FINAL EXAM

NIM : RSA1C110013
Name : Choirunnisa Mayara

UJIAN AKHIR SEMESTER

MATA KULIAH       : KIMIA BAHAN ALAM

SKS                             : 2

DOSEN                      : Dr. Syamsurizal, M.Si

WAKTU                     : 22-29 Desember 2012

PETUNJUK : Ujian ini open book. Tapi tidak diizinkan mencontek, bilamana ditemukan, maka anda dinyatakan GAGAL. Jawaban anda diposting di bolg masing-masing.

1. Explain the triterpenoid biosynthetic pathway, identify important factors that determine the quantities produced many triterpenoids.

Answer:
Terpenoids are built up from C5 units, isopentenyl diphosphate (IPP). IPP is supplied from the cytosolic mevalonic acid (MVA) pathway and the plastidal methylerythritol phosphate (MEP) pathway. Triterpenoids and sesquiterpenoids are biosynthesized via the MVA pathway, whereas monoterpenoids, diterpenoid, and tetraterpenoids are biosynthesized via the MEP pathway. The first diversifying step in triterpenoid biosynthesis is the cyclization of 2,3-oxidosqualene catalyzed by oxidosqualene cyclase. Triterpenoid biosynthesis starts from mevalonic pathway, reacts with IPP generating DMPP. DMPP react with IPP, GPP formed reacted again with IPP, FPP formed. Reaksikan with FPP FPP at a later formed skualena. Skualena undergo cyclization that would eventually form triterpenoid compounds.
the factors that most influence is cyclic in skualena.

2. Describe the structure determination of flavonoids, specificity and intensity of absorption signal by using IR and NMR spectra. Give the example of at least two different structures!

answer :
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy, is a research technique that exploits the magnetic properties of certain atomic nuclei to determine physical and chemical properties of atoms or the molecules in which they are contained. It relies on the phenomenon of nuclear magnetic resonance and can provide detailed information about the structure, dynamics, reaction state, and chemical environment of molecules.

Most frequently, NMR spectroscopy is used by chemists and biochemists to investigate the properties of organic molecules, though it is applicable to any kind of sample that contains nuclei possessing spin. Suitable samples range from small compounds analyzed with 1-dimensional proton or carbon-13 NMR spectroscopy to large proteins or nucleic acids using 3 or 4-dimensional techniques. The impact of NMR spectroscopy on the sciences has been substantial because of the range of information and the diversity of samples, including solutions and solids.

Infrared spectroscopy (IR spectroscopy) is the spectroscopy that deals with the infrared region of the electromagnetic spectrum, that is light with a longer wavelength and lower frequency than visible light. It covers a range of techniques, mostly based on absorption spectroscopy. As with all spectroscopic techniques, it can be used to identify and study chemicals. A common laboratory instrument that uses this technique is a Fourier transform infrared (FTIR) spectrometer.

The infrared portion of the electromagnetic spectrum is usually divided into three regions; the near-, mid- and far- infrared, named for their relation to the visible spectrum. The higher-energy near-IR, approximately 14000–4000 cm−1 (0.8–2.5 μm wavelength) can excite overtone or harmonic vibrations. The mid-infrared, approximately 4000–400 cm−1 (2.5–25 μm) may be used to study the fundamental vibrations and associated rotational-vibrational structure. The far-infrared, approximately 400–10 cm−1 (25–1000 μm), lying adjacent to the microwave region, has low energy and may be used for rotational spectroscopy. The names and classifications of these subregions are conventions, and are only loosely based on the relative molecular or electromagnetic properties.

3. In the isolation of alkaloids, in the early stages of acid or base required conditions. Explain the basis of the use of reagents, and give examples of at least three kinds of alkaloids.

answer:
Alkaloid needs acid condition to produces salts. Alkaloid salts already in base form would then be withdrawn by organic solvents. For example, in the isolation of caffeine, caffeine in the aqueous phase was extracted with chloroform as in acid solubility of caffeine in chloroform greater solubility in water. Similarly, in the isolation of nicotine, the addition of 10% sulfuric acid in the solution aims to be a solution in acid, because the caffeine extraction using ethanol a more optimal under acidic conditions. Nicotine and morphine to the same treatment results are the same.

