04.30.09
Certified Organic Actives for Cosmetic Formulations
Silab researchers have developed Ecocert-certified actives with good anti-aging, anti-free radical, moisturizing and soothing properties.
David Boudier, Catherine Lenaers, Claire Sabbadini, Delphine Creel, Brigitte Closs
Silab, Brive Cedex, France
More info: silab@silab.fr
With more consumers interested in following a healthy and eco-conscious lifestyle, de- mand for natural and organic beauty care products has grown tremendously in the past couple of years. Indeed, it is more than a trend, consumers today expect their cosmetics to be natural. Silab has more than 20 years of experience in the field of natural active ingredients. Most recently, we have developed a range of certified organic active ingredients that respond to the main cosmetic claims: anti-aging, anti-free radicals, moisturizing and soothing.
These active ingredients have proven benefits and are certified “natural and organic” by Ecocert. They are developed from plants grown using organic farming methods and according to Ecocert requirements.
Figure 1: Diagram representative of developed organic active ingredients and the associated cosmetic claims. |
As shown in Figure 1, specifically, Silab has developed six certified organic active ingredients:
• Alfalfa extract (INCI: Water and Medicago sativa (alfalfa) extract);
• Rye extract (INCI : Water and Secale cereale (rye) seed extract);
• Oat extract (INCI: Water and Avena sativa (oat) kernel extract);
• Myrtle extract (INCI: Water and Myrtus communis leaf extract);
• White lupine extract (INCI: Hydrolyzed lupine protein); and
• Linseed extract (INCI: Hydrolyzed linseed extract).
All are certified organic by Ecocert, and all are safe and easy to use.
This article details the testing carried out in our labs that proved the efficacy of these organic active ingredients.
Organic Rye Extract
When mechanical stress (gravity) is applied to the skin, it changes the structure of the fibroblast cytoskeleton. The cells produce a large number of stress fibers composed of alpha-Smooth Muscle Actin (α-SMA) in order to increase their retractile properties.1 In parallel, activated mechano-receptors combine with α-SMA to form mature mechano-receptors. They ensure the continual equilibrium between contraction and relaxation of the skin, enabling homeostasis of the extracellular matrix to be regulated.
The association of mechano-receptors with α-SMA is essential for generating tension forces but it also plays a central role in regulating the mechanical resistance of the dermis.2
In a relaxed collagen gel, the expression of stress fibers by fibroblasts is reduced.3 In addition, fibroblasts from old skin are characterized by short and disorganized stress fibers, in contrast to the fibroblasts of young skin in which fibers are long and parallel to the longitudinal axis of the cell.4 Disorganization of the cytoskeleton causes a reduction in retractile forces and this deteriorates mechanical resistance of the skin.
To counteract effect of mechanical stress, we developed an organic rye extract that is rich in arabinoxylans.
Synthesis of α-SMA
In-vitro studies were conducted by Western blot and fluorescence immunocytology on a pool (four donors) of normal human fibroblasts (NHF) (passage 7) compared to a model of aged human fibroblasts (AHF) (passage 24).
When tested at 0.25% and 0.50% on NHF, the organic rye extract significantly increased the quantity of α-SMA by 16% and 22%, respectively, compared to the control. In cultures of untreated AHF, the quantity of α-SMA decreases significantly by 49% compared to untreated NHF.
The organic rye extract at 0.25% and 0.50% increases significantly by 16% and 19%, the synthesis of α-SMA, on AHF. This effect is visualized by immunocytology (Figure 2).
Figure 2: Effect of the organic rye extract on the synthesis of α-SMA by NHF and AHF. |
Skin Biomechanical Properties
To measure the material’s effect on skin’s biomechanical properties, the study was conducted on 20 healthy female volunteers, 37-72 years old (mean age 56 ± 11). Measurements on the face were conducted using a SEM 575 Cutometer (Courage & Khazaha).
In this study, after 56 days of twice daily applications and compared to the placebo, the organic rye extract formulated at 4% in an emulsion:
• Significantly increased parameter -X characteristic of skin tone by 19% (P = 0.0052). The study found shows that 75% of the volunteers exhibited improved skin tone.
• Improved skin tension by significantly increasing parameter –Uf by 13% (P = 0.0011). According to the study, 80% of the volunteers exhibited improved skin tension.
