The Effects of Epsom Salt on Microorganisms Isolated From Sewage Isitua Chinwe Christy1,*, Ibeh Isaiah Nnanna2 and Ajuzie Christopher Uche3

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38
The Journal of Applied Sciences Research.1(1):38-42. 2014
The Journal of Applied Sciences Research
Journal homepage: http://www.journals.wsrpublishing.com/index.php/jasr
Print ISSN: 2345-4377 Online ISSN: 2383-2215
Original Article
The Effects of Epsom Salt on Microorganisms Isolated From Sewage
Isitua Chinwe Christy1,*, Ibeh Isaiah Nnanna2and Ajuzie Christopher Uche3
1Department of Biological Science, Microbiology Unit, College of Sciences, AfeBabalola University, P.M.B. 5454, Ado-Ekiti, Ekiti
State, Nigeria
2Department of Medical Laboratory Science, College of Medical Sciences, University of Benin, P.M.B. 1154, Benin City, Edo State,
Nigeria
3Department of Microbiology, College of Natural and Applied Sciences, Achievers University, Owo, Ondo State, Nigeria
ARTICLE INFO
ABSTRACT
Corresponding Author:
Isitua Chinwe Christy
christykings@yahoo.com
The occurrence and distribution of pathogenic and non-pathogenic
microorganisms in sewage maybe a public health concern with regards to
disposal. Various sewage treatment methods exist but this study investigates the
effectiveness of Epsom salt on sewage microorganisms. Serially diluted
samples of sewage were surface plated on nutrient agar and potato dextrose
agar for isolation of bacteria and fungi present. Four genera of bacteria;
Staphylococcus aureus,Escherichia coli, Klebsiellapneumoniae,
Psuedomonasaeruginosa and four genera of fungi; Aspergillusniger,
Aspergillusflavus,Penicillium spp., and Saccharomyces cerevisiae were
isolated. The susceptibility of these isolates to Epsom salt was determined
using the agar diffusion method. Klebsiellapneumoniae and Staphylococcus
aureus were highly sensitive to Epsom salt while the fungal isolates were
unaffected suggesting that the salt has no antifungal effects.
Keywords: Epsom salt, Sewage, Sewage treatment, Susceptibility.
How to cite this article:
Christy, I.C., I.I. Nnanna and
A.C. Uche. 2014. The Effects
of Epsom Salt on
Microorganisms Isolated
From Sewage. The Journal of
Applied Sciences Research.
1(1): 38-42.
Article History:
Received: 20 September 2014
Accepted: 5 October 2014
Copyright © 2014, World Science and Research Publishing. All rights reserved.
INTRODUCTION
The origin, composition and quantity of wastes are related to existing life patterns. When
waste matter enters water, the resulting product is called sewage or waste water. Sewage is
any liquid that has been severely or adversely affected in quality by anthropogenic influence
(Tchobanoglous and Dowes, 2003). Sewage is correctly the subset of waste water that is
contaminated with faeces or urine but is often used to mean any waste water. It can also be
the liquid from toilets, baths, shower, kitchen, sinks e.t.c., disposed via sewers and some
surface water from roof tops or hard standing areas (Kadam et al., 2008).
