Beta casein-micelle as a nano vehicle for solubility enhancement of curcumin; food industry application Mansoore Esmaili a , S. Mahmood Ghaffari a , Zeinab Moosavi-Movahedi b , Malihe Sadat Atri a , Ahmad Sharifizadeh a , Mohammad Farhadi c , Reza Yousefi d , Jean-Marc Chobert e , Thomas Haertlé e , Ali Akbar Moosavi-Movahedi a, f, * a Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran b Department of Chemistry, Faculty of Science, Tarbiat Modarres University, Tehran, Iran c ENT-HNS Research Center and Department, Tehran University of Medical Science, Tehran, Iran d Protein Chemistry Laboratory (PCL), Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran e UR 1268 Biopolymères Interactions Assemblages, INRA, équipe Fonctions et Interactions des Protéines, B.P. 71627, 44316 Nantes Cedex 3, France f Center of Excellence in Biothermodynamics, IBB, University of Tehran, Tehran, Iran article info Article history: Received 7 August 2010 Received in revised form 25 May 2011 Accepted 31 May 2011 Keywords: Beta casein micelle Curcumin Solubility K562 cell line Antioxidant activity abstract Curcumin is a potent anticancer and antioxidant natural polyphenol poorly soluble in aqueous solutions. Beta-casein (B-CN), an amphiphilic self-assembling protein that can form micellar nanostructures, could be used as a carrier system for hydrophobic therapeutic agents such as curcumin. In this study, camel B-CN was used for curcumin encapsulation. Critical micelle concentration of camel B-CN was determined at 25, 30 and 37  C using pyrene fluorescence and the solubility of curcumin was evaluated according to the solvent-evaporation technique. Presence of camel B-CN increased the solubility of curcumin at least 2500 fold. Analysis of fluorescence emission of curcumin showed that hydrophobic interactions are predominant in its formulation with B-CN. Additionally, the cytotoxicity of curcumin to human leukemia cell line K-562 was enhanced in the presence of B-CN micelles giving inhibitory concentration (IC 50 ) values of 26.5 and 17.7 mmol/L for free and encapsulated curcumin, respectively. Antioxidant activity of curcumin encapsulated in B-CN was higher than that of both free B-CN and curcumin. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Two main approaches are commonly used when inventing a new drug carrier. Either, the bulk material is dispersed in fine structures or molecules capable of self-assembly are used. Physi- cochemical properties of proteins including emulsification, foam- ing and gelation make them a good matrix in development of new nutraceutical applications and as drug delivery vehicles (Branco & Schneider, 2009; Chaudhry et al., 2008; Nezhadi, Choong, Lotfipour, & Dass, 2009; Torchilin, 2001). Curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)1,6-heptadiene -3,5-dione) is a polyphenol natural product derived from Curcuma longa (Chattopadhyay, Biswas, Bandyopadhay & Banerjee, 2004; Niranjan & Prakash, 2008) with antiproliferative (Kunnumakkara, Arnand, & Aggarwal, 2008; Shishodia, Chaturvedi, & Aggarwal, 2007; Schaaf et al., 2009), antiangiogenetic (Bhandarkar & Arbiser, 2007; Rafiee, Otterson, & Binion, 2008) and antioxidant properties (Ak & Gulcin, 2008), and it is of special importance among multi- target components in cancer chemotherapy (Goel, Jhurani, & Aggarwal, 2008). Curcumin is poorly soluble in water what is limiting its bioavailability (Singh, 2007), thus impending its conversion from cooking to clinical applications (Goel, Kunnumakkara, & Aggarwal, 2008). To increase curcumin bioavailability and incorporating it in functional foods, several carriers including hydrophobically modi- fied starch (Yu & Huang, 2010), cyclodextrins (Baglole, Boland, & Wagner, 2005), polyvinyl alcohol/polyvinyl alcohol hydrogel (Shah, Mishra, Kumar, Priyadarsini, & Bajaj, 2008), polymeric nanoparticles (Bisht et al., 2007; Thangapazham, Puri, Tele, Blumenthal, & Maheshwari, 2008) and bovine whole casein micelles (Sahu, Kasoju, & Bora, 2008) have been investigated. Worldwide efforts are taking place to discover and consume new sources of food proteins. Nowadays camel milk has become quite attractive from scientific and industrial points of view. However, the literature is lacking any basic and applied reports * Corresponding author. Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran. Tel.: þ98 21 66403957; fax: þ98 21 66404680. E-mail address: moosavi@ibb.ut.ac.ir (A.A. Moosavi-Movahedi). Contents lists available at ScienceDirect LWT - Food Science and Technology journal homepage: www.elsevier.com/locate/lwt 0023-6438/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.lwt.2011.05.023 LWT - Food Science and Technology xxx (2011) 1e7 Please cite this article in press as: Esmaili, M., et al., Beta casein-micelle as a nano vehicle for solubility enhancement of curcumin; food industry application, LWT - Food Science and Technology (2011), doi:10.1016/j.lwt.2011.05.023