토마토 주스를 Sep-pak $C_{18}$ cartridge를 이용하여 ascorbate 및 phenolic 획분으로 분리하여 NDMA 생성 억제 효과를 시험하였다. 시료의 첨가량이 많을수록 NDMA 억제 효과가 비례적으로 증가하여 ascorbate 획분은 최고 $81.37{pm}0.25%$, phenolic 획분은 $72.03{pm}0.25%$였다. Phenolic 획분을 prep-HPLC로 4개의 fractions으로 분취하여 NDMA 생성 억제 효과를 실험한 결과 fraction 2에서 활성이 가장 높았으며, fraction 2를 다시 4개의 subfractions으로 재분취하여 활성실험을 한 결과 subfraction 2b의 획분에서 최대 억제율이 pH 1.2에서 $70.62{pm}0.45%$ 및 pH 4.2에서 $75.30{pm}0.45%$였다. 그래서 subfraction 2b를 분리, 정제한 후 GC-Mass 및 $^1H-NMR$과 $^{13}C-NMR$로 동정한 결과 phenolic acid의 일종인 o-coumaric acid임을 확인할 수 있었다.
A tomato (Lycopersicon esculentum cv. Naomi F1) juice was separated into ascorbate and phenolic portions using a Sep-pak $C_{18}$ cartridge, and its each portion was tested for inhibition of N-nitrosodimethylamine (NDMA) formation. Ascorbate and phenolic portions of tomato juice inhibited NDMA formation by $81.37{pm}0.25%$ and $72.03{pm}0.25%$, respectively. The phenolic portion was further fractionated by prep-HPLC and inhibitory effects of NDMA formation by 4 fractions $(1{sim}4)$ from tomato juice was tested under the different pH conditions (pH 1.2 and 4.2). Fraction 2 inhibited NDMA formation by $50.10{pm}0.46%$ (pH 1.2) and $64.30{pm}0.20%$ (pH 4.2), respectively. Fraction 2 was further separated into 4 subfractions $(2a{sim}2d)$. Subfraction 2b especially inhibited NDMA formation by $70.62{pm}0.45%$ (pH 1.2) and $75.30{pm}0.45%$ (pH 4.2). This subfraction was confirmed o-coumaric acid through the analysis of GC-Mass spectrum, $^1H-NMR$ and $^{13}C-NMR$.
