Structure and Function of Lipids in Plants and Animals
Lipids are the name given to a mixed group of organic compounds. The
elements Hydrogen, Oxygen and Carbon are always found in Lipids. The
difference between them and Carbohydrates is that they have a lower
proportion of Oxygen in the molecule. Lipids are insoluble in water,
but they are soluble in organic solvents, such as ether, acetone,
chloroform or benzene.
There are several parts in the group of Lipids:
o fats and oils,
o waxes,
o phospholipids,
o steroids (like cholesterol, oestrogen and testosterone), and some
other related compounds.
At room temperature, fats are solids and oils are liquids. Fats and
oils are typically found in animals and plants. Fats are of animal
origin, while oils tend to be found in plants. Fats and oils are made
up of a glycerol (a type of alcohol with a hydroxyl group on each of
its three carbons) and three fatty acids (an organic acid). Since
there are three fatty acids attached, these are known as triglycerides.
A condensation reaction produces a triglyceride and water molecule
when the glycerol and three fatty acids react together (see diagram
below). The fatty acid molecules are insoluble in water because of
their long hydrocarbon tails (the tails are referred to as hydrophobic
or “water-hating”). The head of the molecule is a carboxyl group which
is hydrophilic or “water-loving”.
[IMAGE]
Fatty acids are the main component of soap, where their tails are
soluble in oily dirt and their heads are soluble in water to emulsify
and wash away the oily dirt. However, when the head end is attached to
glycerol to form a fat, that whole molecule is hydrophobic.
The digestion of triglycerides is catalysed by lipase enzymes which
are found, for example, in the digestive system of animals and in
germinating seeds, in the lysosomes inside cells and in the secretions
of saprophytic bacteria and fungi. Triglycerides are created in fat
storage depots, in such places as, in liver cells, in the adipose
The C-H (sp3) hydrogens from our product displayed at wavelength 2959 cm-1 correlates to the methyl groups located on the ends of isopentyl acetate4. A really prominent, strong peak located at 1742 cm-1 shows that a C=O ester stretch is located in the product, along with at 1244 cm-1 the spectrum shows a strong peak representing the C(=O)-O stretch that is crucial to the structure of isopentyl acetate. Shown in my IR spectrum is a weak O-H (H-bonded) peak at 3464 cm-1 which shows that I have an impurity of isopentyl alcohol in my product. Isopentyl alcohol has similar boiling points and density as my product so the impurity could have easily boiled out with the isopentyl acetate during distillation. The isopentyl alcohol was also present in my 1H-NMR spectrum backing up the impurity peak at 3464
Esters are defined as molecules consisting of a carbonyl group which is adjacent to an ether linkage. They are polar molecules which are less polar than alcohols but more so than ethers, due to their degree of hydrogen bonding ability. Most often derived from reacting an alcohol with a carboxylic acid, esters are a unique, ubiquitous class of compounds with many useful applications in both natural and industrial processes 1. For example, within mammals, esters are used in triglycerides and other lipids as they are the main functional group attacking fatty acids to the glycerol chain 2. A unique property of esters is their tendency to give off distinct aromas such as the scent of apples (Ethyl caprylate) and bananas (Isoamyl acetate). This is of a unique importance especially in industries that utilize flavors and aromas such as the tobacco, candy and alcohol industry. Consistent research is conducted in order to enhance and increase the effectiveness of esters in these products 3.
Every 5 minutes, a small amount of mixture was dissolved in acetone (0.5 mL) and was spotted onto a thin layer chromatography (TLC) plate, which contained an eluent mixture of ethyl acetate (2 mL) and hexanes (8 mL). The bezaldehyde disappearance was monitored under an ultraviolet (UV) light. Water (10 mL) was added after the reaction was complete, and vacuum filtrated with a Buchner funnel. Cold ethanol (5 mL) was added drop-by-drop to the dried solid and stirred at room temperature for about 10 minutes. Then, the solution was removed from the stirrer and place in an ice bath until recrystallization. The recrystallized product was dried under vacuum filtration and the 0.057 g (0.22 mmol, 43%) product was analyzed via FTIR and 1H NMR
As shown in figure 2, the percentage of each isomeric alcohol in the mixture had been determined. The hydrogen atom on the carbon atom with the hydroxyl group appear at around 4.0 ppm for borneol and 3.6 ppm for isoborneol. The product ratio has been determined by integrating the peaks. A ratio of 6:1 for the Isoborneol/borneol ratio was expected and is validated by the calculations shown above, with isoborneol percentage at 83.82% and 16.17% of borneol. A CHCl3 group noted at around 7ppm and a CH2Cl2 at around 3.5ppm.
