Zgryźliwość kojarzy mi się z radością, która źle skończyła.
Clinics in Dermatology (2008)
, 321
–
325
26
Role of protein in cosmetics
Gianfranco Secchi
⁎
KELISEMA Srl, Via Urago, 13/B, 22038 Tavernerio (CO), Italy
Abstract Many authors recognize the beneficial effects of using protein-rich substances in formulations
of various topical applications. Proteins quickly were considered useful ingredients for creating a
suitable environment for healthy skin and hair because of their ability to bind water with the horny layer
of skin and its annexes. Most protein derivatives that are used for cosmetic purposes are obtained from
simple proteins, whereas conjugated proteins are used far less frequently. In this article, the role and
efficacy of proteins used in cosmetics are reported and discussed.
© 2008 Elsevier Inc. All rights reserved.
Preliminary
(hydration), Cutometer
(elasticity), Tewameter
(TEWL),
and Visioscan VC98 (SELS).
of
primary importance") play dominant roles in almost all
biological processes in living beings. Principal functions are:
enzyme catalysis, transfer and accumulation of small
molecules and ions, coordinated movement, mechanical
support, immunity protection, production and transmission
of nervous impulses, and control of growth and differentia-
tion.
1
Thus, the importance of protein use in each kind of
cosmetic product is easy to understand.
The target of the finished product could be whether the
skin, hair, or both lose their main component (proteins) in
everyday situations. In addition, it is well known that some
of the raw materials used in cosmetic formulations interact
with the skin barrier and are responsible for the modification
(mostly weakening) of the horny layer, which compromises
the skin's hydration, elasticity, firmness and softness.
Today all of this skin damage is easy to analyze and
control with different, well known, and internationally
approved skin measurement devices,
Proteins (from the Greek word proteins, which means
“
Surfactant skin irritation
The mechanisms of the adverse effects produced by
surfactants upon contact with skin and hair are not elucidated
fully, but there is general agreement that the adsorption and
interaction of their molecules to the keratin of the stratum
corneum and hair cuticle is the initial step when determining
tissue damage. Only monomeric surfactant can penetrate
when the hydrated micelles are too large to enter the tight
network of keratin fibres; thus, the concentration of tenside
monomers (and hence the critical micelle concentration
[CMC]) should be related to the skin and hair damage. Once
surfactant monomers or small aggregates initially attach to
the keratin surface, additional events and transformations
may take place. This partial denaturizing effect is based on a
combination of the following mechanisms: the hydrocarbon
tail of the surfactants penetrate the polar regions of the
keratin, replacing the conformation-stabilizing hydrophobic
interactions by ligand-segment interactions; the ionic head of
the surfactant produces attraction-repulsion forces on the
charged groups of the keratin, disordering its architecture;
like Corneometer
⁎
Tel.: +39 031 427746; fax: +39 031 427745.
E-mail address:
.
URL:
.
0738-081X/$
–
see front matter © 2008 Elsevier Inc. All rights reserved.
doi:
322
G. Secchi
Fig. 1 Mechanism of protein-surfactant complex.
and the formation of excess positive or negative charge causes
additional osmotic pressure, leading to swelling of the matrix
and increased permeability. Adding protein derivatives to
cleansing formulations can reduce their adverse effects by
forming complexes (
Fig. 1
) with surfactants within the
detergent formulation, which produces larger micelles and
consequently lowers the CMC of the system.
2
ingredients for creating a suitable environment for healthy skin
and hair because of their ability to bind water with the horny
layer skin and its annexes. Supplementary scientific investiga-
tions were conducted on the binding properties of proteins and
peptides to skin and hair, and their potential role as hair
conditioning agents was suggested in following years and at
the beginning of the 1960
s. Proteins were considered useful
for imparting gloss, softness, and manageability because of
their substantivity, and hydrolyzed protein was proposed for
permanent waving treatments to prevent damage to hair fibres
because of their amphoteric and buffering properties.
