ArticlePDF Available

Antimicrobial properties of skin mucus from four freshwater cultivable Fishes (Catla catla, Hypophthalmichthys molitrix, Labeo rohita and Ctenopharyngodon idella)

Authors:

Abstract and Figures

The fishes are living in the medium rich in pathogenic microbes. The mucus secreted by the skin of fish showed more antimicrobial properties. The mucus collected from the two exotic fishes and two indigenous fishes were tested against the five pathogenic bacteria (Klebsiella pneumonia, Vibrio cholerae, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa) and five pathogenic fungi namely (Mucor globosus, Rhizopus arrhizus, Candida albicans, Aspergillus flavus and Aspergillus niger). The fishes are living in media rich in pathogenic microbes which secrete substances against them. The mucus secreted by the skin of fish showed more antimicrobial properties. More antibacterial and antifungal activity were observed in an indigenous fishes (Catla catla and Labeo rohita) than exotic fishes (Hypophthalmichthys molitrix and Ctenopharyngodon idella).
Content may be subject to copyright.
African Journal of Microbiology Research Vol. 6(24), pp. 5110-5120, 28 June, 2012
Available online at http://www.academicjournals.org/AJMR
DOI: 10.5897/AJMR11.532
ISSN 1996-0808 ©2012 Academic Journals
Full Length Research Paper
Antimicrobial properties of skin mucus from four
freshwater cultivable Fishes
(Catla catla, Hypophthalmichthys molitrix, Labeo rohita
and Ctenopharyngodon idella)
Balasubramanian S., Baby Rani P., Arul Prakash A., Prakash M.*, Senthilraja P.
and Gunasekaran G.
Department of Zoology, Annamalai University, Annamalai Nagar, Chidambaram-608002, TN, India.
Accepted 24 August, 2011
The fishes are living in the medium rich in pathogenic microbes. The mucus secreted by the skin of
fish showed more antimicrobial properties. The mucus collected from the two exotic fishes and two
indigenous fishes were tested against the five pathogenic bacteria (Klebsiella pneumonia, Vibrio
cholerae, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa) and five pathogenic fungi
namely (Mucor globosus, Rhizopus arrhizus, Candida albicans, Aspergillus flavus and Aspergillus
niger). The fishes are living in media rich in pathogenic microbes which secrete substances against
them. The mucus secreted by the skin of fish showed more antimicrobial properties. More antibacterial
and antifungal activity were observed in an indigenous fishes (Catla catla and Labeo rohita) than exotic
fishes (Hypophthalmichthys molitrix and Ctenopharyngodon idella).
Key words: Antibacterial, antifungal, fish mucus, exotic, indigenous fish.
INTRODUCTION
Chemicals from nature have been a part of human
civilization ever since our early ancestor’s began
exploiting natural compounds to improve and enrich their
own lives (Agosta, 1996). A major part of these chemicals
come from animals. Indeed, animals are therapeutic
arsenals that have been playing significant roles in the
healing processes, magic rituals, and religious practices
of peoples (Costa and Marques, 2000). All living
organisms including fish coexist with a wide range of
pathogenic and non- pathogenic microorganisms and
therefore, posses complex defense mechanisms which
contribute to their survival. One mechanism is the innate
immune system that combats pathogens from the
moment of their first contact (kimbrell and Beutler, 2001).
The specific immunity including antibody and specific
cell-mediated responses are significantly less diverse
*Corresponding author. E-mail: dnaprakash@gmail.com.
than those of higher (Ellis, 1974; Manning, 1998).
The development of resistance by a pathogen to many
of the commonly used antibiotics provides an impetus for
further attempts to search for new antimicrobial agents,
which overcome the problems of resistance and side
effects. Action must be taken to reduce this problem such
as controlling the use of antibiotics, carrying out research
to investigate drugs from natural sources. Drugs that can
either inhibit the growth of pathogen or kill them and have
no or least toxicity to the host cell are considered for
developing new antimicrobial drugs. It is well known that
the global trade in animal based medicinal products
accounts for billions of dollars per year (Kunin and
Lawton, 1996). Unlike conventional antibiotics, which are
synthesized enzymatically by microorganisms, are
encoded by a distinct gene (AMP) and made from an
mRNA template. The continuous use of antibiotics has
resulted in multi resistant bacterial strains all over the
world (Mainous and Pomeroy, 2001). Consequently,
there is an urgent need to search for alternatives
to synthetic antibiotics. In spite of modern improvements
in chemotherapeutic techniques, infectious diseases are
still an increasingly important public health issue (WHO,
2002). It has been estimated that in 2000, at least two
million people died from diarrhoeal disease worldwide
(WHO, 2002). Still there is a need for new methods of
reducing or eliminating pathogens, possibly in
combination with existing methods (Leistner, 1978). In
the aquatic environment, fish are in constant interaction
with a wide range of pathogenic and non-pathogenic
microorganisms (Subramanian et al., 2007).
Fish live in a challenging environment facing so many
problems. The microbes play a major role in affecting the
fish health. They escape from such an environment by
producing some substances on the dermal layer (Mucus).
The epidermal mucus produced primarily by epidermal
goblet or mucus cells are composed mainly of water and
gel forming macromolecules including mucins and other
glycoproteins (Shephard, 1993). The composition and
rate of mucus secretion has been observed to change in
response to microbial exposure or to environmental
perturbation such as hyperosmolarity and acidity
(Agarwal et al., 1979; Zuchelkowski et al., 1981; Ellis,
2001). The mucus substance secreted from the surface
of fish performs a number of functions including disease
resistance, respiration, ionic and osmotic regulation,
locomotion, reproduction, communication, feeding and
nest building (Ingram, 1980; Fletcher, 1978). Despite an
intimate contact with high concentrations of pathogens
(bacteria and viruses) in their environment, the fish can
still maintain a healthy system under normal conditions.
This could be attributed to a complex system of innate
defense mechanisms within themselves, particularly the
products of broad spectrum-antimicrobial compound.
Many researchers have proved that the mucus
substances are good resistant to invading pathogens
(Ingram, 1980; Fletcher, 1978; Austin and Mcintosh,
1988; Fouz et al., 1990).
Fish mucus (slime layer) is the first physical barrier that
inhibits entry of microbes from an environment into fish. It
acts as a chemical barrier containing enzymes and
antibodies which can kill invading disease causing
organisms (Rottmann et al., 1992). A fatty acid
compositional study of the flesh of Haruan (Channa
striatus) revealed those unusually high arachidonic acids,
but almost no eicosapentaenoic acids, which were
hypothesized to be actively involved in initiating tissue
wound repair (Mat Jais et al., 1994). Antimicrobial activity
in mucus has been demonstrated in several fish species
(Austin and Mcintosh, 1988), yet this activity seems to
vary from one fish species to the other and can be
specific towards certain bacteria (Noga et al., 1995).
