Our Research

Foods have both chemical tastes such as "salty" and "sweet" as well as physical tastes such as "soft" and "tough. In fact, it is said that more than half of the "taste" of a food is determined by its physical taste. Therefore, the technology to control the physical taste of food is extremely important.

However, many foods are made of biopolymers or combinations of biopolymers and cells, and because these composite materials are in a non-equilibrium state, their physical taste (as well as chemical taste) changes not only with processing conditions but also with time since they were produced. This is a very troublesome (and at the same time interesting) property, and one of the issues that must be solved to achieve the production of food products with good reproducibility.

Therefore, our research aims to systematically investigate the relationship between processing conditions and rheological properties of jelly-like foods as time-series data in order to establish a technique to control the physical taste of foods with good reproducibility.

The tissues and organs in our bodies are huge aggregates of cells and extracellular matrix with a complex hierarchical structure. The hierarchical structure of tissues and organs is related to their functions. A tissue or organ is made up of billions to hundreds of billions of cells, and the maintenance of these cells requires sufficient oxygen and nutrients delivered by the bloodstream. Therefore, to construct functional regenerative tissues, it is necessary to establish a method to deploy a vascular network that serves as a transport pathway for oxygen and nutrients, while reproducing the hierarchical structure of tissues and organs.

We have discovered in our laboratory that a collagen gel with a multivessel structure (multichannel collagen gel: MCCG) is formed when an aqueous collagen solution is dialyzed in phosphate buffer solution (Furusawa et al., Biomacromolecules, 13, 2012, 29-39). The multichannel structure of MCCG very well mimics the branching structure of blood vessels in vivo. Observation with a polarizer also shows that MCCG has birefringence. This indicates that the collagen fibers that make up the MCCG are oriented. Therefore, we can say that MCCG is a material with a complex hierarchical structure that has both collagen fiber orientation and a biomimetic multichannel structure. Furthermore, since collagen is the main component of the extracellular matrix, cells can adhere to it without special surface treatment. We believe that MCCG can be used as a cell scaffold material to reproduce the hierarchical structure of tissues and organs while deploying oxygen and nutrient transport pathways.

We already have the technology to construct regenerative tissues with complex hierarchical structures. So, what can we achieve by combining these regenerative tissues? For example, if we could create a small regenerative brain with the same functions as a brain, what would happen if we combined it with regenerative muscle tissue or a regenerative heart? Is it just a collection of cells and biomacromolecules? Our current research is approaching the fundamental question of biology, "What is a living thing? What is a living thing?