Organic Myrtle Extract
Organic myrtle extract is rich in hydrolyzable tannins. In the case of excessive exposure to extrinsic stressing agents; i.e., prolonged exposure to the sun, occupational exposure to chemicals, etc., free radicals formed can cause cellular damage such as:
•Oxidation of proteins causing a loss in their functionality;
• Deterioration of nucleic acids with the formation of pyrimidine dimers or strandbreaks; and
• Lipid peroxidation, leading to increased cell permeability.
The major consequences of this uncontrolled oxidative stress and the accumulation of the resulting cell damage led to the deterioration of skin structure and its accelerated aging.5,6
In order to limit aging induced by oxidative stress, the use of cosmetic active substances such as the organic myrtle extract rich in hydrolyzable tannins with anti-free radical activity is widespread.
In an assay of glutathione content, normal human fibroblasts were submitted to the complex hypoxanthine—xanthine oxidase stress with or without the product at different doses and after two hours of incubation, glutathione was assayed with the Glutathione Assay Kit II (Calbiochem, Cat. No. 354103). Total proteins were assayed with the BCA Kit (Sigma, BCA1).
The organic myrtle extract at 0.25%, 0.5% and 1% leads to a significant recovery, 19%, 55% and 66%, respectively, of the glutathione content of cells subjected to HX-XO aggression.
To measure anti-lipoperoxidant effects, a study was carried out on 19 healthy female volunteers, 28 -47 years old (mean age 39 ± 6). After a 14-day, twice daily pre-treatment of the forearms by the organic myrtle extract formulated at 3% in an emulsion vs. placebo, we induced the formation of lipoperoxides on the forearm by local application of a patch containing 0.5% methyl nicotinate (MN).7,8
Lipoperoxides were sampled before and 24 hours after the application of the patch, by using absolute ethanol and stored at -20°C. Lipoperoxides were assayed with a spectrophotometric method at the wavelength of 500nm, using a calibration range of lipoperoxides (Interchim, Cat. No. ref 705014).
In the conditions of this study, after a 14-day, twice daily pretreatment and in comparison to the placebo, the organic myrtle extract formulated at 3% in an emulsion, significantly limits the formation of lipoperoxides caused by the application of a patch of MN by 16.2% (P = 0.0468) (Figure 3).
Figure 3: Anti-lipoperoxidant effect of the organic myrtle extract formulated at 3% in comparison to the placebo. |
Organic White Lupine Extract
Organic white lupine extract is rich in glutamine-containing peptides and oligosaccharides. The stratum corneum provides mechanical protection of the body on the macro-scale and its barrier function has two components: corneocytes and epidermal lipids. This layer is constantly abraded by chemical and physical agents and renewed by a very slow process of cornification, which transforms keratinocytes into corneocytes. This naturally coordinated and regulated process consists in the synthesis of epidermal lipids and the formation of the cornified envelopes.7
During severe chemical or physical attacks on the skin, the stratum corneum is no longer replaced properly, and the skin becomes dry and rough. Under these circumstances it is necessary to support and stimulate the renewal process of this layer; that is, the role of the organic white lupine extract rich in glutamine-containing peptides and oligosaccharides.
To measure epidermal lipid synthesis, an ex-vivo study was investigated on human skin explants using thin layer chromatography (HPTLC). Human skin explants, obtained from an abdominal plasty of a 29 year-old woman, were topically treated with 1% certified organic white lupine extract for 18 hours. The neosynthesized radiolabeled lipids were extracted, separated by HPTLC and then quantified with a radioactivity analyzer (Storm – Amersham).
In comparison with the control, the 1% organic white lupine extract increased the newly synthesized epidermal lipids of different classes (Figure 4):
• polar lipids by 64%;
• ceramides by 44%;
• cholesterol and cholesterol sulfate by 100% and 45% respectively; and
• cerebrosides by 20%.
Figure 4: Effect of the organic white lupine extract on the neosynthesis of different class of epidermal lipids. |
To assess the effect of the lupine extract on skin barrier function, a study investigated the effect vs. placebo of the organic white lupine extract formulated at 4% in an emulsion on transepidermal water loss (TEWL). Twenty female volunteers (mean age 39±9) applied the products on the upper arms after washing the skin with sodium lauryl sulfate (SLS) at 10%. Measurements were made using a Tewameter TM 210 (Courage & Khazaka) before and after 14 days of twice-daily treatment.
Compared to the placebo, the 4% organic white lupine extract significantly reduced TEWL by 11% after repeated SLS aggression (P=0.0395).
