Pharmacognosy Magazine

ORIGINAL ARTICLE
Year
: 2019  |  Volume : 15  |  Issue : 65  |  Page : 736--739

Chemical composition from the leaves of Lindera fragrans Oliv.


He-Zhong Jiang1, Tian Gan1, Ya-Nan Li1, Chun-Yan Du1, Jun-Long Li2, Jun-Ting Fan3, Rui Tan1,  
1 School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, China
2 Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu, China
3 Department of Pharmaceutical Analysis, School of Pharmacy, Nanjing Medical University, Nanjing, China

Correspondence Address:
He-Zhong Jiang
School of Life Science and Engineering, Southwest Jiaotong University, Chengdu
China
Rui Tan
School of Life Science and Engineering, Southwest Jiaotong University, Chengdu
China

Abstract

Background: One hundred known species belong to the genus Lindera (Lauraceae) and rich in chemical structure types. The branch leaves of Lindera fragrans Oliv. show the special curative effect of treating gastroenteritis and gastric ulcer. There are not comparatively detailed reports carried on studying the chemical composition and bioactivity of L.fragrans. Objective: This paper reports the chemical investigation and biological evaluation of the L.fragrans. Materials and Methods: The petroleum ether and ethyl acetate soluble part of L.fragrans was isolated using chromatographic methods, and the structures of these compounds were identified by comparison of their spectroscopic data with those reported in the literature. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method was used to determine the antitumor activity of the isolated compounds. Results: Twelve compounds were isolated from the leaves of L.fragrans and classified as six alkaloids (1–6), three flavonoids (7–9), two aromatics (10 and 11), and one anthraquinone (12). The study of antitumor activity showed that compounds 3–5 had weak antitumor activities with the half maximal inhibitory values ranging from 71.97 to 94.69 μM. Conclusion: All of these compounds were isolated from this plant for the first time and compounds 3–6, 8, and 9 were first reported from the genus Lindera. Compounds 3–5 exhibited weak antitumor activities. The chemical investigation of the leaves of Lindera fragrans resulted in the isolation of 12 compounds including six alkaloids (1–6), three flavonoids (7–9), two aromatics (10 and 11), one anthraquinone (12). The isolated compounds 3–9 were evaluated for their cytotoxicity against melanoma, glioma, and hepatoma cells by MTT method.



How to cite this article:
Jiang HZ, Gan T, Li YN, Du CY, Li JL, Fan JT, Tan R. Chemical composition from the leaves of Lindera fragrans Oliv. Phcog Mag 2019;15:736-739


How to cite this URL:
Jiang HZ, Gan T, Li YN, Du CY, Li JL, Fan JT, Tan R. Chemical composition from the leaves of Lindera fragrans Oliv. Phcog Mag [serial online] 2019 [cited 2020 Aug 5 ];15:736-739
Available from: http://www.phcog.com/text.asp?2019/15/65/736/267165


Full Text



SUMMARY

The chemical investigation of the leaves of Lindera fragrans Oliv. resulted in the isolation of 12 compoundsThe 12 compounds include six alkaloids (1–6), three flavonoids (7–9), two aromatics (10 and 11), and one anthraquinone (12)The isolated compounds 3–9 were evaluated for their antitumor activitiesThe chemotaxonomic significance of all the isolations was summarized.

[INLINE:1]

The chemical investigation of the leaves of Lindera fragrans resulted in the isolation of 12 compounds including six alkaloids (1–6), three flavonoids (7–9), two aromatics (10 and 11), one anthraquinone (12). The isolated compounds 3–9 were evaluated for their cytotoxicity against melanoma, glioma, and hepatoma cells by MTT method.

Abbreviations used: EtOAc: Ethyl acetate; n-BuOH: N-butyl alcohol; MCI: Middle chromatogram isolated; HPLC: High-performance liquid chromatography; MS: Mass spectrometer; NMR: Nuclear magnetic resonance; TLC: Thin-layer chromatography; MTT: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; IC50: Half maximal inhibitory; B16: Melanoma cells; C6: Glioma cells; HepG2: Hepatoma cells.

