Clausena excavata Burm.f.

Last updated: 13 April 2016

Scientific Name

Clausena excavata Burm.f.


Amyris glaveolens Buch.-Ham. ex Steud., Amyris punctata Roxb. ex Colebr., Amyris punctata Roxb., Amyris sumatrana Roxb., Clausena excavate var. lunulata (Hayata) Yu. Tanaka, Clausena excavate var. villosa Hook.f., Clausena javensis Raeusch. ex DC., Clausena javensis J.F.Gmel., Clausena lunulata Hayata, Clausena moningerae Merr. Clausena punctata (Roxb.) Wight & Arn. ex Steud., Clausena punctata (Roxb.) Wight & Arn., Clausena sumatrana (Roxb.) Wight & Arn. ex Steud., Clausena tetramera Hayata, Cookia anisodora Blanco, Cookia anisum-olens Blanco, Cookia graveolens Wight & Arn., Cookia punctata Retz., Gallesioa graveolens M.Roem., Lawsonia falcate Lour., Murraya burmanni Spreng. [Unresolved]. [1]

Vernacular Name

Malaysia Chama, chamar, chemama, chemamah, cherek, cherek hitam, kematu, kemantu hitam, pokok kemantu, secherek, semeru, semura, semuru, semutuh [2]
English Hollowed clausena, pink lime-berry [2]
China Shan huang pi [2]
India Agni jala, bengjari, jangli bursunga, narasingha, opinjala, ote armu, somokhe, somsong, thaung-kuk, thengchauk, theng-sah-sauh-araung, thogkuk, ugani jard [2]
Indonesia Bajetah, temung, tikusan [2]
Thailand Huat mon, khee phueng, phia faan [2]
Laos Khong touang, kok sa mat, tcho kou nhia [2]
Philippines Buringit [2]
Cambodia Cantrouk san hoeut, sanitok damrey [2]
Vietnam Ch[uf]m h[oo]i, d[aa]m h[oo]i, h[oof]ng b[if] d[aj]i [2].

Geographical Distributions

Clausena excavata is a wild shrub which grows up to 1.5m high and is extensively distributed in Southeast Asia.  It is found in India (from the Coromandel and northern districts to Bhutan), Burma, Thailand, southern China, Vietnam, Laos, Cambodia, the Malay Peninsula, Sumatra, Java, Borneo, Philippines and New Guinea. [3][4]

Botanical Description

C. excavata is a tree or shrub in a family of Rutaceae. [3] This plant is hairy, strong smelled,  2-4(-5) m tall, stem up to 20 cm in diameter, and branching profusely. [4]

The leaves are odd-pinnate, rachis 15—50 cm long, leaflets alternate 15—31, ovate to ovate-lanceolate, 2—20 cm x 1—7 cm, base very oblique, apex long or short acuminate, margin entire or slightly dentate, when adult glabrescent above, thinly hairy beneath, and not winged. [3][4]

The inflorescences terminal or axillary, paniculate or laxly racemose, flowers often in cymose clusters, flower buds small, subglobose or short-oval or oblong, never long-cylindric. [3]

The flowers are small with 4-5 lobed calyx. The sepals fused into a cup below. The petals free, 4 or 5 imbricate in the bud, usually elliptical; stamens 10, in 2 whorls, the outer row opposite, the sepals usually longer, filaments more or less dilated or flattened below, often geniculate where the filiform apical portion joins the flattened and expanded basal portion, anthers ovate or elliptical, rarely short and subglobose. The gynophore well developed, usually a perfectly glabrous hourglass-shaped column supporting a strong histure ovary, resting on an annular nectary below and supporting (sometimes clasping). The base of the ovary above; ovary with 2-5 locules, often pubescent or glandular, ovules 2 in each locule (rarely 1). The style deciduous, often shorter than the ovary or equaling it in length (rarely longer), thick, sometimes merging gradually into the ovary, often sharply delimited and narrowed where it joins the ovary. The stigma is inconspicuous, sometimes subcapitate after the style shrivels. [3]

The berry broadly oblong, 1-2 cm long, reddish pink, with 2-5 segments, sometimes only 1 seed maturing and all flower parts are usually showing many (not all) cells strongly impregnated with tannin residues. [3][4]


No documentation.

