INRS-ETE, Université du Québec, 490 rue de la Courrone, Québec, Canada G1K 9A9.
Bioresour Technol. 2012 Nov;123:303-11. doi: 10.1016/j.biortech.2012.07.110. Epub 2012 Aug 7.
Mathematic relationships between spore concentrations, delta-endotoxin concentrations and entomotoxicity (Tx) of Bacillus thuringiensis var. kurstaki HD-1 (Btk HD-1) preparations produced in six different media were analysed. The relationship between delta-endotoxin and spore concentration and SpTx-spore (specific Tx per 1000 spore) and spore concentration produced in the different media (starch industry wastewater (SIW) with total solids (TS) concentration of 15g/L, SIW with TS of 30g/L, SIW supplemented with 0.2% (w/v) colloidal chitin, SIW supplemented with 1.25% (w/v) cornstarch and 0.2% (v/v) Tween 80, secondary sludge, and semi-synthetic medium) strictly followed the Power law. Tx and delta endotoxin concentration followed the exponential relation whereas a definite relation between Tx and spore concentration could not be established. Spore and delta-endotoxin produced at the early time (12h) during fermentation might be more toxic than those produced during latter period of fermentation irrespective of media used. Tx and delta-endotoxin concentration exhibited a semi-log linear relationship. Based on these findings, delta-endotoxin concentration can be determined rapidly to monitor the progress of the biopesticide production process.
分析了在六种不同培养基中生产的苏云金芽孢杆菌 var. kurstaki HD-1（Btk HD-1）制剂的孢子浓度、δ-内毒素浓度和杀虫毒力（Tx）之间的数学关系。δ-内毒素与孢子浓度的关系以及 SpTx-孢子（每 1000 个孢子的特定 Tx）和在不同培养基中产生的孢子浓度（总固体（TS）浓度为 15g/L 的淀粉工业废水（SIW）、TS 为 30g/L 的 SIW、添加 0.2%（w/v）胶体几丁质的 SIW、添加 1.25%（w/v）玉米淀粉和 0.2%（v/v）吐温 80 的 SIW、二级污泥和半合成培养基）严格遵循幂律。Tx 和 δ-内毒素浓度遵循指数关系，而 Tx 和孢子浓度之间则不能建立明确的关系。在发酵的早期（12 小时）产生的孢子和 δ-内毒素可能比在发酵后期产生的更具毒性，无论使用哪种培养基。Tx 和 δ-内毒素浓度表现出半对数线性关系。基于这些发现，可以快速测定 δ-内毒素浓度来监测生物农药生产过程的进展。
