TY - JOUR
T1 - In vivo analysis and spatial profiling of phytochemicals in herbal tissue by matrix-assisted laser desorption/ionization mass spectrometry
AU - Ng, Kwan Ming
AU - LIANG, Zhitao
AU - Lu, Wei
AU - Tang, Ho Wai
AU - ZHAO, Zhongzhen
AU - Che, Chi Ming
AU - Cheng, Yung Chi
N1 - Funding support from the University Development Fund of The University of Hong Kong, Dean’s Fund of Li Ka Shing Faculty of Medicine, Small Project Funding from the Committee on Research and Conference Grants(CRCG), and the University Grants Committee of the Hong Kong SAR of China (Area of Excellence Scheme, AoE/P -10/01) are gratefully acknowledged.
PY - 2007/4/1
Y1 - 2007/4/1
N2 - Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was developed for spatial profiling of phytochemicals and secondary metabolites in integrated herbal tissue without solvent extraction. Abundant alkaloid ions, including (+)-menisperine (m/z 356), magnoflorine (m/z 342), stepharanine (m/z 324), protonated sinomenine (m/z 330), protonated sinomendine (m/z 338), and a metabolite at m/z 314, could be directly desorbed from α-cyano-4- hydroxycinnamic acid- (CHCA-) coated stem tissue of Sinomenium acutum upon N2 laser (337 nm) ablation, while the ion signals desorbed from sinapinic acid- (SA-) coated and 2,5-dihydroxybenzoic acid- (DHB-) coated stem tissue were at least 10 times weaker. Solvent composition in the matrix solution could have significant effects on the ion intensity of the metabolites. Under optimized conditions that maximize the ion intensity and form homogeneous matrix crystals on the tissue surface, spatial distributions of the metabolites localized in different tissue regions, including cortex, phloem, xylem, rim, and pith, and their relative abundances could be semiquantitatively determined. The three metabolites detected at m/z 356, 342, and 314 showed specific distributions in the herbal samples collected from different growing areas, while others were not. By applying principal component analysis (PCA), the characteristic metabolites in specific tissue regions could be easily determined, allowing unambiguous differentiation of the herbal samples from different geographic locations.
AB - Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) was developed for spatial profiling of phytochemicals and secondary metabolites in integrated herbal tissue without solvent extraction. Abundant alkaloid ions, including (+)-menisperine (m/z 356), magnoflorine (m/z 342), stepharanine (m/z 324), protonated sinomenine (m/z 330), protonated sinomendine (m/z 338), and a metabolite at m/z 314, could be directly desorbed from α-cyano-4- hydroxycinnamic acid- (CHCA-) coated stem tissue of Sinomenium acutum upon N2 laser (337 nm) ablation, while the ion signals desorbed from sinapinic acid- (SA-) coated and 2,5-dihydroxybenzoic acid- (DHB-) coated stem tissue were at least 10 times weaker. Solvent composition in the matrix solution could have significant effects on the ion intensity of the metabolites. Under optimized conditions that maximize the ion intensity and form homogeneous matrix crystals on the tissue surface, spatial distributions of the metabolites localized in different tissue regions, including cortex, phloem, xylem, rim, and pith, and their relative abundances could be semiquantitatively determined. The three metabolites detected at m/z 356, 342, and 314 showed specific distributions in the herbal samples collected from different growing areas, while others were not. By applying principal component analysis (PCA), the characteristic metabolites in specific tissue regions could be easily determined, allowing unambiguous differentiation of the herbal samples from different geographic locations.
UR - http://www.scopus.com/inward/record.url?scp=34247092007&partnerID=8YFLogxK
U2 - 10.1021/ac062129i
DO - 10.1021/ac062129i
M3 - Journal article
C2 - 17313187
AN - SCOPUS:34247092007
SN - 0003-2700
VL - 79
SP - 2745
EP - 2755
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 7
ER -