ALKALOID COMPOUND ISOLATION EXPERIMENTAL REPORT

CHEMISTRY EXPERIMENTAL REPORT

COURSE       : ORGANIC CHEMISTRY REACTION EXPERIMENTAL

ALKALOID COMPOUND

ISOLATION

BY:

NAME                                                : FELIX VALENTINO SIANTURI

NIM                                                    : 4183131033

DEPARTMENT                                : CHEMISTRY

PROGRAM                                       : S1-BILINGUAL CHEMISTRY EDUCATION

GROUP                                              : I

IMPLEMENTATION DATE           : OCTOBER, 28^TH 2019

FACULTY OF MATH AND SCIENCE

MEDAN STATE UNIVERSITY

MEDAN

A.    TITLE      :           ALKALOID COMPOUND ISOLATION

B.     OBJECTIVE       :

1.      To find out isolation of alkaloid compound with extraction method by using soxhlet

2.      To find out the caffeine crystal in green tea with extraction method by using soxhlet

C.    THEORETICAL REVIEW      :

The technique used to separate an organic compound from a mixture of compounds is called Extraction. Extraction process selectively dissolves one or more of the mixture compounds into a suitable solvent. The solution of these dissolved compounds is referred to as the Extract. Here the organic solvent dichloromethane is used to extract caffeine from an aqueous extract of tea leaves because caffeine is more soluble in dichloromethane (140 mg/ml) than it is in water (22 mg/ml). However, the tannins that are slightly soluble in dichloromethane can be eliminated by converting it to their salts (phenolic anions by adding sodium carbonate) (tannins are phenolic compounds of high molecular weight and being acidic in nature can be converted to salts by deprotonation of the -OH group) which remain in the water.

Beverages cover a vast variety of addictive drinks out of which Tea and Coffee are the most popular acceptable drinks. Tea powder is extracted from tea leaves which contain tannins, which are acidic in nature, a number of colored compounds and a small amount of unrecompensed chlorophyll and an important stimulant called Caffeine. Because of the presence of Caffeine, tea and coffee are gaining popularity as an addictive stimulant. An average 30g of tea can contain 20-ll0 mg of caffeine thereby making tea a significant source of caffeine compared to other beverages. Caffeine can stimulate nervous system and can cause relaxation of respiratory and cardiac muscles.  Caffeine is well known to increase both the alertness level and attention span. But like all other addictive, tea also shows withdrawal symptoms like headache, nervousness and insomnia for a regular consuming person.

Caffeine, 1, 3, 7 - trimethylxanthine, belongs to a wide class of compounds known as alkaloids. These are plant derived compounds with complex structure containing nitrogen, and usually have roles in physiological activity. The melting point of Caffeine is 238°C (Pavia, 2010).

Caffeine and other purine alkaloids, including theobromine and theophylline, have played a major role in the long-standing popularity of non-alcoholic beverages and foods such as coffee, tea, cocoa, mate, chocolate and a wide range of soft drink. Caffeine is a naturally occurring chemical stimulant found in the leaves, seeds and fruits of a numerous plant species of a group of compounds called trimethylxanthine. Its chemical formula is C₈H₁₀N₄O₂. In its pure form, caffeine is a white crystalline powder that tastes very bitter. It is medically useful to stimulate the heart and also serves as increasing the rate of urine excretion.  It is one of the most studied ingredients in the food supply. The most commonly known sources of caffeine are coffee and cocoa beans, guarana, and tea leaves. The amount of caffeine in food and beverage products varies depending on the serving size, the type of product and preparation method. Tea which we generally drink is made from the leaves of an Asian evergreen known as Camellia sinensis. White tea, green tea, red tea, and black tea all come from this plant, and all contain caffeine. The presence of caffeine in plants helps to prevent them from insects and other herbivores with the compound’s bitter taste and stimulating qualities. The growing buds and young leaves of tea plants manufacture the highest amounts of caffeine (Rebecca, 2014).

Caffeine is a psychoactive CNS stimulant drug discovered by German chemist Friedrich Ferdinand Runge in 1819. He coined the term ‘Kaffein’ which became Caffeine. It is a natural pesticide. Caffeine does not counteract the effects of alcohol. Caffeine is a xanthine alkaloid compound that acts as a stimulant in humans. It is a central nervous stimulant, having the effect of temporarily warding off drowsiness and restoring alertness. Along with nicotine and alcohol, caffeine is one of the three most widely used mood affecting drugs in the world (Pradeep, 2015).

D.    APPARATUS AND MATERIAL        :

1.      Apparatus

No	Name of Apparatus	Specification	Amount
1	Soxhlet	-	1
2	Hot plate	-	1
3	Filtered paper	-	Sufficiently
4	Boiling stone	-	Sufficiently
5	Beaker glass	800 ml, 300 ml, 250 ml, 100 ml	5
6	Spatula	-	1
7	Measuring glass	100 ml	1
8	Scale	-	1
9	Droppers	-	2
10	Volumetric pipette	10 ml	1
11	Suction ball	-	1
12	Funnel	-	2
13	Volumetric flask	100 ml	1

2.      Materials

No	Name of materials	Molecular formula	[M]	Phase	Color	Quantity
1	Ethanol	C2H5OH	-	Liquid	Colorless	250 ml
2	Magnesium oxide	MgO	-	Solid	White	25 g
3	Sulfuric acid	H2SO4	1%	Aqueous	Colorless	25 ml
4	Chloroform	CHCl3	-	Liquid	Colorless	15 ml
5	Sodium hydroxide	NaOH	1%	Aqueous	Colorless	15 ml
6	Aquadest	H2O	-	Liquid	Colorless	Sufficiently
7	Tea powder sample	-	-	Solid	Brownish	25 gr

