places exhibiting whitish patches, internally smooth and transversely corrugated, dark blackish-brown externally and greyish-yellow internally, fracture short and brittle. Taste bitter and odour characteristic.

Microscopical study:

TS of root bark shows well developed rhytidoma composed of zigzaggedly running cambium alternating with suberized cork and lignified oval to round parenchyma, multilayered radially arranged suberized cork, narrow cortex consisting of 15 to 20 rows of tangentially running parenchymatous cells containing simple and compound starch grains, prismatic crystals of calcium oxalate and traversed by large number of longitudinally and transversely running laticiferous tubes, wide phloem consisting of sieve tubes that are occasionally obliterated, parenchyma, companion cells, uni to triseriate medullary rays filled with starch grains and traversed throughout by a large number of laticiferous tubes⁴.

Chemical Constituents and Phytoconstituents:

The leaves of Thevetia neriifolia were examined, and C-nor-d-homocardenolide glycosides were obtained as in the preceding study, along with other common glycosides. α-l-Rhamnosides of digitoxigenin, cannogenin and thevetiogenin, and glycosides of uzarigenin were isolated from the leaves.⁵A new cardenolide, neriifoside, 3β-O-(α-l-acofriosy)-14β-hydroxy-5α-carda-20:22-enolide has been isolated from the fresh, uncrushed leaves of Thevetia neriifolia. The structures were determined by 1D and 2D NMR studies.⁶Five third-instar grubs of Henosepilachna vigintioctopunctata [Epilachna vigintioctopunctata], starved for 4 h, were fed with bittergourd [Momordica charantia] leaves of uniform age and size, which had been dipped in fresh or dried leaf extracts, or seed extracts, of Thevetia neriifolia [T. peruviana]. These extracts were obtained by crude or soxhlet extraction using acetone, benzene, ethanol, hexane, methanol or water as extractants. The comparative efficacy of the different plant parts, extractants and method of extraction was evaluated in terms of leaf protection and larval starvation. Seed extracts provided the highest mean leaf protection (61.73%) and larval starvation (72.27%) compared to both fresh and dried leaf extracts.⁷

Thevetia peruviana seeds cake were defatted and then treated with varying concentrations each of hydrochloric acid, sodium hydroxide and calcium hydroxide solutions. Each product of hydrolysis was extracted with chloroform to isolate aglycones. Various concentrations of hydrochloric acid and sodium hydroxide solution effected complete detoxification. Only 0.4 M and 0.5 M of calcium hydroxide solution detoxified the seeds completely. Albumin and globulin determination by biuret method confirmed that various concentrations of the hydrolyzing agents increased the quantity of extractable albumin and globulin in the cake. The study suggests that calcium hydroxide at high concentrations appear to be the best detoxicant⁸. The seed of the plant contains about 60% oil, which hydrolyses to give about 64.3% oleic acid, 6.3% linoleic, 17.1% palmitic, 11.8% stearic and 0.4% arachidonic acid. The defatted seed cake is about 30% protein but rich in toxins. The low alkyl esters have found wide applications as oleochemicals - as textile fibre lubricants, rolling oils and cutting oils. ⁹ The proximate fatty acid, amino acid and physicochemical properties of raw and processed. Thevitia peruviana were analyzed. The methods employed in processing are heat treatment and soaking. The seed contained crude protein, and the level of ether extract also varies from 687.4 g kg ^-1to 712.2 g kg ^-1. The two of the major cardiac glycosides were assigned to thevetin A and B on the basis of molecular mass and fragmentation¹⁰.

Fractionations of chloroform extract of the stem bark of Thevetia peruviana Juss.(Apocynaceae) led to the isolation of ursolic acid, acetyl ursolic acid, 6-keto acylic geranilane type monoterpene, oleanolic acid, and ellagic acid. Their structures were determined on the basis of spectroscopic methods such as IR, NMR and LCMS¹¹.

Morphological studies on leaves:

The histology of the xeromorphic leaves of Allamanda nerüfolia, Thevetia peruviana and Vinca minor have been examined by LM and SEM. A considerable variation occurs in characters not considered xeromorphic. The oxalate crystals in A. nerüfolia and T. peruviana differ conspicuously from each other both in shape and location. The nonarticulated laticifers are branched and located on both sides of the vascular strands in A. nerüfolia and T. peruviana, while they are unbranched and confined to the abaxial side of thehveins in V. minor. In addition attention was paid to the petiole appendages observed in the three species¹².

