Nanostructured lipid carriers loaded with hyssop essential oil: Antioxidant and antimicrobial platform for food preservation

• NLCs (nanostructure lipid carriers) were loaded with Hyssop essential oil (HEO). • The main compounds of HEO were pinocamphone 40.72 % and β-pinene 13.54 %. • The HEO-loaded NLCs were physically stable over 30-day at 4 °C. • The HEO-loaded NLCs had better antioxidant stability than HEO over 30-day at 4 °C. • The HEO-loaded NLCs showed more antimicrobial action than HEO against some studied microbes. Hyssop essential oil (HEO) possesses strong antioxidant and antimicrobial properties. The gas chromatography-mass spectroscopy (GC–MS) profile indicates that HEO consists of pinocamphone (40.72 %) and β-pinene (13.54 %). However, the practical use is limited by high volatility, poor water solubility, and physicochemical instability. In this study, nanostructured lipid carriers (NLCs) were developed to encapsulate HEO using high-shear homogenization to improve the water dispersibility, antioxidant stability, and antimicrobial function of HEO. The resulting HEO-loaded NLCs exhibited favorable physicochemical characteristics, including nanoscale size, uniform polydispersity, high loading capacity of >20 %, and encapsulation efficiency of >85 %. Structural analyses by X-ray diffraction and FTIR confirmed successful physical encapsulation of HEO into the lipid matrix. Antioxidant assays showed that NLC 1 maintained superior antioxidant activity compared to free HEO after 30 days of storage at 4 °C. Based on the minimal bactericidal concentration (MBC) of HEO, a more concentrated formulation (NLC 2 ) was developed, which demonstrated enhanced antimicrobial efficacy—up to fourfold higher than free HEO against Bacillus subtilis , and twofold higher against Pseudomonas aeruginosa and Candida albicans . Both formulations exhibited good colloidal and physicochemical stability during storage. These findings suggest that HEO-loaded NLCs represent a promising delivery system for natural preservatives in food systems, with potential to enhance shelf life, reduce reliance on synthetic additives, and improve the microbiological safety and oxidative stability of processed foods.