report biorec lab 1

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UNIVERSITI TEKNOLOGI MARA

FAKULTI KEJURUTERAAN KIMIABIOPROCESS ENGINEERING LABORATORY

(CBE 661)

No. Title Allocated Marks Marks1. Abstract/Summary 52. Introduction 5

3. Aims 54. Theory 55. Apparatus 56 Methodology/Procedure 107. Results 108. Calculations 109. Discussion 2010. Conclusion 1011. Recommendations 512. Reference 513. Appendices 5

TOTAL 100

Remarks:

Checked by: Rechecked by:

……………………………......... ……………………………..

Date: Date:

NAME AND MATRIC NO : MUHAMMAD ARSHAD BIN ABDUL RASHID

(2014683386)

GROUP : 5

EXPERIMENT : LAB 1 (GROWTH KINETICS STUDY OFMICROORGANISM)

DATE PERFORMED : 15 SEPTEMBER 2015

SEMESTER : 5

PROGRAMME CODE : EH242 5E

SUBMIT TO : PN SUHAILA BT MOHD SAUID



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Table of Contents

NO. TITLE PAGES

1 Abstract 3

2 Introduction 4

3 Objectives 5

4 Theory 5

5 Apparatus 8

6 Methodology/Procedure 8

7 Results 11

8 Calculations 17

9 Discussion 17

10 Conclusion 20

11 Recommendations 21

12 Reference 21

13 Appendices 22



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Abstract

In this experiment the study is for the growth kinetics of microorganisms in shake flask. E.coli is

grown in a LB and TB broth mediums and being fermented for 24 hours at 350 rpm and 370C.

Throughout the fermentation, the cell culture is taken out every 1 hours from 0 hour to 4 th hour

and continued with every 2 hour until 20th hour and the absorbance analysis, glucose analysis

and cell dry weight are being performed. As for the optical density analysis, the absorbance

reading from the spectrophotometer is taken while for the glucose test, the reading of glucose

level is taken from the YSI 2700 Select Biochemical Analyzer. These substrate concentration

values will then being plotted on graph with growth rate. The cell dry weight, in the other hand, is

taken after the mass concentration is being dried overnight in the oven. The weight of the tube

which contains the biomass before and after the drying process is recorded to get the cell dry

weight. For the optical density of the cell, the absorbance value showed an increment which

indicating that the cell was growing and number of cell is increased in the shake flask. The growth

rate, however, cannot be determined as the absorbance values were increased and decreased

unevenly and calculation of rate of microbial growth cannot be made as the data for cell dry weight

concentration, X are not consistent giving some of the results negative value thus some of the

rate of growth, μ and substrate constant, Ks cannot be calculated. Supposedly, as the number of

cell increased inside the shake flask, the cell dry weight also should be increased. Therefore no

conclusion can be made about the cell growth rate in the shake flask. Another reason because

the electronic weight balance shows different reading when weighted twice.



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Introduction

There are many ways to carried out Fermentation process such as batch, continuous and fed-

batch processes. In this experiment, we decided to use the shake flask fermentation. The shake

flask fermentation is an example of batch fermentation. In shake flask, the culture flask usually

Erlenmeyer flask is being used to place and growing the microorganisms. It is a small scale

equipment which equivalent to stirred tank bioreactor and it is also the cheapest and easiest way

to culture microorganism aerobically, in small volumes of nutrient broth.

To ensure the prevention of any contamination to the culture, shake flask must be plugged.

Different plug can be made of cotton-wool, glass wool, polyurethane foam, gauze or synthetic

fibrous material. In this experiment, we used cotton plugged. The plug function to prevent airborne

microorganism from getting into the medium while at the same time allowing free flow of air enter

the flask.

The cultures are incubated at certain temperature 37o C and shaking frequency 350 rpm for 4

hours in an incubator shaker to achieve a required growth rate. The shaking agitates the medium

and the culture to keep the mixture relatively homogeneous and also to ensure aeration, creating

an aerobic condition. In batch culture, it is closed environment that means there is neither input

supplied nor output generated throughout the fermentation. The medium culture is initially

inoculated with the microorganism. The growth keeps increasing until at certain extent, the growth

is inhibited because of the decreasing substrate concentration and the presence of toxic

metabolites.

The microorganism that we used to study in this experiment is E.coli . There are many specific

media for growth of E.coli but in this experiment we used Luria Bertani (LB) a Terrific Broth (TB)

media because it is the most commonly used medium in molecular biology for E. coli cell culture.