5
Most protein derivatives used for cosmetic purposes are
obtained from simple proteins (fibrous and globular),
whereas conjugated proteins (proteoglycans and nucleopro-
tein derivatives) are used far less frequently. Proteins from
both animals (mammals, fish) and plants (angiosperms)
could be used for the formulation of cosmetic ingredients;
proteins obtained from lower organisms (algae, fungi) have
been considered only recently.
6
Availability and the
economy have been the principal criteria for the selection
of the protein sources. However, since the early 1980
’
Proteins in cosmetics
Direct information on the ancient use of protein materials
(cereal flours, animal blood, milk, and egg whites) for
cosmetic purposes is available from all great ancient
civilizations. The spontaneous and practical use of protein
substances (which, with no fundamental modifications,
presently are used and appreciated in modern cosmetology)
includes migrant Eritrean shepherds' use of camel milk to
clean skin and hair, Cleopatra's legendary use of donkey
milk, and Hokkaido island fishers' use of soy flour to prepare
facial masks, and so forth. The first rational use of proteins in
cosmetics dates back the 1950
s,
bovine spongiform encephalopathy epidemiology, conse-
quent health authority regulations, and speculation of
advertising have moved the consumer association against
the use of animal-derived ingredients, which allowed
vegetable protein derivatives to become more important.
’
s.
The beneficial effects of using protein-rich substances in
formulations of various topical applications are recognized
by many authors.
3,4
Proteins quickly were considered useful
’
Role of protein in cosmetics
323
Soluble native protein or soluble
protein hydrolyzed?
of the peptide bond with a 3-step mechanism. The specific
interaction of the enzyme with the side chains of adjacent
amino acids with formation of an activated protease-protein
complex is the base of enzymatic hydrolysis and should make
it possible control and determine most of the molecular
features of the resulting peptides.
To make proteins suitable for use in water-based
cosmetics, it is necessary to convert them into a soluble
form, which is easier to manipulate and is more practical for
formulating purposes. This form is obtained by the hydrolysis
procedure, ie, by cleavage of the protein macromolecule by
disruption of some of the peptide bonds. Cutting native
proteins into smaller pieces with water and a catalyst will
produce water soluble peptides (more pieces of proteins) that
could have useful cosmetic effects. It is important to
distinguish hydrolyzed protein from simple protein pieces.
The surprising differences make it possible to observe and test
their cosmetic performances. A very clear example is the
comparison between the cosmetic activity of soluble native
collagen and hydrolyzed collagen, which is presented often as
soluble collagen or other more fantastic adjectives (fish
collagen, native collagen precursor, etc).
There are also different cosmetic properties that are
strongly dependent of the molecular structure between
hydrolyzed proteins. The number, type, and sequence of
the 20 basic amino acids that compose all natural proteins are
the factors that determine all of their biological properties.
Hydrolyzed proteins are made of the same 20 amino acids,
and the sometimes striking differences (quantitative and
qualitative differences and effects on the skin and hair) are
related to the number, type, and sequence of the constituent
amino acids. Proteolytic enzymes (special proteins obtained
from animal, vegetable, and microbial sources) are able to
catalyze the protein cleavage by lowering the energy barrier
Protein efficacy
Peptide hydrophobicity
7
(
Fig. 2
) is the critical parameter
for cosmetic efficacy, and this peculiarity depends on its
amino acid composition (ie, the relative amount and
lipophilicity of nonpolar residues in the molecule). For
hydrolyzed protein, a theoretical relationship between
molecular size, location of hydrophobic residues along the
protein chain, and actual hydrophobicity has been observed.
Considering that proteolysis with enzymes that have
different specificity leads to peptides with different
locations of hydrophobic/hydrophilic amino acids, the
hydrophobicity level of protein hydrolysates may, to a
certain extent, be planned by selection of a particular
enzyme or enzyme pool and reaching a certain degree of
hydrolysis. The relationship of enzyme specificity to
molecular size and hydrophobicity of hydrolyzed peptides
is illustrated in
Fig. 2
.
