Nature of herb

Pongamia pinnata or Milletia pinnata or more commonly called as Karanja in Hindi is a leguminous and fragrant tree which considered a cousin to Neem. The Karanja Oil offers a spectrum of similar therapeutic benefits to that of its pungent relative while having a milder, pleasant aroma that is much more versatile for use in cosmeceutical applications. Karanja is infamous for its multi-purpose benefits and as a potential source of biodiesel crop. It is known by various other names such as Indian beech in English, Dithouri in Hindi, Pongum in Tamil and Malayam and Honge mara in Kannada. In Sanskrit, it is described by a variety of names such as Karanja, Naktamala, Ghritapoora, Snigdhapatra and Gucchapuspaka.

All the parts of the tree have been used in traditional systems of medicines such as Ayurveda and Siddha for predominantly treating skin diseases. The seeds of the tree are of utmost importance as they yield the highly valued Karanja oil. Karanja oil is reddish-brown in color with a distinctly bitter taste and has an unpleasant smell. It is prized for its emollient properties in skin care, hair care products and is also known to possess anti-microbial, insecticidal, nematicidal activity. Besides the oil yielding capacity the tree is a provider of green manure, fodder and enhances the soil fertility as it is capable of nitrogen fixation, thus making it an excellent candidate for large scale plantations on marginal lands.

Plant Description

Pongamia pinnata is a medium-sized evergreen shrub or tree growing up-to 15-25 m high, with straight or crooked trunk 50-80 cm or more in diameter.

• Leaves
  The leaves are imparipinnate and shiny. Young leaves are pinkish red while mature leaves are glossy and deep green. Leaflets are 5–9 in number; the terminal leaflet is larger than the others with no stipules.
• Roots
  It has a thick tap root system which extends up-to 10 m in the ground to absorb water.
• Trunk
  It has a short and thick trunk with short heavy branches supporting a dense canopy. It has a thin bark which is grayish-brown on the outside while on the inside it is yellow in color.
• Flowers
  Flowers are strongly fragrant being white to pinkish in color and are paired (2-4) along a rachis in axillary panicles while the calyx is cup-shaped.
• Fruits
  Fruits are pods having short stalk and a thick leathery to sub-woody coat. They have an oblong/elliptical shape being 3-6 cm long and 2-3 cm wide.
• Seeds
  Seeds are oblong and are borne singly in a pod. It is 1.7 – 2cm long and 1.2 - 1.8 cm wide and is light brown in color. A tree starts yielding at age of 4-7 years.

Habitat

The tree is native to humid and sub tropical environments viz the Asian sub continent and lowlands in Philippines, Malaysia, USA and Indonesia.

• Climate
  The tree is native to humid and sub-tropic environments, commonly found along waterways or seashores. In its natural habitat, the maximum temperature ranges from 27 to 38°C and the minimum 1 to16°C. It can grow up-to an elevation of 1200 m with the annual rainfall ranging from 500-2500.
• Soil
  This species can grow on a wide variety of soils from sandy to stony soils. It is very tolerant to saline and alkaline conditions and occurs naturally in lowland forest on limestone and rocky coral outcrops on the coast, along the edges of mangrove forest and along tidal streams and rivers. Optimum pH range is 6-8.5. It does not do well on dry sands, even though it can tolerate saline conditions, alkalinity and waterlogged soils.

Usefulness

• A decoction of the leaves is used as a cough remedy.
• An infusion of leaves is used to relieve rheumatism.
• Freshly crushed leaves are used in the treatment of herpes, skin sores, inflammation, constipation and bleeding hemorrhoids.
• It is very useful in treating skin diseases such as eczema, leucoderma, scabies and aids quick wound healing.
• The anti-microbial property is employed to detoxify the vagina. It is also used in treating uterine disorders.
• It can cure worm infestation and aids quick wound healing.
• The leaves are used to relieve inflammation, diarrhea and constipation.
• The fruits are used to treat diabetes and urinary tract disorders.
• The fruits are also used to treat psoriasis and skin infection.
• It helps soothe boils, abscess and eczema.
• It relives pain and inflammation caused due to open wounds and burns.
• Fresh stem bark is used as an astringent and is consumed orally for bleeding hemorrhoids and applied externally incase of spleen enlargement.
• A paste made from Pongamia seeds is given in cases of bronchitis, whooping cough and fever.
• Seed oil can relieve bloating, flatulence and stomach ailments such as dyspepsia and slow metabolism.
• Externally, the seed oil acts as a liniment for rubbing on skin diseases and rheumatic joints.
• Seed oil is also applied externally to the scalp for treating lice.
• The root juice is an anti- septic used for sores and ulcers and also to clean teeth.
• The seed oil is applied over chest in cases of pneumonia.
• It is also an effective remedy against dandruff.

•

• Dried leaves are used as an insect repellent in stored grains.
• Seed oil is used in lamps and cooking.
• Karanja twigs are used as a toothbrush.

Chemical constituents
The tree is rich in flavonoids and rich compounds including simple flavones, furanoflavonoids, chromenoflavones, chromenochalcones, coumarones, flavones glucosides, sterols and triterpenes and a modified phenylaline dipeptide. Seed and seed oil contain karanjin, pongamol, pongapin and kanjone. Additionally, seeds contain lanceolatin B, iso-pongaflavone and pongol. Seed oil contains iso- pongachromene and ponga-gaglabrone.
,br> Flowers contain flavonioids majorly, such as hydroxyl furanoflavones, furanoflavones, triterpenes, beta-sisosterol glucoside and auratiamide acetate.