 Introduction



The genus Lindera (Lauraceae) widely distributes in tropics and subtropics. The wide geographical distribution makes Lindera plants rich in chemical structure types. At present, more than 300 chemical constituents have been found in the genus Lindera including sesquiterpenes, alkaloids, flavonoids, lignans, and butyrolactones. Among them, eucalyptus, urea alkanes, furan cyclosporine, and isoquinoline alkaloids (apophine alkaloids) are the characteristic chemical constituents of the genus Lindera.[1]Lindera fragrans Oliv. is mainly distributed in Hunan, Hubei, and Sichuan in China and its branch leaves are the main medicinal parts in treating gastroenteritis and gastric ulcer.[2] At present, no comparatively detailed research had addressed the chemical composition and bioactivity of L.fragrans. Previous phytochemical studies on Lindera nacusua (D. Don) Merr. by our group reported the isolation and identification of anthraquinones, gamma-butanolides, phenolic glycosides, phenolic acid amides, and cerebroside.[3]

 Materials and Methods



Plant material

The leaves of L. fragrans were collected from Jiange County, Sichuan Province, China, and identified by Prof. Liang-Ke Song (Southwest Jiaotong University). Voucher specimen (XYZ001) was deposited at the Laboratory of Traditional Chinese Medicinal Chemistry, Southwest Jiaotong University, China.

Extraction and isolation

The air-dried leaves of L.fragrans (2.9 kg), after comminution, extracted with 95% ethanol 3 times. After removal of solvent under reduced pressure, the extract (270 g) was suspended in water followed by successive partition with petroleum ether, ethyl acetate (EtOAc), and n-butanol, respectively.

Then, the petroleum ether soluble part (104.1 g) was subjected on silica gel column with a gradient solvent petroleum ether/acetone (100:1–1:1, v:v) to give 13 fractions (P1–P13). Fraction P7 (769 mg) was chromatographed over a Sephadex LH-20 column (CHCl3/MeOH, 1:1, v:v) to give compound 1 (2 mg). Fraction P9 (2949 mg) was separated on middle chromatogram isolated, which elution system was CH3 OH/acetone (1:0–0:1, v:v), to afford six fractions (P9-1–P9-6). Fraction P9-5 (113 mg) was further purified with a Sephadex LH-20 column (CHCl3/MeOH, 1:1, v:v) to yield compound 2 (5.6 mg). Silica gel column chromatography was used to further purify the EtOAc extract (61.5 g), which elution solvent was CH2 Cl2/CH3 OH (100:1–1:1, v:v) and 12 subfractions were obtained (E1–E12). Fraction E10 (10.2 g) was separated on RP-18 (MeOH/H2O, 30%–100%, v:v) to give 10 subfractions (E10-1–E10-10). Fraction E10-9 (408 mg) was further purified on Sephadex LH-20 (MeOH) to give compound 12 (5 mg); compound 7 (32 mg) was obtained from fraction E10-5 (507 mg) in the same way. Fraction 10-4 was loaded on silica gel column using CH2 Cl2-CH3 OH (30:1–1:1, v:v) as eluent and then produced six fractions (E10-4-1–E10-4-6). Compounds 11 (6 mg) and 10 (5 mg) were purified by semi-preparative high-performance liquid chromatography (HPLC) using 55% MeOH in H2O from E10-4-6 (213 mg). Compound 9 (10 mg) was isolated by Sephadex LH-20 (MeOH) from fraction E10-4-4 (123 mg). Fraction E10-6 (925 mg) was submitted to Sephadex LH-20 (MeOH) and semi-preparative HPLC to yield compounds 8 (48 mg), 6 (3.1 mg), and 4 (9 mg). Fraction E10-8 was subjected to Sephadex LH-20 (MeOH) to afford fractions E10-8-1–E10-8-4. Fraction E10-8-3 (167 mg) was further separated by Sephadex LH-20 (CHCl3/MeOH, 1:1, v:v) and semi-preparative HPLC to produce compounds 5 (3 mg) and 3 (4.6 mg).

Cytotoxicity bioassay

3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method, as previously described,[4] was used to determine the antitumor activity of the isolated compounds 3–9 against three cell lines: melanoma, glioma, and hepatoma cells (B16, C6, and HepG2 cells), respectively. These cells were provided by West China School of Pharmacy, Sichuan University; dimethyl methyl sulfate (DMSO) was purchased from Sigma-Aldrich, and Dulbecco's modified Eagle Medium was purchased from GIBCO BRL. Half maximal inhibitory (IC50) values were calculated by Reed and Muench's method.

 Results



The present study reports 12 known compounds, including six alkaloids (1–6), three flavones (7–9), two aromatics (10 and 11), and one anthraquinone (12). All of them were first isolated from this plant and compounds 3–6, 8, and 9 were first reported from the genus Lindera.

