Gyeong Han Jeonga, Jae-Hyeon Chob, Cheorun Joc, Sungbeom Leed, Seung Sik Leed,Hyoung-Woo Baid, Byung Yeoup Chungd,*, Tae Hoon Kima,*
aDepartment of Food Science and Biotechnology, Daegu University, Gyeongsan 38453, Republic of Korea
bInstitute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Republic of Korea
cDepartment of Agricultural Biotechnology and Research Institute of Agriculture and Life Science, Seoul National University, Seoul 08826, Republic of Korea
dAdvanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), Jeongeup 56212, Republic of Korea
* Corresponding authors : Tae Hoon Kim, Byung Yeoup Chung
Abstract
Radiation is a promising technique for improving the safety and shelf-life of processed foods. In the present investigation, the degradation mechanism and bioactivity improvement of rosmarinic acid (RA) were studied in response to various gamma irradiation doses (10, 20, and 50 kGy). RA exposed to gamma irradiation at 50 kGy was completely degraded and showed an increased inhibitory effect against 3T3-L1 preadipocyte compare to the parent compound. Structures of the newly generated compounds 2-4 from irradiated RA at 50kGy were elucidated based on spectroscopic methods, including 1H nuclear magnetic resonance (NMR) and mass spectrometry (MS). Interestingly, compounds 2 and 5 exhibited significantly enhanced anti-adipogenic properties in 3T3-L1 cells compared to the original compound. These results provide evidence that structural changes in RA induced by gamma irradiation might enhance biological efficacy.
Keywords : Polyphenols, Rosmarinic acid, Gamma-irradiation, Anti-adipogenic compounds, 3T3-L1 preadipocytes