Storage quality of powdered cyanobacterium —Spirulina platensis

The cyanobacteriumSpirulina platensis, produced at the Central Food Technological Research Institute, was dried using the cross-flow technique and subsequently subjected to packaging studies. The moisture sorption studies at 27 °C indicated a critical moisture content of 12.5%, corresponding to 56% relative humidity (RH). The product was packed in pouches made of polypropylene (37 μm thick) and a laminate of metallized polyester with low-density polyethylene and was stored at: (1) 38 °C, 90% RH (accelerated condition) or (2) 27 °C, 65% RH (standard condition). Periodically throughout its storage under these conditions, the product was analysed for its content of moisture, protein, ash and fat. In addition, determinations were made of the changes in the constituents carotene, phycocyanin and allophycocyanin.     

The lipids of the alga Spirulina

The blue-green alga, Spirulina maxima, examined in the form of a spray-dried powder, contains 11% of lipid, which has been analysed in detail with a view to establishing both the classes of lipid present and their fatty acid profiles. The dominant lipids are mono-, di- and probably higher galactosyldiglycerides and phosphatidyl glycerol. Unlike other algae, Spirulina synthesises cis-6-cis-9-cis-12 octadecatrienoic acid in contrast to its 9–12–15 isomer.     

Use of blue-green micro-seaweed Spirulina platensis for the correction of lipid and hemostatic disturbances in patients with ischemic heart disease

Changing in lipid spectrum, immunological state and coagulation in the 68 patients with IHD and atherogenic dyslipidemia who were taking biomass microalga Spirulina platensis was investigated. Modification of traditional plan of therapy of IHD when adding microalga Spirulina p. influences correcting effect to cascade procoagulation and immunopathological reactions, characteristic of atherosclerosis process.     

Cr(III)在钝顶螺旋藻中的生物富集及其对螺旋藻生长的影响

本实验研究了钝顶螺旋藻对Cr(III)的吸收和生物转化以及Cr(III)对钝顶螺旋藻的生长影响,用ICP-MSHPLC对无机Cr(III) 经钝顶螺旋藻吸收后的存在价态进行了分析。结果表明,钝顶螺旋藻对Cr(III)具有良好的富集和生物转化能力,在本实验中总铬富集量可达到173.17mg/g,有机化程度可高达96.99%。ICP-MS-HPLC 分析结果表明没有有毒的Cr(VI)的产生。此外,干重测定结果显示低浓度的Cr(III) (< 234.38 × 10-6g/g)促进钝顶螺旋藻的生长,高浓度的Gr(Ⅲ)(> 234.38 × 10-6g/g)则抑制共生长,并导致钝顶螺旋藻形态异常。在一定范围内钝顶螺旋藻能高效富集Cr(III),可作为安全营养的保健食品;钝顶螺旋藻抗高Cr(III)压,吸附高浓度Cr(III)的能力使其可用于环境中Cr(III)污染的去除。     

螺旋藻食用安全性的研究

为了解螺旋藻的食用安全性，对螺旋藻进行了食品安全性毒理学评价。结果：骨髓微核实验中３个试验组的微核细胞率与阴性对照组相比，Ｐ值均大于０．０５，无显著性差异；Ａｍｅｓ试验的致突变率小于２，为阴性；小鼠精子畸形试验证实螺旋藻不引起小鼠精子畸形。试验结果表明螺旋藻ＬＤ５０大于１００００ｍｇ／ｋｇＢＷ，属无毒，是安全的食品。     

螺旋藻液抗诱变作用的实验研究

目的:探讨螺旋藻液对环磷酰胺诱变因子的抗诱变作用。方法:采用作为模型生物蚕豆根尖细胞微核率变化和染色体畸变技术。结果:表明螺旋藻提取液可明显抑制环磷酰胺诱导蚕豆根尖细胞微核和染色体畸变的形成,各剂量组与对照组相比有显著差异。用各剂量螺旋藻液处理后,根尖细胞微核率和染色体畸变率低于相应的阳性对照组,并且螺旋藻液低于1g/L时,抑制细胞中微核和染色体畸变的形成与螺旋藻液的剂量呈明显的剂量关系。结论:适当剂量的螺旋藻液对环磷酰胺诱变因子的诱变作用呈明显的抑制效应。      

螺旋藻培养条件研究

对影响螺旋藻生长的ｐＨ值、营养物质、微量元素及稀土元素等因素进行研究。在最适ｐＨ值范围和优化配方的碳、氮源浓度及比例以及微量元素与稀土元素含量的条件下,获得了比较理想的培养结果。     

