biomarkers are assigned as early warning systems regarding aquatic organisms exposed to pollutants. among which, however, measurement of esterase enzymes activity specially cholinesterase of fish tissues, is a marker for exposure to organophosphate pesticide and carbamates, and this biomarker has been used widely in broad range of investigations. a number of capoeta capoeta gracilis (:cyprinida...

the main objective of this study was to purify and characterize an esterase from shewanella sp f88. the enzyme was purified 41-fold and an overall yield of 21 %, using a two-step procedure, including ammonium sulfate precipitation and q-sepharore chromatography. molecular weight of the enzyme was 62.3 kda according to sds-page data. the enzyme showed an optimum activity at ph 6.5 and 58 ˚c. evo...

the toxicity of chlorpyrifos to three iranian populations of two-spotted spider mite, collected from isfahan (isr), yazd (yz) and guilan (gus2) provinces were surveyed using the residual contact vial bioassay. the bioassay results showed that resistance ratios of isr and yz populations were 176.90 and 9.78 fold compared to the gus2 population, respectively. determination of esterase and glutath...

Specific esterase activity, a property generally ascribed to cells of granulocytic origin, was found in abnormal erythroid precursors obtained from the bone marrows of six patients with untreated erythroleukemia. These erythroblasts also showed nonspecific esterase activity. Neither specific nor nonspecific esterase activity was detected in erythroid precursors obtained from the bone marrows of...

Naphthyl esterase and platelet-activating factor (PAF)-acetylhydrolase activities were detected in the salivary glands of the cat flea, Ctenocephalides felis. Salivary naphthyl esterase activity is disgorged during exploratory probing. Whole extracts of salivary glands contain esterase activity against the short-chain naphthyl esters alpha-naphthyl acetate (approximately 210pmol/min/gland pair;...

fumigant toxicity of rosemary essential oil on abamectin-resistant vs. susceptible populations of two spotted spider mites, tetranychus urticae koch was studied under laboratory conditions. results indicated that fumigant toxicity of rosemary essential oil on the susceptible population was 3.06 times higher than that of the resistant one. accordingly, there was a slight cross resistance observe...