CLOVES: GOOD FOR VIRAL, BACTERIAL & FUNGAL INFECTIONS

Botanical name: Syzygium aromaticum

Synonyms: Eugenia aromatica, E. caryophyllus, Myrtus caryophyllus

Indian names:      Laung (Hindi, Punjabi, Gujrati, Marathi), Lavanga (Kannada), Kirambu (Tamil), Lavangamuchettu (Telgu), Karayampu, Krambu (Malayalam)

Family:       Myrtaceae

Chromosome No:  2n= 22

Clove (Syzygium aromaticum) is one of the most ancient and valuable spices. The clove of commerce is dried, unopened and aromatic flower buds of an Oriental tree. As the flower buds resemble irregular nails, the word ‘clove’ is considered to be derived either from the Latin or French words clavus or clou (meaning nail). Indonesia (production about 50,000 tonnes),  Tanzania, Indonesia, Madagascar, Cameroon and Sri Lanka are the major producers and clove-exporting countries. In India, clove is cultivated to Kerala, Tamil Nadu, Karnataka, Andaman & Nicobar Islands. The world production of clove is at around 80,000 tonnes per annum. Saudi Arabia, USA, France and India are the major clove importing countries in the world. In India, 2340 hectares of land is under clove cultivation and annual production is around 1200 tonnes. Clove has a calorific value (energy) of 286 and 159 kilo calories for dry and fresh cloves respectively.

Origin and Domestication

Cloves are native to Moluccas or Maluku Islands (known as Spice Islands) in Indonesia. Many archeological findings point out that cloves were traded even in the pre Christian era. Samples collected from Syria are dated back to 1721 BC. Cloves were traded by Muslim sailors and merchants during the Middle Ages through sea routes.

 Morphology

Clove plant is a medium-sized evergreen tree growing to a height of 10–20 m. It can live up to 100 years or more. The stem is much branched and has grey bark. The leaves are elliptical in shape and arranged oppositely. Leaves are highly aromatic due to presence of oil glands containing volatile oils. Flowers are borne in terminal cymes with three flowers in each group. Flowers are highly fragrant, crimson-coloured and borne on a cylindrical base. The flowers are bisexual having four sepals, four petals, numeral stamens and a single carpel. Sepals are surrounded by fleshy hypanthiums. The fruit is 1.5-2.5 cm long purple drupe.

 Cultivation

Clove is a tropical plant which thrives well in warm and humid climate. A temperature of 20-30°C and an annual rainfall of 150-250 cm is best for its cultivation. It can grow well on deep and rich loamy soils. Plant is propagated through seeds. Naturally fallen mature fruits are collected and sown directly in nurseries ad they loose viability within one week only.  Seedlings, about two years old, are transplanted in the field in well prepared and manured pits. However, it is a slow growing plant and takes very long to bear flowers. It starts bearing flowers when the plants are 8-10 years old but full bearing stage is achieved in about 20 years. Flowering takes place from September- October (in plains) or December-February (hills). The flower buds become ready for harvesting in about four months. The unopened flower buds are picked by hand when they start turning into pink from green. They are dried and packed. A fully grown tree produced about 2 kg of dried cloves annually.

 Chemical Constituents

The characteristic aroma and flavour in clove is due to the presence of biomolecules eugenol and eugeneyl acetate. Good quality clove buds contain 15–20% essential oils dominated by eugenol (70–85%), eugenyl acetate (15%) and β-caryophyllene (5–12%). The other constituents are methylamylketone, methylsalicylate, α- and β-humulene, β-ylangene and chavicol.

In broad overall chemical constitution, cloves consist of 61% carbohydrates, 20% fat, secondary metabolites, vitamins and minerals. Cloves are best when used whole. Their flavour and quality deteriorates once powdered.

Uses

1.      As Spice: Cloves are widely used in curry powders and masalas. They are used in almost every dish or cuisine made in North India. They are mostly mixed with other spices. They find extensive use in ‘biriyanis’ to enhance flavour of the rice in South India.

