Quantitative assessment of extraction methods for bound extracellular polymeric substances (B-EPSs) produced by Microcystis sp. and Scenedesmus sp.
Quantitative assessment of extraction methods for bound extracellular polymeric substances (B-EPSs) produced by Microcystis sp. and Scenedesmus sp.
复制标题
微囊藻产生的结合胞外聚合物 (B-EPS) 提取方法的定量评估。
DOI：
10.1016/j.algal.2021.102289
复制
发表时间：
2021-04-21
影响因子：
5.1
通讯作者：
Huangfu, Xiaoliu
中科院分区：
文献类型：
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作者：
Huang, Ruixing;He, Qiang;Huangfu, Xiaoliu
胞外聚合物（EPS）在微生物的生长和存活中起着重要作用。由于它们的物理化学特性（例如，多糖和蛋白质含量高，具有抗病毒、抗肿瘤和抗氧化的作用。然而，缺乏标准的评价方法，有效的提取限制了进一步的研究，EPS的特性或功能及其商业应用。在本研究中，开发了结合EPS（B-EPS）提取效率评估模型（B-E-4模型）以评估两种微藻（即，原核微囊藻属和真核栅藻属），包括加热、离心、超声、乙二胺四乙酸、阳离子交换树脂或氢氧化钠。引入评价参数k来表示B-EPS的提取产率，将其归一化为每单位质量释放的细胞内有机物。该研究表明，在70 ℃下加热10分钟导致微囊藻和栅藻的最高提取效率，k值分别为12.34 +/-1.48和6.02 +/-0.14。此外，细胞破裂的模型预测与本研究和文献中获得的流式细胞术分析结果非常一致。此外，为了验证本研究建立的B-E-4模型的适用性，利用该模型对前期研究中采用的各种方法提取微藻粘膜新囊藻SX的效果进行了评价，发现阳离子交换树脂处理6 h是最佳方法。本研究建立的B-E-4模型是优化微藻B-EPS提取工艺的有力工具。
Extracellular polymeric substances (EPSs) play a significant role in the growth and survival of microorganisms. They have been applied in various fields, such as animal feed, pharmaceuticals and cosmetics, due to their physicochemical characteristics (e.g., high contents of polysaccharides and proteins, properties of antivirus, antitumor and antioxidant). However, lack of standard evaluation methods for efficient extraction restricts further investigation on the characteristics or functions of EPSs and their commercial applications. In this study, the Bound-EPS (B-EPS) Extraction Efficiency Evaluation Model (B-E-4 Model) was developed to assess various extraction methods for two microalgae (i.e., the prokaryotic Microcystis sp. and the eukaryotic Scenedesmus sp.), including heating, centrifugation, ultrasound, ethylenediaminetetraacetic acid, cation-exchange resin or sodium hydroxide. The evaluation parameter k, was introduced to represent the extraction yields of B-EPSs, which was normalized to the per unit mass of released intracellular organics. This study revealed that heating at 70 degrees C for 10 min led to the highest extraction efficiency for both Microcystis sp. and Scenedesmus sp., with k values of 12.34 +/- 1.48 and 6.02 +/- 0.14, respectively. Moreover, model predictions for cell rupture were in close agreement with the results of flow cytometry analysis obtained in this study and the literature. Moreover, to test the applicability of B-E-4 Model established in this study, it was utilized to evaluate the extraction efficiencies of various methods applied in a previous study on the microalgae Neocystis mucosa SX, and cation-exchange resin treating for 6 h was found to be the optimal method. The B-E-4 model developed in this study was proven to be a powerful tool for optimizing the microalgal B-EPS extraction procedures.