Alpinia (PROSEA Medicinal plants)

Plant Resources of South-East Asia
Introduction

List of species

Alpinia Roxb.

Protologue: Asiat. Res. 11: 350 (1810).

Family: Zingiberaceae

Chromosome number: x= 24; A. galanga: 2n= 48, A. malaccensis: 2n= 48; A. mutica: 2n= 48, A. zerumbet: 2n= 42

Major species

Alpinia galanga (L.) Willd.,
A. officinarum Hance,
A. zerumbet (Pers.) B.L. Burtt & R.M. Smith

Vernacular names

Papua New Guinea: esege (Sui, Northern Province), henigugau (Maiwara, Milne Bay), patu (Wapenamanda, Enga).

Origin and geographic distribution

Alpinia is a large, polymorphic genus, comprising over 250 species. It occurs throughout South and South-East Asia, from India to Japan, southward to New Guinea, the Solomon Islands, Fiji, Samoa and Australia.

Uses

The rhizome of medicinally used Alpinia is generally taken as a stomachic, for indigestion, stomach-ache and diarrhoea, and also as an emetic and as an expectorant. It is also externally applied for rheumatism, wounds, sores and ringworm. The leaves are used for the latter purpose as well, with the intention of drawing blood to the skin.

In Peninsular Malaysia A. conchigera is frequently used, often externally. A poultice of the boiled leaves, or of the leaves and rhizome together, is applied for rheumatism, and the same ingredients are also used for bathing. The pounded leaves are used as a poultice after confinement. The fruits are very pungent. On the eastern coast of Peninsular Malaysia juice of the rhizome is mixed with milk and drunk as a tonic. In Indo-China the rhizome is considered stimulating, bechic, diaphoretic, and to regulate menses. It is used in the treatment of bronchitis, jaundice, headache, vertigo or metritis. A poultice of the rhizome serves as an external treatment for fungal skin infection.

The rhizomes of A. galanga are official in several European pharmacopoeias and have a strong pungent taste. They are widely used in traditional medicine, in skin diseases, respiratory diseases, as a stomachic after childbirth, in indigestion, flatulence, colic, dysentery, cancers of mouth and stomach, for treatment of systemic infections and cholera, and as an expectorant. In India, Indo-China and China the rhizome is taken for dyspepsia, for convulsions as a carminative, and as an expectorant for bronchitis, externally it is applied for rheumatism. In Thailand the rhizome is used for a large array of ailments, for purifying blood, indigestion, contusions, diarrhoea, tetanus infection, chronic malaria, beriberi, yaws, stomach-ache, cholera, itching, ringworm, skin diseases, impetigo, urticaria, toothache, and as an antispasmodic, anthelminthic, carminative, antiflatulence and laxative. In the Philippines the rhizomes are considered carminative and stimulant, and a decoction of the leaves is used for antirheumatic and stimulant baths. The rhizomes of A. officinarum are more aromatic and pungent than those of A. galanga, and the local use of both species is more or less the same.

In the Philippines a decoction of the leaves of A. zerumbet is used as a bath against fevers. In China the seed is used to clear away cold, invigorate the spleen and warm the stomach. Components from the seed have shown anti-stomach-ulcer properties. The rhizome has antibacterial properties and stimulates digestion. It is indicated in the treatment of dyspepsia, flatulence, vomiting, gastralgia, colic, diarrhoea and malaria.

The rhizomes are used in Taiwan in the treatment of vomiting, dyspepsia and gastric ulcers. In China the plant is employed to treat stomach disorders, vomiting and dyspepsia. Its rhizome is traditionally used as a stomachic, carminative, astringent, tonic and sedative.

The slender A. aquatica (Retz.) Roscoe (synonyms Languas melanocarpa Burkill, Alpinia melanocarpa Ridley) is found on sandy localities near the sea in Peninsular Malaysia, and has stout, aromatic, perhaps even bitter rhizomes. It is not used widely for medicinal purposes, although a decoction of the plant is known to be taken during the first 3 days after confinement, and a decoction of the flowers is taken for cholera. A hot water fomentation of the leaves, or the heated leaves of the stout A. scabra (Blume) Baker (synonym Languas scabra Burkill), occurring in the hills of Peninsular Malaysia and Java, are applied to the abdomen for vertigo.