When we are reviewing the literature among the fresh
water fishes the studies are available mostly on cold
water fishes.
Studies are available on C. striatus, Cyprinus carpio
(Cole et al., 1997) and Etheostoma crossopterum (Knouft
Balasubramanian et al. 5111
et al., 2003). Though studies are available on the
microbicidal activities of fish mucus they are pertaining
only against bacteria except a single study against fungi
(Hellio et al., 2002). Antimicrobial activity was
demonstrated in Channa punctatus and Cirrhinus mrigala
(Kuppulakshmi et al., 2008). Antimicrobial activity of skin
and intestinal mucus of five different freshwater fish
Channa species was studied by Dhanraj et al. (2009).
Apart from these no studies are available on the mucus
of the cultivable fresh water fishes like Catla catla, Labeo
rohita (Indigenous fishes), Hypophthalmichthys molitrix
and Ctenopharyngodon idella (Exotic fishes).
Hence it was decided to evaluate the bactericidal and
fungicidal properties of surface and column feeders
namely C. catla, H. molitrix, Labeo rohita and
Ctenopharyngodon idella. In the present investigation few
microbial species of bacteria such as, Klebsiella
pneumonia, Vibrio cholerae, Salmonella typhi,
Escherichia coli, Pesudomonas aeruginosa and fungi,
Mucur globosus, Rhizopus arrhizus, Candida albicans,
Aspergillus flavus and Aspergillus niger were selected.
MATERIALS AND METHODS
Collection of mucus
The healthy live fishes approximately 6 months old, weigh about
500 gms of each C. catla, L. rohita, H. molitrix C. idella were
purchased from near by fish farm in Pinnalur, Cuddalore District,
Tamil Nadu. Mucus was carefully scraped from the dorsal surface
of the body using a sterile spatula. Mucus was not collected in the
ventral side to avoid intestinal and sperm contamination. The
collected fish mucus was stored at 4ºC for further use.
Preparation of mucus sample for the antibacterial and
antifungal studies.
The mucus samples were collected aseptically from the fish and
thoroughly mixed with equal quantity of sterilized physiological
saline (0.85% NaCl) and centrifuged at 5000 rpm for 15 min, the
supernatant was used for the antimicrobial studies and kept at 4°C
until use.
A thin layer of molten agar (Muller Hinton Agar) was dispensed in
petriplates of 10 × 10 cm and was labled properly. Triplicates were
maintained for each strain. In the same way for fungal studies PDA
medium was dispensed in petriplates for different strains of fungi in
triplicates and the plates were marked.
Inoculation of bacterial strains
The microbial strains were collected from the Balaji High-tech
Laboratory in Manjakuppam, Cuddalore district, Tamil Nadu.
In vitro antibacterial assay was carried out by disc diffusion
technique (Bauer et al., 1996). Whatman No.1 filter paper discs
with 4 mm diameter were impregnated with known amount (10 µl)
of test sample of fish mucus and a standard antibiotic disc. At room
temperature (37ºC) the bacterial plates were incubated for 24 h.
The fungal plates were incubated at 30ºC for 3 to 5 days for
antifungal activity. The results were recorded by measuring the
zones of growth inhibition surrounding the disc. Clear inhibition
zones around the discs were expressed in terms of diameter of
5112 Afr. J. Microbiol. Res.
Table 1. Antibacterial activity of skin mucus from Catla and Silver carp.
S/N
Name of the Bacterial Pathogens
Zone of inhibition (in mm)
Control (Ciproflaxin)
(in mm)
Catla
Silver carp
1
K. pneumonia
25
22
24
2
V. cholerae
21
20
22
3
S. typhi
32
15
28
4
E. coli
23
16
22
5
P. aeruginosa
29
22
32
Table 2. Antibacterial activity of skin mucus from Rohu and Grass carp.
S/N
Name of the Bacterial Pathogens
Control
(Ciproflaxin) (in mm)
Rohu
Grass carp
1
K. pneumonia
24
7
24
2
V. cholerae
21
7
22
3
S. typhi
14
12
28
4
E. coli
21
17
22
5
P. aeruginosa
19
15
32
zone of inhibition and were measured in mm using cm scale,
recorded and the average were tabulated.
Antimicrobial assay
The spectrum of antimicrobial activity was studied using five
different strains of human pathogenic bacteria and five species of
fungal pathogens. One antibiotic agent Ciproflaxin for pathogenic
bacteria and Ketoconazole for pathogenic fungi were used as
control.
RESULTS
Antimicrobial effect of the mucus of surface feeder and
column feeder freshwater fishes namely, C. catla, H.
molitrix (Surface feeder), L. rohita (Column feeder), C.
idella were tested against, pathogenic bacteria viz, K.
pneumonia, V. cholerae, S. typhi, E. coli, P. aeruginosa
and five pathogenic fungi viz, Mucor globosus, Rhizopus
arrhizus, Candida albicans, Aspergillus flavus,
Aspergillus niger. The activity was measured in terms of
zone of inhibition in mm.
Antibacterial effect of mucus from surface feeders
and column feeders
The inhibition effects of mucus of C. catla, H. molitrix
against five pathogenic bacterial strains are given in
Table 1 and the zone of inhibition by the mucus of L.
rohita, C. idella are given in Table 2. The zone of
inhibition values of mucus were compared with control
(Ciproflaxin) and the observed values are tabulated in
Tables 1 and 2, respectively.
The mucus of C. catla showed more effect in controlling
the growth of gram-negative bacteria Salmonella typhi
with an inhibition zone of 32 mm in diameter which is
more than the control (Figure 3). Next to S. typhi, the
mucus of C. catla showed a better effect on P.
aeruginosa having an inhibition zone of 29 mm in
diameter (Figure 5). That was followed by the K.
pneumonia with an inhibition zone of 25 mm in diameter
(Figure 1). Among the five gram-negative bacteria tested
V. cholerae and E. coli showed very less sensitivity to the
mucus of C. catla with an inhibition zone of 21 and 23
mm in diameter (Figures 2 and 4).
The mucus of H. molitrix showed more effect in
controlling the growth of K. pneumonia and P. aeruginosa
with an inhibition zone of 22 and 22 mm in diameter
(Figures 1 and 5). Moderate effect was observed in
controlling the growth of V. cholerae with a zone of
inhibition is 20 mm in diameter (Figure 3). S. typhi (15
mm) and E. coli (16 mm) showed very less sensitivity to
the mucus of H. molitrix (Figures 3 and 4).
Whereas the mucus of L. rohita showed a strong effect
in controlling the growth of K. pneumonia with an
inhibition zone of 24 mm diameter (Figure 1). V. cholerae
and E. coli showed a better effect in the mucus of H.
molitrix with an inhibition zone of 21 mm in diameter
(Figures 2 and 4). Among the five bacteria tested S.
typhi and P. aeruginosa showed less sensitivity to the
mucus with an inhibition zone is 14 mm and 19 mm in
diameter (Figures 3 and 5).
