Polyhydroxyalkanoates (PHAs) are bioplastic substitutes for petroleum-derived plastics that may help to reduce the increasing environmental impact of plastic pollution. Among them, polyhydroxybutyrate (PHB) is a promising biopolymer, incentivizing many researchers to search for PHB-producing and PHB-degrading bacteria for improved PHB utilization. Many novel PHB-producing microorganisms have been discovered; however, relatively few PHB-degrading bacteria have been identified. Six PHB-degrading bacteria were found in marine soil and investigated their PHB-degrading abilities under various temperature and salinity conditions using solid-media based culture. Finally, thermotolerant and halotolerant PHB-degrader Bacillus sp. JY14 was selected. PHB degradation was confirmed by monitoring changes in the physical and chemical properties of PHB films incubated with Bacillus sp. JY14 using scanning electron microscopy, Fourier-transform infrared spectroscopy, and gel permeation chromatography. Further, PHB degradation ability of Bacillus sp. JY14 was measured in liquid culture by gas chromatography. After 14 days of cultivation with PHB film, Bacillus sp. JY14 achieved approximately 98% PHB degradation. Applying various bioplastics to assess the bacteria's biodegradation capabilities, the result showed that Bacillus sp. JY14 could also degrade P(3HB-co-4HB) and P(3HB-co-3HV). Overall, this study identified a thermotolerant and halotolerant bacteria capable of PHB degradation under solid and liquid conditions. These results suggest that this bacteria could be utilized to degrade various PHAs.

聚羟基链烷酸酯 (PHA) 是石油衍生塑料的生物塑料替代品，可能有助于减少塑料污染对环境的日益增加的影响。其中，聚羟基丁酸 (PHB) 是一种很有前途的生物聚合物，激励许多研究人员寻找产生 PHB 和降解 PHB 的细菌，以提高 PHB 的利用率。已经发现了许多新的产PHB微生物；然而，已鉴定出相对较少的 PHB 降解细菌。在海洋土壤中发现了六种降解 PHB 的细菌，并使用基于固体培养基的培养研究了它们在各种温度和盐度条件下的 PHB 降解能力。最后，耐热和耐盐的 PHB 降解芽孢杆菌sp. 选择了JY14。通过监测与芽孢杆菌培养的 PHB 薄膜的物理和化学性质的变化来确认 PHB 降解。JY14 使用扫描电子显微镜、傅里叶变换红外光谱和凝胶渗透色谱法。此外，芽孢杆菌属的PHB 降解能力。JY14 在液体培养中通过气相色谱法测定。用 PHB 膜培养 14 天后，芽孢杆菌属。JY14 实现了大约 98% 的 PHB 降解。应用各种生物塑料来评估细菌的生物降解能力，结果表明芽孢杆菌属。JY14 还可以降解 P(3HB- co -4HB) 和 P(3HB- co-3HV）。总的来说，这项研究确定了一种能够在固体和液体条件下降解 PHB 的耐热和耐盐细菌。这些结果表明，这种细菌可用于降解各种 PHA。