E.     WORK PROCEDURE  :

1.      Weight 25 g of tea powder sample

2.      Wrap the tea powder sample into the big filter paper

3.      Put it into the thimbel

4.      Add ethanol into the boiling flask

5.      Do the soxhletation until the extracts of the tea have been extracted

6.      Put MgO into the beaker glass, then put the tea extraction into it

7.      Place the beaker glass over the hot plate and warm up to get the powder mixture between MgO and tea extraction

8.      Enter aquadest into another beaker glass and warm it up, after that, enter the powder mixture to it

9.      Shake the mixture, then filter the mixture using filtered paper to throw the mixed pulp away

10.  Add H₂SO₄ into the mixture, and then warm it up until the remaining volume of mixture is the one third of the initial volume

11.  Enter CHCl₃ and NaOH into the new mixture and shake it

12.  Enter the mixture into the separatory funnel

13.  Shake the separatory funnel to get colorless phase in the bottom layer

14.  Take the colorless phase from the bottom layer

F.     RESULT, REACTION, AND DISCUSSION :

1.      Result

No	Treatment	Result
1	During soxhletation	·         Color of solution during soxhletation process was dark brown. ·         Time for soxhletation process was ±35 minutes. ·         The color of solution was light green.
2	The solution was added with MgO	·         The color was cloudy green. ·         After being heated, the solution turned to be powder, the color was green. ·         Powder weight = 27,38 g.
3	The powder was added with water	·         The color was dark brown.
4	The mixture was filtered by filtered paper	·         The color was reddish brown. ·         The tea becomes darker and produce tea smell.
5	The mixture was added with H2SO4 and warmed up	·         The remaining mixture volume was one third of the initial volume.
6	The mixture was added with CHCl3, NaOH	·         Formed 2 layers, upper = brownish, lower = colorless.
7	The mixture was shaked and separated in the separatory funnel	·         Formed 2 layers, upper = brownish, lower = colorless. ·         The lower phase was taken, weight of result = 10,99 g.

2.      Reaction

       R₃N_(s) + C₂H₅OH   à   R₃NC₂H₃⁺OH^-_(aq)

Regeneration reaction:

                    R₃NC₂H₃⁺OH^-_(aq) + OH^-   à   R₃N_(s) + C₂H_4(aq) + H₂O_(l) + OH^-

R₃NC₂H₅⁺OH^-_(aq) + MgO_(aq)   à   R₃NC₂H₅Mg⁺_(aq) + OH^-

      R₃NC₂H₅Mg⁺_(aq)   à   R₃NC₂H₅Mg⁺_(s)

           R₃NC₂H₅Mg⁺_(s) + H₂O_(l)   à   R₃NC₂H₅MgOH_(aq) + H_2(g)

3.      Discussion

Calculation:

Mass of sample: 25 g

Mass of caffeine gotten (crystal): 10,99 g

Yield = mass of crystal / mass of sample x 100% = 10,99 / 25 x 100% = 43,96%

Based on theory:

Green tea contains less caffeine than black tea. In theory for 100 g of green tea contains 1–2 g caffeine. Caffeine crystal is transparent.

Based on experiment:

We used 25 g of green tea and we get 10,99 g of caffeine. It was not suitable with the theory, we should get 0,25-0,5 g of caffeine. It caused by our caffeine gotten was bond with chloroform. Our caffeine crystal is transparent.

Characteristic of materials:

1.      H₂O: as the universal solvent

2.      NaOH: as a strong base

3.      CH₃Cl: to extract caffeine and to form crystal, to form layer when separated

4.      MgO: to bind caffeine

G.    CONCLUSION   :

1.     In this experiment, the process of separating by continuous extraction through heat transfer, where continuous extraction is a method of separating substances or substitutions from the mixture and the same solvent is used repeatedly until the extraction process is complete.

2.    From the experiment, we got the caffeine crystal in green tea with extraction method by using soxhlet contain 43,96% from 25 g of green tea powder. It means we got 10,99 g caffeine contained in green tea. The color of caffeine crystal is transparent.

H.    ASSIGNMENT   :

1.      The function of MgO was to bind caffeine which had been soxhletized.

2.     MgO can be replaced by CaCO₃, but if MgO was used to bind caffeine, while CaCO₃ was used to urge caffeine to come out.

3.      In DNA/RNA system there are four bases which include pseudoalkaloid.

   

Cytosine                                        Guanine                                               Adenine                  

          Thymine                                                                    Uracyl

4.    Alkaloid is alkaline generally, because alkaloids are amine derivatives where amines are lewis base compounds.

5.   Qualitative caffeine level can be determined with iodometry. In indirect iodometric titration, sodium thiosulfate is used as a titrant with an indicator of starch. Sodium thiosulfate will react with a solution of iodine produced by the reaction between the analyze and excess KI solution. The starch indicator should be added when the titration approaches the equivalent point because starch can form a stable complex with iodine.

I.       REFERENCES  :

Pavia, D. L., Lampman, G. M., Kriz, G. S., Engel, R. G., 2010, A Small Scale Approach to Organic Laboratory Techniques Third Edition, Cengange Learning: Asia

Pradeep, S., Rameshaiah, G. N., Ashoka, H., 2015, Caffeine Extraction and Characterization, International Journal of Current Research and Review, 7(9): 16-19

Rebecca, L. J., Seshiah, C., Tissopi, T., 2014, Extraction of Caffeine from Used Tea Leaves, The Annals of “Valahia” University of Targoviste