INVESTIGATIONS ON THE PROBABILITY OF BIOMINERALISATION OF EXPOSED TO THE COASTAL WATERS OF KALPAKKAM

Transcription

1 INVESTIGATIONS ON THE PROBABILITY OF BIOMINERALISATION OF MANGANESE ON TITANIUM SURFACES EXPOSED TO THE COASTAL WATERS OF KALPAKKAM R.P.GEORGE, JUDY GOPAL, P.MURALEEDHARAN, H. SARVAMANGALA*, R.K. DAYAL, B.V.R. TATA AND K.A. NATARAJAN* Metallurgy and Materials Group, IGCAR, Kalpakkam * Department t of Metallurgy, IISc, Bangalore

2 TITANIUM AS CONDENSER MATERIAL BIOFOULING AND BIOMINERALISATION Mn 2+ SEA WATER Mn 2+ Mn 2+ Mn 2+ Mn 4+ Mn 4+

3 DOES THIS PROBLEM REALLY EXIST?? HOW TO IDENTIFY THE PROBLEM WHAT IS THE EXTENT OF THE PROBLEM???

4 BIOFILM FORMATION ON TITANIUM SURFACES EXPOSED TO SEAWATER Before EXPOSING 24h 48h 72h 3Day 4Day

5 SERPULIDS POLYCHAETE WORM 2 month biofilm 3 month biofilm

6 Confocal Laser Scanning Microscopic Images 1 week old biofilm 1 year old biofilm

7 MICROBIAL CONTENT OF THE BIOFILM Vs EXPOSURE TIME Marine bacteria Manganese oxdizing bacteria 10 5 cfu/cm Exposure time (Months)

8 EPS CONTENT OF THE BIOFILM Vs EXPOSURE TIME Protein Carbohydrate 100 mg/m ml EXPOSURE(MONTHS)

9 SPECIFIC MEDIUM FOR ISOLATION OF MOB 0.5g of yeast extract liter gof Casamino acids liter -1 1g of glucose liter g of HEPES buffer liter -1 2 x 10-3 M CaCl x 10-3 M MgSO x 10-3 M MnCl x 10-6 M FeCl 3 1 l f t l t l ti lit 1 1ml of trace element solution liter -1. (concentrations in mg liter -1,are given in parenthesis): CuSO 4. 5H 2 O, (44) ZnSO 4. 7 H 2 O, (20) CoCl 2. 6H 2 O and (13) Na 2 MoO 4. 2 H 2 O.

10 SCREENING OF MOB IN SOLID MEDIA

11 S.No MARINE ISOLATE BACTERIAL GENUS Browning of colonies on POLYCARBONATE MEMBRANE 1. 1W M11 + VE 2. 1W M8 +VE 3. 1M 3M +VE 4. 1M A7 +VE 5. 1M A3 +VE 6. 2M A11 WEAKLY +VE 7. 3M M3 +VE 8. 3M S11 WEAKLY +VE 9. 3M M2 -VE 10. 5M BS -VE 11. 5M 17 +VE 12. 6M 3 STRONGLY +ve 13. 6M 5 +VE 14. 6M 8 +VE 15. 6M 12 +VE strong ly +ve colonies are intensely brown +ve colonies are brown weakly +ve colonies are light brown - ve colonies show no brown coloration

12 THE ABILITY OF THE MARINE ISOLATES TO OXIDIZE MANGANESE WAS TESTED UNDER LABORATORY CONDITIONS SCREENING THE MARINE ISOLATES FOR THEIR ABILITY TO OXIDIZE Mn IN LIQUID BROTH 50ppm OF Mn 2+ WAS ADDED TO GROWTH MEDIUM CONTAINING BACTERIAL CULTURES THE UNREACTED Mn 2+ WAS ANALYSED USING ICP-AES

13 MANGANESE OXIDATION IN LIQUID BROTH

14 RESULTS OF ICP-AES ANALYSIS Biofilmisolated from Marine isolates Mn 2+ remaining in solution 3 Month 3MS ppm 3 Month 3MS ppm 3 Month 3MS11 0 ppm 3Month 3MS13 447ppm Month 3MM1 0 ppm 3 Month 3MM ppm 4 Month 4MS ppm 4 Month 4MS ppm 4Month 4MS3 0008ppm Month 4MS ppm 4 Month 4MS ppm 4M Month 4MS8 0 ppm

