Sinisterra-Sierra María Camila, Campos-Valdez Amador, Pereira-Santana Alejandro, Zamora-Briseño Jesús Alejandro, Ramírez-Pérez Sandra L, González-Escobar Jorge L, Kirchmayr Manuel R, Barrera-Martínez Iliana, Robles-Machuca Marcela, Casas-Godoy Leticia
Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, Camino Arenero 1227, El Bajío, 45019, Zapopan, Jalisco, México.
SECIHTI- Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, Unidad Sureste, Parque Científico Tecnológico de Yucatán, 97302, Mérida, Yucatán, México.
Environ Res. 2025 Jun 16;283:122170. doi: 10.1016/j.envres.2025.122170.
Plastic pollution has become an important global environmental concern, emphasizing the urgent need for effective plastic degradation strategies. Microorganisms have demonstrated potential in degrading plastics through enzymatic activities. This study investigated the microbial diversity and enzymatic potential of microorganisms isolated from plastic-contaminated dumpsites located in Mazamitla, Jalisco a west-central region of Mexico. Microbial diversity was assessed through metataxonomic analysis based on 16S rRNA gene sequencing of DNA extracted from soil samples. A total of 946 genera across 49 phyla were identified, with Actinobacteria, Pseudomonadota, Bacillota, Bacteroidota, and Acidobacteria as the most dominant, while at genus level, Pseudomonas, Bacillus, and Streptomyces were the most representative. Culturable microorganisms were isolated, identified, and screened from soil samples for enzymatic activities associated with plastic degradation. From these, 280 mesophilic isolates were recovered, of which 251 were successfully identified. Among them, 94 % belonged to the domain Bacteria, primarily from the phyla Bacillota and Pseudomonadota. The remaining 6 % of isolates were fungi from the phylum Basidiomycota. During agar-based functional enzymatic screening using mineral oil as an inducer, Serratia marcescens demonstrated the highest extracellular carboxylesterase activity (240.3 ± 11.0 U/L), Comamonas testosteroni (193.9 ± 2.5 U/L), and Pseudomonas koreensis (180.4 ± 8.0 U/L) exhibited significant esterase/lipase activities. C. testosteroni (125.6 ± 15.5 U/L), Chryseobacterium joostei (125.1 ± 14.2 U/L), and Bacillus mycoides (120.6 ± 9.9 U/L) were the most active for cutinase activity. Lelliottiaamnigena, S. marcescens, Pseudomonaschlororaphis, and Pseudomonaskilonensis exhibited the highest growth using plastics as the sole carbon source. These results highlight the metabolic diversity and enzymatic capabilities of microorganisms in plastic-contaminated soils, identifying promising candidates for sustainable plastic waste management.
塑料污染已成为一个重要的全球环境问题，凸显了对有效塑料降解策略的迫切需求。微生物已通过酶活性展现出降解塑料的潜力。本研究调查了从位于墨西哥中西部哈利斯科州马萨米特拉的塑料污染垃圾场分离出的微生物的多样性和酶潜力。通过基于从土壤样本中提取的DNA的16S rRNA基因测序的宏分类分析来评估微生物多样性。共鉴定出49个门的946个属，其中放线菌门、假单胞菌门、芽孢杆菌门、拟杆菌门和酸杆菌门最为占主导地位，而在属水平上，假单胞菌属、芽孢杆菌属和链霉菌属最具代表性。从土壤样本中分离、鉴定并筛选可培养微生物的与塑料降解相关的酶活性。从中回收了280株嗜温菌株，其中251株被成功鉴定。其中，94%属于细菌域，主要来自芽孢杆菌门和假单胞菌门。其余6%的分离株是担子菌门的真菌。在以矿物油作为诱导剂的基于琼脂的功能性酶筛选过程中，粘质沙雷氏菌表现出最高的细胞外羧酸酯酶活性（240.3±11.0 U/L），睾丸丛毛单胞菌（193.9±2.5 U/L）和韩国假单胞菌（180.4±8.0 U/L）表现出显著的酯酶/脂肪酶活性。睾丸丛毛单胞菌（125.6±15.5 U/L）、约氏金黄杆菌（125.1±14.2 U/L）和蕈状芽孢杆菌（120.6±9.9 U/L）对角质酶活性最为活跃。水生勒氏菌、粘质沙雷氏菌、绿针假单胞菌和基隆假单胞菌以塑料作为唯一碳源时生长最为旺盛。这些结果突出了塑料污染土壤中微生物的代谢多样性和酶能力，确定了可持续塑料废物管理的有前景的候选菌株。
