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Hydrolysed proteins in cosmetic production, part II

  • Dr Seidel foundation Warsaw Poland
  • Higher School of Engineering and Health
12 SÖFW-Journal Wydanie Polskie | 1 | 4-2008
M. Ścibisz, J. Arct*, K. Pytkowska
Protein hydrolysates
in cosmetics production, part II
Key words: skin care, hair care, cell growth stimulation, undesired effect, modified hydrolysed proteins,
cortex damages. Long-term and fre-
quent exposition to damaging factors
and inappropriate hair care entails cuti-
cle structure alterations manifested by
worsen hair appearance.
Studies concerning factors, which influ-
ence the proteins substantivity, such as
time of contact, concentration, hair con-
dition (normal and bleached hair) were
carried out. It was stated, that in case of
both healthy and bleached hair, sorp-
tion of peptides on the surface occurs
mainly during the first 15 minutes of
treatment by water solution. After this
period increase in quantity of adsorbed
peptides is much slower. Also quantity
of bounded proteins and their hy-
drolysates clearly increased as hair con-
dition worsened. Surprisingly, this de-
pendence was limited – hair bleached
twice adsorbed much more polypep-
tide molecules than hair after single
bleaching. Further damage caused by
repeated application of bleaching agent
didn’t affect the adsorption level. Sorp-
tion of polypeptides wasn’t also influ-
enced by their concentration (in range
between 5 and 20%).
Similar results were obtained during
studies concerning substantivity of col-
lagen hydrolysates with various molec-
ular weights. In case of these experi-
ments, method based on hydroxypro-
line (amino acid characteristic for colla-
gen) assay was used. It was revealed,
that absorption of peptides increases si-
multaneously with hair damage. At the
on proteins or their hydrolysates chem-
ical and physicochemical properties and
in some cases (i.e. during damaged hair
treatment) also on the state of the ad-
sorbing surface. In the event of proteins,
term “substantivity” first of all concerns
ability to form weak or strong bonds
with keratin of the stratum corneum or
hair cuticle. In case of protein molecules
with molecular weights lower than 3000
Da barely few studies confirmed their
ability to penetrate deeper areas of skin
(dermis) and hair (cortex). Experiment
which revealed, that peptides can easily
penetrate cuticle and tends to accumu-
late in cortex were carried out in the 70-
ties. In this study quantity of peptides
was determined by detection technique
based on fragmentary ninhidrine stain-
ing of considered hair. It should be no-
ticed that this assay is characterized by
very low precision. Hence, credibility of
obtained results seems to be question-
Human hair (Fig. 1) is composed of two
main layers: outer shield containing
high quantities of sulfur amino acids and
cortex (60 – 90% of the fiber) responsi-
ble for mechanical properties of the hair.
Empty core (medulla) is not always pre-
sent - it usually appears in thick hairs.
Hair ending and hair root are regiments
where medulla is not observed. Sub-
stances used for hair treatments (oxi-
dants, alkalies), environmental factors
(UV radiation, alkaline pollutions), and
friction or bending create cuticle and
Cosmetic properties of proteins
and their hydrolysates
Proteins have been used in cosmetics
from time immemorial, mainly in form of
plant or animal extracts. Nevertheless,
just 40 years ago first hydrolysates of iso-
lated proteins were introduced. Nowa-
days, they belong to the most often
used group of active ingredients, pri-
marily for hair care and top quality
cleansing products.
Typology of available hydrolysatesis var-
ious, with regard to source of their origin
and diversity of production processes.
However, there is a strong dependence
between their cosmetic activity and
physicochemical properties, such as av-
erage molecular weight, charge or hy-
Many conducted studies concerning
cosmetic activity of proteins and their
hydrolysates revealed, that the most im-
portant feature determining their effec-
tiveness is substantivity to the surface of
the skin and hair.
The outermost layer of skin and hair is
built of fewer or more compact keratin
structures. As a result of non-covalent in-
teractions, during treatment with pro-
teins and their hydrolysates water solu-
tions, layer of adsorbed polypeptides is
formed on the surface. Its properties and
strength of the force which keeps it con-
nected with the surface strictly depends
14 SÖFW-Journal Wydanie Polskie | 1 | 4-2008
Fig. 1 Cross-section of the hair shaft
amined. Tested hydrolysates were ob-
tained from both animal and plant
sources; hydrolysates from following
materials were used: collagen, keratin,
elastin, wheat and corn gluten. Peptides
obtained from keratin demonstrated
high substantivity, higher in compas-
sion to hydrolysates fro other animal and
plant sources. As a result of conducted
studies such order of hydrolysed pro-
teins with respect to decreasing sub-
stantivity has been proposed:
keratin > wheat gluten > collagen
In case of elastin hydrolysates obtained
results were ambiguous, whereas small
quantity of assayed samples for corn hy-
drolysates did not allow placing it in pre-
sented line. For compared hydrolysates
received from the same protein and
characterized by the same isoelectric
point (pI) value, substantivity increased
in conjunction with decreasing molecu-
lar weight. Additionally, absorption of
peptides especially from LMW hy-
dolysate fractions, was preferred both
for damaged and healthy hair. Thus re-
sults confirmed that substantivity de-
pends on hydrophobicity. The higher
hydrophobicity of the peptide the
smaller its effective size in the water so-
lutions. It is caused by forming such
shape of the structure, thanks to which
peptide reduces to minimum its contact
with water molecules. As a result, small
peptide molecules much easier ap-
As a result following conclusions were
increase of the polypeptides con-
centration causes practically rectilin-
ear growth of adsorbed substances
quantity, this dependence is also
true for concentration higher than
5%, what is clearly not in conformity
with previous results,
type of cosmetic vehicle (water,
shampoos with various formula-
tions) and conditions of its usage
have influence on the peptides sub-
stantivity to hair,
adsorption is higher for damaged
than for healthy hair. Dependence is
true only in case of low concentra-
tion of peptides and short time of ap-
peptides with molecular weights in
range 7500 – 15000 Da demonstrate
the highest substantivity,
hydrolysates with the lowest value of
isoelectric point show the highest
Part of these conclusions confirms re-
sults obtained in previous studies. How-
ever, there are some differences espe-
cially in matter of substantivity and mol-
ecular weight of hydrolysates depen-
In order to evaluate relationship be-
tween peptide structure and its ability to
bind with hair keratin, 20 hydrolysates
with various molecular weights were ex-
end of the trial healthy hair contained
about 0.02% of the peptides, while
bleached hair 0.2% and hairs additional-
ly after permanent waving contained
nearly 3% of polypeptides. Hydrolysates
with low molecular weight showed
maximum substantivity.
