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BIOCHEMICAL CHARACTERIZATION AND ANTIBACTERIAL PROPERTIES OF FISH SKIN
MUCUS OF FRESH WATER FISH, HYPOPHTHALMICHTHYS NOBILIS
Original Article
ANIL K. TYOR, SUNIL KUMARI
Fish and Fisheries Laboratory, Department of Zoology, Kurukshetra University, Kurukshetra 136119
Email: akumar@kuk.ac.in
Received: 05 Feb 2016 Revised and Accepted: 20 Apr 2016
ABSTRACT
Objective: The present study was undertaken to characterize the biochemical composition and antibacterial activity of skin mucus of fish
Hypophthalmichthys nobilis against different human and fish pathogenic bacterial strains viz. Klebsiella pneumonia, Pseudomonas aeruginosa,
Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, Bacillus cereus and Aeromonas hydrophilla.
Methods: Skin mucus of fish H. nobilis was collected by skin scarping method. Antibacterial activity of mucus extract was carried out by agar well
diffusion method and measured in terms of zone of inhibition(ZOI) in mm. Antibacterial activity of mucus extract was then compared with two
antibiotic amikacin and chloramphenicol. Minimum inhibitory concentration (MIC) of skin mucus extract was also determined.
Results: The biochemical characterization of epidermal mucus extract revealed the presence of proteins as a major component (265±2.64 µg/ml)
followed by carbohydrate content (63.66±0.88 µg/ml) and lipid content (0.0077±0.66 g/ml) respectively. Remarkable antimicrobial activity against
all the selected microbial strains was observed. Zone of inhibition (ZOI) shown by crude mucus extract against all the bacterial strains was found to
be significantly higher than higher than Chloramphenicol.
Conclusion: The present study opined that skin mucus of this fish can be used as potential antimicrobial components.
Keywords: Hypophthalmichthys nobilis, Microorganism, Fish skin mucus, Antibacterial activity, ZOI, MIC
© 2016 The Authors. P ublished by Innovare Academic Scie nces Pvt Ltd. This is an o pen access articl e under the CC BY licens e (http://creativecommons.org/licenses/by/4.0/)
INTRODUCTION
The worldwide emergence of E. coli, K. pneumonia, Haemophilus sp.,
S. aureus and many other ß-lactamase producers have become a
major therapeutic problem. Hospitals worldwide have become
literal breeding grounds for some of the most deadly bacteria. It is
now estimated that half of S. aureus strains found at many medical
institutions are resistant to antibiotics such as Methicillin [1].
Indiscriminate use of antibiotics has become the major factor for the
emergence and dissemination of multi-drug resistant strains of
several groups of microorganisms [2]. Even though pharmacological
industries have produced the number of new antibiotics in the last
three decades, resistance to these drugs by microorganisms has
increased because microorganisms are highly efficient at modifying
or acquiring genes that code for the mechanism of multidrug
resistance [3]. Compounding the problem of multidrug resistance, it
is necessary to search for new antimicrobial agents to combat
infections and overcome the problem of resistance and side effects
of currently available antimicrobial drugs. Several attempts have
been made for exploring new antimicrobial drugs from natural
sources including plant and animal products. In modern society, zoo-
therapy constitutes an important alternative among many other
known therapies practiced worldwide. Zootherapy is the healing of
diseases by use of therapeutics obtained or ultimately derived from
animals [4].
Fishes are a diverse group of animals and comprise almost half the
number of vertebrate species in existence today [5]. Approximately
20 million metric tons of fish by-products are discarded annually
from the world fisheries [6]. Fish by-products are rich in potentially
valuable proteins, minerals, enzymes, pigments or flavors. Fish
mucus, a fish by-product, is a key component of fish innate
immunity. It acts as innate defense barrier of fish skin which
continuously gets replaced and helps to prevent stable colonization
of majority of infectious microbes such as bacteria, fungus into the
fish body [7]. Fish mucus is secreted by epidermal goblet cells and
comprises of mucins and other substances such as inorganic salts,
immunoglobulin, proteins and lipids suspended in water giving it
characteristic lubricating properties [8]. The composition, viscosity,
and rate of mucus secretion vary from species to species and have
been observed to change in response to microbial exposure or to
environmental fluctuation such as hyperosmolarity and pH [9]. Fish
skin mucus has been reported to secrete many antibacterial
peptides [10-11]. Channa striatus is endowed with wound healing,
antinociceptive, platelet aggregation, anti-inflammatory as well as
mild antifungal and antibacterial properties [12]. In addition to
antimicrobial peptides, fish skin mucus also contains C-reactive
protein, lysozymes, lectin, flavoenzyme, immunoglobins etc. which
protects fishes against pathogenic microbes in their surroundings
[13-14]. Antibacterial properties of crude skin mucus from many
fishes have been demonstrated against several human and fish
pathogenic bacteria by many workers [6, 15-16]. H. nobilis is
omnivorous and feeds on larger phytoplankton mostly on algal
blooms [17], thus this species lines with an environment harboring
many infectious microbes. Thus, the present study was focused on
analyzing the biochemical characterization and antimicrobial
activity of skin mucus of H. nobilis.
