www.iajpr.com Page3954 Indo American Journal of Pharmaceutical Research, 2016 ISSN NO: 2231-6876 INVESTIGATION OF CNS DEPRESSANT, ANTI-DIARRHEAL AND CYTOTOXIC ACTIVITIES OF CRUDE METHANOLIC EXTRACTS OF ACACIA NILOTICA AND JUSTICIA ADHATODA ROOT Fahad Hussain, Saikat Kumar Poddar, Amlan Ganguly, S.M. Abdur Rahman Department of Clinical Pharmacy & Pharmacology, Faculty of Pharmacy, University of Dhaka. Corresponding author S.M. Abdur Rahman, Ph.D Professor, Department of Clinical Pharmacy & Pharmacology, Faculty of Pharmacy, University of Dhaka. rahman_du@yahoo.com Copy right © 2016 This is an Open Access article distributed under the terms of the Indo American journal of Pharmaceutical Research, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. ARTICLE INFO ABSTRACT Article history Received 07/12/2015 Available online 31/01/2016 Keywords Acacia Nilotica, Justicia Adhatoda, CNS Depressant, Anti-Diarrheal, Brine Shrimp Cytotoxicity, Swiss-Albino Mice. A long tradition of indigenous herbal medicinal systems, based on rich local plant diversity, is considered as an important component of primary health care system in Bangladesh. The main purpose of this study is screening of methanolic extracts of Acacia nilotica and Justicia adhatoda roots for possible CNS depressant, Anti-diarrheal and Cytotoxic activities in experimental swiss albino mice. After collection, plants were dried, powdered and extracted by methanol, followed by n-hexane, ethyl acetate, and chloroform fraction for getting the sample root extracts. Swiss-albino mice were used for CNS depressant, Anti-diarrheal effect assay whereas Artemia salina leach was for the cytotoxic activity screening. Sodium- phenobarbitone induced sleeping time, castor oil induced diarrhea and brine shrimp lethality bioassay were followed for CNS depressant, Anti-diarrheal and cytotoxic activity assay. Dunnett t-test analysis was done by SPSS version 19 on windows. The methanolic extract of A. nilotica root at the doses of 200 mg/kg and 400 mg/kg body weight showed highly significant (P<0.001) CNS depressant activity. In case of anti-diarrheal activity assay, A. nilotica at the dose of 400 mg/kg showed 41.37% inhibition of defecation which is comparable to the value obtained by standard Loperamide (58.62%). In cytotoxicity testing, methanolic extract of J. adhatoda root showed mild cytotoxicity (LC 50 58.61μg/ml) while for the A. nilotica, it appeared as 42.55 μg/ml compared to the value obtained by standard Vincristine Sulfate (0.544 μg/ml).These current findings confirm that the methanolic extracts of A. nilotica and J. adhatoda root exhibited prominent CNS depressant, anti-diarrheal potential and less cytoxicity. Please cite this article in press as Fahad Hussain et al. Investigation of CNS depressant, Anti-diarrheal and Cytotoxic activities of crude methanolic extracts of Acacia nilotica and Justicia adhatoda root. Indo American Journal of Pharmaceutical Research.2016:6(01).