The relationship between the specific growth rate (μ) of a microbial population and the substrate

concentration (s), is an indispensable tool in all fields of microbiology, be it physiology, genetics,

ecology, or biotechnology, and therefore it is an important part of the basic teaching of

microbiology (Kovárová-Kovar. K, et. al, 1998)



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Objectives

– To study the growth kinetics of microorganism in shake flask experiment

– To construct a growth curve including lag, log, stationary and death phases

– To determine the Monod parameters

Theory

Shake flask fermentation is one of the examples of batch fermentation. Batch culture is an

example of a closed culture system which contains an initial, limited amount of nutrient. The

inoculated culture will pass through a number of phases. After an inoculation there is a period

during which no growth appears to take place. This period is referred as the lag phase and may

be considered as a time of adaptation. In a commercial process, the length of the lag phase should

be reduced as much as possible. Following a period during which the cell gradually increases,

the cell grows at constant, maximum rate and this period is known as the exponential phase. The

exponential phase may be described by the equation below:

= µx -------------------1

where

x is the concentration of microbial biomass

t is the time, in hours

µ is the specific growth rate, in hour -1

on integration, equation (1) gives

= ------------------2

where

is the original biomass concentration

is the biomass concentration after time interval, t hours

During the exponential phase, the organism is growing at its maximum specific growth rate,

µ for the prevailing conditions.



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Equation 2 predicts that growth will continue indefinitely. However, growth results in the

consumption of nutrients and the excretion of microbial products. Thus after a certain time the cell

growth rate will decrease until growth ceases. The cessation of growth may be due to the

depletion of some essential nutrient in the medium when there is limitation in substrate.

The decrease in growth rate and the cessation of growth due to the depletion of substrate may

be described by the relationship between µ and the residual growth-limiting substrate as follows:

µ =

+

where

µ = maximum growth rate

s = residual substrate concentration

= substrate utilization constant

Figure 4.1: The graph showing the relationship between the parameter of the Monod equation.

The stationary phase in batch culture is the point where the growth rate has declined to zero. In

the other word the growth rate is equivalent to the death rate. The cell death is might due to the

nutrient limitations due to their incorporation into cells during log-phase growth or a build-up of

toxins due to their release of fermentation products also during log-phase growth.



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The death phase is the result of the inability of the bacteria to carry out further reproduction as

condition in the medium become less and less supportive of cell division. The nutrient is extremely

insufficient for the growth of the microorganism. Eventually, the number of viable bacterial cells

begins to decline at an exponential rate. Industrial fermentation is usually interrupted at the end

of the exponential growth phase or before the death phase begins.

Figure 4.2: Growth curve of microorganism based on cell number analysis



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Apparatus

Microbe: Escherichia Coli

Shake flask (250mL flasks and 1000 mL flasks)

Eppendorf tubes / falcon tube (1.5 mL)

Cuvettes (spectrophotometer)

Incubator Shaker

Refrigerated Centrifuge

Media (for specific microbe)

Ethanol (70% ethanol for swabbing for sterility)

Spectrophotometer

Bunsen burner for sterility

Graduated Flask for measuring media (1000mL, 100mL, 10mL)

Laminar Flow hood for sterility

Biochemical Analyzer

HPLC for product measurement like ethanol

Cotton plugged

pH meter

Procedure

(i) Preparation of media

a) Terrific Broth (TB) preparation

1. The recipe as stated at the bottle is followed.

2. The media is autoclaved at 121 0C for 20 minutes

3. Glycerol and media has been autoclaved together.

4. pH reading should be near 7 as the media is a readied phosphate buffer solution

b) Luria Bertani (LB) preparation

1. The recipe as stated at the bottle is followed for LB media.

2. A certain amount of phosphate buffer is added to give a specific pH which is pH 7.

Refer to table below.



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3. Glucose solution is prepared and it should be autoclaved separately before cooled

down in a different bottle.

4. Distilled water is autoclaved which will be used for filling up volume to the needed

volume prepared.

5. When both solutions are cooled, then only both solutions are added.

Table 6.1: Buffer recipe according to 50 mM Buffer Strength

No Phosphate buffer

components

Concentration

1 K2HPO4 8 g/l

2 KH2PO4 3 g/l

(ii) Preparation of cell culture

a) Seed culture preparation (inoculum)

1. 5 loops of grown E coli is taken on agar plates and added to the sterilized media of

150mL in 1000mL shake flask. (you may need 2 of 1000mL shake flask to ensure

enough inoculum needed)

2. Sterility must be sustained during transfer.

3. The media is grown at 350 rpm for 4 hours and it is assumed as exponential growth of

E coli.