螺旋藻的光生物反应器高密度培养

利用自制的光生物反应器对螺旋藻的生长进行了研究。结果表明 :光照强度和液体循环速度对藻体细胞的生长有极显著的影响 ,培养温度对生长有显著的影响 ;通过流加和碳源的供给形式的改变等培养条件和培养工艺的改进使藻体的生长速率、生物量产率和生物量产量分别达到了 0 .4 1 1 /d、3 2 .2 5g/m2 · d和 3 .93 g/L的水平 ,最大生长速率达到了0 .566/d。     

钝顶螺旋藻藻蓝蛋白的脉冲超声辅助提取技术

探讨钝顶螺旋藻藻蓝蛋白的脉冲超声辅助提取方法,并将脉冲超声辅助提取技术与传统提取方法——冻融法进行了对比。以钝顶螺旋藻为原料,采用脉冲超声辅助提取技术提取藻蓝蛋白,选定料液比、提取全程时间、循环泵转速、超声功率、超声发出时间和超声间歇时间作为参考因素,进行单因素和正交试验,优化得到的脉冲超声辅助提取最优工艺参数为:超声全程时间90min、超声功率1400W、超声发出时间6s、超声间歇时间9s、循环泵转速12r/s、提取温度20℃,当投料量为20g时,藻蓝蛋白的提取得率为13.45%,比冻融提取法高10.26%。这表明脉冲超声辅助提取法是一种高效分离钝顶螺旋藻藻蓝蛋白的方法。     

鄂尔多斯钝顶螺旋藻毒性评价

为探讨鄂尔多斯钝顶螺旋藻（Spirulina platensis）毒性状况,评价其摄入的危险性,该研究开展了钝顶螺旋藻急性毒性试验、小鼠骨髓细胞微核试验、Ames试验和小鼠精子畸形试验。结果表明,鄂尔多斯钝顶螺旋藻对雌雄小鼠经口最大耐受剂量（MTD）均大于20 g/kg体质量,小鼠未发生突变,小鼠骨髓嗜多染红细胞的微核率没有出现明显变化,对小鼠精子畸形发生率也未产生明显影响,检测结果均呈阴性,可以证明鄂尔多斯钝顶螺旋藻无急性毒性。     

钝顶螺旋藻藻蓝蛋白稳定性研究

从钝顶螺旋藻藻粉中分离纯化藻蓝蛋白,对其稳定性进行全面考察.实验结果表明,钝顶螺旋藻藻蓝蛋白溶液在低于40℃,pH4～8范围内能保持较高的活性,光照、反复冻融使藻蓝蛋白溶液的稳定性明显下降,0.5 mol/L～2 mol/L的NaCl起到稳定藻蓝蛋白的作用.藻蓝蛋白干粉在60℃、湿度为(75±5)％的条件下,活性不变,且10d后增重不超过5％;4 500 lx光强使藻蓝蛋白干粉活性显著降低.因此,长期保存藻蓝蛋白以干粉为宜,在低于60℃的弱光低湿环境中保存.     

超声-微波协同提取螺旋藻中的叶绿素

研究了超声-微波协同提取螺旋藻中叶绿素的工艺。通过单因素试验确定了影响提取叶绿素的主要因素及最佳水平范围,通过正交试验确定的最佳提取工艺为提取温度55 ℃,超声提取时间300 s,料液比1∶14（g∶mL）。在此最佳条件下,螺旋藻中叶绿素的总提取率为1.141%。     

钝顶螺旋藻藻蓝蛋白的提取工艺研究

为了研究钝顶螺旋藻藻蓝蛋白提取工艺的最佳条件,本文以钝顶螺旋藻干粉为原料,探讨高速匀浆法提取藻蓝蛋白过程中的各因素对其得率和产品纯度的影响。通过单因素与正交试验,确定最佳提取条件。结果表明:采用pH 7.0的PBS缓冲液为提取溶剂时,藻蓝蛋白得率最高为157.75 mg/g。经优化,当缓冲液溶剂添加量20倍,提取温度30℃,分3次匀浆提取共40 min时藻蓝蛋白得率达213.32 mg/g。比较乙醇沉淀法、酸沉淀法和盐沉淀法对藻蓝蛋白回收率的影响,结果表明采用50%的硫酸铵沉淀法藻蓝蛋白回收率达97.10%,藻蓝蛋白的纯度最高。采用高速匀浆法处理提取藻蓝蛋白,采用30%和50%分步盐析回收藻蓝蛋白,以本方法可获得纯度0.7以上的藻蓝蛋白239.70 mg/g干粉。经紫外可见光谱扫描显示,提取的藻蓝蛋白与藻蓝蛋白标品光谱特征一致。     

Functional characterization of pressurized liquid extracts of Spirulina platensis

