[Nutritional and biological experiences on low-erucic acid rapeseed oil "Janpol". Studies on rats after ingestion of "Janpol" oil and other edible fats]

Abstract

Comprehensive investigations were carried out for establishing the biological and nutritional value of low erucic-acid rapeseed oil from a variety of rape called Janpol selected in Poland. The pathophysiological effects of Janpol rapeseed oil were observed after giving it as the only source of fat in the diet or added in different proportions to other edible fats. In all cases the total amount of fat in the diet was 20 p. 100 kcal. The investigations were carried out on 78 young male Wistar rats aged 25 days at the beginning of the experiment. The rats were divided into 7 groups and they were given diets containing: 1) soybean oil; 2) mixed fats; 3) rapeseed oil of high erucic-acid content; 4) mixed fats containing 25 p. 100 of Janpol rapeseed oil; 5) mixed fats with 50 p. 100 of Janpol rapeseed oil; 6) mixed fats with 75 p. 100 of Janpol rapeseed oil; 7) Janpol rapeseed oil only. The experiment lasted 3 months. After its completion the rats were decapitated after 18 hours of starvation. The investigation s included : determination of weight gain, determination of the weight of selected organs (liver-lungs, heart, kidneys, testes, spleen), determination of alkaline phosphatase and pseudocholinesterase activity in the serum, determination of triglycerides and cholesterol in the serum, tests for adrenocortical function, histo-chemical investigations of the liver (alkaline and acid phosphatase, adenosine triphosphatase, fatty infiltration of the liver), macroscopic and microscopic anatomopathological examinations. The authors found the Janpol rapeseed oil caused less pronounced changes in the determined indices of the biological and nutritional evaluation as compared with high-erucic-acid rapeseed oil. Janpol repeseed oil given to experimental animals mixed with other fats in proportions of 25 p. 100 and 50 p. 100 of all fats in the diet, that is 5 p. 100 and 10 p. 100 kcal in the diet derived from Janpol oil gave in most determinations of the investigated parameters results very similar to those observed in animals receiving soybean oil. The results of these investigations show that Janpol rapesed oil can be used for nutrition of man in amounts not exceeding 10 p. 100 of the total caloric content of food.