13.2 The Carbohydrate Spectrum of Cells and Extracellular Fluids
467
tose, trehalose, maltose, maltotriose and maltotetraose are found in proportions which vary
greatly with the season and moulting stage [251].
The blood-sugar level of the insects is almost
always higher than that of the other groups of
invertebrates. Trehalose usually predominates
and can reach concentrations as high as 70 gil
(e.g. in adult females of the aphid Megoura
viciae). Although glucose in the haemolymph of
insects rarely exceeds 10 % of the total carbohydrTable 13.1. The concentrations (mmol/l) of low molecular
weight carbohydrates in blood plasma and haemolymph.
The disaccharide and oligosaccharide concentrations are
given as mmol/l glucose equivalents
Species [Ref.]
Glucose Trehalose Fructose
Oligochaeta
Eisenia foetida [3]
1.3
Echiurida
Urechis caupo [3]
2.4
MoUusca
Helix pomatia [223]
1.2
_a
Octopus dofleini [3]
2.3
Cmstacea
Porcellio scaber [20]
Tr
Tr
Orconectes limosus [251]
October
0.26
0.16
Ob
March
0.63
0.33
0.45
Chelicerata
Hexathele hochstetteri [20]
0.36
0.26
Urodacus abruptus [20]
0.22
Tbysanura
Lepisma saccharina [20]
0.24
0.52
Insecta
Uropetala carovei [20]
0.47
4.2
Locusta migratoria [20]
Tr
43
Schistocerca gregaria [3]
1.3
39
Periplaneta americana [20]
3.1
38
Heimeidiens thoracica [20] 39
49
Gasterophilus intestinalis
larva [81]
0.56
10-16
Phormia regina [3]
33
7-167 -
Chalcophora mariana [81]
0
260
Galleria melonella [81]
1.2
94
Hyalophora cecropia [81]
0
36-64
Apis mellifica [35]
26
48
12
[7]
34
50
36
Vertebrates
Mammals
3-11
Birds
7-12
Reptiles
2- 9
Amphibians
0.5-1.6
Teleosts
1- 5
a + 0.13 galactose
b + 0.03 galactose + 0.014 maltose + 0.027 maltose disaccharide + 0.033 maltose tetrasaccharide + 0.13 hexurinoc
. acid + 0.017 sugar phosphates
Tr, trace amount
ate, it is consistently higher in concentration than
in other invertebrates (Table 13.1). A rather
unusual sugar spectrum for an insect is found in
the honey bee, where the haemolymph contains
glucose, fructose and trehalose in more-or-Iess
equal proportions. The blood sugar of the larvae
of the botfly Gasterophilus intestinalis, which
parasitizes the stomach of the horse, contains predominantly fructose.
Spermatozoa have no nutritional reserves of
their own and are dependent for their survival and
motility on energy-yielding substrates in the surrounding fluid. The seminal fluid of the higher
mammals (Placentalia) contains, above all, fructose as a nutrient for spermatozoa; in addition sorbitol and myo-inositol are present. Glucose is
almost entirely absent from the seminal plasma of
most mammals. The exceptions are humans, the
rat, mouse, guinea-pig and the field vole Microtus
agrestis, which have both fructose and glucose.
The main nutrient for the spermatozoa of the marsupials is N-acetylglucosamine; this sugar is also
found in the seminal fluid of several eutherians,
but is not used for example, by human sperm. In
some marsupials, e.g. the Tasmanian devil Sarcophilus harisii, the dasyure Dasyurus vivarrinus, the
wombat Phascolomys sp. and the North American
opossum Didelphis virginiana, the main carbohydrate in the seminal fluid is glycogen [227].
The main nutritional constituents of the milk
of the Placentalia are casein, milk fats and the
sugar lactose; these are present in species-specific
proportions (Table 13.2). The highest lactose
values are found in the milk of humans and other
Table 13.2. The sugar, fat and protein contents (%) of
milk [81]
Species
Sugar Fat Protein
Ape
Macaca mulatta
7.0
4.0 1.1
Human
Homo sapiens
7.0
3.8 0.4
Kangaroo Mageleia rufica
6.7
3.4 2.3
Horse
Equus caballus
6.2
1.9 1.3
Pig
Sus scrofa
5.5
6.8 2.8
Cow
Bos taurus
4.8
3.7 2.8
Cat
Felis catus
4.8
4.8 3.7
Elephant Elephas maximus
4.7
11.6 1.9
Opossum Didelphis marsupialis
4.1
7.0 2.8
Dog
Canis familiaris
3.1
12.9 5.8
Guinea-pig Cavia porcellus
3.0
3.9 6.6
Rat
Rattus norwegicus
2.6
10.3 6.4
Blue whale Balaenopetera musculus 1.3 42.3 7.2
Saddleback Pagophilus groenlandicus 0.9 52.5 3.8
Echidna
Tachyglossus aculeatus
0.9
9.6 7.3
Grizzly
Urus arctos
0.6 22.3 6.7
bear
467
tose, trehalose, maltose, maltotriose and maltotetraose are found in proportions which vary
greatly with the season and moulting stage [251].
