Shelf - life of natural cosmeceutical product: Accelerated storage and stability test.g y

Nur Zatul Iradah Bt. Roslan

UTM INTERNATIONAL CAMPUSUTM INTERNATIONAL CAMPUS

8 OCTOBER 2010

IntroductionNatural based formulation• Natural cosmetics have become a major trend inNatural cosmetics have become a major trend in

recent years• The awareness of natural resources based product is• The awareness of natural resources based product is

increasing.N t l ti t b tif d f th• Natural cosmetics serve to beautify and care for thehuman body by means of ingredients from nature.

• Natural cosmetics should stimulate and support ournatural skin functions, rather than supplantingphysiological processes.

• Natural preservatives:- Extracts (Grapefruit seed, Rosemary)- Essential oils ( Tea Tree, Neem seed, etc.)- Vitamins (Vitamin E, vitamin C)

• Loss of preservatives:p– Loss of viscosity (product becomes thinner)– Emulsion break (separation of water and oil)Emulsion break (separation of water and oil)– Cloudiness of previously clear products– Loss or change of colourLoss or change of colour– Drop on pH (product becomes more acid)

• Potassium sorbate as preservative in cosmetic:– Usually used as food preservativey p– Safe preservative in cosmetic and personal care product

especially at pH 6.5.– Good skin compatibility and easy to use, especially in salt

form.– Common microorganisms inhibited by potassium sorbate:

• Aspergillus sp.• Fusarium sp.• Penicilium sp.• Yeast• Yeast

• Microbial contamination of cosmetic products is a matter of great importance to the industrymatter of great importance to the industry

• The contamination of cosmetic product can result in their being converted into products hazardous for consumers.

• Microbiologist working in the field of cosmetics are frequently required to design preservative systems q y q g p ythat provide good protection.

l dAccelerated Testing• Predict normal shelf –life of the product.

• methods to foresee if these products can fail moremethods to foresee if these products can fail morequickly than they would under normal useconditionsconditions.

h d b f il f d i b• the need to observe failures of products is to betterunderstand their failure modes and their lifeh i icharacteristics.

• Qualitative analysis:– Accelerated storage test– Stability test– Microbiology test

• Quantitative analysis:– Arrhenius relationshipp– Design of Experiment

ObjectiveObjective

To analyse the stability of natural based creamTo analyse the stability of natural based creamformulation using accelerated storage test andmicrobial analysismicrobial analysis.

MethodologyMethodology

Preparation of base cream formulationusing Mixture Designg g

Stability test:Stability test:1) Freeze – thawing : 4°C – 24 hours, 25°C – 24hours , 3 cycles.2) Centrifugation test : 3000 rpm 30 minutes2) Centrifugation test : 3000 rpm, 30 minutes.

Microbiology analysis:Microbiology analysis: total plate count, total yeast and mould, Staph. aureus, Pseudomonas, Salmonella, Enterobacter and E. coli.

Development of a base natural creamDevelopment of a base natural cream

• Mixture design was applied to develop a base natural cream formulation (data not shown).

• Eleven independent variables were chosen to evaluate the combined effects of three responsescombined effects of three responses.

• The response values were viscosity stability and pH• The response values were viscosity, stability and pH.

Ingredients in formulationIngredients in formulation

Ingredients Action

Oil phase

Virgin coconut oil (VCO)

Palm oil

Humectants (moisturize)

Emollient (Lubricity and soothing)Palm oil

Beeswax

Glycerin

Emollient (Lubricity and soothing)

Emollient

Emulsifier

Stearic acid

Tween 80

Soy lecithin

Emulsifier

Emulsifier

Emulsifier

Water phase

Distilled water

Xanthan gum

Dilute and dispersed ingredients

SoftenerXanthan gum

Acacia gum

Potassium sorbate

Softener

Preservative/ anti-microbe agent

Preservative/ anti-microbe

Essential oils Anti-microbe agent/fragrance

Response parameter after optimizationResponse parameter after optimization

R Vi it ( P ) St bilit (%) HResponse Viscosity (cPa.s) Stability (%) pH

Predicted Observed Predicted Observed Predicted Observed

Cream 1 21 564.6 19 359 100 100 6.5 6.499

Cream 2 21 771.6 17 227 100 100 6.5 6.5

Cream 3 21 564.1 23 918 100 100 6.5 6.5

Cream 4 19 489.6 16 209 99.998 100 6.4449 6.498

Targeted parameters: viscosity 16 000 cPa.s – 24 000 cPa.s, 100% stability at pH 6.5

Final formulations (100g)Final formulations (100g)

Cream VCO Palm Oil Beeswax Glycerin Stearic Tween Soy Distilled Xanthan Acacia Potassium

acid 80 lecithin water gum gum sorbate

1 4.61 4 2.93 0.01 0.23 1.87 1.67 77.31 3.42 2.16 1.6

2 4.90 4.04 2.65 2.05 0.01 1.94 2.66 74.03 3.72 2.21 1.6

3 4.58 4.75 3.00 2.03 1.68 1.48 3.86 72.21 3.71 0.91 1.6

4 3.98 3.65 2.75 2.12 0.45 0.99 2.91 76.57 3.61 1.16 1.6

Liposome = 1%(coated with antioxidant) nanocarrierLiposome = 1%(coated with antioxidant) , nanocarrier

Antioxidant = Sodium ascorbate

Essential oils: 0.2% ≈ 200µl (Lavender, grapefruit,Ylang ylang, tea tree)

Stability test = Freeze - thawed (3 cycles )

Accelerated testing of cream formulationAccelerated testing of cream formulation

100

5060708090

tabi

lity

01020304050

% o

f s

0

1 month 2 months 4 months 6 months 12 months

Storage time

Freeze - thawed Centifugationg

• Stored at room temperatureCentrifuge at 3000 rpm 30 minutes• Centrifuge at 3000 rpm, 30 minutes

• Constant pH, 6.5

Microbiological AnalysisMicrobiological Analysis

• Analysis was done using standard method from British Pharmacopeia Year 2008.

• 10g of four final base cream formulation was analysed on total plate count, total yeast and mould, Staph. Aureus, Pseudomonas, Salmonella, Enterobacter and E. coli.

• Analysis was done for 9 months (so far) and excellent result b dwas observed.

Microbiology Analysis Results

Unit = Cfu/ gParameter Duration

g

Cream 1 Cream 2 Cream 3 Cream 4

Coated Uncoated Coated Uncoated Coated Uncoated Coated Uncoated

Total Plate Count 2 months 1.0× 10³ 2 .5 × 10³ 0 2.5 × 10³ 2.5 × 10³ 8 × 10³ 9 × 10¹ 2.5× 10³

4 months 4 × 10¹ 1 × 10³ 1.2 × 10² 5.0 × 10¹ 2.0 × 10¹ 8 × 10¹ 3.5 × 10¹ 3.0 × 10¹

9 months ND ND ND ND ND ND ND NDTotal Yeast and

Mould 2 months 2.2 × 10² 2 .5 × 10³ ND 1.0 × 10¹ ND 2 × 10¹ ND 6 × 10¹

4 months 6.5 × 10³ 3.5 × 10¹ 8.0 × 10¹ 6.0 × 10¹ ND 1.5 × 10¹ ND ND

9 months ND ND ND ND ND ND ND ND

Concluding remarksConcluding remarks

• Mixture design can be a tool to formulate stablecosmetic .

• Accelerated testing and normal storage condition hasshown that the formulation obtained from MixtureDesign was stable for at least 12 months.

• Our natural preservative system has been shown toOu a u a p ese a e sys e as bee s o oprotect from microbial contamination for at least 9nine months so far