Other experiment was conducted on
the human skin. Surface of the skin was
treated for 10 minutes with 9% solution
of tested hydrolysate (m.w. 2000 Da).
Next, using hydroxyproline assay con-
tent of the collagen hydrolysate in each
layer of stripped skin was estimated. Ex-
periment revealed, that collagen pep-
tides were present in the first 6 layers (21
verified) of stratum corneum. In layers 1
to 3 content of collagen amounted to
2.78µg/cm2, while in layers 4 to 6 only
0,33µg/cm2. In comparison, control
probe in layers 1-3 contained
0.15µg/cm2of collagen peptides.
Influence of the pH on the collagen hy-
drolysate substantivity to hair after
bleaching and permanent waving (hy-
drogen peroxide, ammonium thiogly-
colate, sodium bromate) was also inves-
tigated. It was observed, that absorption
is the highest in neutral pH (7.0). Maxi-
mum substantivity in alkaline pH was
observed only in the event of hair pre-
treated with ammonium thioglycolate.
It was also found, that in case of hair pre-
treated with hydrogen peroxide and
ammonium thioglycolate, adsorption of
peptides significantly increases by the
first 5-10 minutes in the course of action.
Conducted studies concerning substan-
tivity of peptide fractions with various
molecular weights, which were isolated
from hydrolysates available on market
proved, that fractions with m.w. about
1000 Da showed the strongest adsorp-
tion. Additionally, higher substantivity
was observed for hair after bleaching
and permanent waving than for only
bleached hair. Again, increasing absorp-
tion with increasing hair damage was
In order to investigate substantivity of
collagen hydrolysates to the surface of
the skin and hair with respect to applied
concentration, type of cosmetic vehicle,
hair condition and time of product ap-
plication experiments were carried out.
Peptide quantity determination was
based on their labeling with 125I isotope.
SÖFW-Journal Wydanie Polskie | 1 | 4-2008 15
properties and irritation potential with
respect to the chain length of the
polypeptide was investigated. It was
stated, that molecules containing in
their structure 750 Da chain have five
times lower irritancy potential than
those containing 500 Da chain. Molecu-
lar weight of proteins’chain higher than
750 Da insignificantly lowered irritation
potential of surfactant. On the other
hand, molecules containing short
chains had the best cleansing proper-
ties. Presence of chain with higher mol-
ecular weight than 750 Da significantly
reduced cleansing properties. It was al-
so observed, that combination of an-
ionic surfactant (Sodium Lauryl Sulfate,
SLS) and protein derivative (20% of the
mixture) reduced irritation potential by
one third in comparison to solution con-
taining only SLS. Other trial revealed,
that pure Sodium Laureth Sulfate com-
pletely deactivated enzyme for saccha-
rose, while its combination with protein
derivative in ratio 35 : 65 practically did-
n’t affect this enzyme.
Many studies concerning influence of
proteins and their derivatives on reduc-
tion of surfactant irritant potential were
conducted. Effectiveness of their ability
to diminish negative activity of surfac-
tants was evaluated among others by
usage of two hydrolysates combination,
characterized by different molecular
weights, 2200 Da (pI=5.1) and 800Da
(pI=5.1). In experiment, surfactants with
pressure, which increases permeabil-
ity of the stratum corneum and hairs
Addition of proteins is one of the most
examined and effective method of epi-
dermis protection from negative effects
caused by surfactants. Activity of pro-
teins and their derivatives may be due
lowering the CMC value by surfac-
tant molecules complexing (ionic
bonds, hydrogen, hydrophobic and
mixed micelle formation), which re-
duces quantity of free, unbounded
monomers in the solution; surface
activity remain unchanged. Sorp-
tion of surfactant molecules on the
surface of proteins is shown in
Fig. 2.
binding the protein to skin keratin
by weak, but numerous bonds, ipso
facto causing formation of protec-
tive colloidal layer which is able to
bind aggressive chemical sub-
Protective properties of proteins and
their hydrolysates, preventing skin irrita-
tion and hair damaging, were evaluated
in in vitro and in vivo tests carried out in
human and in animals. Initially, deriva-
tives of proteins were used – fatty acids
condensates, utilized as a mild surfac-
tants. Dependence of their cleansing
proach to skin and hair keratins’binding
centres and penetrate keratin fibres.
Weak, but meaningful substantivity in-
crease was observed, when isoelectric
point value of particular hydrolysate was
higher. This dependence was clear for
damaged hair (after bleaching or per-
manent waving). It should be noticed,
that two types of wheat hydrolysates
with different pI values (pI1= 3.9 and
pI2=5.6) were compared. Experiment
was carried out in pH = 6.0, hence both
hydrolysates were negatively charged,
same as surface of the hair. Probably, this
could significantly reduce their substan-
Reduction of surfactants’
irritant potential
Frequent and accumulative skin exposi-
tion to the surfactants, especially to an-
ionic, can lead to skin barrier damage
and provoke such adverse effects as:
dryness, roughness, and even irritation.
This phenomenon is caused by surfac-
tant penetration and interaction with
liquid crystal structures of stratum
corneum, as well as cell membranes in
viable epidermis. On the other hand,
hair damages caused by activity of sur-
factants are result of cuticle structure re-
laxing and weakness of its mechanical
When critical micelle concentration
(CMC) is reached, which is characteristic
for particular surfactant and tempera-
ture, large aggregates (micelles) are
formed. Remaining surfactant
monomers present in solution are able
to penetrate keratin structures of skin
and hair.
