38
F. B. SHORLAND
acids as well as even- and odd-numbered iso and odd-numbered anteiso
acids found in the rumen similarly result from the lower homologs produced by degradation of the proteins and carbohydrates in the rumen
[cf. Shorland (189)].
The fatty acid composition of the organ fats of animals as well as
the milk fats and fats secreted by sebaceous glands is discussed in
Section VI.
D. PLANT FATS
Included in this group are the fats of the simpler forms of plant
life, other than those already referred to in connection with aquatic
fats. In some of the cryptogams, and especially in bacteria, the lipids
are sometimes very complex and triglycerides are either absent or form
a minor part of the total lipid. Nevertheless, it is convenient to discuss
their fatty acids alongside those of the higher plants.
In the phanerogams, the seed fats and, to a lesser extent, the fruitcoat fats have been investigated. There is also information about the
composition of leaf lipids, but the lipids in other parts of the plants
have not yet been closely studied.
1. Cryptogam Fats
The component fatty acids of cryptogam fats have been given only
limited attention, and it is likely that further investigation will alter
current conceptions regarding the kinds of lipids and fatty acid types
in this group. Nevertheless, as will be shown in the description that
follows, many features not found in phanerogam lipids will be revealed,
as will the surprising differences between the species belonging to the
same family.
a. Fats of Bacteria. Among the bacterial lipids, the acid-fast bacteria, including especially tubercle bacilli, have received much attention.
The lipids of the acid-fast bacteria are unusual in lacking any appreciable amounts of the glycerides that form the most important part
of the depot fats of other species. The main constituents of acid-fast
bacteria are waxes of higher molecular weight branched-chain acids
(mycolic acids) and polysaccharides (190, 191).
The acetone-soluble "fats" of the acid-fast bacteria examined contain in addition to palmitic, stearic, oleic and linoleic acids, characteristic branched-chain fatty acids. Similar acids are also found in the
phospholipids. For example, in Mycobacterium leprae "fat" there are
present, dextrorotatory branched-chain acids with 16, 19, and 22 carbon
F. B. SHORLAND
acids as well as even- and odd-numbered iso and odd-numbered anteiso
acids found in the rumen similarly result from the lower homologs produced by degradation of the proteins and carbohydrates in the rumen
[cf. Shorland (189)].
The fatty acid composition of the organ fats of animals as well as
the milk fats and fats secreted by sebaceous glands is discussed in
Section VI.
D. PLANT FATS
Included in this group are the fats of the simpler forms of plant
life, other than those already referred to in connection with aquatic
fats. In some of the cryptogams, and especially in bacteria, the lipids
are sometimes very complex and triglycerides are either absent or form
a minor part of the total lipid. Nevertheless, it is convenient to discuss
their fatty acids alongside those of the higher plants.
In the phanerogams, the seed fats and, to a lesser extent, the fruitcoat fats have been investigated. There is also information about the
composition of leaf lipids, but the lipids in other parts of the plants
have not yet been closely studied.
1. Cryptogam Fats
The component fatty acids of cryptogam fats have been given only
limited attention, and it is likely that further investigation will alter
current conceptions regarding the kinds of lipids and fatty acid types
in this group. Nevertheless, as will be shown in the description that
follows, many features not found in phanerogam lipids will be revealed,
as will the surprising differences between the species belonging to the
same family.
a. Fats of Bacteria. Among the bacterial lipids, the acid-fast bacteria, including especially tubercle bacilli, have received much attention.
The lipids of the acid-fast bacteria are unusual in lacking any appreciable amounts of the glycerides that form the most important part
of the depot fats of other species. The main constituents of acid-fast
bacteria are waxes of higher molecular weight branched-chain acids
(mycolic acids) and polysaccharides (190, 191).
The acetone-soluble "fats" of the acid-fast bacteria examined contain in addition to palmitic, stearic, oleic and linoleic acids, characteristic branched-chain fatty acids. Similar acids are also found in the
phospholipids. For example, in Mycobacterium leprae "fat" there are
present, dextrorotatory branched-chain acids with 16, 19, and 22 carbon