Vitex negundo Linn. : Phytoconstituents and Research Findings

 

R.V. Shete, K.V. Otari and O.G. Bichewar*

Department of Pharmacology, Rajgad Dnyanpeeth’s College of Pharmacy, Bhor, Pune

*Corresponding Author E-mail: ombichewar@gmail.com

 

ABSTRACT:

Vitex negundo (VN) Linn. commonly used herb in Ayurveda, Indian traditional system of medicine. As per ayurveda VN claimed to possess various medicinal uses. Many researchers reported effects of VN by using various experimental models. This review includes phytoconstituents and all updated reported activities of the plant. Up to present plant has reported for its antioxidant, anti-hyperglycemic, antibacterial, anti-inflammatory, analgesic, antifungal, antinociceptive, anticonvulsant, antioxidant, anti-tumor, hepatoprotective, gastroprotective, mosquito repellent, laxative, antiasthamatic, anxiolytic, anthelmentic, antiarthaitic, cardiotonic, effect on oxidative stress, pharmacokinetic interaction with paracetamol. Thus VN has great potential to be developed as drug by pharmaceutical industry. There is need of further investigation of VN as drug of choice for human beings.

 

KEYWORDS: Vitex negundo, Phytoconstituents, Traditional uses, Research findings.

 


INTRODUCTION:

Plants have a great potential for producing new drugs for human benefits. Plants used in traditional medicine contain a vast array of substances that can be used to treat chronic and even infectious diseases. The demand for more and more drugs from plant sources is continuously increasing. It is therefore essential for systematic evaluation of plants used in traditional medicine for various ailments. Hence, there is need to screen medicinal plants for promising biological activity1. In recent years there has been a phenomenal rise in the interest of scientific community to explore the pharmacological actions of herbs or to confirm the claims made about them in the official books of Ayurveda2.

 

VN belongs to family verbenaceae is one of the important herb claimed to be used in treatment of various diseases. VN is commonly known as Nirgudi (Marathi), five leaved chaste tree (English), Indrani (Sanskrit), and Nirgundi (Hindi)3,4. It is large, aromatic, shrub or a small, slender tree with an irregular trunk growing up to 4.5 m in height. Its stem and branches are covered with thin, grey bark, which becomes almost black and scaly when old. It occurs wild in most parts of India near moist places, ascending to an altitude of around 1500 m in the outer Himalayas.

 

Leaves are petiolate, opposite, 3-5 foliate, and leaflets are narrow lanceolate, mostly entire, glabrous above and pale whitish green and covered with a fine white tomentum beneath. Flowers are small, bluish purple, in peduncled cymes, group into large terminal, pyramidal panicles. Fruit is globose drupe, black when ripe, 5-6 mm in dia. Plants flower and fruit during March and August.

 

Phytoconstituents:

Leaves: VN leaves contains monoterpenoids iridoids (2-p-hydroxybenzoyl mussaenosidic, nishindaside, negundoside), triterpenoids  (betulinic acid, ursolic acid), flavonoids (gardenin A, gardenin B, corymbosin, vitexicarpin, 5 hydroxy-3,6,7,3,4-penta-metoxyflavone,3,5-dihydroxy-6,7,3,4-tetramethoxyflavanol) phenolic acid (p-hydroxybenzoic acid, 3,4-dihydroxybenzoic acid) leaves also contain essential oil like sabinene, 4-terpineol, β-caryophyllene and viridiflorol5.

 

Seed:  Diterpenes like negundoin A, negundoin B, negundoin C, negundoin D, negundoin E, negundoin F, negundoin G6, Benzoic and  palmitic acid7.

 

Root: It contains steroids like β-sitosterol, acetate, stimasterol, aliphatics (hentricontane) 5and several compounds like 2 beta, 3 alpha diacetoxyoleana-5, 12-dien-28-oic acid, 2 alpha, 3 alpha-dihydroxyoleana-5,12-dien-28-oic acid, 2 alpha, 3 beta-diacetoxy- 18-hydroxyoleana-5,12-dien-28-oic acid, vitexin and isovitexin8.

 

Bark: Flavone glycosides- 6- β-glucopyranosyl-7-hydroxy-3, 4, 5, tetramethoxyflavone-5-O-α-Lrhamnopyranoside,          3, 7-dihydroxy-4,6,8-trimethoxyflavone-5-O-(6"-O-acetyl-β- D-glucopyranoside), 3,3,4,6,7-pentamethoxyflavone-5-O-(4-O-β-D-glucopyranosyl)-α-L-rhamnopyranoside, 4,5,7-trihydroxyflavone-8-(2-caffeoyl-β-D-glucopyranoside), galactopyranoside, leucoanthocyanidines, leucodelphindin methyl ether, leucocyanidin-7-O-rhamnoglucoside, luteolin, acerosin, terpenes, sterols, phenolic compounds, alkaloids, organic acid, β- sitosterol, glucosides, anthocyanines, and p-hydroxybenzoic acid.

