Aloe barbadensis : A Plant of Nutricosmetic Interest

Abstract

Aloe barbadensis Miller (Aloe Vera Linne) products have long been employed in health foods and for medical purposes. It has anti-inflammatory, antifungal, antioxidant properties, which indicates excellent potential in antiaging cosmetic and skin protection products. The objective of this study is to evaluate the antiaging efficacy of dermocosmetic formulations containing A. barbadensis extract on young and mature skin using biophysical and skin imaging techniques. Twenty healthy adult volunteers participated in the study, aged between 20 and 65. The cream formulation, with 10% (w/w) of A. barbadensis extract, and placebo, were applied to the face of the volunteers. The effects were evaluated in terms of skin hydration and barrier effect by the measurement of transepidermal water loss (TEWL), derma firmness, and elasticity. The formulation containing A. barbadensis extract significantly improves water contained in the stratum corneum, firmness, elasticity of the skin, and decreased TEWL.

Full text

1Department of Pharmacy, University of Naples Federico II, Napoli, Italy
Corresponding Author:
Dini I, Dept. of Pharmacy, University of Naples Federico II, Via Domenico
Montesano 49, Napoli 80131, Italy.
Email: irdini@ unina. it
Original Article
Natural Product Communications
Volume 15(7): 1–6
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Aloe barbadensis: A Plant of
NutricosmeticInterest
Laneri S1, Di Lorenzo RM1, Bernardi A1, Sacchi A1, and Dini I1
Abstract
Aloe barbadensis Miller (Aloe Vera Linne) products have long been employed in health foods and for medical purposes. It has anti-
inflammatory, antifungal, antioxidant properties, which indicates excellent potential in antiaging cosmetic and skin protection
products. The objective of this study is to evaluate the antiaging efficacy of dermocosmetic formulations containing A. barbadensis
extract on young and mature skin using biophysical and skin imaging techniques. Twenty healthy adult volunteers participated in
the study, aged between 20 and 65. The cream formulation, with 10% (w/w) of A. barbadensis extract, and placebo, were applied to
the face of the volunteers. The effects were evaluated in terms of skin hydration and barrier effect by the measurement of transepi-
dermal water loss (TEWL), derma firmness, and elasticity. The formulation containing A. barbadensis extract significantly improves
water contained in the stratum corneum, firmness, elasticity of the skin, and decreased TEWL.
Keywords
Aloe barbadensis, TEWL, corneometry, cutometer, nutricosmetic, skin hydration
Received: March 27th, 2020; Accepted: May 11th, 2020.
The demand to prevent skin changes due to the aging process
has led to developing innovative cosmetic products. The scaly
and flaky appearance or the xerosis of the skin, occur in the
absence or deficiency of water. Moisturization is a crucial point
to maintain the skin soft, flexible, smooth, wrinkle- free, and
therefore preserve a youthful and beautiful appearance.
Hydration is critical for the typical operation of the skin and its
cells. Water levels mainly depend on the nature of the stratum
corneum (SC), the outermost epidermal layer of the skin, the
aging, and the destructive agents like the heat and the wind.
The demand of consumers in new natural ingredients and sci-
entific evidence for their efficacy has grown in the last years.
Aloe barbadensis contains carbohydrate polymers (glucoman-
nans), mucilage, fructose, acids (uronic acid, tannic acid), vita-
mins (A, C, E, D, B1, B2, B3), amino acids, and triterpenoids
(lupeol, campesterol, cholesterol, β-sitosterol) that exert pro-
tective or disease- preventing effects.1 Traditionally Aloe was
used to treating skin injuries due to burning and swellings.1
Although many studies have been carried out, clinical evidence
remains unclear. Therefore, further research needs to be done
to verify the effectiveness of A. barbadensis in cosmetic and
pharmaceutical preparations. The objective of this work is to
study, under real conditions of use, the efficacy of a cream
containing 10% A. barbadensis leaf extract as antiaging using
advanced biophysical techniques to determine hydration of the
epidermis and skin elasticity (Figure1).
The epidermis has 2 different levels of water, separated by the
interface between the stratum granulosum (SG) and the stratum
corneum (SC). Water present in the deeper epidermal layers goes
upward to hydrate cells in the SC, and in part, it is lost by evapo-
ration. Hydration of the upper skin layers decreases when the SC
water is lost less quickly than that arrived from the lower layers of
the skin.2 Therefore, to evaluate, it is necessary to check the tran-
sepidermal water loss (TEWL) and the water content in the SC.
The Tewameter can measure the TEWL, and the Corneometer
can evaluate the water content in the SC. Since water and lipid
contents determine the viscous resistance against deformation,
the viscoelastic properties of the skin were verified with a
Cutometer.3 This work is part of a project whose goals are the
research of natural products both of animal4 and vegetable origin
that can be used both topically and orally to inspire the formula-
tion of innovative products for beauty care with proven effective-
ness. The combination of topical agents and dietary supplements
results in a superior cosmetic benefit, as the problem is attacked
from opposing sides. The nutricosmetics “beauty from within”
market has expanded in recent years and will continue to grow in

