Department of Biochemical and Pharmaceutical Technology Department, School of Pharmaceutical Sciences, University of São Paulo, Av. Lineu Prestes 580, São Paulo, 05508-900, Brazil.
Núcleo de Investigación en Producción Alimentaria. Departamento de Ciencias Biológicas y Químicas. Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco, Chile.
Mol Biol Rep. 2019 Oct;46(5):4883-4891. doi: 10.1007/s11033-019-04938-w. Epub 2019 Jun 26.
To improve bacteriocin-like inhibitory substance (BLIS) production by Pediococcus pentosaceus ATCC 43200, the influence of pH as well as the addition of sugars-either prebiotic (inulin) or not (sucrose)-on its metabolism were investigated. This strain was grown at pH 5.0 or 6.0 either in glucose-based MRS medium (control) or after addition of 0.5, 1.0 or 1.5% (w/w) sucrose and inulin (GSI-MRS) in the same percentages. In the control medium at pH 5.0, cell mass concentration after 48 h of fermentation (X = 2.26 g/L), maximum specific growth rate (µ = 0.180 h) and generation time (T = 3.84 h) were statistically coincident with those obtained in supplemented media. At pH 6.0 some variations occurred in these parameters between the control medium (X = 2.68 g/L; µ = 0.32 h; T = 2.17 h) and the above supplemented media (X = 1.90, 2.52 and 1.86 g/L; µ = 0.26, 0.33 and 0.32 h; T = 2.62, 2.06 and 2.11 h, respectively). Lactate production was remarkable at both pH values (13 and 16 g/L) and improved in all supplemented media, being 34 and 54% higher than in their respective control media, regardless of the concentration of these ingredients. Cell-free supernatant of the fermented control medium at pH 5.0 displayed an antimicrobial activity against Enterococcus 101 5.3% higher than that at pH 6.0 and even 20% higher than those of all supplemented media, regardless of the concentration of supplements. BLIS production was favored either at pH 5.0 or in the absence of any additional supplements, which were able, instead, to stimulate growth and lactate production by P. pentosaceus.
为了提高戊糖片球菌 ATCC 43200 产生细菌素样抑制物质 (BLIS) 的能力，研究了 pH 值以及添加糖（益生元菊粉或非糖蔗糖）对其代谢的影响。该菌株在 pH 5.0 或 6.0 下，在基于葡萄糖的 MRS 培养基（对照）或在添加 0.5%、1.0%或 1.5%（w/w）蔗糖和菊粉（GSI-MRS）的相同比例下生长。在 pH 5.0 的对照培养基中，发酵 48 小时后的细胞质量浓度（X=2.26 g/L）、最大比生长速率（µ=0.180 h）和世代时间（T=3.84 h）与补充培养基中获得的结果统计学一致。在 pH 6.0 下，这些参数在对照培养基（X=2.68 g/L；µ=0.32 h；T=2.17 h）和上述补充培养基（X=1.90、2.52 和 1.86 g/L；µ=0.26、0.33 和 0.32 h；T=2.62、2.06 和 2.11 h）之间存在一些差异。在两种 pH 值下（13 和 16 g/L）都有显著的乳酸生成，并且在所有补充培养基中都得到了改善，与各自的对照培养基相比，分别提高了 34%和 54%。在 pH 5.0 下发酵的对照培养基的无细胞上清液对肠球菌 101 的抗菌活性比 pH 6.0 高 5.3%，甚至比所有补充培养基的都高 20%，而与补充物的浓度无关。BLIS 的产生无论是在 pH 5.0 还是在没有任何额外补充物的情况下都得到了促进，而这些补充物能够刺激戊糖片球菌的生长和乳酸生成。
