microbiological inspection of mineral water by redox-potential measurement

Microbiological inspection of mineral water by redox-

potential measurement

Dr Oliveacuter ReichartDr Katalin Szakmaacuter

Introduction

MicroTester as a validated method is suitable for rapid microbiological testing of mineral water carbonated water tank and running drinking water and other types of water The time needed for a reliable detection of microorganisms is of key importance in water industry the real-time (or at least as fast as possible) monitoring of the microbiological properties of the production is indispensable in public water supply the essential basis of the epidemiological and public health measures is the fast and reliable result of the microbiological inspection Beside the most important and most widely inspected microbiological contaminants the most relevant disturbing flora was involved to the validation process as well

Theoretical base

The energy source of the growth is the biological oxidation which results in a reduction in the environment

This is due to the oxygen depletion and the production of reducing compounds in the nutrient medium

A typical oxidation-reduction reaction in biological systems

[Oxidant] + [H+] + n e- [Reductant]

A typical redox curve of the microbial growth

DC Detection CriterionTTD Time to Detection

Microorganisms

The most frequently tested contaminant microorganisms in mineral water productions are

ColiformsEscherichia coliPseudomonas aeruginosaEnterococcus faecalisTotal count (22 degC and 37 degC)

Method validation

SelectivityLinearitySensitivityDetection limitRepeatability Robustness

Selectivity 1

Coliforms and Acinetobacter lwoffii in BBL(Ko Klebsiella oxytoca Ent Enterobacter aerogenes Citro

Citrobacter freundii Ec Escherichia coli Acin Acinetobacter

lwoffii)

Coliforms and Acinetobacter in BBL

-400

-200

0

200

400

600

0 5 10 15 20

t (h)

Eh

(m

V)

KolgN=355 Citro lgN=3 Ent lgN=348

Ec lgN=367 Acin lgN=365

Selectivity 2

Micrococcus and Enterococcus in Azid broth

Enterococcus and Micrococcus

0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)

Enterococcus Micrococcus

Selectivity 3

Growth in Cetrimide broth

0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)

Ps aeruginosa Ps fluoresc E coli Enterococcus

Pseudomonas aeruginosa Pseudomonas fluorescens E coli and Enterococcus faecalis in Cetrimid broth

LinearityThe linear relationship between the logarithm of the cell concentration and TTD values is demonstrated by the calibration curves From the concentrated suspensions of the test microorganisms tenfold dilution series were prepared in physiological salt solution From the members of the dilution series the redox-potential test flasks were inoculated with 10 ml suspension and the TTD values were determined

Linearity

Calibration curves of Coliforms

Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)

Citrobacter Klebsiella oxytoca Enterobacter E coli (37 degC)

Linearity

Calibration curve of E coli

Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity

Calibration curve of Enterococcus faecalis

Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity

Calibration curve of Pseudomonas aeruginosa

Pseudomonas aeruginosa Cetrimid

y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity Total count (37 degC)

y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Calibration curve of total count

Sensitivity

Microorganism Broth Regression equation Sensitivity

(minlog unit)

Citrobacter freundii BBL TTD (min) = 1190 - 132lgN

132

Klebsiella oxytoca BBL TTD (min) = 856 ndash 88lgN

88

Enterobacter aerogenes

BBL TTD (min) = 774 ndash 81lgN

81

Escherichia coli BBL TTD (min) = 596 ndash 68lgN

68

Pseudomonas aeruginosa

Cetrimid

TTD (min) = 1440 ndash 155lgN

155

Enterococcus faecalis Azid TTD (min) = 836 ndash 92lgN

92

The sensitivity of the measuring method was determined as the slope of the

calibration curves

Detection limit

The detection limit is 1 celltest flask so the system is suitable for the absencepresence tests so considerable costs and time could be saved with more membrane filters joined together

On the base of the calibration curves the range lasted from 1 to 7 log unit

Repeatability

The repeatability calculated from the calibration curves

SDlgN = 0092

SDN = 100092 = 124 = 24

which complies with the requirements of microbiological methods

Quality control tests 72 bottles tested for Coliform

Testing method of Laboratory Membrane filtering of 3x250 ml mineral

water with 1 filter Cultivation Tergitol agar at 37 degC for 48 h One Petri dish represents 3 bottles of mineral water

Redox-potential measurement method Membrane filtering of 3x250 ml mineral

water with 1 filter placing 4 membranes into 1 test flask containing BBL broth Temperature 37 degC One test flask represents 12 bottles of mineral water

Positive control 1 ml of Citrobacter freundii suspension (lgN = 366)

Quality control test

Results of redox-potential measurement of 72 bottles

72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48

49 - 60 61 - 72 Citrobacter


Bottles 1-12 13-24 25-36 37-48 49-60 61-72

Laboratory negative negative negative negative negative negative

Redox negative negative negative negative negative negative

Results of 72 bottles test

66 bottles tested for Coliforms

Testing method of Laboratory Membrane filtering of 3x250 ml mineral water

with 1 filter Cultivation Tergitol agar at 37 degC for 48 h One Petri dish represents 3 bottles of mineral water

Redox-potential measurement method Membrane filtering of 3x250 ml mineral water

with 1 filter placing 3 membranes into 1 test flask containing BBL broth Temperature 37 degC One test flask represents 9 bottles of mineral water

