Departamento de Veterinária, InsPOA- Laboratório de Inspeção de Produtos de Origem Animal, Universidade Federal de Viçosa, Viçosa, 36570 900, MG, Brazil.
InovaLeite - Laboratório de Pesquisa em Leites e Derivados, Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa, Viçosa, 36570 900, MG, Brazil.
Braz J Microbiol. 2024 Sep;55(3):2539-2545. doi: 10.1007/s42770-024-01391-1. Epub 2024 May 24.
Pediococcus pentosaceus ST65ACC is a bacteriocinogenic lactic acid bacteria (LAB) isolated from Brazilian artisanal cheese that is capable of inhibiting different food pathogens, mainly Listeria monocytogenes. The production of bacteriocins can be influenced by several growth conditions, such as temperature, pH, and medium composition. This study aimed to evaluate the effect of different culture media on the production of bacteriocins and antimicrobial activity of P. pentosaceus ST65ACC on L. monocytogenes Scott A. The strains were inoculated alone and in coculture in four different media: BHI broth, MRS broth, meat broth, and reconstituted skim milk (RSM) 10% (w/v). The culture media were then incubated at 37 °C for 96 h, and count analysis, pH measurement, and bacteriocin production were performed at 0, 24, 48, 72 and 96 h. L. monocytogenes was inhibited to nondetectable levels in coculture with P. pentosaceus ST65ACC in MRS broth within 96 h, consistent with the high production of bacteriocin throughout the analysis period (3,200-12,800 AU/mL). However, lower inhibitory activities of P. pentosaceus ST65ACC on L. monocytogenes Scott A were recorded in BHI, RSM, and meat broth, with low or no production of bacteriocins at the analyzed times. The composition of these culture media may have repressed the production and activity of bacteriocins and, consequently, the antagonist activity of P. pentosaceus ST65ACC on L. monocytogenes Scott A. The results showed that the antimicrobial activity was more effective in MRS broth, presenting greater production of bacteriocins and less variability when compared to the other media analyzed.
戊糖片球菌 ST65ACC 是从巴西传统奶酪中分离出来的具有抑菌活性的乳酸菌（LAB），能够抑制多种食源性病原体，主要是单核细胞增生李斯特菌。抑菌素的产生可以受到许多生长条件的影响，如温度、pH 值和培养基组成。本研究旨在评估不同培养基对戊糖片球菌 ST65ACC 抑菌素生产和对单核细胞增生李斯特菌 Scott A 抗菌活性的影响。将菌株单独和共培养接种于四种不同的培养基：BHI 肉汤、MRS 肉汤、肉汁和 10%（w/v）再水合脱脂乳（RSM）。然后将培养基在 37°C 下孵育 96 小时，并在 0、24、48、72 和 96 小时时进行计数分析、pH 值测量和抑菌素生产。在 96 小时内，MRS 肉汤中戊糖片球菌 ST65ACC 与单核细胞增生李斯特菌 Scott A 的共培养可将李斯特菌抑制至无法检测的水平，这与整个分析期间抑菌素的高产量（3,200-12,800 AU/mL）一致。然而，在 BHI、RSM 和肉汁中，戊糖片球菌 ST65ACC 对单核细胞增生李斯特菌 Scott A 的抑制活性较低，在分析时间内抑菌素的产量较低或没有。这些培养基的组成可能抑制了抑菌素的产生和活性，从而降低了戊糖片球菌 ST65ACC 对单核细胞增生李斯特菌 Scott A 的拮抗活性。结果表明，在 MRS 肉汤中的抗菌活性更有效，与分析的其他培养基相比，抑菌素的产量更高，变异性更小。
