Biomedical Engineering Reference
In-Depth Information
Table 2
Some minerals containing enzymes
Mineral Enzyme Function
Cu Cytochrome oxidase Transport of electron during aerobic respiration
Cu Lysyl oxidase Formation of desmosine cross links in collagen and elastin
Cu Ceruloplasmin Iron absorption and transport for haemoglobin synthesis
Cu Tyrosinase Melanin production
Cu Superoxide dismutase Antioxidant in cells, play role in phagocytic cell Function
Zn Lactic dehydrogenase Plays role in glycolytic metabolism
Zn Carbonic anhydrase Assists rapid interconversion of carbon dioxide and water into
carbonic acid, protons and bicarbonate ions
Zn Copper zinc superoxide dismutase Antioxidant in cells
Se glutathione peroxidase Antioxidant in cells
Heme oxidase Function as antioxidant in protection of biological membranes
Mo Xanthine oxidase Generates reactive oxygen species and plays an important role
in the catabolism of purines
Source: Modified from National Research Council (
2001
)
when stimulated with Con A than cells of cows
fed on adequate levels of Cu (Torre et al.
1995
) .
Copper similar to zinc plays a vital role in
immune functions of all mammals. The Cu is an
integral part of enzymatic activity that affects
efficiency complex. It is also involved in proper
functioning of immune cells (macrophages and
neutrophils). A deficiency of copper has been
associated with a decreased ability of these cells
to multiply. Failure to multiply quickly may result
in a competitive advantage by mastitis-causing
bacteria. Diets with 20 ppm supplemental copper
have been shown to reduce the severity of masti-
tis following an
E. coli
challenge compared to
diets with 7 ppm (Scaletti et al.
2001
). Heifers
that received no supplemental copper after wean-
ing and then were fed a diet with no supplemental
copper from 84 days prepartum to 108 days
postpartum had more infected quarters during
lactation than did animals fed 20 ppm supple-
mental copper from 84 d pre- to 107 d postpar-
tum (Harmon and Torre
1994
) .
lipid peroxidation and radical formation, thus
having a strong pro-oxidant effect (Halliwell
1987
). The Fe plays role in the immune response,
and an insufficient supply causes anaemia in
deficient animals due to failure to produce hae-
moglobin. Fe deficiency is not common in adult
cattle as their requirement is low and Fe is ubiqui-
tous in the environment, but it is more frequent
in calves as milk Fe content is low (Underwood
1999
). In dairy cattle, plasma Fe concentration is
decreased during the acute phase response to
immunological challenges as are Zn concentra-
tions (Kushner
1982
), whereas plasma Cu con-
centration may increase (Andrieu
2008
) . These
ion changes reflect changes in cation binding of
plasma proteins and, more importantly, alterations
in cellular uptake mechanisms. During mastitis,
increased secretion of binding proteins such as
lactoferrin in milk decreases the amount of avail-
able Fe and thus reduces the availability of the
divalent Fe for growth of Gram-negative bacteria
(Todhunter et al.
1990
) .
7.2.4 Iron (Fe)
Iron in ferrous form (Fe
++
) performs a vital role
in many biochemical reactions, including (1)
antioxidant defence as an essential component of
catalase, (2) energy and protein metabolism, (3)
as a haem respiratory carrier, (4) oxidation-
reduction reactions and (5) in the electron trans-
port system. Reduced Fe is also a catalyst for
7.2.5 Manganese (Mn)
Mn plays an important role in body metabolism
as an essential part of a range of enzymes that are
involved in (1) antioxidant protection as an inte-
gral part of enzyme SOD, (2) bone growth and
formation of eggshell, (3) carbohydrate and lipid
metabolism, (4) immune and nervous function and
(5) reproduction. Like zinc and copper, manganese
