Long-Ze Lin

Liquid chromatography–electrospray mass spectrometric analysis of curcuminoids and sesquiterpenoids in turmeric (Curcuma longa)

On-line high-performance liquid chromatography–UV diode-array and electrospray mass spectrometry have been used simultaneously to analyze curcuminoids and sesquiterpenoids in a fresh turmeric (Curcuma longa) extract. Five major components: curcumin (1), demethoxycurcumin (2), bisdemethoxycurcumin (3), ar-turmerone (5) and curlone (6) have been unambiguously identified, based on their UV spectra, mass spectra and retention times in comparison with the data of standard compounds. This method provides a reliable fingerprint for turmeric, distinguishing it from other Curcuma species.

Liquid chromatographic–electrospray mass spectrometric study of the phthalides of Angelica sinensis and chemical changes of Z-ligustilide

Abstract High-performance liquid chromatography–electrospray ionization–mass spectrometry has been applied to analyze the chemical constituents of Danggui (the rhizome of Angelica sinensis) and to study chemical changes of Z-ligustilide. Twelve phthalides were unambiguously identified as senkyunolide I (3), senkyunolide H (4), sedanenolide (8), butylphthalide (9), E-ligustilide (13), Z-ligustilide (14), Z-butylidenephthalide (15), Z,Z′-6.8′,7.3′-diligustilide (16), angelicide (17), levistolide A (18), Z-ligustilide dimer E-232 (19) and Z,Z′-3.3′,8.8′-diligustilide (20) in Danggui extract. The existence of 12 other phthalides (2, 5–7, 11, 12, 22–27), ferulic acid (1) and coniferyl ferulate (10) in Danggui extract has also been demonstrated. Phthalides 3, 4, 16–18 and 20 were determined to be the products from chemical change of Z-ligustilide. This is the first report of the existence of 16 compounds (2–8, 10–12, 20, 22–25 and 27) in Danggui extract.

High-performance liquid chromatography–electrospray mass spectrometric analysis of pungent constituents of ginger

Abstract A gradient elution reversed-phase HPLC separation of ginger extract has been developed, which gives better separation than previous isocratic separations. HPLC–UV–electrospray MS has been successfully utilized to identify the individual pungent constituents in the chromatogram of ginger extract. Seven compounds were positively identified as the major pungent constituents of ginger based on their UV spectra, [M+H] + , [M+Na] + and characteristic sodiated dimer [2M+Na] + ions, and comparison to data for the purified standards: [6]-gingerol and [6]-shogaol. The pungent compounds were assigned as [6]-gingerol, [8]-gingerol, [10]-gingerol, [6]-shogaol, [8]-shogaol, [10]-shogaol and [6]-gingediol. Another eight minor compounds were tentatively identified as gingerol analogues.

Analysis of alkamides in roots and achenes of Echinacea purpurea by liquid chromatography–electrospray mass spectrometry

Abstract High-performance liquid chromatography paired with UV photodiode-array and electrospray mass spectrometry was investigated as a method for the analysis of alkamides in the roots and achenes of the popular herb Echinacea purpurea (L.) Moench. All alkamides showed very abundant peaks in the reconstructed total ion current chromatogram. Nine alkamides were identified in the root of E. purpurea, similar to the fingerprint reported by Bauer and Remiger [Planta Med., 55 (1989) 367]. Several minor alkamides, not identifiable by previously published techniques, have been also tentatively identified. Two major peaks were identified in E. purpurea achenes as undeca-2E,4Z-diene-8, 10-diynoic acid isobutylamide (1) and dodeca-2E,4E,8E,10E/Z tetraenoic acid isobutylamide (8/9). The isomer pair, tetraene 8/9, was purified as a standard for quantification of alkamide content in E. purpurea achenes and roots, as well as for the achenes of E. angustifolia DC and E. pallida (Nutt.) Nutt.

Lycorine alkaloids from Hymenocallis littoralis

From Hymenocallis littoralis, one new alkaloid, named littoraline, together with 13 known lycorine alkaloids and one lignan, were isolated. The structure and NMR assignments of this new alkaloid were determined by 1D and 2D NMR techniques. Littoraline showed inhibitory activity of HIV reverse transcriptase, and lycorine and haemanthamine showed potent in vitro cytotoxicity.

Diterpenes of Salvia prionitis

Abstract From the roots of Salvia prionitis Hance two new diterpenoids, salvinolone and salvinolactone, and two 4,5-seco-5,10-friedo-abietane diterpenoids, 4-hydroxy sapriparquinone and saprorthoquinone, have been isolated and their structures elucidated on the basis of their 1H and 13C NMR spectra.

Acylated C-21 steroidal bisdesmosidic glycosides from Caraluma umbellata

From the whole plant of Caraluma umbellata, three new C-21 steroidal glycosides, named as carumbellosides III-V, were isolated and their structures elucidated by extensive spectroscopic experiments, devoid of any derivatisation, as caralumagenin 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-digitalopyranoside-20-O-be ta- D-glucopyranoside, caralumagenin 3-O-beta-D-glucopyranosy(1-->4)- beta-D-digitalopyranoside-20-O-(2-O- benzoyl)-beta-D-glucopyranoside and caralumagenin 3-O-[6-O-benzoyl-beta-D-glucopyranosyl(1-->4)]-beta-D- digitalopyranoside-20-O-(2-O-benzoyl)-beta-D-glucopyranoside. The determination of the absolute configuration of the aglycone as (20 R), the conformations of the sugars and the unambiguous assignments of their NMR spectroscopic signals were achieved by a combination of 2D-NMR techniques. The isolates were devoid of significant cytotoxity in the UIC human cancer cell panel.

Two oxindole alkaloids from Gelsemium elegans.

Abstract Four new oxindole alkaloids, 20-hydroxydihydrorankinidine, N -desmethoxyhumantenine, 15-hydroxyhumantenine and gelsemoxonine have been isolated from Gelsemium elegans , and their structures assigned by spectral and X-ray crystallographic analyses.

Anacardoside from the seeds of Semecarpus anacardium

From the seeds of Semecarpus anacardium, a new phenolic glucoside, anacardoside, was isolated, and its structure and configuration were elucidated by a combination of NMR techniques as 1-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyloxy-3-hydro xy-5-methylbenzene.

Triterpene saponins from Aster yunnanensis

Four new triterpene saponins, asteryunnanosides A, B, C and D, have been isolated from Aster yunnanensis and their structures deduced as 2 alpha,3 beta,23-trihydroxyolean-12-en-28-oic acid-28-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 2 alpha,3 beta,23-trihydroxyolean-12-en-28-oic acid-28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, 2 alpha,3 beta-dihydroxyolean-12-en-28-oic acid-28-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside and 2 alpha,3 beta-dihydroxyolean-12-en-28-oic acid-28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, respectively, by means of spectral and chemical data.