Depigmentation of Melanocytes by Isopanduratin A and 4-Hydroxypanduratin A Isolated from <i>Kaempferia pandurata</i> R<small>OXB</small>.

Abstract

Melanin is the phenolic biopolymer that is responsible for pigmentation. Although melanin plays a crucial role in absorbing free radicals from the cytoplasm and shielding from UV light, the overproduction and accumulation of melanin in the skin could be a serious skin disorder. 1) Current therapies for skin pigmentation disease are unsatisfactory. Thus the search for natural and synthetic chemical agents to modulate the metabolism of pigmentation is of great interest. 2)Melanin biosynthesis occurs in a cascade of enzymatic and spontaneous reactions that convert tyrosine to melanin pigments.3) The initial and rate-limiting step in melanin synthesis, the hydroxylation of tyrosine to dihydroxyphenylalanine (DOPA), is controlled by tyrosinase that is the key enzyme in the process. 4) Since the 1980s, skin cancer researchers have studied the melanin biosynthetic pathways, which led to the development of whitening cosmetics and medicines.5) Arbutin, kojic acid, hydroquinone and its derivatives were developed in 1980s.6) However, the clinical effects of those chemicals are unsatisfactory because of their low activity and cell toxicity. 7) Therefore there is a need for safe and effective whitening agents.Kaempferia pandurata ROXB. is a perennial herb of the Zingiberaceae family mainly cultivated in tropical countries, including Indonesia and Thailand. The fresh rhizome has been used as a food ingredient and as a folk medicine for the treatment of colic, dry cough, rheumatism, musle pain, and as an aphrodisiac.8) Several studies reported various activities of K. pandurata, including antiinflammatory, antitumor, antidiarrhea, antidysentery, antiflatulence, and antiepidermophytid effects. 9) Isopanduratin A and 4-hydroxypanduratin A (Fig. 1) are the typical chalcone compounds found in K. pandurata. Chalcones belong to a group of phenolic compounds in the flavonoid family and widely occur in nature as pigments. This category of flavonoids has a broad bioactive spectrum such as anticancer, antibacterial, antifungal activities, etc. [10][11][12] In previous studies, chalcone compounds in K.pandurata showed anticancer, antioxidative, antimutagenic, and antibacterial activities. [13][14][15] However, their depigmenting effect has not yet been examined. Therefore we focused on evaluating the inhibitory effects of chalcone compounds isolated from K. pandurata on melanin biosynthesis and tyrosinase. Seocheon-dong, Giheung-gu, Yongin-si, Gyeonggi-do 446-701, South Korea: and c R&D Center, Amore-Pacific Corporation; 314-1, Bora-dong, Kiheung-gu, Yongin-si, Kyounggi-do 449-729, South Korea. Received April 11, 2007; accepted July 20, 2007 This study was carried out to investigate the in vitro effects of isopanduratin A and 4-hydroxypanduratin A isolated from Kaempferia pandurata ROXB. on melanin biosynthesis and tyrosinase activity. Two chalcone compounds, isopanduratin A and 4-hydroxypanduratin A, were isolated from the ethyl acetate fraction of ethanol extract as the active principles. Compared with phenylthiourea (IC 50 ‫3.4...

Boesenbergia rotunda

“…Studies in Korea reported that two chalcone compounds, isopanduratin A and 4-hydroxypanduratin A, isolated from the ethyl acetate fraction of ethanol extract of Kaempferia pandurata exhibited inhibitory effect on melanin biosynthesis and tyrosinase activity (Yoon et al 2007 ). Compared with phenylthiourea (IC 50 = 34.3 μM) as a positive control, the depigmentation IC 50 values for isopanduratin A and 4-hydroxypanduratin A were 10.6 μM and 23.2 μM, respectively.…”

Determination of Antioxidant and Anti-Melanogenesis Activities of Indonesian Lai, <i>Durio kutejensis</i> [Bombacaceae (Hassk) Becc] Fruit Extract

“…The initial and rate-limiting step in melanin synthesis is the hydroxylation of tyrosine to dihydroxyphenylalanine or DOPA [3]. DOPAoxidation produces a highly reactive intermediate that is further oxidized to form melanin by a free radical-coupling pathway.…”

Effects of isolated compound from Sonneratia caseolaris leaf: a validation of traditional utilization by melanin biosynthesis and antioxidant assays

“…Email: tangkearung@yahoo.com **Kuniyoshi Shimizu, Address: Kyushu University, Fukuoka, Melanin biosynthesis occurs in a cascade of enzymatic and spontaneous reactions that convert tyrosine to melanin pigments. The initial and rate-limiting step in melanin synthesis is the hydroxylation of tyrosine to dihydroxy-phenylalanine or DOPA (Yoon et al, 2007). DOPA-oxidation produces a highly reactive intermediate that is further oxidized to form melanin by a free radical-coupling pathway.…”

“…The initial and rate-limiting step in melanin synthesis is the hydroxylation of tyrosine to dihydroxy-phenylalanine or DOPA (Yoon et al, 2007). DOPA-oxidation produces a highly reactive intermediate that is further oxidized to form melanin by a free radical-coupling pathway.…”