Twelve compounds [Figure 1] were identified as nordicentrine (1),[5] phanostenine (2),[6] cryptodorine (3),[7] neolitsine (4),[8] dehydroneolitsine (5),[9] anolobin (6),[10] kaempferol-3-O-α-L-rhamnoside (7),[11] kaempferol-3,7-O-α-L-dirhamnoside (8),[12] kaempferol-3-O-β-D-xylopyranosyl-(1 → 2)-α-L -rhamnopyranoside (9),[13]p-methoxyphenylacetic acid (10),[14] 4-methoxycinnamic acid (11),[15] demethylmacrosporine I (12),[16] by analysis of mass spectrometry and nuclear magnetic resonance (NMR) data and comparison with those in the literature.{Figure 1}

Nordicentrine (1)

C19H19 NO4, colorless oil; HRESI-MS(*): m/z = 326.1314 [M*H]*;1 H NMR (600 MHz, CDCl3): δ= 7.61 (1H, s, H-11), 6.73 (1H, s, H-8), 6.47 (1H, s, H-3), 6.04 (1H, br, -OCH2O-), 5.89 (1H, br, -OCH2O-), 3.87 (6H, s, 9, 10-OCH3), 3.79 (1H, m, H-6a), 3.44 (1H, br, H-5), 2.57 (5H, m, H-4, 5, 7), 1.98 (1H, s, N-H).

Phanostenine (2)

C19H19 NO4, colorless oil; HRESI-MS(*): m/z = 326.1386 [M*H]*;1 H NMR (600 MHz, CDCl3): δ

= 7.60 (1H, s, H-11), 6.79 (1H, s, H-8), 6.50 (1H, s, H-3), 6.07 (1H, br, -OCH2O-), 5.92 (1H, br, -OCH2O-), 3.98 (3H, s, 9-OCH3), 3.71 (1H, m, H-6a), 3.20 (2H, m, H-7), 3.06 (2H, m, H-4), 2.66 (2H, m, H-5), 2.61 (3H, s, N-CH3);13 C NMR (150 MHz, CDCl3): δ= 147.0 (C-10), 145.6 (C-9), 145.3 (C-2), 141.9 (C-1), 130.2 (C-7a), 129.4 (C-3a), 126.5 (C-3b), 122.8 (C-11a), 116.8 (C-11b), 114.4 (C-11), 110.0 (C-8), 106.7 (C-3), 100.8 (-OCH2O-), 62.2 (C-6a), 56.2 (9-OCH3), 53.1(C-5), 43.7 (N-CH3), 33.3 (C-7), 22.7 (C-4).

Cryptodorine (3)

C18H15 NO4, colorless oil; HRESI-MS (*): m/z = 310.1012[M*H]*;1 H NMR (600 MHz, CDCl3): δ = 7.58 (1H, s, H-11), 6.77 (1H, s, H-8), 6.59 (1H, s, H-3), 6.13, 5.97 (2H, d, J = 1.37 Hz, -OCH2O-), 6.00, 5.98 (2H, d, J = 1.40 Hz, -OCH2O-), 3.47 (1H, s, H-6a), 2.08 (1H, s, N-H)

Neolitsine (4)

C19H17 NO4, colorless crystals; HRESI-MS (*): m/z = 324.1223 [M*H]*;1 H NMR (600 MHz, CDCl3): δ = 7.56 (1H, s, H-11), 6.70 (1H, s, H-8), 6.47 (1H, s, H-3), 6.01-5.93 (2H, d, J = 1.32 Hz, -OCH2O-), 5.91-5.88 (2H, d, J = 1.32 Hz, -OCH2O-), 3.13 (1H, m, H-6a), 3.1 (2H, m, H-7), 3.0 (2H, m, H-4), 2.6 (2H, m, H-5), 2.5 (3H, s, N-CH3);13 C NMR (150 MHz, CDCl3): δ = 146.8 (C-2), 146.7 (C-9), 146.6 (C-7), 142.0 (C-1), 129.6 (C-7a), 126.4 (C-3a), 126.1 (C-11c), 124.5 (C-11a), 116.7 (C-11b), 108.7 (C-11), 107.5 (C-8), 106.9 (C-3), 101.0 (-OCH2O-), 100.7 (-OCH2O-), 62.2 (C-3a), 53.5 (C-5), 43.7 (N-CH3), 34.5 (C-7), 27.3 (C-4).

Dehydroneolitsine (5)

C19H15 NO4, yellow powder; HRESI-MS(*): m/z = 344.1086[M*Na]*;1 H NMR (600 MHz, CDCl3): δ x= 8.38 (1H, s, H-11), 7.59 (1H, s, H-8), 6.73 (1H, s, H-3), 6.51 (1H, s, H-7), 6.05, 5.94 (2H, d, J = 1.39 Hz, -OCH2O-), 5.96, 5.92 (2H, d, J = 1.91 Hz, -OCH2O-), 2.61 (3H, s, N-CH3).

