The Effects of Chemical and Mechanical Stresses on Bacillus cereus and Pseudomonas fluorescens Single- and Dual-Species Biofilm Removal

• Type: Article in International Scientific Journal
• Date: 2021

Authors

Madalena Lemos (Author) Other; Susana Fernandes (Author) Other; Anabela Borges (Author) FEUP; Lúcia C. Simões (Author) Other; Manuel Simões (Author) FEUP; Inês Gomes (Author) FEUP

Journal

Title: Microorganisms

Vol. 9 No. 6

Pages: 1-14

Publisher: MDPI

Indexing

ISI Web of Knowledge - 0 Citations

ISI Web of Science

Scopus - 0 Citations

Associated Projects

LEPABE - Financiamento Plurianual 2020-2023 da Unidade de I&D LEPABE - Laboratório de Engenharia de Processos, Ambiente, Biotecnologia e Energia

Biocide_for_Biofilm - Desenvolvimento de novas soluções biocidas para o controlo efetivo de biofilmes

GermIrrad - Sistema automatizado de irradiação germicida

Other information

Authenticus ID: P-00T-ZYZ

DOI: 10.3390/microorganisms9061174

Abstract (EN): Biofilm control is mainly based on chemical disinfection, without a clear understanding of the role of the biocides and process conditions on biofilm removal. This study aims to understand the effects of a biocide (benzyldimethyldodecyl ammonium chloride-BDMDAC) and mechanical treatment (an increase of shear stress -tau w) on single- and dual-species biofilms formed by Bacillus cereus and Pseudomonas fluorescens on high-density polyethene (HDPE). BDMDAC effects were initially assessed on bacterial physicochemical properties and initial adhesion ability. Then, mature biofilms were formed on a rotating cylinder reactor (RCR) for 7 days to assess the effects of chemical and mechanical treatments, and the combination of both on biofilm removal. The results demonstrated that the initial adhesion does not predict the formation of mature biofilms. It was observed that the dual-species biofilms were the most susceptible to BDMDAC exposure. The exposure to increasing tau w emphasised the mechanical stability of biofilms, as lower values of tau w (1.66 Pa) caused high biofilm erosion and higher tau w values (17.7 Pa) seem to compress the remaining biofilm. In general, the combination of BDMDAC and the mechanical treatment was synergic in increasing biofilm removal. However, these were insufficient to cause total biofilm removal (100%; an average standard deviation of 11% for the method accuracy should be considered) from HDPE.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 14