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2
the coming years. It is considered the next frontier for improving
skin health and beauty. According to a report published by Global
Industry Analysts (2017), the nutricosmetics market size will
reach US$7.9 billion in 2025.5 Plant- based beauty is getting a sig-
nificant investment in the marketplace. Aloe barbadensis was used
in dermocosmetic cream considering its use in traditional medi-
cine (emollient and anti- inflammatory)6,7, in food preparation
(beverages, yogurts, desserts), functional food with antioxidant
and immune- modulatory preventive effects,8 and cosmetic prod-
ucts (suntan lotions, soaps, hand creams, cleansers, shampoos,
and hair tonics, shaving preparations, makeup, and baby lotion).9
Future studies should investigate treatment with A. barbadensis
supplement to verify the possible synergic effect of supplement
and cream to prevent skin aging.
Results and Discussion
The skin protects the body against water loss and stops micro-
organisms and viruses. Lipids and corneocytes of the SC make
a physical barrier; instead, lipids and sweat from the sebaceous
gland form a biochemical barrier. The maintenance of skin
barrier functionality depends on the SC hydration, the TEWL,
and the sebum level.10 If chemical or physical agents damage
the skin, the barrier function is compromised and an increase
of TEWL is detected. In this work, the Tewameter was used to
measure the water vapor that was released from the skin. It is a
non- invasive method for determining the efficiency of the bar-
rier function of the skin. The time course of TEWL following
application of the A. barbadensis cream and placebo were shown
in Figure2.
The topical application of the A. barbadensis cream decreases
the TEWL progressively from −22% after 1 hour to −28.0%
after 15 days from the use of testing cream, showing a positive
effect of the A. barbadensis cream on the functionality of the skin
barrier. Measurement of the moisturizer efficacy was evaluated
with a Corneometer. The latter evaluates the barrier capacity of
SC, and its results are indicative of the normal desquamation and
maturation of the SC. It is a non- invasive method based on the
Figure 1. Aloe barbadensis.

S etal. 3
measurement of the capacitance of the skin, which varies with
the water content. The capacitance measurements of the skin
surface are transformed into arbitrary hydration units.11
Corneometry time course results were illustrated in Figure3.
The topical application of A. barbadensis enhanced hydra-
tion units from 28% after 1 hour to 31% after 15 days from
the use of the tested cream, showing the ameliorative effect of
the A. barbadensis cream on the hydration of the skin barrier.
Aloe extract contains glucomannan, acemannan, and amino
acids that justify the moisturizing effect.12 The firmness of the
skin was calculated by measuring total skin displacement R0 in
mm. Cutometer R0 time course results were illustrated in
Figure4.
The R0 value for Aloe cream, decreasing by 18.4%, demon-
strated the cream’s ability to restore skin firmness. The stan-
dard parameter of elasticity (R2) was also determined. This
parameter represents the ability to return to the original posi-
tion after a mechanical pressure. The skin elasticity increased
when the R2 value is closer to 1 (100 %). Cutometer R2 time
course results were illustrated in Figure5.
Figure 2. Transepidermal water loss measurements. T0: before treatment; T1H: 1 hour after treatment; T24H: 24 hours after treatment; T15
Days: 15 days after treatment. All the measures are statistically significant (P < 0.05).
Figure 3. Hydration index. T0: before treatment; T1H: 1 hour after treatment; T24H: 24 hours after treatment; T15 Days: 15 days after
treatment. All the measures are statistically significant (P < 0.05).