Three different parameters (temperature, solvent, and extraction time) were studied regarding to pressure liquid extraction (PLE) of antioxidant and antimicrobial compounds from Spirulina platensis. Two different antioxidant methods, β-carotene bleaching method and DPPH^• (2,2-Diphenyl-1-picrylhydrazyl hydrate) free radical scavenging assay, were used to determine the optimal PLE conditions for antioxidants extraction. The selected conditions were as follows: extraction temperature equal to 115 °C, extraction time equal to 15 min and ethanol as extracting solvent. The main antioxidant compounds found in this extract were identified as zeaxanthin, a myxoxanthophyll-like compound and very polar phenolic compounds. Moreover, antimicrobial activity of different PLE fractions was tested against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 11775, Candida albicans ATCC 60193, and Aspergillus niger ATCC 16404. Data obtained showed the hexane and petroleum ether extracts were slightly more active than ethanolic extracts. As for water extracts, none of them were active against the microorganisms tested. Data indicated that both 115 and 170 °C were the best extraction temperatures conditions in order to optimize the extraction of antimicrobial compounds, whereas 9 min was the optimal extraction time. Besides, C. albicans was the most sensitive microorganism to all Spirulina PLE extracts.     

螺旋藻抗突变作用的探讨

为探讨螺旋藻抗突变作用的机理,用钝枯螺旋藻（SPG）为受试物,用3种不同的给予方法观察其拮抗由黄曲霉毒素（AFB1）所致的TA98菌株突变的作用。结果表明：SPG在较低浓度（40mg/皿）即可通过抑制AFB1对TA98的致突变作用,使突变菌落数明显减少;当SPG达到较高的浓度（100mg/皿）时,还可通过直接灭活AFB1的方式抑制AFB1的致突变作用。其可能机制是由于SPG中含有胡萝卜素、Vitc和葡萄糖醛酸等成分。前两者都已被证实具有抗突变和清除自由基的功能,而葡萄糖醛酸则可与AFB1结合使其灭活。结果还显示,SPG不能抑制AFB1引起的已突变的TA98菌株的突变表达。     

螺旋藻挂面的生产

介绍螺旋藻挂面的生产配方,操作要点,产品质量标准及保持挂面绿色的经验.     

Environmental impact of phycocyanin recovery from Spirulina platensis cyanobacterium

Multifunctional extracts from Spirulina platensis are suggested as food additives, due to their high content in functional ingredients and specifically phycocyanin. The recovery of phycocyanin from the microalgal biomass is performed by using ultrasounds and polar solvents such water, ethanol or buffer. The application of drying pretreatment in combination with the use of different solvents presents variation in the yields, affecting the actual recovery of the protein and hence the environmental impact of the production of 1 kg phycocyanin. Life cycle analysis on the recovery techniques for the isolation of the desired phycocyanin was performed in order to evaluate the selected extraction processes' sustainability. Drying exhibited increased environmental footprint due to the energy demand, while at the same time affecting not only the yielding but also the quality of the extracts. The use of aqueous solvents can lead to an environmental and efficient extraction, replacing organic solvent systems sufficiently.Industrial relevancePhycocyanin is a pigment-protein complex which is used into various food products to enhance their nutritional qualities acting as food colorant, antioxidant and emulsifier, which can sufficiently replace or reduce the use of synthetic additives. For the effective recovery of phycocyanin, the nutrient should be extracted from the microalgae biomass of Spirulina platensis. The steps to achieve that include the cultivation and harvesting of the microalgae, the drying of the biomass if necessary and the extraction process. However, these steps are resource and energy demanding processes which can affect the environmental footprint and the cost of the final product. Looking for more efficient practices combinations of materials (wet or dried biomass) and solvents (water, buffer and ethanol), which are currently used industrially, were examined in order to evaluate and suggest the most sustainable production line for phycocyanin.     

两种螺旋藻剂型的体外模拟消化研究

为探究两种剂型的螺旋藻营养物质和功能活性在消化过程中的变化,以螺旋藻粉剂和片剂为试验材料,经水解、酸解、高温及高压蒸汽等处理后进行体外模拟消化研究。结果表明：经口胃肠连续消化后,高压蒸汽处理的螺旋藻粉剂游离氨基酸释放效果最佳,是酸解处理（最差）的2.25倍。高温处理的螺旋藻粉剂可溶性蛋白释放效果最佳,比对照组（最差）提高了1.75倍。酸解和高温处理后的粉剂可溶性糖和还原糖释放效果较好,水解处理的螺旋藻片剂游离氨基酸、可溶性蛋白、可溶性多糖和还原糖释放较好;螺旋藻的游离氨基酸主要在胃肠消化后释放,可溶性多糖主要在肠消化后释放;酸解处理的粉剂抗氧化效果较好,水解处理的片剂抗氧化效果较好,且在口胃肠连续消化后螺旋藻抗氧化效果发挥最佳。