Mohana Kumara Patel, Srimany Amitava, Arunan Suganya, Ravikanth Gudasalamani, Uma Shaanker Ramanan, Pradeep Thalappil
DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600036, India.
School of Ecology and Conservation, Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bengaluru, 560065, India.
PLoS One. 2016 Jun 30;11(6):e0158099. doi: 10.1371/journal.pone.0158099. eCollection 2016.
Ambient ionization mass spectrometric imaging of all parts of the seedling of Dysoxylum binectariferum Hook. f (Meliaceae) was performed to reconstruct the molecular distribution of rohitukine (Rh) and related compounds. The species accumulates Rh, a prominent chromone alkaloid, in its seeds, fruits, and stem bark. Rh possesses anti-inflammatory, anti-cancer, and immuno-modulatory properties. Desorption electrospray ionization mass spectrometry imaging (DESI MSI) and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) analysis detected Rh as well as its glycosylated, acetylated, oxidized, and methoxylated analogues. Rh was predominantly distributed in the main roots, collar region of the stem, and young leaves. In the stem and roots, Rh was primarily restricted to the cortex region. The identities of the metabolites were assigned based on both the fragmentation patterns and exact mass analyses. We discuss these results, with specific reference to the possible pathways of Rh biosynthesis and translocation during seedling development in D. binectariferum.
对双翅果杜英（楝科）幼苗的各个部分进行了常压电离质谱成像，以重建洛石碱（Rh）及相关化合物的分子分布。该物种在其种子、果实和茎皮中积累了Rh，一种显著的色酮生物碱。Rh具有抗炎、抗癌和免疫调节特性。解吸电喷雾电离质谱成像（DESI MSI）和电喷雾电离（ESI）串联质谱（MS/MS）分析检测到了Rh及其糖基化、乙酰化、氧化和甲氧基化类似物。Rh主要分布在主根、茎的颈环区域和幼叶中。在茎和根中，Rh主要局限于皮层区域。基于碎片模式和精确质量分析确定了代谢物的身份。我们讨论了这些结果，并特别提及了双翅果杜英幼苗发育过程中Rh生物合成和转运的可能途径。
