Briega Iván, Garde Sonia, Sánchez Carmen, Rodríguez-Mínguez Eva, Picon Antonia, Ávila Marta
Departamento de Tecnología de Alimentos, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), CSIC, Carretera de La Coruña km 7, 28040 Madrid, Spain.
Foods. 2025 Mar 22;14(7):1105. doi: 10.3390/foods14071105.
Dairy-borne spp., known for causing spoilage, may also exhibit antibiotic resistance and form biofilms, enhancing their persistence in dairy environments and contaminating final products. This study examined biofilm formation and antibiotic resistance in 106 spp. strains isolated from milk, whey, and spoiled dairy products. Phylogenetic analysis (based on partial sequences) grouped most strains within the group, clustering into the , , , and subgroups. Biofilm formation in polystyrene microplates was assessed at 6 °C and 25 °C by crystal violet staining. After 48 h, 72% and 65% of strains formed biofilms at 6 °C and 25 °C, respectively, with higher biomass production at 6 °C. High biofilm producers included most , , , , , and strains. The gene, associated with biofilm formation, was detected in 60% of the biofilm producers, but was absent in , , , and . Antibiotic susceptibility was tested using the disk diffusion method. All strains were susceptible to amikacin and tobramycin; however, 73% of the strains were resistant to aztreonam, 28% to imipenem and doripenem, 19% to ceftazidime, 13% to meropenem, and 7% to cefepime. A multiple antibiotic resistance index (MARI) > 0.2 was found in 30% of the strains, including multidrug-resistant ( = 15) and extensively drug-resistant ( = 3) strains. These findings highlight spp. as persistent contaminants and antibiotic resistance reservoirs in dairy environments and products, posing public health risks and economic implications for the dairy industry.
源自乳制品的某些菌种，以引起腐败而闻名，它们还可能表现出抗生素抗性并形成生物膜，从而增强其在乳制品环境中的持久性并污染最终产品。本研究检测了从牛奶、乳清和变质乳制品中分离出的106株该类菌种的生物膜形成情况和抗生素抗性。系统发育分析（基于部分序列）将大多数菌株归入该菌群，聚为、、、和亚群。通过结晶紫染色在6℃和25℃下评估聚苯乙烯微孔板中的生物膜形成情况。48小时后，分别有72%和65%的该类菌株在6℃和25℃下形成生物膜，在6℃下生物量产量更高。高生物膜产生菌包括大多数、、、、、和菌株。在60%的生物膜产生菌中检测到与生物膜形成相关的基因，但在、、、和中未检测到。使用纸片扩散法测试抗生素敏感性。所有菌株对阿米卡星和妥布霉素敏感；然而，73%的菌株对氨曲南耐药，28%对亚胺培南和美罗培南耐药，19%对头孢他啶耐药，13%对美罗培南耐药，7%对头孢吡肟耐药。在30%的菌株中发现多重抗生素抗性指数（MARI）>0.2，包括多重耐药（=15）和广泛耐药（=3）菌株。这些发现突出了该类菌种作为乳制品环境和产品中持久性污染物及抗生素抗性储存库的特点，对乳制品行业构成公共卫生风险和经济影响。
