154 J. Cosmet. Sci., 73, 154–165 (May/June 2022) Address all correspondence to Quan An, anquan@ynbyjk.com The Antipigmentation and Antioxidant Activity of Sanchi Flower Extract JUAN WANG, PEIYU WANG, XUE SHAO, TONG HUO, JITAO LIU, QIANGHUA QUAN AND QUAN AN Yunnan Baiyao Group Health Products Co., Ltd., Kunming, Yunnan, P.R. China (J.W., P.W., X.S., T.H., J.L., Q.Q., Q.A.) East Asia Skin Health Research Center, Beijing, P.R. China (J.W., P.W., X.S., T.H., Q.Q., Q.A.) REAL DermaSci & Biotech Co., Ltd., Beijing, P.R. China (J.W., P.W., T.H., Q.Q., Q.A.) Yunnan Baiyao Group Shanghai Science & Technology Co., Ltd., Shanghai, P.R. China (J.L., Q.A.) Accepted for publication June 20, 2022. Synopsis Long-term ultraviolet (UV) irradiation stimulates melanogenesis by direct effects on melanocytes and by indirect effects on keratinocytes releasing melanogenic factors. Hyperpigmentation is a major cosmetic concern. Thus, melanin synthesis inhibitors are popularly used as brightening agents in cosmetics. It has been reported that Sanchi flower extract (SFE) exerts various biological effects including hypotensive, hemostatic, and anti-aging activities. The authors explored the potential of SFE as a cosmetic ingredient. On the one hand, it could significantly inhibit melanin production both in B16-F0 cells and in the three-dimensional skin model. In addition, intracellular tyrosinase activity decreased after treatment with SFE. On the other hand, it upregulated cellular glutathione peroxidase activity and total antioxidant capacity in HaCaT cells irradiated with UVB radiation in contrast to the model group. These results indicated that SFE showed obvious antipigmentation potency and alleviated oxidative stress caused by UVB. INTRODUCTION Sanchi, as a famous and precious Chinese medicine, has been commonly used throughout history as an alternative remedy. It has been used for medicinal purposes to promote blood circulation, relieve swelling and pain, and counteract blood stasis (1). Its various parts— including roots, flowers, and leaves—are used for producing medicinal formulations. The main active ingredients of Sanchi are composed of saponins, amino acids (2), flavonoids, and polyphenols, which display strong antioxidant activity and anti-inflammatory potency (3). However, the antimelanogenesis and skin-protective effects of Sanchi flower extract (SFE) are rarely reported.

155 ANTIPIGMENTATION AND ANTIOXIDANT ACTIVITY Environmental exposure factors mainly include air pollution, ultraviolet (UV) irradiation, and multifarious physical and chemical stimulation These trigger many skin problems, such as skin hyperpigmentation, dryness and aging, and so forth (4). Pigmentation is a key factor in determining skin color, as well as one of the defense systems that protects skin from UV damage (5). Melanogenesis is a complex biological synthesis that includes melanocyte proliferation, melanin production, and melanosome transfer to keratinocytes. UV exposure can activate tyrosinase and promote melanin synthesis in melanocytes (6), leading to hyperpigmentation and skin disorders. The copper-containing enzyme tyrosinase is a key rate-limiting enzyme in melanin biosynthesis, which catalyzes the production of melanin through oxidation of L-tyrosine to L-dihydroxyphenylalanine (L-DOPA) and dopaquinone (7). Subsequently, L-DOPA is converted to either eumelanin or pheomelanin, depending on its reaction with cellular cysteine or dopachrome tautomerase and tyrosinase-related protein 1 (8). UV irradiation stimulates excessive reactive oxygen species (ROS) generation through alteration in cellular metabolism, which breaks down the cellular antioxidant defense system and triggers oxidative stress (9). DNA damage, lipid peroxidation, and apoptotic signal transduction are triggered, clarifying these thoughts owing to the oxidative imbalance and further influencing cellular physiological function (10). The accumulation of lipofuscin and melanin caused by superfluous ROS can turn into senile plaques, melasma, dark spots, and other pigmented skin diseases (11), eventually leading to skin photoaging and skin cancer. However, skin cells can upregulate cellular antioxidant capacity through glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), superoxide dismutase, catalase, and nonenzymatic mechanisms in order to maintain a normal physiological environment (12). The authors evaluated the inhibitory ability of SFE for melanin production at the cellular level and even in the reconstructed melanin skin model. Its antioxidant capacity was also assessed. The double effects of SFE indicated that it had the potential to become an effective cosmetic ingredient. MATERIALS AND METHODS MATERIALS Dried SFE was collected from Yunnan Baiyao Group Health Products Co., Ltd (Kunming, Yunnan, China). Dulbecco’s Modified Eagle Medium (DMEM) (Corning®, Corning, New York), penicillin, streptomycin, and fetal bovine serum (FBS) were purchased from Gibco (Waltham, Massachusetts). Other chemicals were from Servicebio (Hubei, China). MelaKutis® (Biocell Biotechnology, Guangdong, China) was manufactured by Biocell Biotechnology (Dongguan, Guangdong, China). CELL VIABILITY Cytotoxicity of SFE to B16-F0 and HaCaT cells. B16-F0 cells were seeded at 2 × 104 cells per well, and HaCaT cells were placed at 2 × 105 cells per well in DMEM complete medium in 96-well plates. They were cultured in a humidified environment at 37°C and 5% CO 2 for 24 hours and then treated with SFE in serum-free DMEM for 48 hours (13). Cell viability was measured by the cell counting kit (CCK)-8 assay. Both B16-F0 and HaCaT cells were incubated with 10 µL CCK-8 solution per well for 2.5 hours, and absorbance was measured at 450 nm by the Thermo Fisher Scientific (Waltham, Massachusetts) microplate reader.