Chemical Constituent

The acetone extract of the root bark of C. excavata contained carbazole alkaloids; clausine-M, -N, -O, -P, -Q, -R, -S, -U, -V and clausenatine-A, 2-hydroxy-3-formyl-7-methoxycarbazole, glycozolidal, heptaphylline, murrayafoline-A, 3-methylcarbazole, girinimbine, mukonal, mukonidine, mukonine, methyl carbazole-3-carboxylate, murrayanine, 3-formylcarbazole, clausine-C, -E, -F, -K, -T, -W, furoclausine-A, -B, clausevatine-D, -E, -F, -G, clausamine-A, carbazomarine-A and 2,7-dihydroxy-3-formyl-1-(3′-methyl-2′-butenyl) carbazole; the coumarins; claucavatin-A, claucavatin-B, kinocoumarin, clausenidin, clausarin, nordentatin, xanthoxyletin, xanthyletin, osthol, and cedrelopsin; and flavonoids, isoliquiritigenin and 4′,7-dihydroxyflavanone. [5][6]

The stem bark of C. excavata extract has been reported to contain carbazole alkaloids; lansine, heptaphylline, heptazoline, methyl carbazole-3-carboxylate, murrayanine (2-hydroxy-3-methylcarbazole, clausine-D; a coumarin, scopoletin; phenols, methyl p-hydroxycinnamate and syringaldehyde; tetranortriterpenoids, zapoterin and O-methylclausenolide and a carbazoquinone, clausenaquinone-A. [7][8]

The rhizomes and roots of C. excavata extract has been reported to contain carbazole derivative compounds (e.g. O-methylmukonal, 3-formyl-2,7-dimethoxycarbazole, and clauszoline J) and (e.g. pyranocoumarin, and clausenidin), respectively. [9]

The methanol extract of the stem bark of C. excavata contained clausines A, C, G and J which were identified as 3-formyl-2-hydroxy-8-methoxycarbazole 3-carbomethoxy-7-methoxycarbazole, 3-carbomethoxy-l-hydroxy-6-methoxycarbazole and 3-formyi-1, 7-dihydroxy-6-methoxycarbazole, respectively. [10]

The extract of stem bark and root bark of Clausena excavata has been reported to contain a binary carbazole alkaloid (e.g. clausenamine) and carbazole-pyranocoumarin dimer (e.g. carbazomarin-A), respectively. [11]

Clausine-L, a carbazole alkaloid and 11 known compounds, safrole, glutinol, 132-hydroxy( 132-R)-pheophytin-a, methyl pheophobide-a, scopoletin, steroidal glycoside [b-sitosteryl glucoside + stigmasteryl glucoside], 2-methoxy-4-(2-propenyl)phenyl-/3-D-glucoside, 2,6-dimethoxy-4-(2-propenyl)phenyl-b-D-glucoside, p-hydroxybenzoic acid, rutin, nicotiflorin, clauslactones-N-Q, and excavatins A-M were isolated from the leaves of C. excavata. [12][13][14]

Crude choloform extract of C. excavata rhizomes has been reported to contain coumarins (e.g. dentatin, nor-dentatin, clausenidin, and xanthoxyletin) and carbazole derivatives (e.g. 3-formylcarbazole, mukonal, 3-methoxycarbonylcarbazole, murrayanine, 2-hydroxy-3-formyl-7-methoxycarbazole, and clauszoline J). [15]

Plant Part Used

Stems, woods, and leaves. [12][16]

Traditional Use

In China, Indo-China, Thailand, Peninsular Malaysia and Java, the juice from the leaves is taken for intestinal worms or cough, and, sometimes together with Curcuma longa L., for fever, malaria or colds. The decoction of the leaves also has been used as a postpartum remedy; pounded leaves applied to the head for headache; leaflets ground with dry ginger and black peppers and the mixture taken in acute dyspepsia; leaf paste applied to the forehead for treatment of fever and headache; leaves juice rubbed on muscular pain. [2][4]

