Meza Guadalupe, Majrshi Hussain, Tiong Hung King
Department of Biological and Environmental Sciences, University of West Alabama, Livingston, AL 35470, USA.
Clinical Laboratory, Huntsville Hospital, Huntsville, AL 35801, USA.
Foods. 2022 Mar 7;11(5):764. doi: 10.3390/foods11050764.
Persistent Vibrio-parahaemolyticus-associated vibriosis cases, attributed, in part, to the inefficient techniques for detecting viable-but-non-culturable (VBNC) Vibrio pathogens and the ingestion of undercooked seafood, is the leading cause of bacterial seafood-borne outbreaks, hospitalizations, and deaths in the United States. The effect of extreme heat processing on Vibrio biology and its potential food safety implication has been underexplored. In the present work, environmental samples from the wet market, lagoon, and estuarine environments were analyzed for V. parahaemolyticus recovery using a modified, temperature-dependent, two-step enrichment method followed by culture-based isolation, phenotype, and genotype characterizations. The work recovered novel strains (30% of 12 isolates) of V. parahaemolyticus from prolonged-heat-processing conditions (80 °C, 20 min), as confirmed by 16S rDNA bacterial identification. Select strains, VHT1 and VHT2, were determined to be hemolysis- and urease-positive pathogens. PCR analyses of chromosomal DNA implicated the tdh-independent, tlh-associated hemolysis in these strains. Both strains exhibited significant, diverse antibiotic profiles (p < 0.05). Turbidimetric and viable count assays revealed the pasteurization-resistant V. parahaemolyticus VHT1/VHT2 (62 °C, 8 h). These findings disclose the efficiency of Vibrio extremist recovery by the modified, two-step enrichment technique and improve knowledge of Vibrio biology essential to food safety reformation.
在美国，持续性副溶血性弧菌相关的弧菌病病例部分归因于检测活的但不可培养（VBNC）弧菌病原体的技术效率低下以及食用未煮熟的海鲜，是细菌性食源性疾病暴发、住院和死亡的主要原因。极端热处理对弧菌生物学的影响及其潜在的食品安全影响尚未得到充分研究。在本研究中，使用改良的、温度依赖性的两步富集方法，随后进行基于培养的分离、表型和基因型鉴定，对来自湿市场、泻湖和河口环境的环境样本进行副溶血性弧菌回收率分析。通过16S rDNA细菌鉴定证实，该研究从长时间热处理条件（80°C，20分钟）中分离出了新型副溶血性弧菌菌株（12株中的30%）。选定的菌株VHT1和VHT2被确定为溶血和脲酶阳性病原体。对染色体DNA的PCR分析表明，这些菌株中的溶血与tdh无关，与tlh相关。两种菌株均表现出显著的、多样的抗生素谱（p<0.05）。比浊法和活菌计数法显示，副溶血性弧菌VHT1/VHT2具有巴氏杀菌抗性（62°C，8小时）。这些发现揭示了改良的两步富集技术在回收极端环境下弧菌方面的效率，并增进了对食品安全改革至关重要的弧菌生物学知识。
