Humbert Pascal, Vemmer Marina, Giampà Marco, Bednarz Hanna, Niehaus Karsten, Patel Anant V
Faculty of Engineering and Mathematics, Fermentation and Formulation of Biologicals and Chemicals, Bielefeld University of Applied Sciences, Interaktion 1, 33619, Bielefeld, Germany.
Faculty of Biology, Center for Biotechnology (CeBiTec), Proteome and Metabolome Research, Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany.
World J Microbiol Biotechnol. 2017 Apr;33(4):71. doi: 10.1007/s11274-017-2237-2. Epub 2017 Mar 13.
CO is known as a major attractant for many arthropod pests which can be exploited for pest control within novel attract-and-kill strategies. This study reports on the development of a slow-release system for CO based on calcium alginate beads containing granular corn starch, amyloglucosidase and Saccharomyces cerevisiae. Our aim was to evaluate the conditions which influence the CO release and to clarify the biochemical reactions taking place within the beads. The amyloglucosidase was immobilized with a high encapsulation efficiency of 87% in Ca-alginate beads supplemented with corn starch and S. cerevisiae biomass. The CO release from the beads was shown to be significantly affected by the concentration of amyloglucosidase and corn starch within the beads as well as by the incubation temperature. Beads prepared with 0.1 amyloglucosidase units/g matrix solution led to a long-lasting CO emission at temperatures between 6 and 25 °C. Starch degradation data correlated well with the CO release from beads during incubation and scanning electron microscopy micrographs visualized the degradation of corn starch granules by the co-encapsulated amyloglucosidase. By implementing MALDI-ToF mass spectrometry imaging for the analysis of Ca-alginate beads, we verified that the encapsulated amyloglucosidase converts starch into glucose which is immediately consumed by S. cerevisiae cells. When applied into the soil, the beads increased the CO concentration in soil significantly. Finally, we demonstrated that dried beads showed a CO production in soil comparable to the moist beads. The long-lasting CO-releasing beads will pave the way towards novel attract-and-kill strategies in pest control.
一氧化碳是许多节肢动物害虫的主要引诱剂，可用于新型诱捕杀灭策略中的害虫防治。本研究报道了一种基于含有颗粒状玉米淀粉、淀粉葡萄糖苷酶和酿酒酵母的海藻酸钙珠的一氧化碳缓释系统的开发。我们的目的是评估影响一氧化碳释放的条件，并阐明珠粒内部发生的生化反应。淀粉葡萄糖苷酶以87%的高包封效率固定在补充有玉米淀粉和酿酒酵母生物质的海藻酸钙珠中。结果表明，珠粒中淀粉葡萄糖苷酶和玉米淀粉的浓度以及孵育温度对珠粒中一氧化碳的释放有显著影响。用0.1淀粉葡萄糖苷酶单位/克基质溶液制备的珠粒在6至25°C的温度下会产生持久的一氧化碳排放。淀粉降解数据与孵育过程中珠粒的一氧化碳释放密切相关，扫描电子显微镜图像显示了共包封的淀粉葡萄糖苷酶对玉米淀粉颗粒的降解。通过实施基质辅助激光解吸电离飞行时间质谱成像分析海藻酸钙珠，我们证实包封的淀粉葡萄糖苷酶将淀粉转化为葡萄糖，而葡萄糖立即被酿酒酵母细胞消耗。当应用于土壤中时，珠粒显著提高了土壤中的一氧化碳浓度。最后，我们证明干燥的珠粒在土壤中产生的一氧化碳与潮湿的珠粒相当。这种持久释放一氧化碳的珠粒将为害虫防治中的新型诱捕杀灭策略铺平道路。
