Determinação da atividade antitirosinase e antioxidante de Myrsine coriacea (Sw. ) R. Br. ex Roem. & Schult. (Primulaceae) / Determination of the antityrosinase and antioxidant activity of Myrsine coriacea (Sw. ) R. Br. ex Roem. & Schult. (Primulaceae)

myrsine coriacea (Sw.) R. Br. ex Roem. & Schult. (Primulaceae) conhecida popularmente como capororoquinha ou capororoca, é amplamente distribuída nas regiões sul e sudeste do Brasil. As espécies desse gênero apresentam um potencial antioxidante e anti-inflamatório, que pode ser acessado na busca de novos ativos para o tratamento de desordens pigmentares da pele. Desta forma, este trabalho teve como objetivos avaliar o potencial antitirosinase e antioxidante de extratos e frações de M. coriacea e identificar os possíveis compostos responsáveis por essas atividades. Foram realizados ensaios para avaliar o potencial antioxidante das amostras através do método do DPPH, enquanto a capacidade hipopigmentante das amostras foi avaliado pela inibição da enzima tirosinase. Como complemento, foram determinados os teores de compostos fenólicos totais e flavonoides através dos métodos colorimétricos empregando o reagente Folin-Ciocalteau e AlCl3. Adicionalmente, os extratos de M. coriacea tiveram avaliados seus potenciais citotóxicos utilizando diferentes linhagens tumorais humanas. O perfil fitoquímico de M. coriacea foi analisado por cromatografia a gás acoplada com espectrometria de massas (CG-EM) e cromatografia em camada delgada (CCD) com padrões. Nessas análises foram identificados 34 compostos, sendo o ácido palmítico e o palmitato de etila os compostos majoritários nas amostras de M. coriacea. O extrato bruto das folhas apresentou o maior teor de fenólicos totais, enquanto a fração de acetato de etila das folhas teve o maior teor de flavonoides. Contudo, o extrato bruto dos frutos apresentou a melhor atividade antioxidante de todas as amostras analisadas, apresentando também a melhor atividade antitirosinase. Dentre os compostos anotados, mandenol, ácido -linoleico e o linolenato de etila foram os compostos considerados como possíveis inibidores da tirosinase, com boa interação molecular com a enzima nas análises de ancoragem molecular in silico. Das amostras analisadas com relação a inibição de crescimento frente as células tumorais, a amostra da fração de clorofórmio das folhas foi a que apresentou potencial antitumoral frente as células de adenocarcinoma de cólon (HCT116)

myrsine coriacea (Sw.) R. Br. ex Roem. & Schult. (Primulaceae) popularly known as capororoquinha or capororoca, is widely distributed in southern and southeastern Brazil. Myrsine species have an antioxidant and anti-inflammatory potential, which can be accessed in the search for new actives for the treatment of skin pigmentation disorders. Thus, this work aimed to evaluate the antityrosinase and antioxidant potential from extracts and fractions of M. coriacea and to identify the probable compounds responsible for these activities. Assays were performed to evaluate the antioxidant potential of the samples using the DPPH method, while the hypopigmentation capacity of the samples was evaluated by the tyrosinase inhibition. As a complement, the amounts of total phenolic compounds and flavonoids were determined through colorimetric methods using the Folin-Ciocalteau reagent and AlCl3. Additionally, M. coriacea extracts had their cytotoxic potential evaluated using different human tumor cell lines. M. coriacea phytochemical profile was obtained by gas chromatography coupled with mass spectrometry (GC-MS) and thin layer chromatography (TLC) with standards. In these analyses, 34 compounds were identified, with palmitic acid and ethyl palmitate as the major compounds in M. coriacea samples. The leaf crude extract presented the highest total phenolics contents, while the leaf ethyl acetate fraction had the highest flavonoid amounts. However, the fruit crude extract showed the best antioxidant and antityrosinase activities of all analyzed samples. Among the annotated compounds, mandenol, -linoleic acid and ethyl linolenate were the compounds considered as putative tyrosinase inhibitors, presenting good molecular interaction with the enzyme active site in the in silico molecular docking analysis. The leaf chloroform fraction was the only sample that showed an antitumor potential against colon adenocarcinoma cells (HCT116)

Anti-tyrosinase, anti-skin pathogenic bacterial, and antioxidant activities and phytochemical constituents of Dracaena cochinchinensis (Lour.) S.C. Chen extract