MATERIALS AND METHODS
Fish collection and acclimatization
Live fish, H. nobilis irrespective of sex, weighing 800-900 grams
were purchased from the nearby fish culture pond and maintained
in F. R. P. tank (1000 L capacity) at Fish and Fisheries Laboratory,
Department of Zoology, Kurukshetra University, Kurukshetra. Half of
the water of the tank was changed on alternate days. Dissolved
oxygen was maintained at a preferable level in the tank with the
help of low-pressure aerators and pumps. The health of fishes was
observed daily, and dead fish or fish with lesions (if any) was
immediately removed. The fish were fed daily at 3% of body weight
with commercial/formulated feed during the acclimatization period.
Fish skin mucus collection
The fish were acclimatized for seven days and kept starved for 24 h
before mucus collection. A collection of mucus was done by 'skin-
scraping' from the body of test subjects. No anesthesia was given
prior to mucus collection. Mucus was taken from 15 fishes dorso–
International Journal of Pharmacy and Pharmaceutical Sciences
ISSN- 0975-1491 Vol 8, Issue 6, 2016
Tyor et al.
Int J Pharm Pharm Sci, Vol 8, Issue 6, 132-136
133
laterally by using a sterile plastic spatula. Mucus scraped first was
discarded to avoid any bacterial contamination. Collection of mucus
from ventral region of the fish was avoided to prevent mixing of
urinogenital excreta. Fish skin mucus was placed in vials and kept
frozen at 0 °C until use to avoid bacterial growth and protein
degradation.
Preparation of mucus extracts and biochemical characterization
Two mucus extracts viz. crude mucus extract and aqueous extract
were prepare from the previously preserved mucus. For crude
mucus extract skin mucus preserved from 15 fishes was thawed and
centrifuged at 5000 r. p. m for 5 min. The supernatant was subjected
to qualitative and quantitative assays to estimate the biochemical
constituents. To prepare aqueous mucus extract, collected mucus
was thoroughly mixed with equal quantity of sterilized physiological
saline (0.85% NaCl) and centrifuged at 5000 r. p. m for 5 minutes.
The supernatant was analyzed for biochemical constituents. Protein
analysis was done by Biuret test [18] and Lowry assays [19].
Carbohydrate content was estimated by Anthrone test [20] and
Phenol sulphuric acid reaction [21] and lipid analysis was
performed by free fatty acid test [22] and folch method [23].
Test microorganisms-procurement and maintenance
Antibacterial activity of fish skin mucus extracts was tested for six
human pathogenic bacteria E. coli, K. pneumoniae, P. aeruginosa
(Gram-negative bacterial strains), S. aureus, S. epidermidis and B.
cereus (Gram-positive bacterial strains) and a fish pathogenic
bacteria A. hydrophilla (Gram-negative strain). The bacterial strains
were obtained from Institute of Microbial Technology (IMTECH),
Chandigarh through Department of Biotechnology and Department
of Zoology, Kurukshetra University, Kurukshetra, India. All the
bacterial strains were grown in nutrient broth (0.5% peptone, 0.5%
NaCl, 0.3% beef extract, distilled water, pH adjusted to neutral (6.8)
at 28 °C) under biomedical safety protocols and conditions. 10 ml of
nutrient broth was poured in flask and one loop of target bacteria
was added to the flask and incubated for 24 h at 37 °C in incubator.
Antibacterial assay
In vitro antibacterial evaluation of fish skin, mucus extracts were
assayed by agar well diffusion method [24]. 100 µl culture of
different bacterial strains was spread on different culture plates
containing 15 ml of nutrient agar media [1.5% agar-agar, 0.5%
peptone, 0.5% NaCl, 0.3% beef extract, distilled water, pH adjusted
to neutral (6.8) at 28 °C] by using a sterile cotton swab. Wells were
made with the help of cork borer on the agar nutrient media plates
suitably spaced apart. 100 µl of both mucus extracts, crude and
aqueous were loaded in wells on different plates. The plates were
then incubated at 37 °C for 24 h. The antibacterial activity was assayed
by measuring the diameter (mm) of the inhibition zone formed around
the well [25]. Amikacin and Chloramphenicol drugs were used to
compare the antibacterial effect of fish mucus extracts. NaCl was used
as the negative control along with two antibiotics in the determination
of antimicrobial activity of aqueous mucus extract. Experiments were
conducted in triplicates to determine the reproducibility.
