Mon, 28 Nov 2022
Events, Seminar Series

Dr. Shinsuke Ifuku

Tottori University

Chitin nanofiber: various biological functions of the new material from crab shells and its practical application

Wednesday, November 28, 2022
SSB 7172 @ 10:30 a.m.

Hosts: Drs. Byron Gates and Bonnie Gray


Presenting Author’ Biography

Dr. Shinsuke IFUKU is a professor in the Department of Applied Chemistry, Graduate School of Engineering, Tottori University, a national university in Japan. His research is based on chemistry, polymer chemistry, and materials science, specializing in polymeric biomaterials. since his arrival at Tottori University, Dr. Ifuku has been working on the effective utilization of crab shells, a local specialty, by converting its main component, the polysaccharide, chitin into nanofibers and revealing their numerous functions. He received his PhD in Agriculture from Kyoto University in Japan in 2005, and after a postdoctoral fellowship at the University of British Columbia, Canada, in 2007, he joined Tottori University in 2008. In 2016, he started Marine Nanofiber Co. Ltd., a university venture for the practical application of chitin nanofibers. He also serves as the president of the company. More than 70 health care products containing chitin nanofibers have been sold. He has published about 150 peer-reviewed original papers related to chitin, which have been cited about 5000 times and obtained an h-index of 33. He has received numerous awards from the Ministry of Education, Culture, Sports, Science and Technology and from his affiliated national societies related to chemistry, polymers, fibers, and carbohydrate polymers.

1 Tottori University, 4-101 Koyama-cho Minami, Tottori 680-8552, Japan           

Graphical Abstract


Chitin is a polysaccharide composed of linear chains of N-acetylglucosamine units. It is found in the exoskeletons of crabs, shrimp, and insects, and in the cell walls of fungi and mushrooms. It is the second most abundant biomass resource after cellulose, but its use is limited. The reason, chitin is insoluble in solvents, making it difficult to process. We have successfully morphologically converted chitin derived from crab shells into nanofibers by mechanical pulverization [1]. Chitin nanofibers are 10 nm wide and can be dispersed uniformly in water and can be processed into various forms by dehydration operations [2]. So far, processed forms such as sheets, films, threads, and sponges have been obtained. This method can now be applied to produce similarly shaped nanofibers from shrimp shells, insects, and mushrooms. In addition, experiments using cells and animals have become easier, and various functions related to health care have been revealed. For example, when applied to the skin, they have wound-healing, inflammation-relieving, and hair-growing effects [3]. When taken, it also improves intestinal inflammation, relief of fatty hepatitis, [4] reduces weight, and affects the intestinal microflora. When applied to plants, it promotes growth and activates immunity. Chitin nanofibers are crystalline polymers and have excellent mechanical properties. Therefore, it can be used as a reinforcing filler to strengthen materials. When blended in resins, it improves mechanical strength and significantly reduces thermal expansion [5]. In addition, the transparency of the resin is not impaired due to the nano-size effect. This is because visible light was not scattered at the interface between the resin and nanofibers. In 2016, the author launched a university-launched venture, Marine Nanofiber Inc. to promote the use of the new material that is a waste material but has various functions. The company manufactures and sells nanofibers as functional raw materials. The company has commercialized more than 70 health care-related cosmetics and health foods containing chitin nanofibers. Since chitin nanofibers can be produced from wastes such as crustacean and insect hulls, fermentation residues, and inedible parts of mushrooms, their widespread use can contribute to the realization of a sustainable, recycling-oriented society. To this end, we must continue to explore the potential functions of chitin nanofibers and clarify their applications.

Keywords: chitin nanofiber; crab shell; biological properties; reinforcement filler; commercialization.


1.        S. Ifuku, M. Nogi, K. Abe, M. Yoshioka, M. Morimoto, H. Saimoto, H. Yano, Biomacromolecules, 2009, 10, 1584.
2.        J. Yao, W. Fang, J. Guo, D. Jiao, S. Chen, S. Ifuku, H. Wang, A. Walther,  Biomacromolecules, 2020, 21, 2176.
3.        K. Azuma, R. Koizumi, H. Izawa, M. Morimoto, H. Saimoto, T. Osaki, N. Ito, M. Yamashita, T. Tsuka, T. Imagawa, Y. Okamoto, T. Inoue, S. Ifuku, International Journal of Biological Macromolecules, 2019, 126, 11.
4.        M. Goto, D. Iohara, A. Michihara, S. Ifuku, K. Azuma, D. Kadowaki, T. Maruyama, M. Otagiri, F. Hirayama, M. Anraku, International Journal of Biological Macromolecules, 2020, 164 659.
5.        S. Ifuku, S. Morooka, A. N. Nakagaito, M. Morimoto, H. Saimoto, Green Chemistry, 2011, 13, 1708.