Induction of viable but putative non-culturable Lactobacillus acetotolerans by thermosonication and its characteristics
Induction of viable but putative non-culturable Lactobacillus acetotolerans by thermosonication and its characteristics
复制标题
热超声诱导存活但推定不可培养的乙酰耐受乳杆菌及其特性
DOI：
10.1016/j.lwt.2019.04.046
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Yang Deng
中科院分区：
文献类型：
--
作者：
Meizi Piao;Yan Li;Ying Wang;Fengwu Wang;Tianyuan Zhen;Yang Deng
This study aimed at investigating for the first time whether thermosonication (TS), a non-thermal processing technique, could induce the beer-spoilage bacterium,LactobacillusacetotoleransCGMCC 7.150, into the viable but putatively non-culturable (VPNC) state. After determining culturable, viable and total cell counts, we found thatL. acetotoleransin beer could enter the VPNC state by TS at a constant frequency of 24 kHz at 50 °C at three relatively low volumetric powers (0.6, 1.2 and 1.8 W/mL, but not 2.4 W/mL). Furthermore, with the increase of volumetric power, the time required forL. acetotoleranscells to enter the VPNC state shortened. The addition of Tween 80 at a concentration of 0.1% v/v into de Man Rogosa Sharpe agar enabled the VPNC cells to regain culturability with a recovery time of approximately 3 days. However, their recovery capability decreased with the increasing volumetric power. Scanning electron microscopy analysis showed that cells decreased in size and gradually changed morphology from short rods to coccoids upon entering the VPNC state. An insignificant difference in beer-spoilage ability was found between the exponential-phase and VPNC cells. The resistance of these VPNC cells to 0.025 M NaOH and 0.025 M KOH was enhanced compared with the exponential-phase cells.
