Delivery of sensitive health-promoting compounds in foods and beverages is an important goal, but also a highly challenging task.
Curcumin, a natural polyphenol and the major pigment of the turmeric root, is a potent antioxidant with numerous attributed health benefits including, anti-inflammatory, anti-proliferative and anti-angiogenic effects1,2. Preclinical and clinical trials suggest that curcumin can suppress tumor initiation, promotion and metastasis1. However the major obstacles limiting curcumin applicability as a food ingredient are its extremely low solubility in aqueous solutions and its poor bioavailability.
β-conglycinin (molecular mass ~190KDa) is the major protein in one of the two main protein fractions (glycinin (11s, ~52%) and conglycinin (7s, ~35%)) in soy bean flour. It is a glycoprotein and it shows better emulsification properties than glycinin3.
The aim of this research was to study the potential of using the β-conglycinin fraction (BCF) to form co-assembled nanovehicles for delivery of curcumin, thereby improve its water solubility and protect it against degradation, while using plant proteins (enabling “Kosher-Parve” status).
Using visible - light spectrophotometry we found high affinity between BCF and curcumin (binding constant 0.82-1.72x106M-1). The curcumin-BCF co-assemblies were much smaller than the curcumin aggregates without BCF. While without BCF the curcumin aggregates were several microns large and visible by eye, populations with BCF had a much smaller and bimodal size distribution, with average diameters of 65nm and 270nm, as measured by dynamic light scattering. Consequently, excellent transparency was maintained in the nanocomplex solutions, enabling their application in clear beverages. Moreover, BCF-curcumin co-assemblies were found to confer considerable protection to curcumin against light and oxygen induced degradation.
Principal Investigator: Prof. Yoav D. Livney Livney@technion.ac.il
References
1. Aggarwal, B. B.; Kumar, A.; Bharti, A. C., 2003, Anticancer Res 23, (1A), 363-98.
2. Kunchandy, E.; Rao, M. N. A., 1990, International Journal of Pharmaceutics 58, (3), 237-240.
3. Livney, Y. D., In Encapsulation Technologies and Delivery Systems for Food Ingredients and Nutraceuticals, Garti, N.; McClements, D. J., Eds. Woodhead Publishing Ltd.: 2012.