A decoction of the roots, flowers or leaves is taken for bowel complaints, such as colic, dyspepsia, stomach troubles, and stomach-ache. The pounded root or leaves are used as a poultice on sores, including ulceration of the nose, swellings, cut or sometimes for yaws. Ulcerations of the nose may also be treated by fumigation using burning leaves and bark. A decoction of the leaves is taken after childbirth. [2][4]

In Peninsular Malaysia the plant is also credited with magic virtues. In China, it is considered a bitter, tonic, astringent and emmenagogue. A poultice of the leaves is applied to treat paralysis. In Burma (Myanmar) the leaves are taken for stomach troubles. In Java the timber is used for handles of axes; it is white and has a fine structure. The leaves are insecticidal. [4]

Preclinical Data


Antiplatelet and vascular activity

The compounds isolated from C. excavata produced significant inhibition of rabbit platelet aggregation induced by arachidonic acid (100 µM), collagen (10 µg/mL) and platelet activation factor (2 ng/mL) and inhibited vasocontraction. Clausine E produced 58.3% and 89.3% inhibition of rat aorta phasic and tonic contraction induced by NE (3 µM), together with 87.0% inhibition of tonic contraction induced by K+ (80 mM) plus Ca2+ (1.9 mM).  Only one promotive constituent, O-methylclausenolide, was isolated, however the crude MeOH extract, partitioned layers and chromatographic fractions displayed both inhibitive and promotive effects on platelet aggregation. The simultaneous presence of both promotive and inhibitive constituents provided an explanation for the philosophy of use of C. excavata in Chinese medicine whereby promotive or inhibitive effects can be produced during therapy depending on the dose used and the variation in content. [7]

The clausenaquinone-A (10 µg/mL) which was isolated from the stem bark of C. excavata completely inhibited (100 ±0.8%) rabbit platelet aggregation induced by arachidonic acid (100 µM) and was cytotoxic to HCT-8, RPMI-7951 and TE671 tumour cells with IC50 values of 0.92, 0.22 and 3.82 I. µg/mL, respectively. [8]

The safrole (20 µg/mL) which was isolated from the leaves of C. excavata produced 70% inhibition of rabbit platelet aggregation which was induced by arachidonic acid (100 µM).  At a higher concentration, safrole (50 µg/mL) produced 48% inhibition of collagen (10 µg/mL)-induced platelet aggregation. [12]

The clausine-D that was isolated from C. excavata exhibited an antiplatelet effect which was mediated by inhibition of thromboxane A2formation. The aggregation and release reaction of washed rabbit platelets induced by arachidonic acid (100 µM) and collagen were inhibited by clausine-D in a concentration-dependent manner with IC50 values of 9.0 ± 1.1 and 58.9 ± 0.9 µM, respectively. Complete inhibition of arachidonate-induced platelet aggregation and ATP release reaction was elicited by 15 µM clausine-D.  A higher concentration of clausine-D (150 µM) was required to produce almost complete inhibition of collagen-induced platelet aggregation.  Even at this high concentration (150 µM), clausine-D only minimally inhibited aggregation induced by U46619 (1 µM), PAF (2 ng/mL) and thrombin (0.1 U/mL) in rabbit platelets.  The clausine-D (3-30 µM) also produced a concentration-dependent suppression of arachidonic acid-induced formation of thromboxane B2, a stable metabolite of thromboxane A2.  The thromboxane Bformation induced by collagen (10 µg/mL), PAF (2 ng/ml), and thrombin (0.1 U/ml) were markedly inhibited by clausine-D (30 µM).  Arachidonate-induced formation of prostaglandin D2 was inhibited by clausine-D (30 µM). [17]

