KARANJ (PONGAMIA PINNATA) – AN AYURVEDIC AND MODERN OVERVIEW

Pongamia pinnata is one of the significant herbal plants with different therapeutic medicinal properties. P. pinnata is a potential medium-sized legume tree, also known as Karanja. It is widely distributed in Indian Western Ghats. This plant is mostly cultivated around coastal areas, riverbanks, tidal forests, and roadsides. Conventionally, the leaves, seeds, and the whole plant were utilized in the treatment of many ailments. There are various phytochemicals isolated from the P. pinnata plant. Karanjin is the principal furanoflavonoid of the plant. It was known to be the first crystalline compound isolated from this plant. The plant is therapeutically important in traditional medicine as well as in modern drugs. Oil extract from the P. pinnata seeds is utilized in agriculture and pharmacy. Seed oil is also proved to be a biofuel in recent studies. There are various therapeutical uses of the P. pinnata, including antiulcer, anti-diarrheal, antiplasmodial, anti-inflammatory, anti-viral, anti-bacterial, anti-lice, and others. The karanja seeds contain 27-40%(w/w/) oil. Commercially, the seed oil of the P. pinnata is used as biodiesel. The present review article reveals the overall ayurvedic and modern therapeutic information of P. pinnata with various reported ayurvedic literature and scientific pharmacological studies.


INTRODUCTION
Medicinal plants play an important role in human lives for many years to treat various diseases all over the world. Plants are the diverse producer of bioactive compounds that make them a rich source of different types of medicines [1]. Today, there is widespread interest in drugs obtained from natural plants for their various therapeutic properties. Pongamia pinnata Linn Pierre (Fabaceae) is a fast-growing medium-sized tree that belongs to the Leguminosae family [2]. It is an important non-edible minor oilseed tree. It is also called as "Karum Tree" or "Poonga Oil Tree" in English [3]. It is native mainly to hot arid regions of Asia. The trees Pongamia are cultivated commercially in India. Therapeutic uses of this plant are also found in the literature of the traditional medicinal system. Karanja (P. pinnata) (Fig. 1) is an ancient plant of Veda, Samhita, and almost in all Nighantu (Dictionary) [4]. It includes various chemical compounds such as alkaloids, flavonoids, tannins, glycosides, hormones, karangin, glabrin, kanugin, fixed oils, and others [5] that possess various potential anti-inflammatory, anti-nociceptive, antioxidant, antidiarrheal, anti-fungal, anti-plasmodial, anti-ulcer, anti-hyperglycemic, anti-oxidative, anti-hyperammonemic, and analgesic functions [6,7]. All parts of the plant P. pinnata have been considered as a crude drug [8]. It is also used in the field of environment and agriculture. The seeds of the plant are known as potential biodiesel sources [9] that contain around 28-34% oil with a high concentration of polyunsaturated fatty acids [10]. P. pinnata contains a dense network of lateral roots that have been known to prevent soil erosion. There are several methods reported for the cultivation of plants, including direct seed sowing or by raising the seeding in the nursery and planting by stump cuttings. However, seed sowing is most common because it does not require pre-treatment and grows within 1 week to a month [11]. The tree has a vast medicinal, economical significance due to widespread usage of every part, especially seeds and roots [12]. This review paper aims to provide whole information on the general information, phytochemicals, and various medicinal application of the plant P. pinnata. Taxonomy and vernacular names of P. pinnata (L.) are given in Tables 1 and 2, respectively.