 

Flower: Flowers oil contains a-selinene, germacren-4-ol, carryophylene epoxide, (E)-nerolidol, p-cymene,and valencene9.

 

Traditional uses: Analgesic, in arthritic pain, in cervical pain, relief of headache antibacterial, cleaning and healing of wounds, anthelmentic, in fungal infection of ear, hair tonic, brain tonic, improve memory, diuretic, in loss of appetite, anorexia, expectorant, febrifuge, anti-inflammatory, in conjunctivitis, in synovitis, in colitis, pharyngitis, stomatitis, in dysmenorrhoea, in uticaria, in cough, in skin diseases, in ward of malaria4,5.

 

Research findings on Vitex negundo Linn.

·       Acute toxicity study:  Acute toxicity study of ethanolic leaf extract of VN in albino rats was studied by oral route indicated it is practically nontoxic, its LD50 dose recorded was 7.58g/kg of body weight9.

 

·       Hepatoprotective activity: VN leaf ethanolic extract was investigated against hepatotoxicity produced by administering a combination of three anti-tubercular drugs isoniazide 7.5 mg/kg, rifampin 10 mg/kg and pyrazinamide 35 mg/kg for 35 days by oral route in rats. Vitex negundo leaf ethanolic extract was administered in three graded doses of 100, 250 and 500 mg/kg orally, 45 min prior to anti-tubercular challenge for 35 days. Hepatoprotective effect of Vitex negundo leaf ethanolic extract was evident in the doses of 250 and 500 mg/kg. Histology of the liver section of the animals treated with the VN leaf ethanolic extract in the doses of 250 and 500 mg/kg further confirms the activity10.

 

·       Gastroprotective activity: Aqueous extract of VN against the gastric mucosal damage induced by aspirin was studied in albino rats. Aspirin was administered intraperitoneally at a dose of 80mg/kg body weight to induce ulcer and the resultant elevated levels of lipid peroxide was taken as an index of oxidative stress. The gastroprotective effect of VN was observed at an oral dose of 200mg/kg body weight administered for 18 days before ulcer induction. The effect of VN on the levels of RBC, WBC, and Proteins, carbohydrates, lipid peroxides, super oxide dismutase and glutathione were investigated in ulcer induced rats and the results revealed that VN has a pivotal role in treating ulcer11.

 

·       Mosquito repellent activity Oil obtained from stream distillate of Vitex negundo leaves was fractionated by column chromatography. Mosquito repellence activity, as evaluated against Aedes aegypti was mainly confined to the most polar fractions. The protection period against mosquito bites by polar fractions ranged between 1-3 h. However, the mean protection period values of these fractions did not show significant increase in the subsequent subfractions12.

 

·       Laxative Activity Crude aqueous extract of VN leaves at doses 100 and 200 mg/kg was investigated for laxative activity in albino rats that were compared with standard drug agar-agar (300mg/kg, p.o.) in normal saline. The rats were fasted for 12 hours before the experiment. After 8 hours of drug administration the faeces were collected and weighed. The extract was found to produce significant laxative activity in dose dependant manner. The activity may be contributed to the phytoconstituents present13.

 

·       Antihyperglycemic activity: Validation of the ethnobotanical use of the leaves of VN as antidiabetic agents using the oral glucose tolerance test. In this test leaves of VN exhibited antihyperglycemic activities when fed simultaneously with glucose VN exhibited greater anti-hyperglycemic activity VN showed a significant decrease in blood glucose level at 60 min14.

 

·       Anthelmentic activity: Ethanolic extract of VN was investigated for anthelmintic activity against Indian earthworm Pheritima posthuma. Various concentrations of extract were tested and results were expressed in terms of time for paralysis and time for death of worms. Piperazine citrate (10 mg/ml) was used as a reference standard and distilled water as a control group. Dose dependent activity was observed in plant extract of VN15.

 

·       Antiasthmatic activity: The antiasthmatic activity of Ethanolic, petroleum ether, aqueous and ethyl acetate fractions of VN leaves was evaluated by various experimental models like mast cell degranulation by compound 48/80, passive cutaneous anaphylaxis and egg-albumin induced asthma. Dexamethasone (5mg/kg) was used as a reference standard various fractions significant protection of rat mesenteric mast cells from disruption caused by compound 48/80. Animals treated with these fractions showed significantly lesser the amount of eosinophils, serum bicarbonate level and lung body weight ratio and significantly higher tidal volume as compared to untreated, egg-albumin sensitized animals16.

 

·       Antimicrobial Activity Ethanolic extract was subjected to preliminary screening for antimicrobial activity. Antimicrobial activity was determined by the Disc Diffusion method ethanolic extracts exhibited significant anti-microbial activity comparable to the standard drug tetracycline17.

