不同血清型副溶血性弧菌生长预测模型研究

Growth prediction models of Vibrio parahaemolyticus with different serotypes

中文关键词:  副溶血性弧菌  血清型  生长预测模型

英文关键词:Vibrio parahaemolyticus  serotype  growth prediction model

中文摘要:

      目的 研究不同血清型的副溶血性弧菌(Vibrio parahaemolyticus, VP)在不同培养条件下的生长异质性, 并建立流行株(血清型O3:K6、O10:K4)的生长预测模型。方法 选取17株不同血清型的VP菌株为研究对象, 设置不同培养条件, 包括盐度(0.5%~10.0%)、pH (3.0~11.0)和温度(16~50 ℃), 采用修正的Gompertz模型建立其一级生长模型, 比较其最大生长OD值(Ymax)、延滞期(λ)和最大比生长速率(μmax)确定其最适生长范围, 用Design-Expert 13软件建立其二级响应面生长模型。结果 VP菌株之间存在生长异质性, 在盐度为1.0%~3.0%、pH为7.0~9.0、温度为20~40 ℃时菌株生长参数μmax和Ymax之间的变异系数低于其他培养条件, 盐度为7.0%、pH为10.0、温度为16 ℃时流行株(血清型为O3:K6、O10:K4)的生长能力强于其他血清型菌株, 存在显著性差异(P<0.05); 不同盐度和温度下拟合的一级生长模型的决定系数均大于0.98, 不同酸碱度下相关系数均大于0.9; 二级响应面生长模型是显著的(P<0.05), 决定系数均大于0.94。结论 VP菌株之间存在生长异质性, 但在某些极端条件下, 不同血清型之间会表现出更明显的生长差异, 修正的Gompertz模型和二级响应面生长模型适用于分析和预测不同实验条件下VP的生长情况, 可以为VP的生长趋势提供可靠安全的预测。

英文摘要:

      Objective To study the growth heterogeneity of different serotypes of Vibrio parahaemolyticus (VP) under different culture conditions, and to establish growth prediction models for epidemic strains (O3:K6, O10:K4). Methods Seventeen VP strains of different serotypes were selected as the research objects, and different culture conditions were set, including salinity (0.5%–10.0%), pH (3.0–11.0) and temperature (16–50 ℃). The modified Gompertz model was used to establish the primary growth model. The optimal growth range was determined by comparing the maximum OD value (Ymax), the Lag time (λ) and maximum specific growth rate (μmax). The second-order response surface growth model was established by Design-Expert 13 software. Results There was growth heterogeneity among VP strains. The coefficient of variation for differences in growth parameters μmax and Ymax between VP strains at salinity levels of 1.0%–3.0%, pH of 7.0–9.0, and temperatures of 20–40 ℃ was lower than that under other culture conditions. The growth ability of the epidemic strains (serotype O3:K6, O10:K4) was significantly greater than that of other serotypes when the salinity was 7.0%, the pH was 10.0, and the temperature was 16 ℃, with a statistically significant difference (P<0.05). The determination coefficients of the first-order growth models fitted under different salinity and temperature were greater than 0.98, and the correlation coefficients under different pH were greater than 0.9. The second-order response surface growth model was significant (P<0.05), and the determination coefficient was greater than 0.94. Conclusion There is growth heterogeneity among VP strains, but in certain extreme conditions, there are more obvious growth differences between different serotypes. The modified Gompertz model and the second-order response surface growth model can be used to analyze and predict the growth of VP under different experimental conditions, which can provide reliable and safe prediction for the growth trend of VP.