Gamma oryzanol (GO), a bioactive ingredient found in rice bran oil, performs a variety of biological effects such as antioxidant activity, reduction of total cholesterol, anti‐inflammation, and antidiabetes. However, GO is water‐insoluble and normally degrades through oxidation. Thus a nano‐encapsulation technique was investigated to improve its stability and quality. In this research, gamma oryzanol was successfully encapsulated into zein nanoparticles. The fabrication parameters including pH, zein concentration (0.3, 0.4, and 0.5% w/v), and % GO loading (30, 40, and 50% by weight) were investigated. Particle size, zeta potential, yield, encapsulation efficiency and the stability or GO retention during the storage were determined. The morphology of gamma oryzanol loaded zein nanoparticles (GOZNs) was observed by scanning electron micrographs and transmission electron microscope. The increase of zein concentration and % GO loading resulted to an increase of yield, encapsulation efficiency, and particle size. The particle size of the GOZNs ranged from 93.24–350.93, and 144.13–833.27, and 145.27–993.13 nm for each zein concentration with 3 loading levels, respectively. Nano‐encapsulation exhibited higher % GO retention compared with nonencapsulated GO during 60 days storage both at 4°C and −18°C. In vitro study indicated the sustained release of GO in the simulated gastric fluid followed by simulated intestinal fluid. This finding indicated a high potential for the application of insoluble GO with improved stability by encapsulation with the hydrophobic zein protein.

Fragrances, a mixture of various aromatic compounds, usually have low aqueous solubility and instability to the environment. This research aimed to fabricate the encapsulation of two fragrances in zein nanoparticles and apply it in fabric softener to sustain the fabric with long‐lasting fragrance. Pink fruity fragrances (PF) and white floral fragrances (WF) encapsulated zein nanoparticles (PF‐ZNs and WF‐ZNs) were prepared by the liquid–liquid dispersion method. Zein and fragrances were mixed and immediately poured under high‐speed homogenizer into citrate buffer containing Tween 20 as a surfactant, and ethanol was removed using a rotary vacuum evaporator. PF‐ZNs and WF‐ZNs obtained exhibited spherical shape with average sizes at 219.1 ± 7.7 and 301.1 ± 9.8 nm, respectively. The encapsulation efficiency of PF‐ZNs, at 69.15 ± 1.31 %, was significantly higher than that of the WF‐ZNs, at 63.91 ± 1.40% (P < .05). Thermal gravimetric analysis (TGA) indicated that both fragrances' thermal stability was improved after the encapsulation. The PF‐ZNs and WF‐ZNs were added to fabric softeners and applied to three types of fabrics: cotton, polyester (TK), and blends of cotton/polyester (TC), and the fragrance remaining in the fabrics for 30 days of storage were determined by gas chromatography. The retention of both PF and WF was improved in all fabrics, and significant effects were performed in the cotton fabric with PF‐ZNs. The results showed the potential to use the fragrances encapsulated in zein nanoparticles as fabric softener to improve fabrics' long‐lasting properties, especially for cotton.

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The distribution and adhesion of microcapsules on fabric surfaces are crucial factors for the production of long-lasting fragrance textiles. The objective of this research was to study the adhesion property of a softener containing microencapsulated fragrances on fabrics. Pink fruity fragrance (PF), and white floral fragrance (WF) were encapsulated with poly (methyl methacrylate) or PMMA, using the micro-suspension photopolymerization method, to form PF-PMMA, and WF-PMMA microcapsules, respectively. The particle sizes and zeta potential of the capsules were determined. The PF-PMMA and WF-PMMA were added to the fabric softener before being applied to three types of fabrics, cotton, TK (polyester), and TC (a mixture of cotton and TK). Surface morphologies of the fabrics treated with the softener were studied by scanning electron microscope (SEM). Interactions between the microcapsules and the fabrics were studied using a contract angle measurement device, Fourier Transform Infrared (FTIR) spectrometer, and Raman microscope. The average size of PF-PMMA was 484.8 ± 4.0 nm, smaller than that of WF-PMMA (664.6 ± 2.9 nm). Cotton was found to be hydrophilic with a rough surface due to cellulose fibers, while TK surface was smooth and hydrophobic. The different fiber structures and surface properties of the fabrics gave rise to different adhesion behavior, evidenced by the contract angle and Raman microscopic data. After 60 days of storage, the microencapsulated fragrances were found to remain on the cotton surfaces, but that on the TC and the TK surfaces disappeared. The results illustrated the interaction between the fabric surface and the microcapsules encapsulated with fragrances, which affected their adhesion. The knowledge obtained can be applied to the development of household products with long-lasting fragrances.