Shelf-life extension of sweet basil leaves by edible coating with thyme volatile oil encapsulated chitosan nanoparticles.

Abstract Edible coatings have potential to decrease the postharvest losses of several horticultural commodities however; there is no systematic investigation focusing on fresh herbaceous aromatic plants such as basil. Herein, the effects of chitosan (CS), chitosan nanoparticles (CSNPs) and thyme volatile oil (TVO) loaded CSNPs (TVO-CSNPs) as edible coatings on preserving the quality of sweet basil leaves were investigated. All CS coatings considerably extended the shelf life and decreased the weight loss of basil leaves relative to the control. Using TVO-CSNPs showed 2.4-fold higher shelf life than the control. The loss in photosynthetic pigments and volatile oil content were significantly retarded by CS applications more so with TVO-CSNPs treatment. Contrary, treated leaves produced lower malondialdehyde (MDA) and H2O2 and therefore retained the membrane functions compared to the control. All CS applications particularly with TVO-CSNPs considerably motivated the activities of catalase (CAT) and superoxide dismutase (SOD) enzymes and reduced the polyphenol oxidase (PPO) and lipoxyganase (LOX) activities relative to uncoated leaves. Overall, using TVO-CSNPs as an edible coating has a great potential in shelf life extension of basil leaves with satisfactory exterior and interior quality. Thus, it can be a promising approach to preserve the quality of fresh cut aromatic herbs.