Minimum inhibitory concentration
MIC represents the lowest concentration of an antimicrobial
substance that inhibits the growth of a microorganism. Agar plate
dilution test [26] was performed to determine the MIC of crude skin
mucus extract against all selected microbes. Desired concentrations
of crude mucus extract were prepared by volume/volume dilution
with distilled water and poured in different wells on nutrient agar
plates. Plates were incubated at 37 °C for 24 h.
Statistical analysis
The data so obtained were pooled separately for each parameter and
expressed throughout as means±SE Significant difference in
antimicrobial activity of fish skin mucus of different fishes among
groups was tested by Analysis of variance (ANOVA) Duncan’s
multiple range tests for the experiments. Statistical significance was
settled at a probability value of P<0.05. All statistics were performed
using SPSS Version 11.5 for Windows.
RESULTS
H. nobilis huge secrete amount of mucus which was viscous in
nature. We collected 10-15 ml of mucus/day. In our study, we also
noticed that amount of mucus secretion also vary according to the
season. H. nobilis was reported to secrete more mucus in summer
than in winter.
Biochemical characterization
The presence of proteins in fish skin mucus sample was confirmed
by Biuret test. Change in the colour of skin mucus sample from blue
to purple or violet indicated the presence of proteins. Similarly,
colour change in skin mucus sample from light yellow to blue-green
indicated the presence of carbohydrates in skin mucus of H. nobilis.
Skin mucus sample of H. nobilis gave pink color solution after
addition of dilute alkaline (0.1% NaOH) thus confirming the
presence of free fatty acids in the sample.
The results for quantitative analysis of fish skin mucus have been
presented in table 1.
Table 1: Concentration of biochemical constituents of skin mucus of H. nobilis
Parameters
Value
Protein (µg/ml)
265.00±2.64
Carbohydrate (µg/ml)
63.66±0.88
Lipids (g/ml)
0.0077±0.06
All values are mean±SE of mean, Value of n (No. of experiments) = 6
Table 2: Zone of inhibition (mm) shown by crude mucus extract of H. nobilis against different bacterial strains
Fish
Microbial strains
Crude mucus extract
Amikacin
Chloramphenicol
K. pneumonia
23.58±0.67Bd
33.50±0.458Aab
17.33±0.19Cd
E. coli
32.66±0.56Ba
33.50±0.56Aab
25.66±0.19Ca
P. aeruginosa
27.62±0.62Bc
33.00±0.40Abc
18.33±0.34Cd
S. epidermidis
32.83±0.49Aa
32.00±0.23Ac
21.16±1.29Bbc
B. cereus
29.25±0.57Bb
34.50±0.31Aa
24.43±0.31Ca
S. aureus
26.33±0.96Bc
32.16±0.34Abc
22.16±0.51Cb
A. hydrophilla
25.93±0.71Bc
33.33±0.19Aabc
20.00±0.16Cc
ZOI also include well diameter, All values are mean±SE of mean, Means with different letters in upper case in the same row are significantly
(P<0.05) different., Mean with different letters in lower case in the same column are significantly (P<0.05) different., (Data were analyzed by
Duncan’s Multiple Range test), Value of n (No. of experiments) = 6
Tyor et al.
Int J Pharm Pharm Sci, Vol 8, Issue 6, 132-136
134
Table 3: Zone of inhibition (mm) shown by aqueous mucus extract of H. nobilis against different bacterial strains
Fish
Microbial strains
Aqueous mucus
Amikacin
Chloramphenicol
K. pneumonia
13.16±0.49Bbc
26.36±0.93Aa
10.00±00Cb
E. coli
16.55±1.10Ba
25.26±0.62Aab
12.70±0.21Ca
P. aeruginosa
12.73±0.51Bc
25.86±1.38Aa
08.73±0.50Cc
S. epidermidis
16.71±1.04Ba
23.11±1.10Aab
10.10±0.33Cb
B. cereus
15.85±0.94Bab
22.66±0.95Aab
12.13±0.07Ca
S. aureus
11.58±0.50Bc
23.03±1.23Aab
10.06±0.03Bb
A. hydrophilla
16.03±1.16Bab
21.75±1.01Ab
12.76±0.17Ca
ZOI also include well diameter, All values are mean±SE of mean, Means with different letters in upper case in the same row are significantly
(P<0.05) different. Mean with different letters in lower case in the same column are significantly (P<0.05) different, (Data were analyzed by
Duncan’s Multiple Range test), Value of n (No. of experiments) = 6
Table 4: MIC shown by skin mucus extract of H. nobilis against different bacterial strains
Microbial strains
K. pneumonia
E. coli
P. aeruginosa
S. epidermidis
B. cereus
S. aureus
A. hydrophilla
MIC (µl/ml)
25.00
25.00
50.00
50.00
25.00
50.00
50.00
ZOI (mm)
7.00±00
7.00±00
12.73±0.51
16.71±1.04
20.38±6.11
11.58±0.50
16.03±1.16
ZOI also include well diameter, All values of ZOI are mean±SE of mean, Value of n (No. of experiment) = 6 (for both MIC and ZOI)
Antibacterial assay
Effect of crude mucus extract and aqueous mucus extract of H.
