Nanoemulsion of cashew gum and clove essential oil (Ocimum gratissimum Linn) potentiating antioxidant and antimicrobial activity

Int J Biol Macromol. 2021 Dec 15;193(Pt A):100-108. doi: 10.1016/j.ijbiomac.2021.09.195. Epub 2021 Oct 7.

Abstract

In this study, nanoemulsions of essential oil from Ocimumgratissimum (Linn) (EO) were produced using low and high energy techniques using cashew gum (CG) as a co-surfactant. The main constituents of the EO were determined by Gas Chromatography coupled with Mass Spectrometry (GC-MS), and their presence in the EO and in the formulations verified by Fourier Transform Infrared Spectroscopy (FTIR) and UV-visible spectrophotometry was observed the encapsulation efficiency (EE%), with colloidal stability. Nuclear magnetic resonance (NMR) was used to study cashew gum. Dynamic light scattering analysis (DLS) determined the nanoemulsion Z means, polydispersity index and the Zeta potential value, nanoparticle tracking analysis (NTA) were determined. The nanostructured EO showed better antibacterial action against the pathogenic gastroenteritis species Staphylococcus aureus, Escherichia coli and Salmonella enterica when compared to free EO. Atomic Force Microscopy (AFM) was used for morphological analysis of the nanoparticle and study of the action of the nanoemulsion through images of the cellular morphology of S. enterica. The antioxidant activity was evaluated against the ABTS radical (2,2'-azino-bis diazonium salt (3-ethylbenzothiazoline-6-sulfonic acid)). The encapsulation of EO in a nanostructured system improved its antibacterial and antioxidant activity, the low energy synthesis showed greater storage stability, remaining stable for 37 days.

Keywords: Conservation; Gastroenteritis; Nanotechnology.

MeSH terms

  • Anti-Bacterial Agents / chemistry*
  • Emulsions / chemistry*
  • Ocimum / metabolism*
  • Oils, Volatile / chemistry*
  • Plant Gums / chemistry*
  • Plant Leaves / metabolism

Substances

  • Anti-Bacterial Agents
  • Emulsions
  • Oils, Volatile
  • Plant Gums