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排序方式: 共有237条查询结果,搜索用时 31 毫秒
1.
电转化法转化钝顶螺旋藻转化条件的研究 总被引:2,自引:0,他引:2
确定了电转化法转化钝项螺旋藻S6-4的转化条件。无论受体是藻丝还是单细胞/藻丝段,钝项螺旋藻S6-4在对数生长期内,半致死电场强度无显著差别。实验表明以对数中期的螺旋藻用于转化为宜。当脉冲时间是5.0ms时,藻丝受体和单细胞/藻丝段受体的半致死电场强度分别是3.75—5.0kV/cm和3.1—4.4kV/cm,而电击缓冲液分别是1.0mmol/L HEPES(pH7.5)缓冲液和含有0.5mol/L蔗糖的1.0mmol/L HEP—ES(pH7.5)缓冲液。本文的研究结果为螺旋藻转化及外源基因表达提供了实验基础。 相似文献
2.
Hareesh Iyer Paul Grandgeorge Andrew M. Jimenez Ian R. Campbell Mallory Parker Michael Holden Mathangi Venkatesh Marissa Nelsen Bichlien Nguyen Eleftheria Roumeli 《Advanced functional materials》2023,33(40):2302067
Since the 1950s, 8.3 billion tonnes (Bt) of virgin plastics have been produced, of which around 5 Bt have accumulated as waste in oceans and other natural environments, posing severe threats to entire ecosystems. The need for sustainable bio-based alternatives to traditional petroleum-derived plastics is evident. Bioplastics produced from unprocessed biological materials have thus far suffered from heterogeneous and non-cohesive morphologies, which lead to weak mechanical properties and lack of processability, hindering their industrial integration. Here, a fast, simple, and scalable process is presented to transform raw microalgae into a self-bonded, recyclable, and backyard-compostable bioplastic with attractive mechanical properties surpassing those of other biobased plastics such as thermoplastic starch. Upon hot-pressing, the abundant and photosynthetic algae spirulina forms cohesive bioplastics with flexural modulus and strength in the range 3–5 GPa and 25.5–57 MPa, respectively, depending on pre-processing conditions and the addition of nanofillers. The machinability of these bioplastics, along with self-extinguishing properties, make them promising candidates for consumer plastics. Mechanical recycling and fast biodegradation in soil are demonstrated as end-of-life options. Finally, the environmental impacts are discussed in terms of global warming potential, highlighting the benefits of using a carbon-negative feedstock such as spirulina to fabricate plastics. 相似文献
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了建立螺旋藻外源基因表达体系,首先必须选择螺旋藻抗性基因。本实验选用三种抗生素进行敏感性研究,实验结果表明:螺旋藻对这三种抗生素的敏感性有明显差异,它们对螺旋藻生长的抑制作用依次为:氯雷素>链霉素>氨苄青霉素。氯霉素对螺旋藻生长的抑制作用与氯霉素的浓度和作用时间呈正相关。600mg/L氯霉素处理48h就对螺旋藻有明显的致死作用,致死率分别为:48h为17。51%、144h为68.67%;400mg/L的氯霉素:48h至死率为1.96%、144h为49.76%;200mg/L以下低浓度的氯霉素对螺旋藻的抑制作用需要较长时间,144h才具有明显的致死作用,致死率为19.24%。 相似文献
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Elvis Maujean Stéphane Desobry Guillaume Gillet Nicolas Poupard Isabelle Desjardins-Lavisse Sylvie Desobry-Banon 《International Journal of Food Science & Technology》2021,56(5):2443-2451
In this study, preservation of spirulina using the new pressurised cryogenic nitrogen technology (PCN) was compared to classical methods used in laboratories and industry. Spirulina morphology was better preserved by PCN compared to unpressurised cryogeny and classical freezing at −20 °C that led to cells fragmentation. A 25% loss of Phycocyanin-C content against 60% were measured after 98 days storage for 6-Bar PCN process and frozen samples, respectively. The Total AntiOxidant Power (PAOT Liquid Technology®) was used for determination of total antioxidant and oxidant power of spirulina extracts. PAOT value of PCN samples was 50% higher than the frozen sample. From ABTS measurements on PCN spirulina fractions sonicated or not, it was suggested that pressurisation at 6 bars allowed a better preservation of free antioxidants (outside the cells) due to replacement of oxygen by nitrogen in the frozen beads. After dehydration, phycocyanin-C content variation during storage at 20 °C and 33% RH showed higher loss for freeze-dried spirulina treated at 0 compared to 6 Bars. 相似文献
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螺旋藻多糖提取新工艺的研究 总被引:36,自引:2,他引:36
提取螺旋藻多糖的传统工艺存在着流程长,操作复杂,有机溶剂消耗大等问题。采用三氯乙酸(TCA)法代替Sevag法去除蛋白质,使改进后的提取工艺中蛋白质去除率增加,多糖损失率降低,流程缩短。通过用DEAE-Speharose和Sephadex-G50柱的分离纯化得到2个多糖组分。经测定,其相对分子质量分别为Mr1=12600,Mr2=16600。组分1的单糖组成:D-葡萄糖、D-甘露糖、D-半乳糖和葡萄糖醛酸;组分2的单糖组成:D-葡萄糖、D-木糖、L-鼠李糖和葡萄糖醛酸。 相似文献
9.
Simultaneous production of C‐phycocyanin and extracellular polymeric substances by photoautotrophic cultures of Arthrospira platensis
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10.
对以石油醚为溶剂从螺旋藻中提取β-胡萝卜素的工艺条件进行了研究。实验结果表明,最佳提取条件为:固液比130,提取时间50min,提取温度70℃,且一次性提取有较高的提取率,其它色素在本实验条件下对提取β-胡萝卜素的干扰较小 相似文献