Department of Comparative Biomedicine and Food Science, University of Padova, Agripolis, Viale dell'Università 16, Legnaro, 35020, Italy.
Associazione "Vongola Verace di Chioggia", Italy.
Environ Microbiol. 2020 Oct;22(10):4456-4472. doi: 10.1111/1462-2920.15196. Epub 2020 Sep 9.
As filter-feeders, bivalve molluscs accumulate Vibrio into edible tissues. Consequently, an accurate assessment of depuration procedures and the characterization of the persistent Vibrio community in depurated shellfish represent a key issue to guarantee food safety in shellfish products. The present study investigated changes in the natural Vibrio community composition of the Ruditapes philippinarum microbiota with specific focus on human pathogenic species. For this purpose, the study proposed a MLSA-NGS approach (rRNA 16S, recA and pyrH) for the detection and identification of Vibrio species. Clam microbiota were analysed before and after depuration procedures performed in four depuration plants, using culture-dependent and independent approaches. Microbiological counts and NGS data revealed differences in terms of both contamination load and Vibrio community between depuration plants. The novel MLSA-NGS approach allowed for a clear definition of the Vibrio species specific to each depuration plant. Specifically, depurated clam microbiota showed presence of human pathogenic species. Ozone treatments and the density of clams in the depuration tank probably influenced the level of contamination and the Vibrio community composition. The composition of Vibrio community specific to each plant should be carefully evaluated during the risk assessment to guarantee a food-safe shellfish-product for the consumer.
作为滤食性动物,双壳贝类将弧菌积累到可食用组织中。因此,准确评估净化程序和描述净化贝类中持续存在的弧菌群落特征是保证贝类食品安全的关键问题。本研究调查了菲律宾蛤仔微生物群中自然弧菌群落组成的变化,特别关注人类致病性物种。为此,本研究提出了一种 MLSA-NGS 方法(rRNA 16S、recA 和 pyrH)用于检测和鉴定弧菌。使用依赖和独立的方法,在四个净化厂进行净化程序前后,对蛤仔微生物群进行了分析。微生物计数和 NGS 数据显示,在净化厂之间,无论是污染负荷还是弧菌群落,都存在差异。新的 MLSA-NGS 方法可以清楚地定义每个净化厂特有的弧菌物种。具体来说,净化后的蛤仔微生物群中存在人类致病性物种。臭氧处理和净化槽中蛤仔的密度可能影响污染水平和弧菌群落组成。在进行风险评估时,应仔细评估每个工厂特有的弧菌群落组成,以保证消费者食用安全的贝类产品。