Anionic surfactants may affect the skin
by following three postulated mecha-
hydrocarbon chain of the surfactant
penetrates through non-polar re-
gions of keratin where it disturbs hy-
drophobic bonds stabilizing proteins
negative charge of surfactant gener-
ates forces causing attraction or re-
pulsion, which interact with charged
fragments of keratin and cause its
structure alteration,
presence of hydrophilic ionic struc-
tures leads to increase of osmotic
Fig. 2 Interaction of surfactant molecules with protein
16 SÖFW-Journal Wydanie Polskie | 1 | 4-2008
soothing properties, available on the
market, were used. They were: Cocami-
dopropyl Betaine and Cocamidopropyl-
Amine Betaine. Similar to proteins, activ-
ity of these compounds is based on in-
teractions with surfactant molecules
and mixed micelle formation. Evaluation
of such parameters as skin hydration
and transepidermal water loss allowed
estimating ability of protein additives to
reduce undesirable effects caused by
Effectiveness was estimated after single
and multiple skin exposition to tested
substances. Results of conducted exper-
iments allowed drawing following con-
influence on TEWL of protein hy-
drolysates is similar to Cocamido-
propyl Betaine and Cocamidopropyl-
Amine Betaine after single skin treat-
ment with surfactant solution,
hydrolysates with high molecular
weight demonstrate higher protec-
tive properties in comparison with
l.m.w. hydrolysed proteins,
there is a slight, but noticeable in-
crease of the skin tolerance in con-
junction with protein concentration
wheat proteins demonstrate synergy
with soothing surfactants.
In case of multiple tests, proteins were
more effective than soothing surfac-
tants. It confirms the fact, that beyond di-
rect interactions with SLS, protein mole-
cules bind with skin keratin forming con-
tinuous barrier which protects the stra-
tum corneum.
Using similar method, effects of colla-
gen, elastin, keratin and wheat gluten
hydrolysates with various molecular
weights were investigated. All tested hy-
drolysates showed ability to reduce irri-
tation potential of SLS. TEWL measure-
ments allowed creating following de-
pendence (decreasing ability to reduce
irritant potential of the surfactant) with
respect to hydrolysates origin:
elastin and gluten > collagen
>> keratin
Results of conducted studies showed
better protection ability of hydrolysates
with higher hydrophobicity and molec-
ular weight.
Other studies concerned ability of hy-
drolysates to interact with Sodium Lau-
ryl Sulfate (SLS). It was demonstrated,
that proteins which are short in sulphur-
containing amino acids show tendency
to bind over 50% more SLS than pro-
teins with ability to form disulfide bonds
(i.e. keratin). CMC values of complexes
formed by protein and tested surfactant
were similar in case of all proteins re-
gardless of their molecular weight.
Hair and skin care
In skin care, proteins and hydrolysed
proteins are used mainly as moisturizing
agents. Polypeptides adsorbed on the
skin surface supplement outer hy-
drophilic skin coat and due to ability of
hydrogen bonds formation they bind
water molecules. Many amino acids
may act as a donors (ie. arginine and
tryptophan) and acceptors (asparagine,
glutamine, serine and threonine) in con-
nection with presence of special groups
localized in the side chains. On the oth-
er hand, depending on the pH value,
acidic (glutamic and aspartic acid) and
alkaline (lysine, tyrosine, histidine)
amino acids play role as hydrogen ac-
ceptors or donors. Highly hydrated lay-
er, which consist of proteins bounded to
the skin surface hampers diffusion and
prevents water evaporation. Hy-
drolysates with low molecular weight
may form strongly adsorbed monomol-
ecular layer, which is difficult to remove.
Large molecules tend to form weakly
anchored film, but with greater ability to
bound water molecules. Hence, HMW
polypeptides are more often used as
moisturizing film formers. LMW pep-
tides, on the other hand constitute in-
gredients of products, which require
high substanivity, i.e. designed for hair
regeneration, where peptides after
building in hair keratin restore its prop-
er structure.
Conducted studies confirmed benefi-
cial influence of proteins on the skin hy-
dration. In vivo comparative test using
emulsion containing 5% of the water
soluble collagen and placebo, was car-
ried out. After 10 days of application,
evaluation of each skin layer revealed
significant difference of their thickness
strictly related to the hydration level.
Studies concerning moisturizing prop-
erties of proteins and their hydrolysates
delivered from various physicochemical
forms of cosmetics, such as o/w emul-
sions, gels, water solutions and form
which contained surfactants, were con-
ducted. HMW proteins showed excel-
lent moisturizing properties when used
in o/w emulsions and cleansing prod-
ucts, whereas low molecular acted as a
substances which astringe and tighten
the skin, even the surface and have an-
ti-wrinkle properties. Results of studies
allowed to define advantages of pro-
teins and hydrolysed proteins as cos-
metic ingredients:
they increase elasticity and hydration
level of the skin after application of
leave on (creams) as well as rinse–off
cosmetics (soaps, shampoos),
they improve skin tightness,
they improve skin ability to respond
to the deformation, thus temporary
even wrinkles.
Proteinaceous ingredients are used in
cosmetics for skin care mainly at con-
centration of 0.1 to 2% (Formula-
tions 1-2). Hydrolysed proteins are of-
ten used in combination with other
moisturizing agents, such as glycerin,
sodium lactate, or free amino acids. Po-
lar peptides, first of all constitute ingre-
dients of emulsion water phase. Their
hydrophilic nature permit to suppose
that they stabilize o/w emulsions, due to
increasing viscosity of the external
phase. On the other hand hydrophobic
proteins, characterized by low solubility
might stabilize emulsions, thanks to wa-
ter-oil interface affinity.
Proteins and hydrolysed proteins are
widely applied in hair care cosmetics as
conditioning agents – improving soft-
ness, elasticity, and gloss and hair re-
silience. They are most often used as
main ingredients of shampoos and both
- leave on and rinse off conditioners for
damaged and dry hair. In this kind of for-
mulations their concentration is usually
not higher than 1-2% (Formulations 3-
Proteins play crucial role in bleaching,
SÖFW-Journal Wydanie Polskie | 1 | 4-2008 17
Foam boosting effect
Softness and smoothness to skin and
hair, together with anti-irritating effect
are the main factors determining use of
such ingredients in cosmetic products.
Proteins may also be applied as“techni-
cal function” ingredients (buffering
properties, viscosity control). One of
such function is also foam boosting ef-
fect. Water soluble proteins, as other hy-
drophilic polymers stabilise foams.
Hydrolysed proteins of different origin
(i.e. collagen, elastin, keratin, corn
gluten, and wheat proteins) were stud-
ied regarding their foam boosting activ-
ity. The best effect was obtained for hy-
drolysed wheat proteins (foam height at
approx 100-140mm, with high stability)
with exception of hydrolysate obtained
by means of enzymatic hydrolysis. Hy-
drolysed keratin formed foam with sig-
nificant height, yet unstable. In the 5-8
pH range foam boosting effect was sim-
ilar for various hydrolysed proteins.That
effect was considerable worse in the pH
below 5.
