Indigofera tinctoria: History, Distribution, Habitat, Classification Characteristics, Phytochemical Constituents, and Medicinal uses
Introduction
The plant Indigofera tinctoria is a member of the Fabaceae family, sometimes referred to as Neeli in Tamil and found all over India. The majority of the 700 species in this group are tropical natives. The shrub Indigofera tinctoria L., sometimes known as “indigo” or “Nili,” is an annual, biennial, or perennial that grows spontaneously throughout India and is hardly cultivated for commerce. The entire plant species and its parts have been used. The leaves and twigs generate a colourless precursor from which the blue dye indigo, used in the textile industry, is derived. The plant species is very significant since it contains vital phytochemical components in addition to producing dye and having therapeutic benefits. Indirubin and indigtone, found in leaf juice extracts, are crucial for treating hydrophobia. It also has anti-diabetic, anti-hepatoprotective, anti-hyperglycemic, antibacterial, anti-antioxidant, anti-cytotoxic, anti-epilective, antinociceptive, anthelminthic, antiproliferative, and anti-dyslipidemic effects, among others.
History
The first European to describe the indigo-making process in India was Marco Polo (13th century). Beginning in the Middle Ages, indigo was frequently utilised in European easel painting.
Distribution and Habitat
The native environment of this plant is uncertain because it has been cultivated for many centuries all over the world. It has naturalised in tropical and temperate Asia, as well as some regions of Africa.
Classification
Kingdom: Plantae
Division : Magnoliophyta
Class : Magnoliopsida
Order: Fabales
Family: Fabaceae
Genus: Indigofera
Species: L.tinctoria
Scientific name : Indigofera tinctoria
Parts Used: Whole Plant
Characteristics
1. The plant is a shrub up to 2m high with 7-13 leaflets.
2. The plant is primarily found as leaflets and fragments of rachis; leaflets are 1-2.5 cm long and 0.3 to 1.2 cm wide, oblong to oblanceolate with a very short mucronate tip, pale green to greenish-black, and lack distinctive odour and flavour.
3. The leaf petiole has two lateral wings and a nearly circular appearance. It has a single-layered epidermis covered externally by a thin cuticle and followed internally by single-layered collenchymatous cells. It also has a continuous or discontinuous pericycle, three vascular bundles, one large one in the centre and two smaller ones in the lateral wings, and a pit made up of round to oval, thin-walled parenchymatous cells with a few
4. Midrib – Epidermis, cuticle, and hair are visible on the midrib, identical to those on petiloes. Below the epidermis, on each side, there may be a single or two or three layers of collenchyma, which are both followed by two or three layers of thin-walled parenchyma.
5. Lamina: Demonstrate dorsiventral structure; epidermis, cuticle, and hair, comparable to those of the petiole and midrib; There are 2-3 layers of the palisade, 2-4 layers of spongy parenchyma, a few patches of veins strewn between the two, and mesophyll cells occasionally contain prismatic calcium oxalate crystals. Paracytic stomata and hair are present on both surfaces but are more prevalent on the bottom side.
5. It bears sheaves of pink or violet flowers as well as light green, pinnate foliage. Compound leaves are 2.5–11 cm in length and have 9–13 leaflets. The opposite leaflet blades are obovate-oblong to obovate, 1.5-3 x 0.5-1.5 cm, both surfaces with appressed medifixed trichomes, above occasionally hairless, base broadly wedge-shaped to rounded, and the tip rounded to notched. The leaf stalk is 1.3-2.5 cm; the spikelets are minute; the leaflet stalks are about 2 mm.
6. Flowers are produced in racemes that are 2.5–5 cm long, laxly flowered, lack a flower cluster stem, and have bristly, mm-long bracts. The 4-5 mm flower stalks in the fruit are reflexed.
7. The calyx is roughly 1.5 mm long and has trichomes and triangular teeth that are as long as a tube. Flowers are red; standard broadly obovate, 4-5 mm; wings are about 4 mm, and the keel is as long as wings. Outside are covered in brown trichomes. Heart-shaped anthers; stamens 4-5 mm. bald ovaries.
8. Pods are 2.5–3 cm long, deflexed, straight to semicircular, never sickle-shaped, hairy or hairless, and the endocarp is blotched with purplish red.
9. A legume has 5–12 cubic, 1.5 mm thick seeds.
10. Flowering: all year
11. I. tinctoria contains the rotenoids deguelin, dehydrodeguelin, rotenol, rotenone, tephrosin, and sumatrol.
Biological Source
Nili (leaf) is made up of dried leaves of the Fabaceae family plant Indigofera tinctoria Linn. A common and frequently grown shrub, Indigofera tinctoria, is between 1.2 and 1.8 metres tall and can be found all over the country.
Phytochemical Constituents
Galactomannan has been isolated from seeds and is only partially characterised by flavonoids, terpinoids, alkaloids, glycosides, indigotine, indiruben, and rotenoids
Medicinal uses
1. It is used to treat a variety of conditions, including glowing skin, sores, ringworm, blisters, hair regrowth, naturally darkening hair, poisoning of the urinary system, mouth ulcers or canker sores, kidney disease, insects in the ear, black hair and hair loss, and dog bites.
2. The bitter, laxative, trichogenous, expectorant, anthelminthic, hepatoprotective, anticancer, epilepsy, neuropathy, chronic bronchitis, asthma, ulcers, skin disorders, and diuretic properties of Indigofera tinctoria’s roots, stems, and leaves are also helpful for encouraging hair growth. The juice collected from the leaves of the plant, which was discovered to contain indirubin and indigtone, is effective in treating hydrophobia.