The blood-sugar level of the insects is almost
always higher than that of the other groups of
invertebrates. Trehalose usually predominates
and can reach concentrations as high as 70 gil
(e.g. in adult females of the aphid Megoura
viciae). Although glucose in the haemolymph of
insects rarely exceeds 10 % of the total carbohydrTable 13.1. The concentrations (mmol/l) of low molecular
weight carbohydrates in blood plasma and haemolymph.
The disaccharide and oligosaccharide concentrations are
given as mmol/l glucose equivalents
Species [Ref.]
Glucose Trehalose Fructose
Oligochaeta
Eisenia foetida [3]
1.3
Echiurida
Urechis caupo [3]
2.4
MoUusca
Helix pomatia [223]
1.2
_a
Octopus dofleini [3]
2.3
Cmstacea
Porcellio scaber [20]
Tr
Tr
Orconectes limosus [251]
October
0.26
0.16
Ob
March
0.63
0.33
0.45
Chelicerata
Hexathele hochstetteri [20]
0.36
0.26
Urodacus abruptus [20]
0.22
Tbysanura
Lepisma saccharina [20]
0.24
0.52
Insecta
Uropetala carovei [20]
0.47
4.2
Locusta migratoria [20]
Tr
43
Schistocerca gregaria [3]
1.3
39
Periplaneta americana [20]
3.1
38
Heimeidiens thoracica [20] 39
49
Gasterophilus intestinalis
larva [81]
0.56
10-16
Phormia regina [3]
33
7-167 -
Chalcophora mariana [81]
0
260
Galleria melonella [81]
1.2
94
Hyalophora cecropia [81]
0
36-64
Apis mellifica [35]
26
48
12
[7]
34
50
36
Vertebrates
Mammals
3-11
Birds
7-12
Reptiles
2- 9
Amphibians
0.5-1.6
Teleosts
1- 5
a + 0.13 galactose
b + 0.03 galactose + 0.014 maltose + 0.027 maltose disaccharide + 0.033 maltose tetrasaccharide + 0.13 hexurinoc
. acid + 0.017 sugar phosphates
Tr, trace amount
ate, it is consistently higher in concentration than
in other invertebrates (Table 13.1). A rather
unusual sugar spectrum for an insect is found in
the honey bee, where the haemolymph contains
glucose, fructose and trehalose in more-or-Iess
equal proportions. The blood sugar of the larvae
of the botfly Gasterophilus intestinalis, which
parasitizes the stomach of the horse, contains predominantly fructose.
Spermatozoa have no nutritional reserves of
their own and are dependent for their survival and
motility on energy-yielding substrates in the surrounding fluid. The seminal fluid of the higher
mammals (Placentalia) contains, above all, fructose as a nutrient for spermatozoa; in addition sorbitol and myo-inositol are present. Glucose is
almost entirely absent from the seminal plasma of
most mammals. The exceptions are humans, the
rat, mouse, guinea-pig and the field vole Microtus
agrestis, which have both fructose and glucose.
The main nutrient for the spermatozoa of the marsupials is N-acetylglucosamine; this sugar is also
found in the seminal fluid of several eutherians,
but is not used for example, by human sperm. In
some marsupials, e.g. the Tasmanian devil Sarcophilus harisii, the dasyure Dasyurus vivarrinus, the
wombat Phascolomys sp. and the North American
opossum Didelphis virginiana, the main carbohydrate in the seminal fluid is glycogen [227].
The main nutritional constituents of the milk
of the Placentalia are casein, milk fats and the
sugar lactose; these are present in species-specific
proportions (Table 13.2). The highest lactose
values are found in the milk of humans and other
Table 13.2. The sugar, fat and protein contents (%) of
milk [81]
Species
Sugar Fat Protein
Ape
Macaca mulatta
7.0
4.0 1.1
Human
Homo sapiens
7.0
3.8 0.4
Kangaroo Mageleia rufica
6.7
3.4 2.3
Horse
Equus caballus
6.2
1.9 1.3
Pig
Sus scrofa
5.5
6.8 2.8
Cow
Bos taurus
4.8
3.7 2.8
Cat
Felis catus
4.8
4.8 3.7
Elephant Elephas maximus
4.7
11.6 1.9
Opossum Didelphis marsupialis
4.1
7.0 2.8
Dog
Canis familiaris
3.1
12.9 5.8
Guinea-pig Cavia porcellus
3.0
3.9 6.6
Rat
Rattus norwegicus
2.6
10.3 6.4
Blue whale Balaenopetera musculus 1.3 42.3 7.2
Saddleback Pagophilus groenlandicus 0.9 52.5 3.8
Echidna
Tachyglossus aculeatus
0.9
9.6 7.3
Grizzly
Urus arctos
0.6 22.3 6.7
bear