Handbook of Herbs and Spices - Volume 3

(sharon) #1

358 Handbook of herbs and spices


21.1.1 Botanical notes


A. galanga (L.) Sw is a perennial, robust, tillering, rhizomatous herb; grows up to


3.5 m tall, with a subterranean, creeping, copiously branched aromatic rhizome. The


rhizomes are 2.5–10.0 cm thick, reddish brown externally, and light orange brown


internally. The aerial leafy stem (pseudostem) is erect, formed by the rolled leaf


sheaths. Leaves are 23–45 by 3.8–11.5 cm, alternate, distichous, oblong-lanceolate,


acute, and glabrous. Inflorescence terminal, erect, many flowered, racemose, 10–30


¥ 5–7 cm, pubescent; bracts ovate, up to 2 cm long, each subtending a cincinnus of


2–6 greenish white flowers; bracteoles similar to the bracts but smaller; flowers


fragrant, 3–4 cm long, yellow-white. Fruit a globose to ellipsoidal capsule, 1–1.5 cm


in diameter, orange-red to wine red.


Rhizome anatomy shows a central stele surrounded by an outer cortical zone.


Fibrovascular bundles are distributed throughout the cortex and stele. Numerous


resin canals are also present. Its chromosome number is 2n = 48. Much variability


may exist as the species occur naturally in many countries under varying agroecological


situations, however, information is lacking. Cultivars with pink to red rhizomes and


with yellow-white rhizomes are known. The pseudostems of white cultivars reach


about 3 m in height, and the rhizomes 8–10 cm in diameter. The red cultivars that are


more common and widely used, reach 1–1.5 m in height and the rhizomes 1–2 cm in


diameter. Plants with broad leaves that are tomentose beneath are distinguished as


var. pyramidata (Blume) Schuman. This occurs wild and under cultivation in Java,


Borneo and the Philippines (Scheffer and Janson, 1999).


21.1.2 Chemical notes


Tewa r i et al. (1999) reviewed the chemical composition of Alpinia spp. Galangal


rhizome on analysis yielded (per 100 g): moisture – 14 g, total ash – 9 g, matter


soluble in 80% ethanol – 49 g, matter soluble in water – 19 g, total sugar – 9 g, total


nitrogen – 3 g, total protein – 16 g, essential oil content – 0.2–1.5% (dry wt.). Fresh


rhizomes on steam distillation yield about 0.1% of oil, having a peculiar strong and


spicy odour. Earlier investigations indicated camphor, 1, 8-cineole (20–30%), methyl


cinnamate (48%) and probably d-pinene, as the oil components. Scheffer et al. (1981)


analysed a sample from Indonesia and reported 1,8-cineole (47.3%), b-pinene (11.5%),


a-pinene (7.1%), a-thujene (6.2%), terpinen-4-ol (6.0%), a-terpineol, limonene (4.3%


each) and many compounds in lesser concentrations. De Pooter et al. (1985) analysed


a sample from Malaysia and reported (E)-b-farnasene (18.2%), b-bisabolene (16.2%),


a-bergamontene (10.7%), and a-pinene (10.2%) as the important components. Charles


et al. (1992) reported that a sample from the USA yielded 52.3% myrcene, 17.15 (Z)-


b-ocimene, 9.0% a-pinene as the major components. The root contains a volatile oil


(0.5 to 1.0%), resin, glalangol, kaemferid, galangin, alpinin, etc. The active principles


are the volatile oil and acrid resin. Galangin has been obtained synthetically. The


essential oil obtained by hydrodistillation of fresh flowers contains sabinene, limonene,


1,8-cineole, p-cymen-8-ol, patchoulene, (E)-methyl cinnamate, (z)-allylcinnamate,


a-gurjunene and b-caryophyllene (Syamasundetr et al. 1999). Chaudhury (1961),


Nair et al. (1962), Barik et al. (1987) and Kumar et al. (1990) also reported chemical


studies on Alpinia.


The volatile constituents of the rhizomes and leaves of A. galanga from the lower


Himalayan region of India were analysed by GC and GC/MS. The main constituents


identified in the rhizome were 1,8-ciniole, fenchyl acetate and b-pinene. The leaf oil

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