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Soybean, one of the most abundant plants, has been cultivated around the world as a familiar crop. Especially, most of the soybean is globally used as a crop to obtain the oil. The degreased soybean contains a lot of protein in it. The part of the degreased soybean is used for the food of human consumption and livestock feed, however most of this are discarded as industrial waste throughout the world. Therefore, we demonstrated the preparation of bioplastics consisting of soy protein. Although the soy protein without the cross-linking reaction by formaldehyde (HCHO) was collapsed in water, bioplastics were stable in water. Additionally, the bending strength of the bioplastic increased with the HCHO concentration and showed the maximum value of approximately 35 MPa at a 1% HCHO concentration. Surprisingly, this bending strength value was the same as that of polyethylene. In contrast, the infrared spectra indicated the formation of methylene cross-linking between the basic amino acids, such as lysine and arginine. Finally, we estimated the biodegradable property of the bioplastic by pronase, one of the proteolytic enzymes. As a result, this bioplastic showed the weight loss of approximately 30% after the incubation time of 6 days. These results suggested that the bioplastic consisting of soy protein possesses a biodegradable property. Therefore, the bioplastic consisting of soybean may have the potential to be used as a biodegradable material, such as agricultural materials, industrial parts, and disposable items. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrated the immobilization of double-stranded DNA onto the glass beads by psoralen, one of the DNA-intercalators in nature. As a result, DNA-immobilized glass beads (DNA-P-beads) were prepared by the intercalation of psoralen, which was immobilized onto the glass surface, onto the double-stranded DNA. These DNA-P-beads formed covalent bondings between psoralen and the nucleic acid base by 365nm UV irradiation. The amount of immobilized-DNA was 0.24mg per gram of glass beads. These DNA-P-beads were stable in water, and the DNA on the bead surface maintained its double-stranded structure. These DNA-P-beads selectively removed the planar-structure containing harmful compounds, such as dioxin and polychlorinated biphenyl (PCB) derivatives, from an aqueous multi-component solution. Additionally, a DNA-P-bead column effectively removed harmful compounds. Furthermore, the DNA-P-bead column could be reused by the addition of common organic solvents, such as ethanol. [Copyright &y& Elsevier]

Abstract: Water-soluble β-cyclodextrin-immobilized poly(ethyleneimine) (PEICD) was synthesized by the grafting of β-cyclodextrin to the branched poly(ethyleneimine). In an aqueous solution, this PEICD polymer could encapsulate bisphenol A, known to be a harmful compound. Additionally, the stability constant of bisphenol A to the PEICD polymer was 1.1×104 M−1. However, the water-solubility of PEICD has been making it difficult to utilize it as an environmental material. Therefore, we prepared the DNA–PEICD composite material by mixing the double-stranded DNA and PEICD. This DNA–PEICD composite material was extremely stable in water and possessed both properties of the intercalation into the double-stranded DNA and the encapsulation into the CD cavity. As a result, this material can accumulate various harmful compounds, such as dioxin- and polychlorobiphenyl (PCB)-derivatives and bisphenol A, from a multi-component solution. Therefore, the DNA–PEICD composite material may have the potential to be used as an environmental material. [Copyright &y& Elsevier]

Abstract: Large amounts of DNA-enriched biomaterials, such as salmon milts and shellfish gonads, are discarded as industrial waste around the world. Therefore, the utilizations of DNA with the specific function are important for the biomaterial science and the curce technology. We could convert the discarded DNA to an enzymatic collapsible material by the addition of DNA to the artificial polymer material, such as nylon. Although these DNA–artificial polymer composite materials were stable in water, these materials indicated the collapsibility at the DNA-hydrolyzed enzyme, such as Micrococcal nuclease, condition. Additionally, these collapsibilities under enzyme condition were controlled by the number of imino groups in the components of the artificial polymer. Furthermore, these composite materials could create the fiber form with a highly ordered molecular orientation by the reaction at the liquid/liquid interface. The DNA–artificial polymer composite materials may have the potential utility as a novel bio-, medical-, and environmental materials with the enzymatic collapsibility and degradability. [Copyright &y& Elsevier]

In the present study, a dialytic method that uses a DNA aqueous solution to remove and enrich dioxins from polluted water was proposed. Circular dichroism (CD) and fluorescent spectra indicated that dibenzo-p-dioxin (DD), dibenzofuran (DF) and biphenyl (BP), which are dioxin derivatives, form complexes with DNA. Their experimental dialytic sorption coefficients were measured by quantifying the concentrations of DD, DF, and BP in aqueous solutions before and after dialysis of the DNA solution, and the values were 2.1×105, 1.3×105, and 1.5×107, respectively. As a simulated water treatment model, DNA solution was dialyzed in an aqueous mixture of DD, DF, and BP for 96 h, the HPLC studies showed that the dioxin derivatives have been concentrated in the DNA solution about 200 times. The dialyzed DNA solution was reusable by an extraction with hexane. [Copyright &y& Elsevier]