Foam boosting behaviour relied also on
molecular weight, especially in the case
of hydrolysed proteins with low hy-
drophobicity. Such tendency was not
observed for hydrolysed wheat protein.
In the case of hydrolysed collagen foam
boosting effect decreased with molecu-
lar weight reduction.
Modified hydrolysed protein
The significance of proteins and their hy-
drolysates in cosmetics is also reflected
by use of theirs modified derivatives.
Properties of such compound are strict-
ly associated with protein’ part in the
their penetration ability into deeper
parts of skin. That’s why their activity in
these areas seems to be questionable.
On the other hand, in case of low mole-
cular weight peptides penetration
through stratum corneum is possible,
and is supported by alkyl substituents.
Undesired activity
Protein based ingredients are of natural
origin. The same INCI name may used for
substances obtained in different tech-
nological processes. That implicates risk
of irritant activity of these substances.
Safety reports published by the Ameri-
can College of Toxicology classified col-
lagen hydrolysates as non-toxic, sub-
stances with minimal irritant effect (eval-
uated in Draize test), without sensitiza-
tion in guinea-pig test. LD50 value for rats
and mouses was at level of 10-20 grams
of pure protein per kg of the body mass.
Despite of low toxicity of proteins, one
can find studies indicating undesired ac-
tivity of various proteins and their deriv-
atives used in hair care cosmetic prod-
ucts. Such ingredients are obtained from
collagen, elastin, keratin, milk proteins,
wheat, silk and almonds. Hydrolysates of
these proteins showed irritant potential
in 0.5% of examined patients. In studied
groups of hydrolysates the larger group
of undesired reaction in patients, espe-
cially with atopic dermatitis, were ob-
served for collagen derivative (i.e. Hy-
droxypropyl Trimonium Hydrolyzed Col-
lagen). Such reaction was associated
with contact urticaria symptom.
There are as well studies confirmed irri-
tant activities of wheat and bovine hy-
drolysed proteins, used in skin and hair
care products.
permanent waving and hair straighten-
ing products. They haveunique abilit y to
limit undesirable effects of oxidizing and
reducing agents on the hair structure.
Permanent waving is based on disulfide
bonds reduction and formation of a new
bonds determining geometry of fibrils.
Addition of HMW protein hydrolysates,
which are rich in sulfur-containing
amino acids causes formation of cova-
lent bonds between keratin and deliv-
ered in cosmetic polypeptides. As a re-
sult, durable connections are formed,
which reduce damages occurring dur-
ing treatment. Additionally, hydrolysates
which are easily accessible for oxidizing
and reducing agents constitute sub-
strates in side reactions, which normally
occur between mentioned agent and
hair keratin. As keratins plant equivalent
used in these kind of treatments wheat
proteins are mainly used.
Cells growth stimulation
Many publications concerning proteins
and their hydrolysates pay special atten-
tion to their stimuli effect on cells divi-
sions. It was mainly observed in treated
with wheat proteins fibroblasts. Level of
cells divisions increased simultaneously
with extending concentration of the hy-
drolysate (range between 0.01 and
In other study, influence of collagen,
gelatin and hydrolysed collagen
(m.w. < 15000Da) on mouse ker-
atinocytes division was determined. Pro-
liferation was observed during 8 to 20h
of the trial. Significant stimulation was
noticed just after 8h, but only in case of
collagen. Results obtained for hy-
drolysates and gelatin, were compara-
ble with results for control probes.
Effects of conducted studies allow de-
ducing that proteins show activity in
deeper parts of skin, as they stimulate fi-
broblast proliferation. Thus they can de-
lay aging process and improve skin elas-
ticity and firmness. However, advanta-
geous effects on hairs and skin condi-
tion are due to mentioned before
interactions between proteins and pep-
tides with their surfaces. Studies con-
cerning permeability didn’t confirm
Fig. 3 Chlorhydrine with quarterbary nitrogen atom
R=-CH3, n-alkyl group
Formulation 2 Anti hyperpigmentation skin cream
Potassium Palmitoyl Hydrolyzed
Wheat Protein (and) Glyceryl Stearate
(and) Cetearyl Alcohol 10,00
Squalane 12,00
Ethylhexyl Ethylhexanoate 5,00
Cocoglycerides 2,00
Dimethicone 0,50
Aqua Do 100
Potassium Azeloyl Diglycinate 7,00
Prunus Amigdalus var. Dulcis (and)
Hydrolyzed Sweet Almond Protein
(and) Potassium Palmitoyl Hydrolyzed
Wheat Protein 2,50
Avena Sativa (and) Hydrolyzed Oat Protein
(and) Potassium Palmitoyl Hydrolyzed
Oat Protein 2,50
18 SÖFW-Journal Wydanie Polskie | 1 | 4-2008
molecule, but through other, non-pro-
tein part they may demonstrate better
solubility, substantivity, or better foam
boosting effect. Production of protein
derivatives takes quite big part of cos-
metic ingredients and raw materials
One of the most popular, used for 30
years, group of modified hydrolysed
proteins are condensates of proteins
with fatty acids. Protein or hydrolysed
proteins, most often obtained by means
of enzymatic hydrolysis, are N-acetylat-
ed with long chain fatty acids chlorides
in neutral or weak alkaline pH (7-9). Prod-
ucts of that reaction are described as
ones of the mildest surface active
agents. Since theirs irritant potential is
lower than observed one for surfactants
form betaines group, they are use in
shampoos, skin, face cleansing products
and shower gels (Formulations 5-6).
They also indicate a good skin and eyes
tolerance, have very well cleansing and
foam boosting properties, even in hard
water. They are as well far soluble in or-
ganic solvents like ethanol.
Comparing to condensates of proteins
with fatty acids, more important from
the commercial point of view are qua-
ternary protein derivatives. Such com-
pounds are obtained in alkylation reac-
tion of hydrolysed protein with chlorhy-
drine, compound with quaternary nitro-
gen atom (Fig. 3), in alkaline environ-
ment. To increase conditioning effect of
such modified protein, linear chains (12
and more carbon atoms) with lipophilic
properties, are introduced as R alkyl
Isoelectric point of hydrolysed proteins
lies in pH range of 4 to 7. After reaction
yielding quaternary derivative obtain-
ing, isoelectric point value increases to
pH 9-12. Furthermore, quaternary hy-
drolysed proteins indicate positive
charge in whole pH range, while un-
modified hydrolysed proteins bear it on-
ly in pH below the isoelectric point.