In China the rhizome of A. chinensis (Retz.) Roscoe (synonym Languas chinensis Retz.) is taken as a stomachic, for indigestion and to relieve stomach-ache, diarrhoea, rheumatism and pain in the joints, and has therefore been planted in gardens in Peninsular Malaysia by the Chinese. The rhizome is also taken for sunstroke, and activates slow blood circulation. In China and Indo-China the seed of A. katsumadai Hayata is used to strengthen the spleen, as a stomachic and to arrest vomiting, also for stomach problems such as dyspepsia, diarrhoea and alcoholic intoxication.

Many species of Alpinia, including A. bracteata Roxb., A. malaccensis, A. mutica, A. nigra Burrt and A. zerumbet, are cultivated as garden plants and as potplants for their attractive, often variegated leaves and striking inflorescences.

Production and international trade

Data on the production, consumption and trade of the rhizome of A. galanga and A. officinarum are scarce and unreliable because often no distinction is made between the 2 species. Production in South-East Asia is considerable as it is a common spice used daily by millions of people. No information is available on the production and trade of lesser-known Alpinia.

Properties

Alpinia is a genus in which many complex compounds are found in the aerial parts and in the rhizomes. Several species contain diarylheptanoids, which in structure resemble the curcuminoids (e.g. curcumin, from Curcuma) and which possess potent anti-inflammatory properties. Several tests with 3 such compounds, yakuchinone B, dimethyl-yakuchinone B and 1-(3,5-dimethoxy-4-hydroxyphenyl)- 7-phenylhept-1-en-3-one, were performed in vitro and in vivo, and the results suggest that their anti-inflammatory action is at least in part due to their suppressive effect on the surface expression of inducible adhesion molecules in endothelial cells, and subsequent leukocyte adhesion. In addition, the diarylheptanoids were found to be potent inhibitors of the prostaglandin biosynthesizing enzyme (PG synthetase) and arachidonate 5-lipoxygenase, an enzyme of the leukotriene biosynthesis. This was verified by testing their inhibitory effects of 5-lipoxygenase prepared from RBL-1 cells. A diarylheptanoid with a catechol group was the most active compound against 5-lipoxygenase. Besides the presence of diaryheptanoids (e.g. 1-(4-hydroxyphenyl)-7-phenylheptane-3,5-diol), the rhizome of A. officinarum contains several flavonoids: quercetin, kaempferol, quercetin-3-methylether, isorhamnetin, kaempferide, galangin, galangin-3-methylether and probably also rhamnocitrin and 7-hydroxy-3,5-dimethoxyflavone.

The crude water extract showed significant in-vivo activity against five sorts of experimentally induced acute ulcers (stress ulcers, Shay's ulcers, aspirin-induced gastric ulcers, mepirizole-induced duodenal lesions and cysteamine-induced duodenal lesions) and two experimentally induced chronic ulcers (acetic acid-induced ulcers and thermocautery ulcers).

An extract from the rhizomes also showed strong antifungal properties. The ethanol extract of the rhizomes was tested in vitro for acaricidal activity on adult tropical cattle ticks (Boophilus microplus) by the dipping method, and 86-100 % acaricidal activity occurred after 5 days. Finally, the methanol extract of the rhizomes was tested for its nematicidal activity on the second-stage larva of Toxocara canis and was found to be active even at a concentration as low as 0.1-0.2 mg/ml.

