Biofilm detachment induced by various chemicals, including metal salts, surfactants and depolymerization agents, was investigated using an experimental system consisting of a two-species bacterial biofilm grown in continuous flow annular reactors. Two types of experiments were performed: 1) in situ environmental step change experiments conducted in annular biofilm reactors to examine detachment and 2) determination of viscometry of biofilm collected from these reactors. Experimental results showed that biofilm detachment could be induced by addition of various chemicals. Monovalent and divalent salts (including NaCl, CaCl2, MgCl2) were the most effective chemicals in changing biofilm structure, reflected by an average of 73% viscosity reduction. Directly performing step changes in biofilm reactors with these salts detached 40% of the biofilm in 75 minutes. Chelants showed similar results, e.g. 19.6% viscosity reduction and 26.3% biofilm detachment for EDTA. Surfactants (including sodium dodecyl sulfate, Triton X-100, Tween 20) also altered the structure of biofilm (e.g. viscosity reduction was 8.7% for Tween 20, 41.9% for Triton X-100, -12.6% for SDS) and caused a much larger amount of biofilm to detach (average of 61.7%). Addition of chlorine, monochloramine and some enzymatic lyases (including lysozyme and protease) caused viscosity reduction and biofilm detachment also. We found that 1) electrostatic (e.g., cation bridging) and hydrophobic interactions were two major forces that maintain the integrity of biofilm structure; 2) cells and EPS were the structural components of biofilms. Disruption of biofilm crosslinking forces and destruction of structural biofilm components could cause biofilm detachment.
Chemically induced biofilm detachment, Thesis Defense by Xiao Chen, PhD, Chemical Engineering, Montana State University, April 1998
Posted by dmc (Member # 5102) on :
just Needed to break up to read Dave6002's post
Biofilm detachment induced by various chemicals, including metal salts, surfactants and depolymerization agents, was investigated using an experimental system consisting of a two-species bacterial biofilm grown in continuous flow annular reactors.
Two types of experiments were performed:
1) in situ environmental step change experiments conducted in annular biofilm reactors to examine detachment and
2) determination of viscometry of biofilm collected from these reactors. Experimental results showed that biofilm detachment could be induced by addition of various chemicals.
Monovalent and divalent salts (including NaCl, CaCl2, MgCl2) were the most effective chemicals in changing biofilm structure, reflected by an average of 73% viscosity reduction.
Directly performing step changes in biofilm reactors with these salts detached 40% of the biofilm in 75 minutes. Chelants showed similar results, e.g. 19.6% viscosity reduction and 26.3% biofilm detachment for EDTA.
Surfactants (including sodium dodecyl sulfate, Triton X-100, Tween 20) also altered the structure of biofilm (e.g. viscosity reduction was 8.7% for Tween 20, 41.9% for Triton X-100, -12.6% for SDS) and caused a much larger amount of biofilm to detach (average of 61.7%).
Addition of chlorine, monochloramine and some enzymatic lyases (including lysozyme and protease) caused viscosity reduction and biofilm detachment also.
We found that 1) electrostatic (e.g., cation bridging) and hydrophobic interactions were two major forces that maintain the integrity of biofilm structure;
2) cells and EPS were the structural components of biofilms. Disruption of biofilm crosslinking forces and destruction of structural biofilm components could cause biofilm detachment.
Chemically induced biofilm detachment, Thesis Defense by Xiao Chen, PhD, Chemical Engineering, Montana State University, April 1998
Posted by Keebler (Member # 12673) on :
- Interesting but puzzling due to a few of things they use that may not be so kind to a human body.
Some things sound people-friendly but I'm thinking in that abstract that they are not taking about biofilm around germs in people but on and in laboratory equipment.
Lab equipment and instruments can have biofilm "stuck" to it. Cleaning it for the next test or function presents a challenge.
I don't have much of a science background and maybe this experiment is about people in the long run as they first have to figure out all the things that work, period - and then determine what is for equipment and what is for people (and the amount or combination can make all the difference, I suppose). -
Posted by Dave6002 (Member # 9064) on :
Thanks, dmc, for the breaking up.
Keebler, that's right: They are in vitro experiments. However,read this Monovalent and divalent salts (including NaCl, CaCl2, MgCl2) were the most effective chemicals in changing biofilm structure, reflected by an average of 73% viscosity reduction. suggesting that the salt/c may help breaking up biofilm in the body.
Surfactants (including sodium dodecyl sulfate, Triton X-100, Tween 20) also altered the structure of biofilm (e.g. viscosity reduction was 8.7% for Tween 20, 41.9% for Triton X-100, -12.6% for SDS) and caused a much larger amount of biofilm to detach (average of 61.7%).
I put some Tween 20 (Polysorbate 20) into Salt/C solution at 1% concentration and ingested. I may have some positive results: my hand-foot pains are greatly reduced, although I experienced some Herx reactions at the beginning.
Tween 20 is a detergent whose stability and relative non-toxicity allows it to be used as a detergent and emulsifier in a number of domestic, scientific, and pharmacological applications.
Posted by Keebler (Member # 12673) on :
- Have you used Grapefruit Seed Extract? That is a good emulsifier from a completely natural source that is used to help counteract biofilm for lyme patients.
Nattokinase, Lumbrokinase, Serrapeptase and similar enzymes, as well as Wobenzyme, also help.
Sea Salt & Vitamin C, likely, could be used in conjunction with any of those, if desired. -
Posted by Dave6002 (Member # 9064) on :
Keebler, thanks. No I have not used Grapefruit Seed Extract. I didn't know that Grapefruit Seed Extract is a emulsifier.
Maybe I should give it a try.
Posted by Dave6002 (Member # 9064) on :
Abstract
Biofilm protein removal by a variety of chemical treatments was investigated.
Binary population biofilms of P. aeruginosa and K. pneumoniae were grown in continuous flow annular reactors for 7�9 days prior to a 1-h treatment period.
Treatments that caused removal of more than 25% of the biomass (as total protein) included NaCl and CaCl2, two chelating agents (EDTA and Dequest 2006), surfactants (SDS, Tween 20, and Triton X-100), a pH increase, lysozyme, hypochlorite, monochloramine, and concentrated urea.
Treatments that caused little removal (less than 25%) included a control, MgCl2, sucrose, nutrient upshifts and downshifts, and a pH decrease.
The amount of biofilm protein removal and the reduction in viable cell numbers in the biofilm were not correlated. Some treatments caused significant killing but not much removal while other treatments caused removal with little killing.
These results underscore the fact that biofilm removal and killing are distinct processes.
The chemical diversity of agents that bring about biofilm removal suggests that multiple interactive forces contribute to biofilm cohesion.
No pattern of differential removal of the two microbial species could be discerned