Phytochemical investigation of the stems of Pueraria lobata (Wild) Ohwi (Leguminosae), led to the isolation of eighteen known compounds: β-amyrone (1), (+)-pinoresinol (2), (+)-syringaresinol (3) (+)-syringaresinol-O-β-D-glucoside (4), (+)-lariciresinol (5), (-)-tuberosin (6), naringenin (7), liquiritigenin (8), isoliquiritigenin (9) genistein (10), daidzein (11) daidzin (12) daidzein 4',7-diglucoside (13) 2,4,4'-trihydroxy deoxybenzoin (14), S-(+)-1-hydroxy-3-(4-hydroxyphenyl)-1-(4-hydroxy-2-methoxy-phenyl)propan-2-one (15), methyl 2-O-β-D-glucopyranosylbenzoate (16), pyromeconic acid 3-O-β-D-glucopyranoside 6'-(O-4''-hydroxy-3-methoxybenzoate) (17), and allantion (18). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of those data with previously published results. The effects of isolated compounds on mushroom tyrosinase enzymatic activity were screened. The results indicated that, chloroform extract of P. lobata stems turned out to be having tyrosinase inhibitory effect, and only compounds 5, 8, 9, and 11 showed enzyme inhibitory activity, with IC₅₀ values of 21.49 ± 4.44, 25.24 ± 6.79, 4.85 ± 2.29, and 17.50 ± 1.29 µM, respectively, in comparison with these of positive control, kojic acid (IC₅₀ 12.28 ± 2.72 µM). The results suggest that P. lobata stems extract as well as its chemical components may represent as potential candidates for tyrosinase inhibitors.
Agaricales ; Chloroform ; Fabaceae ; Genistein ; Monophenol Monooxygenase* ; Pueraria*

This study is aimed to evaluate skin whitening effects of Sanguisorba officinalis and Stichopus japonicus for cosmeceutical ingredients. The extract of Stichopus japonicus showed 61.78% inhibition of tyrosinase activity, and the mixture of Sanguisorba officinalis extract and Stichopus japonicus extract showed 59.14% inhibition of tyrosinase activity. On the clone M-3 cell meloanocyte, the mixture of Sanguisorba officinalis extract and Stichopus japonicus extract showed remarkable inhibition of melanogenesis. Also, those extracts were not irritable in ocular irritation test. It is concluded from these results that Sanguisorba officinalis and Stichopus japonicus have skin whitening effect. It could be used as natural depigmental material in cosmeceutical ingredients.
Clone Cells ; Monophenol Monooxygenase ; Sanguisorba ; Skin ; Stichopus

This study is aimed to evaluate skin whitening effects of Sanguisorba officinalis and Stichopus japonicus for cosmeceutical ingredients. The extract of Stichopus japonicus showed 61.78% inhibition of tyrosinase activity, and the mixture of Sanguisorba officinalis extract and Stichopus japonicus extract showed 59.14% inhibition of tyrosinase activity. On the clone M-3 cell meloanocyte, the mixture of Sanguisorba officinalis extract and Stichopus japonicus extract showed remarkable inhibition of melanogenesis. Also, those extracts were not irritable in ocular irritation test. It is concluded from these results that Sanguisorba officinalis and Stichopus japonicus have skin whitening effect. It could be used as natural depigmental material in cosmeceutical ingredients.
Clone Cells ; Monophenol Monooxygenase ; Sanguisorba ; Skin ; Stichopus

