EXPERIMENT NO 07. TO ISOLATE CAFFEINE FROM TEA POWDER | T.Y B. PHARM SEM - V | PHARMACOGNOSY & PHYTOCHEMISTRY – II

 

T.Y B. PHARM SEM - V

PHARMACOGNOSY & PHYTOCHEMISTRY – II

EXPERIMENT NO 07

AIM: TO ISOLATE CAFFEINE FROM TEA POWDER

REFERENCE:

1.     Dr. S. S. Khadabadi, Dr. S. L. Deore, B. A. Baviskar. Experimental phytopharmacognosy A Comprehensive Guide, Edition 1^st Published by Nirali prakashan, Page no. 5.8

 

2.     Dr. Anup K. Chakraborty, Sushma M. Rathod. “Practical in pharmacognosy & phytochemistry – II. Edition 2019, published by S. Vikas & company (Medical publisher), Page no. 34 – 36.

 

REUIREMENTS:

Apparatus: Separating funnel, Beaker, Stirrer, Funnel, Water bath, heating mantle, Porcelain dish, Measuring cylinder, Analytical balance etc.

Chemicals: Chloroform, Water. Tea powder,

INTRODUCTION:

TEA:

Synonym: Tea plant, Tea shrub, Camellia thea

Biological source: It consists of dried leaves and leaf bud of Thea sinensis.

Family: Theaceae

Chemical constituents: Nearly 4000 bioactive compounds contains in tea of which one third is contributed by polyphenols.

A large group of plant chemicals that includes the catechins (flavanols).

Major catechins are (-)-epicatechin gallate (ECG), (-)-epicatechin (EC), (-)epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG).

Green tea contains high concentration of these catechins than black tea.

Other compounds are purine alkaloids viz., caffeine, theophylline and theobromine. Trace compounds present in tea are amino acids, carbohydrates, proteins, chlorophyll, volatile organic compounds (chemicals that contribute to the odor of tea), fluoride, aluminum, minerals.

Uses: CNS stimulant, Diuretics, Antioxidant, Anticancer, Anti-Ageing effects, Obesity, Weight loss. Black and Green tea are extremely good source of vitamin C.

Caffeine: Caffeine is a naturally occurring substance found in the leaves, seeds or fruits of over 63 plant species worldwide and is part of a group of compounds known as methylxanthines. The most commonly known sources of caffeine are coffee, cocoa beans, cola nuts and tea leaves. Caffeine is a bitter, white crystalline xanthine alkaloid that is a psychoactive stimulant drug. Caffeine is pseudo alkaloid as it is not biosynthesized O CH, from amino acids, but gives all alkaloid identification tests positive.

Properties:

Color: White powder, White needles.

Odour: Odourless

Taste: Bitter

Solubility: Anhydrous caffeine is soluble in chloroform and alcohol. Sparingly soluble in water but solubility increases in water at 80 degree.

EXTRACTION METHODS.

1.     Weigh 10 g of tea leaves and transfer to 250 ml distilled water. Boil the water for 30 minutes with occasional Stirring. Then allow to cool and filter the solution.

2.     Take filtrate in a separating funnel and to it, add 100 ml chloroform. Shake vigorously so that total caffeine will be transferred to chloroform.

3.     Separate chloroform layer.

4.     Evaporate chloroform over water bath. White caffeine Crystals will collect at the bottom.

 

RESULT: The caffeine was isolated from tea powder. The percentage yield of caffeine was found to be……………..