874 XIV. NUTRITIONAL VALUE OF FATS 



fluorescent pigment which it produces, P. oleovorans (which forms fluores- 

 cent colonies on oil-w^ater emulsions), and P. fragi (from milk and dairy 

 products, characterized by its strawberry odor) which is strongly lipo- 

 clastic. P. fluorescens was found to be especially active in the hydrolysis 

 of butter oil (90.7%) ; coconut oil and tallow were also strongly hydrolyzed 

 (80.8%), and lard, soybean oil, and peanut oil w^ere split to a lesser degree 

 (74.3 to 79%). P. fragi also hydrolyzed butter oil to the extent of 75.2%. 

 On the other hand, the bacterial groAvth rate in butter oil emulsion in- 

 creased sharply up to the fifth day of incubation, from an initial count of 

 350 to 7000 million bacteria/ml. of culture, and then fell precipitously 

 after the twenty -fifth day from 1300 to 35, and to 0.001 on the forty -second 

 day. As the acidity of the culture increased, the number of viable cells 

 declined. 



Trypanosoma evansi (an animal microparasite, found in India, which 

 causes "surra" disease of horses and mules), suspended in a buffered 

 Ringer solution, is able to oxidize the sodium salts or methyl esters of the 

 lower fatty acids, formic, acetic, propionic, butyric; the acids are split by 

 both jS- and w-oxidation.^^^ 



Fat is found in surface cultures of Aspergillus nidulans ( a fungus causing 

 white mycetoma). The amounts of both saturated and unsaturated 

 acids (oleic, linoleic, linolenic) increase up to the ninth day of incubation, 

 and then gradually decrease.^" Singh et al.^^^ found that the proportion 

 of saturated fatty acids produced by Penicillium lilacinum (soil mold 

 forming rosy and violet colonies) was markedly greater than in most fats 

 of microbiologic origin. Palmitic comprised 32.3% of the total fatty 

 acids (75% of the total saturated acids), myristic, 0.1%; stearic, 9.4%; 

 arachidic, 1.4%; hexadecenoic, 3.4%; oleic, 38.6%; linoleic, 13.4%; 

 C20 unsaturated acids, 1.4%. 



h. Miscellaneous Stress Factors. Clayton and Baumann^^^ reported 

 that, when rats and mice were given 2,4-dinitrotoluene, growth was better 

 and mortality was lower on a 30% fat diet than when the diet provided 

 only 5% of fat. Beneficial effects of fat in minimizing the toxicity of DNT 

 were noted with cottonseed oil, corn oil, Crisco, hydrogenated coconut oil, 

 lard, and butterfat. It w^as suggested that the harmful effects of dinitro- 

 toluene on the low-fat diets could be ascribed to the low caloric intake of 

 the mice. Rancid cottonseed oil, on the other hand, was found to accentu- 



1" M. Manozzi-Torini, Arch. sci. hiol. {Italy), 26, 565-580 (1940). 



1" J. Singh and T. K. Walker, Biochem. J., 62, 286-289 (1956). 



1" J. Singh, S. Shah, and T. K. Walker, Biochem. J., 62, 222-224 (1956). 



ifs C. C. Clayton, and C. A. Baumann, Arch. Biochem., 16, 415-422 (1948). 



