Average increase in chain length of crystalline long chain compounds per carbon atom

1973 ◽  
Vol 50 (7) ◽  
pp. 245-248 ◽  
Author(s):  
Evald L. Skau
1962 ◽  
Vol 40 (7) ◽  
pp. 1326-1338 ◽  
Author(s):  
A. P. Tulloch ◽  
J. F. T. Spencer ◽  
P. A. J. Gorin

The yield of extracellular glycolipid produced by Torulopsis magnoliae is increased three-to five-fold by the addition of suitable compounds to the growing culture. The supplement, which can be a long-chain acid, ester, hydrocarbon, or glyceride, is hydroxylated and converted to hydroxy fatty acid sophorosides. Fatty esters of all chain lengths from C16 to C22, including several unsaturated esters, and even-numbered hydrocarbons from C16 to C24 are readily fermented. Shorter-chain compounds are used poorly or not at all. With compounds of 16 to 18 carbon atoms, hydroxylation occurs at the terminal or penultimate carbon atom, depending on degree of unsaturation and chain length. Substrates of more than 18 carbon atoms are mainly reduced in chain length by one or more two-carbon units and hydroxylated, giving C17 or C18 acids with the hydroxyl group on the penultimate carbon atom. The various enzymic reactions which occur during the fermentation are discussed.


A paper by R. W. Sillars of the National Physical Laboratory was published under the above title in 1938. Sillars showed how the relaxation time of long-chain esters embedded in a paraffin wax medium depended upon the chain length of the ester. It is well known that many properties of long-chain compounds alternate according as the number of carbon atoms is odd or even. Accordingly, Sillars was careful to use only esters with an even number of carbon atoms in order to reduce the number of possible variables affecting his investigations. He hoped the esters with an odd number would be examined later, and accordingly the work described in this paper was undertaken for the purpose of filling in an obvious gap in Sillars’s experiments and to be complementary to them.


1969 ◽  
Vol 244 (4) ◽  
pp. 882-888 ◽  
Author(s):  
E Heinz ◽  
A P Tulloch ◽  
J F T Spencer
Keyword(s):  

1996 ◽  
Vol 1996 ◽  
pp. 98-98
Author(s):  
B M L McLean ◽  
R W Mayes ◽  
F D DeB Hovell

Alkanes occur naturally in all plants, although forage crops tend to have higher alkane contents than cereals. N-alkanes have odd-numbered carbon chains. They are ideal for use as markers in feed trials, because, they are inert, indigestible and naturally occurring, and can be recovered in animal faeces. Synthetic alkanes (even-numbered carbon chains) are available commercially and can also used as external markers. Dove and Mayes (1991) cite evidence indicating that faecal recovery of alkanes in ruminants increases with increasing carbon-chain length. Thus the alkane “pairs” (e.g. C35 & C36, and C32 & C33) are used in calculating intake and digestibility because they are long chain and adjacent to each other. However, recent work by Cuddeford and Mayes (unpublished) has found that in horses the faecal recovery rates are similar regardless of chain lengths.


1993 ◽  
Vol 24 (8) ◽  
pp. 527-532 ◽  
Author(s):  
Fumitoshi Kaneko ◽  
Masamichi Kobayashi ◽  
Hirotoshi Sakashita

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