Dracaena cochinchinensis (Lour.) S.C. Chen (Chandaeng) is an important traditional medicinal plant used in ancient Thai household remedies. This research focused on investigating the biological properties, including the antibacterial, anti-tyrosinase, antioxidant activities, and phytochemical characteristics of crude Chandaeng extracts. Dried Chandaeng heartwood powder was extracted using ethanol, methanol, and deionized water. The antibacterial activities of the extracts were then tested against skin pathogens, including Cutibacterium acnes (DMST14916), Staphylococcus epidermidis (TISTR518), and Staphylococcus aureus (TISTR321). The ethanolic extract showed antibacterial activity. In a time-kill assay, all bacteria were completely killed after being exposed to it, while the cell membranes were found to have leaked when viewed under a scanning electron microscope. Antioxidant potential was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2¢-azino-bis -3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. According to the findings, the crude ethanolic extract of Chandaeng showed the highest level of antioxidant activity. Furthermore, the potential of the extract to treat skin hyperpigmentation by inhibiting tyrosinase, an important melanin synthesis enzyme, was determined and the ethanolic extract was found to be an anti-tyrosinase agent. Finally, the crude ethanolic extract showed the highest total phenolic compound and flavonoid content. In conclusion, crude Chandaeng extract showed significant potential in activity against skin pathogenic bacteria, antioxidant activity, and tyrosinase inhibition. These properties of the extract could be applied to skincare cosmetics.

Physicochemical characterization and cosmetic applications of Passiflora nitida Kunth leaf extract

Abstract Passiflora nitida Kunth, an Amazonian Passiflora species, is little studied, although the specie's high biological potential. Herein the plant's pharmacognostic characterization, extract production, antioxidant potential evaluation, and application of this extract in cosmetic products is reported. The physical chemical parameters analyzed were particle size by sieve analysis, loss through drying, extractive yield, total ash content, laser granulometry, specific surface area and pore diameter (SBET), differential scanning calorimetry, thermogravimetry (TG), and wave dispersive X-Ray fluorescence (WDXRF). Total phenol/flavonoid content, LC-MS/MS analysis, DPPH and ABTS antioxidant radical assays, cytotoxicity, melanin, and tyrosinase inhibition in melanocytes test provided evidence to determine the content of the major constituent. P. nitida dry extract provided a fine powder with mesopores determined by SBET, with the TG curve showing five stages of mass loss. The antioxidant potential ranged between 23.5-31.5 mg∙mL-1 and tyrosinase inhibition between 400-654 µg∙mL-1. The species presented an antimelanogenic effect and an inhibitory activity of cellular tyrosinase (26.6%) at 25 µg/mL. The LC-MS/MS analysis of the spray-dried extract displayed the main and minor phenolic compounds constituting this sample. The results indicate that P. nitida extract has promising features for the development of cosmetic formulations

Composição química e atividades biológicas de extratos e frações de Guadua chacoensis (Rojas) Londoño & P.M. Peterson / Chemical composition and biological activities of extracts and fractions of Guadua chacoensis (Rojas) Londoño & P.M. Peterson

O Brasil é o país que possui a maior diversidade de bambus em todo o continente americano, com mais de 200 espécies catalogadas. Devido à alta resistência e durabilidade, essas espécies são muito utilizadas na construção civil e confecção de móveis e utensílios. No entanto, faltam estudos que investiguem a composição química e as atividades biológicas. Neste projeto foram avaliados extratos etanólicos de folhas e colmos de Guadua chacoensis (Rojas) Londoño & P.M. Peterson e frações em hexano, clorofórmio, acetato de etila e n-butanol. Também se obteve o óleo volátil, mas com um rendimento extremamente baixo (0,00079%). As frações dos extratos apresentaram teores de compostos fenólicos variando entre 1,92 e 15,80 µg EAG/mg. Esses compostos mostraram-se mais abundantes nas amostras de colmos. Em relação ao teor de flavonoides, as folhas apresentaram maior quantidade, variando entre 0,39 e 1,18 µg EQ/mg contra 0,17 a 0,34 µg EQ/mg nos colmos. Investigou-se a atividade antimicrobiana dos extratos, frações e óleo volátil frente cinco microrganismos: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans e Aspergillus brasiliensis. As amostras demonstraram potencial inibitório moderado a bom contra S. aureus e C. albicans, porém fraca para as demais espécies. Testou-se a capacidade antioxidante frente o radical DPPH e os resultados indicaram atividade antioxidante significativa, especialmente as frações acetato e butanol de colmos. As folhas apresentaram EC50 variando entre 67,5 e 124,0 µg/mL e os colmos entre 40,2 e 124 µg/mL. A inibição da enzima tirosinase, que está associada à produção de melanina, também se mostrou boa a uma concentração de 1 mg/mL, com o extrato bruto de colmos apresentando 43% de inibição, seguido pelas frações acetato (36%) e n-butanol (38%) de folhas. As análises por CG-MS detectaram pelo menos 44 compostos diferentes no óleo volátil, com vários terpenos e sesquiterpenos, e com ß-ionona sendo o componente majoritário (8,75%). As amostras de colmos e folhas apontaram grande diversidade de compostos, cerca de 20 para cada fração, onde os ácidos graxos como ácido palmítico e linoleico e seus ésteres derivados foram os mais abundantes. A análise dos perfis cromatográficos por CCD e CLAE revelaram a presença de ácido p-cumárico nos colmos de G. chacoensis. Esse composto tem relevante atividade antioxidante e de inibição da tirosinase. Também foi possível identificar a quercetagetina-7-O-glicosídeo, uma flavona glicosilada, com propriedades anti-inflamatorias e antidiabéticas. Desta forma, constatou-se que G. chacoensis apresenta grande diversidade de metabólitos secundários com atividades biológicas relevantes, como atividade antioxidante e clareadora, abrindo caminho para investigações mais profundas de suas aplicações, especialmente no segmento de cosméticos e produtos naturais

