Cosmetics, Volume 6, Issue 2 (June 2019) – 15 articles

The fusion of ethnicity in human populations is becoming increasingly common, so the conventional definition of ethnicity is going to become deficient. The aim of this study was to investigate the hair properties which emerge from combinations of multiple races. Hair fibers collected from mixed-race subjects were investigated and classifications of hair shape as well as measurements of thickness, ellipticity and surface damage were carried out. The results show that hair shapes varied widely: straight hair and very curly hair often existed together on the heads of individuals with mixed ethnicity. Curly hair tended to be thicker than loose wavy hair. As for damage to the hair surface, the hairs of mixed-race subjects showed a very unique property in that they were much more severely damaged near the root (the proximal end) than the hairs of monoracial subjects. The hair shape (curly or loose wavy) was not related to the level of damage. The severe damage near the proximal end is thought to be caused by entanglement, due to the presence of various curl phases. This study reports the unique characteristics of hairs of subjects with mixed ethnicity, which have never been noted in the previous studies on subjects with a monoracial background. Full article

Alpha lipoic acid (ALA) is a well-known anti-aging compound. The activity of this molecule is limited by two important factors: (i) The low stability to oxidation and thermal processes and (ii) the low solubility. Particularly the latter limits ALA formulation in hydrophilic bases. The purpose of this paper is to present a new technological approach to stabilize lipoic acid in topical hydrogels for cosmetic use. With this aim, ALA was intercalated in two different lamellar anionic clays (hydrotalcites), MgAl and ZnAl, obtaining the hybrids MgAl-ALA and ZnAl-ALA. The intercalation allows to obtain a more manageable product in comparison to raw ALA. After the preliminary characterization, hydrogels containing the hybrids were prepared and characterized, also in comparison to the commercial product Tiobec^® in terms of rheological properties, stability to temperature and centrifugation, release, and cytotoxicity. The obtained results highlighted that the hydrogel containing MgAl-ALA is a suitable alternative to the products currently available on the market. Full article

Caesalpinia spinosa gum is a vegetal polysaccharide obtained by grinding the endosperm of Caesalpinia spinosa seeds. It is commonly used as a rheology modifier in food industry. Its rheological behavior, compatibility with common cosmetic ingredients, and application as a thickener in different types of cosmetic formulations were investigated in this article. At low concentrations (0.1–0.2%) the behavior is Newtonian; at higher percentages (0.5–2.0%) it is pseudoplastic without thixotropy. The gum was tested in combination with salts, chelating agents, humectants, thickeners, pigments, nano UV filters, surfactants, conditioners, and ethanol, as well as in acidic/alkaline conditions. The wide compatibility and the interesting sensory profile, even in association with other thickeners, make the Caesalpinia spinosa gum a very promising ingredient for the thickening of various cosmetic products. Full article

Recently, cannabis, or its major constituent cannabidiol (CBD), has emerged as an attractive cosmetic ingredient. Initiated as a basic investigation of the physiological roles of cannabinoid receptors and their endogenous ligands, endocannabinoids’ diverse potential benefits have been proposed for using cannabinoid receptor modulating compounds in skin health. Improvement in skin barrier functions, alleviating inflammatory responses, and the relief of itching sensations are some commonly expected therapeutic benefits, which have been supported by many in vitro, in vivo, and clinical studies. While hemp seed oils or hemp extracts might be used for the cosmetic formulation, the potential for contamination with a psychoactive cannabinoid, such as 9-THC, should be carefully checked. Instead of using hemp-derived ingredients, the use of cannabinomimetics, synthetic ligands on cannabinoid receptors, or entourage compounds (which modulate intracellular synthesis and the degradation of endocannabinoids), have been tried. In this review, a brief introduction of the epidermal endocannabinoid system (EES) and its physiological roles will be followed by a review of the cosmetic and dermatologic application of cannabinomimetics and entourage compounds. The practical application of newly developed endocannabinomimetics will be discussed as well. Full article

The cuticle is the outermost layer of overlapping flattened cells of hair and has been subjected to many years of study to understand its structure and how it develops in the follicle. The essential function of the cuticle with its tough inelastic protein content is to protect the inner cortex that provides the elastic properties of hair. Progress in our knowledge of hair came from studies with the electron microscope, initially transmission electron microscopy (TEM) for internal structure and later the scanning electron microscope (SEM) for cuticle surface shape and for investigating changes caused by various environmental influences such as cosmetic treatments and industrial processing of wool. Other physical techniques have been successfully applied in conjunction with proteomics. The outstanding internal features of the cuticle cells are the internal layers consisting of keratin filament proteins and the keratin-associated proteins. The stability and physical toughness of the cuticle cell is partly accounted for by the high content of disulphide crosslinking. The material between the cells that holds them tightly together, the cell membrane complex, consists of a layer of lipid on both sides of a central protein layer. The lipid contains 18-methyleicosanoic acid that is part of the hydrophobic lipid surface of hair. For the past decade there have been aspects that remained unanswered because they are difficult to study. Some of these are discussed in this brief review with suggestions for experimental approaches to shed more light. Full article