The mucus of C. idella showed more effect in
controlling the growth of E. coli with an inhibition zone of
17 mm diameter (Figure 4). The moderate effect was
observed in controlling the growth of S. typhi (12 mm)
and P. aeruginosa (15 mm) by the mucus of C. idella.
Balasubramanian et al. 5113
Figure 1. K. pneumonia antibacterial activity of fish skin mucus.
Figure 2. Vibrio cholera Antibacterial activity of fish skin mucus.
Among these, the K. pneumonia and V. cholerae showed
very less sensitivity to the mucus of C. idella with an
inhibition zone of 7 mm diameter (Figures 1 and 2).
The antibacterial activity of control Ciproflaxin showed
maximum activity in three bacteria and some bacteria it
showed less activity than the mucus sample.
Antifungal effect of mucus
The effect of mucus from C. catla, H. molitrix against five
pathogenic fungal strains are given in Table 3 and the
zone of inhibition by the mucus of L. rohita, C. idella are
given in Table 4. The zone of inhibition values of control
(Ketoconazole) are tabulated in Tables 3 and 4,
respectively. The mucus of C. catla showed a maximum
effect in controlling the growth of A. flavus with an
inhibition zone of 17 mm diameter which is less than the
control (19 mm) (Figure 9). Next to this, the Mucor
globosus (16 mm) and R. arrhizus (16 mm) have more
zone of inhibition (Figure 6 and Figure 7). Whereas as
the mucus of C. catla has less effect in controlling the
growth of C. albicans (14 mm) and A. niger (9 mm)
(Figures 8 and 10). Likewise the mucus collected from H.
molitrix has highest effect in controlling the growth of A.
flavus with an inhibition zone is 17 mm (Figure 9). On the
Figure 2. Vibrio cholerae
5114 Afr. J. Microbiol. Res.
Figure 3. Salmonella typhi Antibacterial activity of fish
skin mucus.
Figure 4. Escherichia coli Antibacterial activity of fish
skin mucus.
contrary there is no effect in controlling the growth of
Rhizopus sp and C. albicans. (Figures 7 and 8). The
mucus of H. molitrix shows the moderate effect in
controlling the growth of Mucor globosus (14 mm) and A.
niger (8 mm) (Figures 6 and 10).
L. rohita a column feeder showed more effect in
controlling the growth of A. flavus (17 mm). The mucus
of L. rohita has very less sensitivity against the growth of
M. globosus and R. arrhizus (14 mm) (Figures 6 and 7).
But the mucus of L. rohita has the better effect in
controlling the growth of C. albicans (15 mm) and A. niger
(15 mm) (Figures 8 and 10).
The mucus of C. idella shows the highest activity
against A. flavus with an inhibition zone of 16 mm in
diameter (Figure 9). Next to A. flavus the mucus shows
better effect in controlling the growth of M. globosus (15
mm), R. arrhizus (15 mm) and C. albicans (13 mm) in
diameter (Figures 6, 7 and 8). But it failed to control the
growth of A. niger (Figure 10).
The antifungal activity of control Ketoconazole showed
a variety of activity against M. globosus (16 mm), R.
arrhizus (15 mm), C. albicans (17 mm), A. flavus (19 mm)
Figure 3. Salmonella typhi
Figure 4. Escherichia coli
Balasubramanian et al. 5115
Figure 5. Pseudomonas aeruginosa Antibacterial
activity of fish skin mucus. Co Control, C Catla, R
Rohu, S - Silver carp, G - Grass carp.
Table 3. Antifungal activity of skin mucus from Catla and Silver carp.
SNo
Name of the Fungal Pathogens
Zone of Inhibition (in mm)
Control
(Ketoconazole) (in mm)
Catla
Silver carp
1
M. globosus
16mm
14
16
2
R. arrhizus
16
-----
15
3
C. albicans
14
-----
17
4
A. flavus
17
17
19
5
A. niger
9
8
11
Table 4. Antifungal activity of skin mucus from Rohu and Grass carp.
SN
Name of the Fungal Pathogens
Zone of Inhibition (in mm)
Control
(Ketoconazole) (in mm)
Rohu
Grass carp
1
M. globosus
14
15
16
2
R. arrhizus
14
15
15
3
C. albicans
15
13
17
4
A. flavus
17
16
19
5
A. niger
15
----
11
and A. niger (11 mm), respectively.
DISCUSSION
The epithelial surfaces of fish, such as the skin, gills and
the alimentary tract provide first contact with potential
pathogens. The biological interface between fish and
their aqueous environment consists of a mucus layer
composing of biochemically-diverse secretions from
epidermal and epithelial cells (Ellis, 1999). This layer is
thought to act as a lubricant to have a mechanical
protective function, to be involved in osmoregulation and
play a possible role in immune system of fish. Fish tissue
and body fluids contain naturally occurring proteins or
glycoproteins of non-immunoglobulin nature that react
with a diverse array of environmental antigens and may
confer an undefined degree of natural immunity to fish.
Antimicrobial peptides are among the earliest developed
molecular effectors of innate immunity and are significant
Figure 5. Pseudomonas aeruginosa
5116 Afr. J. Microbiol. Res.
Figure 6. Mucor globosus Co Control, C Catla, R Rohu,
S - Silver carp, G - Grass carp.
Figure 7. Rhizopus arrhizus Co Control, C Catla, R
Rohu, S - Silver carp, G - Grass carp.
in the first line of host defense response of diverse
species.
Most antimicrobial peptides found through out the
animal and plant kingdom are small, functionally
specialized peptides (Boman, 1995). Several
endogenous peptides with antimicrobial activity from fish,
especially from the skin and skin mucus are reported
(Park et al., 1997). Endogenous peptides play an
important role in fish defense, possess broad spectrum of
antimicrobial activity against bacteria, yeast and fungi.
The epidermic and the epithelial mucus secretions act as
biological barriers between fish and the potential
Figure 6. Mucor globosus
Figure 7. Rhizopus arrhizus
Balasubramanian et al. 5117
Figure 8. Candida albicans Co Control, C Catla, R
Rohu, S - Silver carp, G - Grass carp.
Figure 9. Aspergillus flavus Co Control, C Catla, R Rohu,
S - Silver carp, G - Grass carp.
pathogens of their environment (Shephard, 1993). Group
of researchers suggest that the epidermal mucus acts as
a first line of defense against pathogens and therefore
may offer a potential source of novel antimicrobial
compounds (Ellis, 2001; Fouz et al., 1990; Grinde et al.,
1988; Nagashima et al., 2001; Sarmasik, 2002).
The mucus producing cells in epidermal and epithelial
layers had been reported to differ between fish species
and therefore could influence the mucus composition.
