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荷叶多糖的提取工艺研究 总被引:2,自引:0,他引:2
荷叶属睡莲科植物,是国家卫生部公布的药食同源物.目前对荷叶的研究多针对其中的黄酮、生物碱等物质,对其中多糖的研究甚少.采用热水浸提法提取荷叶水溶性多糖,选择浸提时间、温度、浸提固液比以及浸提次数作为单因素进行梯度实验,确定其条件范围,再通过进一步的正交实验得到荷叶水溶性多糖浸提工艺的优选因素组合:浸提时间2 h,温度75℃,固液比1∶30,浸提一次. 相似文献
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同步污水处理/发电技术-微生物燃料电池的研究进展 总被引:2,自引:0,他引:2
同步污水处理/发电技术的微生物燃料电池是利用生物催化剂直接把化学能转化为电能,具有能量转化率高、污泥产率低、反应条件温和等优点。本文阐述了微生物燃料电池的工作原理,反应器的类型及结构,综述了其最新的研究进展,并对微生物燃料电池在污水处理领域的发展方向作了展望。 相似文献
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Maria C. Teixeira Nicole S. Lameirinhas Joo P. F. Carvalho Armando J. D. Silvestre Carla Vilela Carmen S. R. Freire 《International journal of molecular sciences》2022,23(12)
Three-dimensional (3D) bioprinting is an innovative technology in the biomedical field, allowing the fabrication of living constructs through an approach of layer-by-layer deposition of cell-laden inks, the so-called bioinks. An ideal bioink should possess proper mechanical, rheological, chemical, and biological characteristics to ensure high cell viability and the production of tissue constructs with dimensional stability and shape fidelity. Among the several types of bioinks, hydrogels are extremely appealing as they have many similarities with the extracellular matrix, providing a highly hydrated environment for cell proliferation and tunability in terms of mechanical and rheological properties. Hydrogels derived from natural polymers, and polysaccharides, in particular, are an excellent platform to mimic the extracellular matrix, given their low cytotoxicity, high hydrophilicity, and diversity of structures. In fact, polysaccharide-based hydrogels are trendy materials for 3D bioprinting since they are abundant and combine adequate physicochemical and biomimetic features for the development of novel bioinks. Thus, this review portrays the most relevant advances in polysaccharide-based hydrogel bioinks for 3D bioprinting, focusing on the last five years, with emphasis on their properties, advantages, and limitations, considering polysaccharide families classified according to their source, namely from seaweed, higher plants, microbial, and animal (particularly crustaceans) origin. 相似文献
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从香辣里脊的原料生产加工工艺成品贮存方式对香辣里脊成品中微生物数量的影响进行了探讨.结果表明:香辣里脊原料的带菌量与成品的带菌量具有相关关系;生产加工工艺中的各参数对成品中微生物数量有很大影响,如蒸煮温度78~80℃,蒸煮时间65min时,成品品质最佳,且能达到商业无菌的要求;成品在冷藏条件下贮存比在常温下贮存效果更佳,且最佳贮存温度为0~7℃. 相似文献
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Zhiling Li Yasushi Inoue Suyin Yang Naoko Yoshida Arata Katayama 《Journal of Bioscience and Bioengineering》2010,110(3):326-332
A mass balance and kinetic investigation of anaerobic dechlorination of pentachlorophenol (PCP) was undertaken using an enriched microbial consortium in a laboratory scale continuous flow column, as a model microbial permeable reactive barrier. The chlorine balance showed that 50 µM PCP was largely dechlorinated to phenol with the formation of a small quantity of 3-chlorophenol as an intermediate metabolite (hydraulic retention time 7.6 days), and the chlorine removal efficiency reached 36 µM d-1. When the initial PCP concentration was increased to 100 µM the chlorine removal efficiency increased 1.5 times. However, the dechlorination activity disappeared after 7.4 pore volumes (58 days), demonstrating the susceptibility of the dechlorination culture to high concentrations of PCP. Lactate released hydrogen as an electron donor during PCP dechlorination, with acetate, propionate, CO2 and CH4 as byproducts. The carbon balance showed that some of the organic carbon source (PCP, lactate) in the influent was converted to gas and utilized for biomass growth in addition to organic metabolites. The kinetic study was conducted in a batch culture and yielded 1.99 mg l-1 biomass growth per unit of chlorine consumption (µM). The Monod equation was well fitted to the specific growth rate of 1.38 d-1 and a half saturation constant of 0.29 µM. The organic chlorine removal rate in the batch culture was consistent with the results in the flow column, indicating the feasibility of and potential for in situ estimation and prediction through batch culture studies. 相似文献