Department of Genetics, Faculty of Biology and Veterinary Science, Nicolaus Copernicus University in Toruń, Gagarina 11, 87-100 Torun, Poland.
Department of Environmental Microbiology and Biotechnology, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University in Toruń, Gagarina 11, 87-100 Torun, Poland.
Int J Biol Macromol. 2023 Jun 1;239:124226. doi: 10.1016/j.ijbiomac.2023.124226. Epub 2023 Mar 28.
The plasticized film was made of polylactide and birch tar, which was used in a concentration of 1, 5 and 10 % by weight. Tar was added to the polymer to obtain materials with antimicrobial properties. The main purpose of this work is to characterize and biodegradation of this film after the end of its use. Therefore, the following analyzes were performed: enzymatic activity of microorganisms in the presence of polylactide (PLA) film containing birch tar (BT), biodegradation process in compost, barrier changes and structural properties of the film before and after biodegradation and bioaugmentation. Biological oxygen demand BOD21, water vapor permeability (Pv), oxygen permeability (Po), scanning electron microscopy (SEM) and enzymatic activity of microorganisms were assessed. Microorganism strains Bacillus toyonensis AK2 and Bacillus albus AK3 were isolated and identified, which constituted an effective consortium increasing the susceptibility of polylactide polymer material with tar to biodegradation in compost. Analyses with the use of the above-mentioned strains had an impact on the change of physicochemical properties, e.g. the presence of biofilm on the surface of the analyzed films and the reduction of the barrier properties of the film, which translates into the recorded susceptibility to biodegradation of these materials. The analyzed films can be used in the packaging industry, and after use, subjected to intentional biodegradation processes, including bioaugmentation.
该增塑薄膜由聚乳酸和桦木焦油制成，其浓度分别为 1%、5%和 10%（按重量计）。向聚合物中添加焦油是为了获得具有抗菌性能的材料。这项工作的主要目的是对该薄膜使用结束后的特性和生物降解进行表征。因此，进行了以下分析：在含有桦木焦油（BT）的聚乳酸（PLA）薄膜存在的情况下微生物的酶活性、在堆肥中的生物降解过程、阻隔变化以及生物降解前后薄膜的结构特性和生物增强。评估了生物需氧量 BOD21、水蒸气透过率（Pv）、氧气透过率（Po）、扫描电子显微镜（SEM）和微生物的酶活性。分离并鉴定了枯草芽孢杆菌 AK2 和白地霉 AK3 两种菌株，它们构成了一个有效的联合体，增加了含有焦油的聚乳酸聚合物材料在堆肥中生物降解的敏感性。使用上述菌株进行的分析对物理化学性质的变化产生了影响，例如分析薄膜表面上生物膜的存在以及薄膜阻隔性能的降低，这转化为记录的这些材料的生物降解敏感性。分析用的薄膜可用于包装行业，使用后可进行有意的生物降解过程，包括生物增强。