nobilis against microbial strains has been presented in table 2 and
table 3 respectively. Both crude and aqueous fish skin mucus
extracts exhibited the ZOI against all tested bacterial strains. Crude
skin mucus extract exhibited maximum ZOI against S. epidermidis
(32.83±0.49 mm) followed by E. coli (32.66±0.56 mm).
In S. epidermidis, ZOI was higher than both the antibiotics, amikacin
(32.00±0.23 mm) and chloramphenicol (21.69±1.29 mm). Crude
mucus extract showed significantly higher ZOI than chloramphenicol
whereas it was insignificant when compared with amikacin (table
2). When the antibacterial activity of aqueous fish mucus extracts
against selected bacterial strains was compared with amikacin and
chloramphenicol, amikacin showed a significantly higher ZOI followed
by fish mucus extract and chloramphenicol. Aqueous fish skin mucus
extract showed maximum ZOI against S. epidermidis (16.71±1.04 mm)
followed by E. coli (16.55±1.10 mm) and A. hydrophilla (16.03±0.16
mm). No ZOI was shown by negative control (NaCl).
In the case of MIC assay, inhibitory concentration of mucus extract
was found to vary for different microbial strains tested. MIC of crude
mucus extract of H. nobilis was found in the range of 25 µl/ml to 50
µl/ml (table 4).
DISCUSSION
Fish skin mucus acts as the first line of defense against microbes [11,
27-28]. Negus (1963) reported that scaleless fishes produce a higher
amount of epidermal mucus than fish with scale [29]. Although
bighead is scaly fish, it also secretes a large amount of mucus. The
quantity and quality of mucus have been reported to differ according
to the season, environmental conditions such as pH, handling stress
and age of fish [30-31] which also supports our findings that amount
of mucus secretion was more in summers as compared to winters.
All these factors play an important role in the susceptibility of a fish
to infection [9, 13].
Crude mucus extract of H. nobilis is constituted of protein as a major
component followed by carbohydrate and lipids. Manivasagan et al.
(2009) investigated that soluble gel of A. maculates was having
12.64 µg/g of protein content,0.08 µg/g of carbohydrate content and
0.005 µg/g of lipid content[32] which also supports our results. Wei
et al. (2010) also reported protein content in both crude and
aqueous mucus extract of Channa straitus [6]. Dhotre et al. (2013)
also characterized the biochemical composition of freshwater fishes
viz. Channa punctatus, Channa gachua, C. carpio and A. dussmieri [33]
and found similar results. Similarly, protein has been reported as a
major component of fish skin mucus of six freshwater fishes viz.
Clarias gariepinus, Channa micropeletes, C. straitus, Oreochromis
niloticus and Hemibagrus nemurus [34]. The presence of protein
content was also investigated in the epidermal mucus of Gaint
snakehead, striped snakehead, Tilapia mossambicus and bagrid
catfish [35]. Our results also go in agreement with the above studies.
Review of the literature reveals that high amount of protein may be
responsible for antibacterial activity shown by fish skin mucus [6,
32, 34-38]. Over the past few years, many antibacterial peptides
have been isolated from different a fish which provides a non-
specific innate immune system to fishes against various pathogen
and help fishes to survive in adverse conditions [36, 38-40].
Crude mucus extract of H. nobilis exhibited strong antibacterial
activity against all selected microbes. The Strong antibacterial
activity of crude fish skin mucus extract has also been observed in
other similar studies [15, 36, 41-42]. Wei et al. (2010) observed that
both crude mucus extract and aqueous mucus extract of C. straitus
showed inhibitory effect against fish pathogenic bacteria A.
hydrophilla (8 mm) and no inhibitory effect against human
pathogenic bacteria E. coli and K. pneumonia [6] whereas crude and
aqueous mucus extract of H. nobilis showed strong antibacterial
activity against both fish and human pathogenic bacteria.
