BACKGROUND: Phytoclear-EL1, an extract from Euphorbia lathyris seeds, has a whitening effect due to inhibition of tyrosinase activity. OBJECTIVE: The purpose of this study was to investigate the inhibitory effect of phytoclear-EL1 on melanogenesis. METHODS: Cultured B-16 melanoma cells and 30 human volunteers were used for in vitro and in vivo studies, respectively. Phytoclear-EL1 was added to the cultured B-16 melanoma cells, and applied to UVB-induced hyperpigmented lesions of human volunteers twice daily for 7 weeks. Changes in the number of B-16 melanoma cells, as well as changes in morphology, melanin content, and tyrosinase activity, were measured and then compared with the normal control and the 10(-3)M arbutin groups. Also, the effect of phytoclear-EL1 on UVB-induced hyperpigmented lesions was examined through subjective and objective measurements. RESULTS: In the in vitro study (p<0.05), the number, melanin content, and tyrosinase activity of cultured B-16 melanoma cells were decreased in the 5microgram/ml phytoclear-EL1 group compared to the control group. On objective assessment with a chromameter, the 0.2% phytoclear-EL1 group had a larger difference in the mean L values before and 7 weeks after applying phytoclear-EL1 as compared to the other groups. On subjective assessment by both the researchers and subjects 7 weeks after applying experimental materials, the 0.2% phytoclear-EL1 group and positive control (3% arbutin) had higher scores than the placebo groups. These results demonstrated that phytoclear-EL1 in vivo and in vitro had an inhibitory effect on melanogenesis. CONCLUSION: Phytoclear-EL1 may be a candidate extract in the control of hyperpigmentary disorders.
Arbutin ; Euphorbia ; Human Experimentation ; Melanins ; Melanoma ; Monophenol Monooxygenase ; Seeds

OBJECTIVETo determine arbutin contents in different populations of Bergenia purpurascens in Yunnan province, for screening out the best resource and best part of B. purpurascens.

METHODThe SB-C18 column was used with methanol-water (15: 85) as the mobile phase, at the flow rate of 1 mL x min(-1) and column temperature of 30 degrees C, and 282 nm was selected as the detected wavelength.

RESULTThere were much significant differences in arbutin contents among various parts of the same B. population. The sequence of parts from high to low was lamina > petiole > root > rhizome. Arbutin contents in laminae of different B. populations were different at the most significant level and varied between 6.36% and 1.51%. Arbutin contents in rhizomes of different B. populations were also dignificantly different at varied between 1.72% and 0.40%.

CONCLUSIONLamina is the best part for extracting arbutin. B. population distributed in Laojunshan mountain in Lanping county is the best resource for arbutin exploitation in B. purpurascens.

Arbutin ; analysis ; China ; Plant Extracts ; analysis ; Saxifragaceae ; chemistry

Melanin is produced in melanocytes and stored in melanosomes. In spite of its beneficial sun-protective effect, abnormal accumulation of melanin results in esthetic problems. Hydroquinone, competing with tyrosine, is a major ingredient in topical pharmacological agents. However, frequent adverse reactions are amongst its major limitation. To solve this problem, several alternatives such as arbutin, kojic acid, aloesin, and 4-n-butyl resorcinol have been developed. Herein, we classify hypopigmenting agents according to their mechanism of action; a) regulation of enzyme, which is subdivided into three categories, i) regulation of transcription and maturation of tyrosinase, ii) inhibition of tyrosinase activity, and iii) post-transcriptional control of tyrosinase; b) inhibition of melanosome transfer, and c) additional mechanisms such as regulation of the melanocyte environment and antioxidant agents.
Arbutin ; Chromones ; Glucosides ; Hydroquinones ; Hypopigmentation ; Melanins ; Melanocytes ; Melanosomes ; Monophenol Monooxygenase ; Pyrones ; Resorcinols ; Tyrosine

