Instituto Tecnológico Superior de Tierra Blanca, Av. Veracruz S/N Esq. Héroes de Puebla, Colonia Pemex., C.P. 95180, Tierra Blanca, Veracruz, Mexico.
Universidad de Guanajuato, Lascuráin de Retana No. 5, Colonia Centro, C.P. 36000, Guanajuato, Gto., Mexico.
Environ Sci Pollut Res Int. 2020 Jun;27(18):23035-23047. doi: 10.1007/s11356-020-08831-z. Epub 2020 Apr 24.
Plastic and hydrocarbon pollution in aquatic ecosystems is a worldwide reality and serious concern today. Plastic debris presents a threat to ecosystems and organisms. Hydrocarbons are also considered priority pollutants. The hydrophobicity of the polymer in combination with the high surface area causes plastics to act as a vector for organic contaminants such as hydrocarbons. The first aim of this work was to evaluate the presence of plastic and hydrocarbon pollution in water from two reefs and two rivers and to identify plastic in six sediment beaches in Veracruz State, Mexico. In addition, the second aim was to analyse the ability of a bacterial consortium to biodegrade hydrocarbons in an airlift bioreactor and to identify degrading bacterial strains of polyethylene terephthalate (PET). Microplastics (100 nm-5 mm) were found in four water samples. Fragments of plastic collected from the reefs ranged in size from 0.716 to 32 μm and in rivers from 0.833 to 784 μm. On the sediment beaches, macroplastics of sizes 2-10 cm were detected. A number of hydrocarbons were also detected in the water samples of both reefs and one river, including n-octane, n-nonane, phenanthrene, n-eicosane, n-dotriacontane, n-hexatriacontane, n-triacontane, and n-tetratriacontane. As a biotechnological alternative for remediation of hydrocarbons and plastics, we attempted to produce a collection of native microorganisms able to degrade them. This work shows results from the bioprospection of a bacterial consortium (Xanthomonas, Acinetobacter bouvetii, Shewanella, and Aquamicrobium lusatiense) for hydrocarbon biodegradation in an airlift bioreactor. The tested consortium was able to successfully degrade the maximum diesel concentration (20 g L) tested for 10 days. Also, the first visual evidence of PET degradation by an isolated forest-native bacterial strain showed that Bacillus muralis is the most efficient degrader.
水生生态系统中的塑料和碳氢化合物污染是当今全球性的现实问题和严重关切。塑料碎片对生态系统和生物构成威胁。碳氢化合物也被认为是优先污染物。聚合物的疏水性和高表面积结合在一起，使塑料成为有机污染物（如碳氢化合物）的载体。这项工作的首要目标是评估来自两个珊瑚礁和两条河流的水中的塑料和碳氢化合物污染情况，并确定墨西哥韦拉克鲁斯州六个沉积物海滩上的塑料。此外，第二个目标是分析细菌混合物在气升式生物反应器中降解碳氢化合物的能力，并鉴定聚对苯二甲酸乙二醇酯（PET）的降解细菌菌株。在四个水样中发现了微塑料（100nm-5mm）。从珊瑚礁收集的塑料碎片大小范围为 0.716 至 32μm，从河流中收集的大小范围为 0.833 至 784μm。在沉积物海滩上，检测到大小为 2-10cm 的大塑料。在两个珊瑚礁和一条河流的水样中还检测到一些碳氢化合物，包括正辛烷、正壬烷、菲、正二十烷、正三十二烷、正二十六烷、正三十烷和正四十四烷。作为碳氢化合物和塑料修复的生物技术替代方法，我们尝试生产能够降解它们的天然微生物混合物。这项工作展示了在气升式生物反应器中进行碳氢化合物生物降解的细菌混合物（黄单胞菌、鲍氏不动杆菌、希瓦氏菌和水微菌）的生物勘探结果。测试的混合物能够成功地在 10 天内降解测试的最大柴油浓度（20g/L）。此外，分离的森林本土细菌菌株对 PET 降解的初步观察证据表明，枯草芽孢杆菌是最有效的降解菌。
