Biomolecular Chemistry Laboratory (Niichiro Koga Laboratory)

Our laboratory studies the in vivo roles of ceramides (such as glucosylceramide and ceramides) that enhance the skin's barrier function and provide moisturizing effects when ingested as a health food or applied as a cosmetic ingredient, and cocoa protein (protein derived from cocoa beans) that increases beneficial bacteria such as butyrate-producing bacteria and improves bowel movements. We also conduct applied research in collaboration with companies to commercialize these health and beauty ingredients.
I teach lectures and experiments in subjects such as basic microbiology for first-year students, applied food microbiology and food science for second-year students, food science experiments for third-year students, and microbiological utilization for Graduate School. I focus on explaining applications in industry, making it easy for students to visualize how what they are learning will be used in the workplace.

Joint research with a company on the “health effects of consuming high-cocoa chocolate”

High-cacao chocolate refers to chocolate that contains a high amount of cacao bean components, such as CACAO72, CACAO86, and Cacao70, which are the raw materials for chocolate. In a joint research project with Meiji Co., Ltd., our laboratory was the first in the world to discover that cacao protein (protein contained in cacao beans) contained in high-cacao chocolate improves the intestinal environment and promotes bowel movements.1^{, 2)} Furthermore, it was found that consuming high-cacao chocolate increased the amount of intestinal bacteria that produce butyrate (a short-chain fatty acid), which is expected to suppress colorectal cancer, prevent inflammatory bowel disease (IBD), and prevent diabetes in the human gut.2⁾ This discovery was covered by numerous media outlets, including NHK General's "Asaichi," the Mainichi Shimbun, the Asahi Shimbun, and the Nikkei Shimbun. As a result, high-cacao chocolate became a huge hit, and even today, confectionery aisles are bustling with high-cacao chocolate products.

“Elucidation of the physiological effects of plant ceramides and their effective use as sustainable materials”

Plant ceramides consist of two types: glucosylceramide and ceramide. When ingested, they are known to have skin moisturizing effects and preventive effects against colorectal cancer. Our laboratory has established a new analytical and quantitative method for plant ceramides using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), which had previously been considered difficult. Furthermore, we have revealed for the first time in the world that an enzyme called glucocerebrosidase, which converts glucosylceramide to ceramide, is widely present in seed plants and is involved in the drought tolerance of plants.3⁾ In joint research with Meiji Co., Ltd., using this latest LC-ESI-MS/MS analytical technology, we discovered that the cocoa husk (seed coat), an unused part of the cocoa bean used as a raw material for chocolate, contains far more ceramide than other plants.4⁾ A ceramide chocolate called "Cacao Beaute," which contains this cocoa husk ceramide, has been launched nationwide. Because cacao husk ceramide is expected to significantly reduce extraction and manufacturing costs, it is anticipated to be used as a sustainable ingredient in a variety of foods and cosmetics other than chocolate.

1.  Koga J. et al.（2022）Curr. Dev. Nutr. 6, nzac129
2.  Ito H. et al.（2025）Biosci. Microbiota Food Health 44, 196–204
3.  Koga J. et al.（2021）J. Biol. Chem. 297, 101236
4.  Yaita Y. and Sato Y. et al.（2026）Biosci. Biotech. Biochem. 90, 257–260