Determination of amount of retinylpalmitate and ascorbic acid of extract gel of sweet corn fibre by UVand HPTLC method

The Corn Fiber

Corn is an agricultural product with large quantities of starch. Manufacturers extract this from the plant fibers, break it down into sugars, ferment them and separate them into polymers.

The advantages in the use of corn fiber

The fabric made from corn fiber hardly requires maintenance, is fairly cheap and comfortable to wear. There are also the advantages of the fiber being stain-resistant and does not fade easily. So applications like readymade apparel, diapers, bedding, carpets and upholstery come out well

Retinol, also known as vitamin A1-alcohol, is a vitamin in the vitamin A family ^[1] found in food and used as a dietary supplement. ^[2] As a supplement it is ingested to treat and prevent vitamin A deficiency, especially that which results in xerophthalmia. ^[1] In regions where deficiency is common, a single large dose is recommended to those at high risk a couple of times a year. ^[3] It is also used to reduce the risk of complications in those who have measles. ^[3] It is used by mouth or injection into a muscle. ^[1]

Retinol at normal doses is well tolerated. ^[1] High doses may result in an enlarged liver, dry skin, or hypervitaminosis A. ^{[1] [4]} High doses during pregnancy may result in harm to the baby. ^[1] It is converted in the body to retinal and retinoic acid through which it acts. ^[2] Dietary sources include fish, dairy products, and meat. ^[2]

Retinol was discovered in 1909, isolated in 1931, and first made in 1947. ^{[5] [6]} It is on the World Health Organization's List of Essential Medicines. ^[7] 

Retinol is used to treat vitamin A deficiency.

Vitamin C (also known as ascorbic acid and ascorbate) is a vitamin found in various foods and sold as a dietary supplement. ^[8] It is used to prevent and treat scurvy. ^[8] Vitamin C is an essential nutrient involved in the repair of tissue and the enzymatic production of certain neurotransmitters. ^[8], ^[9] It is required for the functioning of several enzymes and is important for immune system function. ^[9], ^[10] It also functions as an antioxidant. ^[11]

There is some evidence that regular use of supplements may reduce the duration of the common cold, but it does not appear to prevent infection. ^[11], ^[12] Vitamin C is generally well tolerated. ^[8] Large doses may cause gastrointestinal discomfort, headache, trouble sleeping, and flushing of the skin. ^[8], ^[11] Normal doses are safe during pregnancy. ^[7] The United States Institute of Medicine recommends against taking large doses. ^[9]

Reagents

Absolute ethanol, Phenolphthalein solution-1%, Hexane (C6H14), Sodium hydroxide solution-0.1 N.

Procedure

Weigh approximately 1 g of corn fibre extract and add about 100 mL hot water at 85°C. Use a glass rod to completely dissolve the sample.

Cover the beakers with a watch glass or aluminum foil 6

Cool them to room temperature in a dark place. An ice bath can be used for this purpose.

Measure 5 mL of the solution prepared in steps (4 or 5) into a 50 mL test tube.

Prepare triplicates for each sample

Add 5 mL of 0.1 N-sodium hydroxide to each tube and mix in a Vortex for 30 seconds.

Add 2-3 drops phenolphtalein-1% m/v to the same tubes. Then, add 5 mL absolute ethanol to each tube. Mix in the vortex mixer for 5 seconds.

Measure 5 mL of hexane and add it to each tube from step (8). Immediately close with a cap each tube and mix vigorously with the vortex mixer for 30 seconds to ensure complete extraction of the retinyl palmitate. Open the tubes briefly to release the vapor pressure. Allow separation of phases. The aqueous phase has a fuchsia color, and the top organic solvent phase is colorless.

Recording absorbance of the extracted vitamin A

As soon as possible, transfer the organic phase, using a Pasteur pipette to a 1 cm light path spectrophotometer cuvette and read the absorbance at 326 nm. Adjust the zero of spectrophotometer with hexane before each reading.

Calculations The retinyl palmitate concentration of the sugar sample is calculated using the following equation:

Retinyl palmitate(mg/kg)=Abs corrected/Qx Vorg/VsamxVi/wxCF/RxD

Where: Abs corrected = Abs sample – Abs blank And Abs blank is the average for the three readings, which should be less than 0.050

The equation parameters are: To express the results as unesterified retinol, the ratio of the molecular weights of retinol/retinyl palmitate (286.46/524.84 = 0.546), must be taken into consideration.

Spectrophotometric determination of abscorbic acid in the extract

Preparation of Standard solution: Different concentrations of ascorbic acid were preprared by diluting the ascorbic acid with water to make 1000 ug/ml. And it is further diluted to 1-5 ug/ml concentrations and absorbance value were noted at 260 nm. And the calibration curve was drawn.

And the absorbance value of corn powder gel was also determined and found to be 0.338 nm and from the calibration graph the amount of ascorbic acid was found to be 2.89 ug/ml.

HPTLC determination of corn fibre extract gel

The Chromatographic estimation was performed by spotting standards and extracted samples on pre-coated silica gel aluminium plate. Plates were developed using a mobile phase consisting of Methanol and water (8:2v/v).Linearity of the method was studied by spotting various concentrations and found to be linear in the range of 5-10 ug/ml