Since the use of biodegradable polymers for food packaging is becoming popular, it is important to investigate the biodegradable-polymer-hydrolyzing potential of microorganisms in fermented foods. Here, we focused on 4 Japanese washed-rind cheeses. Metagenomic analyses revealed that microbiota in the 4 Japanese washed-rind cheeses was composed of bacteria classified into 515 operational taxonomic units (OTUs) and fungi classified into 74 OTUs. Remarkably, a considerable number of marine bacteria were identified in 3 of 4 cheeses. Further, we isolated a poly(3-hydroxybutyrate) (P(3HB))-degrading bacterium, designated as strain MC1, from one of the cheeses—Muchuri. The strain was a gram-negative, rod-shaped bacterium. It grew well and formed a large clear zone on P(3HB)-containing medium at a temperature range of 30–37 °C, while it did not degrade P(3HB) at 4 °C. The phenotypic properties and phylogenetic inference indicated that strain MC1 is related to Alcanivorax dieselolei B-5^T, which is a marine inhabitant. Our study demonstrated that MC1 degrades P(3HB) and that components in cheese promote the degradation of P(3HB) while nutrient-rich conditions suppress it. This suggests that packaging material made of P(3HB) for cheeses could be used under low temperatures and nutrient-rich conditions.

由于在食品包装中使用可生物降解的聚合物变得很普遍，因此研究发酵食品中微生物的可生物降解的聚合物水解潜力非常重要。在这里，我们重点研究了4种日本水洗奶酪。元基因组学分析表明，在4种日本水洗干酪中，微生物群是由细菌分类为515个操作生物分类单位（OTU），而真菌则分类为74个OTU。值得注意的是，在4种奶酪中的3种中发现了相当数量的海洋细菌。此外，我们从一种奶酪-Muchuri中分离了降解聚（3-羟基丁酸酯）（P（3HB））的细菌，命名为MC1菌株。该菌株是革兰氏阴性杆状细菌。在30-37°C的温度范围内，它生长良好并在含P（3HB）的培养基上形成了一个较大的净区，而在4°C时它不会降解P（3HB）。表型特性和系统发育推断表明，菌株MC1与Alcanivorax dieselolei B-5 ^T，是一种海洋生物。我们的研究表明，MC1可降解P（3HB），而奶酪中的成分可促进P（3HB）的降解，而营养丰富的条件会抑制P（3HB）。这表明由P（3HB）制成的用于奶酪的包装材料可在低温和营养丰富的条件下使用。