Sidari Rossana, Pittarello Marco, Rodinò Maria Teresa, Panuccio Maria Rosaria, Lo Verde Gabriella, Laudicina Vito Armando, Gelsomino Antonio
Department of Agraria, Mediterranea University of Reggio Calabria, Reggio Calabria, Italy.
Department of Agricultural, Food and Forestry Science, University of Palermo, Palermo, Italy.
Front Microbiol. 2025 Jul 9;16:1597786. doi: 10.3389/fmicb.2025.1597786. eCollection 2025.
Mulching is a common agricultural practice owing to its advantages during cultivation. To reduce plastic residues in soil, the use of biodegradable films instead of plastic is desirable. Once buried in soil, biodegradable films undergo degradation driven by abiotic and biotic factors such as the activity of soil microbes. The aim of this study was to select microbial strains whose enzymatic activities can accelerate the degradation of innovative, biodegradable, cellulose-chitosan-based films.
To this end, 119 bacteria were isolated from compost, digestate, agricultural soil, and the gut or casts of earthworms and subsequently tested for their ability to break down two types of biodegradable films, which were enriched with nitrogen and phosphorus (+NP) and the unenriched control (-NP).
The ability of the bacteria to accelerate the degradation of the films was strain dependent, and the degradation proceeded at different speeds and degrees. Of the 119 isolated bacteria, 46 strains were able to degrade the unenriched (-NP) film to a greater or lesser extent, with 20 of them able to break it down completely. With regard to the enriched (+NP) film, 10 strains were able to degrade it, with six strains being able to break it down completely. These figures include eight strains that were able to degrade both the enriched and unenriched films. Four novel cellulose-chitosan-degrading bacteria were selected and identified as ACT-8, spp. DL-A1-11, spp. I1, and F7. These strains will be further studied to assess their activity in a mesocosm-scale trial. The novelty of this study is the identification of bacterial strains capable of degrading cellulose-chitosan-based films. This finding contributes to the common effort to reduce the presence of axenic residues in the environment and may have a positive impact on the sector, considering the possibility of applying these strains in bioaugmentation.
由于覆盖在耕作过程中的优势，它是一种常见的农业实践。为了减少土壤中的塑料残留，使用可生物降解薄膜而非塑料是理想的选择。一旦埋入土壤，可生物降解薄膜会在非生物和生物因素（如土壤微生物活动）的驱动下发生降解。本研究的目的是筛选出酶活性能够加速新型可生物降解的纤维素 - 壳聚糖基薄膜降解的微生物菌株。
为此，从堆肥、沼渣、农业土壤以及蚯蚓的肠道或粪便中分离出119株细菌，随后测试它们分解两种可生物降解薄膜的能力，这两种薄膜分别是富含氮和磷的（+NP）以及未富集的对照薄膜（-NP）。
细菌加速薄膜降解的能力因菌株而异，降解以不同的速度和程度进行。在分离出的119株细菌中，46株能够不同程度地降解未富集的（-NP）薄膜，其中20株能够将其完全分解。对于富集的（+NP）薄膜，10株能够降解它，其中6株能够将其完全分解。这些数据包括8株能够同时降解富集和未富集薄膜的菌株。挑选并鉴定出4株新型纤维素 - 壳聚糖降解细菌，分别为ACT - 8、spp. DL - A1 - 11、spp. I1和F7。这些菌株将在中尺度试验中进一步研究以评估其活性。本研究的新颖之处在于鉴定出了能够降解纤维素 - 壳聚糖基薄膜的细菌菌株。这一发现有助于共同努力减少环境中无菌残留物的存在，并且考虑到将这些菌株应用于生物强化的可能性，可能会对该领域产生积极影响。