15 BACTERIA ISOLATED DURING THE STUDY LIST OF MARINE MANGANESE MARINE SULPHATE REDUCING OXIDISING BACTERIA ISOLATED BACTERIA ISOLATED FROM FROM TITANIUM SURFACES BIOFILM FORMED ON TITANIUM SURFACES species belonging to Bacillus 3 species belonging to Desulfovibrio species belonging to Pseudomonas 2 species belonging to Desulfotomaculum 3. 4 species belonging to Micrococcus 4. 4 species belonging to Vibrio 5. 5 species belonging to Arthrobacter 6. 2 species belonging to Staphylococcus 7. Citrobacter spp 8. Hyphomicrobium spp 9. E.coli 10. Pedomicromium spp 11. Flavobacterium spp.

16 OPTICAL MICROGRAPH OF FREQUENTLY OCCURING MANGANESE OXIDIZING BACTERIA Pseudomonas spp

17 OPTICAL MICROGRAPH OF FREQUENTLY OCCURING MANGANESE OXIDIZING BACTERIA Bacillus spp

18 OPTICAL MICROGRAPH OF FREQUENTLY OCCURING MANGANESE OXIDIZING BACTERIA Vibrio spp Vibrio spp Vibrio spp Pedomicrobium spp Arthrobacter spp Arthrobacter spp Arthrobacter spp Staphylococcus spp Micrococcus spp Micrococcus spp Micrococcus spp Hyphomicrobium spp

19 FREQUENCY OCCURRENCE OF MARINE MOB ON TITANIUM BIOFILMS

20 UNDERSTANDING THE KINETICS OF MANGANESE OXIDATION BY PREDOMINANTLY OCCURING BACILLUS SPP.

21 50 Mn (mg / L) in solution M arine isolate Control Time (hours) MANGANESE OXIDATION IN THE PRESENCE AND ABSENCE OF BACTERIAL CELLS

22 MANGANESE OXIDATION BY BACILLUS SPP 50 Mn (m mg / L) in solution Growing culture + MnCl 2 Grown culture + MnCl 2 M etabolite Heat treated metabolite Time (hours)

23 16µm particle size 7µm particle size SEM CHEMICAL MnO 2 BIOGENIC MnO 2 EDAX

24 ICPAAS RESULTS OF BIOFILM FORMED ON TITANIUM EXPOSED TO SEAWATER

25 EXPERIMENTS TO INVESTIGATE THE PROBABILITY OF ISOLATED BACTERIA IN BRINGING ABOUT BIOMINERALISATION ON TITANIUM SURFACES Titanium surfaces were exposed into p Five sps of manganese oxidizng bacterial Cultures grown in nutrient medium amended with 50ppm of manganese

26 Pseudomonas spp. 14% of Mn Bacillus spp. 31% of Mn

27 Arthrobacter spp. 17% of Mn

28 INDUCTIVELY COUPLED PLASMA-ATOMIC EMMISION SPECTROMETRY (ICP-AES) INDUCTIVELY COUPLED PLASMA-MASS SPECTROMETRY (ICP-MS) REMOVAL OF Mn2+ FROM MEDIUM CONTAINING MOB ENRICHMENT OF Mn IN THE BIOFILM FORMED ON TITANIUM EXPOSED TO SEAWATER ANALYTICAL VALIDATION X-RAY PHOTOELECTRON SPECTROSCOPY (XPS) X-RAY DIFFRACTION STUDIES (XRD) PRESENCE OF MnOOH IN PRECIPITATE PRESENCE OF MnO2 IN THE PRECIPITATE

29 THE TITANIUM SURFACES WAS PRONE TO BIOFOULING 40-60%/ 80% OF BACTERIA IN BIOFILM ON Ti CAPABLE OF OXIDIZING Mn CONCLUSION AN UNEXPECTED NUMBER OF NON-CONVENTIONAL BACTERIA WERE ABLE TO OXIDIZE Mn POSSIBILITY OF BIOMINERALISATION ON TITANIUM SURFACES EXPOSED TO SEAWATER

30 SO WHAT????? CAUTION!!!! SURFACES CAN BECOME REFRACTORY TO MECHANICAL CLEANING DUE TO BIOMINERALISATION!!!! FUTURE FOCUS SURFACE MODIFICATION OF TITANIUM SURFACES TO IMPROVE THE ANTIBACTERIAL PROPERTIES WHICH CAN EFFECTIVELY SUPPLEMENT PRESENT TREATMENT PROGRAMMES