J. Cosmet. Sci., 66, 219–231 (July/August 2015) 219 Potential of native Thai aromatic plant extracts in antiwrinkle body creams PIMPORN LEELAPORNPISID, R. RANDALL WICKETT, SUNEE CHANSAKAOW, and NITIMA WONGWATTANANUKUL, Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, Chiang Mai, Thailand (P.L., S.C., N.W.), and James L. Winkle College of Pharmacy, University of Cincinnati, OH (R.W.). Accepted for publication May 30, 2015. Synopsis Antioxidant activities of 10 essential oils and 10 absolutes extracted from Thai aromatic plants were evaluated and compared to thyme oil, trolox, quercetin, and kaempferol by two independent assays: the 2, 2-diphenyl- 1-1-picrylhydrazyl (DPPH•) radical scavenging assay and the thiobarbituric acid reactive species (TBARS) assay for lipid peroxidation. We found that four essential oils including ginger oil (Zingiber offi cinale Roscoe), Wan-sao- long leaf oil (Amomum uliginosum Koen), lemongrass oil (Cymbopogon citratus), holy basil oil (Ocimum sanctum L.), and the absolute of dwarf ylang-ylang [Cananga odorata Hook. f. & Thomson var. fruticosa (Craib) J. Sinclair] exhibited high antioxidant activity in both DPPH and TBARS assays and possessed satisfactory fragrance prop- erties. These were then combined into an essential oil blend (EOB) and retested for antioxidant activity. The EOB also exhibited high antioxidant activity in the above assays. It was then incorporated into a stable cream base as EOB body cream. The EOB body cream was found to be best able under storage in stress conditions and pre- sented signifi cantly higher antioxidant activity than its’ cream base both before and after stability testing. The effect of EOB body cream on skin surface topography was evaluated in 29 healthy volunteers using the Skin Visiometer® (SV 600 FW, CK Electronic GmbH, Germany). Three parameters, Ra, Rz (roughness), and surface, were analyzed. After 4 weeks of application, the EOB body cream showed signifi cant reductions in surface and Rz compared with before treatment (p 0.05, paired t-test), and with untreated and placebo treatment (p 0.05, Duncan test). These results indicate that the essential oils and absolutes from Thai plants may serve as potential sources of natural antioxidants for spa and cosmetic products designed to prevent or treat signs of skin aging. INTRODUCTION The recent resurgence of “back to nature” themes and consumer preference for natural health and beauty solutions have refocused attention on the healing power of indigenous herbs and plants—a key component in the ancient Thai tradition of natural healing. Thailand has great diversity of herbs and spices and continues to provide a rich assort- ment of natural ingredients for exotic herbal preparations. Many of the rejuvenating Address all correspondence to Randall Wickett at randy.wickett@uc.edu.

JOURNAL OF COSMETIC SCIENCE 220 treatments offered in modern spas have evolved from these ancient recipes. There is a clear consensus that, spa treatments may go beyond superfi cial pampering. Holistic heal- ing is central to the spa concept. Antioxidant compounds have been found in numerous plant materials including seeds, oils, grains, vegetables, fruits, leaves, bark, roots, and waxes. Most of the plant antioxi- dants fall into the category of polyphenols or fl avonoids. Essential oils and plant extracts are good sources of natural antioxidants. A number of studies on antioxidant activities of essential oils and plant extracts from some aromatic plants have been reported such as ylang-ylang (1,2), turmeric (3,4), lemongrass (1,5), and ginger extracts (1,6) Confi rm all citation. Currently, the spa business is growing rapidly around the world. As spa op- erators feel the pressure of mounting competition and strive to differentiate to survive and excel, an increasing number of Thai spas are developing their own lines of product that capture the exotic qualities of Thai herbs. This has contributed to a renewal of tradi- tional Thai herbal recipes long prized for the healing potency of the natural ingredients from which they are made. Creating a new line of antiaging spa products from Thai aro- matic plants through scientifi c principles is thus an important challenge. The aging process encompasses progressive physiological changes in an organism that lead to senescence, the decline of biological functions, and the organism’s ability to adapt to metabolic stress with time (7). There are many theories that explain the aging process. Since the “free radical theory of aging” was formulated by Dr. Denham Harman in 1956, free radi- cals have been widely accepted to contribute to aging. This theory postulates that aging is accelerated by free radical reactions associated with environmental infl uences, disease, fail- ures of the antioxidant defense, and the intrinsic aging process. Free radicals are highly reac- tive chemical species carrying an unpaired electron in their outer orbit. They abstract electrons from the surrounding molecules (lipids, proteins, and DNA) to complete their own electron structure, thus inducing molecular and cellular damage. Such reactions are strongly implicated in the development of pathogenesis of chronic diseases as atherosclero- sis, diabetes, rheumatoid arthritis, skin and neurodegenerative disorders, cancer, as well as in the aging process. As reported at the 3rd Monte Carlo Anti-Aging ConferenceTM in September 2002, the intrinsic (genetically determined) and the extrinsic [ultraviolet (UV)- and toxic exposure–mediated] skin aging processes overlap and are strongly related to an increased generation of free radicals in the skin. The skin photoaging process, in the presence of natural sunlight or artifi cial UV sources, happens continuously and leads in time to dry- ness, deep wrinkles, sagging, loss of elasticity, mottled pigmentation, and telangiectasia (8). Use of antioxidants such as α-tocopherol, ascorbic acid, and polyphenol compounds may be an effective way to slow down skin aging (9,10). Essential oils and aromatic plant extracts are good sources of natural antioxidants (1–3,5,6). The goal of this study was to develop extracts selected from Thai aromatic plants that exhibited high antioxidant ac- tivity with satisfactory fragrance properties into a prototype product for antiaging body treatments. MATERIALS AND METHODS CHEMICALS AND PLANT MATERIALS The 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2-thiobarbituric acid 98% (TBA), t-octyl- phenoxypolyethoxyethanol (Triton X-100), and butylated hydroxytoluene (BHT) were