Brazil is the country with the greatest diversity of bamboo in the entire American continent, with more than 200 species catalogued. Due to their high resistance and durability, they are widely used in home construction and manufacture of furniture and utensils. However, studies investigating chemical composition and biological activities are absent. In this project, ethanol extracts from leaves and stems of Guadua chacoensis (Rojas) Londoño & P.M. Peterson and fractions in hexane, chloroform, ethyl acetate and n-butanol were evaluated. Volatile oil was also obtained, but with an extremely low yield (0.00079%). The fractions of the extracts presented contents of phenolic compounds varying between 1.92 and 15.80 µg GAE/mg. These compounds were more abundant in culm samples. In relation to the flavonoid content, leaves showed a greater amount, varying between 0.39 and 1.18 µg QE/mg against 0.17 to 0.34 µg QE/mg in culms. The antimicrobial activity of extracts, fractions and volatile oil were investigated against five microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis. The samples showed moderate to good inhibitory potential against S. aureus and C. albicans, but weak for the other species. The antioxidant capacity was tested against the DPPH radical and the results indicated significant antioxidant activity, especially acetate and butanol culm fractions. The leaves presented EC50 varying between 67.5 and 124.0 µg/mL and culms between 40.2 and 124 µg/mL. The inhibition of the enzyme tyrosinase, which is associated with the production of melanin, was also shown to be good at a concentration of 1 mg/mL, with the raw culm extract showing 43% inhibition, followed by acetate (36%) and n-butanol (38%) fractions of leaves. CG-MS analysis detected at least 44 different compounds in volatile oil, with several terpenes and sesquiterpenes, and with ß-ionone being the major component (8.75%). Culm and leaf samples showed great diversity of compounds, about 20 for each fraction, where fatty acids such as palmitic and linoleic acid and their derivative esters were the most abundant. The analysis of the chromatographic profiles by TLC and HPLC revealed the presence of p-coumaric acid in culms of G. chacoensis. This compound has relevant antioxidant and tyrosinase inhibiting activity. It was also possible to identify quercetagetine-7-O-glucoside, a glycosylated flavone, with anti-inflammatory and anti-diabetic properties. Thus, it was found that G. chacoensis presents a great diversity of secondary metabolites with relevant biological activities, such as antioxidant and whitening activity, opening ways for deeper investigations of its applications, especially in the segment of cosmetics and natural products

Genetic testing and prenatal diagnosis for thirteen Chinese pedigrees affected with oculocutaneous albinism / 中华医学遗传学杂志

OBJECTIVE@#To identify the causative variants in 13 Chinese pedigrees affected with oculocutaneous albinism (OCA) so as to provide genetic counseling and prenatal diagnosis to them.@*METHODS@#Thirteen unrelated pedigrees with clinically diagnosed OCA were collected and classified based on the manifestation of skin and eyes. With informed consent obtained from the participants, peripheral blood samples were collected from the probands and their family members for the extraction of genomic DNA. Candidate variants were screened by targeted capture and next generation sequencing, and the results were validated by Sanger sequencing. Prenatal diagnosis was provided to the families upon their subsequent pregnancies.@*RESULTS@#Causative variants were detected in all probands, including 10 with compound heterozygotes or homozygotes for TYR gene variants and 3 with compound heterozygotes for OCA2 gene variants. Among these, two variants [TYR: c.650G>C (p.Arg217Pro) and OCA2: c.516-2A>T] were unreported previously. The pathogenicity of the novel TYR: c.650G>C (p.Arg217Pro) variant was verified through bioinformatic analysis and prediction of three dimensional structure of the protein. Prenatal diagnosis was provided to 6 fetuses with a high risk for OCA. Four fetuses were found to be carriers, one did not carry the variants of the proband, and one was affected with OCA.@*CONCLUSION@#Identification of the pathogenic variants in the 13 probands, including 2 novel ones, has expanded the mutational spectrum of OCA and enabled genetic counseling and prenatal diagnosis for the families.