The organic matter in a typical domestic sewage is approximately 50% carbohydrate, 40%
protein and 10% fat. The pH range is from 6.5 to 8.0 (Karadi and Huang, 2008). The
composition of sewage varies widely and it includes; water (> 90 %) which is often added
during washing away or flushing to carry waste (liquid or solid) down a drain (Okoh et al.,
38
The Journal of Applied Sciences Research.1(1):38-42. 2014
The Journal of Applied Sciences Research
Journal homepage: http://www.journals.wsrpublishing.com/index.php/jasr
Print ISSN: 2345-4377 Online ISSN: 2383-2215
Original Article
The Effects of Epsom Salt on Microorganisms Isolated From Sewage
Isitua Chinwe Christy1,*, Ibeh Isaiah Nnanna2and Ajuzie Christopher Uche3
1Department of Biological Science, Microbiology Unit, College of Sciences, AfeBabalola University, P.M.B. 5454, Ado-Ekiti, Ekiti
State, Nigeria
2Department of Medical Laboratory Science, College of Medical Sciences, University of Benin, P.M.B. 1154, Benin City, Edo State,
Nigeria
3Department of Microbiology, College of Natural and Applied Sciences, Achievers University, Owo, Ondo State, Nigeria
ARTICLE INFO
ABSTRACT
Corresponding Author:
Isitua Chinwe Christy
christykings@yahoo.com
The occurrence and distribution of pathogenic and non-pathogenic
microorganisms in sewage maybe a public health concern with regards to
disposal. Various sewage treatment methods exist but this study investigates the
effectiveness of Epsom salt on sewage microorganisms. Serially diluted
samples of sewage were surface plated on nutrient agar and potato dextrose
agar for isolation of bacteria and fungi present. Four genera of bacteria;
Staphylococcus aureus,Escherichia coli, Klebsiellapneumoniae,
Psuedomonasaeruginosa and four genera of fungi; Aspergillusniger,
Aspergillusflavus,Penicillium spp., and Saccharomyces cerevisiae were
isolated. The susceptibility of these isolates to Epsom salt was determined
using the agar diffusion method. Klebsiellapneumoniae and Staphylococcus
aureus were highly sensitive to Epsom salt while the fungal isolates were
unaffected suggesting that the salt has no antifungal effects.
Keywords: Epsom salt, Sewage, Sewage treatment, Susceptibility.
How to cite this article:
Christy, I.C., I.I. Nnanna and
A.C. Uche. 2014. The Effects
of Epsom Salt on
Microorganisms Isolated
From Sewage. The Journal of
Applied Sciences Research.
1(1): 38-42.
Article History:
Received: 20 September 2014
Accepted: 5 October 2014
Copyright © 2014, World Science and Research Publishing. All rights reserved.
INTRODUCTION
The origin, composition and quantity of wastes are related to existing life patterns. When
waste matter enters water, the resulting product is called sewage or waste water. Sewage is
any liquid that has been severely or adversely affected in quality by anthropogenic influence
(Tchobanoglous and Dowes, 2003). Sewage is correctly the subset of waste water that is
contaminated with faeces or urine but is often used to mean any waste water. It can also be
the liquid from toilets, baths, shower, kitchen, sinks e.t.c., disposed via sewers and some
surface water from roof tops or hard standing areas (Kadam et al., 2008).
The organic matter in a typical domestic sewage is approximately 50% carbohydrate, 40%
protein and 10% fat. The pH range is from 6.5 to 8.0 (Karadi and Huang, 2008). The
composition of sewage varies widely and it includes; water (> 90 %) which is often added
during washing away or flushing to carry waste (liquid or solid) down a drain (Okoh et al.,
38
The Journal of Applied Sciences Research.1(1):38-42. 2014
Original Article
The Effects of Epsom Salt on Microorganisms Isolated From Sewage
Isitua Chinwe Christy1,*, Ibeh Isaiah Nnanna2and Ajuzie Christopher Uche3
1Department of Biological Science, Microbiology Unit, College of Sciences, AfeBabalola University, P.M.B. 5454, Ado-Ekiti, Ekiti
State, Nigeria
2Department of Medical Laboratory Science, College of Medical Sciences, University of Benin, P.M.B. 1154, Benin City, Edo State,
Nigeria
3Department of Microbiology, College of Natural and Applied Sciences, Achievers University, Owo, Ondo State, Nigeria
ARTICLE INFO
ABSTRACT
Corresponding Author:
Isitua Chinwe Christy
christykings@yahoo.com
The occurrence and distribution of pathogenic and non-pathogenic
microorganisms in sewage maybe a public health concern with regards to
disposal. Various sewage treatment methods exist but this study investigates the
effectiveness of Epsom salt on sewage microorganisms. Serially diluted
samples of sewage were surface plated on nutrient agar and potato dextrose
agar for isolation of bacteria and fungi present. Four genera of bacteria;
Staphylococcus aureus,Escherichia coli, Klebsiellapneumoniae,
Psuedomonasaeruginosa and four genera of fungi; Aspergillusniger,
Aspergillusflavus,Penicillium spp., and Saccharomyces cerevisiae were
isolated. The susceptibility of these isolates to Epsom salt was determined
using the agar diffusion method. Klebsiellapneumoniae and Staphylococcus
aureus were highly sensitive to Epsom salt while the fungal isolates were
unaffected suggesting that the salt has no antifungal effects.