The effect was similar to that produced by indomethacin (1 µM), a cycloxygenase inhibitor, while a thromboxane synthase inhibitor, imidazole (1 mM), decreased arachidonate-induced formation of thromboxane B2 but produced marked potentiation of arachidonate-induced formation of prostaglandin D2.  Many inducers of platelet aggregation cause breakdown of phosphoinositides.  Clausine-D (30 µM) abolished arachidonate (100 µM)-induced generation of inositol monophosphate.  However, the generation of inositol monophosphate by collagen (10 µg/mL), U46619 (1 µM), PAF (2 ng/mL) and thrombin (0.1 U/mL), agonists which were known to activate platelets, was unaffected by clausine-D.  The increase in intracellular calcium concentration in platelets that was inducible by both arachidonic acid (100 µM) and collagen (10 µg/mL) was inhibited by clausine-D (30 µM).  Epinephrine (5 µM) and ADP (3 µM) caused biphasic aggregation in human citrated platelet-rich plasma.  The secondary phase, although not the primary phase, of epinephrine- and ADP-induced aggregation in human platelet-rich plasma was inhibited by clausine-D in a concentration-dependent manner. The secondary aggregation was known to depend on the generation of thromboxane A2 and on the release of ADP, and to be inhibited by cyclooxygenase inhibitors.  The antiplatelet effect of clausine-D closely resemble that of indomethacin but was different from that of the thromboxane synthase inhibitor, imidazole. [17]

The clausine Z which was isolated from the stems and leaves of C. excavata showed inhibitory activity against cyclin-dependent kinase 5 and protected cerebellar granule neurons in vitro[18] 

Immunomodulating activity

The aqueous extract of the wood of C. excavata and a Thai folklore preparation of the plant showed potential in vivo immunomodulating activities in Balb/C mice. Prior to treatment with the extracts, mice were injected with sheep erythrocyte suspension (1×10cells/0.2 mL buffered saline, i.p.).  The mice were then fed (2.5 g/mL dose for each extract) or intraperitoneally (i.p.) injected (0.4 g/mL dose for each extract) with the extracts daily for 5 days after which all mice were again immunized with sheep erythrocyte suspension.  The serum haemagglutinating antibody titers were determined at days 0, 7, 14, 21, 28 and 35 for evaluation of humoral mediated immunity.  The cimetidine (10 mg/mL) was used as the positive control.  Cell mediated immunity to determine delayed type hypersensitivity was assessed by the footpad swelling test.  Mice were first immunized with an i.p. injection of sheep erythrocyte suspension (1×108 cells/0.2 mL buffered saline) and then treated with the extracts (0.4 g/mL dose for each extract) by i.p. or oral administrations or with dexamethasone (0.5 mg/mL, i.p.) or indomethacin (10 mg/mL, i.p.) which were the positive controls. [16]

Seven days later, the left hind paw was challenged with sheep erythrocyte suspension (1×108 cells), while the right hind paw served as the control.  Both the aqueous extract and the folklore preparation when administered produced the same maximum antibody production of 1/800 on day 21, which was twice that of the control.  The cimetidine as the positive control produced a maximum titer of 1/1600 on day 21.  With oral administration, both extracts and cimetidine produced the maximum antibody titer of 1/800 on day 7 which was twice that of the control.  The oral response occurred earlier than the response elicited by intraperitoneal injections of the extracts.  The antibody titers elicited by the aqueous extract, i.p., was not retained while that produced by the folklore preparation was retained for 1 week.  The aqueous extract was more effective than the folklore extract for reduction of cell mediated immunity. The footpad swelling was reduced by the aqueous extract to a similar extent as the reduction caused by indomethacin, and about 95% of that due to dexamethasone. [16]

The effects of fractions from the hot aqueous extract, acetone extract and the folklore preparation of C. excavata were studied on mouse splenocyte proliferation to demonstrate the plant’s immunomodulatory activity. The fractions eluted from the hot aqueous extract and acetone extract significantly increased mouse splenocyte proliferation although not in a dose-dependent manner, while fractions obtained from the folklore preparation were less active.  In vitro, the crude extracts obtained by aqueous and acetone hot extraction produced significant phagocytosis and proliferative activity in the mouse immune system. [19]

