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Xiangyuan Deng Song Qin Yichen Zhang Peng Jiang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(10):1486-1492
BACKGROUND: Previously, tachyplesin gene (tac) has been successfully transferred into Undaria pinnatifida gametophytes using the method of microprojectile bombardment transformation. The objectives of this study were to compare and evaluate the performance of bubble‐column and airlift bioreactors to determine a preferred configuration of bioreactor for vegetative propagation of transgenic U. pinnatifida gametophytes, and to then investigate the influence of light on vegetative propagation of these gametophytes, including incident light intensity, photoperiod and light quality to resolve the problems of rapid vegetative propagation within the selected bioreactor. RESULTS: Experimental results showed that final dry cell density in the airlift bioreactor was 12.7% higher than that in the bubble‐column bioreactor under the optimal aeration rate of 1.2 L air min?1 L?1 culture. And a maximum final dry cell density of 2830 mg L?1 was obtained within the airlift bioreactor using blue light at 40 µmol m?2 s?1 with a light/dark cycle of 14/10 (h). Polymerase chain reaction (PCR) analysis indicated that genes (bar and tac) were not lost during rapid vegetative propagation within the airlift bioreactor. CONCLUSION: The airlift bioreactor was shown to be much more suitable for rapid vegetative propagation of transgenic U. pinnatifida gametophytes than the bubble‐column bioreactor in the laboratory. The use of blue light allows improvement of vegetative propagation of transgenic U. pinnatifida gametophytes. Copyright © 2009 Society of Chemical Industry 相似文献
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基质固相分散-高效液相色谱法测定山楂中的有机酸 总被引:1,自引:0,他引:1
研究采用基质固相分散处理、高效液相色谱法测定山楂中的有机酸.以ZORBAX Stable Bound(4.6×50mm,1.8μm)快速分离柱为固定相,0.01mol/L NaH2PO4(pH2.98)和乙腈(体积比为98:2)为流动相,流速为2.0ml/min,柱温25℃,检测波长210nm.方法回收率为94%~98%;相对标准偏差为2.1%~3.0%;检出限为100~200μg/L.色谱分离时间不超过3.0min.并用于实际样品中有机酸分析,结果令人满意. 相似文献
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Di Jiang Ying Bai Baoyu He Yue Sui Xiufang Dong Chenxu Yu Hang Qi 《Journal of texture studies》2020,51(2):333-342
The effects of phlorotannin extracts (PTE) (from sporophyll of Undaria pinnatifida) added at different concentration (0, 1.6, 8, and 40 mg/g protein) with and without ultraviolet A (UVA) irradiation treatment on gel properties of mackerel (Scomberomorus niphonius) mince (MM) were investigated. The results indicated that both the breaking force and water-holding capacity (WHC) of the MM gel increased with addition of PTE, and the highest breaking force and WHC were observed with 40 mg/g PTE under UVA irradiation. Low-field nuclear magnetic resonance revealed that free water significantly decreased in this PTE-MM gel as well. UVA irradiation treatment led to reduction of total sulfhydryls and free amines in the PTE-MM gel, indicating more cross-linking between proteins. Electrophoresis results indicated that myosin heavy chains were aggregated in the UVA-treated PTE-MM gel. The microstructure of the UVA-treated PTE-MM gel showed that protein formed more evenly distributed cross-linked structures and was more compact than the untreated control gel. As a conclusion, PTE addition with UVA irradiation is shown to improve gelling properties of mackerel mince. 相似文献
