F6PPK酶法分析双歧杆菌类产品中双歧杆菌活菌数

F6PPK Enzymatic Analysis of Bifidobacterium Viable Count in Bifidobacterium Products

果糖-6-磷酸磷酸酮解酶(F6PPK)是双歧杆菌属细菌所特有的糖类代谢的酶。对不同菌株F6PPK酶活力测定结果表明:F6PPK酶活力可作为双歧杆菌存在的标识物。通过测定不同培养时间的双歧杆菌培养物的F6PPK酶活力及双歧杆菌活菌数,表明在两歧双歧杆菌和长双歧杆菌中,F6PPK酶活力与双歧杆菌活菌数之间存在线性关系。建立这两种双歧杆菌的F6PPK酶活力-双歧杆菌活菌数之间的工作曲线。以金双歧片剂和合生元儿童益生菌冲剂产品为例,根据该工作曲线,测定产品的F6PPK酶活力,即可计算得到产品所含双歧杆菌数量。本研究建立的F6PPK酶法分析双歧杆菌数量的方法不依赖于厌氧箱平板培养,具有快速、方便的特点,特别适用于仅含1种双歧杆菌的混合菌制品的分析。

Fructose-6-phosphate phosphoketolase （F6PPK） is a Bifidobacterium genus-specific enzyme involved in carbohydrate metabolism. In this work F6PPK activity was confirmed to be an indicator of the existence of Bifidobacterium by investigating various strains＇ F6PPK activity. Bifidobacterium cultures taken at different incubation time were used to analyze their F6PPK activity and viable count, and the linear correlation between F6PPK activity and Bifidobacterium viable count was proved to exist both in Bifidobacterium bifidum and in Bifidobacterium longum. Then the working curve between F6PPK activity and Bifidobacterium viable count of these 2 species was built up. Taking the Bifidobacterium products of Golden Bifid tablet and Biostime Probiotics Sachet for Children as examples, the Bifidobacterium viable count in products was figured out based on the working curve by only analyzing their F6PPK activity. The F6PPK enzymatic method for analyzing Bifidobacterium viable count established in this work does not depend on plate cultivation process performed in anaerobic incubator, therefore fast and convenient. It is especially suitable for analysis of those mixed probiotics products with only 1 species of Bifidobacterium in them.