Since the hydrophobicity of peptides influences many of
their properties that have cosmetic relevance (substantivity to
hair and skin, tenside binding capacity, foaming and emul-
sifying performance, interaction with radical species, and
solubility), there is a chance to determine their functionalities
Fig. 2
Relationship between the peptide character and the cosmetic efficacy.
324
G. Secchi
by properly managing their manufacturing process. Enzymatic
hydrolysis allows protein cleavage to occur at pH values close
to neutrality and temperatures approaching those of living
beings, with the important advantage of preventing possible
degradation of amino acids and formation of unsafe by-
products. Such mild process conditions preserve the thiol
groups of cysteine.
Apart from the unknown effects of the no-physiological
molecule that the chemical hydrolysis of proteins could
produce, loss of cysteine, serine, and other amino acids also
occurs, which impairs the keratin binding capacity of the
resulting peptides. Many of the interactions of protein
substances with skin and hair and other molecules present in
cosmetic products are of ionic nature; consequently, the
isoelectric point and pH of the medium play a fundamental
role on their cosmetic effects.
The isoelectric point of a peptide occurs at the pH where
the number of protons combined with basic groups equals the
number of protons liberated from acid groups. Mild
enzymatic process prevents deamidation of glutamine and
asparagine, respectively, to glutamic and aspartic acid.
Glutamine and asparagine are more able to link skin/hair
keratin, because their isoionic values are far higher than
related acids.
masks, where transitory moisturization, increased, skin
smoothness, and shine are obtained; or silk powder that is
produced with finely ground purified silk fibroin, which can
be used in anhydrous decorative preparations.
Native proteins and hydrolysates with high molecular
weight generally are preferred in skin care applications for
their film-forming properties. Soluble collagen and its
partially deamidated derivative (Desamidocollagen) are
traditional examples. These particular big molecules are
able to form a continuous colloidal film on the skin
surface, giving a smooth feeling and softness.
8
It is
important to avoid exposing these proteins to heat and
denaturing agents, because (1) the filming properties of
these substances are determined mainly by the length of
the molecules, (2) the hydrating effect of these substances
is related to the high number of exposed hydrogen binding
sites available for linking water, and (3) the properties of
these substances is determined by their conformation in
the triple helix structure. For this reason, proteins usually
are added after emulsification and after the batch has
cooled to a temperature at least 3-5° below the melting
temperature of the molecule (about 35°C for native
soluble collagen, 42°C for desamidocollagen and 24°C
for fish collagen).
9
Formulation highlights
International Nomenclature Cosmetic
Ingredient name
1) Avoid combining of protein derivatives of different
sources or manufacturers; the functionalities of
proteins do not always accumulate with each other
and sometimes mutual inactivation occurs.
2) Refuse chemically hydrolyzed proteins if a lot of
useless dehydrating salts are not needed; unnatural
amino acids are not wanted, but functional and reactive
disulphide bonds are needed.
3) Formaldehyde released from donor preservatives
can be consumed by condensation with free amino
groups of peptides, so avoid using HCHO donors in
formulations, or keep the pH as low as possible to
make a careful challenge test on the finished product.
4) Avoid combinations with some vegetable extracts
containing tannins and other polyphenol derivatives
(rathany, tormentil, and witch hazel), because they can
form insoluble aggregates with large peptides.
5) Insoluble aggregate can be formed by the combination
of large polyanions like hyaluronic acid and cellulose
gum; quaternized guar may precipitate proteins with a
net negative charge.
At this point, it is necessary to emphasize that protein
hydrolysates with the same International Nomenclature
Cosmetic Ingredient name, may have different efficacy.