4. At this stage, the seed cultures are assumed to be at its most active condition.

5. OD reading is taken for seed culture using spectrophotometer during this time.

b) Main experiment

1. 10% of inoculum to the main experiment media is transferred using aseptic technique.

(For instance, if the working volume is 150ml, therefore, 10% of inoculum would be

15mL of seed culture needed).

2. The shake flask is then capped (cotton plugged) and swabbed with 70% ethanol before

incubation in a thermostated rotary shaker at required rotational speed and

temperature for 24 hours.



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(iii) Sampling

1. Required amount of sample is transferred into the sampling tube with interval time for

every hour or every 2 or 3 hours.

2. 5 mL of sample is withdrawn every time sampling is done during fermentation for

measuring optical density (OD), glucose analysis and total cell number (biomass

concentration: g/L).

3. Table below is referred for planned usage of sample volume:

Table 6.2: Sampling

No. Sample Name Volume (uL) Use for

1 OD 1000 Optical measurement using spectrophotometer

2 CDW 1000 For Cell Dry Weight measurement

3 S 1500 Glucose Analysis

iv) Absorbance Analysis (Optical Density) (OD)

1. 1 mL of sample is transferred into a cuvette and the optical density measurement is

made using a spectrophotometer with the wavelength set at 600nm.

2. The spectrophotometer is calibrated to zero by blank consisting 1 mL chosen media.

3. This method is used to measure cell growth; higher number of cells means more

absorbance, which is caused by low transmittance and vice versa.

v) Cell Dry Weight. (Biomass Concentration) (X) (g/L)

1. Dried centrifuge tubes is weighted and noted as initial mass.(empty container)

2. 1 mL sample is added to weighted centrifuge tube.

3. The sample is centrifuged at 10,000 rpm and at T of 4 oC. for 20 minutes

4. The supernatant is taken out and washing with distilled water and centrifuging may be

repeated

5. The centrifuge tube is dried(left with biomass only) in oven at 80 oC for overnight

6. The dried centrifuged tubes is left in desiccator for half an hour.

7. The centrifuge tube weighted and note this as final mass (with biomass = Cell Dry

Weight)

Cell Dry Weight = Final mass – Initial mass



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vi) Glucose Analysis. (Substrate Concentration) (S) (g/L)

1. Sample of 1.5 mL is transferred into the micro centrifuge tube and refrigerated centrifuged

for 10 minutes at 10,000 rpm.

2. Then, the supernatant is taken out into cuvette and put onto turntable of YSI 2700 Select

Biochemical Analyzer for direct analysis of glucose (dextrose) concentration.

3. The glucose analysis is based on Glucose Oxidase that has been immobilized in the YSI

Dextrose Membrane (YSI 2365).

Results

Luria Bertani Results

Seed Culture Preparation (Inoculum)

Initial OD : 1.278 (12.40pm)

Final OD : 2.532 (4.40pm)

Table 7.1: Shows The Data For Luria Bertani (LB)

No Time(h)

OD(nm)

M1

(g)M2

(g)X

(g/L)ln X(g/L)

(M2-M1)

S(g/L)

μ

(1/h)Ln (X/X0)

1 0 0.188 1.084 1.031 -26.5 - 8.71 - 0.000

2 1 0.189 1.076 1.085 4.5 1.504 8.82 - -

3 2 0.307 1.076 1.243 83.5 4.401 8.70 2.897 -

4 3 0.806 1.097 1.091 -3 - 7.92 - -2.179

5 4 0.853 1.103 1.095 -4 1.386 8.09 - -1.891

6 6 0.655 1.098 1.098 - - 5.79 - -

7 8 0.757 1.097 1.078 -9.5 - 5.72 - -1.026

8 10 0.783 1.093 1.093 - - 4.83 - -

9 12 0.802 1.098 1.109 5.5 1.705 4.21 -0.2695 -

10 14 0.282 1.104 1.155 25.5 3.239 3.89 0.767 -

11 16 0.406 1.089 1.091 1 0 3.47 -1.609 -

12 18 0.409 1.098 1.104 3 1.099 3.30 0.549 -

13 20 0.498 1.113 1.095 -9 - 2.90 - -1.080



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OD – Absorbance Optical DensityM1 – Empty CentrifugeM2 – Dried Centrifuge Tube + SampleX – Cell Dry Weight Concentration

S – Substrate

Figure 7.1: The growth curve of E.coli plotted using absorbance optical density.

