Állatorvosi jelentőségű növényi hatóanyagok egyszerű kimutatása tesztvizsgálatokkal

Abstract

SUMMARY The plant phytochemicals (mainly the secondary metabolites) can cause different types of toxicosis in our livestock and companion animals. In such cases (or in case of a suspicion) the chemical composition is very important. The rapid, simple demonstration (or exclusion) of a group of bioactive molecules can basically help the veterinarian’s work. The present publication would like to give a methodical guide for the veterinarians. Our publication summarises shortly the affected active compounds and gives methodical descriptions, documented with photos. The list of required chemicals and laboratory instruments is very simple; the number of specific reagents is low. Our work is based on the simple production of a plant extract (1 g plant/20 ml extractant) and demonstrates the following metabolites: cyanogenic glycosides, coumarins, tannins, cardiac glycosides, saponins, alkaloids and the nitrate ion. The HCN was liberated with H2SO4 from plants in a closed tube and a reddish colour was formed on a filter paper strip. Coumarins produce a yellow colour under strongly alkaline conditions; the tannins can react with FeCl3 molecules forming a bluish-blackish precipitation. Demonstration of cardiac glycosides is possible by Keller-Kiliani test, whereas a brown-brownish ring is formed at the interface of acetic acid-FeCl3 and of H2SO4. A stable foam layer, produced by shaking, can indicate the saponins. For the detection of alkaloids different reactions were used (including the orange-yellow precipitation by Dragendorff reagent, the bluish-purple colour by PDAB reagent and the brownish ring at the interface by Keller reaction). Nitrate ions can produce a yellow colour with diphenylamine on filtrate paper, induced by UV radiation. The methods were tested by samples of some frequent plant species, containing the affected metabolites. The presented methodical list can be developed according to possibilities and requirements of colleagues. We hope that the present publication can be useful for the veterinarians.