Proceedings of the Takasaki symposium on radiation application of natural polymers in Asia

This Takasaki symposium was annually held as the 3rd meeting for radiation processing of natural polymers through research cooperation among Asian countries. The symposium includes the presentations of research outcomes on radiation processing of starches, silk proteins and marine carbohydrates. In the researches of starch and cellulose, radiation crosslinking of biodegradable polysaccharides was achieved by modifying it to be water-soluble paste, showing the wide range of its application to wound dressing and biodegradable plastics. In silk protein researches, pulverization and water-solubilization of the irradiated silk proteins and its antibacterial properties were reported. In the researches of marine carbohydrates, it was reported that radiation-degraded chitosan and alginate showed promotion effects for plant growth, enhancement of antibacterial properties, and capability to be applied for bioadhesive materials. In addition, in estimation of economic scale of radiation application, comparisons between Japan and U.S. in medical, agricultural and industrial fields were introduced. Many domestic and foreign attendants were very interested in reports and exchanged their opinions actively. Radiation application of natural polymers are the most important subjects from the view points of resource recycling and environment protection and are good agreement with the needs of Asian countries. Outcomes of this symposium are expected to contribute the progress in radiation applications in south Asian countries as well as Japan. In the symposium we had the 63 participants consisted of 16 foreign researchers from not only bilaterally cooperated Malaysia, Thailand and Vietnam, but also Indonesia and China, 28 from domestic universities, governmental institutes and companies, and 32 from JAERI. This proceeding compiles the invited and contributed papers. The 22 of the presented papers are indexed individually. (J.P.N.)