Bragadeeswaran and Thangraj (2011) noticed that crude mucus
extract of eel fish show a strong inhibitory effect against E. coli, P.
aeruginosa and S. aureus and no activity was observed against K.
pneumonia. In the same study, they reported that aqueous mucus
extract was not effective against P. aeruginosa [43]. However, crude
mucus, as well as aqueous mucus extract of H. nobilis, exhibited
antibacterial activity against all the four bacteria tested by
Bragadeeswaran and Thangraj (2011). Loganathan et al. (2013)
reported the inhibitory effect of crude mucus extract of C. straitus
against E. coli, S. aureus and Aermonas sp.[44]. Our findings on crude
mucus extract are in the agreement with above study. Mucus extract
of C. gaucha, C. punctataus, C. carpio and A. dussumieri showed no
ZOI against K. pneumonia [33]. Rao et al. (2015), did not notice the
inhibitory effect of crude and aqueous mucus extract of C.
micropeltes, C. straitus, Chrysichtys nigrodigitatus and T.
mossambicus against E. coli. However, crude and aqueous mucus
extract of H. nobilis exhibited strong antibacterial activity against E.
coli as well as K. pneumonia in contrary [33, 35]. Aqueous mucus
extract of H. nobilis also exhibited strong antibacterial activity
against all pathogenic bacteria taken under study but comparatively
lesser than antibacterial activity shown by crude mucus extract.
Strong inhibitory effect of aqueous mucus extract shown by a variety
of fishes Arius caelatus, A. maculates, C. striatus, Clarias batrachus,
Cynoglossus arel, Hertropneustes fossilis and Mystus gulio [43, 45-48]
support our findings on aqueous mucus extract. Subramanian et al.
(2007) also reported the presence of antimicrobial compounds in
aqueous mucus extract [38]. But in their further studies no
antibacterial activity was observed in aqueous mucus extract of
Tyor et al.
Int J Pharm Pharm Sci, Vol 8, Issue 6, 132-136
135
wider range of fish species including Arctic char (Salvelinus alpinus)
brook trout (Salvelinus fontinalis), Koi carp (C. carpio), striped bass
(Morone saxatalis), haddock fish (Melanogrammus aeglefinus) and
hagfish (Myxine glutinosa)[11]. Strong antibacterial activity
exhibited by aqueous mucus extract of two indigenous fish (Catla
catla and Labeo rohita) and two exotic fishes (Hypophthalmichthys
molitrix and Ctenopharyngodon idella) [49] which also supports our
findings. On comparing the results of Balasubramanian et al. (2012)
with our study, H. molitrix was found to show higher antibacterial
activity than H. Nobilis. Kumari et al. (2011) [16] reported
antibacterial activity of aqueous mucus extract Rita rita and Channa
punctatus against S. arueus (9.75±1.70 mm) but at the same time, no
antibacterial activity was reported against E. coli and P. aeruginosa.
However, our results showed that aqueous mucus extract of H.
nobilis exhibit maximum antibacterial activity against E. coli
(16.55±1.10 mm) followed by P. aeruginosa (12.73±0.51 mm) and
minimum against S. aureus. (2008) [15] also studied the inhibition
effect of aqueous mucus extract of Channa punctatus and Cirrhinus
mrigala against ten pathogenic strains out of which 4 bacterial
strains viz. E. coli, K. pneumonia, P. aureginosa and S. aureus are
common with the present study. Our findings are in agreement with
Kuppulakshmi et al. (2008) [15].
However, contradictory to our result no antibacterial activity was
observed in aqueous mucus extract of 13 fish species [10]. Our
observation on aqueous mucus extract also supports the reports on
the antimicrobial nature of hydrolytic enzymes such as lysoymes,
cathepsin B, trypsin-like proteases in fish mucus [11, 50-52]. Fish
mucus extracts of H. nobilis were found to show strong inhibition
effect against all the microbial strains taken under study. Thus,
suggesting the presence of one or more antibacterial components in
fish skin mucus of H. nobilis. Paradaxin pore forming a peptide, from
Moses fish Pardachius marmoratus [41] and pleurocidin in skin
secretion of winter flounder [36] have been isolated. Ebran et al.
(1999) also reported pore forming properties of protein extracted
from fish epidermal mucus [53]. The action of these antibacterial
peptides is non-specific and rapid; they kill bacteria by a pore
formation in cell membranes followed by disruption and
solubilization [53]. Thus, we may assume that strong antimicrobial
activity of epidermal mucus extracts of H. nobilis against microbial
strains may be due to pore formation ability of their antibacterial
peptides in target cell membrane.
