Cristina América Morando-Grijalva

(1) Background: Plastic contamination is on the rise, despite ongoing research focused on alternatives such as bioplastics. However, most bioplastics require specific conditions to biodegrade. A promising alternative involves using microorganisms isolated from landfill soils that have demonstrated the ability to degrade plastic materials. (2) Methods: Soil samples were collected, and bacteria were isolated, characterized, and molecularly identified. Their degradative capacity was evaluated using the zone of clearing method, while their qualitative and structural degradative activity was assessed in a liquid medium on poly(butylene succinate) (PBS) films prepared by the cast method. (3) Results: Three strains—Bacillus cereus CHU4R, Acinetobacter baumannii YUCAN, and Pseudomonas otitidis YUC44—were selected. These strains exhibited the ability to cause severe damage to the microscopic surface of the films, attack the ester bonds within the PBS structure, and degrade lower-weight PBS molecules during the process. (4) Conclusions: this study represents the first report of strains isolated in Yucatán with plastic degradation activity. The microorganisms demonstrated the capacity to degrade PBS films by causing surface and structural damage at the molecular level. These findings suggest that the strains could be applied as an alternative in plastic biodegradation.