Chemistry Reference
In-Depth Information
rats fed on the control diets. An elevation of serum hydroperoxide was also sup-
pressed in rats fed on milk whey and its fermented products. Sanders et al. (1995)
also reported that
Lactococcus lactis
demonstrated antioxidative superoxide dis-
mutase (SOD) activity. Likewise, whey from cultured skim milk increased anti-
oxidant enzymes in liver and RBCs of rats (Zommara et al., 1996). The activity
of SOD in RBCs and the activity of catalase in liver were elevated on feeding
cultured product diets compared with reference diets. In addition, the activity of
glutathione peroxidase in RBCs was higher on diet containing
Lactobacillus aci-
dophilus
compared to reference diet. The nonfermented whey diet was not effec-
tive in increasing antioxidant enzymes as with the fermented products. These
results suggest that fermented milk exerts a specific effect on oxidative stress. In
another study, Zommara et al. (1998) studied the antiperoxidative properties of a
fermented bovine milk whey preparation in rats fed on a low vitamin E diet and
identified the active principle in the preparation. They observed that fermented
milk product exerted an antiperoxidative activity in these rats. An exogenous sup-
ply of either an amino acid mixture or lactic acid stimulated the unfermented
whey proteins to prevent RBC hemolysis and to lower liver thiobarbituric acid
reactive oxygen substances (TBARS). The supply of whey proteins, particularly
β-lactoglobulin in the product resulted in an increase in liver reduced glutathione
(GSH) and prevented iron-mediated lipoprotein peroxidation.
In addition, many workers identified more lactic acid bacteria exhibiting anti-
oxidative activity. Lin and Yen (1999) identified five strains of
Streptococcus
thermophilus
and six strains of
L. delbrueckii
ssp.
bulgaricus
. Likewise, Lin
and Chang (2000) demonstrated antioxidant property of
L. acidophilus
ATCC
4356 and
B. longum
ATCC 15708. Terahara et al. (2000) studied the preventive
effect of
L . delbrueckii
spp.
bulgaricus
on the oxidation of LDL
in vivo
. Recently,
Kullisaar et al. (2003) reported that consumption of fermented goat's milk (made
using
L. fermentum
ME-3) improved antiatherogenicity in healthy subjects,
prolonged resistance of the lipoprotein fraction to oxidation, lowered levels of
peroxidized lipoproteins, oxidized LDL, 8-isoprostanes, and glutathione redox
ratio, and enhanced total antioxidative activity. Vibha (2004) and Kapila (2004)
reported increased activity of antioxidant enzymes, specifically, catalase, SOD,
and GPx, in RBCs of dahi, fermented milk, and probiotic cultures fed groups
of rats. The levels of lipid peroxides in RBCs and liver were observed to be sig-
nificantly lower in rats fed on fermented milk containing
L. casei
(Kapila et al.,
2006). Moreover, Choi et al. (2006) demonstrated that heat-killed lactic acid bac-
teria cells and fractionations of such treated cells could suppress the viability of
human cancer cells and inhibit the cytotoxicity associated with oxidative stress.
They isolated soluble polysaccharides from
L. acidophilus
606 and suggested that
these polysaccharides may constitute a novel anticancer agent, which manifests
a high degree of selectivity for human cancer cells and antioxidative agent in the
food industry.
