Tobacco mosaic virus (TMV) is a classical viral nanoarchitecture that has been extensively employed as a promising template for the fabrication of novel nanomaterials and nanostructures. Despite being an ideal source, the Escherichia coli -derived TMV nanorod is suffering from tenuous assembly capability and stability. Inspired by the disulfide bond widely employed in biosystems, here we rationally introduce a cysteine into TMV coat protein (TMV-CP) to enable disulfide bond formation between adjacent subunits, thereby radically altering the behaviors of original noncovalent assembling system of wild type TMV-CP. The dramatically enhanced self-assembly capability and stability of the engineered TMV nanorods are observed and the essential roles of disulfide bonds are verified, illustrating a promising strategy to obtain desired genetic-modified nanorods that are inaccessible in plants. We expect this work will benefit the development of TMV-based nanotechnology and encourage the utilization of disulfide bonds in other biomacromolecules for improved properties as nanoscaffolds.

Discrete, three-dimensional (3D) gold nanoparticle (AuNP) tetrahedron nanoarchitectures are successfully self-assembled with DNA origami as template with high purity (>85%). A distinct plasmonic chiral response is experimentally observed from the AuNP tetrahedron nanoarchitectures and appears in a configuration-dependent manner. The chiral optical properties are then rationally engineered by modifying the structural parameters including the AuNP size and interparticle distance. Theoretical study of the AuNP tetrahedron nanoarchitectures shows the dependence of the chiral optical property on the AuNP size and interparticle distance, consistent with the ensemble averaged measurements.

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Proteins were extracted from perilla (Perilla frutescens L. Britton) seed by-products and hydrolyzed with an alkaline protease. Antioxidant peptides were purified from the hydrolysate by size-exclusion chromatography and RP-HPLC. Two peptides with strong antioxidant activity were identified as Tyr-Leu (YL) and Phe-Tyr (FY) with the molecular mass of 294.33 Da and 328.33 Da, respectively. Synthesized YL and FY efficiently quenched free radicals (DPPH, ABTS and hydroxyl radicals) and showed high oxygen radical absorbance capacity. The two peptides also inhibited lipid peroxidation in the rat liver. Furthermore, YL and FY could protect HepG-2 cells against hydrogen peroxide-induced oxidative damage without cytotoxicity. Based on the structure-activity analysis, the Tyr residue was crucial for the antioxidant activity of YL and FY. The results indicate that the protein hydrolysate from perilla seed by-products possessed potent biological activity and can be utilized to develop health-related nutraceutical ingredients.

A high-performance Ni/ZnO–Al2O3–SiO2 adsorbent was developed for reactive adsorption desulfurization (RADS) of diesel. The desulfurization performance of the prepared adsorbents was evaluated in a fixed-bed reactor for treating a hydrotreated diesel with a sulfur content of 1187 ppm. The preparation conditions were investigated, such as aging time, aging temperature, metallic ion concentration, and precipitation temperature. Results showed that the adsorbents performed at a high desulfurization efficiency under the mild preparation conditions. This indicated that smaller crystalline grains were favorable for desulfurization over the Ni/ZnO–Al2O3–SiO2 adsorbent. The adsorbent attained a high adsorption ability of 38.4 mg/g at a breakthrough sulfur level of 20 ppm. The mechanism of deactivation of the adsorbent was also studied and discussed by various characterizations, such as N2 physisorption, powder X-ray diffraction (XRD), ammonia temperature-programmed desorption (NH3–TPD), transmission electron microscopy (TEM), and scanning electron microscopy/energy-dispersive spectrometry (SEM/EDS). The main reasons of the deactivation of the RADS adsorbent include the carbon deposition, the formation of ZnS, and the sintering of the active and support.