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Biology subjects

Odahara, M.

Publications and source records attributed to Odahara, M..

4 recordsLinked to original sources

Thermal Conductivity of Artificial Materials Engineered from Plant and Bacterial Cells

Bio-based materials are known for their excellent biodegradability and, in some cases, their potential to fix carbon dioxide. Owing to these properties, they are increasingly being utilized as environmentally friendly alternatives across various applications. In this study, we focused on using living cells themselves as material components, aiming to evaluate their potential as substitutes for conventional plastic-based thermal insulators. We selected two types of cells, photosynthetic purple non-sulfur bacterium Rhodovulum sulfidophilum and tobacco BY-2 plant suspension cells. After optimizing solidification conditions through the addition of pectin and cellulose nanofibers, we measured the thermal conductivity of the solidified cells under atmospheric pressure. The results showed that R. sulfidophilum exhibited 0.0553 W/m{middle dot}K, while BY-2 exhibited a thermal conductivity of 0.043 W/m{middle dot}K. Both values indicate relatively low thermal conductivity compared to existing bio-based materials, suggesting high insulation performance. Among the solidified cells, the solidified BY-2 cells showed minimal variation in thermal insulation performance under pressure changes, and had a low thermal emissivity as revealed by FT-IR analysis. Based on these findings, we propose that cell-derived materials can serve as potentially biodegradable bio-based thermal insulation materials.

bioengineering↗

Low-salinity medium for large-scale biomass production of the marine purple photosynthetic bacterium Rhodovulum sulfidophilum

Marine purple non-sulfur bacteria such as Rhodovulum sulfidophilum are versatile due to their diverse applications in bioremediation, biotechnological production of useful materials, industrial production of value-added compounds, and agricultural fertilizers. Our previous study demonstrated the potential of its lysed and dried biomass as a nitrogen fertilizer for plant production. However, large-scale fertilizer production requires scaling up the culture to larger volumes, which is not cost-effective with currently available options for growth media. In this study, we tested a seawater-based, cost-effective alternative to the commonly used nutrient-rich culture medium for the growth of this bacterium. We found that reducing salinity from 3% to 1.2% had no adverse effects on its heterotrophic growth, dry cell yield, nitrogen content, and total amino acid composition. The nitrogen content and the weight percent of free lysine, aspartic acid, and glutamate increased in the biomass obtained from cultures grown at 1.2% salinity. Under autotrophic conditions, decreasing salinity to 1.2% did not affect cell growth, final dry cell yields, and total carbon assimilation, but N assimilation tended to be higher. Reducing salinity to 1.2% proved to be cost-effective and feasible for the cultivation of R. sulfidophilum without increasing the risk of contamination, providing a viable alternative for its large-scale cultivation and application as a plant nitrogen fertilizer.

microbiology↗

Synthetic peptide-induced internalization of biomolecules into various plant and algal cells via micropinocytosis

Efficient intracellular delivery of biomolecules is important for many different biological and biotechnological applications in living organisms, and is a prerequisite for certain types of fundamental and applied research. One major challenge is the delivery of unmodified, functional cargoes in a simple, time-efficient, and high-throughput manner. Herein, we present an efficient strategy that uses fusion peptides containing cell penetrating peptide, endosomal escape domain, and a sarcosine linker to introduce biomolecules, namely fluorescent protein and dextran, via macropinocytosis into the cells of various land plants and microalgae. Our peptide-mediated delivery system allows for high-throughput delivery of functional biomolecules within a few minutes to a few hours as well as open new possibilities for biology and biotechnology using difficult-to-transfect cell types.

plant biology↗

Efficient callus induction and completion of regeneration in kenaf Hibiscus cannabinus

Kenaf, Hibiscus cannabinus, is a fiber-enriched plant belonging to Malvaceae and is an important fiber crop. The features of kenaf of being fast-growing and fiber-enriched suggest the potential for the use of kenaf in biomass and materials; however, the complete regeneration procedure, which is essential for genetic modification, is lacking. Here, we report the complete regeneration of kenaf from cotyledon explants achieved by callus induction on an improved callus-inducing medium and shoot induction on a shoot-inducing medium and by seed setting under a regulated growth condition in a chamber. Our complete regeneration method will enable the production of stably transformed kenaf that can improve the properties of kenaf as a material.

plant biology↗