Several parts of A. galanga yield an essential oil, e.g. the rhizomes contain on dry weight basis about 0.2-1.5%, and on fresh weight basis about 0.1%. The major compound is myrcene, which may account for up to 95% of the rhizome oil. Other constituents of the oil include the pungent galangol (which on distillation gives cineole), and furthermore 1,8-cineole, linalool, geranyl acetate, eugenol, methyl-eugenol, chavicol acetate, 1'-acetoxy chavicol acetate, β-bisabolene, trans-β-farnesene, α-bergamotene, α-pinene and caryophyllene epoxide. The leaf essential oil also contains myrcene (up to 52%), and the seed essential oil contains mainly cineole together with small quantities of citral. In addition to volatile constituents, the rhizome also contains flavonoids: galangin (3,5,7-trihydroxyflavone), galangin monomethyl ether, kaempferol and quercetin.

The essential oil from both fresh and dry rhizomes shows strong in vitro and in vivo antibacterial, antifungal, antiprotozoal, insecticidal and expectorant activities. The water, alcohol or ether extract, but not the petroleum extract, of the rhizome had strong antibacterial properties against Bacillus subtilis, Escherichia coli, Staphylococcus aureus (several strains), Aeromonas hydrophila and Pseudomonas aeruginosa. The alcohol and chloroform extracts, but not the water extract, possessed antifungal activity against Candida albicans, Cryptococcus neoformans, Epidermophyton floccosum, Microsporum gypseum, Trichophyton rubrum, and Saccharomyces sp. The ether extract also had significant effects on Klebsiella pneumoniae.

In addition, the antioxidant and microbial stabilities of an extract of the rhizome (0.01-0.10%) in raw minced beef were examined, and it was found that the extract improved oxidative stability, while the highest concentrations of the extract were also found to extend the shelflife of minced beef. Addition ofα-tocopherol to the extract increased the oxidative but not the microbial stability of minced beef during the storage period of 7 days.

Of the isolated volatile compounds, 1'-acetoxychavicol acetate shows strong antitumour activity in numerous in vitro and in-vivo tests, e.g. against Sarcoma 180 ascites in mice, inhibition of the development of azoxymethane-induced colon tumorigenesis in human cells, and inhibition of endogenous rat-liver carcinogenesis. Other potential anticarcinogenic compounds from the rhizome oil of A. galanga are ethyl trans-cinnamate and ethyl 4-methoxy-trans-cinnamate, which showed significant capacity to induce glutathione S-transferase (GST) activity in mice tissues. A methanolic extract of the rhizome showed potent inhibition of mutagenesis induced by 3-amino-1,4-dimethyl-5H-pyrido[4,3-β]indole (Trp-P-1) in Salmonella typhimurium TA98.

Furthermore, an ethanolic extract of the rhizomes at a dose of 500 mg/kg showed anti-ulcer activity in Shay rats while the chavicol derivatives depressed the gastric secretion of these rats significantly. The extract also significantly reduced gastric secretion and showed marked cytoprotective activity. In another model, the powdered rhizomes were tested for their effect on oxalate urolithiasis in male rats and showed moderate activity.

Acute (24 h) and chronic (90 days) oral toxicity studies on the ethanolic extract of the rhizome of A. galanga were carried out in mice. Acute dosages were 0.5-3 g/kg body weight while the chronic dosage was 100 mg/kg/day. All external morphological, haematological, and spermatogenic changes were recorded, as were body weight and vital organ weights. The weight gain was significant, as well as the rise in the red blood cell level. Also, highly significant gain in weights of sexual organs and increased sperm motility and sperm counts were observed, but no spermatotoxic effects.

The essential oil from the rhizomes of A. zerumbet (from Egypt) was rich in terpinen-4-ol, 1,8-cineole, sabinene,γ-terpinene and fenchyl acetate. A comparable oil distilled in Martinique consisted mainly of terpinen-4-ol (nearly 50%) andα-terpineol. Fresh leaves contain 0.1-0.2% essential oil, with marked quantitative and qualitative differences, depending on their origin. The oil obtained from flowers, originating from Brazil, was dominated by 1,8-cineole (23%), terpinen-4-ol (20%) and sabinene (15%). Furthermore, the seeds contain about 0.4% essential oil, with as main components para-cymene, 1,8-cineole and torreyol, but also the labdane-type diterpenes zerumin A B, as well as (E)-15,16-bisnorlabda-8(17), 11-diene-13-one and coronarin E.

