Research Article Optimization of Extraction Parameters for Enhanced Production of Ovotransferrin from Egg White for Antimicrobial Applications Eyad M. A. Alshammari, 1 Saif Khan, 1 Arshad Jawed, 2 Mohd Adnan, 1 Mahvish Khan, 1 Gowher Nabi, 3 Mohtashim Lohani, 4 and Shafiul Haque 2,5 1 Department of Clinical Nutrition, College of Applied Medical Sciences, University of Ha’il, Ha’il 2440, Saudi Arabia 2 Research and Scientifc Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan 45142, Saudi Arabia 3 Department of Genetics, College of Applied Medical Sciences, Jazan University, Jazan 45142, Saudi Arabia 4 Department of Biosciences, Integral University, Lucknow, Uttar Pradesh 226026, India 5 Department of Biosciences, Jamia Millia Islamia, New Delhi 110025, India Correspondence should be addressed to Shaful Haque; shaful.haque@hotmail.com Received 2 September 2015; Accepted 20 October 2015 Academic Editor: Pengjun Shi Copyright © 2015 Eyad M. A. Alshammari et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Ovotransferrin is the second most abundant protein (∼12-13% of the total egg protein) in egg white afer ovalbumin. Ovotransferrin is a potent natural antimicrobial agent as it possesses antibacterial, antifungal, and antiviral properties and is also the major metal binding protein found in egg, which makes it an industrially important protein. Ovotransferrin was extracted from egg white using its metal (iron) binding properties. In the present study, eggs from two diferent sources were used (fresh local eggs from domestic household source and poultry eggs from shops) to compare the results and Response Surface Methodology was used for the experiment design and data analysis. Te following extraction conditions were optimized so as to maximize the yield of ovotransferrin from egg white: ethanol % (v/v) and pH and volume (mL) of 25 mM FeCl 3 /50 mL of egg white. A maximum yield of ∼85 ± 2.5% was obtained near the optimum extraction conditions. Te yield was calculated based on the theoretical value (934 mg) of ovotransferrin in 100 mL of 1.5x diluted egg white solution. Our results suggest that efcient downstream processing may reduce the cost of overall production process of this promising enzyme, making it a natural and cost-efective alternative to the existing chemically synthesized antimicrobial agents. 1. Introduction Transferrins are iron binding proteins that control the level of free iron in biological fuids, especially in the blood plasma [1]. Transferrins can be divided into 4 categories according to their occurrence, namely, (a) serum transferrins (present in plasma), (b) lactoferrins (present in milk and other secretions in mammals), (c) melanotransferrins (expressed on cell surface of melanoma cells), and (d) ovotransferrin (found in egg white). All of these proteins have iron binding ability that endows them with antimicrobial activity by rendering iron unavailable for the growth of microorganisms. It has been recently discovered that ovotransferrin interacts directly and binds with the surface proteins present on bacterial cells [2, 3]. Ovotransferrin is a single chain glycopeptide having a molecular weight of 77.9 kDa (total of 686 amino acids) with isoelectric point (pI) of 6.0 that makes it acidic in nature. It is made up of two homologous halves each possessing binding site for iron [4–8]. It also exists in two forms in nature, that is, apo-ovotransferrin (deprived of iron) and holo-ovotransfer- rin (saturated with iron) [9]. Holo-ovotransferrin is rela- tively more stable as apo-ovotransferrin is easily destroyed by physical and chemical treatments. Higher stability and metal binding properties were utilized to selectively isolate ovotransferrin [10]. It is the second most abundant protein in egg white afer ovalbumin, present at a concentration of 12-13% (v/v) in egg white protein [6]. It displays an array of bioactivities and it is considered as a potent candidate for Hindawi Publishing Corporation BioMed Research International Volume 2015, Article ID 934512, 10 pages http://dx.doi.org/10.1155/2015/934512