Biological properties and phytochemical characterization from Miconia chamissois Naudin aqueous extract / Propiedades biológicas y caracterización fitoquímica del extracto acuoso de Miconia chamissois Naudin

The objective of this study was to evaluate biological and phytochemical properties of the aqueous extract from the leaves of Miconia chamissois Naudin (AEMC). Phytochemical properties were assessed by analyzing the chromatographic profile and the polyphenol content of AEMC. Biological properties evaluation was conducted based on cytotoxicity assay and by evaluating the antioxidant, antimicrobial, and enzymatic inhibition activities. Results indicated the presence of phytochemicals in AEMC such as flavonoids and polyphenols, including rutin, isoquercitrin and vitexin derivatives. AEMC showed antioxidant activity, which may be attributed to the high polyphenolic content. Moreover, AEMC demonstrated in vitro enzyme inhibition activity against tyrosinase and alpha-amylase, as well as showed low cytotoxicity. On the other hand, AEMC exhibited weak antimicrobial activity against S. aureusand C. albicans. Thus, AEMC is a promising alternative in search of potential drugs for the treatment of diseases induced by oxidative stress and inflammation, conditions due to hyperpigmentation processes, such as melisma, as well as for diabetes.

El objetivo de este estudio fue detectar las propiedades biológicas y fitoquímicos del extracto acuoso de las hojas de Miconia chamissois Naudin (AEMC). Las propiedades fitoquímicas se evaluaron analizando el perfil cromatográfico y el contenido de polifenoles de AEMC. La evaluación de las propiedades biológicas se realizó en base al ensayo de citotoxicidad y evaluando las actividades de inhibición antioxidante, antimicrobiana y enzimática. Los resultados indicaron la presencia de fitoquímicos en AEMC, como flavonoides y polifenoles, que incluyen derivados de rutina, isoquercitrina y vitexina. AEMC mostró una actividad antioxidante considerable, que puede atribuirse al alto contenido polifenólico. Además, AEMC exhibió actividad de inhibición enzimática in vitro contra tirosinasa y alfa-amilasa, así como mostró baja citotoxicidad. Por otro lado, AEMC demostró actividad antimicrobiana débil contra S. aureusy C. albicans. Por lo tanto, AEMC es una alternativa prometedora en busca de posibles drogas para el tratamiento de enfermedades inducidas por el estrés oxidativo y la inflamación, afecciones debidas a procesos de hiperpigmentación, como el melasma, así como para la diabetes.

Rapid discovery of tyrosinase inhibitors from Sophora flavescens:significance for comprehensive utilization of its non-medicinal resources / 中国中药杂志

Sophorae Flavescentis Radix,derived from the root of Sophora flavescens in the Leguminosae family,has been widely used in the medicine,agriculture,animal husbandry,and daily chemical industry. A pharmacophore model-based method for rapid discovery of tyrosinase inhibitors( TIs) from S. flavescens was established by molecular docking under Lipinski rules,and verified by enzyme assays. Briefly,the chemical constituent database of S. flavescens( CDSF) was established based on the previous papers. Theoptimal pharmacophore model( OPM) was constructed by DS 2019 on the basis of known active TIs. Eighty-three hits predominated by flavonoids having higher fitting scores with OPM than the positive control were screened out,and subjected to molecular docking based on the three-dimensional structure of tyrosinase crystal protein. The potential TIs such as kurarinone and nor-kurarinone were rapidly discovered from the compounds with higher docking scores than the positive control under the Lipinski rules. The results were verified by the in vitro enzyme assays. The inhibition activities of tyrosinase from non-medicinal parts of S. flavescens were also tested to explore the relationship between the inhibition activity and chemical compositions. This study is expected to provide data support for the comprehensive application and development of S. flavescens and also a new method for the rapid discovery of active substances or functional constituents in the complex systems.

Leucismo em jacaretinga: relato de caso / Leucism in jacaretinga: case report

Dentre os crocodilianos com ocorrência no Brasil, o Caiman crocodilus (Linnaeus, 1758) é a espécie de maior frequência, porém sua presença em estudos científicos restringe-se a levantamentos faunísticos, na maioria das vezes. O leucismo, também conhecido como albinismo parcial, é uma anomalia cromática ainda pouco conhecida. Indivíduos portadores dos genes que condicionam a doença apresentam ausência de pigmentação em uma parte ou em todo o corpo, porém os olhos não apresentam alteração. O objetivo deste trabalho foi realizar o primeiro registro de Caiman crocodilus com leucismo no mundo.(AU)

Among crocodilians in Brazil, Caiman crocodilus (Linnaeus, 1758) is the most frequent species, but its presence in scientific studies is mostly restricted to faunal surveys. Leukism, also known as partial albinism, is a still little known chromatic anomaly. Individuals with genes that condition the disease present no pigmentation in one part or in the whole body, but the eyes did not change. The objective of this work was to perform the first record of Caiman crocodilus with leucismo in the world.(AU)

Phenolic profile and antioxidant, acetylcholinesterase, and tyrosinase inhibitor activities of Jurinea tzar-ferdinandii Davidov, an endemic plant of the Balkans / Perfil fenólico y actividad antioxidante, acetilcolinesterasa e inhibidora de tirosinasa de Jurinea tzar-ferdinandii Davidov, planta endémica de los Balcanes

The methanol extract of the Balkan endemic species Jurinea tzar-ferdinandii Davidov demonstrated weak antioxidant activity against DPPH• and ABTS+• and low inhibitory potential against acetylcholinesterase (8.3% Inh.) and tyrosinase (IC50 = 208 ± 8 µg/mL) enzymes. Phytochemical investigation of the extract led to isolation and identification of apigenin, luteolin, apigenin-7-O-glucoside, apigenin-4'-O-glucoside, apigenin-7-O-gentiobioside, luteolin-4'-O-glucoside, rutin, narcissin, chlorogenic and 1,5-dicaffeoylquinic acid. With exception of apigenin and rutin, all isolated compounds are reported for the first time in the representatives of genus Jurinea. The distribution of flavonoids was discussed from chemotaxonomic point of view.