The substantivity of protein hydrolysates of the same origin
increases with increased hydrophobicity, decreased molecu-
lar size, and increased isoelectric point. Unfortunately it is
not always easy to distinguish an enzymatic protein
derivative from a chemical one. Chemical proteins are
usually rich in inorganic salts, darker in color, and have a
stronger (bitter) smell. The presence of unnatural amino
acids (lysinoalanine,
-
aminoalanine) or a high percentage of cysteic acid are
much more significant indicators that result from the strong
conditions involved in chemical hydrolysis.
lanthionine, ornitoalanine, and
β
Practical use of proteins in cosmetic products
Protein derivatives are used in a variety of skin care and
makeup formulations. Soluble protein ingredients are
appropriate for almost all type of cosmetic forms (emulsions,
lotions, gels, and powders). Insoluble proteins also are used
in particular applications. Examples of these applications
include: fibrous insoluble collagen (obtained by liophiliza-
tion of aqueous dispersions of the native protein) in facial
References
1. Dickerson RE, Geis I. The structure and action of proteins. Verlag
Chemie GmbH, Weinheim; 1971. p. 1-19.
2. Teglia A, Secchi GF. Evaluation of the protective efficacy of proteins
and mild tensides against
the adverse cutaneous effects of anionic
Role of protein in cosmetics
325
detergents by means of transepidermal water loss (TEWL) and
profilometric measurements XVIII IFSCC Congress, Venezia, vol. 4
P073; 1994. p. 662-80.
3. Turowski A, Adlmann-Grill BC. Substantivity to hair and skin of 125
–
labelled collagen hydrolysates under application simulating conditions.
International Journal of Cosmetic Science vol. 7 1985;7:71-4.
4. Teglia A, Mazzola G, Secchi GF. Relationship between chemical
characteristics and cosmetic properties of protein hydrolysates. XVII
IFSCC Congress, Yokoama, vol. 2 A207; 1992. p. 515-68.
5. Kelisema Srl, House document Bulletins 2003.
6. Adler-Nissen J. Enzymatic hydrolysis of food proteins. London: Elsevier
Science Publishing Co., Inc.; 1986.
7. Bigelow CC, Channon M. Hydrophobicities of amino acids and proteins.
Handbook of biochemistry and molecular biology. 3rd ed. New York:
CRC Press; 1976. p. 209-43.
8. Ozawa T. Functional Cosmetology (Substantiation of cosmetics
efficacy), Tokyo: Yakuji Nippo Ltd; 2003.
9. Agache P, Humbert P. Measuring the skin. Berlin: Springer Ed; 2004.
zanotowane.pl doc.pisz.pl pdf.pisz.pl hannaeva.xlx.pl
, 321
–
325
26
Role of protein in cosmetics
Gianfranco Secchi
⁎
KELISEMA Srl, Via Urago, 13/B, 22038 Tavernerio (CO), Italy
Abstract Many authors recognize the beneficial effects of using protein-rich substances in formulations
of various topical applications. Proteins quickly were considered useful ingredients for creating a
suitable environment for healthy skin and hair because of their ability to bind water with the horny layer
of skin and its annexes. Most protein derivatives that are used for cosmetic purposes are obtained from
simple proteins, whereas conjugated proteins are used far less frequently. In this article, the role and
efficacy of proteins used in cosmetics are reported and discussed.
© 2008 Elsevier Inc. All rights reserved.
Preliminary
(hydration), Cutometer
(elasticity), Tewameter
(TEWL),
and Visioscan VC98 (SELS).
of
primary importance") play dominant roles in almost all
biological processes in living beings. Principal functions are:
enzyme catalysis, transfer and accumulation of small
molecules and ions, coordinated movement, mechanical
support, immunity protection, production and transmission
of nervous impulses, and control of growth and differentia-
tion.
1
Thus, the importance of protein use in each kind of
cosmetic product is easy to understand.
The target of the finished product could be whether the
skin, hair, or both lose their main component (proteins) in
everyday situations. In addition, it is well known that some
of the raw materials used in cosmetic formulations interact
with the skin barrier and are responsible for the modification
(mostly weakening) of the horny layer, which compromises
the skin's hydration, elasticity, firmness and softness.
