Table 5

Identification of markers in the HPLC fingerprint of the formula by LC-MS analysis

APCI MS Data (Positive Ion)

Peak

Identification

Time (min)

M/QMIP^a

Other Peaks

MS² of M/QMIP

Plant Source^b

Content in formulation

(mg/kg)

1

Esculin

6.4

341 (M+H)⁺

179

179

FR

2

Chlorogenic acid

10.3

355 (M+H)⁺

163

163

AS

3

Aesculetin

12.0

179 (M+H)⁺

134, 123, 109

FR

310

4

Paeoniflorin

18.8

498 (M+H₂O)⁺

301, 179

301, 179

PL

5

prim-O-Glucosylcimifugin

23.8

469 (M+H)⁺

307

SD

6

Magnoflorine

32.2

342 (M)⁺

297, 265

CC, PA

7

Liquiritin

35.9

419 (M+H)⁺

307, 257

GU

8

5-O-Methylvisamminoside

49.9

453 (M+H)⁺

291

290

SD

9

Hesperidin

52.0

610 (M)⁺

465, 449, 303

463

CR

1460

10

Columbamine

60.2

338 (M)⁺

323, 294

CC

11

Jatrorrhizine

61.3

338 (M)⁺

323, 294

CC

12

Epiberberine

61.3

336 (M)⁺

CC

13

Coptisine

61.4

320 (M)⁺

304, 292

CC

14

Palmatine

66.5

352 (M)⁺

337, 308

CC, PA

420

15

Berberine

67.3

336 (M)⁺

321, 292

CC, PA

1620

16

Glycyrrhizic acid

76.2

823 (M+H)⁺

647, 471, 453, 406

GU

780

17

Schisandrin

81.8

433 (M+H)⁺

415

SC

140

18

Honokiol

93.3

266 (M)⁺

263

MO

63

19

Magnolol

98.6

266 (M)⁺

261

MO

93

20

Schisandrin A

107.7

417 (M+H)⁺

402, 347, 316

SC

Note: Peak number refers to the chromatographic fingerprint of the clinical preparation (Figure 4). Peaks 6, 10, 12, and13 were identified by LC-MS/MS2 analysis based on the literature values [17,18] and other peaks were identified by comparison of authentic chemicals. Jatrorrhizine and epiberberine (peaks 11, 12) were co-eluted with the same retention times.

^a Molecular or quasi-molecular ion peak; ^b FR: Fraxinus rhynchophylla; AS: Artemisia scoparia; PL: Paeonia lactiflora; SD: Saposhinikovia divaricata; GU: Glycyrrhiza uralensis; CR: Citrus reticulata; CC: Coptis chinensis; PA: Phellodendron amurense; SC: Schisandra chinensis; MO: Magnolia officinalis.

Ip et al. Chinese Medicine 2010 5:8   doi:10.1186/1749-8546-5-8