~ 75 ~ The Pharma Innovation Journal 2018; 7(4): 75-79 ISSN (E): 2277- 7695 ISSN (P): 2349-8242 NAAS Rating: 5.03 TPI 2018; 7(4): 75-79 © 2018 TPI www.thepharmajournal.com Received: 01-02-2018 Accepted: 04-03-2018 Preeti Department of Animal Nutrition, National Dairy Research Institute, Karnal, Haryana, India Jagish Kour Reen Genetics Laboratory, Dairy Production Section, ICAR - National Dairy Research Institute, Southern Regional Station, Adugodi, Bengaluru, India Madhu Suman Assistant Professor, Instruction Livestock Farm Complex, College of Veterinary and Animal Sciences, Palampur, Himachal Pradesh, India Uday Kannegundla Genetics Laboratory, Dairy Production Section, ICAR - National Dairy Research Institute, Southern Regional Station, Adugodi, Bengaluru, India Manjula Thakur Department of Animal Nutrition, National Dairy Research Institute, Karnal, Haryana, India Rohit Kumar Department of Animal Nutrition, National Dairy Research Institute, Karnal, Haryana, India Correspondence Preeti Department of Animal Nutrition, National Dairy Research Institute, Karnal, Haryana, India A multifunctional bioactive protein: Lactoferrin Preeti, Jagish Kour Reen, Madhu Suman, Uday Kannegundla, Manjula Thakur and Rohit Kumar Abstract Lactoferrin which is also known by the name of lactotransferrin (LTF), is a multifunctional iron-binding glycoprotein of the transferrin family and is found in almost all human mucosal secretions as well as in the specific granules of polymorphonuclear leukocytes in blood. A variety of functions have been found to associated with this protein along with its contribution to antimicrobial host defense mechanism. Moreover, it has been shown to have direct effects on some of the pathogenic microorganisms through bacteriostatic and microbial iron uptake induction. Several studies have shown that the protein synergistically interacts with immunoglobins, complement, and neutrophil cationic proteins which act against Gram-negative bacteria. Further, both the whole protein and a cationic N-terminus peptide fragment directly damage the outer membrane of Gram-negative bacteria suggesting a mechanism for its supplemental antimicrobial effects. It has appeared logical that antimicrobial activity of the protein arises from sequestration of environmental iron thereby causing nutritional deprivation of iron in susceptible organisms. Lactoferrin has diverse role where it can be used as an immunotherapeutic and can also play a role in immunodiagnostics. Still its overall physiologic role remains yet to be defined clearly inside the living system. Keywords: lactoferrin, antimicrobial, immunomodulator, antioxidant 1. Introduction Milk is the primary source of nutrients for young mammalians. It is recognized as being nutritionally balanced and has therefore attracted a lot of scientific interest over the years. Various properties of intact milk proteins have been reported including satiating, antimicrobial, mineral binding, antilipidemic and anticancer properties (Paesano, 2014; Kanwar et al., 2014; Zhang et al., 2014; Nakamura et al., 2013) [38, 22, 33] . Identification of large number of peptides in milk protein hydrolysate make the milk proteins as one of the most important source of bioactive peptide. Several authors have suggested that milk protein- derived bioactive proteins may be used as prophylactic agents to alleviate symptoms of various diseases in humans. Side-effects of various drugs used to cure/slow down the progress of specific diseases in humans may sometimes outweigh their benefits (Onishi, 2011; Agrawal et al., 2009) [37] . Further increasing awareness regarding potential benefits of milk protein derived bioactive peptide among the people laid path of growing milk nutraceutical market (Nagpal et al., 2011) [32] . Lactoferrin (Lf) is a non-heme iron binding glycoprotein with molecular weight of 78 kDa that contains around 690 amino acid residues. It belongs to the transferrin (Tf) family. This protein is almost found in all exocrine secretions including saliva, tears, semen, vaginal fluids, gastrointestinal fluids, nasal mucosa and bronchial mucosa of human being (Iigo et al., 2009; Birgens et al., 1985) [20, 3] . Lactoferrin is also found in milk of bovine, caprine, camel and human (Saltanat, 2009) [45] . Lf is also known for its anti-bacterial, antifungal, antiviral, antimicrobial, anti-oxidant, anti-inflammatory, anti-parasitic, anti-allergic and most importantly anti-cancerous properties (Iigo et al., 2009; Parhi et al., 2012) [56, 40] . Lf is the second most abundant milk protein after casein and its highest concentration is found in human colostrum and then human milk followed by cow milk (Sanchez et al., 1992) [46] . Development of drug-resistant cancers imposed question mark on the use of chemotherapeutic agents. This limitation raises the need of a natural substitute that has generalized acceptance and can possibly completely eradicate the primary tumor, thus eliminating the risk of recurrence. In this context Lf has got the potential to be used as anticancer bio-molecule. Lactoferrin: Structure and Functions The structure of Lf consists of a single polypeptide chain which is folded into two lobes