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Aloe gel is a complex mixture of several components, although it appears to be a simple ingredient that has found consumer applications both as a cosmeceutical and a nutraceutical agent. Many compounds with diverse structures, such as tannins, flavonoids, terpenoids, carbohydrates and alkaloids, have been isolated from A. vera leaves and the exudate arising from the cells adjacent to the vascular bundles. This table contains the chemical composition of A. vera, from A to Z.13–14
“Old is gold,” a familiar proverb in some parts of the world, is an apt way to describe the general consumer preference for well-known skin care ingredients, despite being “old” from a marketing story point of view. The infusion of enhanced performance into such ingredients brings new life both from the vantage of innovative marketing and renewed consumer interest. Aloe is such an example: New derivatives of aloe components and their delivery systems discussed in this article are expected to pave the way for a renewed interest in novel skin care applications of these “super aloe” agents from old aloe.
Aloesin, a compound isolated from the aloe plant, possesses multiple skin care benefits. For example, enzyme kinetics studies using normal human melanocyte cell lysates and cell-based melanin production demonstrated that aloesin is a competitive inhibitor of tyrosinase, which catalyzes the production of melanin, from mushroom, human and murine sources. Tyrosine hydroxylase and 3,4-dihydroxyphenylalanine (DOPA) oxidase activities of tyrosinase from normal human melanocyte cell lysates were inhibited by aloesin in a dose-dependent manner.1–7 In addition, aloesin is an antioxidant and anti-inflammatory agent.8–10
In a percutaneous absorption study, a finite dose of aloesin penetrated the skin slowly and was recovered primarily in the surface wash. Aloesin, thus, shows promise as a pigmentation-altering agent for cosmetic or therapeutic applications, though its poor topical bioavailability1–7 requires additional consideration of delivery systems; and it also is clear, therefore, that multiple skin care benefits of aloesin can be improved further via enhanced skin delivery.
Aloesin complexes with synergistic skin care agents provide a new topical delivery system for aloesin—as well as synergy from the complex-forming agent, for example, skin-brightening, antioxidant and anti-inflammatory benefits.11, 12
The compatible solute aloesin found naturally in aloe vera has been widely researched as having anti-inflammatory, antioxidant and melanogenesis-inhibition activity. However, poor topical bioavailability has prevented its emergence into beauty care. Novel aloesin derivatives with amino acids, peptides, amino sugars and vitamin C analogs have been invented to optimize aloesin’s activity and improve its bioavailability for purposes of treating conditions associated with aging skin. These derivatives should prove to bridge the gap that has prevented this amazing active compound from sharing the limelight with some of the better-known and widely accepted topical actives like retinoids and peptidic fractions.
Aloesin and the described aloesin derivatives are easily marketable to both natural and science-savvy consumers. On one hand, you have a natural compound derived from a source that most consumers are comfortable with, aloe vera; on the other, you have an active molecule that has been extensively researched since its discovery, aloesin. Moreover, the aforementioned derivative provides action and functionality familiar to today’s consumer—DNA repair and protection via antioxidation, skin brightening via melanogensis inhibition, anti-aging and anti-wrinkle via MMP inhibition to name a few.
At the end of the day, ingredient and formulating science and the outcomes, notably those that create a synergy of nature and science-backed efficacy, provide brands with a marketing message that can be used to demystify the introduction of skin care products that contain an aloesin derivative to the beauty marketplace.
Shyam Gupta is a consultant in skin and hair care ingredients and topical delivery systems. He specializes in nature-and science-based formulations with enhanced efficacy and consumer-desirable performance attributes. 1-602-996-9700; firstname.lastname@example.org; www.biodermresearch.com
John Stanek is manager of new technologies and product development at CoValence Laboratories. His primary responsibility is to research new technologies leading to new product concepts. 1-480-897-0551; email@example.com; www.covalence.com