Anolobin (6)

C17H15 NO3, colorless oil; HRESI-MS(*): m/z = 282.1134[M*H]*;1 H NMR (600 MHz, CDCl3): δ = 8.21 (1H, br, H-11), 8.05 (1H, brd, J = 7.97 Hz, H-10), 7.27 (1H, d, J = 2.07 Hz, H-8), 6.54 (1H, s, H-3), 6.06, 5.93 (2H, d, J = 1.32 Hz, -OCH2O-), 3.13 (1H, dd, J = 14.01, 4.59 Hz, H-6a), 2.77 (1H, s, N-H).

Kaempferol-3-O-α-L-rhamnoside (7)

C21H20O10, yellow powder; HRESI-MS(*):m/z = 433.1130[M*H]*; m/z = 455.0946[M*Na]*;1 H NMR (600 MHz, CD3 OD): δ = 7.76–7.74 (2H, d, J = 8.8 Hz, H-2', 6'), 6.91-6.93 (2H, d, J = 8.8 Hz, H-3', 5'), 6.33 (1H, d, J = 2.1 Hz, H-8), 6.18 (1H, d, J = 2.1 Hz, H-6), 5.37 (1H, d, J = 1.7 Hz, H-1''), 4.23 (1H, dd, J = 1.7 Hz, 3.3 Hz, H-2''), 3.70-3.72 (1H, m, H-3''), 3.32-3.33 (1H, m, H-4''), 3.30-3.31 (1H, m, H-5''), 0.92 (3H, d, J = 5.7 Hz, H-CH3);13 C NMR (150 MHz, CD3 OD): δ = 178.2 (C-4), 164.6 (C-7), 161.6 (C-5), 160.2 (C-4'), 157.9 (C-9), 157.2 (C-2), 134.8 (C-3), 130.6 (C-2', 6'), 121.3 (C-1'), 115.1 (C-3', 5'), 104.5 (C-10), 102.1 (C-1'), 98.5(C-6), 93.4 (C-8), 71.8 (C-3''), 70.75 (C-5''), 70.69 (C-4''), 70.58 (C-2''), 16.3 (C-6'').

Kaempferol-3, 7-O-α-L-dirhamnoside (8)

C27H30O14, yellow crystals; HRESI-MS(*): m/z = 601.1313[M*Na]*, 1 H NMR (600 MHz, CD3 OD): δ = 7.77-7.74 (2H, d, J = 8.88 Hz, H-2H, d, RESI-MS(*): e (8) 160J = 8.88 Hz, H-3H, d, RESI-MS(*): e (8J = 2.09 Hz, H-8), 6.42 (1H, d, J = 2.09 Hz, H-6), 5.53 (1H, d, J = 1.78 Hz, H-1), 5.53 (1H, d,): J = 2.01 Hz, H-1), 5.53 (1H, d,):J = 6.16 Hz, -CH3), 0.90 (3H, d, J = 5.70 Hz, -CH3);13 C NMR (150 MHz, CD3 OD): δ = 182.5 (C-4), 166.2 (C-7), 165.7 (C-5), 164.5 (C-4'), 162.5 (C-9), 160.7 (C-2), 139.1 (C-3), 134.7 (C-2', 6'), 125.0 (C-1'), 119.2 (C-3', 5'), 110.2 (C-10), 106.2 (C-1''), 103.2 (C-6), 102.2 (C-1'''), 98.2 (C-8), 20.8 (C-6'''), 20.4 (C-6'').

Kaempferol-3-O-β-D-xylopyranosyl-(1→2)-α-L- rhamnopyranoside (9)

C26H28O14, yellow powder; HRESI-MS(*): m/z = 587.1370[M*Na]*, 1 H NMR (600 MHz, CD3 OD) δ = 7.91-7.90 (2H, d, J = 8.08 Hz, H-2H, d, -MS(*): osyl-(1 → 2)-α-LJ = 8.08 Hz, H-3H, d, -MS(*): osybr, H-8), 6.42 (1H, br, H-6), 5.53 (1H, br, H-1''), 4.41 (1H, d, J = 2.17 Hz, H-13H, d, -MS(*): osybJ = 6.13 Hz, -CH3);13 C NMR (150 MHz, CD3 OD): δ = 178.4 (C-4), 164.9 (C-7), 161.7 (C-5), 160.2 (C-4'), 157.5 (C-9), 157.1 (C-2), 133.4 (C-3), 130.6 (C-2', 6'), 121.3 (C-1'), 115.3 (C-3', 5'), 106.4 (C-1'''), 104.2 (C-10), 99.9 (C-1''), 98.6 (C-6), 93.6 (C-8), 16.6 (C-6'').

