FINAL EXAMINATION (NATURAL PRODUCT CHEMISTRY)

Name : Saely Natalia Sinaga
NIM : A1C109040

1.      

1   1. . Generally are solid while the oil is liquid phase, however both are equally trglyceride. Explain why the form of two different trglyceride, and point out important factors that determine the form of fat

      
     Answer : 


    Triglycerides in the fat oil

Can be either solid or liquid depending on the composition of the constituent fatty acids. Liquid vegetable oil because it contains unsaturated fatty acids, while animal fats are generally solid at room temperature because it contains unsaturated fatty acids.

    Fat oil

Triglycerides are composed of a mixture of esters of glycerol and long chain fatty acids. Fat if the oil will produce three molecular hydrolyzed long-chain fatty acids and a glycerol molecule.

    Triglycerides oil fatty

Derived from various sources have physico-chemical properties are different from each other that occurs because of differences in the number and types of esters contained therein.

    Triglycerides in the fat oil

Did not differ in their chemical composition differing only in shape or form. Triglycerides are called oils when melted at room temperature and is called solid if it freezes at room temperature.

There are many different kinds of fats, but each is a variation on the same chemical structure. All fats are derivatives of fatty acids and glycerol. The molecules are called triglycerides, which are triesters of glycerol (an ester being the molecule formed from the reaction of the carboxylic acid and an organic alcohol). As a simple visual illustration, if the kinks and angles of these chains were straightened out, the molecule would have the shape of a capital letter E. The fatty acids would each be a horizontal line; the glycerol "backbone" would be the vertical line that joins the horizontal lines. Fats therefore have "ester" bonds.

The properties of any specific fat molecule depend on the particular fatty acids that constitute it. Different fatty acids are composed of different numbers of carbon and hydrogen atoms. The carbon atoms, each bonded to two neighboring carbon atoms, form a zigzagging chain; the more carbon atoms there are in any fatty acid, the longer its chain will be. Fatty acids with long chains are more susceptible to intermolecular forces of attraction (in this case, van der Waals forces), raising its melting point. Long chains also yield more energy per molecule when metabolized.

   Saturated and unsaturated fats

A fat's constituent fatty acids may also differ in the C/H ratio. When all three fatty acids have the formula C_nH_(2n+1)CO₂H, the resulting fat is called "saturated". Values of n usually range from 13 to 17. Each carbon atom in the chain is saturated with hydrogen, meaning they are bonded to as many hydrogens as possible. Unsaturated fats are derived from fatty acids with the formula C_nH_(2n-1)CO₂H. These fatty acids contain double bonds within carbon chain. This results in an "unsaturated" fatty acid. More specifically, it would be amonounsaturated fatty acid. Polyunsaturated fatty acids would be fatty acids with more than one double bond; they have the formula, C_nH_(2n-3)CO₂H and C_nH_(2n-5)CO₂H. Unsaturated fats can be converted to saturated ones by the process of hydrogenation. This technology underpinned the development of margerine.

Saturated and unsaturated fats differ in their energy content and melting point. Since unsaturated fats contain fewer carbon-hydrogen bonds than saturated fats with the same number of carbon atoms, unsaturated fats will yield slightly less energy during metabolism than saturated fats with the same number of carbon atoms. Saturated fats can stack themselves in a closely packed arrangement, so they can freeze easily and are typically solid at room temperature. For example, animal fats tallow and lard are high in saturated fatty acid content and are solids. Olive and linseed oils on the other hand are highly unsaturated and are oily.

   Trans fats

There are two ways the double bond may be arranged: the isomer with both parts of the chain on the same side of the double bond (thecis-isomer), or the isomer with the parts of the chain on opposite sides of the double bond (the trans-isomer). Most trans-isomer fats (commonly called trans fats) are commercially produced. Trans fatty acids are rare in nature. The cis-isomer introduces a kink into the molecule that prevents the fats from stacking efficiently as in the case of fats with saturated chains. This decreases intermolecular forces between the fat molecules, making it more difficult for unsaturated cis-fats to freeze; they are typically liquid at room temperature. Trans fats may still stack like saturated fats, and are not as susceptible to metabolization as other fats. Trans fats may significantly increase the risk of coronary heart disease.

2. How a primary metabolite can ber converted into secondary metabolites. What is the basic idea and how the mechanism could describe

Answer: 


The basic idea a primary can be converted into secondary metabolites is The Building Block. The building blocks for secondary metabolites are derived from primary metabolism.The number of building blocks needed is surprisingly few. The most important building blocks employed in the biosynthesis of secondary metabolites are derived from:

1.Acetyl coenzyme A (acetyl-CoA)

2.Shikimic acid

3.Mevalonic acid

4.1-deoxyxylulose-5-phosphate

5.Amino acids

The Mechanism secondary metabolite, we can see in the bottom

3.  Hormone progesterone is essential for the survival of the pregnancy. These hormones are derived from a steroid biogenetically. Explain the logic of chemical reactions which may occur in the formation of progesterone

Answer : The Biosynthesis Progesterone


In mammals, progesterone , like all other steroid hormones, is synthesized frompregnenolone , which in turn is derived from cholesterol

Cholesterol  undergoes double oxidation to produce 20,22-dihydroxycholesterol . This vicinal diol is then further oxidized with loss of the side chain starting at position C-22 to produce pregnenolone . This reaction is catalyzed by cytochrome P450scc. The conversion of pregnenolone to progesterone takes place in two steps. First, the 3-hydroxyl group is oxidized to a keto group and second, the double bond is moved to C-4, from C-5 through a keto/enol tautomerization reaction.This reaction is catalyzed by 3beta-hydroxysteroid dehydrogenase/delta(5)-delta(4)isomerase.

Progesterone in turn (see lower half of figure to the right) is the precursor of the mineralocorticoid aldosterone, and after conversion to 17-hydroxyprogesterone (another natural progestogen) of cortisol and androstenedione. Androstenedione can be converted totestosterone, estrone and estradiol.

Pregenolone and progesterone can also be synthesized by yeast.

     4.       Many alkaloids are toxic to other organism. They often have pharmacological effects and are used as medications, are recreational drugs, or in entheogenic rituals. Describe in outline the process if biosynthesis of an alkaloid coumpound and describe the function groups which play an important role in the biological activities

Answer: 

One of alkaloid is toxic to organism is Nicotine

Nicotine, a plant defense alkaloid, is a pale yellow to dark brown liquid with a slight, fishy odor when warm.  Biologically, production of nicotine requires nicotinic acid (aka vitamin B3 or niacin) and an N-methyl-pyrrolinium cation, which is derived from ornithine (a non-protein amino acid derived from Krebs cycle intermediates) (1). (Figure 1)

Figure 1:  Synthesis of nicotine from nicotinic acid and ornithine precursors.

Laboratory Synthesis Of Nicotine