Increased cationic character of protein
derivatives increases substantivity of
these compound to both skin and hair
keratin, which in physiological pH indi-
cate total negative charge. Such prop-
erties may be useful in washable prod-
ucts. Quaternary derivatives are used as
conditioning and film-forming agents,
especially in hair care products. They are
compatible with ionic and non-ionic
surfactants; thereby they are easily in-
troduced into shampoo formulation.
One can find studies that showed
cationic derivative of wheat protein
soothing properties of irritant activity of
surfactants. They also decreased irritant
potential formulation in which skin
compatible ingredient such as betaines
were introduced. Furthermore skin
compatibility of quaternary protein de-
rivatives increased with molecular
weight increasing of protein part of
Recently such protein derivatives as sili-
cone copolymers and phosphorylated
derivatives are applied as cosmetic in-
(1)E.D. Goddard, J.V. Gruber; Principles of
polymer science and technology in cos-
metics and personal care; Marcel Dekker,
New York, 1999
(2)V.L. Johnsen; Proteins in cosmetics and toi-
letries; Drug&Cosmetic Industry, 6, p.36,
(3)V.L. Johnsen; Innovation in protein prod-
ucts and technology; Cosmetics&Toi-
letries, 92, 12,p.29, 1977
(4)A. Teglia, G. Mazzola, G. Secchi; Chemical
characteristics and cosmetic properties of
protein hydrolysates; Cosmetics&Toi-
letries, 108, 11, p.56, 1993
(5)J.Arct; Proteiny; Wiadomości PTK, 2, 1, p.17,
(6)U. Griesbach, M. Klingels, V. Homer; Pro-
Formulation 1 Skin tone cream (Sinerga)
Potassium Palmitoyl Hydrolyzed Wheat Protein
(and) Glyceryl Stearate (and) Cetearyl Alcohol 10,00
Ethylhexyl Ethylhexanoate 5,00
Dimethicone 0,50
Aqua Do 100
Phenethyl Alcohol (and) Methylparaben (and)
Propylparaben (and) Glycerin 1,00
Squalane 10,00
Potassium Caproyl Tyrosine 5,00
Algae 2,50
Hydrolyzed Vegetable Protein 1,50
Sodium Carbomer 0,10
Parfum 0,70
Carbomer 0,40
Aminomethyl Propanol 0,05
Disodium EDTA 0,10
Tocopherol (and) Lecithin (and) Citric Acid
(and) Ascorbyl Palmitate 0,05
SÖFW-Journal Wydanie Polskie | 1 | 4-2008 19
teins: classic additives and actives for skin
and hair care; Cosmetics&Toiletries, 113,
11, p.69, 1998
(7)G.Y. Li, S. Fukunaga, K. Takenouchi, F. Naka-
mura; Comparative study of the physio-
logical properties of collagen, gelatin and
collagen hydrolysate as cosmetic materi-
als; International Journal of Cosmetic Sci-
ence, 27, p. 101, 2005
(8)UIImann’s Encyclopaedia of Industrial
Chemistry, Fifth Edition, A22
(9)E.S. Stern. V.L. Johnsen; Studies on the mol-
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tein hydrolysates; Journal of the Societies
of Cosmetic Chemists, 28, 8, p.447, 1977
(10) B.W. Gesslein, R.T. Jones; Kerasol, a new
keratin protein; Cosmetics&Toiletries, 102,
6, p.52, 1987
(11) F. Pasche-Koo, M. Claeys, C. Hauser; Con-
tact urticaria with systemic symptoms
caused by bovine collagen in a hair con-
ditioner; American Journal of Contact Der-
matitis, 1, 1, p.56. 1996
(12) US Patent 4,279,996
(13) 24. E.S. Cooperman, V.L. Johnsen; Pene-
tration of protein hydrolysates into human
hair strands; Cosmetic&Perfumery, 88,
p.19, 1973
(14) S.A. Karjala, RJ. Bouthilet, J.E. Williamson;
Some factors affecting the substantivity of
proteins to hair; Proceedings of Scientific
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p.6. 1966
(15) M.D. Ranganayaki, T.S. Ranganathan, K.S.
Jayaraman; A novel technique for the
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(16) M.D. Ranganayaki, T.S. Ranganathan, K.S.
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(17) S.A. Karjala A. Karier, J.E. Williamson; The
effect of pH on the sorption of collagen –
derived peptides by hair; Journal of the So-
cieties of Cosmetic Chemists, 18, 10, p.599,
Formulation 3 Hair conditioner (Croda)
Quaternium-91 (and) cetrimonium methosulfate
(and) cetearyl alcohol 2,23
Stearyl alcohol 2,00
Cetyl alcohol 0,50
C10-C30 cholesterol/lanosterol esters 1,00
PPG-3 benzyl ether myristate 4,50
PG-hydroxyethyl cellulose steardimonium chloride 0,20
Hydrolyzed silk 1,00
Hydrolyzed wheat protein 1,00
Hydrolyzed vegetable protein PG-propyl silantriol 1,00
Glycerin (and) butylene glycol (and) water
(and) camellia sinensis leaf extract 0,10
Glycerin (and) butylene glycol (and) water
(and) chamomilla recutita (Matricaria) extract 0,10
Glycerin (and) butylene glycol (and) water
(and) hippophae rhamnoides fruit extract 0,10
Phenoxyethanol (and) methyl paraben (and) ethyl paraben
(and) butyl paraben (and) propyl paraben (and) isobutyl paraben 1,00
Aqua 85,27
Formulation 5 Shower gel (Sinerga)
Sodium Laureth Sulfate 25,00
Lauramidopropyl Betaine 6,00
Disodium Cocoamphodiacetate
(and) Sodium Laureth Sulfate 10,00
Disodium Laureth Sulfosuccinate
(and) Sodium Lauryl Sulfoacetate 5,00
Potassium Cocoyl Hydrolyzed Soy Protein 5,00
Caprylyl/Capryl Glucoside 2,50
Linoleamidopropyl Dimethylamine Lactate 2,50
Hydrolyzed Vegetable Protein 2,00
Yucca Schidigera Extract 1,00
Parfum 1,00
Preservative q.s.