p-Methoxyphenylacetic acid (10)

C9H10O3, yellow oil; HRESI-MS(*): m/z: = 189.0634 [M*Na]*;1 H NMR (600 MHz, CD3 OD): δ = 6.78 (2H, d, J = 8.7 Hz, H-2, CDMS(*):), 161.7 J = 8.7 Hz, H-3, CDMS(*):)(H, m, H-2), 3.82 (H, m, H-2), 3.71 (3H, s, -OCH3);13 C NMR (150 MHz, CD3 OD) δ = 173.8 (C-1), 155.39 (C-4'), 129.69 (C-2', C-6'), 128.75 (C-1'), 114.38 (C-3', C-5'), 51.16 (4'-OCH3), 44.55 (C-2).

4-Methoxycinnamic acid (11)

C10H10O3, yellow crystals; HRESI-MS(*): m/z = 282.1134[M*Na]*;1 H NMR (600 MHz, CD3 OD): δ = 7.58–7.56 (1H, d, J = 16.0 Hz, H-7), 7.42–7.41 (2H, d, J = 8.6 Hz, H-2, 6), 6.77-6.75 (2H, d, J = 8.6 Hz, H-3, 5), 6.30-6.28 (1H, d, J = 16.0 Hz, H-8), 3.72 (3H, s, OCH3);13 C NMR (150 MHz, CD3 OD): δ = 169.9 (C-9), 161.4 (C-4), 146.7 (C-7), 131.3 (C-2, 6), 127.2 (C-1), 116.9 (C-3, 5), 115.0 (C-8), 52.1 (OCH3).

Demethylmacrosporine I (12)

C15H10O5, orange crystals; HRESI-MS(*): m/z = 293.0423[M*H]*;1 H NMR (600 MHz, CDCl3): δ = 7.52 (1H, s, H-5), 7.16 (1H, br d, J = 2.3 Hz, H-4), 7.01 (1H, s, H-8), 6.56 (1H, br d, J = 2.4 Hz, H-2), 2.37 (3H, s, H-15);13 C NMR (150 MHz, DMSO-d 6): δ = 190.1 (C-10), 181.7 (C-13), 166.0 (C-1), 164.9 (C-3), 161.8 (C-6), 148.6 (C-7), 135.4 (C-12), 133.1 (C-9), 124.5 (C-8), 120.9 (C-5), 113.7 (C-14), 109.3 (C-11), 109.2 (C-4), 108.3 (C-2), 22.0 (C-15).

The isolated compounds 3–9 were evaluated for their cytotoxicity against B16, C6, and HepG2 cells by MTS method. As a result, compounds 3–5 showed weak inhibitory effect against B16 cell line with IC50 values of 71.97, 73.63, and 94.69 μM, respectively, while the other four compounds exhibited unobvious cytotoxic activities with IC50 values greater than 100 μM.

 Discussion



This is the first report on the phytochemical investigation of L. fragrans. In the present paper, the compounds 1–6 got from L. fragrans were classified as apophine alkaloids that confirmed the chemical composition similarity in homologous plants. No related reports of the genus Lindera had mentioned the compounds 3–6, which can be used to distinguish L. fragrans with other plantsof Lindera. Compounds 7–9 were classified as flavonoids, which are the other major constituents in Lindera.

 Conclusion



Twelve known compounds were isolated from the leavesof L. fragrans for the first time, and compounds 3–6, 8, and 9 were first reported from the genus Lindera. Compounds 3–5 exhibited weak antitumor activities with the IC50 values ranging from 71.97 to 94.69 μM.

Acknowledgements

We are grateful to the members of the analytical group of Chengdu Institute of Biology, Chinese Academy of Sciences, for the spectral measurements.

Financial support and sponsorship

This work was co-supported by the Fund of Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of Antibiotics, Chengdu University (ARRLKF17-10), the Fund of Science and Technology Agency of Chengdu (2019-YF09-00049SN, 2015-HM01-00311-SF), the Fundamental Research Funds for the Central Universities, the Administration of Traditional Chinese Medicine of Sichuan (2017PC004), the 13th Personalized Experimental Project and the Student Research Training Program (SRTP, 2019156).

Conflicts of interest

There are no confilicts of interest.

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