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Menampilkan postingan dari November, 2013

Digitalis Purpurea

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Digitalis Purpurea (Foxglove)  is a  species  of flowering plant in the  genu s  Digitalis , in the  family   Scrophulariaceae ,  native  and widespread throughout most of  temperate  Europe. It is source of heart medicine called digitoxin. Due to the presence digitoxin, the leaves, flowers, and seeds are poisonous to human and animal if eaten. Digitoxin used to threating heart failure. Heart failure occurs when the heart unable to pump blood sufficiently to all body part. Digitoxin can resolve this problem caused by ability to promote heart beating. Digitoxin

Soredia

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Soredia are fragments of a lichen that include algal cells and fungal hyphae, they serve to disperse the lichen to new areas. It is lichen reproduction method.

Essential Oil

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Essential oil is oil excreted from plants. It also known as aetheric oil, volatile oil, or aromatic oil. Essential oil is secondary metabolit of plant used to protect its body from animal. Essential oil have low vapor point. In the room temperature it is in liquid condition and easily evaporate forming distinctive aroma.  They are used to soaps, perfumes, and cosmetics   for  flavoring  food and drink, and for adding scents to  incense  and household cleaning products. Most of essential oil did not dissolve in water and other polar solvent. As chemically, essential oil composed by many compound. Most of essetial oil including in terpenes and terpenoids and oil soluble.

Hay Test

Objective Hay Test is used to prove that bile acids reduce water surface tension. Base Theory Normal water have high surface tension that make difficult to forming misel in the gut, so our body secreted bile acids to reduce water surface tension. Activity of bile acids can help human body to transfer and absorb fats from food. It is possible to observe this by colloidal sulphur (sulphuric powder). Procedure Add 3 ml of water into two test tubes. To one of them add one drop of bile salt solution, next pour colloidal sulphur to both of them. Shake it once. In the tube with bile salt colloidal sulphur falls quickly, but in the other one, without bile salt, it stays on water surface.

Pettenkofer Test

Objective This test is used to prove the presence of bile salt. Base Theory Bile salt will reacts with hydroxymethylenephurphural to forms red solution. Hydroxymethylenephurphural is formed of sugar that dehidrated by sulphuric acid. Procedure Dissolve few crystals of saccharose in 1 ml of diluted bile salt solution. Sublayer this solution with 1 ml of concentrated H 2 SO 4  (adding sulphuric acid pouring on the wall of the tube). Red ring is formed  between both layers.

Millon Test

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Objective Millon test is chemical test to detect the presence of Tyrosine. Base Theory Millon test is given by any compound containing a phenolic hydroxy group. Consequently, any protein containing tyrosine will give a positive test of a pink to dark-red colour. The Millon reagent is a solution of mercuric and mercurous ions in nitric and nitrous acids ( CAUTION: MILLON REAGENT IS HIGHLY TOXIC AND HIGHLY CORROSIVE ). The red colour is probably due to a mercury salt of nitrated tyrosine. Procedure Place 1 mL of casein, 2% egg albumin, and 0.1 M tyrosine into separate, labelled, 12 x 75 mm test tubes. Add 3 drops of Millon’s reagent and immerse the tubes in a boiling water bath for 5 minutes. Cool the tubes and record the colours formed. Positive result of Millon Test

Ninhydrin Test

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Objective Ninhydrin reaction is chemical reaction to detect existence of amino acids. Base Theory Ninhydrin (triketohydrindene hydrate) is an oxidating agent which leads to the oxidative deamination of alpha-amino groups. It is very important for the detection and the quantitative analysis of amino acids. Ninhydrin also reacts with primary amines however the formation of carbon dioxide is quite diagnostic for amino acids. When reacting with free amines from the amino acid, blue or purple color  is produced. Most of the amino acids are hydrolyzed and reacted with ninhydrin except proline. When ninhydrin reacts with amino acids, the reaction also releases CO 2 . A ninhydrin solution is commonly used by forensic investigators in the analysis of latent fingerprints on porous surfaces such as paper. Amino acid containing fingermarks, formed by minute sweat secretions which gather on the finger’s unique ridges, are treated with the ninhydrin solution which turns the amino acid finger rid

