Rosamma, Philip; Kumar, S; Achuthankutty, C T(2006)
[+]
[-]
Abstract:
Aquaculture farms, particularly in Southeast Asia are
facing severe crisis due to increasing incidences of
White Spot Syndrome Virus (WSSV). Actinomycetes
have provided many important bioactive compounds of high prophylactic and therapeutic value and are
continually being screened for new compounds. In this
communication, the results of a study made to determine
the effectiveness of marine actinomycetes against the white spot disease in penaeid shrimps are presented.
Twenty-five isolates of actinomycetes were tested for
their ability to reduce infection due to WSSV among
cultured shrimps. When these actinomycetes were
made available as feed additives to the post-larvae of
the black tiger shrimp Penaeus monodon for two weeks and challenged with WSSV, the post challenge survival
showed variations from 11 to 83%. However, six
isolates have shown to be the most potential candidates
for further study.
Bright Singh, I S; Rosamma, Philip; Sudheer, N S(Springer, May 29, 2012)
[+]
[-]
Abstract:
White spot syndrome virus (WSSV), the most
contagious pathogen of cultured shrimp, causes mass
mortality, leading to huge economic loss to the shrimp
industry. The lack of effective therapeutic or prophylactic
measures has aggravated the situation, necessitating the
development of antiviral agents. With this objective, the
antiviral activity in the aqueous extract of a mangrove plant
Ceriops tagal in Penaeus monodon was evaluated. The
Ceriops tagal aqueous extract (CTAE) was non-toxic to
shrimps at 50 mg/ml when injected intramuscularly at a
dosage of 10 lL/animal (0.5 mg/animal) and showed a
protective effect against WSSV at 30 mg/ml when mixed
with WSSV suspension at a 1:1 ratio. When the extract was
administered along with the diet and the animals were
challenged orally, there was a dose-dependent increase in
survival, culminating in 100 % survival at a concentration
of 500 mg/kg body weight/day. Neither hypertrophied
nuclei nor the viral envelope protein VP28 could be demonstrated
in surviving shrimps using histology and indirect
immunofluorescence histochemistry (IIFH), respectively.
To elucidate the mode of action, the temporal expression of
WSSV genes and shrimp immune genes, including antimicrobial
peptides, was attempted. None of the viral genes
were found to be expressed in shrimps that were fed with
the extract and challenged or in those that were administered
CTAE-exposed WSSV. The overall results suggest
that the aqueous extract from C. tagal can protect
P. monodon from white spot syndrome virus infection.
Description:
Arch Virol (2012) 157:1665–1675
DOI 10.1007/s00705-012-1346-3
Bright Singh, I S; Vici, V; Sarita,G Bhat(Academic Press, March 10, 2000)
[+]
[-]
Abstract:
The fresh water prawn, Macrobrachium rosenbergii, has proven potential for use as an
aquaculture species (Hanson & Goodwin, 1997; Kurup, 1984). In India alone, culture of
this species of prawn in low saline areas requires about 200 million seed per year
(Kurup, 1984). In hatcheries poor survival rate has been associated with vibriosis at
di#erent stages of the larval cycle. Members of the family Vibrionaceae associated with
the larvae of M. rosenbergii were shown to be pathogenic under laboratory conditions
(Bhat et al., 2000, in press). Vibrios have been associated with mortality of penaeid
prawns by several workers (Aquacop, 1977; Hameed, 1993; Karunasagar et al., 1994).
