RESUMO
Aim: To determine acute toxicity (96 hrs) of malachite green for Lamellidens marginalis and to assess it’s biochemical consequences and antioxidant response against control. Methodology: Fresh water bivalve, Lamellidens marginalis were collected from Rajaram tank, Kolhapur and acclimatized for 7 days. To ascertain the acute effect (96 hrs) of malachite green dye, static bioassay was conducted at 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2 ppm on fresh water bivalve, Lamellidens marginalis. The rate of mortality was recorded and LC0 and LC50 values for 96 hrs were calculated. Estimation of biomolecules like protein, glycogen and lipid and antioxidant activity in different tissues of the organism was estimated. Results: The LC0 and LC50 values were determined by static bioassay method. The effects of LC0 and LC50 concentrations of MG were evaluated by examining the biochemical profile and antioxidant response against control in different tissues like gill, mantle, hepatopancreas and gonad. The maximum significant decrease in glycogen (-29%) (-40.86) and protein (-31.73%) (-43.63%) content was observed in gills at both the concentrations LC0 and LC50 respectively as compared to other tissues. There was highly significant depletion in protein content of all the tissues. Lipid content in all tissues at LC0 concentration showed moderately significant depletion (p <0.01), while at LC50 concentration highly significant depletion (p< 0.001) was recorded. From SOD, CAT and GPx enzymes, SOD enzyme activity increased significantly (p < 0.001) in all tissues at LC50 concentration. Gill and heptopancreas showed significant increase in antioxidant enzymes response at both, LC0 and LC50 groups. Interpretation: Malachite dye induces toxicity, by lowering biochemical content and inducing antioxidant enzyme activity.
RESUMO
The present study was carried out to investigate the effect of colour pigments used for painting the decorative articles like idols, on the freshwater bivalve, Lamellidens marginalis. The effects of sub-chronic exposure were studied by the changes in the biochemical constituents like total protein, glycogen and lactic acid, in different tissues like muscle, mantle, gills, foot, hepatopancreas and gonads for 10 and 20 days period. The glycogen contents in the muscle, mantle and gonads were significantly decreased with increase in concentration of colour pigments. It decreased from 26.77 mg gm-1 in control to 19.17 mg gm-1 at 900 ppm after 20 days of exposure; whereas protein contents in the tissues studied decreased significantly from 22.5 mg gm-1 in control to 15.5 mg gm-1 at 900 ppm after 10 days of exposure. The increase in lactic acid content in all the tissues except gills and gonads may be due to acute hypoxia.
RESUMO
Temperature is a crucial determinant of biogeography, directly affecting the behavioral responses of the organisms. An acute static bioassay was conducted to evaluate the effect of temperature on dimethoate toxicity in a freshwater mussel Lamellidens marginalis. The mussel, were exposed for 96 hr at different concentrations of dimethoate (155.00, 160.00, 165.00, 170.00, 175.00, 180.00, 185.00, 190.00, 195.00, and 200.00 mgl-1) in the month of January when water temperature was 14.9±1.20C and at concentration 35.00, 37.00, 39.00, 41.00, 43.00, 45.00, 47.00, and 49.00 mgl-1 in the month of August when the water temperature was 28.0±0.50C. The LC50 values were calculated from the mortality data obtained (using EPA-Probit analysis version 1.5, statistical software). The 96 hr LC50 value recorded at higher temperature was 36.34mgl-1 and at low temperature was 163.59 mgl-1. The mussel exposed at higher temperature showed more sensitive behavioral responses like huge mucus secretion, sudden closure of shell valves, quick post-mortem changes and increased oxygen consumption in comparison to exposure at low temperature. Therefore, the increasing threat of global warming increases the risk of pesticide toxicity in the exposed organisms.
RESUMO
A comparative study of the collagen of the foot of Lamellidens Sp. and that of the unmodified part of the foot in Mytilus edulis shows marked differences in physical properties, amino acid composition and in the degree of stabilization. But both conform to type I collagen of vertebrates. In these respects, the latter shows agreement with the features characteristic of byssus collagen, which is highly crosslinked, involving dimers and trimers of tyrosine. It is suggested that such differences may reflect the different functions of the organs concerned, the foot of Lamellidens being a locomotary organ of the animal, while the foot of Mytilus edulis is modified for anchorage of the animal. The vertigial part though not morphologically modified shows the essential compositional characteristics of the byssus being a mere remanant of it.