Enhancing Nematicidal Effect of Prodigiosin via Nano-Encapsulation Using Chitosan as a Novel Carrier Substance

Abstract

Abstract In this study, Chitosan (CS) was newly found as an effective carrier for nano-encapsulation of Pg by spray drying technique for enhancing its bioactivity. Among various tested polymers, CS was screened as the most suitable substance for creating encapsulated Pg/CS nanoparticles (E-Pg/CS-NPs) with high recovery yield and good nanoscale properties. CS was further combined with other carbohydrate polymers and used for nano-encapsulation of Pg, however, no enhancing yield or better properties of encapsulated Pg NPs were found. Further experiments indicated that the size of the spaying needle of 55µm and the Pg concentration used at 0.05% were the most effective for producing E-Pg/CS-NPs. In nanoscale properties characterization, the E-Pg/CS-NPs were found spherical with smooth surfaces, good stability (Zeta potential of + 80.1mV), and average sizes at 529.5nm. Especially, the E-Pg/CS-NPs demonstrated a potent nematicidal effect against both J2-nematodes and their egg-hatching, besides, the activity of E-Pg/CS-NPs was improved by about 4-fold compared with pure Pg. The molecular docking and enzyme inhibition assays suggested the possible path-way of the nematicidal effect of Pg released from E-Pg/CS-NPs via inhibition of acetylcholinesterase. This study thus provides a novel and effective protocol to produce E-Pg/CS-NPs with potential use for managing black pepper nematodes.