가중나무를 2013년 전라북도 전주 인근 야산에서 수집하여 음건한 후 methanol(MeOH)로 추출하고, 감압농축건조한 추출물을 유채(Brassica napus L.)를 대상으로 in vitro에서 seed bioassay를 수행한 결과 식물생장을 50% 억제하는 식물생장억제값(GR<SUB>50</SUB>)은 739 μg g<SUP>-1</SUP>이었다. 식물생장을 억제하는 생리활성물질을 분리하기 위하여 MeOH 추출물을 hexane, CH₂Cl₂, EtOAc, butanol, H₂O로 순차분획하고 GR<SUB>50</SUB>을 조사한 결과 EtOAc 분획물의 억제효과가 가장 컸으며(561 μg g<SUP>-1</SUP>), EtOAc 분획물을 thin layer chromatography와 column chromatography로 5개의 분리물로 분리하고, 식물생장억제효과를 검정한 결과 EAC 분획물이 가장 높은 억제효과를 나타냈다(GR<SUB>50</SUB> 50 μg g<SUP>-1</SUP>). EAC 분리물을 gas chromatograph mass spectrometry로 분석한 결과 molecular ion (M+)이 m/z 117이고 fragmentaion은 m/z 116, 100, 72, 58이었다. EAC 분리물의 ¹H-NMR(nuclear magnetic resonance)분석결과 δ (ppm)에서 3.30 (9H, d, H-2, 3, 4), 3.85 (2H, s, H-1)에서 proteon signal을 확인하였으며, <SUP>13</SUP>C-NMR 분석결과 δ (ppm)은 52.39 (C-3, 3", 3""), 65.86 (C-2), 167.32 (C-1)에서 carbon signal을 확인하였다. GCMS, ¹H-NMR, <SUP>13</SUP>C-NMR의 분석결과 가중나무 EAC 분리물의 화학명은 1-carboxy-N,N,N-trimethyl이고, 일반명은 glycine betaine으로 확인되었다. Glycien betaie 화합물을 구입하여 유채(Brassica napus L.)를 대상으로 in vitro에서 seed bioassay를 수행한 결과 GR50값은 91 μg g<SUP>-1</SUP>으로 EAC 분리물의 GR<SUB>50</SUB>값과 유사하였다.
Objective of this study is to discover new herbicide parent mother compound(s) from native plants in Korea. The leaves of Ailanthus altissima Swingle were collected in Jeonju, Jeollabukdo in 1995. The shade dried and powdered plant samples were extracted with methanol (MeOH). The methanol extract of A. altissima was subjected to in vitro seed bioassay on rapeseed (Brassica napus L.). The results indicated that the methanol extract significantly inhibited the germination of rapeseed with the GR<SUB>50</SUB> (growth retardation 50%) value of 739 μg g<SUP>-1</SUP>. In order to isolate the bioactive substances that inhibit plant growth, the MeOH extract was sequentially fractionated with hexane, dichloromethane, ethyl acetate, butanol, and H₂O. Among them, the EtOAc fraction showed the lowest GR<SUB>50</SUB> value (561 μg g<SUP>-1</SUP>) than other fractions. The EtOAc fraction was further fractionated on column chromatography, which showed 5 fractions (EAA-EAE) with good plant growth inhibitory effect. In these, the EAC fraction showed the highest inhibitory effect (GR<SUB>50</SUB> at 50 μg g<SUP>-1</SUP>). The gas chromatography and mass spectrometry analysis of EAC fraction revealed that molecular ion (M<SUP>+</SUP>) was m/z 117 and fragment ions were m/z 116, 100, 72, and 58. Based on the results obtained from GC-MS, ¹H-NMR, and <SUP>13</SUP>C-NMR analyses, the EAC fraction was identified as 1-carboxy-N,N,N-trimethyl, and its common name was glycine betaine. The seed bioassay of glycine betain results revealed that the GR<SUB>50</SUB> value was 91 μg g<SUP>-1</SUP>, which was comparable with the GR<SUB>50</SUB> value of the EAC fraction of A. altissima.