Furthermore, the biochemical substances of mucus have
been showed to differ depending on the ecological and
physiological condition (Subramanian et al., 2008). In the
present study also the mucus secreted by fishes are
having strong resistance to the microbes. The mucus
collected from all the four fishes show vary activity
against the tested bacteria.
Figure 8. Candida albicans
Figure 9. Aspergillus flavus
5118 Afr. J. Microbiol. Res.
Figure 10. Aspergillus niger Co Control, C Catla, R
Rohu, S - Silver carp, G - Grass carp.
Amphipathic α-helical peptides, such as dermaseptin,
ceratotoxin and magainin bind with anionic
phospholipids-rich membranes and dissolve them like
detergents (Pouny et al., 1992; Shai, 1995). These
peptides are known to exert action by binding to the
surface of the microbial membranes and causing a lysis
of the intracellular contents. Our present study was also
supported by the above studies in showing the
antibacterial activity.
Fish contain serum and cellular interferon which
possess anti-viral proteins, enzymes- inhibitors (e.g. α-
macroglobulin and other β-globulins) that inhibit the extra
cellular proteases secreted by pathogens (Alexander and
Ingram, 1992). They added that number of relatively
specific lytic molecules, like hydrolase enzymes
(Lysozyme, Chinase and Chitobiase) act on fungi and
bacteria. Fish also contain lectins possess antifungal and
antibacterial activities. Mucus contain several proteases
(serine proteases, cysteine proteases, metalloproteases
and trypsin (like proteases) having strong antibacterial
activity (Fast et al., 2002). The mechanism by which
antimicrobial substance kill microbes are still unclear, but
it is currently thought that different peptides employ
different strategies. These include the fatal depolarization
of the cell membrane (Westerhoff et al., 1989), the
formation of pores and subsequent leakage of the cell
contents (Yang et al., 2000) or the damaging of critical
intracellular targets after internalization of the peptide
(Kargol et al., 2001).
The antimicrobial substance present in the mucus may
function either in the cytoplasm against intracellular
pathogens or extracellularly through release to mucosal
surfaces after infection-induced cell lysis or apoptosis.
Few antimicrobial agents structurally identified in the
mucus of bony fishes are proteins. It has been proposed
that these compounds bind to and essentially dissolve
cellular membrane (Ebran et al., 1999; Zasloff, 2002).
The data of present study indicate that the antimicrobial
activity of the fish mucus may be due to the presence of
the above said substances. The mode of action of
mucus is yet to be determined but studies have proposed
various killing mechanisms for fish derived AMPs such as
cytoplasmic membrane disruption, pore or channel
formation (Syvitski et al., 2005) and inhibition of cell wall
and nucleic acid synthesis (Partzykat et al., 2002;
Brogden, 2005).
In the present study, variation in their antimicrobial
activity was observed among the fish mucus. This may
be due to the variation in the relative levels of lysozyme,
alkaline phosphatase, cathepsin B and proteases of the
epidermal mucus of all fish species (Subramanian et al.,
2007).
Both the indigenous and exotic fish species have the
activity against the bacterial pathogens, whereas some
fungal pathogens were not controlled by the mucus of
exotic fishes. But the mucus of indigenous fishes controls
the tested fungal pathogens. Native fish species
(indigenous) thrives better in prevalent conditions in
controlling the mosquitoes than exotic fishes (Chandra et
al., 2008). Falling in line with the above observation, the
indigenous fish species such as C. catla and L. rohita
show higher antimicrobial activity than that of the exotic
fish species such as H. molitrix and C. idella. This is the
first report on the antimicrobial activity of skin mucus of
Figure 10. Aspergillus niger
cultivable indigenous fishes of India. Moreover the mucus
of fish possesses antimicrobial agents which could be
used to formulate new drugs for the therapy of infectious
diseases caused by pathogenic and opportunistic
microorganisms. These properties of mucus suggest that
it may be beneficial in aquaculture and human health-
related applications. Further studies are needed to isolate
the bioactive compounds (antimicrobial substances) from
the mucus of these cultivable fish species and the
mechanism of antimicrobial action.
AKNOWLEDGEMENTS
Authors thank the authorities of Annamalai University,
and the Head of the Department of Zoology for providing
the facilities to carry out this study.
REFERENCES
Agarwal SK, Banerjee TK, Mittal AK (1979). Physiological adaptation in
relation to hyperosmotic stress in the epidermis of a freshwater
teleost Barbus sophor (Cypriniformes: Cyprinidae) a histochemical
study. Z. Mikrosk. Anat. Forsch., 93: 51-64.
Agosta W (1996). Bombardier beetles and fever trees: a close-up look
at chemical warfare and signals in animals and plants. Addison-
Wesley Publishing Company, New York. P. 224.
Alexander JB, Ingram GA (1992). Non cellular nonspecific defense
mechanisms of fish. Ann. Rev. Fish Dis., 2: 249-279.
Austin B, McIntosh D (1988). Natural antibacterial compounds on the
surface of rainbow trout. J. Fish Dis., 11: 275-277.
Bauer AW, Kirby WMM, Sherris JC, Turck M (1996). Antibiotic
susceptibility testing by a standardized single disc method. Am. J.
Clin. Pathol., 45: 493-496.
Boman HG (1995). Peptide antibiotics and their role in innate immunity.
Ann. Rev. Immunol., 13: 61-92.
Brogden KA (2005). Antimicrobial peptides: pore formers or metabolic
inhibitors in bacteria. Nat. Rev. Microbiol., 3(3): 238-250.
Chandra G, Bhattacharjee I, Chatterjee SN, Ghosh A (2008). Mosquito
control by larvivorous fish. Indian J. Med. Res., 127: 13-27.
Cole AM, Weis P, Diamond G (1997). Isolation and characterization of
pleurocidin, an antimicrobial peptide in the skin secretions of winter
flounder. J. Biol. Chem., 272: 12008-12013.
Costa EM, Marques JGW (2000). Faunistic resources used as
medicines by artisanal fishermen from Siribinha Beach, State of
Bahia, Brazil. J. Ethnobiol., 20: 93-109.
Dhanaraj M, Haniffa M, Arun A, Singh SV, Muthu RC, Manikandaraja
D, Milton JM (2009). Antibacterial activity of skin and intestinal mucus
of five different freshwater fish species viz., Channa striatus, C.
micropeltes, C. marulius, C. punctatus and C. gachua. Malay. J. Sci.,
28(3): 257-262.
Ebran N, Julien S, Orange N, Saglio P, Lemaitre C, Molle G (1999).
Pore forming properties and antibacterial activity of proteins extracted
from epidermal mucus of fish. Comp. Biochem. Physiol., 2: 181-189.
Ellis A (1999). Immunity to bacteria in fish. Fish Shellfish Immunol., 9:
291-308.
Ellis AE (1974). Non-specific defense mechanisms in fish and their role
in disease processes. Dev. Biol. Stand., 49: 337-352.