Cultivation

Pongamia can be succesfully propagated through seeds and stem cuttings. Seeds are viable for upto one year.

• Natural Regeneration
  The tree naturally coppices well and sends out root suckers in natural conditions.
• Artificial Regeneration
  The tree is easily established by direct seedling or by planting nursery raised seedling or stump cuttings of root collar (1-2cmdiameter). Propagation by branch cutting and root suckers can also be done. Fresh seeds yield high germination. Seeds require no treatment before sowing.
• Nursery Practice
  Fresh seeds are sown directly in poly-ethene bags or pots of 20 x 15 cm filled with soil, sand and FYM in the ratio of 2:1:1. Seeds germinate in 10-15 days.
• Planting
  Seedlings of 6 - 12 months old are out planted in the main field into pits with spacing of 30 or 45 cm3at 3m x 3m or 5mx5m. Application of 5 kg FYM at the time of transplantation will enhance growth and establishment.
• Irrigation
  In dry areas watering during the summer months for the first 2 years will give good growth.
• Weeding
  Weeding around the plant is essential for the first three years.
• Pests
  Pongamia tree is affected by several fungal pathogens Fusicladium pongamiae, Microstroma pongamiae, Cercospora pongamiae etc. which cause severe leaf deformities causing white to cream-coloured spots giving a yellowish appearance to the leaves.
  
  This can be prevented by a foliar spray of Neem seed oil .

Commercial Uses

Uses in Ayurveda
Karanja is prescribed in eczema, scabies, leprosy, ulcers, piles, acute constipation, and enlargement of spleen, anorexia, jaundice, biliousness, abdominal abscesses, intestinal paralysis, poisoning and fevers. Karanja seeds with honey are prescribed in internal hemorrhage. The seed oil is used as a laxative, for intestinal worms, skin affections, muscular atrophy, rheumatism and dermatosis. It is also used on the scalp for treatment of baldness. Fruits are prescribed for vaginal and urinary discharges. Flowers are used for diabetes and urinary disorders.
Proprietary Ayurvedic medicines with Pongamia oil extract:

• De Pile ointment: for treating external and internal hemorrhoids.
• Dermasyl skin ointment: used for scabies and eczema.
• Dermafex oil: used in skin infections, psoriasis, eczema etc.
• Erina Plus: used for cleasning the fur/coat of pets( dogs, cats). It prevents the formation of dandruff on the pet's skin and hair coat.

Uses as a biofuel/biodiesel
Biodiesel is an alternative diesel fuel made from vegetable oil which can act as a substitute and additive both for diesel. Pongamia tree is a promising energy crop due to its high seed yield coupled with high oil content. The seed contains 30-40% oil which can be converted to bio-diesel by trans-esterification and is used in diesel generators and is being explored in hundreds of projects all over India and the world as feedstock for biodiesel. Pongamia is well suited for Indian climate and grows naturally throughout the country. It is one of the few crops well-suited for commercialization by India's large population of rural poor. Several un-electrified villages have used Pongamia oil in simple processing techniques and diesel generators to create their own grid systems to run water pumps and electric lighting. It makes for an excellent source of renewable energy as a bio-fuel to meet the ever rising demand for energy and causes less carbon emissions than the conventional sources of energy. Seed oil uses:
The seed contains 30-40% thick reddish brown oil which has a bitter taste with an unpleasant smell. It is used as a lubricant, varnish, water-paint binder, leather tanning and in soap making. Its insecticidal properties also make it great for agricultural use, serving as a natural pest repellent. The seed oil was formerly indispensable as an illuminant in lamps. Two kilos of mature pods will yield about 1 kilo of husked kernels. Extraction of oil is done by cold pressing, solvent extraction and expeller pressing.

Press cakes
Press cakes prepared from the residue after extraction of oil are used as a fertilizer and a natural pesticide for nematodes. It can also be used as animal feed to poulty and ruminants.

Fibre
The bark fibre is made into string, twine or rope, and the wood provides paper pulp.

Timber
It is a moderately strong timber that is relatively easy to saw, turn and finish, the wood is not considered a quality timber because it is not durable, tends to split and is susceptible to insect attack. The wood is used for cabinet making, cartwheels, posts, agricultural implements, tool handles and combs.

Agro forestry uses
Soil erosion: A preferred species for controlled soil erosion and binding sand dunes because of its extensive network of lateral roots. Wind breaker: It is grown as a windbreaker in tea plantations.

Soil reclamation: It can tolerate moderate levels of salinity and drought hence Pongamia is ideal for recovering a variety of wastelands such as saline soil reclamation. It is also used in reforestation of marginal land.

Nitrogen fixing: It nodulates and fixes atmospheric nitrogen thereby increasing soil fertility (nitrogen content).

Manure: Decomposed flowers and leaves are valued as rich nutrition for plants especially in greenhouses.

Ornamental: It is often planted in homesteads as an ornamental tree and in avenue plantings, roadsides and streams and canal banks.