Besides the mineral water two technological water samples were tested for Coliforms

Positive control 1 ml of Escherichia coli suspension (lgN = 67)



66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ


Samples 1-66 Bottles Water sample 1 Water sample 2

Laboratory results negative negative negative

Redox method negative negative negative


Detection time of one cell

Microbe One cell detection time (h)

Escherichia coli 11Citrobacter freundii 23Pseudomonas aeruginosa 24Enterococcus faecalis15

Results of industrial tests

MicrobeAll

measurements (piece)

Match the

standard test ()

False positive results

()

False negative results

()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012

Advantages of the redox-potential measurement

Very simple measurement technique Rapid method especially in the case of

high contamination Applicable for every nutrient broth Especially suitable for the evaluation of

the membrane filter methods The test costs are less than those of the

classical methods especially in the case of zero tolerance (Coliforms Enterococcus Pseudomonas etc)

Microbiological inspection of mineral water by redox-potential

Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability

Quality control tests


Quality control test (2)







Introduction

MicroTester as a validated method is suitable for rapid microbiological testing of mineral water carbonated water tank and running drinking water and other types of water The time needed for a reliable detection of microorganisms is of key importance in water industry the real-time (or at least as fast as possible) monitoring of the microbiological properties of the production is indispensable in public water supply the essential basis of the epidemiological and public health measures is the fast and reliable result of the microbiological inspection Beside the most important and most widely inspected microbiological contaminants the most relevant disturbing flora was involved to the validation process as well

Theoretical base







Microorganisms



Method validation


Selectivity 1



lwoffii)


-400

-200

0

200

400

600

0 5 10 15 20

t (h)

Eh

(m

V)



Selectivity 2



0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)


Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Theoretical base







Microorganisms



Method validation


Selectivity 1



lwoffii)


-400

-200

0

200

400

600

0 5 10 15 20

t (h)

Eh

(m

V)



Selectivity 2



0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)


Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability












Microorganisms



Method validation


Selectivity 1



lwoffii)


-400

-200

0

200

400

600

0 5 10 15 20

t (h)

Eh

(m

V)



Selectivity 2



0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)


Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Method validation


Selectivity 1



lwoffii)


-400

-200

0

200

400

600

0 5 10 15 20

t (h)

Eh

(m

V)



Selectivity 2



0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)


Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Selectivity 1



lwoffii)


-400

-200

0

200

400

600

0 5 10 15 20

t (h)

Eh

(m

V)



Selectivity 2



0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)


Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Selectivity 2



0

50

100

150

200

250

300

350

400

0 5 10 15 20

t (h)

Eh (m

V)


Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Selectivity 3


0

100

200

300

400

500

0 5 10 15 20 25

t (min)

Eh

(m

V)




Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability











Linearity


Coliforms in BBL

y = -1699x + 17004

R2 = 09958y = -1471x + 1426

R2 = 09714

y = -13506x + 12896

R2 = 09941

y = -11775x + 10184

R2 = 099070

5

10

15

20

0 1 2 3 4 5 6 7

lgN (cfucell)

TT

D (

h)


Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Linearity


Escherichia coli

y = -08393x + 71607

R2 = 09988

0

2

4

6

8

0 1 2 3 4 5 6 7

logN100 ml

TT

D (

h)

Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Linearity


Enterococcus Azid

y = -15873x + 13222

R2 = 09859

0

5

10

15

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)

Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Linearity



y = -25536x + 23709

R2 = 09882

0

5

10

15

20

25

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability











y = -10135x + 87505

R2 = 09973

0

2

4

6

8

10

0 1 2 3 4 5 6 7 8

logN100ml

TT

D (

h)


Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Sensitivity


(minlog unit)


132


88



81


68


Cetrimid


155


92


calibration curves

Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Detection limit



Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










Repeatability


SDlgN = 0092

SDN = 100092 = 124 = 24










72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability


















72 bottles

-400

-300

-200

-100

0

100

200

300

400

500

600

0 2 4 6 8 10 12 14 16 18 20 22 24 26

t (h)

Eh

(m

V)

1 - 12 13 - 24 25 - 36 37 - 48



Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability











Bottles 1-12 13-24 25-36 37-48 49-60 61-72













66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability



















66 bottles

-400

-300

-200

-100

0

100

200

300

400

500

0 2 4 6 8 10 12 14 16 18 20 22 24

t (h)

Eh

(m

V)

1-9 10-18 19-27 28-36 37-45 46-5455-63 64-66 Ecoli (+) Negativ










MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability



















MicrobeAll


Match the

standard test ()


()


()

Escherichia coli

942 9989 011 000

Coliform 4674 9987 000 013

Enterococcus

3000 9993 000 007

Pseudomonas

aeruginosa3372 9982 006 012







Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability
















Introduction

Theoretical base


Microorganisms

Method validation

Selectivity 1

Selectivity 2

Selectivity 3

Linearity

Linearity (2)

Linearity (3)

Linearity (4)

Linearity (5)

Linearity (6)

Sensitivity

Detection limit

Repeatability










microbiological inspection of mineral water by redox-potential measurement

Technology

coli escherichia coli

public water

carbonated water

drinking water

water industry

types of water

mineral water productions

citro lgn