Two methods have been suggested to protect both the larvae and juveniles from
vibriosis; one is the administration of bacterins prepared from pathogenic strains
(Itami et al., 1989, 1991; Adams, 1991; Song & Sung, 1990; Sung et al., 1991) and the
other is the utilization of yeast 1-3 and 1-6 glucans as immunostimulants for
enhancing the non-specific defense system (Sung et al., 1994; Song et al., 1997). In the
light of these observations it was hypothesised that bacterins and yeast glucans may
also be e#ective in protecting the larvae of M. rosenbergii from vibriosis as has been
achieved in the case of penaeids. To examine this hypothesis, the ability of bacterins
and an extracellular glucan-producing yeast to increase the overall survival and
metamorphosis of larvae in a hatchery, as well as to protect against an experimental
challenge under laboratory conditions, was evaluated
Description:
Fish & Shellfish Immunology (2000) 10, 559–563
doi:10.1006/fsim.2000.0278
Prajith, K K; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, December , 2011)
[+]
[-]
Abstract:
In India a study conducted by CIFE and CIBA (1997), concluded that
shrimp farming does more good than harm and it is not eco-unfriendly
(Krishnan and Birthal, 2002). Upsurge in coastal aquaculture activity
induced by high profitability is reported to have caused adverse impacts on
coastal ecosystems and social environments (Parthasarathy and Nirmala,
2000). The crustacean farming sector has received criticism for excessive
use of formulated feed containing high protein, of which around 50% gets
accumulated at the pond bottom as unconsumed (Avnimelech, 1999; Hari
et al., 2004, 2006). The wasted feeds undergo the process of degradation
and results in the release of toxic metabolites to the culture system.
Reduction of protein in the feed, manipulation and utilisation of natural
food in the culture system are the remedy for the above problems. But
before reducing the feed protein, it should be confirmed that the feed with
reduced protein is not affecting the growth and health of the cultured
animal. In the present study, biofloc technology is identified as one of the
innovative technologies for ensuring the ecological and environmental
Sustainability and examines the compatibility of BFT for the sustainable
aquaculture of giant prawn, M. rosenbergii. This thesis starts with a general introduction (Chapter-1), a brief review of the most relevant literature (Chapter-2), results of various experiments (Chapter-3-6), summary (Chapter-7) and recommendations and future research perspectives in the field of biofloc based aquaculture (Chapter – 8). The major objectives of this thesis are, to improve the ecological and economical sustainability of prawn farming by the applicationof BFT and to improve the nutrient utilisation in aquaculture systems.
Description:
School of Industrial Fisheries, Cochin University of Science and Technology
Ravi, Divakaran; Dr.Sivasankara Pillai, V N(Cochin University of Science and Technology, January 15, 2002)
[+]
[-]
Abstract:
The most common and conventional method for removing turbidity from
water is by coagulating with alum or iron salts, and settling the precipitate in
suitably designed clarifiers followed by filtration. But the sludge produced is
bulky, difficult to dewater and accumulates in the dumping grounds causing
environmental problems. Synthetic polymers such as polyacrylamide and
polyethyleneoxide have been investigated for their ability to remove turbidity.
They overcome many of the disadvantages of conventional methods, but are
cost—effective only when rapid flocculation and reduction in sludge volume are
demanded. Considering the aforementioned situation, it was felt that more easily
available and eco-friendly materials must be developed for removing turbidity
from water. The results of our studies in this direction are presented in this
thesis. The thesis comprises of nine chapters, with a common bibliography at
the end. Chapter 1 gives an introduction to the nature of turbidity and colour
usually present in water. Chapter 2 discusses the nature and availability of the
principal material used in these studies, namely chitosan. Chapters 3 to 8, which
deal with the actual experimental work, are further subdivided into (a)
introduction, (b) materials and methods, (c) results and discussion and (d)
conclusions. Chapter 9 summarises the entire work so as to put the results and
conclusions into proper perspective.
Description:
School
of Environmental Studies, Cochin University of Science and Technology,
Sini, T K; Dr. Mathew, P T(Central Institute of Fisheries Technology, December , 2007)
[+]
[-]
Abstract:
The present study aimed at the utlisation of microbial organisms for the
production of good quality chitin and chitosan. The three strains used for the
study were Lactobacillus plantarum, Lactobacililus brevis and Bacillus subtilis.