 

In another study bioactivity guided phytochemical investigation of methanolic extract of leaves of VN resulted in the isolation of eight compounds under silicagel VLC, CC and preparative TLC. They were found to have significant antibiotic activity against Bacillus subtilis, Staphylococcus aureus, Micrococcus pyogenes, Pseudomonas aeruginosa and E. coli. The compounds vitegnoside, and 7, 8 dimethyl herbacetin 3-rhamnoside have MIC 6.25mg/ml18.

 

·       Antimicrofilarial activity: Methanolic extracts of roots and leaves of VN was explored for possible antifilarial effect against Brugia malayi microfilariae. It was observed that among the herbal extracts, root extract of VN at 100 ng/ml concentrations showed complete loss of motility of microfilariae after 48 hr of incubation. Thin layer chromatography of the extracts revealed the presence of alkaloids, saponin and flavonoids in the roots and leaves of VN19.

 

·       Antinociceptive activity: Antinociceptive activity of ethanolic leaf extract of Vitex-negundo (100, 250 and 500 mg/kg, p.o) was investigated by using Tail flick test in rats and acetic acid induced writhing in mice. The effect was compared with meperidine (40 mg/kg, sc) in tail flick method and aspirin (50 mg/kg, p.o) in writhing test as a standard control respectively. An interaction with naloxone hydrochloride was also studied in tail flick method for its mechanism of central analgesic action. The test drug showed significant analgesic activity in dose dependant manner in both the experimental models.  Observations suggest that VN possesses both central and peripheral analgesic activity20.

 

·       Cadiotonic activity: The cardiotonic effect of aqueous extract of leaves of VN was studied by using isolated frog heart perfusion technique. Ringer solution without calcium was used as a vehicle for administration of aqueous extract as test and digoxin as standard. A significant increase in the height of force of contraction (positive ionotropic effect) and decrease in heart rate (negative chronotropic effect) was observed at smaller doses. The effect increased as dose was increased21.

 

·       Antifungal activity: The ethanolic extract was leaves of VN investigated by bioactivity guided fractionation resulted in the isolation of new flavone glycoside as compound 4 along with five known compounds 1–3, 5 and 6. The new flavone glycoside 4 and compound 5 were found to have significant antifungal activity against Trichophyton mentagrophytes and Cryptococcus neoformans at MIC 6.25 g/ml22.

 

In another study In vitro antifungal activity of fruits of VN was examined against 5 common fungal strains, Candida albicans, Candida glabrata, Aspergillus flavus, Microsporum canis and Fusarium solani. Ethanol extract of fruit seeds showed significant activity against Fusarium solani and moderate response against Microsporum canis with no effect on Candida albican23.

 

·       Anticonvulsant activity: The ethanolic leaf extract of VN was administered orally in graded doses (250, 500 and 1000 mg/kg p.o) in both the experimental models and the effects were compared with diphenylhydantoin in maximal electroshock seizures method and valporic acid in pentylenetetarazole induced seizures method as standard control respectively. The Vitex-negundo in the doses (250, 500 and 1000 mg/kg, p.o) did not show protection against maximal electroshock seizures to any significant extent but significant post-ictal depression was observed in the dose of 1000 mg/kg body weight in comparison to control. However, sub-protective dose of test drug (100 mg/ kg, p.o) potentiated the anticonvulsant action of diphenylhydantoin. The test drug in the dose (1000 mg/kg, po) showed 50% protection in clonic seizures and 24-hour mortality against pentylenetetarazole induced seizures. Vitex-negundo potentiated anticonvulsant activity of valporic acid24.

 

·       Anxiolytic activity: Ethanolic extract prepared from the roots of VN was evaluated by using the elevated plus maze and light dark exploration test in mice. male mice were either treated orally with the extract or the positive control diazepam, respectively, 1 hour before behavioral evaluation. Oral administration of 100 and 200 mg/kg of VN extract significantly increased the percentage time spent on and the number of entries into the open arms of the elevated pulse maze. The effect was comparable to that of the benzodiazepine diazepam25.

 

·       Anticancer activity: The anticancer activity of the ethanolic extract of leaves of Vitex negundo was evaluated against Dalton’s ascitic lymphoma (DAL) in Swiss albino mice at the dose of 250 and 500 mg/kg, body weight. The experimental parameters used were tumour volume, tumour cell count, viable tumour cell count, mean survival time and increase in life span to assess antitumour activity. The extract administered orally for 14 consecutive days to tumor bearing group of animals. The extract increase the life span of DAL treated mice and restore the hematological parameters as compared with the DAL bearing mice in dose dependant manner. The study revealed that the EVN showed significant antitumour activity in tested animal models. The EVN was found to be cytotoxic to mouse lung fibroblast (L-929) cells in long term chemosensitive cytotoxic assay26.

