BOVINE
SERUM ALBUMIN:
Bovine serum albumin (BSA) is a large globular
protein (66,000 Dal) with a good essential amino acid profile . It has been well characterized and the
physical properties of this protein are well
known ( Peters, 1975).
BSA binds free fatty acids, other lipids and
flavor compounds, which can alter the heat denaturation of the protein
(Kinsella and Whitehead, 1992). Isolated
BSA has been reported to be a very functional protein (Waniska, et.al.,
1981). It is reported to partially
unfold between 40 and 50oC, exposing non-polar residues on the
surface and facilitating reversible protein-protein interactions. Phospholipid-protein-calcium complexes are
formed at pH levels below the isoelectric point of the BSA (Cornell, et.al.,
1990). Whether these interactions have
any biological function is not known.
Biological Function:
Bovine serum albumin has been given little
attention in respect to its role in the functional properties of whey protein
concentrates, and makes up only about 5% of the protein in whey protein
concentrates . Its primary biological
function has been associated with its lipid binding properties (Fox and Flynn,
1992), but the mechanism of this role
has not been clearly elucidated. It may
play a role in mediating lipid oxidation, since BSA has been shown invitro to
protect lipids against phenolic induced oxidation ( Smith, et.al, 1992; Koizumi
and Nonaka, 1975).
Strand (1995) claimed that denatured BSA might
“reduce the probability of a person acquiring certain diseases, such as insulin
dependent diabetes or auto-immune disease.
Bosselears, etal.
(1994) compared the anti-mutagenic effect of BSA, soy protein, total whey protein, b-lactoglobulin and pepsin-hydrolysed
casein. Of these proteins, only the
enzyme-hydrolysed casein and BSA were effective against genotoxic compounds.
Bovine serum albumin has been used as a
component of cell media to regenerate plants from cultured guard cells (
Tallman and Malibu, 1996) and to provide for enhancement of production of
plasminogen activator.