Figure 7.2: Graph of ln X against time which is plotted to construct the growth curve of the cell

by using cell dry weight

0

0.2

0.4

0.6

0.8

1

0 5 10 15 20 25

Absorbance

(nm)

Time(h)

Graph of Absorbance (nm) against Time

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

0 5 10 15 20

ln X

Time (h)

ln X against Time



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By referring Figure 7.2, it show that the exponential phase may be between at 1th and 14th hour.

This is because at 1st to 2nd hour at 12th and 14th hour shows an increasing data. Thus, the data

between one of this period will be used to find the value µ max. I take period of 1st to 2nd hour.

Figure 7.3: Graph of ln X/X0 against time is plotted to find the value of µmax

From Figure 7.3, the value of µmax which is equal to the slope of the graph is 0.0554.

Thus, the doubling time is 12.51 h.

Figure 7.4: Graph of growth rate, μ against substrate concentration, S

y = 0.0554x - 2.0291

R² = 0.5576

-2.5

-2

-1.5

-1

-0.5

0

0 5 10 15 20 25

ln X/X0

Time (h)

ln X/Xo against Time

-2

-1.5

-1-0.5

0

0.5

1

1.5

2

2.5

3

3.5

0 1 2 3 4 5 6 7 8 9 10

μ

S

Graph Of Growth Rate Against Substrate Concentration



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From Figure 7.4 we cannot find the Ks we lack the value of μ thus make the graph uncomplete.

The value of Ks can be determined if the graph complete by using ½ μmax. By using Monod

Equation Ks value can be determined.

Terrific Broth Results

Seed culture preparation (inoculum)

Initial OD : 0.168

Final OD : 1.203

Table 7.2: Absorbance value at 600 nm obtained using Terrific Broth as medium

(fermentation)

No. Time (h) Absorbance Optical

Density (nm)

1 0 0.191

2 1 0.442

3 2 0.763

4 3 1.541

5 4 0.888

6 6 0.991

7 8 0.994

8 10 1.1109 12 1.103

10 14 1.129

11 16 1.526

12 18 1.178

13 20 1.068



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Figure 7.5: The growth curve of E.coli plotted using absorbance optical density.

Table 7.3: Results of Cell Dry Weight (CDW) obtained using Terrific Broth as medium

No. Time

(h)

Empty

tube +

sticker (g),

m1

Empty tube +

sticker + cell

(g), m2

Cell dry

weight (g)

(m2 – m1)

Cell mass

concentration,

X (g/L)

ln x ln X/X0

1 0 1.10991 1.10 0.0009 0.45 -0.7985 0.000

2 1 1.1030 1.11 0.0070 3.50 1.2528 2.0513

3 2 1.0946 1.09 -0.0046 2.30 0.8329 1.6314

4 3 1.0861 1.09 0.0039 1.95 0.6678 1.4663

5 4 1.1064 1.11 0.0036 1.80 0.5878 1.3863

6 6 1.1021 1.11 0.0079 3.95 1.3737 2.1722

7 8 1.0983 1.11 0.0117 5.85 1.7664 2.5649

8 10 1.1032 1.11 0.0068 3.40 1.2238 2.0223

9 12 1.1106 1.13 0.0194 9.70 2.2721 3.0707

10 14 1.1005 1.11 0.0095 4.75 1.5581 2.3567

11 16 1.0920 1.10 0.0080 4.00 1.3863 2.1848

12 18 1.1029 1.11 0.0071 3.55 1.2669 2.0655

13 20 1.1025 1.11 0.0075 3.75 1.3218 2.1203

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 5 10 15 20 25

Absorbance

(nm)

Time(h)

Graph of Absorbance (nm) against Time



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Figure 7.6: Graph of ln X against time which is plotted to construct the growth curve of the cell

by using cell dry weight

By referring Figure 7.6, it show that the exponential phase may at between at 4th and 12th hour.

Thus, the data between that particular times will be used to find the value µmax.

Figure 7.7: Graph of ln X/X0 against time is plotted to find the value of µmax

From Figure 7.7, the value of µmax which is equal to the slope of the graph is 0.1997.

Thus, the doubling time is 3.4709.

