Tanaka Yoshihiro, Naganawa Masayuki, Sakai Masatoshi, Saito Shigeru
Meijiyakuhin Co., Ltd., Technical Development, 6 Sango, Toyama-city, Toyama 939-3548, Japan.
Rinsho Biseibutshu Jinsoku Shindan Kenkyukai Shi. 2006;17(1):23-32.
To investigate the specificity of a newly developed Lactobacillus medium (LB medium) and its usefulness for the detection of Lactobacillus.
Chlorophenol red was added to Rogosa SL Broth to make the LB medium whose pH was adjusted to 5.90. After incubation of Lactobacillus in LB medium for 24 hours, the correlation between the number of bacteria and the medium pH was examined. The change of pH was also examined when other microbes coexisted with Lactobacillus.
Six species of Lactobacillus were tested. The medium pH decreased to 4 approximately 5 after incubation of any of these species for 24 hours. Though there were some differences in the acid-producing ability among species, a significant negative correlation (r = -0.93 approximately -0.99) was found between the initial number of bacteria and the medium pH with all species tested. The color of the medium did not change after incubation of other bacteria that might also be found in the normal vagina. The performance of the medium was not affected by the presence of large numbers of other microbes. In L. gasseri JCM 1131, the test microbe for color sample, the number of microbes whose color changed (red-->orange-->yellow) were approximately consistent with that of microbes reported in bacterial vaginosis (BV).
This method can be easily applied to detect Lactobacillus species as the number of Lactobacillus can be estimated based on the change in color of the medium for less than 24 hours after incubation.
研究新开发的乳酸杆菌培养基（LB培养基）的特异性及其在检测乳酸杆菌方面的实用性。
向罗戈萨SL肉汤中添加氯酚红制成LB培养基，将其pH值调至5.90。将乳酸杆菌在LB培养基中培养24小时后，检测细菌数量与培养基pH值之间的相关性。当其他微生物与乳酸杆菌共存时，也检测pH值的变化。
测试了六种乳酸杆菌。将其中任何一种培养24小时后，培养基pH值降至约4至5。尽管不同菌种产酸能力存在一些差异，但在所测试的所有菌种中，初始细菌数量与培养基pH值之间均发现显著的负相关（r = -0.93至-0.99）。正常阴道中可能存在的其他细菌培养后，培养基颜色未发生变化。大量其他微生物的存在不影响该培养基的性能。在加氏乳杆菌JCM 1131（颜色样本的测试微生物）中，颜色发生变化（红色→橙色→黄色）的微生物数量与细菌性阴道病（BV）中报道的微生物数量大致一致。
该方法可轻松应用于检测乳酸杆菌菌种，因为培养不到24小时后，可根据培养基颜色变化估计乳酸杆菌数量。