Ellis AE (2001). The immunology of teleosts, In: Roberts RJ (Ed), Fish
Pathology, 3rd edition. Elsevier, New York. pp. 133-150.
Fast MD, Sims DE, Burka JF, Mustafa A, Ross NW (2002). Skin
morphology and humoral non-specific defense parameters of mucus
and plasma in rainbow trout, coho and Atlantic salmon. Comp.
Biochem. Physiol. Mol. Integr. Physiol., 132: 645-657.
Fletcher T (1978). Defense mechanisms in fish. In: Malins D, Sargent J
(Eds.). Biochemical and biophysical perspectives in marine biology.
Balasubramanian et al. 5119
Academic Press, London. pp. 189-222.
Fouz B, Devesa S, Gravningen K, Barja JL, Tranzo AE (1990).
Antibacterial action of the mucus of the turbot. Bull. Eur. Assoc. Fish
Pathol., 10: 56-59.
Grinde B, Jolles J, Jolles P (1988). Purification and characterization of
two lysozymes from rainbow trout (Salmo gairdneri). Eur. J.
Biochem., 173: 269-273.
Hellio C, Pons AM, Beaupoil C, Bourgougnon N, Gal YIE (2002).
Antibacterial, antifungal and cytotoxic activities of extracts from fish
epidermis and epidermal mucus. Int. J. Antimicrob. Agents, 20(3):
214-219.
Ingram GA (1980). Substances involved in the natural resistance of fish
to infection-a review. J. Fish Biol., 16: 23-60.
Kimbrell DA, Beutler B (2001). The evolution and genetics of innate
immunity. Nat. Rev. Genet., 2: 256-267.
Knouft JH, Page LM, Plewa MJ (2003). Antimicrobial egg cleaning by
the fringed darter (Perciformes: Percidae: Etheostoma
crossopterum): Implications of a novel component of parental care in
fishes. Lond. Biol. Sci., 270: 2405-2411.
Kragol G, Lovas S, Varadi G, Condie BA, Hoffmann R, Otvos L Jr
(2001). The antibacterial peptide pyrrhocorin inhibits the ATPase
actions of Dnak and prevents chaperone-assisted folding.
Biochemistry, 40(10): 3016-3026.
Kunin WK, Lawton JH (1996). Does biodiversity matter? Evaluating the
case for conserving species. In Gaston KJ (Ed) Biodiversity: A
Biology of numbers and differences, Oxford: Blackwell Sci., 283-308.
Kuppulakshmi C, Prakash M, Gunasekaran G, Manimegala G, Sarojini
S (2008). Antibacterial properties of fish mucus from Channa
punctatus and Cirrhinus mrigala. Eur. Rev. Med. Pharmacol. Sci.,
12: 149-153.
Leistner L (1978). Hurdle effect and energy saving. In Downey WK (Ed.)
Food Quality and Nutrition. London: Appl. Sci. Pub., p. 553.
Mainous A, Pomeroy C (2001). Management of Antimicrobials in
Infectious Disease. Humana Press, New York. p. 349.
Manning MJ (1998). Immune defense systems. In: Blank KD, Pickering
AD (Eds), Biology of Farmed Fish. Academic Press, Sheffield. 180-
221.
Mat JAM, Mc Cullock R, Croft K (1994). Fatty acid and amino acid
composition in haruan as a potential role in wound healing. Gen.
Pharmacol., 25: 947-950.
Nagashima Y, Sendo A, Shimakura K, Kobayashi T, Kimura T, Fujii T
(2001). Antibacterial factors in skin mucus of rabbit fishes. J. Fish.
Biol., 58: 1761-1765.
Noga M, Magarinos B, Toranzo AE, Lamas J (1995). Sequential
pathology of experimental pasteurellosis in gilthead seabream sparus
aurata a light microscopic and electron microscopic study. Dis.
Aquat. Org., 21: 177-186.
Park CB, Lee JH, Park IY, Kim MS, Kim SC (1997). A novel
antimicrobial peptide from the loach Misgumus anguillicaudatus.
FEBS Lett., 411: 173-178.
Patrzykat A, Friedrich CL, Zhang L, Mendoza V, Hancock REW (2002).
Sublethal concentrations of pleurocidin-derived antimicrobial peptides
inhibit macromolecular synthesis in Escherichia coli. Antimicrob.
Agents Chemother., 46: 605-614.
Pouny Y, Rapaport D, Mor A, Nicolas P, Shai Y (1992). Interaction of
antimicrobial dermaseptin and its fluorescently labeled analogs with
phospholipid-membranes. Biochemistry, 31: 12416-12423.
Rottmann RW, Francis-Floyed R, Durborow R (1992). The role of stress
in fish disease. South. Reg. Aquac. Centre Publication, 3: 474.
Sarmasik A (2002). Antimicrobial peptides: a potential therapeutic
alternative for the treatment of fish diseases. Turk. J. Biol., 26: 201-
207.
Shai Y (1995). Molecular recognition between membrane-spanning
polypeptides. Trends Biochem. Sci., 20: 460-464.
Shephard KL (1993). Mucus on the epidermis of fish and its influence
on drug delivery. Adv. Drug. Deliv. Rev., 11: 403-417.
Subramanian S, Mackinnon SL, Ross NW (2007). A comparative study
on innate immune parameters in the epidermal mucus of various fish
species. Comp. Biochem. Physiol., 148B: 256-263.
Subramanian S, Ross NW, Mackinnon SL (2008). Comparison of
antimicrobial activity in the epidermal mucus extracts of fish. Comp.
Biochem. Physiol., 150 (B): 85-92.
5120 Afr. J. Microbiol. Res.
Syvitski R, Burton I, Mattatall NR, Douglas SE, Jakeman DL (2005).
Structural characterization of the antimicrobial peptide pleurocidin
from Winter flounder. Biochem., 44: 7282-7293.
Westerhoff HV, Juretic D, Hendler RW, Zasloff M (1989). Magainins
and the disruption of membrane- linked free-energy transduction.
Proc. Natl. Acad. Sci., USA. 86: 6597.
WHO (2002). Food safety and food borne illness. World Health
Organization Fact Sheet, Geneva. 237.
Yang JY, Shin SY, Lim SS, Hahm KS, Kim Y (2000). Structure and
bacterial cell selectivity of a fish derived antimicrobial peptide,
pleurocidin. J. Microbiol. Biotech., 16: 880-888.
Zasloff M (2002). Antimicrobial peptides of multicultural organisms.
Nature, 415: 389-395.
Zuchelkowski EM, Lantz RC, Hinton DE (1981). Effects of acid-stress
on epidermal mucus cells of the brown bullhead-Ictalurus nebulosus
(Leseur): A morphometric study. Anat. Rec., 200: 33-39.