Organic Linseed Extract
Organic linseed extract is rich in polysaccarides and peptidoglucans. The skin is exposed to a number of stress elements, including cold, wind, pollution, ultraviolet radiation, poorly adapted cosmetic products and detergents. Faced with these irritants, even the most resistant skin becomes fragile and sensitive and responds with inflammatory reactions that are visible, intense and unpleasant.
Extracted and purified from linseed obtained from organic farming, and known for its emolliency and anti-inflammatory properties, the acid polysaccharides (uronic acids, β-glucan) and peptidoglycans of the organic linseed extract can prevent, or least limit, irritation by acting on the synthesis of key molecules in the inflammatory cascade.
To measure the effect of the linseed extract on the release of prostaglandins E2 (PGE2), normal human keratinocytes (NHK) were treated with 2.5 µM arachidonic acid in the presence of the organic linseed extract at 0.5% or 1%. After three hours of incubation, cell-free supernatants were recovered and PGE2 were assayed with a specific ELISA assay kit (Amersham GE Healthcare, Cat. No. RPN 222).
When subjected to inflammation induced by arachidonic acid, NHK secrete significantly more PGE2. Tested at 0.5% and 1%, the organic linseed extract significantly reduces the release of PGE2 by 29% and 34%.
To measure the organic linseed extract’s effectiveness as a soothing agent, a study was conducted on 20 healthy male and female volunteers, 21-35 years old (mean age 28 ± 4) who were pre-selected for their sensitivity to lactic acid.
The effect of organic linseed extract formulated at 4% or a placebo on skin reactivity after application of a solution of lactic acid was assessed using a four-point numerical scale, before and after a 5-day and 28-day pretreatment (Figure 5).
Figure 5: Effect of the organic linseed extract formulated at 4% on the sensations of stinging caused by a solution of lactic acid. |
In the conditions of this study and in comparison to the placebo, the organic linseed extract formulated at 4% in an emulsion significantly reduces the sensations of discomfort resulting from the application of a 10% solution of lactic acid on nostril “wings”:
• after 5 days of pretreatment: -18%; P = 0.0660; and
• after 28 days of twice daily use: -25%; P = 0.0119.
The distribution of the results showed that 70% of the volunteers reported this effect.
Conclusion
The current trend in cosmetic formulation is to use more natural or organic components in the composition of final products. Silab’s expertise in natural active ingredient conceptsenabled us to develop a range of certified organic active ingredients with standards very close to those used in the development of natural actives.
Silab’s Natural and Organic range is Ecocert certified. This defines a requirement level guaranteeing the genuine practice of environmental respect throughout the production line, from the raw material (coming from certified organic farming) to the finished product. In accordance with Ecocert, these certified organic active ingredients, are made of:
• More than 99% of each ingredient is of natural origin, and
• More than 99% of the ingredient is derived from organic farming, as indicated on their labels.
They meet the main expectations of the cosmetic industry: anti-aging, anti-free radicals, moisturizing and soothing.
• The organic alfalfa extract, rich in galactomannans, protects the dermal matrix with a similar activity to retinol and presents an anti-wrinkle effect (data not shown).
• The organic rye extract, rich in arabinoxylans, stimulates the synthesis of alpha-SMA on senescent fibroblast and significantly improves skin biomechanical properties.
• The organic oat extract, a purified fraction of natural polyoses, presents an immediate tensor effect, proven instrumentally and sensorially (data not shown).
• The organic myrtle extract, rich in hydrolyzable tannins, stimulates the skin’s natural antioxidant defenses. Then, it acts as a metal chelator and protects skin cells from attack of free-radicals chemically-induced (data not shown). Tested in-vivo, it limits the formation of lipoperoxides and thus prevents skin aging.
• The white lupine extract strengthens the epidermal reinforcement of the skin by stimulating the synthesis of epidermal lipids and proteins (data not shown). Tested in-vivo, it limits the transepidermal water loss.
• The organic linseed extract limits the phenomena of irritation by decreasing the release of interleukins-1α (data not shown) and PGE2, key molecules in the inflammatory cascade. Tested on volunteers, it reduces the uncomfortable sensations caused by the application of a lactic acid solution.
These six certified organic active ingredients, all with proof of efficacy demonstrated in-vitro and in-vivo, enables the cosmetics industry to meet growing consumer demand for effective authentic, natural and/or organic and effective cosmetic products.
References
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3. Lambert CA., Colige AC., Lapière CM., Nusgens BV. Coordinated regulation of procollagens I and III and their post-translational enzymes by dissipation of mechanical tension in human dermal fibroblasts. Eur. J. Cell. Biol., 80, 7, 479-485 (2001).
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