BACKGROUND: Immunohistochemical confirmation is needed to correctly diagnose malignant melanoma, due to its heterogeneous histological appearance. OBJECTIVE: In the diagnosis of malignant melanoma, we evaluated the usefulness of recently introduced antibodies against Melan-A and tyrosinase, and compared them with antibodies against S100 protein and HMB-45. METHOD: Immunohistochemical staining with the above 4 antibodies was performed on 36 cases of malignant melanoma which had been excised. The percentage of positive tumor cells with the semi-quantitative estimation were than graded as follows; 0% = grade 0, 1-25% = grade 1, 26-50% = grade 2, 51-75% = grade 3, 76-100% = grade 4. We regarded grade 0 as negative, and grade 1 to 4 as positive. The association of Breslow thickness with the individual grade of 4 antibodies was then evaluated. RESULTS: 1. Positiveness of the 4 antibodies were as follows; 100% of the antibody against S100 protein, 97.2% of HMB-45, 97.2% of the antibody against tyrosinase, 91.7% of the antibody against Melan-A. 2. A case of a HMB-45 negative melanoma showed a grade 4 for the antibody against S100 protein, a grade 2 for the antibody against Melan-A, and a grade 3 for the antibody against tyrosinase. 3. The Breslow thickness had a significant positive correlation with the individual grade of antibody against Melan-A. CONCLUSION: In combination with the antibody against S100 protein and HMB-45, the newly developed antibodies against Melan-A and tyrosinase may be useful in the diagnosis of malignant melanoma.
Antibodies* ; Diagnosis ; MART-1 Antigen* ; Melanoma* ; Monophenol Monooxygenase*

Melanotrichoblastoma is a variant of pigmented trichoblastoma that shows highly pigmented epithelial lobules and differentiation toward the hair bulb. Histologically, the tumor presents features of trichoblastoma, and the histological findings are remarkable by virtue of the heavy melanin deposits found within and around the tumor cell nests. For the immunohistochemistry, abundant dendritic melanocytes (with the expressions of S100 protein, tyrosinase and most importantly, gp100/HMB45) are found within the tumor masses. We report here on a rare case of melanotrichoblastoma in a 57 year-old female patient.
Female ; Hair ; Humans ; Immunohistochemistry ; Melanins ; Melanocytes ; Monophenol Monooxygenase ; Virtues

Codon usage bias (CUB) is a unique property of genomes and has contributed to the better understanding of the molecular features and the evolution processes of particular gene. In this study, genetic indices associated with CUB, including relative synonymous codon usage and effective numbers of codons, as well as the nucleotide composition, were investigated in the Clonorchis sinensis tyrosinase genes and their platyhelminth orthologs, which play an important role in the eggshell formation. The relative synonymous codon usage patterns substantially differed among tyrosinase genes examined. In a neutrality analysis, the correlation between GC₁₂ and GC₃ was statistically significant, and the regression line had a relatively gradual slope (0.218). NC-plot, i.e., GC₃ vs effective number of codons (ENC), showed that most of the tyrosinase genes were below the expected curve. The codon adaptation index (CAI) values of the platyhelminth tyrosinases had a narrow distribution between 0.685/0.714 and 0.797/0.837, and were negatively correlated with their ENC. Taken together, these results suggested that CUB in the tyrosinase genes seemed to be basically governed by selection pressures rather than mutational bias, although the latter factor provided an additional force in shaping CUB of the C. sinensis and Opisthorchis viverrini genes. It was also apparent that the equilibrium point between selection pressure and mutational bias is much more inclined to selection pressure in highly expressed C. sinensis genes, than in poorly expressed genes.
Bias (Epidemiology) ; Clonorchis sinensis* ; Codon* ; Genome ; Monophenol Monooxygenase* ; Opisthorchis ; Platyhelminths

BACKGROUND: Melasma is a common acquired symmetrical hypermelanosis that occurs on sun-exposed areas, and it is frequently observed among women. Various treatment modalities have been tried, but none are completely satisfactory. 4-n-butylresorcinol, which is a resorcinol derivative that has an inhibitory effect on both tyrosinase and tyrosinase-related protein-1, was introduced in 1995 and it has received increasing attention as a new hypopigmenting agent. However, the hypopigmenting effect of 4-n-butylresorcinol in human subjects has only been shown in a few studies. OBJECTIVE: The aim of this study was to investigate the hypopigmenting efficacy and safety of 4-n-butylresorcinol 0.1% cream for the treatment of melasma. METHODS: Twenty patients with melasma were enrolled to this randomized, double-blind, vehicle-controlled, split-face comparative study. The patients were instructed to apply 4-n-butylresorcinol 0.1% cream or vehicle to each side of the face twice daily for 8 weeks. Mexameter measurements were performed along with photography at baseline, 4 weeks and 8 weeks. Adverse events were observed and recorded throughout the study. RESULTS: All the patients completed the study. Mexameter measurements demonstrated that the melanin index of the treated side showed a significant decrease when compared with that of the vehicle-treated side after 4 weeks (p=0.006) and after 8 weeks (p<0.0005). All the adverse reactions were mild and transient. CONCLUSION: 4-n-butylresorcinol 0.1% cream showed rapid efficacy and it was well tolerated when used for the treatment of melasma.
Female ; Humans ; Hyperpigmentation ; Melanins ; Melanosis ; Monophenol Monooxygenase ; Oxidoreductases ; Photography ; Resorcinols