BACKGROUND: Arbutin is a glycosylated hydroquinone found at high concentration in certain plants capable of surviving extreme and sustained dehydration. It has been suggested as an inhibitory compound of melanogenesis. OBJECTIVE: The purpose of this study was to investigate the effect of arbutin on melanogenesis in cultured human melanocytes and to evaluate the effectiveness of arbutin in patients with melasma. METHODS: I. In vitro study:we examine the cell number, SRB assay, tyrosinase activity, and melanin contents of cultured human melanocytes in control(absence of arbutin) and experimental groups (presence of 10(-5) M, 10(-4) M, and 10(-3) M arbutin). II. In vivo study:6 patients with melasma applied a 3 % arbutin solution twice daily for 8 weeks. Clinical response to treatment was evaluated by patients' subjective assessment and MASI(Melasma Area and Severity Index) score after 8 weeks of treatment. RESULTS: I. In vitro study 1. The number of melanocytes was decreased in groups treated with 10(-5) M, 10(-4) M, 10(-3) M arbutin for 2 days and 10(-4) M, 10(-3) M arbutin for 7 days. 2. On SRB assay, the proliferation of melanocytes was decreased in groups treated with 10(-5) M, 10(-4) M, 10(-3) M arbutin for 2 days and for 7 days. 3. Tyrosinase activity was decreased in groups treated wtih 10(-4) M, 10(-3) M arbutin for 2 days and 10(-5) M, 10(-4) M, 10(-3) M arbutin for 7 days. 4. The melanin contents were decreased in group treated with 10(-3) M arbutin for 7 days. II. In vivo study 1. On patients'subjective assessment, one showed moderate improvement, one showed mild improvement, and the other four showed no change. 2. On MASI score, there was less than 10% improvement in all 6 patients. 3. Side effects were not found in all 6 patients. CONCLUSION: Although arbutin showed an inhibitory effect on cell proliferation, tyrosinase activity, and melanin synthesis in cultured human melanocytes, there was no significant effect of depigmentation in the patients with melasma.
Arbutin* ; Cell Count ; Cell Proliferation ; Dehydration ; Humans ; Melanins ; Melanocytes ; Melanosis ; Monophenol Monooxygenase

The half-dried leaves of Stewartia. pseudocamellia were extracted with hot water (SPE) and partitioned with n-hexane (SPEH), dichloromethane (SPED), and ethyl acetate (SPEE) successively. SPE and SPEE showed significant inhibitory effects against melanogenesis and tyrosinase activities. By bioassay-guided isolation, ten phenolic compounds were isolated by column chromatography from SPEE. The whitening effect of the isolated compounds from SPEE were tested for the inhibitory activities against melanogenesis using B16 melanoma cells, in vitro inhibition of tyrosinase, and L-3,4-dihydorxy-indole-2-carboxylic acid (L-DOPA) auto-oxidation assay. A cytotoxic activity assay was done to examine the cellular toxicity in Raw 264.7 macrophage cells. Of the compounds isolated, gallic acid and quercetin revealed significant inhibitory activities against melanogenesis compared to arbutin. In particular, quercetin exhibited similar inhibitory activities against tyrosinase and L-DOPA oxidation without cytotoxicity. These results suggested that SPE could be used as a potential source of natural skin-whitening material in cosmetics as well as in food products.
Arbutin ; Chromatography ; Gallic Acid ; Levodopa ; Macrophages ; Melanoma, Experimental ; Methylene Chloride ; Monophenol Monooxygenase ; Phenol* ; Quercetin ; Water

AIMTo study the chemical constituents of Breynia rostrata Merr.

METHODSChromatography was used to isolate and purify the chemical constituents, their structures were identified by spectral analysis.

RESULTSFour glycosides were identified as 6-O-methylpropanoyl-alpha-D-glucopyranoside (1), 4"-phenolic-6-O-methylpropanoyl-beta-D-glucopyranoside (2), 1-O-galloyl-beta-D-glucopyranoside (3), arbutin (4).

CONCLUSIONCompounds 1 and 2 are new compounds; 3 and 4 were isolated from Breynia rostrata Merr. for the first time.

