Chemical composition, pesticidal activities and in-silico investigation of Hedychium spicatum Sm. chloroform extract

Abstract

The present study aimed to identify the bioactive constituents in the chloroform extract of H. spicatum rhizomes (HS-RCLE), further evaluated for its in-vitro pesticidal activities validating via molecular docking techniques. GC/MS analysis of HS-RCLE identified 14 compounds contributing 84.1 % of the total composition. The extract was dominated by oxygenated sesquiterpenes (43.1 %) with curcumenone (25.2 %) and coronarin E (14.8 %) as the major compounds. The extract recorded 89.4 % egg hatchability inhibition and 82.6 % immobility of Meloidogyne incognita, 66.7 % insecticidal activity on Spodoptera litura, 100 % phytotoxic activity on Raphanus raphanistrum seeds, and 74.7 % anti-fungal activity on Curvularia lunata at the respective highest dose studied. The biological activities were furthermore validated by using docking studies on certain proteins/enzymes namely acetylcholinesterase (PBD ID: IC2O), carboxylesterase (PDB ID: 1CI8), acetohydroxyacid synthase (PBD ID: 1YHZ) and trihydroxy naphthalene reductase (PBD ID: 3HNR). The bioactivity of the major constituents of the extract was predicted with the help of in silico PASS studies. HS-RCLE was observed to be a viable alternative source of natural pesticidal agents and paves the way for further studies on its mechanistic approaches and field trials to ascertain its pesticidal studies.

Key words
Curvularia lunata; Hedychium spicatum; in silico; Meloidogyne incognita; Raphanus raphanistrum; Spodoptera litura