4. Describe the relationship between biosynthesis, methods of isolation and structural determination of compounds of natural ingredients. Give an example.

answer:
Biosynthesis, isolation and structure determination are closely related to each other. Synthesis and purification of the material is not the final goal for chemists. That must be defined is the structure of the material has been synthesized and purified. before the determination of the structure, we must first know its biosynthesis process. of the biosynthesis of these compounds, we'll get step-by-step formation of the compound, the compound reacts with what, and what are the factors that influence it. of biosynthesis we will also know the properties of natural materials such compounds, so we can design an isolation method based on the nature and possible reactions to extract them how to manufacture the compound. manufacture in the lab will be successful if we use the appropriate tools and materials, solvents, indicators, temperature also affects the success of the experiment. after isolation, then we can identify the compound. This stage is the stage that Palin difficult. It must be recognized that until the latter half of the 20th century, chemists are not equipped with enough tools to overcome this difficulty. Some chemists proposed structure is not appropriate even for a few years. However, the situation changed drastically since developed various spectroscopic techniques such as NMR, IR, UV, and others. NMR (Nuclear Magnetic Resonance) method in particular is highly superior to other methods. For crystalline solids, X-ray crystallographic analysis proved to be very useful.When the physical and chemical properties of the investigated compounds are not appropriate with any compound that are well known in the literature, the possibility of this compound is a new compound, has never been synthesized or has not been reported.

Cholesterol

Isolation of Cholesterol

This experiment uses egg yolk samples. Isolation of cholesterol begins with the addition of a solution of ethanol and ether with perbandungan 2: 1. Ethanol tends to be polar and nonpolar ether which tends to be a combination of solvent can dissolve the phospholipids that are ampifatik, cholesterol, and triglyceride levels in the egg yolk. Then do the filtration to separate the fat dissolved in ether and ethanol with other components such as pigments (lutein and astaxantin) and protein. The resulting filtrate is colorless (clear) and a yellow precipitate. This is consistent with the theory Gunawan (2009) as described in the literature.

Precipitated and then rinsed with hexane to dissolve the lipid component extracted did not participate in the early stages. Hexane is an excellent solvent for extracting neutral lipid components. Furthermore, the results of the extract is poured into a separating funnel and allowed to stand for ± 30 minutes to separate the components are soluble in hexane fats (triglycerides) with fat-soluble components elarut ethanol-ether (cholesterol and phospholipids). Hexane solvent will be at the top of the funnel, while ethanol-ether will be at the bottom of the funnel. This is due to a lower density than ethanol hexane-ether. (Palacios and Wang, 2005)

The next stage is the heating. Warming aims to evaporate the organic solvent so that only leaves the fat component. This can happen because the solvent boiling point lower than the boiling point of the fat. Further cold acetone added to the heating components that dissolve fat, which is alcohol. White precipitate formed which is a phospholipid / lecithin. This is consistent with the theory Szuhaj (1989) described in the literature.

Salkowski test conducted on the final filtrate produces red ring between the two layers. These results suggest that the positive yolk contains cholesterol.

Nicotine

Isolation of Nicotine

You will need litmus paper, acid (such as "muriatic" [hydrochloric] or sulfuric), base (lye is good), and a nonpolar solvent (benzene, toluene, or xylene are all good.)
This is a simple acid/base extraction that is pretty standard for alkaloids (of which nicotine is one.) It will yield pure crystal nicotine HCl. If you use sulfuric acid then you will get nicotine sulfate. Both are salts of nicotine and are pharmacologically similar. The average cigarette contains 1 milligram of nicotine, so keep that in mind when dosing your final product with crystal. Nicotine is a very potent drug! It only takes a few milligrams to make someone sick.
Here it is:

1) Take tobacco and mix it with distilled water. Make the tobacco water acidic to litmus paper (only a few drops of HCl needed.) Pour off the water and save it. Repeat this two or three more times, until the water is not so dark. Combine all of the water extract. Now the acidic (protonated) form of nicotine is in the water. There is also a lot of other crap there, too.

2) Add lye-water dropwise to the acidic tobacco water until the water is alkaline to litmus.

