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1. 1. The rate of fibrillogenesis by soluble collagen is reduced by ascorbic acid and dihydroxymaleic acid but not by dehydroascorbic acid. 2. 2. Upon incubation for 5 days with the inhibitors followed by dialysis, the ability to form gels is lost. Dehydroascorbic acid reduced the rate of fibrillogenesis. 3. 3. The normal electrophoretic pattern of collagen subunits was unaltered by treatment with dehydroascorbic acid for 5 days but was lost by treatment with the other two substances. 4. 4. In place of two distinct protein bands (ga 1 and ga 2 -chains) a diffuse region of stained material was observed. 5. 5. It is concluded that the ene-diol group is involved in both phenomena.

The cyclic carbonyl enediols, reductic acid and l-ascorbic acid, strongly retarded fat oxidation in frozen minced red spring salmon or herring flesh stored at −10 or −20 °C., the former being more effective than the latter. The acyclic carbonyl enediols and dihydroxymaleic acid with its sodium and ammonium salts and reductone were either ineffective or afforded only slight protection.

In the presence of hydrogen peroxide, crystalline turnip peroxidase catalizes a hydrogen-transferring reaction provided that suitable H-donor and H-acceptor are present. In this reaction triose reductone and dihydroxymaleic acid serve as H-donor, and methylene blue, thionine, and gaseous oxygen as H-acceptor.

1. The unadapted cells are not capable of adapting for ascorbic acid, even if they are in contact with ascorbid acid for a long time, but they can adapt rapidly in the presence of a small amount of glucose and of casein hydrolysate.2. Ascoraic acid-adapted cells degrade araboascorbic acid and glucoascorbic acid besides AsA, but fail to degrade other reductones, e.g., reductic acid, dihydroxymaleic acid and 5-methyl-3, 4-dihydroxytetrone.3. The optimal pH of the ascorbic acid-oxidase in the unadapted cells is 5.0 and the optimal substrate concentration is 800μM.4. The ascorbic acid-oxidase is inactive for the reductones other than ascorbic acid i.e., araboascorbic acid, glucoascorbic acid, reductic acid, dihydroxymaleic acid and 5-methyl-3, 4-dihydroxytetrone.