In this paper, surface degradation of hair is reviewed. Surface properties such as hydrophobicity and surface friction change as surface structures of hair fiber, that is, 18-methyleicosanoic acid (18-MEA) and epicuticle, degrade. Comparison of contact angle and amount of 18-MEA from root to tip of the sampled hair fibers clarified the contribution of not only 18-MEA but also epicuticle to surface properties. It was found that chemical treatment by itself, such as bleaching, is not enough to cause complete loss of hydrophobic nature even after 18-MEA is removed. Additional weathering processes, such as repeatedly shampooing, are required. A technology for the deposition of a persistent hydrophobicity to bleached and weathered hair surfaces using 18-MEA is presented. Combination of 18-MEA with specific cationic surfactants (Stearoxypropyldimethylamine: SPDA) made the bleached and weathered hair surface hydrophobic, and its hydrophobicity was maintained even after shampooing. Characterization of adsorbed layers of 18-MEA/SPDA on a mica surface, as a possible hydrophilic surface model, was performed using atomic force microscopy (AFM) and angle-resolved X-ray photoelectron spectroscopy (AR-XPS). The effects of the anteiso-branch moiety of 18-MEA to create a persistent hydrophobicity with 18-MEA/SPDA were investigated using controlled AFM. It was revealed that the anteiso-branch moiety of 18-MEA in the 18-MEA/SPDA system produces a persistent hydrophobicity by providing higher fluidity to the upper region of the 18-MEA/SPDA layer. The contribution to hair beauty and sensory feeling as one of the practical functions of the hair surface is described in this paper. The hydrophobic nature of the hair surface reduces surface friction in a wet state, which reduces hair disorder alignment. It is also revealed that the moisturized or dried out feeling strongly depends on the hair shape (meandering and diameter) which depends on hair surface properties in a wet environment. Full article

Olive trees (Olea europaea) and their processed products, such as olive oil, play a major role in the Mediterranean way of life. Their positive impact on human health is being intensely investigated. One research topic is the identification of new application areas of olive mill wastewater (OMWW). OMWW is characterized by the high content of polyphenols possessing many positive health effects. Thus, the phenol-enriched OMWW extract offers the potential for the treatment of skin disorders and for cosmetic application. The aim of the present study was to evaluate cell viability and proliferation, the anti-inflammatory and anti-oxidative properties of a phenol-enriched OMWW extract on an immortal keratinocyte cell line (HaCaT cells). Moreover, the influence on the growth of various microorganisms was investigated; furthermore, the effects on normal human epidermal keratinocytes (NHEK) and human melanoma cells (A375) were studied in a commercially available tumor invasion skin model. The phenol-enriched OMWW extract showed excellent antimicrobial activity. Moreover, a noticeable reduction in reactive oxygen species formation as well as Interleukin-8 release in HaCaT cells were observed. Finally, the inhibited growth of A375 melanoma nodules in the melanoma skin model could be shown. Our results indicate that the OMWW extract is a promising ingredient for dermal applications to improve skin health and skin protection as well as having a positive impact on skin ageing. Full article

Personalized or customized cosmetics are increasing in popularity. While compliance with the EU Cosmetics Regulation 1223/2009 is mandatory, there are no clear guidelines to ensure their compliance. While cosmetic products are subject to numerous regulations, permitting their sale within the European Single Market, this article focusses on the requirements of the Cosmetics Regulation 1223/2009. Certain provisions of the Regulation are considered and possible solutions proposed to enable the safe use of personalized cosmetics placed on the market. Full article

Although toothpastes are considered as topical cosmetics that are not normally ingested, it is evident that they may contribute to the introduction of heavy metals and xenobiotics through buccal and gastrointestinal absorption. The purpose of this study was to determine the potential presence of metals and polyphenols in conventional, children’s and herbal toothpastes. Metal analysis was conducted by using the Microwave Plasma-Atomic Emission Spectrometer and the total polyphenolic content was determined by using the Folin–Ciocalteu test. Results showed that cadmium and mercury were absent in all toothpastes while zinc and tin exhibited high values. This was because the latter two metals are incorporated as part of the ingredients. In the case of polyphenols, the highest value was obtained in one of the samples from the children’s toothpaste category while the lowest value was obtained from the conventional toothpaste category. Lead and nickel were two other metals that fell outside the limits for EU and US standards. Most of these limits are usually applicable to topical cosmetic products or food products. However, these may not adequately cover oral hygiene products, such as toothpastes. Full article

