Song J, Qin Q, Li T, Ren F, Zhang H, Xie Y, Jin J
Food Science and Engineering College, Beijing University of Agriculture, Beijing Laboratory of Food Quality and Safety, Beijing Key Laboratory of Detection and Control of Spoilage Organisms and Pesticide Residues in Agricultural Products, Beijing, China.
China Youth University for Political Sciences, Beijing, China.
Lett Appl Microbiol. 2018 Apr;66(4):340-346. doi: 10.1111/lam.12854. Epub 2018 Feb 22.
In this study, the regularity of autoinducer-2 (AI-2) secretion during growth and the effect of the addition of various carbohydrates on AI-2 secretion in Bifidobacterium longum subsp. longum BBMN68 were investigated. The results indicated that the AI-2 concentration reached its highest level (2536·60 nmol l ) at the early stationary growth phase, and then decreased to 1263·72 nmol l at the late stationary growth phase in Bifidobacterium cultures. When the density of the cultures which mannose, fructose, sucrose and lactose had been added to reached an OD of 1·0, the AI-2 concentrations in the cultures were 1953·84, 1637·34, 1200·99 and 1077·60 nmol l , respectively. These concentrations were all significantly higher than that of the control culture (1031·33 nmol l ). Similarly, the addition of fructooligosaccharide significantly increased the AI-2 concentrations to 2094·29 nmol l . This study provides the advanced evidence that certain carbohydrates promote the secretion of AI-2, and that this occurs at the single cell level and is therefore unaffected by cell density.
This study provided the advanced data of the regularity of autoinducer-2 (AI-2) secretion during growth and the promotion on AI-2 secretion of different added carbohydrates in Bifidobacterium, which may be a new potential strategy to improve the acid resistance of Bifidobacterium applied in the food industry.
在本研究中，调查了长双歧杆菌亚种长双歧杆菌BBMN68生长过程中自诱导物-2（AI-2）的分泌规律以及添加各种碳水化合物对AI-2分泌的影响。结果表明，在双歧杆菌培养物中，AI-2浓度在生长稳定前期达到最高水平（2536.60 nmol/L），然后在生长稳定后期降至1263.72 nmol/L。当添加了甘露糖、果糖、蔗糖和乳糖的培养物密度达到OD值为1.0时，培养物中的AI-2浓度分别为1953.84、1637.34、1200.99和1077.60 nmol/L。这些浓度均显著高于对照培养物（1031.33 nmol/L）。同样，添加低聚果糖显著提高AI-2浓度至2094.29 nmol/L。本研究提供了高级证据，证明某些碳水化合物可促进AI-2的分泌，且这种促进作用发生在单细胞水平，因此不受细胞密度的影响。
本研究提供了关于自诱导物-2（AI-2）在生长过程中分泌规律以及不同添加碳水化合物对双歧杆菌AI-2分泌促进作用的高级数据，这可能是提高应用于食品工业的双歧杆菌耐酸性的一种新的潜在策略。