Chalcones
Twenty-five compounds are dominated by furanochalocones and chromenochalcones and come under chalcone class. They are written below: • Root Bark: 2′-hydroxy-3,4,4′, 6′-tetramethoxychalcone, Ponganone X, Milletenone, Ponganone VII, Dihydromilletenone methyl ether, Ovalitenin B, Ponganone IX, Glabrachromene, and Ovalitenone are the chalcones compounds isolated from P. pinnata • Stem: Tunicatachalcone, 7-methoxypraecansone B, Pongapinone A, Glabrachromene, and Ovalitenone have been isolated from this plant. Furanoflavone is first isolated from the seed oil. Limaye (1925) was succeeded to obtain their structure [17]. He proved that the molecule of Karanjin consisted of 3 fused rings, of which at the center, the carboxylic benzene nucleus had on either side one ring each, containing oxygen atoms besides carbon. There is a total of 13 colorless crystals in which simple flavone such as fisetin tetramethyl ether, 3,7-dimethoxyflavone, Luteolin, 7-O-methylchrysin, 7,4′-dimethoxy-5-hydroxyflavone, Kaempferol, and quercetin have been isolated from all the parts of the plant, except the seed. Kaempferol is recent to be isolated from P. pinnata [18]. Kanugin is a methylenedioxy flavone that was also extracted from roots, flowers, stem bark, and other parts of the plant. Demethoxykanugin loses a methoxy group attached to the B ring extracted from the flower, stem bark, and root bark [19][20][21][22].
Pongapin is the second furanoflavone found in the species that were isolated from the root bark [23]. After that, several farina flavones have

Miscellaneous compounds
Several miscellaneous compounds were also reported to occur in all parts of this plant [27]. Terpenoids exist as sesquiterpene, diterpene, and triterpenes. Most of the terpenes are detected in the stem bark except Cycloart-23-ene-3β,25-diol and Friedelin, which were isolated from the flower part. β-sitosterol and stigmasterol along with their acetate are Thakur et al.   Shameel et al. (1996). Bis (2-methylheptyl) phthalate, an aromatic ester, was the only miscellaneous compound found in this plant reported to occur in the leaves [2,46].

Folk view
Karanja plant is a medicinal plant since ancient times. According to Hartwell (1967Hartwell ( -1971, in India, the sprouts and fruits are utilized in folk remedies for abdominal tumors, the seeds for keloid tumors in Sri Lanka and plant powder are used for tumors in Vietnam [17]. Every part of the plant having ethnobotanics properties. The seed oil of P. pinnata is utilized in itches, abscesses, and other skin diseases [47]. Flowers are used as a remedy for diabetes problems [19]. Bark of the plant is used internally for bleeding piles, beriberi and diabetes, and anti-hepatoprotective activity [20]. Leaves were used as a medicated bath for relieving rheumatic pains and for cleaning ulcers in gonorrhea and scrofulous enlargement [48]. Roots are used for cleaning gums, teeth and ulcers, and other dental problems [49].

Ayurvedic view
The "pongam tree" is known as one of the richest and brightest trees in India. The word "pongamia" has derived from the Tamil word "pinnata" that refers to the "leguminosae" family. In Hindi and Bengali, it is known as Karanj or Paper or Kanji [50]. It is classically categorized in Charaka Samhita as a "Kandughna" that means a group of herbs that relieve itching, Katuka Skandha is a pungent tasting group of herbs. Charaka has mentioned it as a major source of oil [51,52]. Rasa Panchak of Karanj as per Ayurveda is shown in Table 3.
Pongamia oil is a major source of bio-diesel and is used in Ayurveda for external application to shrink the pile mass, to heal wounds and abscesses quickly. It is useful in acne vulgaris, pimples, and secretions [56].

MODERN VIEW
The consumption of herbal medicines has increased nowadays world widely. Reported studies have revealed an increased growth in the sale of herbal products from the year 2000 to 2008 ranges from 3% to 12% per year [57]. Due to the increased demand of herbal products, the risk with herbal medicines also rises. The quality of the end product compromises because of the contamination of raw material with toxic metals, microbes, other residues, and adulteration (addition of fake or inferior plant material, orthodox drugs, foreign material) which results in poor quality of medicinal products [58]. Internal issues such as non-uniformity (rises due to environmental factor and geographical distribution, use of pesticides, fertilizers) and complexity in the Thakur et al.
ingredients of herbal medicines are also raised which affects the quality of herbal medicines [59]. Lack of standardization technique for herbal products is also responsible for the poor quality of drugs because of the failure to detect the original drug which exploits its usage in the conventional system of medicines [60]. The development of new dosage forms without affecting the principal component is the presentday need. Many formulations such as oil, creams, and seed packet are produced from the plant P. pinnata. Seed oil has its own medicinal value, due to which it is used for the treatment of rheumatism in humans. Modern science utilized its effect for enhancing the pigmentation of skin in humans affected by leukoderma or scabies [7]. The oil is also used as a lubricant, water-paint binder, pesticide, and in soap-making and tanning industries [7].