0

0.5

1

1.5

2

2.5

0 5 10 15 20 25

ln X

Time (h)

ln X against Time

y = 0.1997x + 0.8006

R² = 0.9213

0

0.5

1

1.5

2

2.5

3

3.5

0 5 10 15

ln X/X0

Time (h)

ln X/Xo against Time

Y-Values

Linear (Y-Values)



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Calculations

Cell dry weight, X

X = final weight – initial weightVolume of Sample

= 1.085 g – 1.076 g

= 0.009 g

Growth Rate, μ

μ = ln x1 – ln x0

Time1 – Time0

= ln 83.5 – ln 4.52 – 1

= 2.897 1/h

Yield of substrate, (Y

)

Y

= -

∆

∆ (g cells/ g substrate)

- 25.5 – 5.5 = 62.5 g cells/ g substrate3.89 – 4.21

Saturation constant (Ks)

μg = μmax . SKs +S

No example due to results error

Discussion

Microorganism population growth studies require inoculation of viable cells into a sterile broth

medium and incubation of the culture under optimum temperature, pH, and gaseous conditions.

This experiment is carried out to study the kinetic growth of microorganism. E.coli is selected as

the cell and being cultivated inside a shake flask. We used the growth of microorganism in shake

flask which is a simple method of fermentation. The nutrients for the microorganism are being

supplied by the media which contain the carbon sources. In this experiment we used Luria Bertani

(LB) and Terrific Broth (TB) as media. The flask is shaken during the cultivation to ensure constant

mixing of the cell and the media therefore increase the homogeneity between these two and also

to provide aeration for the cells. The culture is gone through the fermentation process for 20 hours.



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Within that period, the biomass/cell sample is taken out for every 1 hours from 0 hour to 4 hour

and continued every 2 hour from 4 hour to 20 hour. This is done to analyze the concentration of

the cell (g/L), the cell dry weight and the glucose concentration.

In order to analyze the concentration of the cell inside the flask, absorbance reading for the optical

density is taken from the spectrophotometer. The higher the absorbance reading means higher

number of cell presence inside the flask at a particular time. As for this experiment, the

absorbance reading for LB is increase from the beginning of the experiment until the 6th hour and

decrease slightly until the 8th hour then increase back before decrease until 20 th hour. It can be

explained that the number of cell increase and decrease inconsistently throughout the cultivation.

In the other hand, the decrease in cell number in 6th and 14th hour indicating that the cell growth

has been interrupted maybe because there are contamination occur to the sample. The

absorbance reading for TB shows increasing until 10th hour then it decrease a bit before increase

until 18th hour. For TB media, the results shows better reading maybe there are no contamination

occur during conducting the experiment. When there is other microorganism in the culture, the

growth will be interrupted thus the growth of E. coli started to slow down. When there are different

microorganism during the growth they will compete each other to keep living. Only the strong

microorganism can withstand starvation. There is much turnover of protein for the culture to cope

with this period of low substrate availability. In cell growth, the cell will go through several phases

like lag, exponential, deceleration, stationary and death phase. We can say the absorbance

experiment is fail due to inconsistence result.

In cell cultivation, the cells themselves need food or carbon sources like glucose for growth. In

batch fermentation for example in this experiment, the glucose can be the limiting factor for the

cell growth or we called it as substrate limiting growth. For this condition, the Monod equation can

be used to predict the growth rate and the cell concentration inside the shake flask. In addition,

the glucose concentration can be known by testing the cell sample into the glucose analyzer and

the direct glucose concentration can be obtained. The LB media experiment, there are glucose

concentration in there and the reading was obtained by using glucose analyzer. From the results

of substrate concentration, we manage to get what we suppose to get which is the reading will

decrease against time. Although the starting reading is lower than the second reading, the third

until the last reading shows decreasing.



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For the graph ln X against time, we also fail to get the estimated result. This graph is plotted to

determine the gradient of exponential phase which is the μmax. The estimated exponential phase

for LB media is from 1st hour until 14th hour. The graph shows decreasing at 2nd hour might be

because of contamination. The reason why I estimate the exponential growth until 14 th hour

because the growth occur until that hour. The µmax for this period is 0.0554. For TB media, the

estimated exponential phase may at between at 4th and 12th hour thus, the data between that

particular times will be used to find the value µmax which is 0.1997. The graph below shows the

result that we should achieved but we fail due to so many error.

Figure 9.1: Graph the number of cell against time

Another analysis that can be performed to analyze the cell sample is by taking the dry weight of

the cell. In this method, the cell is being taken out from cultivation flask and transferred into

centrifuged tube. Before that, the empty centrifuged tube is weighted. Then the tube is the being

centrifuged to separate the supernatant with the cell. For LB media, the supernatant is separate

and will be used for glucose analysis but for TB media, the supernatant is separated and removed.

