温度如何影响混合微生物培养中的多基酸盐的生物合成
Tania Palmeiro-Sánchez1, Alison Graham1, Piet Lens1
1Department of Microbiology, College of Science and Engineering and Ryan Institute, University of Galway, Galway, Ireland.
概括
介质性温度 (30°C) 在活性污泥中产生了最高的聚3-基酸-co-3-基酸 (PHBV) 积累. 较高的温度增加了PHBV的分子量,但有利于xybutyrate而不是xyvalerate生产.
科学领域:
- 微生物生物技术 微生物生物技术
- 聚合物科学 聚合物科学
- 环境工程 环境工程
背景情况:
- 聚基酸 (PHAs),包括聚3-基酸-co-3-基酸 (PHBV),是微生物产生的可生物降解聚合物.
- 优化PHA生产需要了解环境因素 (如温度) 对微生物群落的影响.
- 活性污泥是PHA积累微生物联合体的常见来源.
研究的目的:
- 研究不同操作温度 (心理友好性,中性友好性,热友好性) 对微生物群体PHA积累和产生的影响.
- 为了描述在不同温度下生产的PHBV共聚物.
- 在测试条件下确定PHBV积累的最佳温度.
主要方法:
- 三个连续的批量反应堆并行运行,使用活性污泥.
- 反应器保持在不同的温度:15°C (精神性),30°C (介质性) 和48°C (热性).
- 操作参数 (OLR,HRT,SRT,周期长度,C/N比率) 在反应堆中保持不变,温度是唯一的变量.
主要成果:
- 中性恋群体 (30°C) 的PHBV积累率最高 (40.3 ± 7.0 wt%),明显超过心理 (17.7 ± 5.7 wt%) 和热性恋群体 (14.8 ± 0.3 wt%).
- 在30°C (0.64 ± 0.05 CmmolPHBV /CmmolVFA) 时,PHBV生产产量最高,而在15°C (0.41 ± 0.12) 和48°C (0.39 ± 0.14) 时则最高.
- 较高的操作温度与PHBV分子量增加以及合聚合物中xybutyrate (HB) 与xyvalerate (HV) 的比例较大相关.
结论:
- 操作温度显著影响PHBV积累效率和活性污泥中的共聚合物组成.
- 在研究的运行参数下,中性环境 (30°C) 是最大限度地提高PHBV积累和生产产量的最佳条件.
- 温度影响PHBV的物理化学特性,特别是随着温度的上升而增加分子量.
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