Biochemistry, Biophysics, and Structural Biology Commons^™

Concerning The Site Of Nitrogen Absorption In Rats Fed Autoclaved Or Raw Soybean Oil Mea, Raymond Borchers

Department of Biochemistry: Faculty Publications

Carroll, Hensley, and Graham (1) have concluded that much of the nitrogen absorption in rats fed raw soybean oil meal must take place in the cecum. This conclusion was reached from data showing that the apparent digestibility of raw soybean nitrogen in the terminal 20% of the small intestine was 32.65%, whereas in the feces the value was 76.96%. Values reported, for apparent digestibility of heated soybean nitrogen were 78.66% and 81.78%, respectively. This observation presented a notable advance in explaining the lower nutritive value of raw soybeans compared with autoclaved soybeans. It therefore seemed advisable to repeat this work …

Riboflavin Production By Molds, George L. Peltier, Raymond Borchers

Department of Biochemistry: Faculty Publications

Very little information is at hand regarding the ability of molds to synthesize riboflavin. Few citations pertaining directly to riboflavin production by true

molds are available. Pontovich (1943) found as much as 2 mg riboflavin per g

of Aspergillus flavus mycelium. Tanner et at. (1945) determined the quantity of

riboflavin in the submerged fermentation media of Penicillium chrysogenum.

The highest value found was 1. 36 mg per ml. The primary purpose of this study

was to screen several hundred isolates, recently obtained from soil, crop residues,

and composts, for their ability to produce riboflavin on a wheat bran substrate.

Threonine Deficiency In Hydrolysates Of Zein Prepared By Autoclaving, Raymond Borchers, John R. Totter, Clarence P. Berg

Department of Biochemistry: Faculty Publications

In a previous paper (Borchers and Berg, 1942) we showed that

autoclaving zein with sulfuric acid longer than necessary for complete

hydrolysis causes destruction and racemization; either of

these might account for the failure of such a hydrolysate to

promote growth in young rats when substituted for a hvdrolysate,

prepared by refiuxing, in a diet which produced moderate growth.

It seemed to us that this deterioration in the dietary protein might

well be the result primarily of essential amino acid deficiencies

which could be detected and overcome by appropriate supplementation.

Because threonine is known to be present in zein in …

The Effect Of Conditions Of Hydrolysis And Of Prolonged Heating Upon The Optical Rotation Of Sulfuric Acid Hydrolysates Of Zein, Raymond Borchers, Clarence P. Berg

Department of Biochemistry: Faculty Publications

Some time ago we observed that a sulfuric acid hydrolysate of zein prepared in an autoclave at 165˚ did not support growth in young rats when it was supplemented with certain amino acids, even though the same amino acids, added to a hydrolysate prepared by refluxing, permitted moderate growth. Since the optical rotation of the autoclaved hydrolysate was lower than that of the refluxed, either destruction or racemization of essential constituents, or both, might have occurred. Loss of amino nitrogen and production of extra ammonia upon prolonged autoclaving of proteins with acids have been noted by Van Slyke (1912) …

Tryptophane Metabolism X. The Effect Of Feeding 1(-)-, Dl-, And D(+)-Tryptophane, D(-)And Dl-(Β-3-Indolelactic Acid,(Β-3-Indolepyruvic Acid, And L(-)Kynurenine Upon The Storage Of Liver Glycogen And The Urinary Output Of Kynurenic Acid, Kynurenine, And Total Acetone Bodies, Raymond Borchers, Clarence P. Berg, Newton E. Whitman

Department of Biochemistry: Faculty Publications

The amount of tryptophane required for maintenance and growth is small (2). When an excess is supplied to some animals, kynurenic acid is excreted (3) and, under certain conditions, kynurenine also (4). Although these are quantitatively the most important of the known metabolic products of tryptophane, the amounts excreted in extensive tests in the dog and rabbit have usually accounted for less than half, more often for less than a third, of the tryptophane administered (4-6).