The remained cell is washed with distilled water and centrifuged again before being dried inside

an oven for 24 hours. The dry cell weight with tube is finally taken and the result will be subtract

with the weight of initial empty tube to know the weight of the cell that present at particular time

during the cultivation. In this experiment, the cell dry weight should increased from 0 th hour until

the 20th hour. Unfortunately, we did not manage to get like that because the electronic weight

balance is not accurate. We weight each tube for two times but still get different reading. The

worst part comes when the final reading of cell dry weight with tube is smaller than the initial

reading of empty tube. This will give negative reading thus it is impossible for us to produce a

good graph. When we get negative reading for cell dry weight, we cannot calculate the growth

rate and this happen for LB media.



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Conclusion

After conducting the experiment we can ensure that, E.coli is suitable to be fermented inside a

shake flask and it is a simple method to investigate the growth kinetics of the microorganism.

Knowledge of microbial growth kinetics is essential to determine when to harvest the culture for

different purposes. Although we fail to achieve the objectives due to some errors during

conducting the experiment, we try to learn our mistake for next experiment.

Microorganism will go through several phases in their growth, several analyses on the cell

need to be done to know the growth kinetics of the cell and the duration for each phase. This

includes the cell concentration, glucose concentration and also the cell dry weight analyses. This

method can be done in the laboratory before the fermentation or the cultivation of microbes in

large scale is performed. Growth kinetics deals with the rate of cell growth and how it is affected

by various chemical and physical conditions. During the course of growth, the cells is continuously

changing and adapting itself in the media environment, which is also continuously changing in

physical and chemical conditions.

In conclusion, the microbial culture in batch culture system that is shake flask system goes

through a lag phase, exponential growth phase, decelerating growth phase, stationary phase and

sometimes the death phase depends on the end product desired. The substrate concentration in

the culture medium and growth parameters, such as glucose concentration changes

correspondingly throughout the growth phases. Thus, the physiology of the microorganisms is

always in a transient stage, subjected to a continually changing culture conditions. Consequently,

product formation is confined to a certain period of cultivation, for example antibiotics would only

be produced in the decelerating and stationary growth phases.

The batch culture system is still widely used in certain industrial processes for example

brewery industry because of its easy management of feed stocks. These advantages allow the

use of unskilled labor and low risk of financial loss. Low level of microbial contamination in

fermented products is at time tolerable, as long as the microbial contaminants are not pathogenic

and do not alter the desired properties of the product, such as taste, color and texture.



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Recommendation

– Aseptic technique must be practised when handling biomass concentration to avoid any

contamination.

– Cuvette must be wiped cleanly to prevent any scratch that would affect the

spectrophotometer reading during protein test.

– Disinfect the work area with 70% alcohol before handling the culture.

– Dispose of all contaminated materials in appropriate containers.

– The cap of the viral must be opened to fasten the drying process of the biomass in the

oven.

– The supernatant of cell concentration should be taken out carefully without any taking out

of the biomass.

– This experiment must be carried out under the laminar flow to prevent any contamination

to the culture.

– Wash hand after handling the culture.

References

Ardestani, F., (2011). Investigation of the Nutrient Uptake and Cell Growth Kinetics with Monod

and Moser Models for Penicillium brevicompactum ATCC 16024 in Batch Bioreactor.culture, Iranica Journal of Energy and Environment (IJEE), 2(2): 117-121

Crueger W and Crueger A., (1990). Biotechnology: A Textbook of Industrial Microbiology . Sinauer

Associates, Sunderland Massachusetts.

Kovárová-Kovar, K., & Egli, T. (1998). Growth Kinetics of Suspended Microbial Cells: From

Single-Substrate-Controlled Growth to Mixed-Substrate Kinetics. Retrieved on October 4,

2015 from http://mmbr.asm.org/content/62/3/646.full

PF Stanbury and A Whitaker.,1984. Principles Of Fermentation Technology . Pergamon Press

http://mmbr.asm.org/content/62/3/646.full

http://mmbr.asm.org/content/62/3/646.full



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Appendix

Figure 13.1: Result of the experiment after being Figure 13.2: After being heated, the sampleapproved is being cooled inside a desiccator.

Figure 13.3: Glucose analysis machine model Figure 13.4: Incubator ShakerYSI 2700

report biorec lab 1

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