... Los peces fueron introducidos en las peceras teniendo cuidado de no mezclar el agua de las bolsas con el agua de la pecera pues al momento de ser transportados, los niveles de amoníaco pueden aumentar por el estrés y en consecuencia excretan en mayor cantidad. (2019) 5(1): [3][4][5][6][7][8][9][10][11] Alimentación Antes de la realización de las pruebas de toxicidad se les alimentó a los alevinos de gamitana con alimento extrusado inicio de Purigamitana, que se les suministró dos veces al día, por la mañanas y al final del día. ...
... Esta secreción de mucus puede deberse al posible efecto irritante del mercurio, siendo el mucus una respuesta adaptativa para la protección mecánica de la superficie del pez. Esta respuesta ha sido descrita en la exposición a otros contaminantes, así como parásitos y bacterias, sin embargo, el incremento o disminución también depende de cambios en la calidad de agua: amonio disuelto, alcalinidad registrados por Balasubramanian et al. (9) Esteban (10) , Ferguson (11) el cual el presente estudio, no muestra similaridad de datos con los resultados de los autores mencionados. ...
... Revista de Investigación: Ciencia, Tecnología y Desarrollo(2019) 5(1):[3][4][5][6][7][8][9][10][11] ...
Article
Full-text available
En el presente se registra la concentración letal media (CL50) a 96 horas del mercurio en gamitana [Colossoma macropomum (Cuvier, 1818)]. Se calculó a través de una prueba estática de toxicidad aguda utilizando cloruro de mercurio (HgCl2) como agente letal. El experimento fue realizado el distrito de San Juan Bautista, Provincia de Maynas, Región Loreto (Perú), en condiciones controladas (28,85 ± 0,15 °C) y un fotoperiodo 12:12 (luz: oscuridad). Los alevinos (4 ± 1 g) fueron mantenidos en acuarios de vidrio con aireación constante, sin filtro y la alimentación fue suprimida 24 horas antes del inicio del experimento. Se emplearon 3 concentraciones de mercurio (Hg), con sus respectivas réplicas, incluyendo un grupo control. Las concentraciones fueron: 0,01, 0,1 y 1 mg Hg/L. Se realizó un análisis histopatológico con tres peces de cada tratamiento tomando muestras de branquias. Los especímenes expuestos a las concentraciones más bajas (0,01 y 0,1 mg Hg/L) mostraron hiperactividad, a diferencia de la concentración más alta (1 mg Hg/L) los cuales evidenciaron disminución de su actividad. El análisis histopatológico mostró anomalías en las branquias como hiperplasia interlamelar y vasculizaciones lipídicas respectivamente, en respuesta a procesos de detoxificación. El valor de la CL50-96 h fue estimado utilizando el programa TSK (Trimmed-Spearman-Karber) y presentó un valor de 0,23 mg HgCl2/L ± 0,15.
... Leclercia adecarboxylata, Candida glabrata and Candida parapsilosis were found to be most susceptible, whereas Bacillus cereus was found to be least susceptible to the crude protein extract (Table 1). These results are similar to findings of earlier studies by various authors who observed that piscine mucus is a good source of antimicrobial products which show strong antibacterial activity in several fishes (Balasubramanian et al., 2012;Prakash et al., 2013;Nurtamin et al., 2016;Kumari et al., 2019). These AMPs may act as the primary defense against invading pathogens in these organisms. ...
... + + + = weak activity (zone of inhibition 1-6 mm); + + = moderate activity (zone of inhibition 7-12 mm);+++ = high activity (zone of inhibition 13 mm and above) layer of fish contains a variety of substances such as lectin, lysozyme, proteases (serine proteases, cysteine proteases, metalloproteases and trypsin) and protein, all of which have antibacterial and antifungal properties and serve as the first line of defense against invading germs (Nurtamin et al., 2016). Protein derived from fish epidermal mucus has been shown to work as an antibacterial and antifungal by forming pores in microbe cell membranes or by lethal depolarization of the cell membrane and subsequent release of the cell contents (Balasubramanian et al., 2012). The data of the present study indicate that the antimicrobial activity of the crude mucus extract may be due to the presence of the above mentioned antimicrobial substances. ...
Article
Full-text available
Fish epidermis is rich in different pharmacologically active substances, most of which play a crucial role in immunity. In the current study, β-defensin-like protein 1 with high in vitro antimicrobial activity was isolated and characterized from crude epidermal mucus extract of common carp, Cyprinus carpio L. The crude mucus was screened for antimicrobial activity against five bacterial and four fungal pathogens. Crude mucus exhibited varied antimicrobial activity against all the used pathogens. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of crude mucus extract revealed multiple prominent bands with molecular weights corresponding to 6.9 kDa, 14.5 kDa, 24 kDa, 27 kDa and 48 kDa. Using Sephadex G-50 gel filtration liquid chromatography in conjunction with mass spectroscopy (LC/MS), a single peak with a molecular weight of 6908 Da was isolated and characterized. This peptide showed potent antimicrobial activity against all the five bacterial and four fungal strains used. Leclercia adecarboxylata and Enterobacter kobei were most susceptible with minimum inhibition concentration (MIC) value of 0.017 mg/mL, while Aeromonas sobria was least susceptible with an MIC of 2.24 mg/mL. Among the fungal pathogens, Candida glabrata was most susceptible with MIC value of 0.14 mg/mL, while Aspergillus sp. was least susceptible with MIC value of 4.48 mg/mL. The activity was further confirmed by the time kill assay. The antimicrobial peptide sequence determined from mass spectra was “PQSILVLLVLVVLALHCKENEAVSFPWSCASLSGVCRQGVCLPSELYFGPLGCGKGFLCCVSHF”, which consisted of 64 amino acids. Protein Basic Local Alignment Search Tool (BLASTP) of this sequence revealed 100% homology with the β-defensin-like protein 1, which is the first report of this antimicrobial peptide from epidermal mucus of C. carpio from Kashmir waters.
... Presence of basic peptide might be the reason behind higher antifungal action exhibited by acidic mucus extracts of all fishes. Balasubramanian et al. (2011) studied the antifungal effect of epidermal mucus of C. catla against A. niger (9 mm), A. flavus (17 mm) and C. albicans (14 mm). However, they didn't study the acidic and organic mucus extract effect. ...
... (acidic and organic) of all experimental fishes showed ZOIs against C. albicans.Uthayakumar et al. (2012) observed antifungal activity in both the acidic and organic mucus extracts of Mastacembulus armatus, in our work, both acidic and organic mucus extracts of all experimental fishes exhibited higher ZOIs against above mentioned fungal pathogens.Balasubramanian et al. (2011) too reported the antifungal effect of mucus of C. catla, L. rohita, C. mrigala, H. molitrix, Mugil cephalus and C. punctatus against five pathogenic strains. Out of which three were common to our study. Against common fungal pathogens ZOIs values obtained in our results were higher than those reported by them. Acidic mucus extracts of a ...