Arbutin ; chemistry ; isolation & purification ; Euphorbiaceae ; chemistry ; Molecular Structure ; Monosaccharides ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry

BACKGROUND: Melanocytes synthesize melanin pigment by the action of specific enzyme tyrosinase. Melanogenesis inhibitors such as ascorbic acid, kojic acid, arbutin, hydroquinone have been developed for use in cosmetic preparations for the skin hyperpigmentation,but they are still unsatisfactory to efficacy and tolerance. OBJECTIVES: In this study, the inhibitory effects of seaweed extract(SCH-T2)on tyrosinase activity and melanogenesis were investigated with B-16 melanoma cell line. METHODS: The patients were randomly assigned to one of three groups;control, diazepam, and ketorolac plus diazepam groups. Pain intensity was assessed 5 times at every ten minutes from the beginning of the peeling using visual analog scale(VAS). RESULTS: The seaweed was added with 21 organic solvents and extracted during 12 hours at 20-To evaluate the inhibitory effects of SCH-T2 on tyrosinase activity following to extraction time and temperature, this study was done at 4, 8, 12, 24, 72 hours and 4, 10, 20, 30, 40℃. Also, the effects of whitening agents (kojic acid, arbutin, licorice extracts,SCH-T2)on tyrosinase activity were compared by measuring the IC50,the concentration of the compound at which half of the original tyrosinase activity is inhibited. RESULTS: 1.The inhibitory effects of SCH-T2 on tyrosinase activity were high at 60-80% ethanol as an extraction organic solvent and showed increase in proportion to concentration following to extract concentration, but showed little differences following to extraction time and temperature. 2.SCH-T2 has relatively stronger inhibitory effects on tyrosinase activity than arbutin and licorice extracts. 3. The inhibitory effects of SCH-T2 on melanogenesis following to extract concentration were greatly increased at more than 20㎍/ml. CONCLUSION: This study showed that SCH-T2 seaweed extract has strong inhibitory effect on tyrosinase activity and melanogonesis. So, the results of this study suggest that SCH-T2 seaweed extract can be used as a new whitening agent.
Arbutin ; Ascorbic Acid ; Bleaching Agents ; Cell Line ; Diazepam ; Ethanol ; Glycyrrhiza ; Humans ; Ketorolac ; Melanins ; Melanocytes ; Melanoma ; Monophenol Monooxygenase ; Seaweed* ; Skin ; Solvents

BACKGROUND: Plant extracts have been widely used as important therapeutic drugs for many centuries all over the world. There have been many reports that natural products have various kinds of biological activities such as anti-allergy, anti-inflammatory and antimicrobial activities. Recently, the screening for the efficacy and safety of natural products has been extensively performed. OBJECTIVE: This study was carried out to find a beneficial plant extract possessing excellent antioxidative and anti-melanogenic activities. We have found that the leaf of Robinia pseudo-acacia L. has active substances which are involved in those activities. METHODS: To confirm the antioxidative activity of the extract obtained from the leaves of Robinia pseudo-acacia L., scavenging ability of the extract on DPPH free radicals and its inhibitory effects on lipid autoxidation and peroxidation were investigated. In addition, inhibitory effects of the extract on mushroom tyrosinase as well as melanin biosynthesis in cultured B16 melanoma cells were evaluated. RESULTS: The acacia extract showed not only powerful antioxidative activity but also antimelanogenic acitivity as strong as that of arbutin which is a well known inhibitor of melanogenesis. CONCLUSION: These resulis suggest that the extract from the leaves of Robinia pseudo-acacia L. could be used as a 4ghtening and antioxidative agent for the skin.
Acacia ; Agaricales ; Arbutin ; Biological Products ; Free Radicals ; Mass Screening ; Melanins ; Melanoma, Experimental ; Monophenol Monooxygenase ; Plant Extracts ; Plants ; Robinia* ; Skin