MIC assay was carried out on mucus extracts of some fishes such as
C. statius, Desyatis sephen and Himantura gerradi against many
human and fish pathogenic bacterial strains [6-7]. Rao et al. (2015)
reported the MIC value of Gaint snakehead, striped snakehead,
tilapia and bagrid catfish (C. nigrodigitatus) against different
pathogen ranged from 11.96µg/ml to 31.91 µg/ml. The MIC values
reported in these works was not similar to those obtained in our
study. In our study the minimum concentration of 50 µl/ml of skin
mucus extract of H. nobilis was found to inhibit the growth of human
pathogenic bacteria S. epidermidis, S. areus, P. aeruginosa and fish
pathogen, A. hydrophilla. The minimum concentration of 25 µl/ml
was adequate to inhibit the growth of K. pneumonia, B. cereus and E.
coli. Same fish or different fishes exhibited different antibacterial
activity against different or same bacterial strains. This may be due
to difference in their age, geological and physiological conditions.
Thus, skin mucus extract of H. nobilis needs to be characterized
further, and can be explored as a potent antimicrobial against
infectious bacteria.
CONCLUSION
The present findings suggest that epidermal mucus of H. nobilis is a
good source of antimicrobial compounds. This antimicrobial activity
might be due to antimicrobial proteins present in epidermal mucus
as protein was found to be the major component of mucus. The
epidermal mucus extracts of H. nobilis showed a different zone of
inhibition against different bacterial strains. Thus, indicating
antimicrobial activity of skin mucus of H. nobilis. Further, a detailed
investigation is required for purification and characterization of
specific antimicrobial components of epidermal mucus so that it may
be utilized as potent anti microbe.
ACKNOWLEDGEMENT
The authors are thankful to Department of Zoology, Kurukshetra
University for providing all necessary facility for the study. We are
also grateful to Dr. Sunita Dalal for providing us microbial strains.
CONFLICT OF INTERESTS
The authors declare that there is no conflict of interest regarding the
publication of this paper
REFERENCES
1. Roder BL. Clinical features of Staphylococcus aureus
endocarditis. A 10-year experience in Denmark.
Arch Intern Med 1999;159:462–9.
2. Harbottle H, Thakur S, Zhao S, White DG. Genetics of
antimicrobial resistance. Anim Biotechnol 2006;17 Suppl
2:111-24.
3. Shoemaker NB. Evidence for extensive resistance gene transfer
among Bacteroides spp. and among Bacteriodes of other
genera in the human colon. Appl Environ Microbiol
2001;67:561-8.
4. Costa-Neto EM. Healing with an animal in Feira de Santana City,
Bahia, Brazil. J Ethnopharmacol 1999;63:2225-30.
5. Schaeck M, Broeck WAD, Hermans K, Decostere A. Fish as a
research tool: an alternative to in vivo experiments. ALTA
2013;41:219-29.
6. Wei OY, Xavier R, Marimuthu K. Screening of antibacterial
activity of mucus extract of snakehead fish, Channa straitus
(Bloch). Eur Rev Med Pharmacol Sci 2010;14:675-81.
7. Vennila R, Kumar RK, Kanchana S, Arumugam M, Vijayalakshmi
S, Balasubramaniam T. Preliminary investigation on the
antimicrobial and proteolytic property of the epidermal mucus
secretion of marine stingrays. Asian Pac J Trop Biomed
2011;1:239-43.
8. Pearson J, Brownlee IA. A surface and function of mucosal
surface. In: Colonization of the mucosal surface, Nataro JP (Ed.).
ASM Press: Washington DC, USA; 2005.
9. Aggarwal SK, Banerjee TK, Mittal AK. Physiological adaptation
in relation the hyperosmotic stress in the epidermis of a
freshwater teleost Barbus sophor (Cypriniformes: Cyprinidae) a
histochemical study. Z Mikrosk Anat Forsch 1979;93:51-64.
10. Hellio C, Bremer G, Pons AM, Le Gal Y, Bourgougnon N.
Antibacterial, antifungal and cytotoxic activities of extracts
from the fish epidermis and epidermal mucus. Int J Antimicrob
Agent 2002;20:214-9.
11. Subramanian S, Ross NW, MacKinnon SL. Comparison of
antimicrobial activity in the epidermal mucus extracts of fish.
Comp Biochem Physiol Part B: Biochem Mol Biol 2008;150
Suppl 1:85-92.
