By S Al- Shokair

1. College of Veterinary Medicine & Animal Resources Department of Clinical Studies Toxicology & Forensic Medicine Tests For Detection of Toxic Substances in Plants and Pesticides By S Al-Shokair

2. Alkaloids Cyanognic Glycosides Chlorinated Hydrocarbone Coumarine Saponins

3. Alkaloids

5. Materials & Methods

6. Sample distillate (i.ealkaloids -atropine sulphate) 2N HCL Mayer’s reagent Wanger’s reagent Test tubes Pippets Beakers Racks

7. Alkaloids test reagents

8. Evaporate 2.5 g of alcoholic extract plant and dry Heat residue on a boiling water bath with 2N HCL Take 5 ml after cooling then filter Divide filtration into two portions Treat one portion with Mayer’s reagent Treat other with Wanger’s reagents

10. Results

11. Mayer’s & Wanger’sragents results

12. Alkaloids result Control

13. Alkaloids result Mayer’s and Wanger’s reagent

14. Cyanogenic Glycoside

16. Prussian Blue Test

17. Hydrogen cyanide (with the historical common name of Prussic acid) is a chemical compound with chemical formula HCN. Hydrogen cyanide is a colorless, extremely poisonous liquid that boils slightly above room temperature at 26 °C (79 °F). Hydrogen cyanide is a linear molecule, with a triple bond between carbon and nitrogen.

21. Materials & Methods

22. Sample distillate (i.e tissue; gastric contents/cyanid) 5% Na OH 2% Ferrous sulphate 10 % Ferric chloride Concentrated HCL Distilled water Pippets Test tubes Beakers Water bath

23. Prussian blue reagents

24. ` Make the distillate (5ml) slightly alkaline by 1ml of 5% sodium hydroxide. • Add one or two drops of freshly prepared 2% solution of ferrous sulphate. Add one drop of 10% ferric chloride. Shake well and warm gently on water bath. Cool and add few drops of concentrated hydochloric acid until the brown ferric hydroxide dissolves.

25. Results

26. A Prussian-blue precipitate will immediately appear if much cyanide is present A blue or bluish-green colour will appear if cyanide is present in trace only.

27. Prussian blue result

28. Styen’s test

29. Materials & Methods

30. Sample of distillate or minced material Dilute hydrochloric acid Picric acid 1 g Sodium carbonate 10 g Distilled water 100 A wide-macked flask Filter paper Water bath Beakers

31. Make a distillate slightly acid by dilute hydrochloric acid in a wide-nacked flask. Colse the flask with a cork having a slit. Soak filter paper with: 1. Picric acid 1g 2. Sodium carbonate 10 g 3. Distilled water 100 ml Dry filter paper in the air. Suspend strip of filter paper Do not touch strips the side of the flask. Incubate the flak at 37C for about 6-12 hours.

32. Results

33. Treated filter paper will change from yellow colour to brown colour, if cyanide is present.

34. Styen’s test result SS

35. Fujiwara test

37. Materials & Methods

38. Fujiwara test reagents

40. Sample distillate (i.e chlorinated hydrocarbon) Pyridine 10% sodium hydroxide Pippet Water bath Test tubes Beakers

41. To 5 ml of distillate in a test tube. Add 2ml of pure pyridine. Add 2 ml of 10% sodium hydroxide (Fresh) Place the mixture in a boiling water bath. Observe pyridine layer carefully during a two minutes interval.

42. Results

43. A pink or red colour in the pyridine layer will appear if halogenated hydrocarbone is present.

44. F

45. Coumarin

46. http://en.wikipedia.org/wiki/Coumarin • http://en.wikipedia.org/wiki/Warfarin

47. By bacteria or fungi in damaged plants, moldy hay and spoiled silage. Hay containing 0.002 to 0.003 per cent dicoumarol may poison cattle. Feeding trials with sheep have shown them to be about twice as tolerant.

48. Sweet clover • (Melilotus alba and M. officinalis

49. Melilotusofficinalis

50. Melilotus alba