Locusts Extraction And Enzymatic Properties Of Digestive Enzymes And Drury Enzyme Inhibitors Research

Insects and animals are different digestive enzymes to digest food adaptability within theenvironmental conditions, including differences in the reaction temperature, pH, ionic strength,range of conditions, and the difference is the structure itself, enzymes, enzyme activity leads toadaptive range varies in width. According to the object can be divided into digestive protease,amylase, cellulase. A wide variety of insects, environmental adaptability, huge number of widelyrecipes, digestive enzymes and their activity is high, with research value and potentialapplications. Meanwhile, research in favor of its activity characteristics applied to otherindustries, while suppressing research through the use of insect activity, reduce insect damage.In this study,0.9%NaCl saline as the extraction solvent to locusts as test material, thecontents of the digestive tract for the locusts were separated by centrifugation and discard thepellet. Different saturation with ammonium sulfate precipitation, ammonium sulfate saturationto determine the best of each enzyme. Best ammonium sulfate saturation of70%proteaseenzyme activity was10.86U. Best of ammonium sulfate to60%saturation of cellulase enzymeactivity was1.63U. Best ammonium sulfate saturation of40%amylase enzyme activity is42.86U.The dialyzed enzyme solution locust gut infrared scanning patterns, detect chemicalfunctional groups composed of the digestive tract, can be drawn from the pattern analysis locustgut rich in amino acids, carboxylic acids, amides substances, indicating that a protein extract orenzymes.Influence of temperature on the enzyme activity and thermal stability:The optimumtemperature of locusts protease is55℃; optimum temperature of locusts amylase is35℃;optimum temperature of cellulase locusts40℃. Locust protease stability at30℃; cellulases aremore stable at20-60℃; amylase stable within20-50℃.PH effects on enzyme activity and pH stability: The optimum pH of9Locust protease;optimal pH is6amylase, cellulase optimum pH of5. Under alkaline protease stabilityconditions better in acidic environments, the enzyme activity decreased rapidly; amylase,cellulase and stability in acidic when better, under alkaline conditions enzyme activity decreasedrapidly. At pH7, the three kinds of digestive enzymes stability are very good.Effect of metal ions on the enzyme activity: Cu2+to promote the role of proteases, Fe2+,Pb2+, Zn2+and EDTA on protease inhibition performance, the other four metal ions on protease no obvious promotion or inhibition. Fe2+and Mg2+to promote the role of cellulases, inhibitionof cellulase produced is Cu2+, Pb2+and Zn2+, the other four non-obvious promotion or inhibition.Cu2+, Ca2+and K+to promote the role of amylase, Fe2+, Mg2+, Zn2+and EDTA on amylaseactivity was inhibited, Pb2+and K+had little effect on amylase activity.Emamectin and cypermethrin on the inhibition of protease activity: Cypermethrin andemamectin have some protease inhibition, emamectin protease inhibition better, cypermethrincompared with emamectin badly.Application of enzyme inhibition: Drury insects as an object, analyzes eight kinds of lethaleffects of pesticides on third instar larvae of the fall webworm,15%chlorpyrifos EC Avi lethaleffect of the fastest white moth in36h100%died. Cypermethrin, chlorpyrifos48h deaths havereached100%,40%methidathion EC to reach100%in72h death.25%deltamethrin EC,63.1%kill single·thuringiensis WP1.8%abamectin EC,1%emamectin benzoate effervescent fourpesticides on the fall webworm the death rate is relatively slow. Which deltamethrin, abamectinEC and the role of emamectin benzoate is a contact and stomach poison, killingone· thuringiensis role is to absorb contact and the effect of these four pesticides slow the larvaemay be due to inhalation of pesticides, metabolic disorders caused by an enzyme, through theprocess of progressive metabolic toxicity, leading to death, the effect of four pesticides slower.