The essentials oils from all parts of A. zerumbet (from Egypt), exhibited significant antimicrobial activity against certain Gram-positive bacteria (Bacillus subtilis, Mycobacterium phlei, Sarcina lutea and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), as well as Candida albicans. Geraniol and isothymol from the essential oil from the rhizome possess high antimicrobial activity against plant pathogenic fungi.

In addition, volatile sesquiterpenes and their derivatives were isolated from the rhizomes of A. zerumbet and A. japonica (Thunb.) Miq. (from Japan). These inhibited histamine- or barium chloride-induced contractions of excised guinea-pig ileum when tested by the Magnus method. Major spasmolytic principles contained in these extracts were sesquiterpenes includingβ-eudesmol, nerolidol, humulene epoxide II and 4-α-hydroxydihydroagarofuran.

Furthermore, from the aqueous extract of the leaves (from Brazil), flavonoids (rutin, kaempferol-3-O-rutinoside, kaempferol-3-O-glucuronide, (+)-catechin and (-)-epicatechin) and lactones of the kava-pyrone type (dihydro-5,6-dehydrokawain (DDK) and 5,6-dehydrokawain (DK)) were obtained. In general, flavonoids are well-known substances that can contribute to the hypotensive and diuretic effects of the aqueous extract of this plant. The kava pyrones have been described as antiulcerogenic and antithrombotic.

As an example, A. zerumbet is used in local medicine as a diuretic and to control hypertension. In a test, a concentrated extract of the rhizome was administrated to 10 healthy volunteers, but only a light significant increase in diuresis was observed, which also lowered the mean diastolic and systolic blood pressure. Furthermore, DK and DDK inhibited the aggregation and ATP release of rabbit platelets induced by arachidonic acid and collagen, without affecting those induced by ADP, PAF and thrombin. This inhibition was reversible and occurred in a concentration-dependent manner. Thromboxane B2 formation caused by arachidonic acid was also suppressed by both antiplatelet agents. The antiplatelet effect of both DK and DDK is therefore likely to be due to the inhibition of thromboxane A2 formation. In addition, the activity of A. zerumbet leaves against stomach-ache, vomiting and dyspepsia has also been attributed to the compounds dihydro-5,6-dehydrokawain (DDK) and 5,6-dehydrokawain (DK). Subsequently, DDK and DK were investigated for their subchronic toxicity in mice and rats and both DDK and DK exhibited a weak sedative activity but their toxic effects were negligible. When an alcoholic extract was injected intra-peritoneally in mice (dose range of 100-1400 mg/kg intra-peritoneally (i.p.), or orally (2500-18000 mg/kg (p.o.)), it produced writhing, psychomotor excitation, hypokinesis and pruritus. Therefore, the LD₅₀ by i.p. route was determined to be about 0.8 g/kg, and 11 g/kg p.o.

Dihydro-5,6-dehydrokawain was also found to be a plant growth inhibitor, causing reduction in hypocotyl length of lettuce (Lactuca sativa L.) seedlings, etiolation and necrosis at increasing dose. DDK also inhibited the germination and growth of Arabidopsis thaliana (L.) Heynh. seeds.

More than 40 constituents are present in the rhizome oil of A. conchigera. The major include β-sesquiphellandrene (20%), β-bisabolene (12%) and 1,8-cineole (11%), but also 1,7-diphenyl-3,5-heptanedione, together with four other diarylheptanoids.

From the essential oil of fresh rhizomes of A. mutica, collected from cultivated plants in Malaysia, 24 components were identified which constituted 88% of the oil, the major components being camphor (36%), 1,8-cineole (9%) and borneol (8%) but also pinocembrin. Chalcone flavokawin B, 5,6-dehydrokawain and 1,7-diphenyl-5-hydroxy-6-hepten-3-one were isolated both from rhizomes of A. mutica and A. rafflesianum, and methyl cinnamate also from A. rafflesianum. The dichloromethane and methanol extracts of A. rafflesianum, A. vitellina, A. malaccensis and A. mutica showed strong antioxidant and antimicrobial activity. The antioxidant activity was comparable with or higher than that ofα-tocopherol.

