A comprehensive analysis integrating phenotypic assessment uncovering thornless cultivar lineages in Aralia elata.

Aralia elata is an Araliaceae woody plant species found in Northeastern Asia. To understand how genetic pools are distributed for A.elata clones, we were to analyze the population structure of A.elata cultivars and identify how these are correlated with thorn-related phenotype which determines the utility of A.elata. We found that the de novo assembled genome of 'Yeongchun' shared major genomic compartments with the public A.elata genome assembled from the wild-type from China. To identify the population structure of the 32 Korean and Japanese cultivars, we identified 44 SSR markers and revealed three main sub-clusters using ΔK analysis with one isolated cultivar. Machine-learning based clustering with thorn-related phenotype correlated moderately with population structure based on SSR analysis suggested multi-layered genetic regulation of thorn-related phenotypes. Thus, we revealed genetic lineage of A.elata and uncovered isolated cultivar which can provide new genetic material for further breeding.

Phosphorylcholine-based encoded hydrogel microparticles with enhanced fouling resistance for multiplex immunoassays.

Due to the growing interest in multiplex protein detection, encoded hydrogel microparticles have received attention as a possible path to high performance multiplex immunoassays through a combination of high multiplexing capability and enhanced binding kinetics. However, their practical operation in real complex samples is still limited because polyethylene glycol, which is the main component of hydrogel particles, suffers from oxidative damage and relatively high fouling properties in biochemical solutions. Here, we introduce poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-based encoded hydrogel microparticles to perform fouling-resistant multiplex immunoassays, where the anti-fouling characteristics are attributed to the zwitterionic PMPC. By applying a newly developed molding lithography technique, viscous PMPCs with low reactivity were successfully incorporated into the hydrogel network while maintaining uniformity and rigidity for use in multiplex immunoassays. Non-specific protein adsorption on the PMPC particles was reduced by about 37.5% compared to that of conventional PEG particles, which leads to better assay sensitivity. We also validate the multiplex capability of the PMPC particles by performing multiplex detection of two target proteins. Furthermore, we verify that the PMPC particles have a 70% enhancement in anti-fouling characteristics compared to PEG particles in human platelet-rich plasma, potentiating a practical immunoassay platform for clinical diagnosis.

Optimization of Anisotropic Crystalline Structure of Molecular Necklace-like Polyrotaxane for Tough Piezoelectric Elastomer.

While piezoelectric materials are applied in various fields, they generally exhibit poor mechanical toughness. To increase the applicability of these, their mechanical properties need to be improved. In this study, a tough piezoelectric polyrotaxane (PRX) elastomer was developed by blending PRX samples of two different lengths, formed using 10K and 35K poly(ethylene glycol), to align dipole moments for optimization of the piezoelectricity characteristics. The effects of the blending ratio on the crystalline structure of the obtained PRX elastomer were investigated by X-ray diffraction analysis and transmission electron microscopy. In addition, the ferroelectric and piezoelectric properties of the PRX elastomer were evaluated based on its polarization hysteresis loop and voltage generation characteristics, respectively. The PRX elastomer formed by using a ratio of 3:1 (ePR10k7535k25) exhibited a long-range-ordered anisotropic crystalline structure, resulting in a large polarization (Pr) value. As a result, ePR10k7535k25 showed greatly enhanced piezosensitivity against the mechanical vibrations generated by respiratory signals.

Scratch Properties of Clear Coat for Automotive Coating Comprising Molecular Necklace Crosslinkers with Silane Functional Groups for Various Environmental Factors.

Automotive coatings, which comprise multiple layers, i.e., primer, base coating, and clear coat layers, are exposed to various environmental conditions that pose various types of damages to them. In particular, the outer layer of the automotive coating, i.e., the clear coat, is affected significantly by such damages. Therefore, a reliable and durable clear coat must be developed to improve the appearance of automobiles. In this study, a new clear coat based on an acrylic-based clear coat modified using polyrotaxane crosslinkers, which are necklace-shaped supramolecules composed of ring-shaped host molecules, is developed and characterized. The effects of polyrotaxane and silane on the scratch properties and mechanisms of the clear coating are analyzed. It is observed that the critical loads of the clear coat from scratch tests can be improved by adding optimal molecular necklace crosslinkers comprising silane functional groups. The improvement in the scratch properties of the modified acrylic-based clear coat may be attributed to the crosslinking characteristics and dynamic molecular movements of the polyrotaxane. In addition, the effects of environmental factors on the scratch characteristics of the modified acrylic-based clear coat are investigated by addressing the scratch durability of the clear coat.

Enhanced Mechanical Strength, Flexibility, and Shape-Restoring Rate of a Drug-Eluting Shape-Memory Polymer by Incorporation of Supramolecular Cross-Linkers.

The purpose of this study is to develop mechanically robust soybean oil and polycaprolactone (PC)-based drug-eluting shape memory polymers (SMPs) containing polyrotaxane (PRX) cross-linkers. Essentially, the dynamic PRX cross-linker-containing methacrylate group is introduced to increase the cross-linking density and flexibility of the SMP to overcome its mechanical limitations. It was confirmed that the elongation and cross-linking density of the PRX-incorporated SMP were increased by 2-4 times compared to neat SMP. In addition, those high mechanical properties of the PRX-incorporated SMP could be maintained after the degradation of the PC by the drug-eluting process.