El extracto de metanol de la especie endémica de los Balcanes Jurinea tzar-ferdinandii Davidov demostró una actividad antioxidante débil contra DPPH• y ABTS+• y un bajo potencial inhibidor contra las enzimas acetilcolinesterasa (8.3% Inh.) tirosinasa (IC50 = 208 ± 8 µg/mL). La investigación fitoquímica del extracto condujo al aislamiento e identificación de apigenina, luteolina, apigenina-7-Oglucósido, apigenina-4'-O-glucósido, apigenina-7-O-gentiobiósido, luteolina-4'-O-glucósido, rutina, narcissin, clorogénico y ácido 1,5- dicafeoilquinico. Con excepción de la apigenina y la rutina, todos los compuestos aislados se informan por primera vez en el género Jurinea. La distribución de flavonoides se discute desde el punto de vista quimiotaxonómico.

Ocotea (Lauraceae) Amazonian essential oils chemical composition and their tyrosinase inhibition to use in cosmetics / Ocotea (Lauraceae) composición química de aceites esenciales amazónicos y su inhibición de la tirosinasa para usar en cosméticos

This study presents analyses on the chemistry, biology, pharmacology and chromatography of essential oils extracted from three species of the Ocotea genus: O. minor, O. ceanothifolia and O. leucoxylon. Leaves and stems, as well as the bark of O. minor, were processed using a modified Clevenger apparatus. Seven essential oils were obtained and analyzed using GC-FID and GC-MS, and their chemical compositions were determined. Assays of cytotoxicity, antioxidant and free radical scavenging activity, as well as tyrosinase and elastase inhibition were performed. In total, 25 constituents were identified, the principal being sesquiterpenes, such as spathulenol caryophyllene and its oxide. The oils did not present cytotoxicity using a hemolytic model, but also did not show antioxidant activity in the DPPH assay. Essential oil from stems of O. ceanothifolia, rich in spathulenol and caryophyllene oxide, demonstrated the capacity to inhibit 49.08% of tyrosinase activity at a concentration of 100 µg/mL. This research contributes to the chemical profile analysis of the three species of Ocoteathrough chemical investigations and biological activity, which are reported for the first time here in this study.

Este trabajo realiza un estudio químico, biológico, farmacológico y cromatográfico de aceites esenciales extraídos de tres especies del género Ocotea: O. minor, O. ceanothifoliay O. leucoxylon. Las hojas y tallos, así como la corteza de O. minor, se procesaron utilizando un aparato Clevenger modificado. Se obtuvieron siete aceites esenciales y se analizaron usando GC-FID y GC-MS, y se determinaron sus composiciones químicas. Se realizaron ensayos de citotoxicidad, actividad antioxidante y de atrapamiento de radicales libres, así como inhibición de tirosinasa y elastasa. En total, se identificaron 25 componentes, siendo los principales sesquiterpenos, como el spathulenol cariofileno y su óxido. Los aceites no presentaron citotoxicidad en un modelo hemolítico y tampoco mostraron actividad antioxidante en el ensayo con DPPH. El aceite esencial de tallos de O. ceanothifolia, rico en espatulenol y óxido de cariofileno, mostró capacidad para inhibir el 49.08% de la actividad de tirosinasa a una concentración de 100 µg/mL. Esta investigación contribuye al análisis del perfil químico de las tres especies de Ocotea a través de investigaciones químicas y actividad biológica la cual se informan por primera vez.

Phenolic compounds profile, neuroprotective effect and antioxidant potential of a commercial Turkish coffee / Perfil do componente fenólico, efeito neuroprotector e potencial antioxidante de um café comercial turco