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4
In our study, the R2 value, enhanced after 15 days of treat-
ment from 0.78 to 0.87 (+13,6%), confirmed the A. barbadensis
cream ability to improve the skin elasticity. The acemannan and
the aloeride in the A. barbadensis plant supported this evi-
dence.13 The acemannan stimulates lymphocyte response to
alloantigen, activates the interleukins-1 and 6, interferon, and
tumor necrosis factor, enhances the phagocytosis, and improves
the monocytes and the macrophages. The aloeride is a polysac-
charide able to activate nuclear factor (NF-κB).14-16 Defects,
inflammatory processes, and cancer occurred in the skin when
NF-κB activity decreased.
Materials and Methods
Treatment
The test was conducted according to the principles of the
Helsinki Declaration (Ethical principles for medical research
Figure 4. Skin firmness. T0: before treatment; T15 Days: 15 days after treatment. All the measures are statistically significant (P < 0.05).
Figure 5. Skin elasticity. T0: Before treatment; T15 Days: 15 days after treatment. All the measures are statistically significant (P < 0.05).

S etal. 5
that involves human subjects, Helsinki, Finland, June 1964)
and subsequent revisions endorsed by the European
Community (fourth revision, called Somerset West, South
Africa, 1996; Saunders and Wainwright, 2003) and according
to the Colipa Guidelines for the evaluation of the efficiency
of cosmetic products (May 2008). The technical staff applies
in single- blind, about 2 mg/cm2 of A. barbadensis cream or
placebo in the area of the face right and left of the volun-
teers, previously cleansed, avoiding direct contact with the
eyes and gently massaging until completely absorbed. TEWL
and corneometry measurements were read before putting
the cream (T0), after 1 hour (T1), 24 hours (T2), and 15 days
(T3) after the beginning of treatment. Cutometer measures
were done before cream application (T0) and after 15 days
(T1).
Aloe barbadensis Cream and Placebo Compositions
Oil phase: cetyl alcohol (2.5%), Helianthus annuus seed oil
(7.5%), polyglyceryl-3 methylglucose distearate (5.0%), cetearyl
alcohol (2.5%), tocopheryl acetate (1.0%).
Water phase: water (q.b to 100), A. barbadensis leaf extract
(10%), sodium benzoate, potassium sorbate, phenoxyethanol
(0.5%), perfume (0.1%).
The placebo cream contains all the components without
Aloe leaf extract. All cream’s ingredients were purchased from
ACEF (Fiorenzuola D’Arda, Italy) and Parfum by Farotti
essenze (Rimini, Italy). Aloe extract (active water extract Aloe
leaf cosmos) was purchased from ACEF (Fiorenzuola D’Arda,
Italy).
Formulation development. The formulations used are O/W
emulsions containing ingredients listed before. The oil phase
was prepared placed on a heating plate so that a liquid oily com-
ponent was formed. At the same time, the water was heated
up to the same temperature as the oil phase. Subsequently, the
aqueous phase is poured flush into the oil phase, shaking vigor-
ously by a Silverson L5M- A Laboratory Mixer; after the emul-
sion was cooling in an ice bath and, at room temperature, the