 

·       Anti-inflammatory and analgesic activity: The analgesic activity of Vitex negundo leaf hydroalcoholic extract [500 and 1000 mg/kg] was studied using acetic acid induced writhing test in mice for assessing peripheral analgesic effect and tail immersion test in mice for assessing central analgesic effect. The antiinflammatory activity of extract (500 and 1000 mg/kg) was studied by using the models of carrageenin-induced rat paw oedema and carrageenin induced granuloma pouch in rats for assessing the effect on acute and subacute inflammations, respectively. Isolated rat uterus was used to study the involvement of prostaglandins in the analgesic and antiinflammatory activities of extract. The chemical analysis of the extract was done using HPTLC technique Vitex negundo extract may have both central and peripheral analgesic action extract also possesses antiinflammatory activity which was more pronounced on subacute rather than on acute inflammation. The analgesic and anti- inflammatory action of extract can be attributed to its flavonoids content, which are known to act through inhibition of prostaglandin biosynthesis27.

 

·       An adjuvant to standard anti-inflammatory drugs: Study was undertaken to investigate interaction of ethanolic leaf extract of VN Linn with standard anti-inflammatory drugs in sub-effective doses per orally to evaluate its potential role as an adjuvant therapy. Carrageenin induced hind paw oedema and cotton pellet granuloma test in albino rats were employed to study interaction of Vitex negundo leaf extract with standard antiinflammatory drugs in sub-effective doses per orally to evaluate its potential role as an adjuvant therapy. The sub-effective dose of VN potentiated anti-inflammatory activity of phenlbutazone and ibuprofen significantly in carrageenin induced hind paw oedema and cotton pellet granuloma models. The potentiation of anti-inflammatory activities phenlbutazone and ibuprofen by VN indicates that it may be useful as an adjuvant therapy along with standard anti-inflammatory drugs28.

 

·       Antioxidant activity Antioxidant potency of VN was investigated by employing various established in vitro systems, such as 2,20-azino-bis 3-ethyl benzothiazoline- 6-sulfuric acid /Lipid Peroxides/Superoxide/Hydroxyl radical scavenging and iron ion chelation. Total antioxidant capacity was determined by the assay based on the preformed radical monocation 2,-20-azino-bis 3-ethyl benzothiazoline- 6-sulfuric acid. Lipid peroxidation was assessed in terms of thiobarbituric acid reactive substances by using egg yolk homogenates as lipid rich media. Superoxide radical scavenging assay was based on the riboflavin-light-Nitro blue tetrazolium system. Hydroxyl radical trapping potential was determined by evaluating hydroxyl radical induced deoxyribose degradation using the thiobarbituric acid method. In order to assess the metal chelation properties, hydroxyl radical induced deoxyribose degradation was evaluated in the absence of Ethylenediamine tetra acetic acid. It was concluded that the polar fractions of VN possess potent antioxidant properties, which may be mediated through direct trapping of the free radicals and also through metal chelation29.

 

·       Effect on oxidative stress: Hydroalcoholic extract of VN on oxidative stress was studied in albino rats. Oxidative stress parameters like measure of malondialdehyde level in form of thiobarbituric acid species level and superoxide dismutase level were investigated. Ethanol was used to induce oxidative stress. The study suggests that VN leaf extract can produce reduction of oxidative stress by reducing lipid peroxidation whereas it has failed to modulate endogenous antioxidant enzyme activity30.

 

·       Pharmacokinetic-interaction of Vitex negundo Linn and paracetamol:  Interaction between orally-administered ethanolic extract of leaves of Vitex negundo and paracetamol was investigated in albino rats. Solvent free dried extract of VN leaves was orally given to experimental rats in different doses (62.5-1000 mg/kg/b.wt.), daily for six consecutive days. On days 3 and 6, paracetamol (100 mg/kg/b.wt.) was orally administered to these extract treated rats and control rats (drug vector) at various time intervals (5 min - 120 min), blood was collected from each animal and paracetamol concentration was determined in plasma by using HPLC with UV detector at 249 nm. Various pharmacokinetic parameters were calculated by non compartmental model. A significant decline in plasma concentration of paracetamol with time-gap was recorded with the increasing dose of VN extract31-32.

 

CONCLUSION:

VN belongs to family verbenaceae is one of the important herb mentioned in Auyrveda for its beneficial effect in human diseases. According to Ayurveda this herb contain various chemical constituents may be responsible for its beneficial effect. Many researchers attempted to find various effects by using experimental models, thus Vitex negundo have ability to its use in various diseases but there is further need to study which chemical constituents responsible for various pharmacological effects.

 

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Received on 15.06.2010       Modified on 29.06.2010

Accepted on 08.07.2010      © RJPT All right reserved

Research J. Pharm. and Tech. 4 (1): January 2011; Page 47-51