3) Add about a half volume of nonpolar solvent (benzene, toluene, xylene) to the alkaline water and gently mix. If they are mixed vigorously you will get an emulsion, which is a nightmare to separate if you don't have a centrifuge. Anyway, mix gently, such as slowly inverting the mixture in a closed bottle repeatedly. As long as two distinct layers are forming when the bubbles settle down you are in business. Pour off the top layer (the solvent.) Repeat this two more times. Combine the solvent. Now the free base nicotine is in the solvent and is relatively pure. But we need the salt of nicotine, not the free base.

4) Take about 2 volumes of distilled water and make them acidic by dropwise addition of acid. Use this water to extract out the nicotine from the solvent. By mixing the water with the solvent in the same manner described above the nicotine will now dissolve preferentially into the water. Extract out the nicotine with the acidic water 3 times. Combine the water. Now (slowly!) add dropwise lye water until the pH is neutral (7). Evaporate the water. The yellow crystals left behind are pure nicotine HCl. Protect them from light when storing as nicotine is photosensitive. Have fun!   "

Also you may try reading "Assorted Nasties" by David Harber which is a step by step cookbook method for extracting nicotine.

MID TEST OF CHEMICAL NATURAL PRODUCTS

NAME : CHOIRUNNISA MAYARA
NIM     : RSA1C110013

   1.  How to convert a compound of natural ingredients that do not have the potential (inactive) can be made into superior compounds that have a high potential for biological activity. Give the example.

Answer:

The way to convert a compound of natural ingredients that do not have the potential (inactive) can be made into superior compounds that have a high potential for biological activity with try it out one on one, tested with a given treatment, and activates its functional groups.

One example of the compound is glikolat acid. Bile acids are synthesized from cholesterol. Produced the first compound is 7-hidroksikolesterol, after several reaction steps into cholic acid. This last compound has been activated by KoASH and then reacts with glycine changed to glikolat acid

   2.  Explain how the idea of a compound of natural ingredients that have a high biological potency and prospective for the benefit of sentient beings can be synthesized in the laboratory.

Answer:

To using natural products in laboratory, we have to extract the compounds first.

It can be extracted from plant with method:

-          Distillation of water vapor : water vapor distillation of water intended for quote containing crude oil evaporates or contain chemical components that have a high boiling point at normal atmospheric pressure. In this method steam is used to sum ​​up the bulbs and a small heating the water vapor evaporates back together oil evaporated and condensed by the condenser to form the molecules of liquid drip into the funnel reservoir filled with water.

-          Solvent extraction : solvent extraction, also known as water extraction is the best method of separation and popular. The main reason is the separation can be done either in a macro or micro level. The principle of this method is based on the distribution of the solvent with a certain ratio between the two are not mutually mixed solvents, such as benzene, carbon tetrachloride or chloroform. Its limitation is the solute can be transferred to the number berbada in both phases of solvent.

-          Fat adsorption : Adsorption is a process that occurs when a fluid, liquid or gas, is bound to a solid or liquid and eventually form a thin layer or film on its surface. In contrast to an absorption of fluid absorption by other fluids by forming a solution.

   3.  Explain the basic rules in choosing a solvent for the isolation and purification of a compound of natural ingredients. Give the example for 4 classes of compounds of natural products: terpenoids, alkaloids, flavonoids, and steroids.

Answer:

Things to consider in the process of extraction is a compound that has the same polarity will be easier interested / dissolved by the solvent that has the same polarity. Related to the polarity of the solvent, there are three classes of solvents, namely:

- Polar solvents

Having a high level of polarity, suitable to extract polar compounds from plants. Polar solvents tend to be universally used because normally though polar, can still quote the compounds with lower levels of polarity. One example is the polar solvents: water, methanol, ethanol, acetic acid.

- Solvent semipolar

Semipolar solvent polarity has a lower rate than the polar solvent. Is a good solvent for semipolar compounds from plants. Examples of these solvents are: acetone, ethyl acetate, chloroform

- Nonpolar solvents

Nonpolar solvents, almost completely polar. Is a good solvent to extract the compounds did not dissolve in polar solvents. The compound is better to extract different types of oils. Example: hexane, ether

Things that should be considered in selecting the solvent is selectivity, solvent properties, the ability to extract, non-toxic, easily vaporized, and relatively easy to obtain.

