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The aim of the study was to determine whether high doses of Vitamin C may alleviate the effects of oxidative stress caused by ozone, or whether they actually intensify its course and demonstrate pro-oxidative activity. The experiment was conducted on adult male rats divided into 6 groups: Group I - control animals; Group II and III - animals which were simultaneously ozonated and administered intramuscular injections of Vit C in doses of 20 and 40 mg/rat respectively; Group IV and V - non-ozonated animals, which were administered the above doses of Vit C every fifth day for a period of 35 days; Group VI - rats ozonated without Vit C. The results of the study indicated that the highest level of indexes defining the intensity of oxidative stress occurred both in animals which were ozonated and given high doses of Vit C as well as in non-ozonated animals which were given high doses the vitamin. AST activity and glucose levels were also highest in the above groups and displayed a similar pattern. It may thus be assumed that high doses of Vit C do not prevent organisms from ozone-induced oxidative stress, and may even increase its intensity
The objective of the study was to demonstrate the course of the vit. C synthesis process in broilers from their 1st to 56th days after hatching as compared to their organ growth and body mass. The vit. C level was established according to Roe-Kuether’s method in the liver, spleen, kidneys and heart of 56 broilers slaughtered in groups of six birds every week. It was proved that in the chicken broilers in their embryonal stage, the greatest amount of vit. C was synthesized by kidneys - 160.6 mg/kg of tissue, then liver - 143.0 mg/kg, slighty less by the spleen - 107.3 mg/kg and heart - 99.0 mg/kg of tissue. Over the first two months vit. C synthesis in the liver increases together with age (from 143.0 to 291.5 mg/kg tissue). The liver weight growth in the first period is similar and proportional to body weight growth, therefore it can be assumed that the liver is a substantial source of vit. C over the first two months after hatching. In the spleen, the vit. C synthesis expressed in mg/kg of tissue was the highest on the first day of life after which it decreased (from 107.3 mg/kg to 56.1 mg/kg) However, an intensive organ weight growth, as much as 56.4 times, caused a considerable increase of the vitamin synthesis by the whole organ (from 0.0108 to 0.316 mg/whole organ). In the first 56 days of the life the heart synthesizes an almost identical amount of vit. C (about 99.0 to 110.0 mg/kg), in terms of mg/kg of tissue. The body weight growth was higher than that of the heart weight (30.5 times and 61.8 times). It should be stated that the heart in this period of time provides a decreasing amount of vit. C. An intensive vit. C synthesis appears in the kidney - from 160.6 mg/kg to 215.6 mg/kg. As kidney weight growth was nearly the same as body weight, it should be confirmed that the kidneys are a major source of vit. C for a young body. Vit. C. synthesis in broilers throughout their first two months increases together with age, yet in some unfavourable environment conditions it may be insufficient. That is way it would be advisable to administer vit. C as a preventive over this period of time.
W pracy przedstawiono wyniki badań nad wpływem pH środowiska na aktywność przeciwrodnikową kwercetyny w obecności witaminy C (kwasu askorbinowego). Stwierdzono, że aktywność przeciwrodnikowa kwercetyny, zmierzona w teście TEAC (Trolox Equivalent Antioxidant Capacity), ulega znacznemu obniżeniu w pH 4,5-9,0 w wyniku interakcji z kwasem askorbinowym. Wykonano odpowiednie obliczenia kwantowo-chemiczne w celu wyjaśnienia obserwowanego antagonistycznego oddziaływania pomiędzy tymi przeciwutleniaczami.
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