Keywords: Epsom salt, Sewage, Sewage treatment, Susceptibility.
How to cite this article:
Christy, I.C., I.I. Nnanna and
A.C. Uche. 2014. The Effects
of Epsom Salt on
Microorganisms Isolated
From Sewage. The Journal of
Applied Sciences Research.
1(1): 38-42.
Article History:
Received: 20 September 2014
Accepted: 5 October 2014
Copyright © 2014, World Science and Research Publishing. All rights reserved.
INTRODUCTION
The origin, composition and quantity of wastes are related to existing life patterns. When
waste matter enters water, the resulting product is called sewage or waste water. Sewage is
any liquid that has been severely or adversely affected in quality by anthropogenic influence
(Tchobanoglous and Dowes, 2003). Sewage is correctly the subset of waste water that is
contaminated with faeces or urine but is often used to mean any waste water. It can also be
the liquid from toilets, baths, shower, kitchen, sinks e.t.c., disposed via sewers and some
surface water from roof tops or hard standing areas (Kadam et al., 2008).
The organic matter in a typical domestic sewage is approximately 50% carbohydrate, 40%
protein and 10% fat. The pH range is from 6.5 to 8.0 (Karadi and Huang, 2008). The
composition of sewage varies widely and it includes; water (> 90 %) which is often added
during washing away or flushing to carry waste (liquid or solid) down a drain (Okoh et al.,
Isitua Chinwe Christy et al.,The Journal of Applied Sciences Research. 1(1): 38-42. 2014
39
2007). Non- pathogenic (> 100,000/ ml for sewage) and pathogenic microorganisms such as
bacteria, viruses, fungi, prions and parasitic worms are also present (Stensel et al., 2003).
Harmful organic and inorganic compounds and pathogenic microbes in sewage can
contaminate water causing water related diseases transmitted through fecal-oral route. These
health problems include; bacillary dysentery, cholera, typhoid fever and acute gastrointestinal
tract illness amongst others (Straub and Chandle, 2003; Hamner et al., 2006; Oliver, 2010).
Epsom salt is the common name for a colorless or white crystalline salt magnesium
sulphate hepta-hydrate, (MgSO4.7H2O) found in the minerals kieserite and epsomite,
occurring dissolved in sea water and in most mineral waters. It was discovered in 1618 and it
was first prepared at Epsom, England, where it got its name from. There it was distilled and
marketed primarily as a bath salt (Milton et al., 1999). The salt has a bitter taste, prepared
from hydrated magnesium sulphate and formed by reacting magnesium salt and sodium
hydroxide. The knowledge of it and its many uses have been with us since the 1500s.
In medicine, Epsom salt is used in treating patients with various illnesses ranging from
cardiac arrest, respiratory congestion, fibromyalgia and osteoporosis. It is administered to
delay or prolong the labor in women who are experiencing it prematurely; it flushes out toxins
in the body that are brought about by stress and relaxes the muscles and soothes away pain
(Arkin, 2008). Epsom salt is used in beauty treatments, soaps and detergents, food industry,
pharmaceutical industry, agricultural industry and as an emulsion breaker in sewage
clarification (Stentor, 2001).
This study therefore aims at determining the effects of Epsom salton microorganisms
isolated from sewage with a view to ascertain its usage as a tool for sewage treatment before
dispersal.
METHODOLOGY
Collection of Sample
Crude sewage samples were collected from two locations (Hostel I and Hostel II and
labeled Sample A and Sample B respectively) in sterile containers at female hostels of a
Nigerian University. These samples were immediately taken to the laboratory for microbial
analysis.