   4.  Explain the basic starting point for the determination of the structure of an organic compound. eg compounds of natural ingredients is caffeine. Put forward your ideas subject matter whatever is needed to determine the overall structure

Answer:

The structure of an organic compounds can be determined with spectroscopy. There are several types of spectroscopy including:

a. Emission spectroscopy

Emission spectroscopy using a range of the electromagnetic spectrum in which a substance radiates (emits). The substance first must absorb energy. This energy can come from various sources, which specifies the name of the next emission, like luminescence. Molecular luminescence techniques include spectrofluorimetry.

b. Spectroscopies absorption

Absorption spectroscopy is a technique in which a beam of light power was measured before and after passing through a material in this technique there is the phenomenon of light absorption.

c. NMR Spectroscopy

Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy, is the name given to the technique which exploits the magnetic properties of certain nuclei. When placed in a magnetic field, NMR active nuclei (such as 1 H or 13 C) absorb the frequency characteristics of the isotope. The resonant frequency, energy absorption and the signal intensity is proportional to the strength of the magnetic field. For example, in 21 tesla magnetic field, protons resonate at a frequency of 900 MHz. It is common to refer to the 21 T magnet as a 900 MHz magnet, although different nuclei resonate at different frequencies at this field strength. In the core of the earth's magnetic field resonates at the same frequency audio. This effect is used in the Earth's field NMR spectrometers and other instruments. Because these instruments are portable and inexpensive, they are often used to teach and study the field.

d. Infrared Spectroscopy

Infrared spectroscopy is one of the many tools used to identify compounds, both natural and artificial. In the field of physics of materials, such as polymeric materials, infrared is also used to characterize the sample. One obstacle that makes it difficult to identify compounds with infrared is the absence of standard rules to interpret the spectrum. Because of the complexity of interactions in the vibrations of molecules in a compound and external effects that are often difficult to control are no longer appropriate theoretical predictions. Knowledge in this case largely empirically derived and experience.

Near infrared spectroscopy (IMD) based on the effects of molecular overtone and combination vibrations. Two transition effects "forbidden" in the rules of the ban on quantum mechanics. As a result, the molar absorptivity in the near infrared region is quite small.

In caffeine, the structure can be determined with infrared spectroscopy, the typical absorption data from multiple functional groups, or by comparison with a standard IR spectrum of caffeine. From the results of spectroscopic compound then can be structured through a cluster-Sugus functions contained therein. Another method to determine the structure through mixed melting point test, the use of derivatives solids, comparison of physical properties, as well as qualitative reactions.

TERPENOIDS

TERPENOID

Terpenoids are widely distributed and are found in higher plants. Terpenoids produced by fungi, marine organisms, and insects, and plants. Terpenoids is defined as the natural product structure is divided into a number of isoprene units, as it is also called the isoprenoid compounds (C5H8). Isoprene units prepared on asaetat through mevalonic acid pathway and is associated with a carbon chain containing two unsaturated bonds.

During the preparation of terpenoids, two isoprene units condenses between the head and tail. Terpenoids are composed of two classes of monoterpenoid compound isoprene form (C10H16). Sesquiterpenes (C15H24) is composed of 3 units of isoprene, diterpenoid (C20H32) is composed of 4 units of isoprene, sesterpen (C25H40) is composed of five isoprene, triterpenoids (C30H42) is made up of 6 units of isoprene, and tetraterpen (C40H64) is composed of eight isoprene.

Biosynthesis of Terpenoids

Biosynthesis by incorporation of 3 acetyl-CoA via 2 stages into (3S)-3-hydroxyl-3-methyl-glutaril-CoA (HMG-CoA). Furthermore, the reduction occurred HMG-CoA into (3R) mevalonic acid, then going decarboxylation to form isopentenilpirpphosphate (IPP) C5 form terpenoids such as isoprene in the active form. IPP isomerization to 3,3 dimethyl allyl pyrophosphate and then condensing the head and tail. 2 molecules of C5 by phenyl transferase transformed into Geranyl pyrophosphate (C10) or GPP. GPP as substrate monoterpenoid synthesis and biosynthesis of monoterpenoid precursors.

MONOTERPENOID

It has been known for more than 100 terpenoids produced naturally, many of which have been isolated from higher plants. Monoterpenoid found in a number of marine organisms, insects, and plants. Typical properties of monoterpenoid is volatile and distinctive smell. These compounds are found mainly in plants that have a distinctive smell, so banak used sebgai kompnen of perfumes and oils evaporate in produksid and the food industry as a flavor enhancer.

