Biodegradable plastic composites were produced from mixtures of polyvinyl alcohol (PVA) and starch, which were mixed with different natural fillers [sugarcane bagasse (SB), oat hulls (OH) or silkworm exuvia (SE)] and nutrients to stimulate the biodegrading microbiota. The physicochemical and biodegradability characteristics of the produced materials were studied, in addition to their influence over the microbiota involved in biodegradation. The SB-composite showed reduced solubility in water, a lower water absorption capacity and a slower mineralization rate when buried in a commercial substrate for seedlings production, as compared with those of the OH- and SE-composites. Scanning electron micrographs demonstrated the increased colonization of materials by the biodegrading microbiota over time, which were predominated by filamentous fungi in OH- and SE-composites, while the SB-composite was predominantly colonized by bacteria. A Fourier transform-infrared spectroscopy (FT-IR) analysis of the biodegraded materials highlighted the chemical differences in the protein and carbohydrate content between formulations, corroborating the activity of different microbial groups on their mineralization. Regardless of its composition, the mineralization rate of the materials was positively correlated with the microbial biomass carbon (C mic) and basal respiration (R_B) of the substrate. However, the correlation between the mineralization rate and the metabolic quotient of the substrate (qCO₂) was negative for the OH- and SE-composites, while the SB-composite showed no significant correlation among these variables. The differences observed in the formulations indicated that biodegradable plastics can be designed for a given goal by selecting the most appropriate formulation.

由聚乙烯醇（PVA）和淀粉的混合物生产可生物降解的塑料复合材料，将其与不同的天然填料[蔗糖蔗渣（SB），燕麦壳（OH）或蚕ex（SE）]和营养物质混合以刺激生物降解菌群。除了对参与生物降解的微生物群的影响外，还研究了所生产材料的物理化学和生物降解特性。与OH-和SE-复合材料相比，当将SB-复合材料埋在用于生产苗木的商业基质中时，其在水中的溶解度降低，吸水能力降低，矿化速率降低。扫描电子显微镜照片显示，随着时间的推移，生物降解的微生物群会增加材料的定殖，它们在OH和SE复合材料中以丝状真菌为主，而SB复合材料则主要被细菌定植。对生物降解材料的傅立叶变换红外光谱（FT-IR）分析突出显示了制剂之间蛋白质和碳水化合物含量的化学差异，从而证实了不同微生物在矿化过程中的活性。无论其组成如何，材料的矿化率与微生物生物量碳（C mic）和基础呼吸（R 证实了不同微生物群在矿化过程中的活性。无论其成分如何，材料的矿化率与微生物生物量碳（C mic）和基础呼吸（R 证实了不同微生物群在矿化过程中的活性。无论其成分如何，材料的矿化率与微生物生物量碳（C mic）和基础呼吸（R_B）的基材。然而，矿化速率与底物的代谢商（qCO ₂）之间的相关性对于OH和SE复合物是负的，而SB复合物在这些变量之间没有显着的相关性。在配方中观察到的差异表明，通过选择最合适的配方，可以针对给定的目标设计可生物降解的塑料。