Traditional and Medicinal Uses:

The plant has been reported to have urethral discharges, worms, skin diseases, leucoderma, wounds, piles, eye troubles, itching, fevers, bronchitis, purgative activity¹³.

Activities:

Plant regenration and Somatic embryogenesis:

Cell suspension cultures, which retained embryogenic potential for almost 2 years, were established from young, expanding, juvenile leaves of a mature Thevetia peruviana L. tree. CaUi were obtained by culturing young leaf discs on MS medium supplemented with 2 mg/L 2, 4-dichlorophenoxyacetic acid (2, 4-D) and 0.1 mg/L kinetin. ¹⁴

Cell Suspension Cultures:

Cell suspension cultures of T. peruviana were established in four different culture media: Murashige–Skoog (MS), half Murashige – Skoog (half MS), Schenk–Hildebrandt (SH), and Gamborg (B5) to study their effect on cell growth. Cell growth kinetics were studied in SH medium, and the extracellular peruvoside production during the culture time was determined. The cell growth kinetics showed the four characteristic growth phases of a cell culture (lag, exponential, stationary, and death), and during none of these phases was it possible to observe peruvoside production. The current results are the first report of an in vitro peruvoside production system¹⁵.

Juvenomimetic Activity:

Ethanol extracts of fresh leaves and seeds of Thevetia neriifolia were tested for juvenomimetic action on red cotton bug, Dsydercus cingulatus, an important pest of cotton and okra. Conspicuous activity, based on larval mortality, duration of ovipositional period, emergence of malformed adults and reduced fecundity of the bugs, were noticed in 40% leaf and 10% seed extracts. Although moderate activity was seen in 20% leaf and 5% seed extracts, no significant effect was observed for the 10% leaf and 2.5% seed extract treatments¹⁶.

Pharmacological Activities and Clinical Trials:

HIV-I Reverse Transcriptase and HIV-I Integrase Inhibitory Activities:

Ethanol extract of Thevetia peruviana showed high anti HIV-1 (IC₁₀₀= 1.56 ug/ml) and HIV-1 integrase inhibitory activity (IC₅₀ = 12.0 ug/ml). Therefore, the ethanol extract of this plant was fractionated further into n-hexane, chloroform and water soluble fractions. The structure elucidation of new compounds from the water fraction and the inhibitory activities against HIV-1 Integrase and HIV-1 Reverse Transcriptase associated DNA polymerase [RNA-dependent DNA polymerase and DNA-dependent DNA polymerase] of the isolated compounds¹⁷.

Antimicrobial Activity:

The antimicrobial activity of ethanol extract obtained from Thevetia peruviana was tested against bacterial species of Escherichia coli ATCC 69314, Streptococcus lactis NCIM 50038, Enterobacter aerogenes NCIM 2340, Alcaligenes faecalis ATCC 15246, Pseudomonas aeruginosa NCIM 2200, Proteus vulgaris ATCC 6380 and fungal species of Fusarium oxysporum NCIM 1008, Alternaria helianthii ATCC 201540, Curvularia lunata ATCC 34477, Aspergillus niger NCIM 1207 and Penicillium spp NCIM 741. Better antimicrobial activity was observed with the extracts showed maximum activity against E. coli, Enterobacter aerogenes, Alcaligenes faecalis¹⁸.

Antifungal Activity:

Seeds of Thevetia peruviana were screened for their antifungal photoactivity. Extracts obtained either with n-hexane or dichloromethane were fractionated by column chromatography and further analysed by thin-layer chromatography. All seed extracts and fractions were tested for inhibition of the fungus Cladosporium cucumerinum for the evaluation of photoactive inhibitory effects. The most photoactive fraction was analysed by capillary gas chromatography with mass spectrometry in order to identify its constituents¹⁹.

Haematology, Growth and Tissue:

The effect of two inclusion levels of raw and processed. Thevetia peruviana seed cake as replacement for soyabean in the diets on growth, haematology and tissue pathology of 50 New Zealand x Chinchilla crossbred rabbits was studied²⁰.

