INTRODUCTION Aspergillus flavus is saprophytic fungi and common contaminants of agricultural products. It gets entry into crops in pre-harvest, post-harvesting and during harvesting period. Under favorable growth conditions, A. flavus produce toxic secondary metabolites called aflatoxins (Carry et al., 2018). Four major naturally occurring aflatoxins are AFB1, AFB2, AFG1, and AFG2. However, other important aflatoxins are AFM1 and AFM2 secreted in milk and meat of animals (Kumar, 2018). Aflatoxins are major safety concern in food industry because these suppress immune system and predispose to diseases, affect different organs (liver, kidneys and brain) and molecules (Protein and DNA) of living body (Wu et al., 2016). Fungal species are also source of industrially important enzymes that hydrolyze carbohydrates, protein and lipids (Kumari et al., 2017). Aspergillus is a well-known genus for amylases production and has higher production potential among fungi (Souza and Magalhaes, 2010; Champreda et al., 2007). Aspergillus niger is the most important specie capable of producing amylases so far. Aspergillus flavus is also a good amylase producer (Shafique et al., 2010). Microbial (bacteria and fungi) sources of amylases are preferred over other sources (plants and animals) on industrial level because of their cost effectiveness, better quality of amylases and easy manipulation of microorganisms (Shafique et al., 2010; Bhanwar et al., 2014). Amylases are amylolytic enzymes (Abe et al., 2015). Amylases (α-Amylase E.C.3.2.1.1, β-Amylase EC 3.2.1.2 and γ-Amylase EC 3.2.1.3) have wide spectrum of applications in various industries including paper, textile and pharmaceutical industry (Mehta and Satyanarayana, 2016). Amylases are also utilized in fermentation, brewing, detergents, baking (Silva et al., 2013) and distilling industry (Khalid-Bin-Ferdaus et al., 2018). Amylases application in food industry ranges from clearing fruit juices, starch syrups preparation, making cakes, bread making (dough preparation and anti-stalling agent), to sweetening agent (conversion of glucose to fructose (Singh et al., 2014; Mehta and Satyanarayana, 2016). Amylases are being used as feed supplement to improve the digestibility of starch based diets in birds (Onderci et al., 2006). Amylases production potential of non-mycotoxin producing indigenous A. flavus soil isolates was determined and optimized under different physical and nutritional parameters. The non-toxigenic amylase producing A. flavus may be better candidate for amylases to be used on industrial level. MATERIALS AND METHODS Collection of soil samples: Soil samples having animal rations (n=145) were randomly collected from livestock farms of 29 villages (one sample from each farm, selected 5 Pak. J. Agri. Sci., Vol. 56(3), 747-752; 2019 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI:10.21162/PAKJAS/19.6121 http://www.pakjas.com.pk ENZYMATIC AND AFLATOXIN PRODUCTION POTENTIAL OF ASPERGILLUS FLAVUS Saba Sana 1 , Aftab Ahmad Anjum 1,* , Tahir Yaqub 1 , Muhammad Nasir 2 and Ali Ahmad 3 1 Department of Microbiology, University of Veterinary and Animal Sciences, Lahore Pakistan; 2 Department of Nutrition, University of Veterinary and Animal Sciences, Lahore Pakistan; 3 Experimental Research Lab, University of Health Sciences Lahore Pakistan. * Corresponding author’s e-mail: aftab.anjum@uvas.edu.pk Fungi especially Aspergillus species are potential candidates for production of mycotoxins and industrially important enzymes. Aspergillus flavus isolates (129) recovered from soil mixed with animal rations (n=145) had aflatoxins (17.82%) and Enzymes (10.37%) production potential. Quantity of detected Aflatoxins varied for different isolates i.e., 3.25 to 11622.24ng, 21.34 to 194.47ng and 3.36 to 40.12ng per mL of Sabouraud’s dextrose broth in case of AFB1, AFB2 and AFG1 as determined by High performance liquid chromatography. Optimization of non-toxigenic starch hydrolyzing A. flavus was carried out at different incubation temperatures (22, 30 and 37°C), pH (4.5, 6 and 7.5) and substrates including maize, wheat bran and rice husk (1, 3 and 5% each) for incubation period of 7 days. In optimization experiments for starch hydrolysis, most of the A. flavus (86%) produced highest enzyme (IU) at 37°C and pH 6 quantified by Dinitrosalicylic method. Most of the isolates were able to produce enzymes using rice husk followed by maize. The highest quantity of enzyme was produced by A. flavus (179.88+1.71IU) using one percent of maize at pH 6 and 37°C. It was concluded that indigenous non-toxigenic A. flavus can be used in food industry as biological source of starch hydrolyzing enzymes. Keywords: Aspergillus flavus, starch hydrolysis, food industry, aflatoxins, substrates