Steam distillation of the leaves of A. malaccensis yielded up to 0.2% essential oil, consisting mainly of methyl cinnamate (75%). The rhizomes yielded up to 0.3% of a similar essential oil. The essential oil from the seed of A. malaccensis from China contains 1,8-cineole, citronellol, 4-phenyl-3-buten-2-one, geranyl acetate, nerolidol, andα- andβ-farnesol.

The essential oil of the leaves of A. chinensis (from Vietnam), contains more than 40 components, of whichβ-bisabolene (48%) is the major compound. About 30 components were identified from the essential oil of the flowers, of which the main were (E,E)-α-farnesene (27%), α-humulene (22%), β-bisabolene (17%) and β-caryophyllene (13%).

The major components of the leaf oil of the ornamental A. purpurata (Vieill.) K. Schum. are 1,8-cineole (22%), β-pinene (15%) and (E)-methyl cinnamate (13%). The oil obtained from flowers was dominated by β-pinene (28%) and α-pinene (17%).

The Chinese A. oxyphylla Miq. ("bitter cardamom") has been extensively tested for its biological activity. The rhizome contains the following main compounds: diarylheptanoids yakuchinone A and B and oxyphyllacinol, 3 sesquiterpenes, i.e. valencene, nootkanone and nootkanol, 2 flavones, tectochrysin and chrysin, and 2 steroids, β-sitosterol and daucosterol. The structures of the diarylheptanoids are analogous to that of curcumin, which has been widely shown to inhibit tumour promotion in experimental carcinogenesis. Topical application of the methanol extract of dried fruits significantly ameliorated skin tumour promotion as well as ear oedema in mice. Several other findings confirm that A. oxyphylla possesses potential chemopreventive and antitumorigenic activities.

In addition, the acetone extract of the fruits was tested for its anti-ulcer effect. At 50 mg/kg p.o. the extract significantly inhibited HCl/ethanol-induced gastric lesions in rats by 57%. Nootkatone at 20 mg/kg p.o. also inhibited significantly gastric lesions. The effect of a water extract on immunoglobulin E(IgE)-mediated anaphylaxis activated by anti-dinitrophenyl IgE antibody was furthermore evaluated. The results indicated that the extract may possess strong anti-anaphylactic action and also suggest that differential activity following administration routes seen during the experiments may be caused by differences in bioavailability.

Two diarylheptanoids, katsumadain A and B, were isolated from the seeds of A. katsumadai. Both compounds showed anti-emetic activities on copper sulphate-induced emesis in young chickens. An extract of the aerial parts was effective in suppressing the growth of food poisoning bacteria and fungi.

Adulterations and substitutes

The dried powdered rhizome of the primarily medicinally used A. officinarum is often adulterated with the dried rhizome of Acorus calamus L. or A. galanga, and sometimes with other Alpinia or Zingiber species. Several other Zingiberaceae genera contain compounds that also have well-known anti-inflammatory activities, e.g. curcumin from Curcuma domestica Valeton (synonym C. longa L.).

Description

Perennial, erect herbs, with numerous leafy stems, 0.5-4 m tall, rhizomes fleshy, creeping.
Leaves numerous, distichous, lanceolate to ovate, lower and upper ones smallest, finely pinnately veined, subglabrous; usually petiolate, often sheathing; ligule well-developed.
Inflorescence usually terminal on leafy stem, spicate, paniculate or racemose, erect or occasionally drooping, when young usually protected by spathe-like sterile bracts; fertile bracts subtending a cincinnus of 2-many flowers; bracteoles normally present, sometimes tubular.
Flowers bisexual, small to large, red, orange, yellowish to cream or white; calyx tubular, sometimes splitting unilaterally when flower expands; corolla tubular, tube usually not longer than the calyx, 3-lobed, lobes unequal, dorsal one largest, more or less hooded; labellum (anterior staminode) usually large and showy, 2 lateral staminodes small or absent; fertile stamen one, subsessile or with well-developed filament, anther sometimes crested; ovary inferior, 3-locular, surrounded by massive glands, stigma expanded with a narrow, hairy orifice.
Fruit a few-many-seeded, dehiscent capsule, crowned by calyx remnants.
Seed angular, arillate, often aromatic.

