Bio Fouling

(Biological fouling)

Undesired deposition of material Inorganic fouling on surfaces Materials obtained fro

organic matter of soil produce by decomposition of plant o animal matte

Precipitation of inorganic crystals

Organic fouling Deposition of fat, oil, protein etc

Particle fouling Deposition of clay, humic particles etc

Biofouling

Deposition and growth of microorganis on surfaces – particles that can multiply the expense of nutrie

Undesired accumulation of microorganisms, plants, algae and animals  Why is this important?  What are the effects of biofouling?  Why should we study this? Because Biofouling has a bright future

Slime and mold behind washing soap intake box Slime formation in tubes Clothes are smelly if not dried properly

Toilet rinsing water reservoir red and dark brown colour: Bacterial and fungal biofilms in Calciferous incrustations Potential problem: Dispersion of aerosols when flushing

Inner tubes of showers

Keratitis due to non-compatible biofilm on contact lense

Biofouling on teeth: cause for bad smell and caries

Biofouling in dialysis unit Microbial contamination of an injection syringe

Contamination pathways in catheter application

Hole due to slime

Biofouling in Paper mills

Biofouling: a serious problem for cooling cycles in energy industry Reduced Heat transfer ncreased Drag resistance Biocorrosion

Biofouling in water supply

 Also in power stations

Fouling community Micro fouling • Biofilm formation • Bacterial adhesion

Macro fouling

Attachment of layer organisms Ex: Barnacles Anthropod in sea Mussels Many bristles for attachmentPolychaete worms Bryozoans – sea mats Sea weeds

Biofouling affects ships severly Leads to • Decreased carrying capacity • Increased (30%) fuel consumption • Increased cost in maintenance of shipping industry • Increased (50%) marine transport cost

How to tackle the problem? Antifouling Strategies?

Remove accumulation

Prevent accumulation Not so effective

• Primarily used – “Organotins” (Tin with hydrocarbons) • Most widely used example for organotins – “TBT” or “TPT” Tri Butyl Tin Tri Phenyl Tin

• Most commonly used antifouling agent • Used as coatings in ships • Very effective – Get rid of biofouling once forever

Coatings toxic to marine environment So used in lower concentration – not effective

an d

Defective shell growth in Oyster (> 20 ng/l) Before

After

• Development of male characters in female dog whelk (> 1 ng/l)

So, organotins banned !

Then what are the other methods? • Cupronickels (Cu – 90% & Nickels – 10%) – tried for biofouling prevention. Safety yet to be proved. • Selection of metals – Ex. Zebra mussels find Aluminium bronze distasteful. So they avoid such metals Disadvantages • Not effective in ships that travel long distance • Biological and chemical nature of microorganisms must be studied

Other methods… • Titanium • Chlorination • Pulse laser irradiation – not species specific

Fight nature with nature itself (from worms) – 1.Nemertine pyridyl alkaloids may be used for inhibition of Barnacle larvae 2. Purified extract from Carribean sponges – inhibit bacterial attachment 3. Distaplia nathensis extract – inhibits mussel 4. Pseudoalteromonas sp. (marine bacteria) – produces bioactive compounds with inhibitory effect on algae and on barnacles

All the best - Benedict