Identification of an entomopathogenic bacterium, Serratia sp. ANU101, and its hemolytic activity.

Four different bacterial colonies were isolated from an old stock of an entomopathogenic nematode, Steinernema monticolum. They all showed entomopathogenicity to final instar larvae of beet armyworm, Spodoptera exigua, by hemocoelic injection. However, they varied in colony form, susceptibility to antibiotics, and postmortem change of the infected host insects. Biolog microbial identification and 16S rDNA sequence analyses indicate that these are four different species classified into different bacterial genera. owing to high entomopathogenicity and a cadaver color of infected insect host, Serratia sp. was selected as a main symbiotic bacterial species and analyzed for its pathogenicity. Although no virulence of Serratia sp. was detected at oral administration, the bacteria gave significant synergistic pathogenicity to fifth instar S. exigua when it was treated along with a spore-forming entomopathogenic bacterium, Bacillus thuringiensis. The synergistic effect was explained by an immunosuppressive effect of Serratia sp. by its high cytotoxic effect on hemocytes of S. exigua, because Serratia sp. caused septicemia of S. exigua when the bacterial cells were injected into S. exigua hemocoel. The cytotoxic factor(s) was present in the culture medium because the sterilized culture broth possessed high potency in the cytotoxicity, which was specific to granular cells and plasmatocytes, two main immune-associated hemocytes in insects.

Foldable and Extremely Scratch-Resistant Hard Coating Materials from Molecular Necklace-like Cross-Linkers.

A flexible hard coating material displaying extreme scratch resistance and foldable flexibility was developed via the design of an organic-inorganic hybrid coating material employing an alkoxysilyl-functionalized polyrotaxane cross-linker (PRX_Si1). PRX_Si1 has a molecular necklace-like structure that can form organic-inorganic cross-linking points and provide large molecular movements. It was postulated that the scratch resistance and flexibility could be simultaneously increased because of the hybrid cross-linking points and dynamic molecular movements. To confirm this hypothesis, the crystalline structure and mechanical properties of the PRX_Si1-based hard coating material were analyzed via transmission electron microscopy, small-angle X-ray diffraction, tensile, pencil hardness, and scratch tests. Finally, the PRX_Si1-based hard coating material could form homogeneously dispersed nanoscale siloxane crystalline domains, and the strain at the break point was 3 times higher than that of a commercial hard coating material, resulting in no defect formation even after 5000 folding test runs. Moreover, the material displayed extremely high pencil hardness (9H) and scratch resistance.

Identification of two entomopathogenic bacteria from a nematode pathogenic to the Oriental beetle, Blitopertha orientalis.

A pathogenic nematode, Butlerius sp., was isolated from Oriental beetle, Blitopertha orientalis. The infective juveniles exhibited dose- as well as time-dependent entomopathogenicity on the larvae of B. orientalis. Two bacterial species, Providencia vermicola (KACC 91278) and Flavobacterium sp. (KACC 91279), were isolated from the infective juveniles and identified. P. vermicola outnumbered Flavobacterium sp. in the nematode host, in which the colony density of P. vermicola was found to be 21 times higher than that of Flavobacterium sp. However, when the two bacterial species were cocultured in culture media without the nematode host, they showed similar growth rates. Both bacteria induced significant entomopathogenicity against Spodoptera exigua larvae infesting economically important vegetable crops, where P. vermicola was more potent than Flavobacterium sp.

Fabrication of an Anti-Biofouling Plasma-Filtration Membrane by an Electrospinning Process Using Photo-Cross-linkable Zwitterionic Phospholipid Polymers.

The goal of this study is to fabricate a stable plasma filtration membrane with antibiofouling properties via an electrospinning process. To this end, a random-type copolymer consisting of zwitterionic phosphorylcholine (PC) groups and ultraviolet (UV)-cross-linkable phenyl azide groups was synthesized. The zwitterionic PC group provides antibiofouling properties, and the phenyl azide group enables the stable maintenance of the fibrous nanostructure of hydrophilic zwitterion polymers in aqueous medium via a simple UV curing process. To demonstrate the antibiofouling nature of the PC group, a polymer without antibiofouling PC groups was also prepared for comparison. The successful synthesis of the random-type copolymers containing phenyl azide groups was proven by 1H nuclear magnetic resonance and Fourier transform infrared spectroscopy, and the fibrous structure of the prepared membranes was observed by field emission scanning electron microscopy. The antibiofouling properties were analyzed by fluorescein isothiocyanate-labeled bovine serum albumin adsorption and platelet adhesion tests. The experimental results show that membranes containing zwitterionic PC groups exhibited obvious decreases in platelet adhesion and protein adsorption. Platelet-rich plasma solution was filtered using the prepared membranes to test their filtration properties. The sequential filtration process removed 80% and almost 98% of the platelets. This finding confirmed that the membrane retained its blood-inert biomaterial surface in a complex medium that included blood plasma and platelets.