Today all of this skin damage is easy to analyze and
control with different, well known, and internationally
approved skin measurement devices,
Proteins (from the Greek word proteins, which means
“
Surfactant skin irritation
The mechanisms of the adverse effects produced by
surfactants upon contact with skin and hair are not elucidated
fully, but there is general agreement that the adsorption and
interaction of their molecules to the keratin of the stratum
corneum and hair cuticle is the initial step when determining
tissue damage. Only monomeric surfactant can penetrate
when the hydrated micelles are too large to enter the tight
network of keratin fibres; thus, the concentration of tenside
monomers (and hence the critical micelle concentration
[CMC]) should be related to the skin and hair damage. Once
surfactant monomers or small aggregates initially attach to
the keratin surface, additional events and transformations
may take place. This partial denaturizing effect is based on a
combination of the following mechanisms: the hydrocarbon
tail of the surfactants penetrate the polar regions of the
keratin, replacing the conformation-stabilizing hydrophobic
interactions by ligand-segment interactions; the ionic head of
the surfactant produces attraction-repulsion forces on the
charged groups of the keratin, disordering its architecture;
like Corneometer
⁎
Tel.: +39 031 427746; fax: +39 031 427745.
E-mail address:
.
URL:
.
0738-081X/$
–
see front matter © 2008 Elsevier Inc. All rights reserved.
doi:
322
G. Secchi
Fig. 1 Mechanism of protein-surfactant complex.
and the formation of excess positive or negative charge causes
additional osmotic pressure, leading to swelling of the matrix
and increased permeability. Adding protein derivatives to
cleansing formulations can reduce their adverse effects by
forming complexes (
Fig. 1
) with surfactants within the
detergent formulation, which produces larger micelles and
consequently lowers the CMC of the system.
2
ingredients for creating a suitable environment for healthy skin
and hair because of their ability to bind water with the horny
layer skin and its annexes. Supplementary scientific investiga-
tions were conducted on the binding properties of proteins and
peptides to skin and hair, and their potential role as hair
conditioning agents was suggested in following years and at
the beginning of the 1960
s. Proteins were considered useful
for imparting gloss, softness, and manageability because of
their substantivity, and hydrolyzed protein was proposed for
permanent waving treatments to prevent damage to hair fibres
because of their amphoteric and buffering properties.
5
Most protein derivatives used for cosmetic purposes are
obtained from simple proteins (fibrous and globular),
whereas conjugated proteins (proteoglycans and nucleopro-
tein derivatives) are used far less frequently. Proteins from
both animals (mammals, fish) and plants (angiosperms)
could be used for the formulation of cosmetic ingredients;
proteins obtained from lower organisms (algae, fungi) have
been considered only recently.
6
Availability and the
economy have been the principal criteria for the selection
of the protein sources. However, since the early 1980
’
Proteins in cosmetics
Direct information on the ancient use of protein materials
(cereal flours, animal blood, milk, and egg whites) for
cosmetic purposes is available from all great ancient
civilizations. The spontaneous and practical use of protein
substances (which, with no fundamental modifications,
presently are used and appreciated in modern cosmetology)
includes migrant Eritrean shepherds' use of camel milk to
clean skin and hair, Cleopatra's legendary use of donkey
milk, and Hokkaido island fishers' use of soy flour to prepare
facial masks, and so forth. The first rational use of proteins in
cosmetics dates back the 1950
s,
bovine spongiform encephalopathy epidemiology, conse-
quent health authority regulations, and speculation of
advertising have moved the consumer association against
the use of animal-derived ingredients, which allowed
vegetable protein derivatives to become more important.
’
s.
The beneficial effects of using protein-rich substances in
formulations of various topical applications are recognized
by many authors.
3,4
Proteins quickly were considered useful
’
Role of protein in cosmetics
323
Soluble native protein or soluble
protein hydrolyzed?
of the peptide bond with a 3-step mechanism. The specific
interaction of the enzyme with the side chains of adjacent
amino acids with formation of an activated protease-protein
complex is the base of enzymatic hydrolysis and should make
it possible control and determine most of the molecular
features of the resulting peptides.
To make proteins suitable for use in water-based
cosmetics, it is necessary to convert them into a soluble
form, which is easier to manipulate and is more practical for
formulating purposes. This form is obtained by the hydrolysis
procedure, ie, by cleavage of the protein macromolecule by
disruption of some of the peptide bonds. Cutting native
proteins into smaller pieces with water and a catalyst will
produce water soluble peptides (more pieces of proteins) that
could have useful cosmetic effects. It is important to
distinguish hydrolyzed protein from simple protein pieces.
