Department of Environmental Microbiology and Biotechnology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87 100 Torun, Poland.
Department of Genetics, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Torun, Gagarina 11, 87 100 Torun, Poland.
Int J Biol Macromol. 2021 Sep 30;187:309-318. doi: 10.1016/j.ijbiomac.2021.07.135. Epub 2021 Jul 24.
The aim of this study was to isolate biofilm-forming bacteria that are capable of degrading polyhydroxybutyrate (PHB) with polyhexamethylene guanidine (PHMG) derivatives. The three types of derivatives incorporated in PHB and their concentration affected the biodegradability of the tested films in both water and compost. The PHMG derivative granular polyethylene wax at the highest concentration significantly inhibited BOD in both environments. At the same time, in water, PHB with PHMG stearate at 1% concentration was also found to inhibit biodegradation but to a lesser extent than PHMG polyethylene wax granulate. Analyzing the values of biofilm abundance and their hydrolytic activity in water, low concentrations of PHMG derivatives (0.2 and 0.6%) slightly inhibited biofilm abundance on the surface of the tested composites. Only granular polyethylene wax PHMG (at 1% concentration) significantly reduced biofilm formation and hydrolase activity in the compost to the greatest extent. Bacteria from biofilm were isolated and identified. Based on the 16S rRNA gene sequence, the strains belong to Bacillus toyonensis HW1 and Variovorax boronicumulans HK3. Introduction of the tested isolates to the environment can enhance composites degradation. However, this requires further research.
本研究旨在分离能够降解聚羟基丁酸酯 (PHB) 的生物膜形成细菌，使用聚六亚甲基胍 (PHMG) 衍生物。三种类型的衍生物与 PHB 结合，其浓度会影响测试薄膜在水和堆肥中的生物降解性。浓度最高的 PHMG 衍生物颗粒状聚乙烯蜡在这两种环境中均显著抑制 BOD。同时，在水中，发现 1%浓度的 PHMG 硬脂酸盐也会抑制生物降解，但程度低于 PHMG 聚乙烯蜡颗粒。在分析水生物膜丰度及其水解活性值时，低浓度的 PHMG 衍生物 (0.2% 和 0.6%) 略微抑制了测试复合材料表面生物膜的丰度。只有 1%浓度的 PHMG 颗粒状聚乙烯蜡最大程度地减少了堆肥中生物膜的形成和水解酶的活性。从生物膜中分离和鉴定了细菌。根据 16S rRNA 基因序列，这些菌株属于藤黄 toyonensis HW1 和 Variovorax boronicumulans HK3。将测试的分离物引入环境可以增强复合材料的降解。然而，这需要进一步的研究。
