Characterisation and inhibition studies of Helicoverpa armigera (Hübner) gut α‐amylase. Issue 9 (20th October 2014)

• Record Type: Journal Article
• Authors: Kaur, Rimaljeet; Gupta, Anil K; Taggar, Gaurav K
• Is Part Of: Pest management science. Volume 71:Issue 9(2015:Sep.)
• Page Start: 1228
• Page End: 1237
• Publication Date: 2014-10-20
• Subjects: Pests -- Control -- Periodicals; Pesticides -- Periodicals; 632.9
• DOI: 10.1002/ps.3911
• Languages: English
• ISSNs: 1526-498X

Abstract

<abstract abstract-type="main" id="ps3911-abs-0001"> <title>Abstract</title> <sec id="ps3911-sec-0001" sec-type="section"> <title>BACKGROUND</title> <p id="ps3911-para-0001">The survival of a devastating pest, <italic>Helicoverpa armigera</italic>, is mainly dependent on the availability of α‐amylase. Therefore, characterising <italic>H. armigera α</italic>‐amylase and targeting it with effective inhibitors could aid in reducing its damaging effects.</p> </sec> <sec id="ps3911-sec-0002" sec-type="section"> <title>RESULTS</title> <p id="ps3911-para-0002"> <italic>H. armigera</italic> gut possessed four isozymes of α‐amylase. The molecular weight of the major purified isozyme ranged from 79 to 81 kDa. The purified enzyme was identified to be <italic>α</italic>‐amylase on the basis of products formed from starch. The optimum pH and temperature were 10.0 and 50 °C respectively. The activation energy was 5.7 kcal mol<sup>−1</sup>. The enzyme showed high activity with starch and amylopectin, whereas dextrins were poor substrates. The Michaelis constant <italic>K</italic><sub>m</sub> with starch, amylose and amylopectin was 0.45, 1.23 and 0.11 mg mL<sup>−1</sup> respectively. ZnSO<sub>4</sub>, FeSO<sub>4</sub>, CuSO<sub>4</sub>, citric acid, oxalic acid and salicylic acid were potent inhibitors. ZnSO<sub>4</sub>, salicylic acid and pigeonpea <italic>α</italic>‐amylase inhibitor (∼21.0 kDa) acted primarily as competitive inhibitors, FeSO<sub>4</sub> and citric acid displayed mainly anticompetitive behaviour, while CuSO<sub>4</sub> and oxalic acid behaved mainly as non‐competitive inhibitors.</p> </sec> <sec id="ps3911-sec-0003" sec-type="section"> <title>CONCLUSIONS</title> <p id="ps3911-para-0003">The identification of effective ecofriendly inhibitors could help in managing <italic>H. armigera</italic> infestation. © 2014 Society of Chemical Industry</p> </sec> </abstract>