Phytomelatonin (PM) gained the greatest interest for its application in agriculture and its use to improve human health conditions. PM based supplement has been shown to possess antioxidant capabilities because it functions as a free radical scavenger. Reactive Oxygen Species (ROS), induced by both intrinsic (peroxide production) and extrinsic (UV-radiation) factors are biochemical mediators crucial in skin aging. Skin aging is also regulated by specific microRNAs (miRs). Herein we have shown the effect of PM free radical scavengers on the human keratinocyte cell line HaCat and on ROS formation induced by both extrinsic and intrinsic factors as well as their capability to positively modulate a member of the hsa-miR-29 family linked to aging. Our result highlights the regulatory role of PM for the keratinocytes homeostasis. Full article

Consumer awareness about the damages that plastic packaging waste cause to the environment, coupled with bio-economy and circular economy policies, are pushing plastic packaging versus the use of bio-based and biodegradable materials. In this contest, even cosmetic packaging is looking for sustainable solutions, and research is focusing on modifying bio-based and biodegradable polymers to meet the challenging requirements for cosmetic preservation, while maintaining sustainability and biodegradability. Several bio-based and biodegradable polymers such as poly(lactic acid), polyhydroxyalkanoates, polysaccharides, etc., are available, and some first solutions for both rigid and flexible packaging are already present on the market, while many others are under study and optimization. A fruitful cooperation among researchers and industries will drive the cosmetic sector toward being more ecological and contributing to save our environment. Full article

Some vegetable oils have many biological properties, including UV-absorbing capacity. Therefore, their use has been suggested to reduce the content of organic UV-filters in sunscreen products. In this work, we investigated the feasibility of developing oil-based vehicles with a high sun protection factor (SPF) using pomegranate oil (PMG) and shea oil (BPO) in association with different percentages of organic UV-filters (octyl– methoxycinnamate, butyl methoxydibenzoylmethane, and bemotrizinol). We characterized the spreadability, occlusion factor, pH, and required hydrophilic lipophilic balance of the resulting formulations, and did not observe relevant differences due to the incorporation of vegetable oils. The in vitro spectrophotometric determinations of SPF values highlighted that the addition of BPO (1% (w/w)) and PMG (1% (w/w)) resulted in an increase in SPF in comparison with the same formulations that contained only organic UV-filters. The SPF increase was more significant for the formulations that contained lower amounts of organic UV-filters. The results of this study supported the hypothesis that including suitable vegetable oils in sunscreen formulations could be a promising strategy to design products with a lower content of organic UV-filters. Full article

(1) Background: The objective of this work was to elucidate the hair microstructure which correlates with the stiffness of human hair fibers. (2) Methods: Bending moduli of hair fibers were evaluated for the hair samples from 156 Japanese female subjects. Hair transverse sections were dual-stained with fluorescent dyes which can stain para- and ortho-like cortical cells separately, and observed under a fluorescence light microscope. Atomic force microscopy nanoindentation measurements were performed to examine the modulus inside macrofibrils. (3) Results: The difference in bending moduli between the maximum and the minimum values was more than double. The hair of high bending modulus was rich in para-like cortical cells and the bending modulus significantly correlated with the fraction of para-like cortical cells to the whole cortex. On the other hand, the elastic moduli inside macrofibrils were almost same for the para- and ortho-like cortical cells. (4) Conclusions: Hair bending modulus depends on the fractions of the constitutional cortical cell types. The contribution of the intermacrofibrillar materials, which differed in their morphologies and amounts of para- and ortho-like cortical cells, is plausible as a cause of the difference in the modulus of the cortical cell types. Full article

Inspired by the iron gall ink that has been used since the Middle Ages, we formulated a hair-dyeing solution for blackening hair. The ingredients in the formulation have been approved as cosmetic ingredients, including tannic acid, gallic acid, and Fe(d-gluconate)₂. The formulation does not require any harmful oxidizing agents, such as hydrogen peroxide—the Fe(II) cations bound to tannins are oxidized spontaneously upon exposure to air and form the blackish Fe(III)-tannin nanocomplex that coats hair firmly. In our study, we show that the dyed color did not fade under sunlight exposure for at least three months and after shampooing. This natural formulation for black hair-dyeing can have great impact in the hair cosmetic industry. Full article

(1) Background: Fragrance sensitization is common in Italy and their constituents are used in many cosmetics and detergents. The objective of the study was to analyze the temporal trend of sensitivity to fragrance mix-1 in northeastern Italy and to evaluate gender differences; (2) Methods: From 1996 to 2016, 27,381 consecutive patients with suspected allergic contact dermatitis were patch tested. Individual characteristics were collected through a standardized questionnaire in six departments of dermatology or occupational medicine; (3) Results: The overall prevalence of sensitization to fragrance mix-1 was 7.3%; the prevalence was significantly higher in women (7.7%) than in men (6.3%). From 1996 to 2016, we observed an increase of this sensitization, ranging from 6.2% to 7.7% in males and from 7.2% to 9.1% in females; (4) Conclusions: Our study showed that contact allergy to fragrance mix-1 is important in both sexes and prevalence is increasing over time, despite the introduction of new fragrances with lower sensitization potential. There is the need to reduce the use of fragrances mix-1 to stop the increase of sensitization in exposed subjects. Full article