Vol 10, Issue 8, 2017 Online - 2455-3891 Print - 0974-2441 PHYTOCHEMICAL AND PHARMACOLOGICAL EVALUATION OF CALLISTEMON CITRINUS FOR ANTIDEPRESSANT ACTIVITY IN ALBINO MICE VIJETHA PENDYALA 1 , SANTHRANI THAAKUR 2 * 1 Department of Pharmacognosy, Chebrolu Hanumaiah Institute of Pharmaceutical Sciences, Guntur, Andhra Pradesh, India. 2 Departmet of Pharmacology, Institute of Pharmaceutical Technology, Sri Padmavathi Mahila Viswavidyalayam, Tirupati, Andhra Pradesh, India. Email: drsanthrani@gmail.com Received: 07 April 2017, Revised and Accepted: 05 May 2017 ABSTRACT Objective: The present study was carried out to find out the antidepressant activity of different fractions of stems and leaves of Callistemon citrinus (CC). The efficacy of the fractions was compared with the standard reference drug imipramine. Methods: All the studies were conducted according to the ethical guidelines of CPCSEA. Healthy adult albino mice weighing 20-30 g were used as experimental animals. The leaves of CC were extracted with alcohol and fractionated with chloroform and petroleum ether. All the fractions were subjected for preliminary phytochemical screening, using various qualitative tests. In the present investigation, tail suspension test (TST) and forced swim test (FST) are selected as animal models for evaluation of antidepressant activity in albino mice. Results: The preliminary phytochemical screening of CC has revealed the presence of carbohydrates, tannins, and flavonoids in a hydroalcoholic fraction. Chloroform fraction showed positive results toward flavonoids, alkaloids, tannins, glycosides, and steroids. Alcoholic and chloroform extract (100 and 200 mg/kg p.o.) of CC administered orally for 14 successive days had decreased the immobility periods significantly in a dose-dependent manner in both TST and FST, showing significant antidepressant-like activity. The activities of the extracts were found to be comparable to imipramine in both FST and TST. Conclusions: Although a number of synthetic drugs are being used as a standard treatment for clinically depressed patient, they have adverse effects that can compromise the therapeutic treatment. In the traditional systems of medicine, many plants and formulations have been used to treat depression for thousands of years. The results of the study indicate that CC can be used as an antidepressant herb. Keywords: Callistemon citrinus, Antidepressant activity, Forced swim test, Tail suspension test, Depression. INTRODUCTION Depression is a psychiatric disorder, which affects 21% of the world population and is considered as disorders of mood rather than disturbances of thought or cognition. It is a chronic illness associated with low mood and a range of associated emotional, cognitive, physical, and behavioral symptoms [1]. There are two types of depression; the first one is unipolar depression, in which the mood swings are always in the same direction and caused due to stressful events of life. The second one is bipolar depression, also termed as endogenous depression, in which the mood swings are bidirectional and unrelated to external stress [2]. Although there are numerous synthetic drugs available for the treatment of depression, they are associated with various adverse effects and drug–drug interactions that can compromise the treatment [3]. Therefore, this aim was to search for antidepressants from plants and explore their potential in the treatment of depression. The genus Callistemon is known for its anti-cough, anti-bronchitis, and insecticidal properties. Callistemon citrinus (CC) (Family: Myrtaceae) commonly known as bottlebrush tree grows in Australia and cultivated throughout India, Malaysia, and tropical countries. CC has been claimed in traditional literature to be valuable against a wide variety of diseases [4,5]. The plant has been used by tribal communities for the treatment of gastrointestinal disorders, and the leaves are used for their anthelmintic, anti-inflammatory, antipyretic, and antitussive properties. The phytoconstituents reported from CC are flavonoids: Pelargonidin- 3,5-diglucoside, cyanidin-3,5-diglucoside, and kaempferol; monoterpenoids: β-pinene and 1,8-cineole; tannins: Pyrogallol and catechol; triterpenoids: Betulinic acid, α-amyrin and oleanolic acid, and β-sitosterol in flowers and fruits [6,7]. The leaves contain flavonoids: 3’4’7-trihydroxy flavonol, 3’4’7-trihydroxy flavone, 3’4’7-trihydroxy flavonol-3-glucoside, 3’4’7-trihydroxy flavone-7- galactoside, 5,7-dihydroxy-3,8,4’-trimethoxy-6-C-methylflavone, kaempferol-3-O-β-D-galactopyranoside, and quercetin-3-O-(2’’- O-galloyl)-β-D-glucopyranoside [8,9]. The leaves are reported to contain monoterpenoids: 1,8-cineole, α-pinene, and limonene and triterpenoids: α-lupeol, 2α-hydroxy uvaol, 2α-hydroxy ursolic acid, ursolic acid, oleanolic acid, and phloroglucinol derivative [10,11]. The pharmacological activities reported for CC are antiasthmatic, antimicrobial, calcium channel blocker, cytotoxicity, and anthelmintic effects [12]. The literature review reveals that no study was done on the antidepressant property of this plant scientifically. Therefore, this study focused on evaluation of antidepressant potential of CC in mice. MATERIALS AND METHODS Collection of plant material and extraction The aerial parts of CC were collected at NH-5 near Guntur. The plant was authentified by the Department of Botany, Acharya Nagarjuna University, Guntur, and voucher specimen was preserved. The leaves and stems were separated, dried, powdered, and then extracted with alcohol as solvent using soxhelation for 4 cycles. Then, the extracted drug was further evaporated using simple distillation apparatus to obtain the concentrate. To this extract, aliquots of water were added and then fractionated successively using petroleum ether and chloroform © 2017 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4. 0/) DOI: http://dx.doi.org/10.22159/ajpcr.2017.v10i8.18998 Research Article