Growth and development

After vegetative propagation from a portion of rhizome of Alpinia, a large clump of up to 1 m in diameter may develop within a year. Shoots from pieces of an A. galanga rhizome emerge about 1 week after planting, and 2-3 leaves have developed about 4 weeks after planting. Rhizomes develop quickly and can best be harvested about 3 months after planting when used as a spice. If left longer in the field, they become too fibrous and the large clumps of plants that are formed hamper harvesting. Flowering occurs after exceptionally dry weather. In India, plants start flowering in the latter half of the hot season (April-May) and seeds ripen in November. However, seeds rarely reach maturity. In Java A. malaccensis flowers throughout the year. Alpinia is pollinated by insects, often bees.

Other botanical information

Alpinia belongs to the tribe Alpinieae, which also includes Amomum, Elettaria and Riedelia. Alpinia is a large genus, and there have been several attempts at a subgeneric classification. The most recent classification divides the genus into 2 subgenera, and is based mainly on the character of the labellum (petaloid or non-petaloid). In subgenus Alpinia the labellum is usually concave with incurved margins, commonly striped or spotted, the margins extending into a petaloid area with divergent venation, while in subgenus Dieramalpinia (K. Schum.) K. Schum. the labellum is held erect and almost always closely pressed against the stamen, usually not striped or spotted, lateral margins not well developed, the apex only occasionally expanding into a small petaloid area. Subgenus Alpinia occurs throughout the area of distribution of the genus but has a centre of diversity in continental Asia, and subgenus Dieramalpinia, which is absent from continental Asia and has a centre of diversity in New Guinea and the Moluccas. The largest subgenus, Alpinia, is divided into 7 sections, two of them further divided into several subsections. Subgenus Dieramalpinia is divided into 4 sections, one of them with 2 subsections. All species treated here belong to section Alpinia, but to several subsections.

Several cultivars of A. galanga exist. Those with yellow-white rhizomes are used as a spice, and are about 3 m tall, with stems 2.5 cm and rhizomes 3-4 cm in diameter, while those with pink to red rhizomes are mainly used medicinally, and are about 1-1.5 m tall with stems up to 1 cm and rhizomes up to 2 cm in diameter. White-rhizomed cultivars with similar characteristics to the red-rhizomed ones also exist.

Plants with broad leaves, tomentose beneath, are sometimes distinguished as var. pyramidata (Blume) K. Schum., occurring both wild and cultivated in Java, Borneo and the Philippines.

The identity of A. chinensis is problematic as the type specimen has been lost and its description shows characteristics common both to A. calcarata Roscoe and A. officinarum.

Ecology

Alpinia normally prefers humid, shady conditions and not too high temperatures, at least during the night, e.g. 27-30°C during daytime and 17-18°C at night. They often occur in secondary vegetation, bamboo and teak forest, brushwood and ravines, rarely in primary forest. Near villages, they usually grow in the open. They require rich soils.

A. galanga requires sunny or moderately shady locations. Soils should be fertile, moist but not swampy. Sandy-clay soils rich in organic matter and with a good drainage are preferred.

Propagation and planting

Alpinia is propagated by division of rhizomes, which are planted 50-100 cm apart, and given enough water and liquid fertilizer. Planting is done during the rainy season.

In vitro multiple-shoot production of A. galanga has been successful through excised rhizome buds, cultured on Murashige & Skoog (MS) medium, supplemented with an auxin. On the best medium, 80% of the explants produced on average 7 shoots, and 70% of the shoots produced roots on MS containing 2.5 mg naphthalene acetic acid. The micropropagated plants were transplanted to soil with 75% survival.