BACKGROUND: Melanin pigmentation plays a major role in normal skin color. The rates of melanin synthesis by melanocytes appear to be regulated by ultraviolet-B(UVB) radiation and chemicals, though the precise mechanisms modulating human epidermal pigmentation are unknown. Several chemicals including arbutin kojic acid(KA), pentadecenoic acid (PDA) and glycolic acid (GA) have been suggested as a meanogenesis inhibitory compounds because of their chemical or biological similarties with hydroquinone or their tyrosinase inhibitory effect. OBJECTIVE: The purpose of this study was to evaluate the inhibitory effect of arbutin, GA, KA and PDA on UV-induced melanogenesis in the vitro and in vivo pigmentary system. METHODS: Cultured normal melanocytes and B-16 melanoma cells, and C57BL mice and human volunteers were used for in vitro and in vivo studies respectively. They were administered to UVB irradiated or nonirradiated cultured normal human melanocytes, and B-16 melanoma cells. For the in vivo study, these chemicals were topically applied to C57BL mice and human volunteer skin after UVB irradiation, Numeric and morphologic changes and melanin content were measured in cultured normal human melanocytes and B-16 melanoma cells. In the C57BL mice, numeric and morphologic changes of split-COPA stained melanocytes were assessed. In the human volunteers, gross pigementary changes were evaluated. RESULTS: 1. The number and melanin content of cultured melanocytes initially decreased after UVB-irradiation, but the melanin content increased 5 days after irradiation. 2. Cell numbers of irradiated or nonirradiated cultured human melanocytes decreased in arbutin(10-3M), KA(10-3M, 10-5M), PDA(10-3M) groups. Those of the cultured B-16 melanoma cells decreased only in the arbutin(10-3M) group after UVB irradiation. 3. Melanin contents of cultured human melanocytes decreased in arbutin(10-3M, 10-5M), KA(10-3M, 10-5M) and PDA(10-3M) groups. Those of cultured B-16 melanoma cells decreased in arbutin(10-3M, 10-5M) groups after UVB-irradiation or nonirradiation. 4. The number of split-DOPA(+) melanocytes decreased in the groups treated with KA 1% for 3, 5 and 7 weeks, KA 0.1%, arbutin 3%, arbutin 5% for 5 and 7 weeks and PDA 5.0% for 7 weeks in the C57BL mice. 5. The number of split-DOPA(+) melanocytes decreased in the groups treated with KA 1.0%, PDA 5.0%, arbutin 3% and arbutin 5% for 5 and 7 weeks and KA 0.1% for 7 weeks in UVB irradiated C57BL mice. 6. Visible inhibition of UVB-induced yperpigmentation was observed in arbutin applied sites in 4 of the 6 volunteers 3 weeks after the application. GA did not show an inhibitory effect on UVB-induced hyperpigmentation in all subjects. CONCLUSION: Arbutn, KA, PDA had a suppressive effect on melanization of nonirradiated melanocytes and melanoma cells as well as UVB-induced hyperpigmentation. It is suggested that these drugs might be candidates as compounds that may control hyperpigmentary disorders.
Animals ; Arbutin* ; Cell Count ; Healthy Volunteers ; Humans ; Hyperpigmentation ; Melanins ; Melanocytes ; Melanoma ; Mice ; Mice, Inbred C57BL ; Monophenol Monooxygenase ; Pigmentation ; Skin ; Volunteers

BACKGROUND: Melanoston is a new melanogenesis inhibitor isolated from yeast. However, little is known about the mechanism of this agent in melanogenesis and also its clinical effectiveness on hyperpigmented lesions. OBJECTIVE: The purpose of this study was to examine the inhibitory effect of melanoston on in vivo activity of tyrosinase. METHODS: We assessed tyrosinase activity, which participates in the synthesis of melanin pigment and resides in melanocytes of guinea pig's epidermis, using immunohistochemical methods after application of 0.1% and 0.01% melanoston on the skin of guinea pigs. We also conducted an 8-week clinical trial on 30 women volunteers to determine the clinical efficacy and safety of melanoston. Participants were instructed to apply melanoston and vehicle on 7 small areas of skin on both forearms for 8 weeks, before and after UVB exposure, and they were examined daily for the first week, then weekly thereafter. RESULTS: The lowest level of tyrosinase activity was observed at the 3rd week after application of 0.1% and 0.01% melanoston on the skin of guinea pigs, and melanoston had a relatively strong inhibitory effect on tyrosinase, as compared with vehicle and arbutin. Differences in the degree of pigmentation between areas treated with 0.5% melanoston and application of vehicle only, and between before and after UVB exposure were considered to be significant (p<0.001, on each time). CONCLUSION: We conclude that melanoston has an inhibitory effect on melanogenesis and some eliminating effect on preexisting pigmentation.
Animals ; Arbutin ; Epidermis ; Female ; Forearm ; Guinea ; Guinea Pigs ; Humans ; Melanins ; Melanocytes ; Monophenol Monooxygenase ; Pigmentation* ; Skin ; Volunteers ; Yeasts