Bioactive Components in Milk and Dairy Products - Prof. Dr. Aulanni ...

22 Section I: Bioactive Components in Milk
Also, LF increased weight gain in preweaning
calves. A recent study (Cornish et al. 2004 ) has
showed that oral LF administration to mice regulated
the bone cell activity and increased bone
formation. In addition animal studies have shown
benefi cial effects of LF ingestion on inhibition of
carcinogen - induced tumors in the colon, esophagus,
lung, tongue, bladder, and liver. Clinical studies in
infants with bovine LF preparations have demonstrated
that oral administration increased the number
of bifi dobacteria in fecal fl ora and the serum ferritin
level, while the ratios of Enterobacteriaceae, Streptococcus,
and Clostridium decreased. A recent clinical
study (King et al. 2007 ) has shown that LF
supplementation to healthy infants for 12 months
was associated with fewer lower respiratory tract
illnesses and higher hematocrits as compared to the
control group, which received regular infant formula.
Other human studies have shown that LF increased
the eradication rate of H. pylori gastritis when
administered in connection with triple therapy. Also,
LF ingestion decreased the incidence of bacteremia
and severity of infection in neutropenic patients. In
other human studies LF was shown to alleviate
symptoms of hepatitis C virus infection and reduce
small intestine permeability in drug - induced intestinal
injury. LF ingestion has also been shown to
promote the cure of tinea pedis. Recent human
studies reviewed by Zimecki and Kruzel (2007)
suggest that bovine LF administration could be benefi
cial in stress - related neurodegenerative disorders
and treatment of certain cancer types. For the reasons
above bovine LF has attracted increasing commercial
interest and many products containing added LF
have already been launched on the market in Asian
countries, in particular. LF is produced industrially
by many companies worldwide and it is expected
that its use as an ingredient in functional foods and
pharmaceutical preparations will increase drastically
in the near future (Tamura 2004 ). Current commercial
applications of LF include, e.g., yogurt
products marketed in Japan and Taiwan and baby
foods and infant formulas marketed in South Korea,
Japan, and China. In addition LF has been applied
in different dietary supplements that combine, for
example, LF and bovine colostrum or probiotic bacteria.
Due to potential synergistic actions LF has
been incorporated together with lysozyme and lactoperoxidase
into human oral health care products,
such as toothpastes, mouth rinses, moisturizing gels,
and chewing gums.
Lactoperoxidase
LP is a glycoprotein that occurs naturally in colostrum,
milk, and many other human and animal secretions.
LP represents the most abundant enzyme in
milk and can be recovered in substantial quantities
from whey using chromatographic techniques
(Kussendrager and Hooijdonk 2000). LP catalyzes
peroxidation of thiocyanate anion and some halides
in the presence of hydrogen peroxide source to generate
short - lived oxidation products of SCN - , primarily
hypothiocyanate (OSCN - ), which kill or inhibit
the growth of many species of microorganisms. The
hypothiocyanate anion causes oxidation of sulphydryl
(SH) groups of microbial enzymes and other
membrane proteins leading to intermediary inhibition
of growth or killing of susceptible microorganisms.
The complete antimicrobial LP/SCN/H202
system was originally characterized in milk by
Reiter and Oram (1967) . Today this system is considered
to be an important part of the natural host
defense system in mammals (Boots and Floris 2006 ).
A recent fi nding is the presence of LP in human
airway epithelia where it is likely to actively combat
respiratory infections caused by microbial invaders
(Gerson et al. 2000 ). In in vitro studies the LP
system has been shown to be active against a wide
range of microorganisms, including bacteria, viruses,
fungi, molds, and protozoa (Seifu et al. 2005 ). The
LP system is known to be bactericidal against Gram -
negative pathogenic and spoilage bacteria, such as
E.coli, Salmonella spp., Pseudomonas spp., and
Campylobacter spp. On the other hand, the system
is bacteriostatic against many Gram - positive bacteria,
such as Listeria spp., Staphylococcus spp., and
Streptococcus spp. This mechanism also is inhibitory
to Candida spp. and the protozoan Plasmodium
falciparium, and it has been shown to inactivate in
vitro the HIV type 1 and polio virus (Seifu et al.
2005 ). In view of the broad antimicrobial spectrum
against a variety of spoilage and pathogenic microorganisms
the LP system has been investigated
extensively for many potential applications. The LP
system is considered to provide a natural method for
preserving raw milk because milk contains naturally
all necessary components to make the system func-