Disodium EDTA 0,10
Sodium Chloride 0,50
Aqua Do 100
Formulation 4 Regenerating shampoo (Cognis)
Sodium coco-sulfate 10,81
Coco-glucoside 19,24
Lauryl glucoside (and) stearyl citrate 2,00
Coco-glucoside (and) glyceryl oleate 2,00
Hydrolyzed wheat protein 1,00
Sodium benzoate 0,50
Perfume q.s.
Citric acid (50%) q.s.
Sodium chloride 0,50
Aqua 63,95
Formulation 7 Mild, hair care shampoo (Cognis)
Hydroxypropyl guar hydroxypropyl- trimonium chloride 0,1
Xanthan gum 1,0
Decyl glucoside 30,0
Lauryl glucoside 6,0
Coco-glucoside (and) glyceryl oleate 3,0
Dicaprylyl ether (and) lauryl alcohol 0,5
Laurdimonium hydroxypropyl
hydrolyzed wheat protein 2,0
Sodium benzoate 0,5
Citric acid (50%) q.s.
Aqua 56,9
20 SÖFW-Journal Wydanie Polskie | 1 | 4-2008
Formulation 6 Shower emulsion(Sinerga)
Sodium Laureth Sulfate 30,00
Sodium Laureth Sulfate (and) Cocamide MEA 12,50
Disodium Laureth Sulfosuccinate (and) Sodium Lauryl Sulfoacetate 5,00
Potassium Cocoyl Hydrolyzed Soy Protein 5,00
Caprylyl/Capryl Glucoside 2,50
Potassium Cocoyl Hydrolyzed Oat Protein (and) Glyceryl Stearate 10,00
Cocodimonium Hydroxypropyl Hydrolyzed Wheat Protein 1,00
Hydrolyzed Vegetable Protein 1,50
Almond (Prunus amigdalus var, dulcis) Oil (and) Hydrolyzed Almond Protein
(and) Potassium Palmitoyl Hydrolyzed Wheat Protein 2,50
Aqua Do 100
Preservatives q.s.
Disodium EDTA 0,10
Lauramidopropyl Betaine 1,50
Parfum q.s.
(18) A. Turowski, B.C. Adelmann-Grill; Sub-
stantivity to hair and skin of 125I-labelled
collagen hydrolysates under application
simultaning conditions; International
Journal of Cosmetic Science, 7, p7I, 1985
(19) A.Teglia, G. Secchi; Minimizing the cuta-
neous effects of anionic detergents; Cos-
metics&Toiłetńes, 111, 8, p.61, 1996
(20) R. Pitt-Rivers, F.S.A. Imptombato; The
bindin; of Sodium Dodecyl Sulphate to
various proteins; Biochemical Journal, 109,
p.825, 1968
(21)N.I. Challoner, S.P. Chahal, R.T. Jones; Cos-
metic proteins for skin care; Cosmet-
ics&Toiletries, 112, 12, p.51, 1997
(22)A. Niinimaki:, M. Niinimaki, S. Makinen-
Kiljunen, M. Hannuksela; Contact urticaria
from protein hydrolysates in hair condi-
tioners; Allergy, 53, p.1078, 1998
(23)E.Yarjonen, L. Petman, S. Makinen-
Kiljunen; Immediate contact allergy from
hydrolyzed wheat in a cosmetic cream; Al-
lergy, 55, p.294, 2000
(24)F. Sanchez-Perez, T. Sanz, A. Garcia-Diez;
Allergic contact dermatitis from hy-
drolyzed wheat protein in cosmetic
cream; Contact Dermatitis, 42, p.360, 2000
Authors’ address:
Marta Ścibisz
Academy of Cosmetics
and Health Care
Jacek Arct, PhD
Academy of Cosmetics
and Health Care,
Podwale St. 13, 00-252 Warsaw, Poland
Warsaw University fo Technology,
Faculty of Chemistry
* Email:
Katarzyna Pytkowska
Academy of Cosmetics
and Health Care
... Various ways of reducing the irritant effect caused by anionic surfactants are presented in the literature. Work has mainly focused on the introduction of "mild" surfactants into formulation [11][12][13][14], protein hydrolysates [15,16], hydrophobic substances [17], or polymers [18]. The mechanism of action of such additives is usually related to an increase in micelle size or the formation of appropriate complexes in order to reduce the concentration of free surfactant monomers in the solution. ...
... effect caused by anionic surfactants are presented in the literature. Work has mainly focused on the introduction of "mild" surfactants into formulation [11][12][13][14], protein hydrolysates [15,16], hydrophobic substances [17], or polymers [18]. The mechanism of action of such additives is usually related to an increase in micelle size or the formation of appropriate complexes in order to reduce the concentration of free surfactant monomers in the solution. ...
Full-text available
Liquid soaps are the basic cosmetics used to clean the skin of the hands. Frequent hand washing prevents viral contamination but may damage the skin’s hydro-lipid layer, leading to various types of irritation. Therefore, four liquid soap formulas were developed with three amphoteric surfactants: Cocamidopropyl Betaine (LS II), CocamidopropylHydroxysultaine (LS III), and newly synthesized Evening PrimroseaamidopropylSulfobetaine (LS IV). We evaluated the skin irritating potential (zein number, bovine albumin test) and cytotoxicity (AlamarBlue™, Cell viability, and Cell cycle assays) on HaCaT cell line. We observed lower values of the zein number and bovine albumin tests after adding soaps with surfactants (the highest differences in LS IV) compared to the base soap (LS I). However, LS I and LS II did not differ in cytotoxic assays. Therefore, adding LS III and LS IV seems potentially more dangerous to the cells. However, it should be noted that cells were continuously exposed to liquid soaps for more than 24 h, so its cytotoxic effects after dermal use in humans may be unnoticeable. Concluding, results suggest that the newly synthesized LS IV should improve the safety of liquid hand washing soaps.
... On the contrary, collagen hydrolysates with a higher M w show rather a barrier effect on the skin after topical application of the cosmetic preparation. Such an effect was expressed by the decrease in TEWL due to the formation of a protective film on the skin [25]. The beneficial effects of collagen hydrolysates or peptides on the monitored skin properties were also demonstrated with oral dosing of such products (in the amount of 2.5-5.0 g per day for 2-6 months). ...