PHARMACOLOGICAL AND THERAPEUTIC USES
Several scientific research/studies showed that this plant consists of various pharmacological activities such as antioxidant, antimicrobial, anti-parasite, anti-inflammatory, anticonvulsant, anti-diabetic, antihyperammonemia, cytotoxicity, anthelminthic, and many others. They are mentioned below: 1. Anti-oxidant properties: The ethanolic extract of the leaves mainly possesses anti-oxidant properties. The experiment was conducted in NH 4 Cl-induced hyperammonemia rats and results showed that oral administration (300 mg/kg wt) significantly reduced the level of TBARS, HP, and CD and increased the level of superoxide dismutase, catalase, glutathione (GSH) peroxidase, and GSH in the liver and kidney [61]. The flavonoids and polyphenol present in the extract have anti-oxidant properties. One more research states that methanolic extract of the seed increases the level of ferric reducing/ antioxidant power [ [63]. Chalcone, triterpenes, and aromatic carboxylic acid are the major compounds that possess antimicrobial activity [64]. A test was conducted to evaluate the antifungal property of the plant and it was found that seed oil showed maximum activity against Aspergillus niger followed by Aspergillus terreus and Candida albicans [65]. Cycloart-23-ene-3β,25-diol is a triterpene compound of this plant which is tested for its antifungal activity. The result showed strong activity against C. albicans and no any action against Penicillium notatum [66]. The crude aqueous extract of the seed hindered the growth of herpes simplex virus type-1 (HSV-1) and HSV-2 [67] and showed no any activity against rotavirus [68]. An experiment has shown that oral administration of ethanolic extract of leaves hinders the growth of white spot syndrome virus and increased the survival rate in shrimp up to 40-80%, respectively [69-73] 3. Antiprotozoal: Reported studies revealed that the bark and leaf extract with low IC 50 values dry extract showed anti-malarial, antiplasmodial activity against Plasmodium falciparum [74]. Lupeol is the main constituent that blocked the invasion of P. falciparum merozoites [75,76] and also inhibited the growth of Trypanosoma cruzi and Leishmania [77] 4. Anti-inflammatory: An experiment was conducted in the rats to evaluate the anti-inflammatory activity of methanolic extract of the seeds which were administrated orally in the dose of 12-50 mg/kg for the 5 days. The results showed protective effects against a gastric ulcer in the rats [78,79]