The surprising differences make it possible to observe and test
their cosmetic performances. A very clear example is the
comparison between the cosmetic activity of soluble native
collagen and hydrolyzed collagen, which is presented often as
soluble collagen or other more fantastic adjectives (fish
collagen, native collagen precursor, etc).
There are also different cosmetic properties that are
strongly dependent of the molecular structure between
hydrolyzed proteins. The number, type, and sequence of
the 20 basic amino acids that compose all natural proteins are
the factors that determine all of their biological properties.
Hydrolyzed proteins are made of the same 20 amino acids,
and the sometimes striking differences (quantitative and
qualitative differences and effects on the skin and hair) are
related to the number, type, and sequence of the constituent
amino acids. Proteolytic enzymes (special proteins obtained
from animal, vegetable, and microbial sources) are able to
catalyze the protein cleavage by lowering the energy barrier
Protein efficacy
Peptide hydrophobicity
7
(
Fig. 2
) is the critical parameter
for cosmetic efficacy, and this peculiarity depends on its
amino acid composition (ie, the relative amount and
lipophilicity of nonpolar residues in the molecule). For
hydrolyzed protein, a theoretical relationship between
molecular size, location of hydrophobic residues along the
protein chain, and actual hydrophobicity has been observed.
Considering that proteolysis with enzymes that have
different specificity leads to peptides with different
locations of hydrophobic/hydrophilic amino acids, the
hydrophobicity level of protein hydrolysates may, to a
certain extent, be planned by selection of a particular
enzyme or enzyme pool and reaching a certain degree of
hydrolysis. The relationship of enzyme specificity to
molecular size and hydrophobicity of hydrolyzed peptides
is illustrated in
Fig. 2
.
Since the hydrophobicity of peptides influences many of
their properties that have cosmetic relevance (substantivity to
hair and skin, tenside binding capacity, foaming and emul-
sifying performance, interaction with radical species, and
solubility), there is a chance to determine their functionalities
Fig. 2
Relationship between the peptide character and the cosmetic efficacy.
324
G. Secchi
by properly managing their manufacturing process. Enzymatic
hydrolysis allows protein cleavage to occur at pH values close
to neutrality and temperatures approaching those of living
beings, with the important advantage of preventing possible
degradation of amino acids and formation of unsafe by-
products. Such mild process conditions preserve the thiol
groups of cysteine.
Apart from the unknown effects of the no-physiological
molecule that the chemical hydrolysis of proteins could
produce, loss of cysteine, serine, and other amino acids also
occurs, which impairs the keratin binding capacity of the
resulting peptides. Many of the interactions of protein
substances with skin and hair and other molecules present in
cosmetic products are of ionic nature; consequently, the
isoelectric point and pH of the medium play a fundamental
role on their cosmetic effects.
The isoelectric point of a peptide occurs at the pH where
the number of protons combined with basic groups equals the
number of protons liberated from acid groups. Mild
enzymatic process prevents deamidation of glutamine and
asparagine, respectively, to glutamic and aspartic acid.
Glutamine and asparagine are more able to link skin/hair
keratin, because their isoionic values are far higher than
related acids.
masks, where transitory moisturization, increased, skin
smoothness, and shine are obtained; or silk powder that is
produced with finely ground purified silk fibroin, which can
be used in anhydrous decorative preparations.
Native proteins and hydrolysates with high molecular
weight generally are preferred in skin care applications for
their film-forming properties. Soluble collagen and its
partially deamidated derivative (Desamidocollagen) are
traditional examples. These particular big molecules are
able to form a continuous colloidal film on the skin
surface, giving a smooth feeling and softness.
