Sunflower wax as a New Natural Cosmetic Raw Material: Purification and Application in Lipsticks

 

A Maru*, U Pattamatta and VB Patravale

Loknete Dr J D Pawar College of Pharmacy, A/P Manur, Tal. Kalwan, Dist. Nasik  Maharashtra, India

 

ABSTRACT

Sunflower Wax is a component of the hull of sunflower (Helianthus annus) oil seeds. The wax is essentially composed of extensively saturated esters of long chain fatty acids (C20-C22) and fatty alcohols (C22-C29). Due to its low economical value, it is often considered as industrial waste. Thus, the focus of the work was to purify the wax and explore its use in cosmetic product, lipstick. The replacement of beeswax with sunflower wax did not alter the properties of the lipstick, thereby providing an economical alternative to beeswax.


1. INTRODUCTION:

Lipstick is one of the decorative cosmetic products that command a unique market. Advanced technology has been used to manufacture modern lipsticks with vast functionality. In the last quarter of twentieth century, cosmetic industries exist with technology of their own. Every year, users were introduced with various new cosmetics products of the latest trend. The quality of lipstick is directly linked to the basic material used in the formulation. Varying the ratio of the ingredient used determines the final product characteristic.1 In this work, a new natural wax, Sunflower Wax has been explored to formulate lipstick with desired attributes.

The Sunflower Wax is obtained from the hull of sunflower (Helianthus annus) oilseed which also gives the highest oil yield. Because of its high B vitamin and protein content, and also its balance amino acid composition, the sunflower oil cake can be favorably compared to the best oil cakes (soya, peanut). 2 As with the other oilseeds, the production of the oil liberates an enormous quantity of the low density hull as byproduct. Due to limited use, hull often accounts for major waste, making its utilization an important industrial problem. 2

 In the early seventies, tremendous work has been done by Cancalon to provide detailed chemical composition of the hull wax. (table1-2)  These waxes are mainly located in the hull of sunflower seeds with concentrations up to 3% depending on the hybrid and origin of the seed. 3-6 Thus, the work involved purification of the sunflower wax, characterization of the pure wax and evaluation its application in lipsticks.

 

2. EXPERIMENTAL:

2.1. Materials

Sunflower wax was generous gift sample from Maru Industries, Malegaon

 

2.2 Purification of sunflower wax

Sunflower wax was purified by treating the wax with different solvents such as acetone, hexane and petroleum ether. The wax was shredded using a shredder and a mixture of 10 gm shredded wax alongwith 20 ml of the solvent was taken in a conical flask with stopper. The mixture was shaken for one hour and the resultant white crystalline wax was filtered out. Oil was recovered by distilling out acetone.

 

2.3. Characterization of the purified sunflower wax

2.3.1. Melting point

Melting point of the sunflower wax was determined by the drop point method. The wax was applied to the thermometer bulb and inserted

 



through a stopper into a test tube. This assembly was kept in a beaker with water. Then, it was heated at a rate not exceeding 0.5 οC/ min.

 

2.3.2. Specific gravity

A graduated measuring cylinder was filled with a mixture of equal volumes of water and alcohol. The specific gravity of this mixture was determined using specific gravity bottle. To the measuring cylinder, 20 g if the wax was added and the increase in the volume of the liquid was noted.

 

2.3.3 Hardness

The hardness was found out by using the penetrometer. A load of 100g was taken and the depth to which the needle penetrated through the sample was noted.

 

2.3.4. Saponification value

2.269 gm of wax was taken in conical flask containing 30 ml absolute alcohol. 25 ml of approximately 1N alcoholic KOH was gently added into the flask with constant stirring. The contents of the flask were refluxed for at least one hour with occasional shaking.When the mixture started boiling, the the excess of KOH was titrated with 0.1 N HCl using a mixture of phenolphthalein and 1 ml of methylene blue as an indicator. Mixtures of indicators so that the end point were sharply distinguished  from a brownish purple to clear pale  or dark green colour. The saponification value was found out by the following formula

 

Saponification value = (Vb Vw x 56.104 x NHCl) / W

 

Where, W= weight of sample taken, Vb, Vw are respectively number of millimeters of normal HCl using in the blank and actual analysis.

 

2.3.5. Acid Value

4 gm of wax was warmed with 50 ml of carefully neutralized alcohol in a 250 ml flask. A few drops of phenolphthalein was added to the mixture and titrated with vigorous shaking against 0.1 N alcoholic KOH until a semi pink color appeared.