The aqueous extract, acetone extract and the Thai folklore extract of C. excavata showed immunomodulatory activities on the mouse immune system. The extracts showed effective phagocytic activation with the aqueous extract eliciting the maximum response on both the respiratory burst and lysosomal enzyme activity while the responses elicited by the acetone and Thai folklore extracts were smaller.  The splenocyte proliferation assay was carried out in the absence and presence of mitogens (lipopolysaccharide, LPS or pokeweed mitogen).  In this assay, the Thai folklore extract with LPS elicited the maximum response, higher than that obtained with pokeweed mitogen.  This suggests that the Thai folklore extract was specific for B cell proliferation through the T cell independent pathway, similar to LPS. [20]

Anticancer activity

The clausemine-A which was isolated from the stem and root bark of C. excavata showed moderate activity in a disease-oriented antitumor screen in vitro which determined a compound’s effectiveness on the growth parameters of approximately 60 human tumor cell lines. The clausemine-A exhibited fairly good activity against leukemia, nonsmall cell lung, colon, CNS, melanoma, ovarian, renal, prostate, and breast cancer. [21]

Antinociceptive activity

The ethanolic extract of C. excavata leaves (125.25 and 500 mg/kg body weight, p.o.) produced significant antinociceptive activity in the acetic acid-induced writhing test in mice. [22]

Antibacterial activity

The nordentatin isolated from the root bark exhibited strong antibacterial activity. [6] The coumarins, dentatin, nordentatin, clausenidin and the carbazole derivatives, 3-formylcarbazole, mukonal, 3-methoxycarbonylcarbazole, 2-hydroxy-3-formyl-7-methoxycarbazole and clauszoline J exhibited antimycobacterial activity with minimum inhibitory concentrations (MIC) of 50, 100, 200, 100, 200, 50, 100 and 100 µg/mL, respectively. 3-Formylcarbazole, mukonal, 3-methoxycarbonylcarbazole and 2-hydroxy-3-formyl-7-methoxycarbazole also showed antifungal activity with IC50 values of 13.6, 29.3, 9.5 and 2.8 µg/mL, respectively.  None of the compounds was cytotoxic to KB and BC-1 cell lines. [15]

Anti-HIV activity

The O-Methylmukonal, 3-formyl-2,7-dimethoxycarbazole and clauszoline J and clausenidin isolated from the rhizomes and roots of C. excavata exhibited anti-HIV-1 activity in a syncytial assay with EC50 values of 12, 29.1, 34.2 and 5.3 µM, respectively. All four compounds were non cytotoxic to KB and BC-1 cancer cell lines. [9]

Clausenolide-1-ethyl ether, which was obtained from the crude ethanol extract of the rhizomes and the root exhibited HIV-1 inhibitory activity. The dentatin and nordentatin which were obtained from the crude chloroform extract of the rhizomes induced toxicity to cells used in a syncytium assay for anti-HIV-1 activity. [23]


The Thai folklore extract of the wood of C. excavata had an i.p. LD50 value in rats of 1.6 g/kg body weight while the oral LD50 value in rats was more than 10 g/kg body weight. [16]

The clausenolide-1-ethyl ether, dentatin and nordentatin were not cytotoxic against KB and BC-1 cell lines (IC50 value > 20 µg/mL). [23]

Clinical Data

Clinical findings

Anticancer activity

The folklore preparation of C. excavata wood produced an increase of CD4/CD8 ratio in advanced cancer patients who took the crude extract orally. [19]


No documentation.

Side effects

No documentation.

Pregnancy/Breast Feeding

No documentation.

Age limitation

No documentation.

Adverse reaction

No documentation.

Interaction & Depletion

No documentation.

Interaction with drug

No documentation.

Interaction with other Herbs

No documentation.


No documentation.

Case Report

No documentation.


No documentation.

Poisonous Management

No documentation.

Line drawing

No documentation.


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