Aniladevi Kunjamma, K P; Dr. Babu, Philip(Cochin University of Science and Technology, April , 2008)
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Abstract:
Man uses a variety of synthetic material for his comfortable materialistic
life. Thus human interactions may become harmful for various terrestrial and aquatic
lives. This is by contaminating their habitat and by becoming a threat to organisms
itself. Thus the application and dispersal of several organic pollutants can lead to the
development of several mutated forms of the species when exposed to sublethal
concentrations of the pollutants. Otherwise, a decrease in number or extinction of
these exposed species from earth's face may happen. Pesticides, we use for the
benefit of crop yield, but its persistence may become havoc to non-target organism.
Pesticides reaching a reservoir can subsequently enter the higher trophic levels.
Organophosphorus compounds have replaced all other pesticides, due to its acute
toxicity and non-persistent nature.Hence the present study has concentrated on the toxicity of the largest
market-selling and multipurpose pesticide, chlorpyrifos on the commonly edible
aquatic organism, fish. The euryhaline cichlid Oreochromis mossambicus was
selected as animal model. The study has concentrated on investigating biochemical
parameters like tissue-specific enzymes, antioxidant and lipid-peroxidation
parameters, haematological and histological observations and pesticide residue
analysis.Major findings of this work have indicated the possibility of aquatic toxicity
to the fish on exposure to the insecticide chlorpyrifos. The insecticide was found as
effective to induce structural alteration, depletion in protein content, decrease in
different metabolic enzyme levels and to progress lipid peroxidation on a prolonged
exposure of 21 days. The ion-transport mechanism was found to be adversely
affected. Electrophoretic analysis revealed the disappearance of several protein bands
after 21days of exposure to chlorpyrifos. Residue, analysis by gas chromatography
explored the levels of chlorpyrifos retaining on the edible tissue portions during
exposure period of 21days and also on a recovery period of 10 days.
Description:
Department of Marine Biology, Microbiology and Biochemistry, Cochin
University of Science and Technology.
Priya,M; Babu,Philip(DEPARTMENT OF MARINE BIOLOGY, MICROBIOLOGY AND BIOCHEMISTRY, 2001)
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Abstract:
In this project, an attempt has been made to study the stability of
erythrocyte and lysosomal membranes biochemically. Erythrocytes were chosen for the study because of their ready availability and relative simplicity. Biological membranes forming closed boundaries between compartments of varying composition consist mainly of proteins and lipids. They are asymmetric, fluid structures that are thermodynamically stable and metabolically active. Normal cellular function begins with normal membrane
structure and any variation in it may upset the normal functions. The degree of fluidity of a membrane depends on the chain length of its lipids and degree of unsaturation
of constituent fatty acids. In response to environmental changes, many cells can regulate
composition of their membranes to maintain the overall semi fluid environment
necessary for many membrane associated functions. The assembly and
Maintenance of membrane structures in cells is a dynamic process. The
components are not only synthesized and inserted into a growing membrane but
are also continuously degraded at a slower rate. This turnover process varies
with each individual molecule.Lysosomes are important in the catabolic processes occurring in the cell. Lysosomes contain hydrolytic enzymes and are stable
under normal conditions. In certain pathological conditions, the lysosomal
membrane may rupture, releasing the hydrolytic enzymes into the cell and
digestion of cell takes place as a whole. This is very dangerous. In normal
life processes of multi cellular organisms, lysosomes rupture following the
death of a cell and it may have some value as a built in mechanism for selfremoval
of dead cells.An attempt has also been made in this project towards developing
lysosome membrane stability as an index of fish spoilage during storage.
Different membranes within the cell and between cells have different
compositions as reflected in the ratio of protein to lipid. The difference is
not surprising given the very different functions of membranes