RESUMO
Plant hormones act as important signaling molecules that regulate responses to abiotic stress as well as plant growth and development. Because their concentrations of hormones control the physiological responses in the target tissue, it is important to know the distributions and concentrations in the tissues. However, it is difficult to determine the hormone concentration on the plant tissue as a result of the limitations of conventional methods. Here, we report the first multi-imaging of two plant hormones, one of cytokinin [i.e., trans-zeatin (tZ)] and abscisic acid (ABA) using a new technology, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) imaging. Protonated signals of tZ (m/z 220.1) and ABA (m/z 265.3) were chosen on longitudinal sections of rice roots for MS imaging. tZ was broadly distributed about 40 mm behind the root apex but was barely detectable at the apex, whereas ABA was mainly detected at the root apex. Multi-imaging using MALDI-TOF-MS enabled the visualization of the localization and quantification of plant hormones. Thus, this tool is applicable to a wide range of plant species growing under various environmental conditions.
Assuntos
Ácido Abscísico/metabolismo , Citocininas/metabolismo , Oryza/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Transporte Biológico , Oryza/química , Raízes de Plantas/metabolismoRESUMO
Two new isoflavanones, eryvarins Y (1) and Z (2), together with three known compounds (3-5) were isolated from the roots of Erythrina variegata. The structures of 1 and.2 were established on the basis of spectroscopic data. The new compounds are peculiar isoflavanones, possessing both a 3-methylbut-2-en- 1-yl group and a 2-hydroxy-3-methylbut-3-en-1-yl group. Among the isolates, orientanol E (5) exhibited potent antibacterial activity against methicillin- resistant Staphylococcus aureus (MRSA) strains.
Assuntos
Erythrina/química , Isoflavonas/química , Raízes de Plantas/química , Antibacterianos/farmacologia , Isoflavonas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura MolecularRESUMO
A novel isoflavone, erythgianin A (1), along with nine known compounds 2-10, was isolated from the stem bark of Erythrina poeppigiana (Leguminosae). The unusual isoflavone structure of 1, possessing a highly oxidized 3â³,4â³-dihydroxy-2â³-hydroxymethyl-2â³-methyl-2â³,3â³-dihydropyrano substituent, was determined on the basis of spectroscopic analyses. All of the isolated compounds were evaluated for their in vitro inhibitory activity toward human glyoxalase I. Among the isolates, isolupalbigenin (10) with two prenyl groups showed the highest inhibitory activity.