Microscopy and Culture of Sample
1.0 ml of the stock solution of sewage sample A and B were serially diluted for up to 10-5
and 1.0 ml of the dilution samples was inoculated separately in duplicate plates of nutrient
agar and potato dextrose agar using the pour plate method. All media were prepared according
to manufacturer’s instruction. The nutrient agar plates were incubated at 37oC for 24 H while
the potato dextrose agar plates were incubated at room temperature (28 ± 2oC) for 5 7 days.
Pure isolates of resulting growths were identified using the Bergey’s Manual of Determinative
Bacteriology (Holt et al., 1994) and Cowan and Steel’s Manual for the identification of
Medical bacteria (Barrow and Feltham, 1999).
The fungal isolates were examined macroscopically and microscopically following staining
with lactophenol cotton blue wet mount technique (Cheesbrough 2006).
Test Organisms
The isolated bacteria and fungi from the sewage samples were used as test organisms. The
isolates include: Staphylococcus aureus, Escherichia coli, Klebsiellapneumoniae and
Pseudomonas aeruginosa for bacteria; while Aspergillusniger, Aspergillusflavus, Penicillium
spp. and Saccharomyces cerevisiae for fungi. Pure cultures of these test organisms were used
to determine the mean zones of inhibition of the Epsom salt used.
Isitua Chinwe Christy et al.,The Journal of Applied Sciences Research. 1(1): 38-42. 2014
40
Determination of the Antimicrobial Activity of Epsom salt
The antimicrobial activity of Epsom salt was determined using agar well diffusion method
(Cheesbrough, 2006). Following dilution in sterile distilled water, different concentrations of
the Epsom salt solution were obtained as; 25 g/ml, 8.3 g/ml, 5 g/ml and 2 g/ml with sterile
distilled water used as control.
In-vitro Demonstration of Antimicrobial Activity (Sensitivity Test)
After solidification of nutrient agar and potato dextrose agar, 1.0 ml of the different
isolates already prepared in accordance to MacFarland standard were seeded evenly unto the
surface of the nutrient agar and potato dextrose agar plates and a sterile glass spreader was
used for even distribution of the in ocula. Holes or wells were drilled in the agar using a
sterile cork borer of 6mm diameter and 1.0 ml of the Epsom salt solution at the different
concentrations was introduced into the separate wells, with the central well containing sterile
water, which served as the control. The Epsom salt solutions were allowed to diffuse into the
medium and then incubated aerobically for 48 H at 37oC for bacteria and at 28 ± 2oC for
fungi. The plates were examined for zones of inhibition which indicated the degree of
susceptibility of the isolates. The minimum inhibitory concentration (MIC) defined as the
lowest concentration that completely inhibited the growth showing a clear zone was also
determined (Thongson et al., 2004).
RESULTS AND DISCUSSION
From the investigation on the effects of Epsom salt on microorganisms isolated from sewage,
the following results were obtained:
The mean population counts of bacteria and fungi isolated from the sewage samples A and B
were 6.20×104and 7.50×104respectively for bacteria and 1.15×104and 4.85×104respectively
for fungi (Table 1). This finding shows that the sewage samples contain a higher total viable
count of bacteria than fungi. Sewage samples from Hostel II had a higher total viable count
for both bacteria and fungi than that from Hostel I (Sewage sample A).
Table 1: Mean population counts of bacteria and fungi isolated from the sewage samples
Sewage Samples
Bacteria Count×104 (CFU / ml)
Fungal Count×104 (CFU / ml)
Hostel I (A)
6.20
1.15
Hostel II (B)
7.50
4.85
A total of eight (08) distinct microorganisms were isolated from the both sewage samples.
Four (04) of the microbial isolates were bacteria while the other four (04) were fungi (Table
2).
Table 2: Microorganisms isolated from the sewage samples
Bacteria
Fungi
Staphylococcus aureus
Aspergillusniger
Klebsiellapneumoniae
Aspergillusflavus
Psuedomonasaeruginosa
Penicillium spp.
