A New, Rapid Method for Examining Potential Skin-Brightening Ingredients Using Apple Slices.

Darkening of fruits is the result of the oxidative activation of polyphenol oxidase converting low-molecular weight phenols present in the fruit body into quinone intermediates. Then, through polymerization, these reactive quinones convert to light yellow and red low-molecular weight melanin and, given enough time, to darker, higher molecular weight brown and black melanin. The process that occurs in the flesh of cut fruit is very similar to the process that human skin cells use to make melanin: the oxidative activation of tyrosinase and conversion of tyrosine to dopaquinone and eventually to darker melanin. The conversion of the phenols by tyrosinase to quinones is the rate-limiting step in the biochemical manufacture of melanin. This article will discuss a new and cost effective way to screen skin-brightening ingredients by the use of apple slices as a model for skin using a chromameter to measure the change in color that occurs in apple slices over a short time course. Such measurements have been popularly used by food manufacturers to examine ingredients that inhibit fruit browning. Interestingly, as will be noted, many of the ingredients used commercially to inhibit food browning are also popular skin-brightening ingredients. We have found that a DermaLab (Cortex Technologies, Hadsund, Denmark) chromameter measuring the erythema index of apple slice darkening appears to be able to differentiate the benefit of a formulation containing azelaic acid, a known skin-lightening ingredient, to minimize the darkening effects that occur in sliced apples. We will discuss how different apples behave differently when cut and how to best use the chromameter to analyze the changes that occur that can potentially help rapidly screen ingredients for their skin-brightening benefits.

Structure/property comparisons of chemistries based on renewable 1,3-propanediol and petroleum-derived alkylene oxides.

Structure/property comparisons were made of chemistries based on renewable 1,3-propanediol (PDO)- versus petroleum-based alkylene oxides as well as comparisons of the respective polyethers, emulsifiers, and cosmetic formulations based on these feedstocks. Green Chemistry Principles were applied in the manufacture of polyethylene glycol (PEG)-free renewable PDO-based oligomers and PDO-based fatty acid ester emulsifiers. Sustainable cosmetic products formulated with renewable PDO-based emulsifiers gave equivalent performance in sensory and moisturization evaluations compared to those formulated with the petroleum-derived PEG-based emulsifiers.

Examining Skin Recovery After a 3% Aqueous Hydrogen Peroxide (H2O2) Treatment Using ATP Biofluorescence.

Introduction: Since its complete mapping, the human skin microbiome has become an important area of research related to skin health. The human skin is populated by an environment of microorganisms, fungi, insects, and viruses that is collectively known as the microbiota, and the complete genomic contribution to the skin is called the microbiome. The terms are different but frequently used interchangeably. Measuring the skin's microbial diversity can be done, but it is a sophisticated technique that is performed using expensive instruments that can sequence the 16S ribosomal RNA of the microorganisms. Finding more rapid and less costly methods to analyze the changes in the skin's microbial biome is desirable. Methods: A study was conducted on thirty (30) inner volar forearms to see if ATP biofluorescence could be employed to examine skin microbial dysbiosis caused by the application of 3% hydrogen peroxide. Fifteen individuals were examined on both arms for a total of thirty inner volar forearms using a Charm Science® NovaLum® ATP analyzer to examine in a broad sense the skin's total microbial population and how it is affected after surface treatment with 3% hydrogen peroxide over a 24-hour period. Results: It was found that surface treatment of the skin with three cotton swab applications of 3% hydrogen peroxide five minutes apart was able to statistically significantly suppress the expression of ATP biofluorescence compared against un-swabbed sites and the effects remained significant for six hours following the H2O2 treatment. After 8 hours, and into the 24th hour, the ATP biofluorescence difference returns to non-statistical significance indicating potential return of the stable microbiota. Discussion: Using ATP biofluorescence to detect possible sanitizer-induced microbial dysbiosis may be a rapid way to examine how skin treatments may impact the return of microbially disrupted skin to its normal state and how surface treatments may impact the rate of return to normal after a disruptive event.

Hyaluronic acid (HA) stimulates the in vitro expression of CD44 proteins but not HAS1 proteins in normal human epidermal keratinocytes (NHEKs) and is HA molecular weight dependent.

BACKGROUND: In the skin, hyaluronic acid is broken down to smaller fragments by hyaluronidase enzymes, particularly when skin is wounded. The impact of various molecular weight fragments of HA on normal human epidermal keratinocytes (NHEK) with regard to expression of important cellular proteins has not been deeply explored. AIMS: Examination of three molecular weight (Mw) fractions of hyaluronic acid: 1) average Mw of the high fraction: 1.5-2 MDa, 2) average Mw of the medium fraction: 200-500 kDa, and 3) average Mw of the low fraction: 5-10 kDa and a unique 1:1:1 composite complex of the three HA fragments (Triluronic® Acid) was done to examine the influence of the HA on two critical skin cell protein targets: hyaluronan synthase-1 (HAS-1) and the HA binding protein cluster of differentiation 44 (CD44). METHODS: NHEKs were treated in vitro with a 1.0% stock solution of each HA Mw fraction at 1.0, 0.5, and 0.1% concentrations of the 1.0% solution and the polysaccharide composite at the same concentrations for 48 Hrs. The cells were than analyzed by ELISA protein assays for HAS-1 and CD44 protein content. RESULTS: Examination of HAS-1 protein expression indicates that none of the HA test materials influenced the expression of HAS-1 at any concentration. Examination of the CD44 protein expression indicated that the low Mw fraction and the commercial complex of the three Mw fractions upregulated CD44 protein expression in NHEKs, but the medium Mw and high Mw HA fractions did not. CONCLUSIONS: In this work, it was demonstrated that HA can influence the expression of CD44 protein, a critical HA transmembrane HA binding protein, and the influence appears to be molecular weight dependent.