Amino acids are the building blocks of proteins. All amino acids have the same basic structure but differ in their R-side chains. Each amino acid consists of an amino group (-NH3), a carboxyl group (-COOH) and a hydrogen atom (H). The amino and carboxyl groups are attached to a central alpha carbon together with a hydrogen atom and an R-side chain. There are currently known that over 170 amino acids occur in organisms but only 20 are commonly found in proteins.
All the test tubes contained in total 3 mL of solution. The following solutions’ concentrations in a tube were .1 mL of dye and 2.9 mL of water, .25 mL of dye and 2.75 mL of water, .5 mL of dye and 2.5 mL of water, 1.0 mL of dye and 2.0 mL of water, 2.0 mL of dye and 1.0 mL of water, and 3.0 mL of dye and 0 mL of water. These samples were tested by the spectrophotometer, and the absorbencies recorded. This whole process was completed twice and the absorbencies were averaged. Lastly, final concentrations and dilution factors were calculated by using the appropriate formulas.
This method has been specially valuable for the separation of closely related amino acids. The mixture is dissolved in a fluid called mobile phase , which carries it through the structure holding another material called the stationary phase . The various amino acids travel at different speed , causing them to separate based on its R group . Amino acid Amino acid play central roles as building blocks of proteins and as intermediates in metabolisms . The 20 amino acids are found within proteins convey a vast array of chemical versatility (The Biology Project.2000).All amino acids found in proteins have a basic structure , different only in the structure of the R group or the side chain(Figure).
Next, a basic stock solution was used to prepare various concentrations ranging from 1.0 x 10-8M to 1.0 x 10-1M by serial dilution. The tissue was washed by overflow with reservoir’s solution for 5 seconds to obtain baseline before adding 0.1ml, 0.3ml and 0.5ml for each concentration respectively into the tissue bath.The tissue’s peak response for each final bath concentration(FBC) was measured and recorded. Rmax and EC50 of histamine were recorded. Later, 5ml of 1 x 10-6 M of mepyramine was added into the reservoir containing 1000ml of Krebs-Henssleit solution to produce a FBC of 5.0 x 10-9M. It was equilibrated with tissue for 10 minutes by flushing into the organ bath.
In the round-bottom flask (100 mL), we placed p-aminobenzoic acid (1.2 g) and ethanol (12 mL). We swirled the mixture until the solid dissolved completely. We used Pasteur pipet to add concentrated sulfuric acid (1.0 mL) to the flask. We added boiling stone and assembled the reflux. Then, we did reflux for 75 minutes.
• Injection volume: 20μl • Injection concentration: 1mg /ml • Detection wavelength: 280nm 2.3.6-Isolation and purification of Flavonoids (Genistien, Rutin, Quercetin) by: 2.3.6.1- Preparative TLC plate: Isolation and purification of genistein,rutin, quercetin were carried out by preparative TLC. On a glass plates (20 cm x20 cm) a slurry of 60 gm of silica gel GF 254 suspended in 120 ml of distilled water was applied in 0.75 mm thickness manually by using Jobling laboratory division plate coater. The freshly coated plates were left until the transparency of the layer disappears. After 10 minutes, the plates heated for 1 hour at 110ºC. The completely dried and activated plates are kept in a dry place for use.
Other amide types include RC(O)NHR and RNH2. Amides are found in a wide variety of things, they are used in the production of drugs such as paracetamol and LSD, but are also found in DNA. Amides are similar to amines (RNH2) in that they are both derivatives of ammonia and are both bases, though amides are considerably weak when compared to amines (amines have a pKa of around 9.5, while amides have a pKa of around -0.5). Therefore amides do not have clearly noticeable acid-base properties in water. The lack of basicity within amide is due to the C=O, or carbonyl group, within the amide as it has electron withdrawing properties causing the lone pair of electrons within nitrogen to become delocalised.
The incubation mixture contained 2.5 ml of 1.2% (w/v) fibrin, 2.5 ml of 100 mM Tris–HCl buffer, 10 mM CaCl2 (pH 7.8), and 20 µg of enzyme. The incubation was carried out at 37°C for 30 min, and the reaction was stopped by adding 5 ml of 110 mM trichloroacetic acid containing 220 mM sodium acetate and 330 mM acetic acid. This reaction mixture was centrifuged at 3,000×g for 5 min, and the absorbance of the trichloroacetic acid (50 mM) soluble product was determined at 275 nm. One unit of fibrinolytic enzyme activity was defined as the amount of enzyme required to liberate 1 µg of L-tyrosine per minute at 37°C. The total protein determination was performed as described by Lowry et al.
During this step, I observed that there were bubbles in the solution, especially at the bottom of the beaker. After adding the HLC, there solution had a slight yellow tint. Next, I mixed 0.529g of sodium acetate in 3mL of water and added 0.679g of acetic anhydride to the aniline solution and immediately added sodium acetate. The solution was cooled in an ice bath for fifteen minutes. During this time, I noticed the formation
Grade) in 1 l water, standardize this solution with 0.0192(N) silver nitrate solution. The solution losses strength gradually and must be rechecked every week. 1 ml of solution = 1 mg CN (ix) Standard cyanide solution: Dilute 10 ml stock cyanide solution to 1 litre with distilled water, mix and make a second dilution of 10 ml to 100 ml. Prepare fresh solution daily. 1 ml = 1 µg CN (x) Chloramine –T: Dissolve 1 gm chloramine – T in 100 ml distilled water.