Studies on Riboflavin in Milk:II. Partition of Riboflavin in Colostrum, Mid-and Late-Iactation Milk

概要

論文の詳細を見る
In order to clarify the influence of lactation upon the contents of total riboflavin and the composition ratio of riboflavin, the authors determined the contents of total riboflavin and changes in the composition ratio of riboflavin in colostrum, mid-lactation milk and late-lactation milk, using five cows for each lactation stage. The relationship between phosphatase activity and esterized-vitamin B2 contents was also studied.1. The average of total riboflavin contents in colostrum was about 2 to 3 times that in mid-lactation milk and decreased rapidly to the nomal value in 3 to 5 days after parturition. It was mainly the amount of flavin adenine dinucleotide (FAD) that decreased rapidly during this period. The percentage of esterized B2 in colostrum was much higher than that in nomal milk and the ratio of the 3 types of riboflavin in colostrum showed no transition to that of nomal milk even a week after parturition.2. The average of total riboflavin contents in mid-lactation milk was 170.2μg/100ml, which consisted of 18.1% FAD, 28.5% flavin mononucleotide (FMN), and 53.4% free riboflavin (FR). As lactation progressed, an increase in the ratio of bound riboflavin was obsered.3. The percentage of FR in such milk with high phosphatase activity as colostrum and late-lactation milk was lower than that in mid-lactation milk with low phosphatase activity.
公益社団法人日本畜産学会の論文