Full-text available
Chicken stomachs can be processed into collagen hydrolysate usable in cosmetic products. The aim of the study was to verify the effects of a carbopol gel formulation enriched with 1.0% (w/w) chicken hydrolysate on the properties of the skin in the periorbital area after regular application twice a day for eight weeks in volunteers ageed 50 ± 9 years. Skin hydration, transepidermal water loss (TEWL), skin elasticity and skin relief were evaluated. Overall, skin hydration increased by 11.82% and 9.45%, TEWL decreased by 25.70% and 17.80% (always reported for the right and left area). Generally, there was an increase in skin elasticity, a decrease in skin roughness, as the resonance times decreased by 85%. The average reduction of wrinkles was 35.40% on the right and 41.20% on the left. For all results, it can be seen that the longer the cosmetic gel formulation is applied, the better the results. Due to the positive effect on the quality and functionality of the skin, it is possible to apply the cosmetic gel formulation in the periorbital area. The advantage of the product with chicken collagen hydrolysate is also the biocompatibility with the skin and the biodegradability of the formulation.
... Feathers can be processed by suitable hydrolytic processes into keratin meal, which has good digestibility and is suitable, for example, as a protein additive in animal feed [10][11][12]. Keratin hydrolysates are also used as functional additives in hair and body cosmetics [13,14]. At our workplace, a combined alkaline-enzymatic hydrolysis of hen feathers to low-molecular keratin hydrolysate was designed, which was subsequently tested in cosmetic emulsions for skin care; higher hydration and improved skin barrier function were confirmed in the tested probands [15]. ...
Full-text available
By-products of laying hens represent a promising raw material source with a high collagen content, which is currently not adequately used. The aim of the paper is to prepare gelatins from laying hen paws. The purified collagen raw material was processed by a biotechnological process using the food endoprotease Protamex®. After cleavage of the cross-links in the collagen structure, the gelatin was extracted by a batch process with a stirrer in two extraction steps. The influence of the extraction process on the yield of gelatins and on selected qualitative parameters of gelatins was monitored by two-level factor experiments with three selected process factors. The studied factors were: enzyme dosage (0.2–0.8%), enzyme processing time (24–72 h) and gelatin extraction time (30–120 min). After the first extraction step at 75 °C, gelatin was extracted with a yield of 8.2–21.4% and a gel strength of 275–380 Bloom. In the second extraction step at 80–100 °C, it is possible to obtain another portion (3.3–7.7%) of gelatin with a gel strength of 185–273 Bloom. Total extraction efficiency of gelatins prepared from laying hen collagen is almost 30%. The prepared gelatins are of high quality and, under proper extraction conditions, gelatins with a gel strength above 300 Bloom can be prepared, thus equaling commercial beef and pork gelatins of the highest quality. Biotechnological processing of laying hen collagen into gelatins is environmentally friendly.
... Protein hydrolysates providing mainly di-and tripeptides are superior to intact (whole) proteins and free amino acids to be applied in several areas, such as nutrition [9,10], biotechnology [11,12] and cosmetics industries [13]. Therefore, the production of protein hydrolysates is an option to generate more income for the fish processing plant. ...
Full-text available
PurposeFish waste was studied as a raw material for the simultaneous production of protein hydrolysates, collagen and fish oil. Enzymatic hydrolysis was selected for recovering these by-products with high value-added.Methods Alcalase 2.4 L was used to hydrolyze fish waste in a batch reactor under controlled conditions (180 min, 50 °C and pH 8). The influence of hydrolysis degree on by-products recovery was analyzed for different enzyme and substrate concentrations.ResultsResults suggested that the enzyme/substrate ratio was the main factor controlling the hydrolysis rate. Linear relationships were found between the degree of hydrolysis and the amount of each of the obtained by-products. From these relationships, the amounts of by-products with high added value can be predicted by only knowing the degree of hydrolysis reached. In optimal conditions (DH = 25%), 430 g of protein hydrolysate, 10 g of collagen and 350 g of oil could be obtained from 1000 g of fish waste. The use of fish waste as raw material for by-product fabrication resulted in a 79% reduction of waste disposed to landfill.Conclusion Therefore, this study shows the enzymatic hydrolysis of fish waste as a feasible solution to obtain high value-added products and an alternative to landfilling disposal.Graphic Abstract
... There is evidence that ROS are involved in the process of skin aging, and the topical application of cosmetics with antioxidant properties has certified biological effects on the ROS. 36,37,38,4 Alanine, aspartic acid, phenylalanine, histidine, tyrosine, methionine, cysteine are responsible antioxidant capacity peptides. 39,40 And the glycinin constituted in aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, cysteine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, histidine, lysine and arginine amino acids. ...
Full-text available
INTRODUCTION: Phytocosmetic are gaining increasing attention from consumers who search for alternatives for the maintenance and protection of the skin. This article reports formulation of a phytocosmetic derived from defatted soybean flour, an emulsion base that is hydrolyzed from the glycinin protein (1000 µg/ g). MATERIAL AND METHODS: Test for stability, microbiological control and biological activities,antimicrobial (agar diffusion method), antioxidant (method of ABTS/TEAC radicals) and anti-inflammatory (method of hyaluronidase enzyme) properties were condusted. RESULTS: Indicated that the phytocosmetic was stable and had low indices of microorganisms, according to Resolution 481/99. The bioactivity of the glycinin peptides was not altered or harmed by the other components of the emulsion. For the antimicrobial activity, the bacteria E. coli, S. aureus and P. acnes had values of 30.5 mm, 28 mm and 25 mm halos, respectively. For the antioxidant activity, the result was of 25.1 TEAC and the anti-inflammatory activity was measured at 83.4% inhibition of hyaluronidase enzyme. CONCLUSION: The study showed that the formulated phytocosmetic has great potential for topical use, it is comparable to other anti-aging cosmetics for daily skin care with antioxidant, anti-inflammatory and antimicrobial properties. INTRODUCTION: Phytocosmetic are gaining increasing attention from consumers who search for alternatives for the maintenance and protection of the skin. This article reports formulation of a phytocosmetic derived from defatted soybean flour, an emulsion base that is hydrolyzed from the glycinin protein (1000 µg/ g). MATERIAL AND METHODS: Test for stability, microbiological control and biological activities,antimicrobial (agar diffusion method), antioxidant (method of ABTS/TEAC radicals) and anti-inflammatory (method of hyaluronidase enzyme) properties were condusted. RESULTS: Indicated that the phytocosmetic was stable and had low indices of microorganisms, according to Resolution 481/99. The bioactivity of the glycinin peptides was not altered or harmed by the other components of the emulsion. For the antimicrobial activity, the bacteria E. coli, S. aureus and P. acnes had values of 30.5 mm, 28 mm and 25 mm halos, respectively. For the antioxidant activity, the result was of 25.1 TEAC and the anti-inflammatory activity was measured at 83.4% inhibition of hyaluronidase enzyme. CONCLUSION: The study showed that the formulated phytocosmetic has great potential for topical use, it is comparable to other anti-aging cosmetics for daily skin care with antioxidant, anti-inflammatory and antimicrobial properties.
