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ISOLATION OF PECTIN

NOOR SAAD MAHMOOD Isolation Of Pectin Pectin is a structural heteropolysaccharide contained in the primary cell walls of terrestrial . It is produced commercially as a white to light brown powder, mainly extracted from fruits. , , guavas, , plums, gooseberries, and oranges and other citrus fruits contain large amounts of pectin, while soft fruits like cherries, grapes, and strawberries contain small amounts of pectin Typical levels of pectin in plants are (fresh weight): • apples, 1–1.5% • , 1% • cherries, 0.4% • oranges, 0.5–3.5%

The main raw materials for pectin production are dried citrus peel or pomace, both by-products of juice production Chemistry of pectin : Pectins, also known as pectic , are rich in galacturonic acid .Isolated pectin has a molecular weight of typically 60–130,000 g/mol, varying with origin and extraction conditions. In nature, around 80 percent of carboxyl groups of galacturonic acid are esterified with . This proportion is decreased to a varying degree during pectin extraction. The ratio of esterified to non-esterified galacturonic acid determines the behavior of pectin in food applications. This is why pectins are classified as

• high- pectin. • low-ester pectins , with more or less than half of all the galacturonic acid esterified. Chemistry of pectin :

• Some plants such as beet, potatoes and pears contain pectins with acetylated galacturonic acid in addition to methyl . Acetylation prevents gel-formation but increases the stabilising and emulsifying effects of pectin.

• Amidated pectin is a modified form of pectin. Here, some of the galacturonic acid is converted with to . The main use for pectin is as

• The main use for pectin is as • gelling agent • • stabilizer in food. The classical application is giving the jelly-like consistency to jams or In some countries, pectin is also available as a solution or an extract, or as a blended powder, for home jam making.

• For conventional jams and marmalades that contain above 60% sugar and soluble fruit solids, high-ester pectins are used. • With low-ester pectins and amidated pectins less sugar is needed, so that diet products can be made. In Medicine 1. pectin increases viscosity and volume of stool so that it is used against and .It was one of the main ingredients used in Kaopectate a medication to treat diarrhea, along with kaolin .. However, in April 2003, the FDA found that scientific evidence does not support the use of pectin for diarrhea. Since April 2004, pectin has not been permitted as an anti-diarrhea agent in over-the-counter (OTC) products.

2. Pectin is also used in throat lozenges as a demulcent. 3. Gastroesophageal reflux A pectin-based, raft-forming, antireflux agent available .This product reduces the amount of food and acid concentration reaching the esophagus, thus reducing heartburn.

4. Taking pectin by mouth seems to lower cholesterol Taking it along with guar gum and small amounts of insoluble fiber lowers total and “bad” low-density lipoprotein (LDL) cholesterol. However, the combination doesn't seem to affect “good” high-density lipoprotein (HDL) cholesterol or triglycerides. Side effects • In most people, including adults, children, and women who are pregnant or breast- feeding, pectin is LIKELY SAFE. • When taken by mouth in combination with guar gum and insoluble fiber (the combination used to lower cholesterol and other blood fats), pectin can cause diarrhea, gas, and loose stools. • People who are exposed to pectin dust at work, such as in manufacturing, may develop asthma interactions • Antibiotics (Tetracycline antibiotics) interacts with PECTIN • Digoxin (Lanoxin) interacts with PECTIN • Lovastatin (Mevacor) interacts with PECTIN Procedure: • Remove the pericarp from the grapefruit (citrus paradise). • Accurately weigh about 25gm and cut the tissue, using a scissors or knife, into cubes about 1cm square, place the tissue in a beaker and add 100ml of water and 1.5 ml of 3N H2SO4 acid. • Heat the mixture with occasional stirring to 90°C. • continue the digestion at 85_90°C for 30 minutes, strain the mixture through cheese cloth expressing the tissue to collect the solution, repeat the digestion for 15 minutes, strain and combine the extract. • filtrate using Buchner funnel collect 100 ml of pectin solution add isopropyl or ethyl alcohol to concentration of 55% by volume. • collect the ppt with 25ml of alcohol. dry the product compute the percentage of pectin and submit the product to the laboratory instructor.