Effects of altering the pullulan/zein ratio on emulsion electrospinning of palm tocotrienol

Tocotrienols possess significant antioxidant properties, but their poor aqueous solubility and oxidation susceptibility limit their bioavailability in oral delivery systems. This study encapsulated palm oil tocotrienol rich fraction (TRF) using emulsion electrospinning using plant-based pullulan (P) and zein (Z) at different ratios (P100:Z0, P75:Z25, P50:Z50, P25:Z75, P0:Z100) to develop fast-disintegrating nanofibers. Formulation capable of forming flexible nanofiber strips were further tested for TRF loading capacities up to 15 %. SEM analysis confirmed the successful nanofibers formation, with fiber diameters in descending order of P75:Z25 > P100:Z0 > P0:Z100 (130.9, 69.6, and 52.3 nm, respectively). Encapsulation efficiency (EE) increased from 71.5 % to 89.0 % across formulations. Increasing TRF loading increased fiber diameter, loading capacity, and EE. P75:Z25 became brittle due to weak polymer interactions, whereas P100:Z0 produced continuous nanofibers with the highest EE (86.5 %), optimal mechanical properties, and fast disintegration (4 s). Despite fast strip disintegration, tocotrienol release from the encapsulated core proceeded gradually over 180 min in vitro, governed by the structured emulsion electrospun matrix. This immediate dispersion coupled with sustained release behaviour demonstrates the system's potential for improving tocotrienol delivery in functional food and nutraceutical applications, particularly for populations with swallowing difficulties.