Article
Full-text available
The present work aimed at assessing the antifungal properties of fish epidermal mucus of fresh water fish species viz., Catla catla, Cyperinus carpio and Heteropneustes fossilis against seven pathogenic fungal strains : Aspergillus niger, A. clavatus, A. flavus, Candida albicans, C. tropicalis, C. auris and Mucor ramosissimus. Disk diffusion method was used to analyze the antifungal action of acidic and organic mucus extracts of all selected fishes. Zone of inhibition (ZOI) was also recorded to compare the antifungal effect of these fishes and antibiotic fluconazole against the fungal pathogens. Minimum inhibitory concentration (MIC) was calculated for each pathogenic fungal strain. A potent antifungal effect has been noticed in both acidic and organic mucus extracts of all experimental fishes, even higher than fluconazole in some cases. These results support the presence of antifungal components in fish epidermal mucus, which could be used as an alternative to commercial antibiotics in humans as well as animals.
... Although, with the changing climate along with the increasing accumulation of unwanted substances in the water body with due course of time has put the developmental process of the fishes become limited and creates several problems. It is believed that several organisms generally of pathogenic nature have affected the fish health system (Balasubramanian et al., 2012) [2] . This has resulted diseases in fish and cause the major economic losses in the field of aquaculture (Faruk and Anka, 2017) [3] . ...
... Although, with the changing climate along with the increasing accumulation of unwanted substances in the water body with due course of time has put the developmental process of the fishes become limited and creates several problems. It is believed that several organisms generally of pathogenic nature have affected the fish health system (Balasubramanian et al., 2012) [2] . This has resulted diseases in fish and cause the major economic losses in the field of aquaculture (Faruk and Anka, 2017) [3] . ...
Article
Full-text available
The present investigation was conducted to assess the antibacterial activity of integumentary extract of freshwater fish species viz., Singhi (Heteropneustes fossilis) and Mrigal (Cirrhinus mrigala) and neem (Azadirachta indica) extracts (leaves and bark) against the selected microbes namely Aeromonas hyprophila and Staphylococcus aureus. Disc diffusion method was employed to determine the antibacterial activity of different extracts. In this study Heteropneutes fossilis integumentary secretions extract demonstrated greater inhibitory ability than Cirrhinus mrigala. It was also observed that Heteropneutes fossilis integumentary extract have more inhibitory effect against Aeromonas hyprophila (22±2.05) than Staphylococcus aureus (18±1.56). While, the ethanol extract of neem leaves was observed to possess higher antibacterial activity than that of neem bark extract. Interestingly, the neem leaves extract had shown more inhibitory activity against the Staphylococcus aureus (13±1.76) as compared to Aeromonas hyprophila (12±1.88). The study highlights the importance of fish integumentary and neem extracts as potential antibacterial agents.
... Aspergillus spores are stored in the mucus of fishes. Aspergillus niger and A. flavus spores were found in the mucus of H. molitrix (Balasubramanian et al., 2012). The spores might become pathogenic, when these spores are established in skin and sometime invade in epidermis. ...
Article
Full-text available
Fungal diseases are very common in freshwater fishes. Aspergillosis is a fungal disease of fish. This study was designed to examine a fungal infection in silver carp, Hypophthalmichthys molitrix. The infected fish showed clinical signs such as: eroded gills, damaged fins and lesions all over the body. The fish specimens showed mild to severe infection. The infection caused by fungus was confirmed by isolating the pathogenic fungus from affected skin, gills, fins, heart, liver, kidney and intestine of fish and culturing it on four different culture media; Malt extract agar (MEA), Corn meal agar (CMA), Sabouraud dextrose agar (SDA) and Potato dextrose agar (PDA). The inoculated culture plates were incubated for 5-8 days at 28-32 oC. The fungal growth in the form of colonies of different shapes and colour appeared in agar plates. Four Aspergillus spp.; Aspergillus terreus (8.40%), A. flavus (17.06%), A. fumigatus (24.02%) and A. niger (50.52%) were isolated from fish. Aspergillus niger showed high infection and it was recorded on all 200 fish samples. Fins were the most affected parts with 39.10% infection. Intestine was the least affected part with 6.59% infection. The major reason of aspergillosis in silver carp is the use of unhealthy and unhygienic feed given to silver carp reared in earthern ponds. Due to aspergillosis fish may not be recommended for human consumption. If proper health management practices are adopted on fish rearing
... Several studies have revealed that the fish skin mucus has strong anti-bacterial and/or bacteriostatic activities against a broad range of microbial pathogens [18][19][20][21]. However, and despite the important role of skin mucus in fish defence against pathogens, the study of the mucosal immune response during bacterial infection or after bacterial challenge remains limited [3,6]. ...
Article
Most pathogens start the process of infection at the mucosal surfaces and therefore the mucosal immune response plays an essential role in the course of the infection. Due to the Senegalese sole (Solea senegalensis Kaup) condition of flatfish, the present comparative study aimed to analyse several immune-related enzymes as well as the bactericidal activity in the skin mucus from ocular and blind sides. For this purpose, Senegalese sole juveniles were bath challenged with a sub-lethal dose of Tenacibaculum maritimum for 24 h and sampled at 1, 2 and 3 weeks. The haematological profile and immune-related parameters were also measured in plasma in order to evaluate the systemic immune response after T. maritimum challenge. Results from this study showed that most parameters tested increased in skin mucus of bath challenged fish compared to unchallenged ones. In contrast, the sub-lethal dose tested did not influence the haematological profile including peripheral numbers the different leucocyte types. No variations were observed in plasma lysozyme, peroxidase, protease and haemolytic complement activities between unchallenged and bath challenged fish. This study suggests that the studied innate immune-related molecules are constitutively present in both skin mucus sides but at different levels. Interestingly, the levels of most parameters measured were higher on the ocular side than on the blind side, possibly due to the higher exposure to invasion by waterborne microorganisms on this side. Therefore, the present study brings some insights regarding local immune responses after bacterial challenge in skin mucus from the ocular and blind sides in one of the most valuable flatfish species in southern Europe.
... Furthermore, it was also demonstrated that skin mucus plays a major role in preventing the colonization by parasites, bacteria and fungi [14,15]. In fact, antibacterial activity against a broad range of infectious pathogens has been described in epidermal fish mucus [16,17]. ...
