The term natural oil refers to a fixed (non-volatile) oil of animal or plant origin. These types of oils – in contrast to essential (volatile) oils, which are obtained by steam distillation methods of plant matter – are typically obtained from plant seeds and nuts by a mechanical pressing technique or solvent extraction. The natural movement in cosmetics of the 21st century has led to renewed interest in formulating skin care products with botanical ingredients. In this article, we discuss the benefits and caveats of natural oil treatments as moisturizing agents (as occlusives and emollients) as well as their utility in wound healing and treatment of skin diseases. We also address the paradoxical behaviour of natural oils in relation to barrier function and highlight the current state of our knowledge with respect to the use of natural oils in neonatal skin care. Finally, we provide a comparison of natural oils to conventional petroleum-based oils.
Development of in vivo confocal Raman spectroscopy (ICRS) methodology over the last 20 years has enabled previously unavailable capability to acquire molecular concentration gradients across the stratum corneum (SC), at the micron level and in a clinical setting. Professor Tony Rawlings has been a driving force in SC research for over 30 years, working with a wide range of teams across the world. Because a detailed knowledge of skin biochemistry was key to interpreting ICRS-acquired molecular concentration gradients, the authors formed a close working relationship with Professor Rawlings during the development of ICRS. This article, therefore, presents a summary of this process and how challenges raised by application of ICRS were tackled, towards the goal of validating the technique for clinical skin measurement.
Ex vivo skin has been used to study various skin conditions from atopic dermatitis to burn injury. The aim of this research is to identify a more effective barrier improvement strategy and to evaluate topical formulations in replenishing the skin. The skin can create new longer chain fatty acids and ceramides (CERs) from topically applied skin natural fatty acid to help renew the skin's barrier.
An ex vivo skin model damaged by sequential tape stripping of the stratum corneum (SC) was used to investigate the repair of the SC. Confocal laser scanning microscopy was used to assess the SC layers recovered. Ultrastructural analysis was performed using transmission electron microscopy to visualize the lamellar bodies and intercellular lipid lamellae.
The data in this study provide the first direct ex vivo evidence comparing different marketed formulations containing three CERs with those containing fatty acids. Free fatty acid (FFA)-containing formulations, but not CER-containing formulations, directly applied to the damaged skin, showed an increased number of repaired SC layers and this was reflected at the ultrastructural level by an increased intercellular lipid lamellae length and an increased number of lamellar bodies.
These findings demonstrate that FFA-containing formulations can repair damaged ex vivo skin and point to a repair mechanism in which topically applied palmitic and stearic acids, (which boost lipid levels and elongation) can increase the production and transport of lipids into a repaired SC and thus rebuild an effective skin barrier.
Anthony V. Rawlings has had 30+ years of experience in the general area of skin science. He has many scientific publications, and his work has been highly cited. He has made major contributions to our understanding of skin physiology, including xerosis and hydration, barrier function, desquamation, the corneocyte envelope, physical chemistry of stratum corneum lipids, photodamage and ethnic variation. He has held management positions with several companies in the US and UK, established AVR Consulting in 2002 and maintained a long-standing relationship with colleagues at University College London. His time as the Editor in Chief of the International Journal of Cosmetic Science was pivotal in the development of the journal. He worked hard and succeeded in getting the IJCS included in the PubMed database.
While there are a wide range of approaches for the assessment of skin hydration, it is not always clear how data from them relate to one another or to the skin itself. With the development of in vivo Confocal Raman Spectroscopy (ICRS), it has become possible to measure water concentration as a function of protein/depth within the stratum corneum (SC). This article reports a comparison between electrical skin hydration measures/visual/optical grading and water concentration profiles measured using ICRS, to better understand the relationship between these approaches.
SC hydration of lower-leg skin with varying degrees of dryness was assessed using visual grading (live and from digital images), Corneometer®, Visioscan and ICRS. In addition, a custom fingerprint sensor was used to image surface capacitance (as a surrogate of SC hydration), and SC barrier function was assessed using evaporimetry (to measure trans-epidermal water loss; TEWL).
Significant correlations were observed between a number of different skin grading/measurement approaches and ICRS data. ICRS hydration profiles also revealed a region near the SC surface with a relatively flat water profile in dry skin subjects.