Escherichia coli
Saccharomyces cerevisiae
The Epsom salt solutions showed antibacterial activity with respect to the different
concentrations used (Table 3). At concentrations of 25 g/ ml, 8.3 g/ml and 5 g/ml all the
bacterial isolates showed clear zones of inhibition to the Epsom salt solution used. At the least
concentration of 2 g/ml, only Klebsiellapneumoniae showed a clear zone of inhibition with
8.00 mm in diameter.K. pneumoniae and S. aureus were highly sensitive to the Epsom salt
solution used.
Isitua Chinwe Christy et al.,The Journal of Applied Sciences Research. 1(1): 38-42. 2014
41
The effect of Epsom salt were felt on the bacterial isolates at different concentrations but
the fungal isolates showed no zone of inhibition to Epsom salt. The reason why the fungal
isolates showed no sensitivity to the different concentrations of Epsom salt could be that the
sewage fungi possessed some resistant structures in the form of spores, with which they used
to withstand adverse conditions, in this case, as it has to do with the action of the Epsom salt
on the biosynthesis of their cell wall components (Zhang et al., 2003).
Table 3: In vitro antimicrobial activity of different concentrations of
Epsom salt solution using agar well diffusion method
Test Organisms
25 g/ml
Epsom Salt
8.3 g/ml
Solution 5
g/ml
2 g/ml
Distilled
water
(Control)
Bacteria
mm
Mm
mm
mm
mm
Staphylococcusaureus
13.00
12.00
11.00
0.00
0.00
Klebsiellapneumoniaes
13.20
11.60
0.40
8.00
0.00
Pseudomonasaeruginosa
11.00
10.00
9.00
0.00
0.00
Escherichiacoli
11.20
10.00
8.00
0.00
0.00
Fungi
Aspergillus niger
0.00
0.00
0.00
0.00
0.00
Aspergillus flavus
0.00
0.00
0.00
0.00
0.00
Penicillium spp.
0.00
0.00
0.00
0.00
0.00
Saccharomycescerevisiae
0.00
0.00
0.00
0.00
0.00
*Values are mean zones of inhibition (mm diameter)
CONCLUSION AND RECOMMENDATION
Epsom salt is widely applied in general usage and as an emulsion breaker in sewage
clarification. Thus, the results of this study have provided scientific justification for the use of
Epsom salt in the inhibition of sewage microorganisms which constitutes health hazards if not
properly treated or disposed. Therefore, the use of Epsom salt as an inhibitor of
microorganisms especially bacteria, should be encouraged.
REFERENCE
Arkin, J.C. 2008. About Epsom salt and Epsom salt
for healthy living. Reference and Education:
Science, Health and Fitness Article.
Barrow, G.I., and R.K.A. Feltham. 1999. Cowan
and Steel’s Manual for the Identification of
Medical Bacteria .3rd Edition. Cambridge
University Press. 331p.
Cheesbrough, M. 2006. District Laboratory
Practice in Tropical Countries Part 2. 2nd
Edition, Cambridge University Press. pp: 1-
267.
Hamner, S. A., R.K. Tripath, N. Miohr, S.C.
Bouskill, B.H. Broadway, and T.E. Ford.
2006. The role of water use patterns and
sewage pollution in incidence of water-
borne/enteric diseases along the Ganges in
Varanasi India. International Journal of
Environmental Health Research. 16 (2): 113-
132.
Holt, J.G., N.R. Krieg, P.H.A. Smeath, J.T.
Stanley, and S.T. Williams. 1994. Bergey’s
Manual of Determinative Bacteriology. 9th
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Baltimore, 783p.
Kadam, A., G. Ozaa, P. Nemaden, S. Duttaa, and
H. Shanka. 2008. Municipal wastewater
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Karadi, G.M. and J.Y.C. Huang. 2008. Sewage
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Milton, E., A.W. Skogstad, and F. Corazza. 1999.
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Okoh, A.I., E.E. Odjadjare, E.O. Igbinosa, and
A.N. Osode. 2007. Wastewater treatment
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Stensel, M.E., W. Edward, and B.H. Andersen.
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Stentor, I. 2001. Pontiac fever at a sewage
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Tchobanoglous, H.D. and J.M. Douwes. 2003.
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