These strains were selected on the basis of their acid producing ability to reduce
the pH of the fermenting substrates to prevent spoilage and thus caused
demineralisation of the shell. Besides, the proteolytic enzymes in these strains
acted on proteinaceous covering of shrimp and thus caused deprotenisation of
shrimp shell waste. Thus the two processes involved in chitin production can be
affected to certain extent using bacterial fermentation of shrimp shell.Optimization parameters like fermentation period, quantity of inoculum,
type of sugar, concentration of sugar etc. for fermentation with three different
strains were studied. For these, parameters like pH, Total titrable acidity (TTA),
changes in sugar concentration, changes in microbial count, sensory changes
etc. were studied.Fermentation study with Lactobacillus plantarum was continued with 20%
w/v jaggery broth for 15 days. The inoculum prepared yislded a cell
concentration of approximately 108 CFU/ml. In the present study, lactic acid and
dilute hydrochloric acid were used for initial pH adjustment because; without
adjusting the initial pH, it took more than 5 hours for the lactic acid bacteria to
convert glucose to lactic acid and during this delay spoilage occurred due to
putrefying enzymes active at neutral or higher pH. During the fermentation study,
pH first decreased in correspondence with increase in TTA values. This showed
a clear indication of acid production by the strain. This trend continued till their
proteolytic activity showed an increasing trend. When the available sugar source
started depleting, proteolytic activity also decreased and pH increased. This was
clearly reflected in the sensory evaluation results. Lactic acid treated samples
showed greater extent of demineralization and deprotenisation at the end of
fermentation study than hydrochloric acid treated samples. It can be due to the
effect of strong hydrochloric acid on the initial microbial count, which directly
affects the fermentation process. At the end of fermentation, about 76.5% of ash was removed in lactic acid treated samples and 71.8% in hydrochloric acid
treated samples; 72.8% of proteins in lactic acid treated samples and 70.6% in
hydrochloric acid treated samples.The residual protein and ash in the fermented residue were reduced to
permissible limit by treatment with 0.8N HCI and 1M NaOH. Characteristics of
chitin like chitin content, ash content, protein content, % of N- acetylation etc.
were studied. Quality characteristics like viscosity, degree of deacetylation and
molecular weight of chitosan prepared were also compared. The chitosan
samples prepared from lactic acid treated showed high viscosity than HCI treated
samples. But degree of deacetylation is more in HCI treated samples than lactic
acid treated ones. Characteristics of protein liquor obtained like its biogenic
composition, amino acid composition, total volatile base nitrogen, alpha amino
nitrogen etc. also were studied to find out its suitability as animal feed
supplement.Optimization of fermentation parameters for Lactobacillus brevis
fermentation study was also conducted and parameters were standardized. Then
detailed fermentation study was done in 20%wlv jaggery broth for 17 days. Also
the effect of two different acid treatments (mild HCI and lactic acid) used for initial
pH adjustment on chitin production were also studied. In this study also trend of
changes in pH. changes in sugar concentration ,microbial count changes were
similar to Lactobacillus plantarum studies. At the end of fermentation, residual
protein in the samples were only 32.48% in HCI treated samples and 31.85% in
lactic acid treated samples. The residual ash content was about 33.68% in HCI
treated ones and 32.52% in lactic acid treated ones. The fermented residue was
converted to chitin with good characteristics by treatment with 1.2MNaOH and
1NHCI.Characteristics of chitin samples prepared were studied and extent of Nacetylation
was about 84% in HCI treated chitin and 85%in lactic acid treated
ones assessed from FTIR spectrum. Chitosan was prepared from these samples
by usual chemical method and its extent of solubility, degree of deacetylation,
viscosity and molecular weight etc were studied. The values of viscosity and
molecular weight of the samples prepared were comparatively less than the
chitosan prepared by Lactobacillus plantarum fermentation. Characteristics of protein liquor obtained were analyzed to determine its quality and is suitability as
animal feed supplement.Another strain used for the study was Bacillus subtilis and fermentation
was carried out in 20%w/v jaggery broth for 15 days. It was found that Bacillus
subtilis was more efficient than other Lactobacillus species for deprotenisation
and demineralization. This was mainly due to the difference in the proteolytic
nature of the strains. About 84% of protein and 72% of ash were removed at the
end of fermentation. Considering the statistical significance (P<O.05) in the
extent of demineralization and deproteinisation, we have taken 0.8N HCI for the
demineralization study and 0.6M NaOH for deprotenisation study. Properties of
chitin and chitosan prepared were analyzed and studied.