ABSTRACT Objective The purpose of this study is to determine the phenolic and flavonoid contents, and antioxidant activities and neuroprotective effects of powdered coffee sample of a commercial coffee brand originated from Sivas, Turkey. Methods Total phenolic, flavonoid and antioxidant contents, enzymatic and non-enzymatic antioxidative activities based on 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity, metal chelating potential, reducing power, superoxide dismutase and catalase activity tests and lipid peroxidation inhibition potentials of the ethanolic and aqueous extracts of the coffee sample were assayed using the commonly preferred spectrophotometric methods. Furthermore the extracts' cholinesterase and tyrosinase inhibition potentials were evaluated. Phenolic profiles of the coffee sample were investigated using high performance liquid chromatography. Results Catechin was the most frequently detected phenolic acid. In addition, it was demonstrated that the water extract has a significant impact when compared with standard antioxidants. While the SC50 (sufficient concentration to obtain 50% of a maximum scavenging capacity) value for the scavenging activity of 2,2-diphenyl-1-picrylhydrazyl free radical was calculated as being 0.08mg/mL for water extract, the amount of chelating agents with half Fe2+ ions in the medium was found to be 0.271mg/mL. Additionally, it was shown that 0.1mg/mL concentration of both extracts prevents lipid peroxidation by 8%. Compared with standard drugs, inhibition potentials of cholinesterase and tyrosinase enzymes were considered as moderately acceptable in these samples. Conclusion Besides the extracts' enzymatic antioxidant activity, their inhibition potential on cholinesterase and tyrosinase enzymes - which are important clinical enzymes - reveal that this natural source can be used as a valuable resource in different fields, especially in medicine.

RESUMO Objetivo O objetivo deste estudo é determinar o conteúdo fenólico e flavonoide, bem como as atividades antioxidantes e os efeitos neuroprotetores de uma amostra de café em pó de uma promissora marca comercial proveniente de Sivas, Turquia. Métodos A partir dos métodos espectrofotométricos comumente utilizados, foram analisados os seguintes aspectos da amostra de café: teores de fenólicos totais, flavonoides e antioxidantes; atividades antioxidantes enzimáticas e não enzimáticas, baseadas na atividade de eliminação de radicais livres de 2,2-difenil-1-picrilhidrazila potencial quelante de metais; poder redutor; testes de atividade de superóxido dismutase e catalase; e potenciais de inibição da peroxidação lipídica dos extratos etanólicos e aquosos. Além disso, foram avaliados os potenciais de inibição da colinesterase e da tirosinase dos extratos. Os perfis fenólicos da amostra de café foram investigados por cromatografia líquida de alta eficiência. Resultados Entre os ácidos fenólicos estudados, o mais detectado foi a catequina. Especialmente, foi demonstrado que o extrato de água tem um impacto significativo quando comparado com os antioxidantes padrão. Determinou--se que o valor de SC50 (a concentração suficiente para obter 50% da capacidade máxima de eliminação) da atividade de eliminação do radical 2,2-difenil-1-picrilhidrazilab/para extrato de água era de 0,08mg/mL, enquanto a quantidade de agentes quelantes com metade de Fe2+ íons na média foi encontrada como 0,271mg/mL. Também foi demonstrado que a concentração de 0,1mg/mL de ambos os extratos inibe a peroxidação lipídica em cerca de 8%. Comparado com drogas padrão, os potenciais de inibição das amostras nas enzimas e tirosinase foram aceitáveis como moderados. Conclusão Os resultados mostram que, além de terem atividade antioxidante enzimática, os extratos apresentam potencial de inibição das enzimas colinesterase e tirosinase, que são importantes enzimas clínicas, o que revela que essa fonte natural pode ser usada como um recurso valioso em vários campos, principalmente na medicina.

Chronic stress induces fur color change from dark to brown by decreasing follicle melanocytes and tyrosinase activity in female C57BL/6 mice / 生理学报

Increasing evidence suggests that stress may induce changes in hair color, with the underlying mechanism incompletely understood. In this study, female C57BL/6 mice subjected to electric foot shock combined with restraint stress were used to build chronic stress mouse model. The melanin contents and tyrosinase activity were measured in mouse skin and B16F10 melanoma cells. The enzyme-linked immunosorbent assay (ELISA) was used to determine the content of tumor necrosis factor α (TNF-α), interleukin- 1β (IL-1β) and interleukin-6 (IL-6) in the mouse skin. The content of nuclear factor κB (NFκB)/p65 subunit in mouse skins was valued by immunofluorescence staining. The results demonstrated that under chronic stress, the fur color turned from dark to brown in C57BL/6 mice due to the decrease of follicle melanocytes and tyrosinase activity in C57BL/6 mouse skin. Simultaneously, inflammatory responses in skins were detected as shown by increased NFκB activity and TNF-α expression in stressed mouse skin. In cultured B16F10 melanoma cells, TNF-α reduced the melanogenesis and tyrosinase activity in a dose-dependent manner. These findings indicate that chronic stress induces fur color change by decreasing follicle melanocytes and tyrosinase activity in female C57BL/6 mice, and TNF-α may play an important role in stress-induced hair color change.

Melanin synthesis and regulation in vivo and commonly used melanin inhibitors from natural products and traditional Chinese medicine / 中国中药杂志

Melanin is an important factor affecting human skin color. This study defines its synthetic pathways and regulatory pathways have the practical significance for the treatment of diseases caused by pigmentation problems, such as chloasma. Besides, it also provides a theoretical basis for screening out melanin inhibitors and developing whitening and freckle products. At present, the melanin inhibitors used in whitening and freckle products mainly come from natural products and traditional Chinese medicine. This article first introduces the melanin biosynthesis pathway with tyrosinase as the core, defines the synthesis, transport and catalytic activity of tyrosinase as the three key factors affecting melanin synthesis, and then reviews two common types of melanin inhibitors, namely tyrosinase synthesis inhibitors and tyrosinase inhibitors derived from natural products and traditional Chinese medicine. This article provides guidance for the development of new melanin inhibitors, and puts forward the idea for combining and synergizing inhibitors according to different mechanisms, in order to develop new whitening formulas.