Curcumin

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Curcumin is the principal curcuminoid that present in member of ginger family (Zingiberaceae).  The curcuminoids are natural phenols and are responsible for the yellow color of turmeric. Curcumin can be used for boron quantification in the curcumin method. It reacts with boric acid forming a red colored compound, known as rosocyanine ( en.wikipedia.org ). Curcumin has the ability to dramaticaly lower the risk of heart diseasa, cancer and alkzeimer. molecule structure of Curcumin

Ingenhousz Experiment

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Objective To prove the photosynthesis result is O 2 Base theory Plants as the autotroph organism have ability to produce organic matter from anorganic matter. This ability because plants have organel called chloroplast. In the daylight, the sunshine reach the chloroplast and plants can transform H2O and CO2 into carbohydrate and O2. Carbohydrate will be saved as food reserves and to build cell wall. The reaction of photosynthesis: 6H 2 O + 6CO 2 ----> C 6 H 12 O 6  + 6O 2 Tools and materials test tube bekker glass (1000 ml) funnel water plants  matches Procedure of experiment Fill the bekker glass with 800 ml of water. Prepare the plant, put the plant in the funnel. Enter the funnel and the plant into bekker glass with inverted. Enter the tip of the funnel into the test tube. Look at the picture! Place the bekker glass in the outside (there is sunshine). Waiting for 15 minutes. Lift the test tube and closed its hole with your hand. Light a match an

Formaldehide

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Formaldehide  (CH2O) is a colorless gas that have pungent odor. Commercial solutions of formaldehyde in water, commonly called formalin, were formerly used as disinfectants and for preservation of biological specimens ( en.wikipedia.org ). Commonly formaldehide formed from reaction catalitic oxidation from metanol. So every day it formed from burned of cigaret, fuel and our woods. Our cell body also produce it as a metabolic product. In our athmosphere it can be produce as interaction betwen sun light and O2 with metana or other hidrocarbon. Even in small amount formaldehide can cause seriously health problem. Symptoms of low-level exposure include; runny nose, sore throat, cough, dermatitis, sleeping difficulties, headache, fatigue, breathing difficulties, sinus irritation, chest pain, frequent nausea, bronchitis, and decreased lung capacity. Signs of acute exposure include; abdominal pain, anxiety, coma, convulsions, diarrhea, and respiratory problems such as bronchitis, pneumonia

Kjedahl Method

Kjedahl method is used to determine the nitrogen compound, It also indicated the amount of protein in the material. Kjedahl is standard method for estimating protein content in food. The method consists of heating a substance with sulfuric acid, which decomposes the organic substance by oxidation to liberate the reduced nitrogen as ammonium sulfate. In this step potassium sulfate is added to increase the boiling point of the medium (from 337°F to 373°F / 169°C to 189°C). Chemical decomposition of the sample is complete when the medium has become clear and colorless (initially very dark). The solution is then distilled with sodium hydroxide (added in small quantities) which converts the ammonium salt to ammonia. The amount of ammonia present (hence the amount of nitrogen present in the sample) is determined by back titration. The end of the condenser is dipped into a solution of boric acid. The ammonia reacts with the acid and the remainder of the acid is then titrated with a sod

Biuret Test

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Objective The biuret test is a chemical test used for detecting the presence of peptide bonds. Base Theory In the presence of peptides, a copper(II) ion forms a violet-colored complex in an alkaline solution.Several variants on the test have been developed. The Biuret reaction can be used to assay the concentration of proteins because peptide bonds occur with the same frequency per amino acid in the peptide. The intensity of the color, and hence the absorption at 540 nm, is directly proportional to the protein concentration, according to the Beer-Lambert law. In spite of its name, the reagent does not in fact contain biuret ((H2N-CO-)2NH). The test is so named because it also gives a positive reaction to the peptide bonds in the biuret molecule. Procedure An aqueous sample is treated with an equal volume of 1% strong base (sodium or potassium hydroxide most often) followed by a few drops of aqueous copper(II) sulfate. If the solution turns purple, protein is present. 5–160 mg/mL