8
It is
important to avoid exposing these proteins to heat and
denaturing agents, because (1) the filming properties of
these substances are determined mainly by the length of
the molecules, (2) the hydrating effect of these substances
is related to the high number of exposed hydrogen binding
sites available for linking water, and (3) the properties of
these substances is determined by their conformation in
the triple helix structure. For this reason, proteins usually
are added after emulsification and after the batch has
cooled to a temperature at least 3-5° below the melting
temperature of the molecule (about 35°C for native
soluble collagen, 42°C for desamidocollagen and 24°C
for fish collagen).
9
Formulation highlights
International Nomenclature Cosmetic
Ingredient name
1) Avoid combining of protein derivatives of different
sources or manufacturers; the functionalities of
proteins do not always accumulate with each other
and sometimes mutual inactivation occurs.
2) Refuse chemically hydrolyzed proteins if a lot of
useless dehydrating salts are not needed; unnatural
amino acids are not wanted, but functional and reactive
disulphide bonds are needed.
3) Formaldehyde released from donor preservatives
can be consumed by condensation with free amino
groups of peptides, so avoid using HCHO donors in
formulations, or keep the pH as low as possible to
make a careful challenge test on the finished product.
4) Avoid combinations with some vegetable extracts
containing tannins and other polyphenol derivatives
(rathany, tormentil, and witch hazel), because they can
form insoluble aggregates with large peptides.
5) Insoluble aggregate can be formed by the combination
of large polyanions like hyaluronic acid and cellulose
gum; quaternized guar may precipitate proteins with a
net negative charge.
At this point, it is necessary to emphasize that protein
hydrolysates with the same International Nomenclature
Cosmetic Ingredient name, may have different efficacy.
The substantivity of protein hydrolysates of the same origin
increases with increased hydrophobicity, decreased molecu-
lar size, and increased isoelectric point. Unfortunately it is
not always easy to distinguish an enzymatic protein
derivative from a chemical one. Chemical proteins are
usually rich in inorganic salts, darker in color, and have a
stronger (bitter) smell. The presence of unnatural amino
acids (lysinoalanine,
-
aminoalanine) or a high percentage of cysteic acid are
much more significant indicators that result from the strong
conditions involved in chemical hydrolysis.
lanthionine, ornitoalanine, and
β
Practical use of proteins in cosmetic products
Protein derivatives are used in a variety of skin care and
makeup formulations. Soluble protein ingredients are
appropriate for almost all type of cosmetic forms (emulsions,
lotions, gels, and powders). Insoluble proteins also are used
in particular applications. Examples of these applications
include: fibrous insoluble collagen (obtained by liophiliza-
tion of aqueous dispersions of the native protein) in facial
References
1. Dickerson RE, Geis I. The structure and action of proteins. Verlag
Chemie GmbH, Weinheim; 1971. p. 1-19.
2. Teglia A, Secchi GF. Evaluation of the protective efficacy of proteins
and mild tensides against
the adverse cutaneous effects of anionic
Role of protein in cosmetics
325
detergents by means of transepidermal water loss (TEWL) and
profilometric measurements XVIII IFSCC Congress, Venezia, vol. 4
P073; 1994. p. 662-80.
3. Turowski A, Adlmann-Grill BC. Substantivity to hair and skin of 125
–
labelled collagen hydrolysates under application simulating conditions.
International Journal of Cosmetic Science vol. 7 1985;7:71-4.
4. Teglia A, Mazzola G, Secchi GF. Relationship between chemical
characteristics and cosmetic properties of protein hydrolysates. XVII
IFSCC Congress, Yokoama, vol. 2 A207; 1992. p. 515-68.
5. Kelisema Srl, House document Bulletins 2003.
6. Adler-Nissen J. Enzymatic hydrolysis of food proteins. London: Elsevier
Science Publishing Co., Inc.; 1986.
7. Bigelow CC, Channon M. Hydrophobicities of amino acids and proteins.
Handbook of biochemistry and molecular biology. 3rd ed. New York:
CRC Press; 1976. p. 209-43.
8. Ozawa T. Functional Cosmetology (Substantiation of cosmetics
efficacy), Tokyo: Yakuji Nippo Ltd; 2003.
9. Agache P, Humbert P. Measuring the skin. Berlin: Springer Ed; 2004.