Sony, George; Dr.V P N Nampoori(Cochin University of Science & Technology, September , 2011)
[+]
[-]
Abstract:
The present thesis report the results obtained from the studies carried out on the
laser blow off plasma (LBO) from LiF-C (Lithium Fluoride with Carbon) thin film
target, which is of particular importance in Tokamak plasma diagnostics. Keeping
in view of its significance, plasma generated by the irradiation of thin film target by
nanosecond laser pulses from an Nd:YAG laser over the thin film target has been
characterized by fast photography using intensified CCD. In comparison to other
diagnostic techniques, imaging studies provide better understanding of plasma
geometry (size, shape, divergence etc) and structural formations inside the plume
during different stages of expansion.
Description:
International School of Photonics,Cochin University of Science and Technology
Achamma, Kurian; Bindhu, C V; Harilal, S S; Issac, Riju C; Nampoori, V P N; Vallabhan, C P G(Pramana, November , 1994)
[+]
[-]
Abstract:
A simple method based on laser beam deflection to study the variation of diffusion
coefficient with concentration in a solution is presented. When a properly fanned out laser
beam is passed through a rectangular cell filled with solution having concentration gradient,
the emergent beam traces out a curved pattern on a screen. By taking measurements on the
pattern at different concentrations, the variation of diffusion coefficient with concentration can
be determined.
Shalin Saleem; Dr.Sanil Kumar, K V(Cochin University Of Science And Technology, October 16, 2012)
[+]
[-]
Abstract:
Satellite remote sensing is being effectively used in monitoring the ocean
surface and its overlying atmosphere. Technical growth in the field of satellite sensors
has made satellite measurement an inevitable part of oceanographic and atmospheric
research. Among the ocean observing sensors, ocean colour sensors make use of
visible band of electromagnetic spectrum (shorter wavelength). The use of shorter
wavelength ensures fine spatial resolution of these parameters to depict oceanographic
and atmospheric characteristics of any region having significant spaio-temporal
variability.
Off the southwest coast of India is such an area showing very significant
spatio-temporal oceanographic and atmospheric variability due to the seasonally
reversing surface winds and currents. Consequently, the region is enriched with
features like upwelling, sinking, eddies, fronts, etc. Among them, upwelling brings
nutrient-rich waters from subsurface layers to surface layers. During this process
primary production enhances, which is measured in ocean colour sensors as high
values of Chl a. Vertical attenuation depth of incident solar radiation (Kd) and Aerosol
Optical Depth (AOD) are another two parameters provided by ocean colour sensors.
Kd is also susceptible to undergo significant seasonal variability due to the changes in
the content of Chl a in the water column. Moreover, Kd is affected by sediment
transport in the upper layers as the region experiences land drainage resulting from
copious rainfall. The wide range of variability of wind speed and direction may also
influence the aerosol source / transport and consequently AOD.
The present doctoral thesis concentrates on the utility of Chl a, Kd and AODprovided by satellite ocean colour sensors to understand oceanographic and
atmospheric variability off the southwest coast of India. The thesis is divided into six
Chapters with further subdivisions
Description:
faculty
of Marine Sciences,Cochin University of Science and Technology
Bright Singh, I S; Seena, Jose; Rosamma, Philip; Mohandas, A; Jayesh, P(Elsevier, December 26, 2010)
[+]
[-]
Abstract:
Lack of shrimp cell lines has hindered the study of pollutants which adversely affects shrimp health and
its export value. In this context a primary haemocyte culture developed from Penaeus monodon was
employed for assessing the cytotoxicity and genotoxicity of two heavy metal compounds, cadmium
chloride and mercuric chloride and two organophosphate insecticides, malathion and monocrotophos.
Using MTT assay 12 h IC50 values calculated were 31.09 16.27 mM and 5.52 1.16 mM for cadmium
chloride and mercuric chloride and 59.94 52.30 mg l 1 and 186.76 77.00 mg l 1 for malathion and
monocrotophos respectively. Employing Comet assay, DNA damage inflicted by these pollutants on
haemocytes were evaluated and the pollutants induced DNA damage in >60% of the cells. The study
suggested that haemocyte culture could be used as a tool for quantifying cytotoxicity and genotoxicity of
aquaculture drugs, management chemicals and pollutants