Monoterpenoid been classified into 35 different types of structures. Type of structure is most common adlah myrcane acyclic, monocyclic p-menthane, and bicyclic bornane, cirane, tenchane, pinane, and thujan. While many monoterpenoid derivatives of this class occurs naturally in its pure form in some plants, both enantiomers may be found. Case of (+) and (-)-alpha-pinene found in all kinds of pine.
Biosynthesis of monoterpenes starting a small lane which leads to another on the acyclic isoprenoid, intermediate C10 Geranyl Phosphate. Furthermore formed Farnesil Pyrophosphate (C15).

classification based on the n value.

Nama	Rumus	Sumber
Monoterpen	C10H16	Minyak Atsiri
Seskuiterpen	C15H24	Minyak Atsiri
Diterpen	C20H32	Resin Pinus
Triterpen	C30H48	Saponin, Damar
Tetraterpen	C40H64	Pigmen, Karoten
Politerpen	(C5H8)n  n  8	Karet Alam

one example of terpenoids is karet alam that contains politerpen.

Biosynthesis of Flavanon

Flavanones, a direct precursor to the most flavonoids, synthesized from the amino acid phenylalanine or tyrosine. The process begins with the enzyme phenylalanine / tyrosine ammonia lyase (PAL / TAL), change buillding block of amino acids into phenyl-propanoic acid. Biosynthetic pathway involving the enzyme flavanones, cytochrome-P450, cinnamate 4-hydroxylase (C4H), by adding 4'-hydroxyl group of the aromatic ring of phenylalanine. The next CoA esters synthesized from phenylpropanoic acids with the help of enzymes phenylpropanoyl-CoA ligases, such as 4 - coumaryl: CoA ligase (4CL). Type III polyketide synthase Chalcone synthase (CHS) then catalyzes the sequential condensation of three malonyl-CoA CoA-ester with 1 form chalcones. This is the step that produces flavonoid biosynthesi.

 First, there is an alternative pathway enzymes type III polyketide synthases that have high homology with CHS (> 70%) using the same precursor form stilbenes (using 3 units of malonyl-CoA), benzylacetolactone (only use 1 unit malonyl-CoA), and other aromatic molecules.

Flavanones final structure is formed only if diisomerisasi chalcones into (2S)-flavanone by Chalcone isomerase (CHI), this reaction occurs spontaneously at alkaline conditions. Once formed flavanones, a lot of compound enzymes could alter the functional group or alter the conformation of the 3-ring core fenilpropan produces up to 8000 different compounds structure.Functionalization can be hydroxylation, reduction, alkylation, oxidation, and glukosilasi, each alone or in combination. By nature, these enzymes exist in plants, but according to reports Ueda et al. that there is a type III polyketide synthases derived from microorganisms. This information is essential for the production of compounds flavanones in scale bioreactor.

The addition of consecutive carbon atoms of malonyl-CoA by CHS are shown in green, red, and blue. R group showed hydroxylation patterns on natural flavonoid unnatural although substitutions can occur in this position. Abbreviations: DFR dihydroflavanone reductase, reductase leucoanthocynanidin LAR, ANS anthocyanidin synthase, 3GT uridine, flavanone 3-glucoside transferase, FSI flanone synthase, CHR Chalcone reductase, IFS isoflavanone synthase, flavanone hydroxytransferase FHT, FLS flavonol synthase.

Flavonoids

Flavonoids (or bioflavonoids) (from the Latin word flavus meaning yellow, their colour in nature) are a class of plant secondary metabolites.
Flavonoids were referred to as Vitamin P (probably due to the effect they had on the permeability of vascular capillaries) from the mid-1930s to early 50s, but the term has since fallen out of use.

Flavonoids (or bioflavonoids) (from the Latin word flavus meaning yellow, their colour in nature) are a class of plant secondary metabolites.
Flavonoids were referred to as Vitamin P (probably due to the effect they had on the permeability of vascular capillaries) from the mid-1930s to early 50s, but the term has since fallen out of use.

