Abstract: In this study, the effects of heat shock-repair combined with addition of trehalose in lyoprotectant on the freeze-drying resistance and room temperature storage stability of Lactiplantibacillus plantarum LIP-1 were investigated. The results showed that the freeze-drying survival rate of the combined treatment group with heat shock-repair and 4 g/100 mL trehalose addition was 81.65%, which was significantly higher than those of the control group without heat shock-repair treatment (59.92%) and the heat shock-repair treatment group (70.23%) (P < 0.05). The damage degree of cell wall and cell membrane in the combined treatment group was significantly reduced compared with that in the control group. The addition of trehalose maintained a high proportion of unsaturated fatty acids in the cell membrane, reduced cell membrane damage, and significantly enhanced the freeze-drying resistance of the strain while improving its room temperature storage stability. After eight weeks of storage, the survival rate of the combined treatment group was 51.66%, which was significantly higher than those of the control (12.09%) and heat shock-repair (43.79%) groups (P < 0.05), and the intracellular fluorescence intensity was 1 969.23 ± 37.22, which was significantly lower than those in the control (3 475.21 ± 106.56) and heat shock-repair (2 843.95 ± 52.12) groups (P < 0.05). To sum up, the combined treatment could improve the freeze-drying resistance and room temperature storage stability of the strain.

Key words: Lactiplantibacillus plantarum LIP-1; heat shock-repair; trehalose; freeze-drying survival rate; storage stability at room temperature

摘要： 以植物乳植杆菌LIP-1为研究对象，探究热激-修复与保护剂中添加海藻糖联合处理对菌株冷冻干燥抗性及常温贮藏稳定性的影响。结果表明：与未进行热激-修复处理的空白组（59.92%）和只进行热激-修复处理的对照组（70.23%）相比，经热激-修复与4 g/100 mL海藻糖联合处理的实验组菌株冷冻干燥存活率（81.65%）显著升高（P＜0.05），探究其原因发现，实验组菌株细胞壁与细胞膜损伤程度与对照组相比显著降低，保护剂中添加海藻糖可使细胞膜不饱和脂肪酸占比维持在较高水平，减少细胞膜损伤，显著增强菌株的冷冻干燥抗性；同时，菌株在常温贮藏期间的稳定性也得到提高，第8周贮藏期结束时，实验组菌株存活率为51.66%，显著高于空白组（12.09%）和对照组（43.79%）（P＜0.05），且实验组菌株胞内荧光强度（1?969.23±37.22）显著低于空白组（3?475.21±106.56）和对照组（2?843.95±52.12）（P＜0.05）。综上，热激-修复与保护剂中添加4 g/100 mL海藻糖联合处理可以提高菌株冷冻干燥抗性及常温贮藏稳定性。

关键词: 植物乳植杆菌LIP-1；热激-修复；海藻糖；冷冻干燥存活率；常温贮藏稳定性