2.      Flavouring of Meat: Whole and ground cloves are used to enhance the flavour of meat and rice dishes.

3.      Medicinal Uses: Cloves are highly valued in medicine. They are reported to have carminative, antispasmodic, anodyne (painkiller), antipyretic, stimulant, anti-inflammatory, natural anthelmintic, antibacterial, antiviral and antifungal properties. The medicinal properties of clove are due the presence of eugenol. They are important component of Indian Ayurvedic medicine, Chinese medicine and western herbalism. Traditional Ayurvedic healers in India have used cloves since ancient times to treat respiratory and digestive ailments. Zheng et al. (1992) reported that sesquiterpenes, β-cayophyllene, a-humulene and eugenol present in clove oil have potent anticarcinogenic activity (through induction of detoxifying enzyme glutathione-S-transferase) in mouse.

4.      Incense Material: They are an important incense material in Chinese and Japanese culture.

5.      Clove Oil: Oil extracted from cloves is used extensively for flavouring of meats, sausages, baked goods, confectionery, candies and table sauces. Clove oil is also used in aromatherapy and to treat toothache.

6.      Industrial Applications: Clove oil is extensively used in toothpastes, perfumes, chewing gums, soaps and mouthwashes. It is also used as a clearing agent in histological studies.

CINNAMON: A MEDICINE FOR COUGH, COLD & CHOLESTEROL

Botanical name:   Cinnamomum verum (Synonym: Cinnamomum zeylanicum)

Indian names:    Dalchini (Hindi, Punjabi, Gujrati, Bengali, Telgu), Tamalapatra (Sanskrit), Lavangpatti (Kannada), ilayangam,  Cannalavangapattai (Tamil)

Family:                Lauraceae

Chromosome No:  2n= 24

Cinnamon is a spice obtained from the inner bark of several tree species from the genus Cinnamomum. However, true cinnamon known as Ceylon cinnamon is obtained from Cinnamomum verum. Cinnamon possesses a delicate and spicy aroma due to presence of volatile essential oils such as cinnamaldehyde and eugenol. Cinnamon is among the earliest and popular spices used by mankind. Ceylon cinnamon, a native of Sri Lanka, is cultivated in the lower elevations of Western Ghats in Kerala and Tamil Nadu. Sri Lanka is the major country growing Ceylon cinnamon (considered best quality cinnamon) on an area of about 24,000 hectares and  producing 12,000 t quills (long, compound rolls of cinnamon bark) per year. Total world production of cinnamon at present (FAOSTAT, 2016) is about 223,575 tonnes per annum. Top cinnamon producing countries (all types of cinnamon) are Indonesia (91,300 tonnes),  China (77,055 tonnes),  Vietnam (35,516 tonnes),  Sri Lanka (16,931 tonnes) and  Madagascar (2,460tonnes).

 Origin and Domestication

The true cinnamon, Cinnamomum verum, is a native of Sri Lanka and South India. The source of cinnamon remained a mystery to the Western world in the medieval times and was thought to be brought from Red Sea to the trading ports of Egypt. The source of cinnamon became known to the western world only at the end of thirteenth century. The Dutch traders controlled the entire business of cinnamon in Sri Lanka by 1640. Lord Brown of the British East India Company established Anjarakkandy Cinnamon Estate in Kannur (then Cannanore) district of Kerala in 1767.

                        (Photo source: Wikipedia)

 Morphology

Cinnamon (Cinnamomum verum) plant is a small evergreen tree growing to a height of 10-15 m. However, plants in cultivation are small and bushy due to regular trimming. The stem is highly branched and covered with thick grey bark. The bark tissue is characterized by presence of secretion cells containing mucilage or oil. The leaves are variable in size, opposite, ovate-lanceolate or elliptic in shape and 7–18 cm long. They are triplinerved with the two basal lateral nerves reaching the tip of the leaf. Oil  and  mucilage  cells  are  always  present  in  both  the mesophyll  layers. The inflorescence is a panicle with pale yellow or greenish-coloured small flowers. Flowers are  actinomorphic,  bisexual and  trimerous. The perianth is arranged in two whorls of three each. Androecium is made up of 9 stamens arranged in three whorls. A single carpel has one superior ovary with one pendulous ovule. Fruit is a fleshy, one-seeded, ovoid and black or purplish black-coloured berry.