12. Subramanian S, Ross NW, MacKinnon SL. Myxinidin, a novel
antimicrobial peptide from the epidermal mucus of hagfish,
Myxine glutinosa. L. J Mar Biotechnol 2009;11:748–57.
13. Ellis AE. The immunology of teleosts. In: Roberts RJ. Fish
Pathol. 3rd edition. Elsevier, New York; 2001. p. 133-50.
14. Whyte SK. The innate immune response of finfish-A review of
current knowledge. Fish Shell Fish Immunol 2007;23:1127-51.
15. Kuppulakshmi C, Prakash M, Gunasekaran G, Manimegalai G,
Sarojini S. Antibacterial properties of fish mucus from Channa
punctatus and Cirrhinus mrigala. Eur Rev Med Pharmacol Sci
2008;12:149-53.
16. Kumari U, Nigam AK, Mitial S, Mitial AK. Antibacterial
properties of the skin mucus of the freshwater fishes, Rita rita
and Channa punctatus. Eur Rev Med Pharmacol Sci 2011;15
Suppl 7:781-6.
17. Gopakumar K, Ayyappan S, Jena JK, Sahoo SK, Sarkar SK,
Satapathy BB, et al. Cyprinid Fishes. National freshwater
aquaculture development plan. CIFA, Bhubaneswar, India;
1999. p. 75.
18. Smith PK. Measurement of protein using bicinchonic acid. Anal
Biochem 1985;150:76-85.
19. Lowry OH, Rosenbrough NJ, Farr AL, Randall RJ. Protein
measurement with the folin phenol reagent. J Biol Chem
1951;193:265-75.
Tyor et al.
Int J Pharm Pharm Sci, Vol 8, Issue 6, 132-136
136
20. Trevelyan WE, Forrest RS, Harrison JS. Determination of yeast
carbohydrate with the anthrone reagent. Nature
1952;170:626-7.
21. Dubois M, Gilles KA, Hamilton JK, Rebers PA, Smith F.
Colorimetric method for determination of sugars and related
substances. Anal Chem 1956;28:350-6.
22. Novk M. Colorimetric ultra micro method for determination of
free fatty acids. J Lipid Res 1965;6:67-9.
23. Folch JM, Lees, Stanely GHS. A simple method for isolation and
purification of total lipids from animal tissue. J Biol Chem
1957;226:497-9.
24. Perez C, Pauli M, Bazerque P. An antibiotic assay by agar well
dilution method. Acta Biol Med Exp 1990;15:113-5.
25. National Committee for Clinical Laboratory Standards (NCCLS).
Methods for dilution antimicrobial susceptibility test for
bacteria that grow aerobically, Third edition. Approved
standard. M7-A3. NCCLS: Villanova, PA, USA; 1993.
26. National Committee for Clinical Laboratory Standards (NCCLS).
Methods for dilution antimicrobial susceptibility tests for
bacteria that grow aerobically. Approved standard fifth Edition.
NCCLS document M7-A5. NCCLS: Wayne, PA,USA; 2000.
27. Austin B, MacIntosh D. Natural antibacterial compounds on the
surface of rainbow trout, Salmo gairdneri. Richardson. J Fish
Dis 1988;11:275-7.
28. Fouz B, Devesa S, Gravningen K, Barja J, Toranzo A.
Antibacterial action of the mucus of the turbot. Bull Eur Ass
Fish Pathol 1990;10:56-9.
29. Negus VE. The function of mucus. Acta Otolaryngol
1963;56:204-14.
30. Black SN, Pickering AD. Changes in the concentration and
histochemistry of epidermal mucus cells during the alevin and
fry stages of the brown trout (Salmo trutta). J Zool Sci
1982;197:463-71.
31. Lebedeva NY. Skin and superficial mucus of fish. Biochemical
properties and functional role. In: Saksena Ichthyol Rec Res
Adv Sci Pub. New. Ham; 1999. p. 179-93.
32. Manivasagan P, Annamalain N, Ashok KS, Sampath KP. A study on
the proteinaceous gel secretion from the skin of the catfish, Arius
maculates (Thunberg, 1792). Afr J Biotechnol 2009;8:7125-9.
33. Dhotre MA, Bansode PD, Shembekar VS. Extraction,
Biochemical characterization and antibacterial activity of fish
mucus. Indian Streams Res J 2013;2 Suppl 12:1-8.
34. Timalata K, Marimuthu K, Vengkades R, Xavier R, Rahman MA,
Sreeramanan S, et al. Elucidation of innate immune
components in the epidermal mucus of different freshwater
fish species. Acta Ichthyol Piscatoria 2015;45 Suppl 3:221-30.
