of dissolved inorganic nitrogen increased in May and November, and the concentration of phosphate increased in November. However, PC-rich SYN abundance and nutrients showed no correlation. Principal component analysis and regression analysis indicated that PE-rich SYN significantly correlated with the principal components that were affected by environmental factors.

The Stability of C-phycocyanin Doped Silica Biomaterials in UV Irradiation

The synthesized C-phycocyanins （C-PCs） doped silica biomaterials were characterized by the SEM and BET surface area analysis measurement. The morphology of C-PCs doped silica biomaterials indicates that the surface of the silica cluster is formed by a great number of silica particles with an average size of between 30 and 40 nm. Silica itself is a porous structure with the average pore diameter of 2.95 nm. Pores with their diameter less than 5 nm account for 84.07%. In addition, the C-PCs can be utilized as a fluorescent protein probe to monitor influence of the protein encapsulation and to study matrix and protein interaction and stability of protein in silica matrix. Application of protein encapsulation silica materials requires biomolecules to keep bioactivity and stability on potentially unfavorable industrial conditions. The C-PCs in solution or in silicate matrix irradiated by ultraviolet ray can result in photobleaching, whereas the protein in the silica is less affected. The measured photodamage rate constant of C-PCs in buffer solution is 25 times faster than that of C-PCs in silica matrix. However, the lifetime of C-PCs in silica matrix or phosphate buffer is unaffected. These studies suggest that entrapment of C-PCs into silica matrixes not only can maintain their biological activity but also noticeably improve their photostability.

ATP Synthase β-subunit Abnormality in Pancreas Islets of Rats with Polycystic Ovary Syndrome and Type 2 Diabetes Mellitus

This study investigated the abnormal expression of ATP synthase β-subunit（ATPsyn-β） in pancreas islets of rat model of polycystic ovary syndrome（PCOS） with type 2 diabetes mellitus（T2DM）,and the secretion function changes after up-regulation of ATP5 b.Sixty female SD rats were divided into three groups randomly and equally.The rat model of PCOS with T2 DM was established by free access to the high-carbohydrate/high-fat diet,subcutaneous injections of DHEA,and a single injection of streptozotocin.The pancreas was removed for the detection of the ATPsyn-β expression by immunohistochemical staining,Western blotting and reverse transcription-PCR（RT-PCR）.The pancreas islets of the rats were cultured,isolated with collagenase Ⅴ and purified by gradient centrifugation,and the insulin secretion after treatment with different glucose concentrations was tested.Lentivirus ATP5 b was successfully constructed with the vector of GV208 and transfected into the pancreas islets for the over-expression of ATPsyn-β.The insulin secretion and intracellular ATP content were determined after transfection of the PCOS-T2 DM pancreas islets with Lenti-ATP5 b.The results showed that the expression of ATPsyn-β protein and m RNA was significantly decreased in the pancreas of PCOS-T2 DM rats.The ATP content in the pancreas islets was greatly increased and the insulin secretion was improved after the up-regulation of ATPsyn-β in the pancreas islets transfected with lenti-ATP5 b.These results indicated that for PCOS,the ATPsyn-β might be one of the key factors for the attack of T2 DM.

Isolation and Characterization of C-phycocyanin from Spirulina Platensis

The isolation of biliproteins from the Spirulina platensis cultured in southern China was accomplished with gel filtration on Sephacryl S 200 and chromatography on hydroxylapatite. The spectrophotometry, isoelectric point, and amino acid composition of C phycocyanin were determined, respectively.