Abed Raeid M M, Al-Hinai Mahmood, Al-Balushi Yasmin, Haider Lorenz, Muthukrishnan Thirumahal, Rinner Uwe
Biology Department, College of Science, Sultan Qaboos University, P. O. Box: 36, PC 123 Al Khoud, Sultanate of Oman.
Biology Department, College of Science, Sultan Qaboos University, P. O. Box: 36, PC 123 Al Khoud, Sultanate of Oman.
Mar Pollut Bull. 2023 Oct;195:115496. doi: 10.1016/j.marpolbul.2023.115496. Epub 2023 Sep 12.
The Gulf of Oman is becoming increasingly polluted with plastics, hence bioplastics have been considered 'a substitute', although their biodegradability in marine environments has not been well investigated. Most research has been performed on cellulose-based bioplastics, whereas starch-based bioplastics have proven to be a suitable, but less researched, alternative. This study is the first of its kind designed to investigate the degradability of two different types of starch-based bioplastic bags, available in the market and labeled as "biodegradable", in the pelagic and benthic zones of one of the warmest marine environment in the world. Fourier-Transform Infrared Spectroscopy (FTIR) showed a clear reduction in the presence of OH, CH, and CO in the bioplastic bags after 5 weeks of immersion. Thermo-Gravimetric Analysis (TGA) indicated degradation of glycerol, starch, and polyethylene. The biofouling bacterial communities on bioplastic surfaces showed distinct grouping based on the immersion zone. Candidaatus saccharibacteria, Verrucomicrobiae, Acidimicrobiia and Planctomycetia sequences were only detectable on bioplastics in the pelagic zone, whereas Actinomyces, Pseudomonas, Sphingobium and Acinetobacter related sequences were only found on bioplastics in the benthic layer. We conclude that starch-based bioplastics are more readily degradable in the Gulf of Oman than conventional plastics, hence could serve as a better environmentally friendly alternative.
阿曼湾正日益受到塑料污染，因此生物塑料被视为“一种替代品”，尽管其在海洋环境中的生物降解性尚未得到充分研究。大多数研究针对的是纤维素基生物塑料，而淀粉基生物塑料已被证明是一种合适但研究较少的替代品。本研究首次旨在调查市场上两种不同类型、标有“可生物降解”的淀粉基生物塑料袋在世界最温暖海洋环境之一的远洋和底栖区域的降解性。傅里叶变换红外光谱（FTIR）显示，浸泡5周后，生物塑料袋中OH、CH和CO的含量明显降低。热重分析（TGA）表明甘油、淀粉和聚乙烯发生了降解。生物塑料表面的生物污垢细菌群落根据浸泡区域呈现出明显的分组。仅在远洋区域的生物塑料上可检测到“Candidatus saccharibacteria”、疣微菌门、酸微菌纲和浮霉菌门的序列，而仅在底层生物塑料上发现了放线菌、假单胞菌、鞘氨醇单胞菌和不动杆菌相关序列。我们得出结论，淀粉基生物塑料在阿曼湾比传统塑料更容易降解，因此可以作为更好的环保替代品。