35. Rao V, Marimuthu K, Kupusamy T, Rathinam X, Arasu MV, Al-
Dhabi NA, et al. Defense properties in the epidermal mucus of
different freshwater fish species. AACL Bioflux 2015;8 Suppl
2:184-94.
36. Cole AM, Weis P, Diamond J. Isolation and characterization of
pleurocidin, an antimicrobial peptide in the skin secretions of
winter flounder. J Biochem 1997;272:12008-13.
37. Ebran N, Julien S, Orange N, Saglio P, Lemaitre C, Molle G. Pore-
forming properties and antibacterial activity of proteins
extracted from the epidermal mucus of fish. Comp Biochem
Physiol 1999;122:181-9.
38. Subramanian S, MacKinnon S, Ross NW. A comparative study
on innate immune parameters in the epidermal mucus of
various fish species. Comp Biochem Physiol. Part B: Biochem
Mol Biol 2007;148 Suppl 3:256-63.
39. Boman HG. Peptide antibiotics and their role in innate
immunity. Annu Rev Immunol 1995;13:61-92.
40. Fernandes JMO, Molle G, Kemp GD, Smith J. Isolation and
characterization of oncorhyncin II, a histone H1-derived
antimicrobial peptide from skin secretions of rainbow trout,
Oncorhynchus mykiss. Dev Comp Immunol 2004;28 Suppl
2:127-38.
41. Oren Z, Shai Y. A class of highly potent antibacterial peptides
derived from pardaxin, a pore-forming peptide isolated from
Moses fish Pardachius marmoratus. Eur J Biochem 1996;237:3.
42. Krishnamurthi E, Ranjini S, Rajagopal T, Rameshkumar G,
Ponmanickam P. Bactericidal protein of skin mucus and skin
extracts from freshwater fishes, Clarias batrachus and Tilapia
mossambicus. Thai J Pharm Sci 2013;37:194-200.
43. Bragadeeswaran S, Thangaraj S. Hemolytic and antibacterial
studies on skin mucus of eel fish, Anguilla linnaues 1758. Asian
J Biol Sci 2011;4 Suppl 3:272-6.
44. Loganathan K, Arul PA, Prakah M, Senthilraja P, Gunaesekaran
G. studies on the antimicrobial and hemolytic activity of the
mucus of freshwater snakehead fish Channa striatus. Int J Biol
Pharm Allied Sci 2013;2 Suppl 4:866-78.
45. Anbuchezhian R, Gobinath C, Ravichandran S. Antimicrobial
peptide from the epidermal mucus of some estuarine catfishes.
The World Appl Sci J 2011;12 Suppl 3:256-60.
46. Loganathan K, Muniyan M, Arul PA, Senthil RP, Prakash M.
Studies of the role of mucus from Clarias batrachus (LINN)
against selected microbes. Int J Pharm 2011;2 Suppl 3:202-6.
47. Uthyakumar V, Ramasubramanian V, Senthilkumar D,
Priyadarisini BV, Harikrishan A. Biochemical characterization,
antimicrobial and hemolytic studies on skin mucus of
freshwater spiny eel, Mastacembelus armatus. Asian J Trop
Biomed 2012;2:S863-S869.
48. Haniffa MA, Viswanathan S, Jancy D, Poomari K, Manikandan S.
Antibacterial studies of fish mucus from two marketed air-
breathing fishes–Channa striatus and Heteropneustes fossilis. Int
Res J Microbiol 2014;5 Suppl 2:22-7.
49. Balasubramanian S, Baby Rani P, Prakash AA, Prakash M.
Antimicrobial properties of skin mucus from four freshwater
cultivable Fishes (Catla catla, Hypophthalmichthys molitrix,
Labeo rohita and Ctenopharyngodon idella). Afr J Microbiol Res
2012;6 Suppl 24:5110-20.
50. Takahashi Y, Kajiwaki T, Itami T, Okarnoto T. Enzymatic
properties of the bacteriolytic substances in the skin mucus of
yellow tail. Nippon Suisan Gakkaishi 1987;53:425-31.
51. Aranishi F. The high sensitivity of skin cathepsins L and B of
European eel (Anguilla anguilla) to thermal stress. Aquaculture
2000;182:209-13.
52. Smith VJ, Fernandes JMO, Jone SJ, Kemp GD, Tatner MF.
Antibacterial protein in rainbow trout, Oncorhynchus mykiss.
Fish Shellfish Immunol 2000;10:243-60.
53. Andreu D, Rivas L. Animal antimicrobial peptides: an overview.
Biopolymers 1999;47:415-33.
