Chemical nature of Crude drugs PH103.71

2 Recap Glycosides Different types of Glycosides In the last class we learnt about

PH Examples of different types of Glycosides Examples of Tannins On completion of this period, you would be able to know Objectives

PH Flavones are Phenyl benzopyrone derivatives They may occur in form of Flavone Flavanol Flavanone Isoflavone Chalcone Flavonoid Glycosides

PH Responsible for colours Cyanidin in Rose and Corn flowers Malvidin in purple grapes Anthocyanidin Glycosides

PH Anthracene Glycosides Senna leaf Cassia aungustifolia Aloe Aloe vera Senna pods Cassia acutifolia Rhubarb Rheum emodi Cascara Rhamnus purshiana Summary of Glycoside Containing Crude Drugs

PH DigitalisDigitalis purpurea Red squillUrginea maritima StrophanthusStrophanthus kombe Indian SquillUrginea indica Thevetia Thevetia nerifolia Steroidal Glycosides

PH Dioscorea Dioscorea deltoidea Liquorice Glycyrrhiza glabra Shatavari Asparagus racemosus Brahmi Bacopa moniera Saponin Glycosides

PH Bitter almondPrunus amygdalus Wild cherry bark Prunus serotina Cyanogenetic Glycosides

PH Black mustard Brassica nigra Isothiocyanate Glycosides

PH Silmarin Silbus marianum Citrus-fruits Lemon Citrus limonis Orange Citrus aurantium Flavonol Glycosides

PH Ammi Ammi majus Psoralea Psoralea corylifolia Coumarin and Furanocoumarin Glycosides

PH Gentian Gentiana lutea Chirata Swertia chirata Quassia Picrasma excelsa Gymnema Gymnema sylvestre Miscellaneous Glycosides

PH Tannins comprise of a large group of Complex Organic Non-nitrogenous Phenolic compounds with high molecular weight Polyhydroxy benzoic acid derivatives capable of combining with protiens Tannins

PH Tannins They have property to combine with proteins of animal skin convert it into leather Tannins are amorphous in nature Soluble in water, Alcohol,Astringent in taste Precipitate proteins Produce acidity reaction

PH Tannins Due to Polyphenolic with Ferric chloride solution Tannins give Blue, Green, Black Violet colour / precipitate Tannins also give ppt. with gelatin, antipyrine, Alkaloids, Heavy metallic salts, Proteins

PH Tannins Tannins can be classified Condensed tannins Hydrolysable tannins Pseudo tannins

PH Tannins Condensed tannins formed by Catechins & Flavonols When heated produce catechol Condensed tannins give green colour When reacted with dil. Hydrochloric acid Phloroglucinol is produced Light coloured phlobatannin are converted into insoluble dark coloured Phlobaphenes eg: Cinchona

PH Tannins Hydrolysable tannins are esters When hydrolysed with acids or enzymes produce gallic acid or ellagic acid With ferric chloride they produce Blue or black colour / precipitate On heating they yield pyrogallol Eg: Clove, Rhubarb, Myrobalan

PH Tannins Bahera Terminalia belerica Arjuna Terminalia arjuna Tannic Acid Quercus infectoria Amla Emblica officinalis Ashoka Saraca indica Black catechu: Acacia catechu Pterpcarpus Pterocarpus marsupium

PH Summary In this class we learnt about Different types of Glycosides Examples of Tannins

PH Quiz The bark which is used as Cardiotonic a)Arjuna b)Cinchona c)Cinnamon d)Kurchi

PH Quiz Tannins react with Ferric Chloride give rise to a)Blue b)Green c)Black d)All the above

PH Frequently Asked Questions 1.Explain in detail about Tannins with examples?