Paper-Chromatographic Study²¹

A paper-chromatographic study has been made of the cardenolides from various parts of a yellow-flowered specimen of Thevetia peruviana (Pres.) K.Schum. The proportion of monoglycosides was low and acetylated monosides were present in traces only. The composition of the glycosides mixture from other parts of the plant were in general similar to that of the seed total extract. The glycosides extract from the seeds of an orange-flowered specimen was essentially the same as that from the yellow-flowered one.

Toxicological Studies:

A comparative study of the toxic effects of extracts from stem bark, leaf and seed kernel of yellow oleander (Thevetia peruviana) in albino rats was carried out. Male and female albino rats weighing 150-200 g were administered crude aqueous extracts of stem bark, leaf and seed kernel of the plant by intra-peritoneal injection or exposed to baits prepared with the dry extracts of the plant parts²². The Thevetia peruviana seed produces gastrointestinal and uterine toxicity in humans and urinary retention in experimental animals. This work was to identify the effects of ethyl acetate, methanol and aqueous extracts upon smooth muscle of bladder, uterus and intestine obtained from Wistar rats²³.

Side Effects:

Eating the leaves, flowers, or bark of common oleander may cause nausea, vomiting, stomach cramps, pain, fatigue, drowsiness, unsteadiness, bloody diarrhea, abnormal heart rhythms, seizures, liver or kidney damage, or unconsciousness.

Safety and Measure:

Peruvoside, a heart-active substance in yellow oleander kernels (similar to the drug digoxin), has been studied at 1.8 to 3.2 milligrams by mouth, as an initial dose, followed by an average daily dose of 0.6 milligrams per day for congestive heart failure. People with allergy/hypersensitivity to oleander or other cardiac glycosides such as digoxin or digitoxin may have reactions to oleander. Skin contact with sap from oleander leaves may cause rash²⁴.

CONCLUSION:

Major trust by whole of the pharmaceutical industry is focused towards design and development of new innovative/indigenous plant based drugs through investigation of leads from traditional system of medicine²⁵.In recent years, ethno-botanical and traditional uses of natural compounds, especially of plant origin received much attention as they are well tested for their efficacy and generally believed to be safe for human use. It is best classical approach in the search of new molecules for management of various diseases. Thorough screening of literature available on Thevetia peruviana depicted the fact that it is a popular remedy among the various ethnic groups, Ayurvedic and traditional practitioners for treatment of ailments. Various researchers have elaborated its important pharmacological actions viz antimicrobial, skin disorders, antipyretic, swelling, antifungal.

REFERENCES:

1. Thevetia peruviana. Available from: URL: http://en.wikipedia.org/wiki/Thevetia_peruviana

2. Balusamy T, Marappan R. Performance Evaluation of Direct Injection Diesel Engine with Blends of Thevetia peruviana Seed Oil and Diesel. Journal of Scientific and Industrial Research. 2007;66:1035-1040

3. Kareem SA, Kadiri AO . Hydrogenation of Thevetia peruviana Seed Oil using Cobalt Oxide- Molybdenum Oxide Catalyst Supported On Activated Carbon Nig. J. Pure and Appl. Science. 1998;13:629-635

4. Gupta AK, Tondon N, Sharma M .Quality standards of indian medicinal plants. New delhi: indian council of medicinal research;2005. p. 253-260. vol. II.

5. Abe F, Yamauchi T, Wan ASC. Cardiac glycosides from the leaves of Thevetia neriifolia. Phytochemistry. The International Journal of Plant Biochemistry. 1992;31(9):3189-3193

6. Siddiqui S, Siddiqui BS, Adil Q, Begum S. Cardenolides and triterpenoids of the leaves of Thevetia neriifolia. Phytochemistry. The International Journal of Plant Biochemistry. 1992;31(10):3541-3546

7. Bai H, Koshy G. Yellow oleander (Thevetia neriifolia Juss.) a bio-antifeedant for epilachna bettle (Henosepilachna Vigintioctopunctata L.). Journal of Tropical Agriculture. Available from : URL : http://www.cababstractsplus.org/ abstracts/Abstract.aspx?AcNo=20013025735

8. Usman AL, Ibiyemi SA, Oluwaniyi OO, Ameen MO. Effect of acid and alkaline hydrolysis on the concentrations of albumin and globulin in Thevetia peruviana seed cake protein extract. BIOKEMISTRI. 2003;15(1):16-21

9. Oluwaniyi OO, Ibiyemi SA. Efficacy of Catalysts in the Batch Esterification of the Fatty Acids of Thevetia peruviana Seed Oil. Journal of applied science and environment management. 2003;7(1):15-17

10. Olupona J, Macneil L, Macleod M, Atteh J. Nutritional Value of Thevetia peruviana Seed. Federal College of Animal Health and Production Technology, Nigeria.

