超声波协同流水净化对克氏原螯虾中菌落总数及菌相构成的影响

目的:研究超声波协同流水净化对活体克氏原螯虾携带的细菌数量及菌相构成的影响。方法:测定了净化过程中克氏原螯虾壳+肉、腮部和肠道部位菌落总数变化,并应用随机扩增多态性DNA(random amplified polymorphic DNA,RAPD)指纹图谱结合16S rDNA测序鉴定分析龙虾在净化处理前后不同部位的菌相构成。结果:超声波协同流水处理能够显著减少虾壳+肉、腮和肠道部位的细菌载量,降低量分别达到2.18、2.23、1.01(lg(CFU/g))。挑取的218个单菌落中存在21种不同的RAPD谱型,不同谱型的细菌属于9个属18个种,其中气单胞菌属、黄杆菌属、嗜冷杆菌属、希瓦氏菌属和肠杆菌属细菌为虾壳肉和腮中的优势菌群,净化处理后虾中分布的细菌种群数降低为6个属9个种,其中温和气单胞菌(Aeromonas sobria)、阴沟肠杆菌(Enterobacter cloacae)、黄杆菌(Flavobacterium granuli)和腐败希瓦氏菌(Shewanella putrefaciens)是残留的优势细菌种群。结论:超声波协同流水净化对活体克氏原螯虾具有良好的减菌效果。

Effect of Synergistic Purification with Ultrasonic and Running Water on Bacterial Load and Microflora in Crawfish (Procambarus clarkii)

Objective: To examine the effect of synergistic purification with ultrasonic and running water on bacterial
quantity and community composition in live crawfish (Procambarus clarkii). Methods: The bacterial colony numbers in
the unshelled meat, grills and intestinal parts of crawfish were determined during the purification process and changes in
bacterial community composition were analyzed using random amplified polymorphic DNA (RAPD) fingerprint technique
combined with 16S rDNA sequencing identification. Results: The purification procedure by ultrasonic combined with
running water significantly reduced the bacterial loads in the unshelled meat, grills and intestine of crawfish to 2.18, 2.23
and 1.01 (lg (CFU/g)), respectively. A total of 218 single colonies were collected from bacterial counting plates, fingerprint
patterns of 21 colonies of which were obtained through RAPD analysis. The 16S rDNA sequencing identification showed
that the isolates with different fingerprint patterns belonged to 9 bacterial genera including 18 species, among which
Aeromonas sp., Flavobacterium sp., Pseudomonas sp., Shewanella sp. and Enterobacter sp. were the predominant bacterial
groups for crawfish shell, meat and gills. After being purified with ultrasonic and running water, the remaining bacterial
groups were reduced to 9 species from 6 genera, among which, Aeromonas sobria, Enterobacter cloacae, Flavobacterium
granuli and Shewanella putrefaciens were the major residual bacteria species. Conclusion: The synergistic purification with
ultrasonic and running water is highly effective in reducing bacterial level and species in live crawfish.