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Chlorogenic Acid from Hawthorn Berry (Crataegus pinnatifida Fruit) Prevents Stress Hormone‐Induced Depressive Behavior,through Monoamine Oxidase B‐Reactive Oxygen Species Signaling in Hippocampal Astrocytes of Mice
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Enzyme assisted extraction of Undaria pinnatifida was performed using five proteases (Alcalase, Flavourzyme, Neutrase, Trypsin and Protamex) and six carbohydrases (AMG, Dextrozyme, Maltogenase, Promozyme, Viscozyme and Celluclast) in order to acquire extracts rich in antioxidants. Antioxidant activity of the extracts was investigated using electron spin resonance (ESR) spectroscopy on 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide radicals. Extracts exhibited strong radical scavenging activity on DPPH and hydroxyl radical, and activity increased with increasing extract concentration. In contrast to DPPH and hydroxyl radical scavenging activity, extracts showed weak scavenging activity on superoxide radical. Extracts exhibited weak radical scavenging activity compared to vitamin C as a reference compound. However, they are still a good source of antioxidant materials that are safe for consumption and show water-soluble properties. 相似文献
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超声波-酶解法和超声波法提取裙带菜多糖的比较研究 总被引:3,自引:0,他引:3
比较研究超声波-酶解法和超声波法提取裙带菜多糖,并采用Fenton体系研究裙带菜中多糖对羟自由基清除活性作用。选取浸提时间、酶用量、固液比及温度4因素采用L16(45)和L9(34)两个方案分别对超声-酶解提取裙带菜多糖和超声波法提取进行正交试验。得到最佳的提取条件为:超声-酶解提取的裙带菜多糖得率与抗羟自由基优化组合为超声-酶解时间15min、纤维素酶用量2.8×104U/g(酶与藻粉比值)、温度70℃、固液比1:80为最佳条件,在此条件下,裙带菜多糖提取率为(4.522±0.028)%,3.60g/L的裙带菜多糖对羟自由基清除率为(51.70±0.47)%。超声-酶解结合方法提取试验条件对裙带菜多糖提取率影响显著(P<0.01)。试验条件对提取得到的裙带菜多糖羟自由基清除率结果影响不显著(P>0.05)。超声-酶解法的裙带菜多糖提取效果和及其羟自由基清除率能力明显优于超声波法,其结果具有显著性差异(P<0.01)。超声波-酶解结合方法提取裙带菜多糖,提取效率高,多糖清除自由基效果好。 相似文献
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裙带菜属于褐藻门植物,营养价值高,是海洋中的经济褐藻之一。人们食用的部分多为其叶与梗,孢子叶是其繁殖器官,因含较多纤维物质,食用口感较差,在加工过程中常作为废料被丢弃,造成资源浪费。研究发现,孢子叶中含有多种生物活性物质,如多糖、多肽、褐藻多酚、岩藻黄素等,具有抗肿瘤、抗炎、抗氧化、降血脂等生理功效,是功能性食品开发的良好原料。文章绍了裙带菜孢子叶生物活性物质的功能特性及提取方法,并对其在食品中的应用进行了分析和展望,以期为裙带菜孢子叶的综合开发利用提供理论参考。 相似文献
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目的 建立超高效液相色谱法测定山楂原料、提取物和相关食品中金丝桃苷和异槲皮苷的分析方法。方法 采用ACQUITY UPLC BEH C18柱, 以甲酸乙腈-甲酸水为流动相进行梯度洗脱分离金丝桃苷和异槲皮苷, 在紫外检测波长360 nm下进行检测, 外标法定量。结果 金丝桃苷和异槲皮苷的检出限(limit of detections, LODs, S/N=3)均为2 mg/kg, 定量限(limit of quantifications, LOQs, S/N=10)均为5 mg/kg; 在0.5~10.0 mg/L的浓度范围内线性关系良好, 相关系数均为0.999; 在原料、提取物和相关食品中, 金丝桃苷和异槲皮苷的平均回收率分别为83.0%~108.0%和86.2%~105.0%, 相对标准偏差(relative standard deviations, RSDs)分别为1.6%~5.7%和1.1%~3.9%。结论 本方法操作简便、快速、分离度和准确度高, 可用于山楂原料、提取物和相关食品的质量控制。 相似文献
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