BACKGROUND: The biosynthesis of melanin is initiated by the enzymatic oxidation of L-tyrosine to L-dopa by tyrosinase. Some precursors of melanin are cytotoxic, and melanoma cells are killed as a risk of exposare to excess tyrosine or dopa in the culture medium. However, there have been few observations of the effects of L-tyrosine on cultured normal human melanocyte. OBJECTIVE: In order to investigate whether exogenous tyrosine induces cytotoxicity in cultured normal human melanocytes as in melanoma cells, we examined the effects of L-tyrosine on proliferation and melanization in normal human melanocytes. METHODS: A melanocyte culture was produced with a modified TIC medium. L-tyrosine was added to the culture medium, 100, 200, 400, and 800uM. After 2 days of incubation, the proliferation was measured by methylthiazol tetrazolium(MTT) assay and sulforhodamine B(SRB) assay. The melanin contenis were also measured by the modified Whittaker's method. RESULTS: On MTT assay, the proliferation of melanocytes had been stirnulated significantly (p< 0.05) in all L-tyrosine added groups. On SRB assay, the proliferation of melanocytes had heen stimulated significantly (p<005) in 200, 400, 800uM of L-tyrosine added groups. The melanin contents had increased in all L-tyrosine added groups, and had increased significantly (p<0.05) in 400uM of L-tyrosine added group. CONCLUSION: L-tyrosine is not toxic to normal melanocytes, It stimulates the proliferation and melnization of cultured normal human melanocytes.
Dihydroxyphenylalanine ; Humans* ; Levodopa ; Melanins ; Melanocytes* ; Melanoma ; Monophenol Monooxygenase ; Tics ; Tyrosine*

BACKGROUND: The biosynthesis of melanin is initiated by the enzymatic oxidation of L-tyrosine to L-dopa by tyrosinase. Some precursors of melanin are cytotoxic, and melanoma cells are killed as a risk of exposare to excess tyrosine or dopa in the culture medium. However, there have been few observations of the effects of L-tyrosine on cultured normal human melanocyte. OBJECTIVE: In order to investigate whether exogenous tyrosine induces cytotoxicity in cultured normal human melanocytes as in melanoma cells, we examined the effects of L-tyrosine on proliferation and melanization in normal human melanocytes. METHODS: A melanocyte culture was produced with a modified TIC medium. L-tyrosine was added to the culture medium, 100, 200, 400, and 800uM. After 2 days of incubation, the proliferation was measured by methylthiazol tetrazolium(MTT) assay and sulforhodamine B(SRB) assay. The melanin contenis were also measured by the modified Whittaker's method. RESULTS: On MTT assay, the proliferation of melanocytes had been stirnulated significantly (p< 0.05) in all L-tyrosine added groups. On SRB assay, the proliferation of melanocytes had heen stimulated significantly (p<005) in 200, 400, 800uM of L-tyrosine added groups. The melanin contents had increased in all L-tyrosine added groups, and had increased significantly (p<0.05) in 400uM of L-tyrosine added group. CONCLUSION: L-tyrosine is not toxic to normal melanocytes, It stimulates the proliferation and melnization of cultured normal human melanocytes.
Dihydroxyphenylalanine ; Humans* ; Levodopa ; Melanins ; Melanocytes* ; Melanoma ; Monophenol Monooxygenase ; Tics ; Tyrosine*

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