Lapierre L, Undeland P, Cox L J
Quality and Safety Assurance Department, Nestec Ltd., Nestlé Research Center, Vers-Chez-les-Blanc, Switzerland.
J Dairy Sci. 1992 May;75(5):1192-6. doi: 10.3168/jds.S0022-0302(92)77866-7.
Lithium chloride-sodium propionate agar has been developed for the enumeration of bifidobacteria in fermented dairy products. The medium contains lithium chloride and sodium propionate to inhibit the growth of other lactic acid bacteria. Pure cultures of bifidobacteria, lactobacilli, and streptococci were tested for growth in this medium. With one exception, all bifidobacteria were able to grow in this medium and in a nonselective agar with a difference not exceeding .4 log units. However, none of the lactobacilli tested and only one strain each of Streptococcus salivarius ssp. thermophilus and Lactococcus lactis ssp. cremoris grew in lithium chloride-sodium propionate agar. In those cases, the numbers of colonies were lower in lithium chloride-sodium propionate agar by 1.26 and 2.51 log units, respectively, compared with a nonselective agar. Bifidobacteria were also selectively isolated from all fermented milks and cheeses analyzed.
氯化锂-丙酸钠琼脂已被开发用于对发酵乳制品中的双歧杆菌进行计数。该培养基含有氯化锂和丙酸钠以抑制其他乳酸菌的生长。对双歧杆菌、乳酸杆菌和链球菌的纯培养物在这种培养基中的生长情况进行了测试。除了一个例外，所有双歧杆菌都能够在这种培养基以及在差异不超过0.4个对数单位的非选择性琼脂中生长。然而，所测试的乳酸杆菌均不能生长，唾液链球菌嗜热亚种和乳酸乳球菌乳脂亚种各只有一个菌株能在氯化锂-丙酸钠琼脂中生长。在这些情况下，与非选择性琼脂相比，氯化锂-丙酸钠琼脂中的菌落数分别低1.26和2.51个对数单位。双歧杆菌也从所有分析的发酵乳和奶酪中被选择性地分离出来。
