Martinez Rafael Chacon Ruiz, Staliano Cristina Dini, Vieira Antonio Diogo Silva, Villarreal Martha Lissete Morales, Todorov Svetoslav Dimitrov, Saad Susana Marta Isay, Franco Bernadette Dora Gombossy de Melo
Department of Food and Experimental Nutrition, School of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, B14, 05508-000, São Paulo, SP, Brazil.
Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, B16, 05508-000, São Paulo, SP, Brazil.
Food Microbiol. 2015 Jun;48:143-52. doi: 10.1016/j.fm.2014.12.010. Epub 2015 Jan 5.
Survival, bacteriocin(s) production, and antilisterial effect of Lactobacillus sakei subsp. sakei 2a were evaluated in a potentially synbiotic cheese spread, throughout storage at 4 °C and 15 °C for up to 28 days, using culture-dependent (plate count) and culture-independent (qPCR) methods. Bacteriocin(s) production in the food product was monitored by phenotypic and molecular (RT-qPCR) techniques. Three cheese spread trials (T) containing the prebiotic fiber inulin were produced in duplicates and studied: T1 (control - without inoculation of lactic acid bacteria); T2 (inoculated with the non-bacteriocinogenic Lb. sakei ATCC 15521 strain), and T3 (inoculated with the bacteriocinogenic Lb. sakei 2a strain). The cheese spreads were challenged with Listeria monocytogenes serotypes 4b and 1/2a, individually added to the food product. The counts of Lb. sakei 2a in the cheese spread T3 remained high during storage and the growth of L. monocytogenes was inhibited at both temperatures, especially L. monocytogenes 4b in the food product kept at 15 °C due to the production of bacteriocins (up to 6,400 AU/mL). Expression of the genes sakP and sakQ encoding for bacteriocins production during the cheese spread storage was demonstrated. Lb. sakei 2a can be used for production of potentially synbiotic cheese spreads with increased safety.
在一种潜在的合生元奶酪酱中，使用基于培养的（平板计数）和非培养的（qPCR）方法，评估了清酒乳杆菌清酒亚种2a在4°C和15°C下储存长达28天期间的存活率、细菌素产生情况及抗李斯特菌效果。通过表型和分子（RT-qPCR）技术监测食品中细菌素的产生。制备了三份含有益生元纤维菊粉的奶酪酱试验样品（T），每份样品做两个重复并进行研究：T1（对照 - 未接种乳酸菌）；T2（接种非产细菌素的清酒乳杆菌ATCC 15521菌株），以及T3（接种产细菌素的清酒乳杆菌2a菌株）。将单核细胞增生李斯特菌4b和1/2a血清型分别添加到食品中，对奶酪酱进行挑战试验。在储存期间，奶酪酱T3中的清酒乳杆菌2a数量保持较高水平，并且在两个温度下，单核细胞增生李斯特菌的生长均受到抑制，尤其是在15°C保存的食品中的单核细胞增生李斯特菌4b，这是由于细菌素的产生（高达6400 AU/mL）。在奶酪酱储存期间，证明了编码细菌素产生的基因sakP和sakQ的表达。清酒乳杆菌2a可用于生产安全性更高的潜在合生元奶酪酱。