remaining components were added. The pH of emulsions was
calculated with a PHmeter Crison GPL20 (Hach Lange Spain,
S.L.U.3, Barcelona, Spain), and its viscosity (28.640-30.314
mPa; L4, 20 rpm) was calculated with a rheometer Visco Basic
Plus, Fungilab (Barcelona, Spain).
Instrumental Measurements
Instrumental measurements were made after a 30- minutes
acclimatization period in a room maintained at 20‐24°C and
with relative humidity of 50% ± 5% as recommended by
guidelines from the European Group for Efficacy
Measurements on Cosmetics and Other Topical Products
(EEMCO).17
Transepidermal water loss. TEWL was measured utilizing a
Tewameter Probe Dual MPA 580 (Courage +Khazaka elec-
tronic GmbH, Köln, Germany).
Skin hydration. Skin hydration was measured using a Probe
Corneometer DUAL MPA 580 (Courage +Khazaka electronic
GmbH Mathias- Brüggen- Str.91 50829 Köln, Germany). Six
successive measurements were taken at 5‐second intervals, and
the mean value was calculated for each skin site. Results were
expressed in arbitrary units.
Skin firmness and elasticity. Skin firmness and elasticity
were evaluated using a Cutometer dual MPA 580 (Courage
+Khazaka Electronic, Köln, Germany). A constant pressure
with a probe (2 mm diameter) of 350 mbar for 5 seconds, fol-
lowed by a relaxation time of 1 second for 5 repetitions, was
applied.18 The curves of skin deformation were analyzed using
the Cutometer Dual Version 1.4.6.2 software. R0 (skin firm-
ness) and R2 (skin elasticity) parameters were evaluated.19
Volunteer Selection
Twelve Caucasians volunteers (healthy adults), aged between
20 and 65 years, were enrolled in the study. According to the
Helsinki declaration of ethical principles for medical research,
all volunteers signed an informed consent page and are subject
to a careful clinical examination and thorough case history.
Inclusion criteria. Participants were obligatory to renounce to
the use of dietary supplements, exposure to artificial ultraviolet
treatment, cosmetic products on the forearms. Also, only the
subjects who are cooperative, able to follow the instructions,
and comply with the study requirements were enrolled.
Exclusion criteria. People do not engage were women who
are pregnant or nursing during 3 months or more from the
study start; people with a history of intolerance reactions or
skin hyper- reactivity to product constituents, skin diseases, suf-
fering (eczema, psoriasis, lesions), receiving topical retinoids
during the previous 12 months and systemic retinoids in the
last 45 days before the start of the study.
Statistical Tests
The analysis of variance test was performed using IBM SPSS
software (version 15; Milan, Italy). For all experiments, the dif-
ferences were significant at a value of P ≤ 0.05.
Conclusion
This study showed that the A. barbadensis cream improves skin
barrier function, increases the skin’s moisture content, and
enhances skin firmness and elasticity more than a placebo
cream. According to the in vivo results, the topical application
of A. barbadensis cream promises results in preventing skin