               Acid Value = (Vw x 56.104 x NKOH)/ W

 

2.3.6. Ester Value

The ester value was determined by deducting the acid value from the saponification value.

 

2.3.7. Iodine Number

0.5 g of wax was dissolved in 10 ml of CCl4 in a dry I2 flask. 20 ml of previously moistened with dilute KI, ICl solution was added and the stoppered mixture was allowed to stand in the dark at 15οC to 25 οC for 30 minutes. 15 ml of dilute KI solution was carefully   introduced in the mixture and then diluted with 100ml water. The solution was titrated with 0.1 M sodium thisulphate using starch mucilage as an indicator. Iodine value was calculated using the following equation;

               Iodine value =1.269 Vx N/w

Where, V= difference in ml between the titrations; w= Weight in gms of the substance taken.

 

2.3.8. Unsaponifiable matter

For the unsaponifiable matter, the alcohol was distilled off from the saponified sample and the residue was taken up in 200cc of water and placed in a 500 cc separator; ether (200cc) was added, and the whole was shaken gently. The aqueous layer was twice extracted with ether.

 

2.4. Formulation of Lipsticks

The colour lake, bromo acid and titanium dioxide were thoroughly mixed. A mixture of castor oil, isopropyl myristate, lanolin and preservative were added to the staining dye mixture and heated on a water bath with continuous stirring. Waxes were melted in another beaker and this was mixed with colour dispersion and then stirred slowly. This mass was removed from the water bath, perfume was added and then it was poured into lubricating molds. The lipstick was allowed to set in the molds.

 

2.5. Evaluation of Lipsticks:

2.5.1. Softening point

Lipstick was placed with protruded salve in the flat bottom tube. Thermometer was fixed through a cork in such a way that the bulb of the thermometer just touched the lipstick salve. The arrangement was inserted into a 1 litre beaker filled with water to a level one centimeter above the upper tip of the lipstick salve. Slowly water bath was heated while stirring so that temperature rises at a rate not exceeding 2 οC/ min. When the temperature reached about 45 οC, the temperature was raised at the rate of 1 οC/ min. The temperature,   the salve starts bending and losing its shape was recorded as the softening point.

 

2.5.2. Bending load test

Lipstick container was firmly fixed with protruded salve into a screw type of chuck so that the assembly was perfectly horizontal. Burette was adjusted just above the lipstick salve. Marking was made at a distance of 1.5 cm from the base of the salve where the lipstick salve sits in salve holder. The aluminum container was weighed along with hook and suspended. On this 1.5 cm mark, water was released form the burette into the aluminum container till the slave breaks. Burette reading was added with the mass of the suspended container gives the breaking load of the lipstick.

 

2.5.3. Pay off test

The apparatus consists of constant speed electric motor of power 180 watts attached to gear arrangement, which pulls the strip of paper from a roller onto another roller fixed on platform through a support. A slot arrangement having a cylindrical tube of 4 cm length and 1.7 cm diameter is also fixed on the platform. The top portion (approx 1 cm) of the lipstick salve was chopped off using a sharp blade. Remaining portion of the salve was rubbed on a piece of paper and there by the end portion was made perfectly flat. Constant speed motor was run and the time required for pulling out 100 cm of the paper length was determined. The lipstick was inserted in the slot arrangement so that the flattened slave portion rests on the surface of the paper strip. A load of 50g was placed on the top of the lipstick. Constant speed motor was started and with the help of stopwatch 100 cm length of paper was allowed to run. Lipstick after rub off was weighed. The length and breadth of the lien drawn on the paper strip was measured.

               Pay-Off (g/cm2) = (M1-M2)/ Lx B

Where, M1 = Mass of the lipstick before the test

M2 = Mass of the lipstick after the test

L = Length in cm of the line drawn on paper strip

B= Breadth in cm of the line drawn on paper strip

 

Table1: Wax Fatty acid Composition2

Fatty Acids

Percent a

Myristic

1.94

Pentadecanoic

0.4

Palmitic

6.8

Heptadecanoic

0.2

Iso-stearic

0.35

Stearic

5.6

Oleic

4.72

Nonadecylic

3.07

Linoleic

0.78

lso-arachidic

1.3

Araehidic

46.5

lso-medullic

0.9

Medullic

0.7

Behenic

16.3

Tricosanoic

0.53

Lignoceric

4.5

Pentacosanoic

0.23

Montanic

2.2

a Unknown peaks account for the difference between the total and 100%.

