[The influence of yeast β-glucans on the assimilation of vitamins and mineral elements in rats].

Despite the use of yeast β-glucans in food and dietary supplements, there is insufficient data on their effect on the metabolism of vitamins and mineral elements. of the study was to evaluate the effect of β-glucans from Saccharomyces cerevisiae in the diet of growing rats on the absorption of micronutrients in animals deficient in vitamins D, group B and trace elements (iron, copper, zinc). . Micronutrient deficiency in male Wistar rats (initial body weight 61.6±0.8 g) was induced for 24 days by decreasing the content of vitamin D and all B vitamins in the vitamin mixture of the semi-synthetic diet by 5 times and the content of iron, copper and zinc in the mineral mixture by 2 times. After confirming the development of micronutrient deficiency in the animals, the missing vitamins and trace elements were added to the deficient diet for 5 days either along with β-glucan diet enrichment (1.5%) (+Vit+Met+βG) or without it addition (+Vit+Met). Vitamins B1 and B2 in the liver, riboflavin in the blood serum, thiamine, riboflavin and 4-pyridoxic acid (4-PA) in the urine collected for 18 hours were determined fluorimetrically; retinol, retinol palmitate, α-tocopherol in blood serum and liver - by high-performance liquid chromatography; minerals and trace elements in liver, serum and urine - by atomic absorption spectrometry or by standard methods on a biochemical analyzer. . A deficient diet for 24 days resulted in a decrease of B-vitamin status markers: riboflavin decreased in urine by 17.8- fold, in serum by 27.3% and in liver by 7.8%, vitamin B1 in liver by 3-fold, 4-PA in urine reduced by 2.8-fold (p<0.05). Urinary excretion of copper diminished by 25.7%, while the liver content of vitamin A increased by 44% and manganese by 19.2% (p<0.05). Replenishment of missing micronutrients in the diet, regardless of β-glucans presence, completely eliminated the deficiency of vitamin B2, while in the presence of the polysaccharide, rats of the +Vit+Met+βG group showed a statistically significant increase in vitamin B2 liver content by 7.5% (p<0.05) relative to the control, with an increased excretion of riboflavin by 19.1% (p<0.10) compared to excretion in +Vit+Met rats. Vitamin B1 liver level in animals of +Vit+Met and +Vit+Met+βG groups didn't completely restore to the control level but it was higher by 14.5% (p<0.05) in the presence of β-glucans. Urinary excretion of thiamine and 4-PA in rats fed β-glucan enriched diet reached the level of the control rats, while in rats from +Vit+Met group it amounted to 60.8-69.2% of the control. The diet with β-glucans caused a decrease in vitamin E liver content by 36.2% (p<0.05) compared to the level in +Vit+Met animals. Urinary excretion of iron and copper in the absence of β-glucans did not fully recover (amounting to 60.9-74.0% of the control), while in their presence it no longer differed from the value in animals of the control group. Zinc excretion in animals of the +Vit+Met+βG group, on the contrary, was lower than in the control by 29.2% (p<0.01). A decrease in serum magnesium (by 9.0%, p<0.05) with simultaneous increase (by 12.7%, p<0.10) in its urinary excretion under β-glucans' diet inclusion indicate a decrease in its retention and a deterioration in magnesium supply. . The presence of yeast β-glucans in the diet improved the absorption of B vitamins, promoted the absorption of iron and copper, but worsened the supply with vitamin E and magnesium, and reduced zinc assimilation.