Lignin nanoparticles from Ayurvedic industry spent materials: Applications in Pickering emulsions for curcumin and vitamin D3 encapsulation.

ABSTRACT

Lignin nanoparticles (LNP), extracted from spent materials of Dashamoola Arishta (Ayurvedic formulation), shared a molecular weight of 14.42 kDa with commercial lignin. Processed into LNPs (496.43 ± 0.54 nm) via planetary ball milling, they demonstrated stability at pH 8.0 with a zeta potential of -32 ± 0.27 mV. Operating as Pickering particles, LNP encapsulated curcumin and vitamin D3 in sunflower oil, forming LnE + Cu + vD3 nanoemulsions (particle size 347.40 ± 0.71 nm, zeta potential -42.27 ± 0.72 mV) with high encapsulation efficiencies (curcumin 87.95 ± 0.21%, vitamin D3 72.66 ± 0.11%). The LnE + Cu + vD3 emulsion exhibited stability without phase separation over 90 days at room (27 ± 2 °C) and refrigeration (4 ± 1 °C) temperatures. Remarkably, LnE + Cu + vD3 exhibited reduced toxicity, causing 29.32% and 34.99% cell death in L6 and RAW264.7 cells respectively, at the highest concentration (50 µg/mL). This underscores the potential valorization of Ayurvedic industry spent materials for diverse industrial applications.