 

Table2: Wax Fatty Alcohol Composition2

Fatty Alcohol

Percent a

Dodecanol

0.16

Tridecanoic

0.24

Tetradecanol

traces

Pentadecanol

traces

Hexadecanol

0.2

Heptadecanol

0.17

Octadecanol

3.0

Oleilol

O.15

Nonadecan el

0.17

Eicosanol

2

Heneicosanol

0.15

Docosanol

12

Tricosanol

0.4

Tetraeosanol

34.6

Pentacosanol

3.45

Hexacosanol

14.35

Octacosanoi

6.65

Nonaeosanol

5.75

Triacontanol

2.17

a Unknown peaks account for the difference between the total and 100%.

 

Table3: Characterization values of refined Sunflower wax

Parameters

Results

Colour

White

Melting Point

78 οC

Specific gravity

0.8445

Softening point

75 οC -76 οC

Hardness

18

Saponification Value

75.3666

Acid Value

5.213

Ester Value

.70.152

Iodine Value

0.748

Unsaponifiable matter

45

 

 

2.5.4. Test for Heavy Metals

The colour produced with hydrogen sulphide solution was matched against that obtained with standard lead solution. 1.6g of lead nitrate was dissolved in water and the solution was made up to 100 ml. 10 ml of solution was pipetted out and diluted to 1000 ml with water (0.01mg of lead/ml).

 

1g of the material was dissolved in 3 ml of dil. HCl with slight warming. This was diluted to 50 ml with water. The solution was filtered, 25 ml of  filterate was transferred into a Nessler cylinder, 2ml of dilute acetic acid, 1 ml of standard lead solution was added and volume made upto 25 ml. 10 ml of hydrogen sulphide solution was added to each Nessler cylinder volume was made upto 50 ml  with water. It was then allowed to stand for 10 minutes and the colour produced in both the Nessler cylinders was compared.

 

 

Table4: Composition of Lipstick formulations

Ingredients

Standard formulation (10g)

Developed formulation

(10g)

Carnauba wax

0.3 g

0.3 g

Candellia wax

0.1 g

0.1 g

Ozokerite wax

0.3 g

0.3 g

Beeswax

0.7 g

---

Sunflower wax

---

0.7 g

Lanolin

1 g

1 g

Castor Oil

6.5 g

6.5 g

Isopropyl myristate

0.5 g

0.5 g

Colour

0.5 g

0.5 g

Perfume

q.s.

q.s.

Preservative

0.1 g

0.1 g

 

Table5: Characterization values of standard and developed lipsticks

Test

Standard formulation

Developed formulation

Melting Point

60 οC

61 οC

Softening Poitn

58 οC

60 οC

Pay- Off test

3.8 x 10-4 g/cm2

3.5 x 10-4 g/cm2

Penetrometer Test

0.6 cm

0.55 cm

Breaking Load test

395

410

Particl Size

4.1 microns

4.9 microns

Test for heavy metals

Colour produced in the developed formulation was comparable to standard.

Test for arsenic

 

 

2.5.5. Test for Arsenic

2g of the sample was weighed in a flask of 500 ml capacity. 15 ml of concentrated sulphuric acid was added followed by 4 ml of concentrated nitric acid and cautiously heated. Dropwise addition of Nitric acid was done to hasten the rate of oxidation of the sample. The completion of oxidation was indicated by clear and faint yellow solution; at this stage 20 ml of water was added and boiled to fuming. The stain of the sample and standard (0.004g of arsenic dioxide) was compared.

 

2.5.6. Penetrometer test

Lipstick was melted to 70 οC and molded in stainless steel tube.  It was alloed to set for 24 hrs. After setting the lipstick rod was removed form the cast and cooled to 25 οC. The molded lipstick rod was placed horizontally on the penetrometer platform. The penetrometer need le was adjusted so that it just sits on the surface of the molded lipstick rod. The needle attachment was released and the penetrating reading was recorded. Penetration on several points on the surface of the lipstick was determined and the average of all such determinations was reported in micrometer.

 

2.5.7. Particle size of undispersed pigments

A small portion of the lipstick paste was applied on glass slide. The slide was observed under the microscope using a specially calibrated eye piece. The particle size of the largest pigment particle was determined.