A. zerumbet is produced commercially in the United States and Europe as an ornamental and can be propagated by tissue culture.

Husbandry

Alpinia requires cool, shaded conditions; it needs clipping and thinning to keep the plants low.

Diseases and pests

Ginger strain, a bacterial wilt caused by Pseudomonas solanacearum, may attack Alpinia. Alpinia is also sensitive to several root-knot nematodes, like Meloidogyne arenaria, M. incognita and Radopholus similis.

Harvesting

The rhizomes of A. officinarum are harvested in Vietnam at the end of the rainy season. The fruits are collected in July and August. In India, the rhizomes of A. galanga are collected at the end of the rainy season. The dried rhizome of A. galanga is 2.5-10 cm in diameter, reddish-brown skinned, orange-brown inside. It is larger than the rhizome of A. officinarum, and the taste and odour are less pronounced than in the latter species. A. officinarum is whitish inside.

If produced for the market, rhizomes of A. galanga are harvested about 3 months after planting. Whole plants are pulled out, the shoots cut off and the rhizomes washed and cleaned. For local use plants are left in the field and, as they tiller vigorously, small quantities of good quality rhizome can always be harvested. For the production of essential oil rhizomes are harvested when the plants are more than 7 months old.

Yield

An 8-month-old plant of A. malaccensis yields about 1 kg rhizomes and 35 kg leaves.

Handling after harvest

The leaves and rhizomes of Alpinia are used fresh or dried for future use. Whole plants are pulled up, the shoots cut off and the rhizomes washed and dried in the sun or in an oven. The fruits are dried and powdered. The dried rhizomes of A. galanga are usually ground before use, but ground rhizomes are not traded in bulk, as adulteration can occur, e.g. with A. officinarum.

Genetic resources and breeding

The Alpinia species treated here are widespread and common throughout South-East Asia, and therefore not endangered. Neither germplasm collections of Alpinia nor breeding programmes are known to exist.

Prospects

The interesting pharmacological activities of Alpinia, shown by isolated compounds such as the diarylheptanoids and pyrones, merit further research. A combined approach to the future possibilities in medicine, together with their potential as an insecticide, may give rise to cultivation of selected Alpinia species on a larger scale. Furthermore, they are likely to remain important as ornamentals.

Literature

Al Yahya, M.A., Rafatullah, S., Mossa, J.S., Ageel, A.M., Al Said, M.S. & Tariq, M., 1990. Gastric antisecretory, antiulcer and cytoprotective properties of ethanolic extract of Alpinia galanga Willd. in rats. Phytotherapy Research 4(3): 112-114.
Amit, T., Pant, A.K., Mengi, N., Patra, N.K. & Tewari, A., 1999. A review on Alpinia species: chemical, biocidal and pharmacological aspects. Journal of Medicinal and Aromatic Plant Sciences 21(4): 1155-1168.
Chun, K.S., Sohn, Y., Kim, H.S., Kim, O.H., Park, K.K., Lee, J.M., Lee, J., Lee, J.Y., Moon, A., Lee, S.S. & Surh, Y.J., 1999. Anti-tumor promoting potential of naturally occurring diarylheptanoids structurally related to curcumin. Mutation Research 428 (1-2): 49-57.
Perry, L.M., 1980. Medicinal plants of East and Southeast Asia. Attributed properties and uses. MIT Press, Cambridge, Massachusetts, United States & London, United Kingdom. pp. 436-–437.
Smith, R.M., 1990. Alpinia (Zingiberaceae): a proposed new infrageneric classification. Edinburgh Journal of Botany 47: 1-75.
Tanaka, T., Kawabata, K., Kakumoto, M., Makita, H., Matsunaga, K., Mori, H., Satoh, K., Hara, A., Murakami, A., Koshimizu, K. & Ohigashi, H., 1997. Chemoprevention of azoxymethane-induced rat colon carcinogenesis by a xanthine oxidase inhibitor, 1'-acetoxychavicol acetate. Japanese Journal of Cancer Research 88(9): 821-830.

Selection of species

Authors

Halijah Ibrahim