Anti-melanogenic effects of Hordeum vulgare L. barely sprout extract in murine B16F10 melanoma cells / 한국영양학회지

PURPOSE: Barely sprout is a well-known oriental herbal medicine with a wide range of health benefits. Recent studies have provided scientific evidence of its therapeutic effects with expanded application. This study investigated anti-melanogenic effect of barley sprout water extract (BSE) in murine melanocyte B16F10. METHODS: Various concentrations (0, 50, 125, and 250 µg/mL) of BSE and arbutin (150 ppm) were applied to B16F10 stimulated with or without alpha-melanocyte stimulating hormone (100 nM) for 72 hours. The whitening potency of BSE was determined altered cellular melanin contents. Activity and expression of tyrosinase and microphthalmia-associated transcription factor (MITF) were also assayed. RESULTS: Experimental results revealed that treatment with BSE reduced cellular melanin production by approximately 40% compared to the control. Molecular findings supported that suppressed activity and expression of tyrosinase and MITF proteins by BSE were associated with declined cellular melanogenesis. Furthermore, anti-melanogenic effect of BSE (250 µg/mL) was similar to that of arbutin, a commonly used whitening agent. Lastly, polyphenols including p-coumaric, ferulic, and vanillic acids were identified in BSE using HPLC analyses. They might be potential active ingredients showing such melanogenesis-reducing effect. CONCLUSION: BSE was evident to possess favorable anti-melanogenic potency in an in vitro model. As a natural food sourced material, BSE could be an effective depigmentation agent with potential application in pharmaceutical and cosmetic industries.

The Anti-melanogenesis Activities of Some Selected Brown Macroalgae from Northern Coasts of the Persian Gulf

Abstract Melanogenesis is a biological process which led to the synthesis of melanin pigment. Abnormal melanin production results in melasma, solar lentigo, post inflammatory melanoderma, etc. In this study, we examined the potential inhibitory effects of 17 brown macroalgae from Persian Gulf on melanogenesis. The effects of various concentrations (100, 250 and 500 µg/mL) of methanolic extracts of macroalgae belonging to four genera (including: Padina, Colpomonia, Cystoseira and Sargassum) were studied on oxidation of L-Dopa by mushroom tyrosinase. Subsequently, the activity of macroalgae with high inhibitory effect on monophenolase activity of mushroom tyrosinase and zebrafish was investigated using L-tyrosine as a substrate. Anti-melanogenesis effects of algae extracts were studied on zebrafish as an alternative in vivo model. Kojic acid was used as a positive control. All the tested macroalgae showed inhibitory effect on activities of diphenolase and monophenolase (of mushroom tyrosinase). P. boergesinii exhibited the most in vivo anti-tyrosinase activity compared with other samples. P. boergesenii inhibited zebrafish tyrosinase more potent than kojic acid (83% vs 50% inhibition for kojic acid). Moreover, it reduced melanin synthesis in zebrafish 42% (kojic acid: 50%).

Anti-Melanogenic Effect from Submerged Mycelial Cultures of Ganoderma weberianum

Compounds from Lingzhi has been demonstrated the ability for inhibiting tyrosinase (a key enzyme in melanogenesis) activity. In this study, we investigated the anti-melanogenic activity from the submerged mycelial culture of Ganoderma weberianum and elucidated the skin lightening mechanism by B16-F10 murine melanoma cells. From the cellular context, several fractionated mycelium samples exhibited anti-melanogenic activity by reducing more than 40% extracellular melanin content of B16-F10 melanoma cells. In particular, the fractionated chloroform extract (CF-F3) inhibited both secreted and intracellular melanin with the lowest dosage (25 ppm). Further analysis demonstrated that CF-F3 inhibited cellular tyrosinase activity without altering its protein expression. Taken together, our study has demonstrated that the chemical extracts from submerged mycelial culture of G. weberianum have the potential to serve as an alternative anti-melanogenic agent.

Primary Malignant Melanoma of the Breast: A Report of Two Cases

Primary malignant melanoma of the breast (PMMB) is a rare tumor with only a few case reports available in the literature. We report two cases of PMMB, one derived from the breast parenchyma and the other from the breast skin. The first case consisted of atypical epithelioid cells without overt melanocytic differentiation like melanin pigments. The tumor cells showed diffuse positivity for S100 protein, tyrosinase, and BRAF V600E. However, the tumor cells were negative for cytokeratin, epithelial membrane antigen, and HMB-45. The second case showed atypical melanocytic proliferation with heavy melanin pigmentation. The tumor cells were positive for S100 protein, HMB-45, tyrosinase, and BRAF V600E. These two cases represent two distinct presentations of PMMB in terms of skin involvement, melanin pigmentation, and HMB-45 positivity. Although PMMB is very rare, the possibility of this entity should be considered in malignant epithelioid neoplasms in the breast parenchyma.