3. RESULTS AND DISCUSSIONS

3.1. Purification of sunflower wax

Sunflower wax was purified by removing the oil using different solvents like acetone, hexane and petroleum ether. Since the sunflower oil seed contain highest amount of linoleate which tend to produce large quantities of volatiles, especially pentane and hexanol. Thus, at lower temperature, the removal of oil from the wax was found to be difficult.

 

When petroleum ether was used as a solvent, the wax obtained was not pure white and crystalline, this could be attributed to incomplete removal of the oil. Hence, it had to be retreated with the solvent to facilitated complete removal of the oil. Purification of was using hexane was found to be unfeasible due to partial solubility of wax in the solvent and poor removal of solvent at lower temperatures. While acetone proved to be the better solvent for removal of oil, using acetone it was possible to obtain white and crystalline wax.

 

3.2. Characterization of wax:

Chemical constants such as acid, ester , hydroxyl and iodine numbers are determined to identify, differentiate  or classify the waxes. The saponifcation number is a direct evaluation of the total amount of esters and free aids, if any, in a wax which is free from polyesters and resins. It approaches the constant number for a particular kind of wax. The acid value expresses the free fatty acid and is more of a variable then the saponifcation number. The unsaponifiable matter, is an important determination in the identification of a wax or in the study of its composition. It includes not only the unsaponifiable portion of wax such as the combined alcohols, split off from the ethers or esters as a result of saponification, but also hydrocarbons and free alcohols and ketones, if any.

The chemical constants assist greatly in determining the chemical compositions of the wax once the individual constituents are recognized by the molecular weight, melting point and other determinations. The chemical constants for refined sunflower wax have been reported in Table 3.

 

3.3. Formulation and evaluation of lipsticks

 Melting point and hardness of the wax mainly decide their application in many formulations. The requirements of a good lipsticks are that it must be non injurious, easily spreadable without being excessively greasy; its colour must be reasonably permanent; it must not sweat, crumble or crack. In addition to these qualities, its color must be absolutely uniform, unchanged and free from mottling. It will be seen from the foregoing statements that the consistency of the stick is to determined by the melting point of the waxes.

When sunflower wax was substituted for carnuba wax, the lipstick formed was very soft and was not rigid. So the entire evaluations tests were not carried out for this formulation. Sunflower wax was substituted for both ozokerite wax and beeswax. In this case, the lipstick had shown better results, but the lipstick was not hard in comparison with the standard. While formulation where only beeswax was substituted by sunflower wax, the lipstick was quite hard and comparable to standard as shown in table 5.

 

 

4. CONCLUSIONS

The demand for waxes is increasing day by day in various fields of the industry. Since India has ample cultivation of sunflower crop, the exploitation of the industrial waste, sunflower hull for the production of sunflower wax makes it a profitable prospect. Moreover, as shown by the evaluation of lipsticks containing sunflower wax, it could be concluded that sunflower wax could indeed be touted as new raw material for cosmetics applications.

 

5. REFERENCES:

1.       Awang Bono, et.al., Effect of various formulation on viscosity and melting point of natural ingredient based lipstick, Studies in Surface Science and Catalysis, Vol 159: 693-696 (2006)

2.       Paul Cancalon, Chemical Composition of Sunflower Seed Hulls, J. Am. Oil Chem. Soc., Vol. 48 (10): 629—632 (1971).

3.       Morrison, W.H., III, Variation in the Wax Content of Sunflower Seeds with Location and Hybrids, J. Am. Oil Chem. Soc.60:1013–1015 (1983).

4.       Ramos Ayerbe, et.al., A Study on the Recovery of Byproducts from the Dewaxing of Sunflower Oils of National Production, Grasas Aceites 36:1–4 (1985).

5.       Mariani, C., et.al, Minor Components of Vegetable Oils: Non-glyceridic Esters, Riv. Ital. Sostanze Grasse 66:397–401 (1989).

6.       Amalia A. Carelli, et.al,Wax Composition of Sunflower Seed Oils, J. Am. Oil Chem. Soc., Vol. 79 (8): 763-768 (2002).

 

 

Received on 10.06.2009

Accepted on 18.06.2009     

© A&V Publication all right reserved

Research Journal . of Pharmaceutical Dosage Forms  and Technology. 1(1): July.-Aug. 2009, 45-48