Institute for Agro-Environmental Sciences, NARO

Environmental Biofunction Unit

Mulch film is highly essential in vegetable production. However, after harvesting, the recovery and recycling of used non-degradable mulch films would require a lot of energy and are labor intensive. To address this labor problem, recently Japan has begun using biodegradable plastic (BP) mulch films. After harvest, the incompletely deteriolated BP mulch films at the field are plowed into soil where they are completely degraded by soil microbial activity. In this way, BP mulch films is considered as a new labor-saving technique which will enable farmers to engage in large scale farming. However, since these BPs are degraded by microorganisms, adequate degradation would require specific conditions of temperature and humidity. Sometimes its degradation is too fast and sometimes insufficient for plowing-down after use. We aimed at controlling the activity of BP degrading enzymes in natural environment.

Unit Leader

Research Topics : Increase the enzyme productivity and biofunction of enzyme

Unit Members

Research Topics
Ken SUZUKI Principal Researcher Analysis of characteristics and structure of enzymes
Kimiko YAMAMOTO-TAMURA Principal Researcher Characterization of BP-degradation activity and microflora of agricultural soil
Shun TSUBOI Researcher


Research Publications

  • Koitabashi M, Sameshima-Yamashita Y, Watanabe T, Shinozaki Y, Kitamoto H (2016) Phylloplane fungal enzyme accelerate decomposition of biodegradable plastic film in agricultural settings. Japan Agricultural Research Quarterly 50: 329-324
  • Watanabe T, Morita T, Koike H, Yarimizu T, Shinozaki Y, Sameshima-Yamashita Y, Yoshida S, Koitabashi M, Kitamoto H (2016) High-level recombinant protein production by the basidiomycetous yeast Pseudozyma antarctica under a xylose-inducible xylanase promoter. Appl Microbiol Biotechnol 100(7): 3207-3217
  • Yamamoto-Tamura K, Hiradate S, Watanabe T, Koitabashi M, Sameshima-Yamashita Y, Yarimizu T, Kitamoto H (2015) Contribution of soil esterase to biodegradation of aliphatic polyester agricultural mulch film in cultivated soils. AMBExpress
  • Ueda H, Mitsuhara I, Tabata J, Kugimiya S, Watanabe T, Suzuki K, Yoshida S, Kitamoto H (2015) Extracellular esterases of phylloplane yeast Pseudozyma antarctica induce defect on cuticle layer structure and water-holding ability of plant leaves. Appl Microbiol Biotechnol 99: 6405-6415
  • Suzuki K, Noguchi MT, Shinozaki Y, Koitabashi M, Sameshima-Yamashita Y, Yoshida S, Fujii T, Kitamoto HK (2014) Purification, characterization, and cloning of the gene for a biodegradable plastic-degrading enzyme from Paraphoma-related fungal strain B47-9. Appl Microbiol Biotechnol 98: 4457-4465