Lipid-soluble and Water-soluble hormones are products of the Endocrine gland. These hormones are transported in the body through the blood stream. However, they have different characteristics or properties that ensure their effectiveness is accomplished.
Data Table 3 indicates the observations from these tests. Though a control test for each test wasn’t prepared, due to the starting reagents being unattainable, the results clearly show that the product is unsaturated. An unsaturated compound means that there is/are bonds in its structure. The product was also analyzed by infrared spectroscopy and gas chromatography. The spectrums obtained allowed one to determine the composition of 1-methylcyclohexene; any impurities and excess products were observed as well. From the infrared spectrum, there is a little peak around 3300-3500 cm-1; this indicated a very little presence of alcohol in the product and thus, most of the alcohol has been successfully removed. If one compared the IR spectrum of the product to the starting material, 2-methylcyclohexanol, one could clearly see the change in peak size of the O-H stretch. The infrared spectrum of 1-methylcyclohexene also depicted a C-H stretch and an alkene functional group at 500-1500 cm-1 and 2932.54cm-1, respectively. From the gas chromatography spectrum (Data Table 4), the area percentages show that there were three products - peaks 22 through 24 - that were formed from the dehydration experiment. Nevertheless, there are two predominant products, as shown from their high percentages, 3-methylcyclohexene (~24%) and 1-methylcyclohexene
head group is attached to one of the glycerol hydroxyls with addition to the two hydrocarbon fatty
ester, and we produce the most acid and alcohol. In bottle 3 we still have a good
That is why ethanol was used as a solvent during this lab, because due to its structure, it has both polar and non-polar regions. Ethanol has a polar alcohol end capable of dipole-dipole interactions and hydrogen bonding, but also has a relatively non-polar CH3CH2- end with mostly London dispersion forces (LDFs). The general rule for solubility is, “like dissolves like,” meaning that polar solutes will dissolve in polar solvents and non-polar solutes will dissolve in non-polar solvents. Once extracted, performing a simple separation known as thin layer chromatography (TLC), the extract can be verified to see if it contains eugenol. TLC uses ethyl acetate (a polar solvent) in order to dissolve the molecules (also polar) in the extract. The polar solvent also contains hexane (a non-polar solvent) which allows for the polar molecules to precipitate out as small spots on the TLC plate. As shown in Figure 4, the solvent will move up the TLC plate until it reaches the spotted samples: cloves extract (Our), nutmeg extract (Oth), and 10 mg/mL eugenol standard (s). Several spots on the TLC plate show the interaction between molecules in the extract and the silica on the surface of the TLC plate. If the molecules in the extract exhibit more non-polar characteristics, they will get pulled further up the
22 CH2 units long, but it is always an even number because of the way
energy was given out or taken in. We can show this on a graph. Alcohol
Alcohol is an ethanol containing substance that is a common beverage in many social and private settings. Alcohol is also a teratogen, therefore alcohol co...
Also known as alcoholic fermentation, this process is occurs in an anaerobic environment. In alcoholic fermentation, glucose molecules are degraded into two molecules of ethanol and two molecules of carbon dioxide. In production of alcohol, first, glycolysis process will breakdown glucose molecule into to pyruvic acid. Then, carboxyl group of the pyruvic acid will be removed and causing carbon dioxide to be excreted. The NADH then left its hydrogen onto the second carbon molecule creating ethanol. The overall chemical reaction are as follows :
...icot stem. Label and sketch its parts. Take note of the position of the vascular bundle.
Alcohol is a class of organic compounds that is characterized by the presence of one or more hydroxyl groups (-OH) attached to a carbon atom. Alcohol was unknowingly produced centuries ago when fermentation occurred to crushed grapes (Pines, 1931). In today’s society alcohol is produced for the use of household products such as varnishes, cleaning products, but is more commercially important in the liquor business. A chemical process called fermentation accomplishes the production of ethanol, the alcohol or liquor. From there, the ethanol goes through distinct processes to become the dark and clear liquors on the store shelves.