GSC Biological and Pharmaceutical Sciences, 2020, 12(01), 249-254 Available online at GSC Online Press Directory GSC Biological and Pharmaceutical Sciences e-ISSN: 2581-3250, CODEN (USA): GBPSC2 Journal homepage: https://www.gsconlinepress.com/journals/gscbps  Corresponding author: Ajaegbu Eze Elijah Copyright © 2020 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0. (R ESEARCH A RTICLE ) Antimicrobial screening of the crude extract of Hannoa klaineana against some pathogens Ibe Chioma Ifeoma 1 , Ajaegbu Eze Elijah 2, * , Ikuesan Adeniran John 2 , Dieke Adaobi Janefrances 2 and Ezugwu Obidike Christopher 3 1 Department of Pharmacognosy and Traditional Medicine, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria. 2 Department of Applied Sciences, Faculty of Applied Sciences and General Studies, Federal College of Dental Technology and Therapy, Trans-Ekulu, Enugu State, Nigeria. 3 Department of Pharmacognosy and Environmental Medicine, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, Enugu State, Nigeria. Publication history: Received on 20 July 2020; revised on 29 July 2020; accepted on 30 July 2020 Article DOI: https://doi.org/10.30574/gscbps.2020.12.1.0233 Abstract Hannoa klaineana is an ever green plant belonging to the Simaroubaceae family commonly known as Oghuru in Igbo, itekiri in Edo and igi gun in Yoruba. It has been used in ethnomedicine for the treatment of malaria, cough, and stomach problems. The present study assessed the antimicrobial property of the extract of H. klaineana against Staphylococcus aureus, Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Bacilus substilus, and Candida albicans using the agar diffusion method. Our preliminary phytochemical studies showed the presence of resins, steroids, terpenoids, glycosides, alkaloids, flavonoids, tannins, saponins, and phenols. Quantitative determination of the phytochemicals present revealed alkaloids (1.2%), tannins (11.2%), flavonoids (3%), saponins (29.3%), and phenolic compounds (45.7%). The extract of H. klaineana showed good antimicrobial activity against C. albicans and moderate active against S. aureus, S. typhi, E. coli, P. aeruginosa, B. substilus. These results further confirm the potentials of Nigerian plants as a source of bioactive compounds with pharmaceutical, agricultural or industrial applications. Keywords: Antimicrobial; Phytochemical; Bacteria; Fungi; Hannoa klaineana. 1. Introduction Medicinal plants are described by the World Health Organization (WHO) as plants that hold within compounds that can be utilized for therapeutic purposes or can be combined to create very able drugs [1]. Natural products are compounds created by microorganisms e.g. bacteria, fungi, etc., and plants to respond to changes. They are greatly utilized in industries e.g. pharmaceuticals, etc., for a range of pharmacological activities and striking structural diversity [2]. The rise in the population of the world, disease, health problems, etc. is of great concern. These have led to the use of these chemical molecules or compounds from these plants as pharmaceutical agents. Phytochemicals are bioactive compounds found in plant diets such as fruits, vegetables, grains, beans that are responsible for disease protection [3]. Hannoa klaineana has been used several in ethnomedicine to treat cough, malaria, stomach problems. Some studies have proven its antimicrobial, anti-inflammatory, antiviral activity, anti feedant, and anti-tumor activities. It is the most known in Nigeria, among the other species of Simaroubaceae [4]. It is used in other African countries to take care of fevers, malaria, cough, colic diseases, and antitumor activity [5]. The general objective