Flavonoids (or bioflavonoids), also collectively known as Vitamin P and citrin, are a class of plant secondary metabolites. According to the IUPAC nomenclature, they can be classified into:

• ''flavonoids'', derived from 2-phenylchromen-4-one (2-phenyl-1,4-benzopyrone) structure (examples: quercetin, rutin).
• ''isoflavonoids'', derived from 3-phenylchromen-4-one (3-phenyl-1,4-benzopyrone) structure
• ''neoflavonoids'', derived from 4-phenylcoumarine (4-phenyl-1,2-benzopyrone) structure.

The three flavonoid classes above are all ketone-containing compounds, and as such, are flavonoids and flavonols. This class was the first to be termed "bioflavonoids." The terms flavonoid and bioflavonoid have also been more loosely used to describe non-ketone polyhydroxy polyphenol compounds which are more specifically termed flavanoids, flavan-3-ols, or catechins (although catechins are actually a subgroup of flavanoids).

Flavonoids are widely distributed in plants fulfilling many functions.

Flavonoids are the most important plant pigments for flower coloration producing yellow or red/blue pigmentation in petals designed to attract pollinator animals.

Flavonoids secreted by the root of their host plant help ''Rhizobia'' in the infection stage of their symbiotic relationship with legumes like peas, beans, clover, and soy. Rhizobia living in soil are able to sense the flavonoids and this triggers the secretion of Nod factors, which in turn are recognized by the host plant and can lead to root hair deformation and several cellular responses such as ion fluxes and the formation of a root nodule.

They also protect plants from attacks by microbes, fungi and insects.

Flavonoids (specifically flavanoids such as the catechins) are "the most common group of polyphenolic compounds in the human diet and are found ubiquitously in plants". Flavonols, the original bioflavonoids such as quercetin, are also found ubiquitously, but in lesser quantities. Both sets of compounds have evidence of health-modulating effects in animals which eat them.

The widespread distribution of flavonoids, their variety and their relatively low toxicity compared to other active plant compounds (for instance alkaloids) mean that many animals, including humans, ingest significant quantities in their diet. Resulting from experimental evidence that they may modify allergens, viruses, and carcinogens, flavonoids have potential to be biological "response modifiers", such as anti-allergic, anti-inflammatory, anti-microbial and anti-cancer activities shown from in vitro studies.

Antioxidant activity in vitro

Flavonoids (both flavonols and flavanols) are most commonly known for their antioxidant activity in vitro.

Consumers and food manufacturers have become interested in flavonoids for their possible medicinal properties, especially their putative role in prevention of cancers and cardiovascular diseases. Although physiological evidence is not yet established, the beneficial effects of fruits, vegetables, and tea or even red wine have sometimes been attributed to flavonoid compounds rather than to known micronutrients, such as vitamins and dietary minerals.

Alternatively, research conducted at the Linus Pauling Institute and evaluated by the European Food Safety Authority indicates that, following dietary intake, flavonoids themselves are of little or no direct antioxidant value. As body conditions are unlike controlled test tube conditions, flavonoids and other polyphenols are poorly absorbed (less than 5%), with most of what is absorbed being quickly metabolized and excreted.

The increase in antioxidant capacity of blood seen after the consumption of flavonoid-rich foods is not caused directly by flavonoids themselves, but most likely is due to increased uric acid levels that result from metabolism of flavonoids. According to Frei, "we can now follow the activity of flavonoids in the body, and one thing that is clear is that the body sees them as foreign compounds and is trying to get rid of them."

Other potential health benefits

Cancer

Physiological processing of unwanted flavonoid compounds induces so-called Phase II enzymes that also help to eliminate mutagens and carcinogens, and therefore may be of value in cancer prevention. Flavonoids could also induce mechanisms that may kill cancer cells and inhibit tumor invasion.

Research also indicated that only small amounts of flavonoids may be needed for possible benefits. Taking large dietary supplements likely provides no extra benefit and may pose risks. However, certainty of neither a benefit nor a risk has been proven yet in large-scale human intervention trials.

Capillary stabilizing agents

Bioflavonoids like rutin, monoxerutin, diosmin, troxerutin and hidrosmin have potential vasoprotective proprieties still under experimental evaluation.

PROBLEM :
I'm looking for a flavonoid extraction and i dont find any exact one.
how to exact flavonoids, the process, and i heard something about i can extract it from the orange or any other fruit.