Cultivation

Cinnamon is a hardy plant and can be grown on a wide range of soil types and under climatic conditions. It is grown on laterite and sandy soils with poor nutrients in the West Coast of India. Cinnamon is mostly grown as a rainfed crop. An annual rainfall of 200-250 cm, warm weather and altitude up to about 1,000 m is ideal for its cultivation. It is propagated through stem cuttings, air layering and seedlings. Semi hardwood cuttings of about 10 cm length with 2 leaves are more successful and give better results. Cinnamon tree is grown for about two years and then coppiced (cut) to the ground level. The harvested shoots are processed into cinnamon of commerce. Many new shoots (about a dozen) arise from the roots to replace those that were cut to the ground. About two years old shoots are again cut to the ground level and again processed. This process continues for many years.

Different Species of Cinnamomum

Many different species of Cinnamomum are often sold as cinnamon in the markets. They are:

1. Cinnamomum burmannii (Indonesian cinnamon)
2. C. cassia (Cassia or Chinese cinnamon, most common commercial type in Indian market)
3. C. citriodorum (Malabar cinnamon)
4. C. loureiroi (Vietnamese cinnamon)
5. C. tamala (Indian cinnamon, Tejpatta)
6. C. verum (Sri Lanka cinnamon or Ceylon cinnamon)

Processing

The shoots are harvested and cut into straight pieces of 1-1.25 m length. They need to be processed immediately after harvesting when the inner bark is still wet. The rough outer bark of the harvested stem is scraped off. Thereafter, peeling is done by using a specially made knife, which has a small round end with a projection on one side to facilitate ripping of the bark. A longitudinal slit is made on the stem from one end to the other.  The bark can be easily separated by working the knife between the bark and the wood. The separated bark is first dried in the shade for one day and thereafter in the sunlight for next four days. The separated bark contracts and assumes the shape of a quill during the process of drying and hence called quill. The dried quills are cut into 5-10-cm lengths and packaged for sale.

 Improved Varieties

Nithyasree and Navasree

 Chemical Constituents

Cinnamon possesses a delicate and spicy aroma, which can be attributed to the presence of volatile oils. The major component of leaf oil is eugenol, while that of bark oil is cinnamaldehyde. The volatile components can be broadly classified into monoterpenes, sesquiterpenes and phenylpropenes. The volatile oil content in the bark of Ceylon cinnamon varies from 0.4 to 2.8% and contains 75% cinnamaldehdyde, 5% cinnamyl acetate, 3.3% caryophyllene, 2.4% linalool and 2.2% eugenol. In leaf, volatile oil content varies from 0.24–3.0% and contains 65 to 92%eugenol. On the other hand, both leaf and bark oils of Chinese cassia contain mainly cinnamaldehyde (60-90% of the oil content).

General chemical composition of bark is:  carbohydrates 59.5%, protein 4.6%, fat (ether extract) 2.2%, fibre 20.3%, total ash 3.5%, calcium 1.6%, phosphorus 0.05% and other minerals.

 Uses

1.      Universal Spice and Condiment: The inner bark of cinnamon tree is used as a condiment for flavouring foods, meat, sweats and other food stuffs.    Cinnamon and sugar are used to flavour cereals and bread-based dishes in the United States.

2.      Cinnamon Oil: Volatile oils such as eugenol and cinnamaldehyde obtained from cinnamon bark and leaves are used in perfumes, incenses, confectionary, chewing gums, chocolates in Mexico and other food items. It is also is  used  for  flavouring   pharmaceuticals and soaps.

3.      Medicinal Uses: Cinnamon has a long history of use in traditional medicine in various parts of the world. It is used as an ingredient in many Ayurvedic and Unani medicinal preparations. It has been proved to be useful in cough, cold, diabetes and in regulating cholesterol. Cinnamon possesses various biological activities, such as expectorant, carminative, antioxidant, antimicrobial, antidiabetic, immunomodulatory, anti-inflammatory, antipyretic, analgesic and anti-allergic.

4.      Insecticidal activity: Cinnamon oil possesses insecticidal properties.

5.      Nematicidal activity: Cinnamon oil also possesses nematicidal activity against some nematodes.

6.      Flavouring of Alcoholic Drinks: Cinnamon oil is used for flavouring alcoholic beverages, such as wines, whisky, vodka and brandy.