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。

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。

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.

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.

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.

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.

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.

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

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IRON IONS INCREASE THE THERMOSTABILITY OF PHYCOCYANIN OF SPIRULINA MAXIMA

A spectral method to investigate the effect of Fe3+, Fe2+ on the thermostability ofphycocyanin (PC) of Spirulina maxima showed that iron ions prevent decrease of visible light absorbanceand fluorescence intensity of PC. Increase in denaturation temperature caused by Fe3+ was observed bythe micro - differential scanning calorimetric method. All results showed iron ions maintain the aggrega-tion stability of the PC. The absorption spectrum of phycocyanobilin (PCB, a prosthetic group of PC) withFe3+ in chloroform was quite different from that of free PCB.

EFFECTS OF PHYCOCYANIN ON EXPRESSION OF CytC mRNA AND CASPASE-3 mRNA AFTER FOCAL CEREBRAL ISCHEMIA/REPERFUSION IN RATS

Objective To study the effects of phycocyanin on the expression of Cytochrome C (CytC)genes and Caspase-3 genes after focal cerebral ischemia/reperfusion in rats. Methods A rat middle cerebral ar-tery occlusion (MCAO)/reperfusion model was produced using the intraluminal filament method. The rats were di-vided into three groups: sham operation group, model control group and phycocyanin group. After MCAO, the neu-robehavioral testing of all rats was made. The infarction area was evaluated with the method of 2,3,7-triphenyltet-razolium chloride (TTC) staining. The expression of CytC mRNA and Caspase-3 mRNA were determined by in situhybridization. Results In the sham operation group and the model control group, there was only a few CytC-positive cells were seen in the normal cerebral tissue. In the model control group, the upregulation of CytC mRNAbegan 6h after ischemia, reached a maximum at 12h (cortex) -24h (striatum) , then subsided gradually, but stillin high level. In the phycocyanin group, CytC-positive cells were also mainly in cortex and striatum, but the numberof the cells was significantly lower than the number of the model control group. The time-phase pattern of CytCmRNA in the phycocyanin group was similar to the pattern of the model control group. In the sham operation groupand the model control group, there was only a few Caspase-3-positive cells were seen in the normal cerebral tissue.In the model control group, the upregulation of Caspase-3 mRNA began 6h after ischemia, reached a maximum at24h and subsided at 48h, but still in high level. In the phycocyanin group, Caspase-3-positive cells were also mainlyin the penumbral area, but the number of the cells were significantly lower than the number of the model controlgroup. The time-phase pattern of Caspase-3 mRNA in the phycocyanin group was similar to the pattern of the modelcontrol group. Conclusion The over-expression of CytC mRNA and Caspase-3 mRNA might play a key role inischemic cerebral injury after MCAO. Phycocyanin could inhibit the over-expression of CytC mRNA and Caspase-3mRNA in the cerebral cortex, and might play an important role in the protection of ischemic neurons.

Physicochemical degradation of phycocyanin and means to improve its stability:A short review

The cyanobacterium Arthrospira platensis,spirulina,is a source of pigments such as phycobiliprotein and phycocyanin.Phycocyanin is used in the food,cosmetics,and pharmaceutical industries because of its antioxidant,anti-inflammatory,and anticancer properties.The different steps involved in extraction and purification of this protein can alter the final properties.In this review,the stability of phycocyanin(pH,temperature,and light)is discussed,considering the physicochemical parameters of kinetic modeling.The optimal working pH range for phycocyanin is between 5.5 and 6.0 and it remains stable up to 45℃;however,exposure to relatively high temperatures or acidic pH decreases its half-life and increases the degradation kinetic constant.Phycobiliproteins are sensitive to light;preservatives such as mono-and disaccharides,citric acid,or sodium chloride appear to be effective stabilizing agents.Encapsulation within nano-or micro-structured materials such as nanofibers,microparticles,or nanoparticles,can also preserve or enhance its stability.

The phycocyanin-chlorophyll-protein complexes isolated from Chroomonas placoidea

An active photosystem(PS)Ⅱparticle and two light-harvesting complexes,as well as their subcomplexes that have not been reported previously,were isolated from a cryptophyte Chroomonas placoidea by Triton X-100 sucrose density gradient centrifugation.The fluorescence spectra revealed that there were efficient energy couplings between phycocyanin(PC645)and chlorophyll(Chl)within both zonesⅢandⅣof the gradient,which were designated respectively as light-harvesting complex and PSⅡparticles whose size was 15-20 nm according to negative staining in electron microscopy.When the two complexes were further resolved into sub-complexes,the energy coupling was retained in the core PSⅡcomplex(named as zoneⅣ-2 of the sucrose gradient),which contained almost no outer antenna pigment Chl c.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)showed that the PC645 components appeared in Chl-containing protein complexes were mainly the β subunit with molecular weight of 20 kDa.These results demonstrate that PC645 in this cryptophyte was structurally but preferentially combined with the light-harvesting complex and PSⅡcore.The excitation energy absorbed by PC645 could be directly transferred to Chl a(especially the long wavelength of Chl a)in the PSⅡreaction center or via the Chl a/c-protein complex.The β subunit corresponded to the terminal fl uorescence emission and might play an important role in transmitting energy from PC645 to the Chl-protein complex.The results will help in elucidating the architecture and function of the energy transfer system comprising phycobiliproteins and Chl-protein complexes in cryptophytes.

Telomere Protective Effects of a Cyanobacteria Phycocyanin against Blue Light and UV Irradiations: A Skin Anti-Aging and Photo-Protective Agent

Background: Cyanobacteria phycocyanins (Cps) have already shown powerful antioxidant properties. In human cells submitted to oxidative stress the telomeres length decrease, the expression of progerin and the activity of mTOR are increased. At our knowledge, there is no published data on Cps correlated with ultraviolet radiation (UV) and blue light effects in human cells regarding telomeres’ length, progerin expression or mTOR1 complex activity. Objectives: In this study, we sought to assess 1) telomeres’ length in newborn human fibroblasts exposed to UV and blue light;2) progerin production in mature human normal fibroblasts exposed to UV;3) mTOR1 activation in adult human normal keratinocytes exposed to UV, analyzing the activity of a Cyanobacteria phycocyanin (Cp) in these in vitro models. Materials and Methods: Human skin fibroblasts or human normal keratinocytes were cultured—in the absence or in the presence of Cp and submitted to UVB + UVA and blue light irradiations. Telomeres’ length, progerin expression and mTOR1 activity were then assessed by molecular biology and immuno-enzymatic methods. Results: In cultured fibroblasts exposed to irradiations and treated by Cp, telomeres’ shortage and progerin expression were lower compared to irradiated untreated cells. In cultured keratinocytes treated by Cp and exposed to irradiations, the mTOR activity was lower compared to irradiated untreated cells. Conclusions: In these in vitro studies on human skin fibroblasts and on normal human keratinocytes, the cyanobacteria phycocyanin (Cp) showed a decrease of damages induced by UV and blue light expressed by telomeres preservation and downregulation of progerin expression and of mTOR activity, thus showing skin anti-aging and photo-protective potential.