This paper is to report the biological value of the protein of decolored Scenedesmus determined by the method of Thomas and Mitchell. From the results obtained, the average biological value of casein and the protein of decolored Scenedesmus are 80.9 and 78.2 respectively on weanlirg rats and that of decolored Scenedesmus on adult rats is 70.7.
These experiments were designed to investigate the influence of extracting with methylalcohol and heat treatment on the digestibility of the protein of chiorella in vitro. The procedure of in vitro digestion of protein was carried out by usual method using trypsine and digestibility of protein in vitro was calculated. From the results, it is recognized that the digestibility of the protein of Chlorella can be apparently improved by extraction with methylalcohol.
In order to find out the absorption rate of chlorella by human experiment, the two healthy adults were chosen for examination. Certain side-dishes were given to-gether with biscuits in which 5% powdered chlorella was contained. They were allowed to take as much chlorella biscuits as possible in place of a portion of boild rice, intending to compare the absorption rate of chlorella with that of boiled rice. In this case powdered chlorella taken per day was 21-23g. According to the results, neither in fat nor in carbohydrate great differences were found concerning the absorption rate, but as to protein absorption, chlorella biscuits were evidently inferior to boiled rice.
The effect of extraction with methyl alcohol on the absorption rate of the protein of chlorella was investigated on albino rats. The average true absorption rates of casein, dried chlorella and decolored chlorella are 97.1%, 54.5% and 81.7% respectively and it is considered that the absorption rate of the protein of chlorella can be apparently improved by extraction with methyl-alcohol in case used on albino rats.
In order to investigate the true absorption rate of protein of decolored Scenedesmus on human subjects, 4 healthy adults were employed in this experiment. It was carried out of following 2 periods, one being a control period, another a experimental period. In both periods, all subjects were given basal diets for 3 days each, and in a experimental period, same subjects were given 40g of decolored Scenedesmus per head per day adding to the biscuits in the basal diets. The feces of all subjects in each period were collected and nutrient components of ingested diet and collected feces were analysed, and the true absorption rate of the protein of decolored Scenedesmus and the apparent absorption rate of each period were calculated with regard to these results. The average true absorption rate of decolored Scenedesmus is 74.6% and the influence of administration of Scenedesmus on the absorption rate of fat and carbohydrate of basal diets is little significant.
To know the essential amino acid intake of girls of high school, a dietary survey was carried out during seven days of 28 girls of Hakuo High School in Tokyo. And the essential amino acid intake was calculated with the table of amino acid composition in food by M. L. Orr and B. K. Watt. According to the result, their average daily intake of isoleucine being 3.68g., leucine being 5.39g., lysine being 3.73g., methionine being 1.52g., cystine being 1.08g., phenylalanine being 3.12g., threonine being 2.65g., tryptophan being 0.78g. and valine being 4.09g. In comparing the intake of the essential amino acid with the provisional protein pattern, the intake of methionine, sulfur-containing acid and tryptophan was low, 99, 81, 75, respectively.
A nutrition survey was carried out on the children in a institute in Tokyo, during from April to November 1956, to know the nutrient intake and eight essential amino acid intake of them. According to the result, calcium and vitamin intake was lower than the Dietary Allowances of Japanese. And their average daily intake of lysin being 2.99g., threonine being2.16g., methionine being 1.18g.. sulfur-containing amino acid being 1.01g. and tryptophan being 0.67g. In comparing the intake of the essential amino acid with the provisional protein pattern (FAO), the intake of methionine, sulfur-containing amino acid and tryptophan was low, 81, 81 and 73% respectively.