Article
The biological activities observed upon envenomation by Scorpaena plumieri could be linked to both the venom and the skin mucus. Through a proteomic/functional approach we analyzed protein composition and biological activities of the venom and skin mucus. We identified 885 proteins: 722 in the Venomous Apparatus extracts (Sp-VAe) and 391 in the Skin Mucus extract (Sp-SMe), with 494 found exclusively in Sp-VAe, being named S. plumieri Venom Proteins (Sp-VP), while 228 were found in both extracts. The majority of the many proteins identified were not directly related to the biological activities reported here. Nevertheless, some were classified as toxins/potentially interesting molecules: lectins, proteases and protease inhibitors were detected in both extracts, while the pore-forming toxin and hyaluronidase were associated with Sp-VP. Proteolytic and anti-microbial activities were linked to both extracts, while the main toxic activities - cardiovascular, inflammatory, hemolytic and nociceptive - were elicited only by Sp-VAe. Our study provided a clear picture on the composition of the skin mucus and the venom. We also show that the classic effects observed upon envenomation are produced by molecules from the venomous gland. Our results add to the growing catalogue of scorpaeniform fish venoms and their skin mucus proteins. Significance: In this study a large number of proteins - including classical and non-classical toxins - were identified in the venomous apparatus and the skin mucus extracts of the Scorpaena plumieri fish through shotgun proteomic approach. It was shown that the toxic effects observed upon envenomation are elicited by molecules originated from the venomous gland. These results add to the growing catalogue of scorpaeniform fish venoms and their skin mucus proteins - so scarcely explored when compared to the venoms and bioactive components of terrestrial animals. Data are available via ProteomeXchange with identifier PXD009983.
Article
The current study was designed to investigate the role of a commercial probiotic containing equal proportions (1:1) of Bacillus subtilis and B. licheniformis spores (1.6 × 1012 CFU/kg; DiPro Aqua) on the growth, immune response, and intestinal morphology of Rainbow Trout Oncorhynchus mykiss. A total of 168 Rainbow Trout fry were randomly divided into four groups and were fed diets with different doses of DiPro Aqua (control: 0 CFU/kg; treatment 1 [T1]: 8 × 108 CFU/kg; T2: 16 × 108 CFU/kg; T3: 24 × 108 CFU/kg) for 56 d. The highest body weight gain and specific growth rate were obtained in the T2 and T3 groups. In addition, the highest feed conversion ratio was measured in the control group. The results showed that the serum total immunoglobulins and total protein content were increased in fish that were fed the T2 and T3 diets compared to those that received the T1 and control diets (P < 0.05). The highest alternative complement pathway hemolytic activity was measured in T2 fish compared to the other groups. According to the antibacterial activity of the skin mucus samples against Yersinia ruckeri, dietary levels of DiPro Aqua improved the mucus bactericidal activity and the maximum effect was recorded in the T2 group. The dietary levels of the probiotic mixture, especially in T2, increased the villus length, villus width, and crypt depth within the distal intestine compared to those in the control group. In conclusion, the optimal dietary dose of DiPro Aqua to boost growth performance, immunity, and intestinal morphology in Rainbow Trout was 2.0 × 108 CFU/kg based on polynomial regression analysis.
Article
This research was directed to understand the bactericidal effect of epidermal mucus of two Asian cat fish species viz. Clarias batrachus and Heteropneustes fossilis. Epidermal mucus extracts (raw and diluted) of both cat fish species were tested against several Gram negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, A. hydrophila) and Gram positive bacterial strains (Bacillius cereus, Staphylococcus aureus, S. epidermidis) and antibacterial results were also compared with two standard antibiotics viz. amikacin and chloramphenicol used as positive control. An A. hydrophila challenge experiment was also performed on all selected test fish species to examine the change in the amount of mucus production and its bactericidal impact.. Both epidermal mucus extracts (raw and diluted) of all selected normal and bacterial challenged test objects showed potent bactericidal effect against all pathogenic bacterial strains taken under study. However, former was more effective than later. Also raw epidermal mucus extracts of both normal and bacterial challenged cat fish species exhibited significantly higher ZOI values against all selected microbial strains than diluted mucus extracts and antibiotic chloramphenicol. Hence, these outcomes have clearly revealed that this cost effective natural product acquired from fishes is the key component of their defensive system. Therefore, it could be utilized as a novel ‘antimicrobial’ in human as well as veterinary sector for combating against several bacterial diseases.
Article
Fishes counteract certain microbial attacks in water by producing antimicrobial proteins/peptides in their skin surface. The present study focused on screening the bactericidal activity of skin and skin mucus extracts of Catla catla and Channa striatus. The bactericidal activity was assessed against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus vulgaris, Aeromonas hydrophila, Staphylococcus aureus and Bacillus coagulans by disc diffusion method. The minimal inhibitory concentration was also determined. Protein profiles in skin and skin mucus extracts were analyzed by SDS-PAGE. Samples from both fishes showed antibacterial activity. Detailed analysis of individual protein and peptide would throw light on their medicinal importance to be used against pathogenic microbes.
Book
Optimal antimicrobial use is essential in this era of escalating antibiotic resistance. Clinicians, particularly those on the frontlines of care, need an understanding of the management of common infectious diseases and the appropriate use of antimicrobials in the context of resistant pathogens. In Management of Antimicrobials in Infectious Diseases, Arch Mainous, PhD and Claire Pomeroy, MD and a group of antimicrobial experts and experienced clinicians provide an eminently practical summary of the most effective evidence-based antimicrobial treatments encountered in both the hospital and outpatient settings. At the forefront of this book is the clinical impact of appropriate diagnosis and treatment, as well as an emphasis on the newer aspects of infectious disease management necessitated by the increasing problem of resistant pathogens. Further, the book provides useful information on major pathogens to help practicing clinicians not only diagnose but treat effectively infections and their concomitant complications. Multidisciplinary and highly practical, Management of Antimicrobials in Infectious Diseases offers busy clinicians, nurse practitioners, as well as residents and medical students a comprehensive and informed guide for management and treatment in the contemporary environment fraught with resistant pathogens.
Article
Pleurocidin, an α-helical cationic antimicrobial peptide, was isolacted from skin mucosa of winter flounder (Pleuronectes americanus). It had strong antimicrobial activities against Gram-positive and Gram-negative bacteria, but had very weak hemolytic activity. The Gly13,17→Ala analog (pleurocidin-AA) showed similar antibacterial activities, but had dramatically increased hemolytic activity. The bacterial cell selectivity of pleurocidin was confirmed through the membrane-disrupting and membrane-binding affinities using dye leakage, tryptophan fluorescence blue shift, and tryptophan quenching experiments. However, the non-cell-selective antimicrobial peptide, pleurocidin-AA, interacts strongly with both negatively charged and zwitterionic phospholipid membranes, the latter of which are the major constituents of the outer leaflet of erythrocytes. Circular dihroism spectra showed that pleurocidin-AA has much higher contents of α-helical conformation than pleurocidin. The tertiary structure determined by NMR spectroscopy showed that pleurocidin has a flexible structure between the long helix from Gly3 to Gly17 and the short helix from Gly17 to Leu25. Cell-selective antimicrobial peptide pleurocidin interacts strongly with negatively charged phospholipid membranes, which mimic bacterial membranes. Structural flexibility between the two helices may play a key role in bacterial cell selectivity of pleurocidin.