Profile of cryptobrachytone C accumulation in Cryptocarya pulchrinervia leaves using MALDI-MSI

Ratnasari J, Esyanti RR, Tan MI, Juliawaty LD, Shimma S. 2021. Profile of cryptobrachytone C accumulation in Cryptocarya pulchrinervia leaves using MALDI-MSI. Biodiversitas 22: 1172-1178. Cryptobrachytone C is an active compound isolated from leaves of Cryptocarya pulchrinervia, an indigenous plant from Indonesia. Cryptobrachytone C is cytotoxic against P388 leukemia cancer cell lines. A profile of cryptobrachytone C accumulation in leaves based on physiological age is necessary to study cryptobrachytone C production in the plant since it has anticancer potential. In situ profiling of cryptobrachytone C accumulation in leaves was carried out by imaging techniques using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). The cryptobrachytone C ionization efficiency was carried out by derivatization using Girard-T reagent and coating with α-cyano-4-hydroxycinnamic acid (α-CHCA) matrix. Scanned leaves show higher accumulation intensity in the second leaf. Quantitative accumulation profiling was conducted using GC-MS, where the highest amount of cryptobrachytone C was on the second leaf at 87.07 ± 47.21 mg. This showed that the most effective isolation of cryptobrachytone C would be obtained from young leaves of Cryptocarya pulchrinervia. This profile would play a role in cryptobrachytone C production in-situ or ex-situ using tissue culture.

High resolution1H and13C NMR and mass spectral studies of substituted dipyridylpyridazine

Total assignment of the1H and13C NMR spectra of 3,6-bis(2'-pyridyl)pyridazine derivatives (n-dppn) have been recorded at 400 and 100 MHz, respectively.1Based on these data, the complete assignment of the13C NMR chemical shift values was made by a13C{1H} decoupling. The spectra clearly show that then-dppn ligands exist in thecis–cisconformation at least in solution. Matrix assisted laser desorption ionization (MALDI) and time-of-flight mass spectrometry (TOFMS) are used to record the mass spectra of then-dppn ligands. α-Cyano-4-hydroxycinnamic acid (CHCA) matrix promoted the molecular ion detection when 180 pmol ofn-dppn is introduced into the TOFMS.