11. Pavithra N, Padmaa MP. Phytoconstituents from stem bark of Thevetia neriifolia Juss. Pharmakine. 2009;I(IV):22-25

12. Fjell I. Anatomy of the xeromorphic leaves of Allamanda neriifolia, Thevetia neriifolia, and Vinca minor (Apocynaceae). Available from: URL: http://www3.interscience.wiley.com/journal/120040914/abstract?CRETRY=1andSRETRY=0

13. Kiritikar KR, Basu BD. Indian medicinal plants. Second ed. Dehradun: International book distributor; 1996. p. 1154-1156. vol. II.

14. Sharma A, Kumar A. Somatic embryogenesis and plant regenration from leaf-derived cell suspension of a mature tree – Thevetia peruviana L Plant Cell Reports. 1994;14:171-174

15. Zabala AM, Angarita M, Restrepo JM, Caicedo LA, Perea M. Elicitation with methyl-jasmonate stimulates peruvoside production in cell suspension cultures of Thevetia peruviana. In Vitro Cell.Dev.Biol.- Plant. 2009

16. Bai H, Koshy G. Juvenomimetic activity of extracts of Thevetia neriifolia Juss. To Dysdercus cingulatus F. (Hemiptera pyrrhocoreidae). Journal of tropical Agriculture. 2004;42(1-2):45-47

17. Tewtrakul S, Nakamura N, Hattori M, Fujiwara T, Supavita T. Flavanone and Flavonol Glycosides from the leaves of Thevetia peruviana And Their HIV-1 Reverse Transcriptase and HIV-1 Integrase Inhibitory Activities. Chem. Pharm Bull 2002;50(5):630-635

18. Patil RHS, Makari HK, Gurumurthy H. IN VITRO Antimicrobial Activity of Ethanol Extracts of Thevetia peruviana. Electronic Journal of Environmental, Agricultural and Food Chemistry. 2007;6(9):2318-2322

19. Goncalves GL, Nogueira JMF, Matos O, de Sousa RB. Photoactive extracts from Thevetia peruviana with antifungal properties against Cladosporium Cucumerinum. Journal of photochemistry and photobiology B:Biology. 2003;70(I):51-54

20. Taiwo VO, Afolabi OO, Adegbuyi OA. Effect of Thevetia peruviana Seed Cake Based Meal on the Growth, haematology and Tissue of Rabbits. Tropical and Subtropical Agroecosystems. 2004;4:7-14

21. Bisset NG. Apocynaceae: A Preliminary Paper-Chromatographic Study of the Glycosides from Thevetia peruviana (Pres.) K. Schum. Annales Bogorienses. 1961;IV(2):145-152

22. Oji O, Okafor QE . Toxicological studies on stem bark, leaf and seed kernel of yellow oleander (Thevetia peruviana) 1999; Available from: URL: http://www3.interscience.wiley.com/journal/70001439/abstract?CRETRY=1and SRETRY=0

23. Enriquez MEM, Guerrero MAG, Contreras AA, Sepúlveda CEA. Relexant and contractile effects of dry extracts from Thevetia peruviana (Tp) seed upon different smooth muscles of rat. Proc. West. Pharmacol. Soc. 2006;49:69-71

24. Oleander (Nerium oleander, Thevetia peruviana). Available from: URL: http://www.wellness.com/reference/herb/oleander-nerium-oleander-thevetia- peruviana/dosing-and-safety

25. Patwardhan B, Ashok DBV, Chorghade M. Ayurveda and natural products drug discovery. Current Science.2004;80(6):789-799

Received on 24.05.2010

Accepted on 12.06.2010

Research Journal of Pharmacognosy and Phytochemistry. 2(5): Sept.-Oct. 2010, 343-346