Structural characterization of chitosan nanoparticle loaded with Piper nigrum essential oil for biological efficacy against the stored grain pest control.

In this study, Piper nigrum essential oil (PNO) has been encapsulated in chitosan nanoparticle (CS NPs) via ionic gelation method with sodium tripolyphosphate (TPP). The successfully loaded Piper nigrum EO was confirmed by UV-Vis spectrophotometry and X-ray diffraction (XRD) techniques. The average particle size of P. nigrum essential oil loaded chitosan nanoparticle (CS/PNO NPs) showed 527.5 nm with spherical shape morphology. Zeta potential values of the particles were found to be negative -5.34 mV. Encapsulation efficiency and loading efficiency was in the range of 35% to 40% and 4.85% to 7.04% respectively. CS/PNO NPs exhibited strong insecticidal activity against Sitophilus oryzae and Tribolium castaneum. In addition, CS/PNO NPs enhanced the fumigant toxicity and altered the neurotransmitter, acetylcholine in both the stored grain pests. Overall results of nanoformulation indicated that these novel design systems could be promoted in integrated pest management schedule for T. castaneum and S. oryzae.