_____________________________________________________________________________________________________ # Research scholar; *Corresponding author; Journal of Pharmaceutical Research International 33(63B): 485-490, 2021; Article no.JPRI.85114 ISSN: 2456-9119 (Past name: British Journal of Pharmaceutical Research, Past ISSN: 2231-2919, NLM ID: 101631759) Preliminary Phytochemical Screening and Antimicrobial Studies on the Aerial Parts Extracts of Crinum latifolium L. (Amaryllidaceae) Neeraj Kumar a*# , Manoj Kumar Mishra a and O.P. Agrawal a a Madhyanchal Professional University, Bhopal (M.P.), India. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/JPRI/2021/v33i63B36024 Open Peer Review History: This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here: https://www.sdiarticle5.com/review-history/85114 Received 25 October 2021 Accepted 28 December 2021 Published 29 December 2021 ABSTRACT The present study was undertaken to find the antimicrobial activities, phytochemical presence in various aerial parts extract of Crinum latifolium (C. latifolium). Qualitative analysis of various phytochemical constituents and quantitative analysis of total phenolics, flavonoids and alkaloids was determined by the well-known test protocol available in the literature. Quantitative analysis of phenolic, flavonoids and alkaloids was carried out by Folins Ciocalteau reagent, aluminium chloride and bromocresol green method respectively. The in vitro antimicrobial activity was done by well diffusion assay method against S. mutans and S. bongori using standard ofloxacin, ciprofloxacin (10-30μg/ml). The antimicrobial activity was determined by measuring the diameter of the zone of inhibition in term of millimeter (mm). The phytochemical analysis showed the presence of tannins, glycosides, flavonoids and alkaloids ect. The antimicrobial activity of hydroalcoholic extract of aerial parts against all microorganisms was concentration dependent manner but less than standard drug. It is concluded that the antimicrobial activity showed by the plant is due to the presence of these phytochemicals. For future studies, phytochemcials responsible for these activities can be isolated and modified for pharmacological purpose. Keywords: Infectious diseases; Crinum latifolium; antimicrobial activity; phytochemical analysis. Original Research Article