International Journal of Research and Engineering ISSN: 2348-7860 (O) | 2348-7852 (P) | Vol. 04 No. 12 | December 2017 | PP. 283-286 Digital Object Identifier DOI® http://dx.doi.org/10.21276/ijre.2017.4.12.2 Copyright © 2017 by authors and International Journal of Research and Engineering This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0 | | ORIGINAL ARTICLE Growth Inhibition of Various Pathogenic Microorganisms Using Effective Microorganisms (EM) Author(s): 1 *Safwat M. Safwat, 1 Ehab Rozaik Affiliation: 1 Sanitary & Environmental Engineering Division, Public Works Department, Faculty of Engineering, Cairo University, Egypt *Corresponding author: safwat@eng.cu.edu.eg Abstract: In recent years, researchers focus on treatment of wastewater using low-cost treatment processes. Several studies showed that using effective microorganisms (EM) is a promising technology in treatment of wastewater. However, the treatment mechanism using EM is not clear. In this study, the effect of EM towards several pathogenic microorganisms was investigated to examine its ability to inhibit their growth. The results showed that EM has the ability to inhibit the growth of pathogenic bacteria such as Escherichia coli, Pseudomonas Aeruginosa, and Streptococcus Faecalis; while no effect was detected on fungi that were examined. Keywords: Bacteria; Effective microorganisms; Fungi; Pathogens; Wastewater. I. INTRODUCTION Biological processes for wastewater treatment depend on using mixed communities of microorganisms, including bacteria, fungi, rotifers, and possibly algae. Domestic wastewater contains a wide variety of nonpathogenic and pathogenic bacteria. Among these pathogenic bacteria is the genus salmonella which can cause disease in humans and animals [1-2]. Fungi can be found in wastewater, but their presence is undesirable. Fungi are multicellular nonphotosynthetic plants and most of them are aerobic, but anaerobic species are known. Because of their different cellular composition, fungi tend to predominate over bacteria in wastes which are deficient in nitrogen or low in pH. They also have relatively large filamentous shape, so fungi tend to settle poorly and are thus difficult to remove by sedimentation [3]. Several studies showed that using effective microorganisms (EM) is a promising technology in treatment of wastewater [4-6]. EM is a liquid solution that was developed by Dr. Teruo Eliga, Professor of Horticulture at the University of the Ryukyus in Okinawa, Japan. Several studies showed the ability of EM to treat wastewater. Chemical oxygen demand, ammonia, phosphorus and other pollutants were reduced using EM [4,5]. A previous study by the authors showed the ability to remove salmonella from municipal wastewater when treated in anaerobic sequencing batch reactor seeded with activated EM [6]. However, to our knowledge, performance of EM towards pathogenic microorganisms has not been investigated yet. This study aims to show the effect of EM towards the growth of some pathogenic microorganisms. II. EXPERIMENTAL WORKS In the present study, a microbial analysis has been performed to investigate the effect of using EM towards some pathogenic microorganisms (bacteria and fungi). The species of microorganisms examined were: (a) Bacillus subtilis cells which are rod-shaped bacteria that are naturally found in soil and vegetation. [8] (b) Escherichia coli (E. coli) which are rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms [9, 10] (c) Neisseria gonorrhoeae which are species of coffee bean-shaped diplococci bacteria responsible for the sexually transmitted infection gonorrhea [11] (d) Pseudomonas aeruginosa which is noted for its environmental versatility, ability to cause disease, and its resistance to antibiotics [12] (e) Staphylococcus aureus which is a facultative anaerobic bacterium that is frequently found as part of the normal skin flora on the skin and nasal passages [13] (f) Streptococcus faecalis which is a spherical bacterium [14] (g) Aspergillus flavus which is a fungus that grows by producing thread like branching filaments known as hyphae [15] (h) Aspergillus niger which is a haploid filamentous fungi and responsible for producing extracellular enzymes and citric acid [16, 17] (i) Candida albicans which is a fungus that is normally present on the skin and in mucous membranes [18] (j) Candida parapsilosis which is an emerging major human pathogen and it is now one of the leading causes of invasive candidal disease [19].