Another study was conducted to evaluate the anti-inflammatory
activity against Freund's complete adjuvant-induced arthritis in rats. It was found that the model injected with this polyherbal formulation containing roots of Cissampelos pareira Linn, leaves of M. pinnata (L.) Pierre, and leaves of Vitex negundo Linn. possesses anti-inflammatory properties [80]. This formulation reduces the hind paw swelling and body weight with other improvements in the model 6. Anticonvulsant activity: The experiment was conducted for the treatment of maximal electroshock-induced seizure in Wistar albino mice with the ethanolic extract of the leaves. It was found anticonvulsant property by lowering the duration of extension phase when compared with a control group. Hence, the ethanolic extract of the leaves of this plant have anticonvulsant activities [81,82] 7. Anti-hyperammonemic activity: The level of blood ammonia, circulatory urea, uric acid, non-protein nitrogen, and creatinine decreased significantly in the rats treated with the extract and ammonium chloride. No significant change in the body of the model was found when compared with the control [69] 8. Cytotoxicity: 100 mg/ml methanolic extract was screened to know the cytotoxicity against the pancreatic adenocarcinoma cell line Panc-1 (human pancreatic cancer) for cytotoxicity. It was used as a label-free biosensor assay. The extract of this plant exhibited antiproliferation activity [83]. . Cardioprotective activity: A study was conducted for the investigation of the cardioprotective activity of P. pinnata in diabetic rats. Diabetes in rats was induces with streptozotocin-nictinamide. As a result, it was found that the stem bark petroleum ether extract was effective on cardiomyopathy in rats [87] 12. Antinociceptive and antipyretic activity: Reported studies state that leaves have antinociceptive and antipyretic behaviors. An experiment was conducted to test the antinociceptive efficacy by injection of 70% ethanolic extract in the pain models in rats and mice. The finding showed that the leaves have antinociceptive and antipyretic activity [88] 13. Anti-diabetic activity: The flower extract of the P. pinnata administrated orally in diabetic rats significantly decreased blood glucose levels to a degree close to that of the drug glibenclamide.
The finding displayed an anti-hyperglycemic effect and also raised the level of plasma insulin significantly [89] 14. Neuroprotective activity: A study showed the neuroprotective impact of stem bark ethanol extract on monosodium glutamate-induced neurotoxicity in albino rats [90] 15. Anti-lice activity: According to recent studies, this medicinal plant is the novel anti-lice agent. An experiment was conducted in which different extracts of P. pinnata leaves in the sample checked against head louse Pediculus humanus capitis. The outcome indicated the anti-lice activity [91,92] 16. Anti-ulcer: Reported studies showed that the methanolic extract of roots of P. pinnata tends to decrease acetic acid-induced ulcers. Ulcer protective effect of methanolic extract of P. Pinnata roots was due to augmentation of mucosal defensive factors such as mucin secretion, the life span of mucosal cells, mucosal cell glycoproteins, and cell proliferation [7]. Reported studies on P. pinnata are listed in Table 4.

SEED OIL AS BIOFUEL
P. pinnata plant is considered as a source of biodiesel. Oil is extracted from the seeds of the P. pinnata. Seed oil is a thick, yellowish, or reddishbrown having calorific value of 40.756 MJ/kg. The oil is extracted through expeller and solvent extraction. The seeds of karanja contain at least 27-40% of oil. There are many factors affecting the quality of the oil (biodiesel) such as viscosity, flash point, calorific value, specific gravity, and acid value/free fatty acid content [93]. The free fatty acid content is very high in seed oil of karanja. Biodiesel produced through 2-step transesterification process. The Karanja oil also undergoes in 2 step processes in which acid-esterification done before alkali transesterification [94]. In some supercritical conditions, both the steps can be carried out simultaneously because of the shortage of time [95].

CONCLUSION
Nature has been a good source of medicinal plant since immemorial time. At present, many modern drugs have been isolated from the plant source. Karanja has been recognized as a medicinal plant in a traditional system for the treatment of various diseases of human beings. Many scientific studies have proved the pharmacological activities of the P. pinnata such as anti-ulcer, anti-diarrheal, antiplasmodial, antiinflammatory, anti-viral, anti-bacterial, anti-lice, and many more. Apart from the multiple biological effects, seed oil obtained from this plant is proved to be biodiesel as per recent studies. Conclusively this plant herbal plant is proved to be a multipurpose tree with good economic value.

AUTHORS' CONTRIBUTIONS
We declare that this work was done by the authors named in this article and all liabilities pertaining to claims relating to the content of this article will be borne by the authors.
Dr. Gitika Chaudhary drafted the article and contributed in writing Ayurvedic view of the article Dr. Hemlata Kaurav contributed in drafting and writing pharmacological portion of plant. Shifali Thakur contributed in data collection and writing the paper.

CONFLICTS OF INTEREST
No potential conflicts of interest were reported by the authors.

AUTHORS' FUNDING
No any funding for this article writing. . The transesterification process addresses some issues like high viscosity, same as other vegetable oils. Therefore, the karanja oil is not suitable for direct use in a diesel engine. After addressing these issues by this process, the quality of karanja oil methyl ester (biodiesel) is produced that is also cost-effective. There is a various method for the production of biodiesel from the karanja oil such as pyrolysis, micro-emulsion, and bleeding [96]. In recent years, Karanja oil is considered as a good commercial option over other mineral fuels. Mofijur et al. showed in his research that the use of various anti-oxidants in the karanja oil improves the oxidation stability, cost-analysis of biodiesel [97].