Photostability of Isovaline and its Precursor 5-Ethyl-5- methylhydantoin Exposed to Simulated Space Radiations

نویسندگان

  • Palash K. Sarker
  • Jun-ichi Takahashi
  • Yukinori Kawamoto
  • Yumiko Obayashi
  • Takeo Kaneko
  • Kensei Kobayashi
چکیده

Aqueous solutions of isovaline and its precursor molecule, 5-ethyl-5-methylhydantoin, were irradiated with ultraviolet and γ-ray photons, to evaluate their structural stability against space radiation. The degree of photolysis was measured and irradiation products were identified using chiral, reversed-phase and ion-exchange high-performance liquid chromatography. The experimental results show that the degree of photolysis of 5-ethyl-5-methylhydantoin is more significant than that of isovaline under ultraviolet light irradiation, while the results under γ-ray irradiation are the opposite. As the products of isovaline photolysis, aspartic acid, serine, glutamic acid and alanine were dominantly detected.

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عنوان ژورنال:

دوره 13  شماره 

صفحات  -

تاریخ انتشار 2012