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6
aging. Future studies should investigate treatment with A. bar-
badensis supplement to verify the possible synergy effect of
supplement and cream to prevent skin aging.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect
to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research,
authorship, and/or publication of this article.
References
1. Eshun K, He Q. Aloe vera: a valuable ingredient for the food,
pharmaceutical and cosmetic industries--a review. Crit Rev Food
Sci Nutr. 2004;44(2):91-96. doi: 10. 1080/ 1040 8690 4904 24694
2. Guzmán- Alonso M, Cortazár TM. Water content at di_erent skin
depths and the influence of moisturizing formulations. Househ
Pers Care Today. 2016;11:35-40.
3. Wissing SA, Mader K, Muller RH, nanopartices Slipid. Sln) as
a novel carrier system offering prolonged release of the per-
fume Allure (Chanel). in proC int Symp. Control Rel Bioact Mater.
2000;27:311-312.
4. Laneri S, Lorenzo RD, Sacchi A, Dini I. Dosage of Bioactive
Molecules in the Nutricosmeceutical Helix aspersa Muller Mucus
and Formulation of New Cosmetic Cream with Moisturizing
Effect. Nat Prod Commun. 2019;14(8):1-7. doi: 10. 1177/ 1934
578X 19868606
5. Nutricosmetics Market and Beauty Beverages. Drinks - Global
Industry Analysis, Size, Share, Growth, Trends and Forecast 2017
– 2025. https://www. reportlinker. com/ p05027986/ Nutricos-
metics- Market- and- Beauty- Beverages- Drinks- Global- Industry-
Analysis- Size- Share- Growth- Trends- and- Forecast. html
6. Grindlay D, Reynolds T. The Aloe vera phenomenon: a review
of the properties and modern uses of the leaf parenchyma gel.
JEthnopharmacol. 1986;16(2-3):117-151. doi: 10. 1016/ 0378- 8741(
86) 90085-1
7. Dini I, Laneri S. Nutricosmetics: a brief overview. Phytother Res.
2019;33(12):3054-3063. doi: 10. 1002/ ptr. 6494
8. Upadhyay RK. Nutraceutical, therapeutic and pharmaceu-
tical potential of Aloe vera: a review. Intern J Green Pharm.
2018;12(1):51-70.
9. Gallagher J, Gray M. IsAloe vera effective for healing chronic
wounds? JWound Ostomy Continence Nurs. 2003;30(2):68-71. doi:
10. 1067/ mjw. 2003. 16
10. Luebberding S, Krueger N, Kerscher M. Age- related changes in
skin barrier function - quantitative evaluation of 150 female sub-
jects. Int J Cosmet Sci. 2013;35(2):183-190. doi: 10. 1111/ ics. 12024
11. Barel AO, Clarys P. Invitro calibration of the capacitance method
(Corneometer cm 825) and conductance method (Skicon-200) for
the evaluation of the hydration state of the skin. Skin Res Technol.
1997;3(2):107-113. doi: 10. 1111/ j. 1600- 0846. 1997. tb00171.x
12. Sierra- García GD, Castro- Ríos R, González- Horta A, Lara-
Arias J, Chávez- Montes A. Acemannan, an extracted polysac-
charide from Aloe vera: a literature review. Nat Prod Commun.
2014;9(8):1217-1221. doi: 10. 1177/ 1934 578X 1400 900836
13. Verdier- Sévrain S, Bonté F. Skin hydration: a review on its molec-
ular mechanisms. J Cosmet Dermatol. 2007;6(2):75-82. doi: 10.
1111/ j. 1473- 2165. 2007. 00300.x
14. Binic I, Lazarevic V, Ljubenovic M, Mojsa J, Sokolovic D. Skin
ageing: natural weapons and strategies. Evid Based Complement
Alternat Med. 2013;2013(248):1-10. doi: 10. 1155/ 2013/ 827248
15. Mukherjee PK, Nema NK, Maity N, Mukherjee K, Harwansh RK.
Phytochemical and therapeutic profile of Aloe vera. JNat Rem.
2014;14(1):1-26.
16. Sur I, Ulvmar M, Toftgård R. The two- faced NF-κB in the skin.
Int Rev Immunol. 2008;27(4):205-223. doi: 10. 1080/ 0883 0180
8021 30319
17. Baltazar D, Marto J, Berger T, Pinto P, Ribeiro HM. The antiage-
ing efficacy of donkey milk in combination with pomegranate
extract and UV protection a traditional ingredient in a modern
formulation. Agro Food Ind Hi- Tech. 2017;28:25-27.
18. Berardesca E, Loden M, Serup J, Masson P, Rodrigues LM. The
revised EEMCO guidance for the in vivo measurement of water
in the skin. Skin Res Technol. 2018;24(3):351-358. doi: 10. 1111/ srt.
12599
19. Dobrev H. Application of Cutometer area parameters for the
study of human skin fatigue skin Res. Technol. 2005;11:120-122.