>> Paeonia Suffruticosa
1. Plant-Based Skin Whitening Cosmetics.
Shyam Gupta, Ph.D. Plant-Based Skin Whitening Agents. March 1, 2010.
"Peony (Paeonia suffruticosa): The chemical structure of most plant-based skin whitening agents comprises a dihydroxybenzene (hydroquinone, pyrocatechol or resorcinol) moiety. Butyl resorcinol is known to inhibit melanin synthesis. Kaempferia pandurata contains a skin-whitening agent, isopanduratin; and Alpinia galangal contains galangin—both of these possess a related trihydroxybenzene chemical structure. Dihydroxyacetophenone (resacetophenone) is present in various peony extracts. Resacetophenone can be a good skin-brightening agent that works by inhibiting the formation of tyrosine itself. The topical delivery systems for resacetophenone-based skin brightening and anti-aging cosmetics have been patented (U.S. Patent 7,427,690; 7,572,933; and U.S. Patent Application 20090074691).The role of pH in the formulation development of dihydroxybenzene-based ingredients is very important. Skin-whitening products that contain a dihydroxybenzene moiety should be formulated in the acidic pH range (pH 3.5 to 5.5). The dihydroxybenzene structure is oxidized under alkaline pH conditions in the presence of air. The concomitant use of any oxidizing ingredient should be avoided."
2. Tyrosinase inhibitors isolated from the roots of Paeonia suffruticosa.
Ding HY, Lin HC, Chang TS. Institute of Cosmetics Science, Chia Nan University of Pharmacy and Science, Tainan. 2009 May-Jun;60(3):347-52.
"The inhibition of mushroom tyrosinase by Paeonia suffruticosa root-derived materials was evaluated. Six tyrosinase inhibitors were isolated by ethanol extraction, n-hexane, ethyl acetate, n-BuOH, and water partition, silica gel column chromatography, Sephadex LH-20, Lobar PR-8, and high-performance liquid chromatography methods, and they were identified as kaempferol (I), quercetin (II), mudanpioside B (III), benzoyloxypaeoniflorin (IV), mudanpioside H (V), and pentagalloyl-beta-(D)-glucose (VI) on the basis of spectroscopic evidence. The inhibitory activities of compounds I to VI against mushroom tyrosinase were determined with IC(50) values of 0.120, 0.108, 0.368, 0.453, 0.324, and 0.063 mM, respectively. The kinetic study indicated that all purified inhibitors acted competitively for the L-dopa binding site of the enzyme, with an exception of compound VI, which acted non-competitively."
3. Inhibition of the CXCR3-mediated pathway suppresses ultraviolet B-induced pigmentation and erythema in skin.
R. Kurata, F. Fujita, K. Oonishi, K-I. Kuriyama, S. Kawamata. British Journal of Dermatology. Volume 163, Issue 3, pages 593–602, September 2010.
"Paeonia Suffruticosa Andrews (PSA) pretreatment suppressed SBC formation in the 3D skin model, and erythema formation and pigmentation in volunteers exposed to UVB irradiation. Comprehensive gene analysis after UVB irradiation showed upregulation of CXCR3 and its ligands, CXCL9/monokine induced by interferon (IFN)-y (MIG), CXCL 10/10-kDa IFN-y-induced protein (IP-10) and CXCL11/inducible T-cell alpha-chemoattractant (I-TAC). Upregulation of these genes was partially suppressed by PSA pretreatment. Melanin biosynthesis increased upon stimulation of CXCR3 ligands (MIG, IP-10 or I-TAC) and decreased following CXCR3 downregulation by shRNA knockdown. UVB irradiation activates CXCR3-mediated signalling that leads to melanin synthesis. PSA pretreatment shows a lightening effect partly by attenuating CXCR3-mediated signalling at the transcriptional level."