Cleansing the hair is the cornerstone of any healthy hair regimen. A typical cleansing routine consists of shampooing the hair, followed by the application of a conditioner or, less frequently, a deep conditioner. Other important elements include the use of protein-containing conditioners and oils which can further enhance the benefits of routine cleansing. This chapter will provide an in-depth discussion of the role each of these product types plays in maintaining and promoting healthy hair.
Synopsis Substantivity of various ¹²⁵ I‐labelled collagen hydrolysates to virgin or bleached and dyed European hair or human callus was tested under conditions which simulated actual application of such hydrolysates in shampoos or foam baths. Factors which most strongly influence protein substantivity were identified. The molecular properties of the hydrolysate are the most important factor. The hydrolysate which adsorbed best had the lowest overall isoelectric point, the highest pH in solution and the largest content of high molecular weight peptides. The extent of adsorption was also a function of concentration of protein, of the duration of application and of the nature of the components of the formulation. Thus, the combination of shampoo and hydrolysate can be adjusted so that a desired substantivity is attained.
1. The binding of sodium dodecyl sulphate to proteins by equilibrium dialysis was investigated. 2. Most of the proteins studied bound 90-100% of their weight of sodium dodecyl sulphate. 3. The glycoproteins studied bound 70-100% of their weight of sodium dodecyl sulphate, calculated in terms of the polypeptide moiety of the molecule. 4. Proteins not containing S.S groups bound about 140% of their weight of sodium dodecyl sulphate. 5. Reduction of four proteins containing S.S groups caused a rise in sodium dodecyl sulphate binding to 140% of the weight of protein. 6. The apparent micellar molecular weights of the protein-sodium dodecyl sulphate complexes were measured by the dye-solubilization method; they were all found to have approximately the same micellar molecular weight (34000-41000) irrespective of the molecular weight of the protein to which they were attached.
A case of contact urticaria associated with a serous rhinitis, dyspnea, wheezing, and a dry cough appearing after the application of a hair conditioner on the scalp is reported. Prick test results with the conditioner diluted at 1/16 and 1/8 were strongly positive (+3), as well as a prick test (+3) with one component of the conditioner called "hydrolyzed proteins," which contained hydrolyzed bovine collagen and stearyl trimethylammonium chloride.
Protein hydrolysates (PHs) are added to hair-care products (to “repair” broken hair), soaps, bath gels, creams, etc. From one to 22 PHs used in hair-care products (collagen, keratin, elastin, milk, wheat, almond, and silk) were tested in three patient groups: A) 11 hairdressers with hand dermatitis B) 2160 consecutive adults with suspected allergic respiratory disease subjected to routine skin prick tests C) 28 adults with atopic dermatitis. In group A, all the 22 PHs were tested with scratch and patch tests. In groups B and C, one to three PHs were tested with prick tests. Positive scratch/prick test reactions were seen in 12 patients from three PHs altogether. All were women with atopic dermatitis, and all reacted to at least hydroxypropyl trimonium hydroly:ed collagen (Crotein Q”). In three patients, prick and open tests with a hair conditioner containing Crotein Q were performed with positive results. One patient reported contact urticaria on her hands, and two reported acute urticaria on their head, face, and upper body from a hair conditioner containing Crotein Q. In seven of the eight studied sera, specific IgE to Crotein Q was detected. In conclusion, PHs of hair cosmetics can cause contact urticaria, especially in patients with atopic dermatitis.
Amino acid composition analysis is a classical protein analysis method, which finds a wide application in medical and food science research and is indispensable for protein quantification. It is a complex technique, comprising two steps, hydrolysis of the substrate and chromatographic separation and detection of the residues. A properly performed hydrolysis is a prerequisite of a successful analysis. The most significant developments of the technology in the last decade consist in the (i) reduction of the hydrolysis time by the use of microwave radiation energy; (ii) improvement in the sensitivity of the residue detection, the quantification of the sensitive residues and separation of the enantiomeric forms of the amino acids; (iii) application of amino acid analysis in the large-scale protein identification by database search; and (iv) gradual replacement of the original ion exchange residue separation by reversed-phase high-performance liquid chromatography. Amino acid analysis is currently facing an enormous competition in the determination of the identity of proteins and amino acid homologs by the essentially faster mass spectrometry techniques. The amino acid analysis technology needs further simplification and automation of the hydrolysis, chromatography and detection steps to withstand the pressure exerted by the other technologies.
Immediate contact allergy to cosmetics seems to be rare, since only a few case reports on it have been published. We report on a case of IgE-mediated allergic contact urticaria caused by hydrolyzed wheat in a body cream.
Minimizing the cutaneous effects of anionic detergents; Cosmetics&Toiłetńes , 111 Imptombato; The bindin; of Sodium Dodecyl Sulphate to various proteins
  • A Teglia
  • G Secchi
A. Teglia, G. Secchi; Minimizing the cutaneous effects of anionic detergents; Cosmetics&Toiłetńes, 111, 8, p.61, 1996 (20) R. Pitt-Rivers, F.S.A. Imptombato; The bindin; of Sodium Dodecyl Sulphate to various proteins; Biochemical Journal, 109, p.825, 1968
Proteins: classic additives and actives for skin and hair care; Cosmetics&Toiletries, 113, 11
  • U Griesbach
  • M Klingels
  • V Homer
(9) U. Griesbach, M. Klingels, V. Homer; Proteins: classic additives and actives for skin and hair care; Cosmetics&Toiletries, 113, 11, p.69, 1998