Synthesis of transdermal aloesin loaded zinc oxide nanoparticles and its inhibitory effect on the activity of tyrosinase / 生物医学工程学杂志

Zinc oxide quantum dots (ZnO QDs) were synthesized by gel-sol method and employed as the transdermal aloesin (Alo) carriers. ZnO QDs were surface-functionalized with amino using aminopropyltriethoxysilane (APTES). Alo was covalently bonded on the surface of ZnO QDs via N,N'-carbonyldiimidazole to obtain Alo NPs, which were characterized by transmission electron microscope (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR) and thermal gravimetric analyzer (TGA). TEM images showed that ZnO QDs were analogously sphere and monodisperse with a reasonably narrow size distribution, of which was around 4 nm. The size of Alo NPs increased to around 8 nm due to the surface modification. The intense bands at around 3 400 cm and 1 200 cm in the FTIR spectrum of Alo NPs from the vibration of -OH indicated the linkage of Alo on the surface of ZnO QDs. The results of TGA analysis showed that the mass ratio of ZnO QDs and Alo were 39.27% and 35.14%, respectively. The penetration of Alo NPs was much higher than raw Alo according to the passive penetration experiments with Franz-type diffusion cells instrument using full-thickness cavy skin, which manifested the improvement of the penetration for Alo delivered by ZnO QDs. The pH-controlled drug release behavior was investigated. At pH 7.4, only a small amount of Alo (1.45% ± 0.21%) had been released after 2 h. In contrast, as incubation at pH 5.0 of which pH was similar to endosomal environment, Alo was released very fast (87.63% ± 0.46% in 2 h) from Alo NPs, confirming that Alo NPs could response to the pH and realize the intracellular drug release. The inhibitory effect of Alo NPs on tyrosinase was in a dose dependent manner. When the concentration of Alo NPs was 12.5 μg/mL, the inhibition rate was up to 40.32% ± 1.57%. All the results show that the Alo NPs hold a great potential in transdermal tyrosinase inhibition.

Mutation analysis of two pedigrees with suspected oculocutaneous albinism / 中华医学遗传学杂志

OBJECTIVE@#To analyze the clinical presentation and gene of 2 pedigrees with suspected oculocutaneous albinism(OCA), and provide basis for clinical classification, genetic counseling and prenatal diagnosis.@*METHODS@#Variants were identified using next-generation sequencing(NGS) and confirmed by Sanger sequencing in 2 pedigrees with suspected OCA. The pathogenicity of the variants was analyzed according to the American College of Medical Genetics and Genomics (ACMG) standard.@*RESULTS@#Two compound heterozygous mutations of TYR and OCA2 genes were identified respectively in 2 pedigrees with suspected OCA. The mutation of c.819+3insATATGCC in TYR and the mutation of c.1870G>C in OCA2 are first reported in this study. The pathogenicity analysis shows that two novel mutations are likely pathogenic by combination of prediction of SIFT, Polyphen-2 and Human Splicing Finder.@*CONCLUSION@#The findings of this study expand the mutational spectrum of OCA. Compound heterozygous mutations in the TYR and OCA2 gene may be responsible for clinical manifestations of 2 pedigrees with suspected OCA.

Anti-melanogenesis and Anti-inflammatory Effects of Cinnamomi Cortex Extract In Vitro / 대한피부과학회지

BACKGROUND: Many researchers have sought to identify safe, natural herbal extracts that exert an anti-melanogenesis effect. Cinnamomi cortex has been widely used as a herbal medicine in Asia and Europe. OBJECTIVE: To confirm the inhibitory effects of Cinnamomi cortex extract against melanogenesis and inflammation and to elucidate the underlying mechanism of these actions. METHODS: Effects of Cinnamomi cortex extract on melanin synthesis and tyrosinase activity in B16F10 melanoma cells were evaluated using an ELISA reader. Tyrosinase and MITF protein expression was determined using western blotting. Nitric oxide production in RAW 264.7 cells was measured using Griess reaction. PGE₂ was assayed with an ELISA kit. RESULTS: Cinnamomi cortex extracts inhibited melanin synthesis, tyrosinase activity, and MITF and tyrosinase expression through regulation of the ERK and CREB genes in α-MSH-induced B16 melanoma cells. In addition, Cinnamomi cortex extracts inhibited the expression of NO, PGE₂, and pro-inflammatory cytokines in lipopolysaccharide-induced RAW 264.7 cells. CONCLUSION: We suggest that Cinnamomi cortex may be a potentially useful agent for treating inflammatory skin diseases such as hyperpigmentation based on its inhibitory effects against melanin synthesis and inflammation response in vitro.