The advent of quantitative in vivo analytical techniques such as ICRS, which can be used in a clinical setting, has enabled greater insight into more conventional approaches for assessing skin dryness. While traditional skin grading and biophysical methods for measuring skin hydration have varying degrees of correlation with one another, they also provide comparatively unique information about different regions within the SC. This should enable a more informed approach to product development in the future.
This paper aims to develop and validate a taxonomy for the assessment of the subjective experience of curly hair manageability. It represents the latter of two iterative stages of a mixed-method design interdisciplinary project.
The qualitative stage of the study incorporated thematic analysis of 14 interview transcripts generated using a video-ethnographic method (SEBE). A survey-based instrument assessing different elements of the construct of hair manageability designed during the first stage of this project was further developed following consultations with experts with extensive experience in hair research, product development, testing and trichology. The instrument was tested online with 506 female participants self-reporting natural curly hair, types 3A and higher according to the Andre Walker Curl Classification.
The initial construct of four groups of hair goals received positive content validity from the experts. High scale reliability was achieved for the aesthetic, haptic and emotive goals' scales as well as for hair esteem (Cronbach's alpha >0.75). Curl type was the only personal hair attribute that was correlated with hair goals and perceptions. From the demographic and lifestyle data, only age was correlated with goals and willingness to try new products. Common hair practices and product usage were also correlated with hair curl and goals.
The appropriateness of the instrument for measuring the strength of different hair goals and perceptions relevant to hair curvature degree and hair esteem has been validated. The instrument will support the development and testing of products better aligned with the manageability needs of very curly and textured hair. It was also confirmed that hair curvature is the most significant determinant of practices, and age of product attitudes.
This study focused on the development of a new-to-world ingredient harnessing the natural potential of fresh Jasminum grandiflorum flowers to self-ferment by its phytobiome revealing flower content. Analytical investigations were conducted to highlight specific phytocompounds generated during the natural fermentation of flowers in comparison to a conventional extraction. The synergy with another extraction technology maximized the generation of biocompounds for an interesting efficacy.
Jasmine extract was elaborated by combining two patented technologies: the phytofermentology™, inspired by plant–microorganisms interaction and designed to develop ingredients obtained by natural fermentation of the vegetal using its own phytobiota; and the PSR™ technology allowing the extraction of bioactive phytocompounds such as small RNAs from plants.
Analytical investigations of Jasmine extract highlighted uniqueness and richness of the phytocompound profiles, such as organics acids and phenolic compounds, markers of fermentation only obtained after phytofermentology in comparison to conventional extraction. Jasmine extract has the particularity to contain jasmintides, flower small peptides belonging to the family of cysteine-rich peptides (CRPs). Antioxidant and global anti-ageing properties were investigated in cell-free assays demonstrating interesting results: about 20% scavenging of free radicals from 0.5% of Jasmine extract and protection from DNA damage of 26% in comparison to a stressed control.
Phytofermentology™ technology combined with PSR™ technology, meant to be respectful of the environment, allowed to development of biofunctionals very close to nature with a unique analytical signature as Jasmine extract, using the potential of fresh flowers phytobiota to self-ferment. The efficacy of the ingredient on global antioxidation and anti-ageing via hyaluronidase/tyrosinase inhibitions was highlighted by cell-free evaluation assays. Further and complementary studies should be conducted to confirm the bioefficacy of this ingredient with in vitro / ex vivo assays.
Exploring the effects of age on microbial community structure and understanding the effects of chronological ageing as well as sun exposure on microbial community diversity.
The microbial characteristics of the facial skin of 98 adult women aged 18–70 years were studied using 16S rRNA gene sequencing, and differences based on age and reported sun exposure were assessed.
The cheek skin's bacterial diversity and richness increased with age. The relative abundance of Cutibacterium decreased with age, while the relative abundance of Corynebacterium, Anaerococcus, Paracoccus, Micrococcus, Kocuria, Kytococcus, and Chryseobacterium increased. In addition, an increase in Micrococcus and a decrease in Cutibacterium were observed in volunteers with more than 2 h of daily sun exposure compared to volunteers with <2 h of daily sun exposure. Under low-sunlight conditions, Cutibacterium was more prevalent in the youth group, and Corynebacterium, Anaerococcus, and Kytococcus were more prevalent in the older group.
The diversity and composition of the bacterial community on the cheeks are affected by age and extrinsic factors (sun exposure) may also play a role in this.
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