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1.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361729

RESUMO

Tyrosinase (TYR) is a type III copper oxidase present in fungi, plants and animals. The inhibitor of human TYR plays a vital role in pharmaceutical and cosmetic fields by preventing synthesis of melanin in the skin. To search for an effective TYR inhibitor from various plant extracts, a kinetic study of TYR inhibition was performed with mushroom TYR. Among Panax ginseng, Alpinia galanga, Vitis vinifera and Moringa oleifera, the extracts of V. vinifera seed, A. galanga rhizome and M. oleifera leaf reversibly inhibited TYR diphenolase activity with IC50 values of 94.8 ± 0.2 µg/mL, 105.4 ± 0.2 µg/mL and 121.3 ± 0.4 µg/mL, respectively. Under the same conditions, the IC50 values of the representative TYR inhibitors of ascorbic acid and kojic acid were found at 235.7 ± 1.0 and 192.3 ± 0.4 µg/mL, respectively. An inhibition kinetics study demonstrated mixed-type inhibition of TYR diphenolase by A. galanga and V. vinifera, whereas a rare uncompetitive inhibition pattern was found from M. oleifera with an inhibition constant of Kii 73 µg/mL. Phytochemical investigation by HPLC-MS proposed luteolin as a specific TYR diphenolase ES complex inhibitor, which was confirmed by the inhibition kinetics of luteolin. The results clearly showed that studying TYR inhibition kinetics with plant extract mixtures can be utilized for the screening of specific TYR inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Luteolina/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Moringa oleifera/química , Agaricales/química , Agaricales/enzimologia , Alpinia/química , Ácido Ascórbico/química , Ácido Ascórbico/isolamento & purificação , Ácido Ascórbico/farmacologia , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Proteínas Fúngicas/isolamento & purificação , Ensaios de Triagem em Larga Escala , Concentração Inibidora 50 , Cinética , Luteolina/química , Luteolina/isolamento & purificação , Monofenol Mono-Oxigenase/isolamento & purificação , Panax/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Pironas/química , Pironas/isolamento & purificação , Pironas/farmacologia , Rizoma/química , Sementes/química , Vitis/química
2.
Int J Mol Sci ; 22(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201208

RESUMO

Tyrosinase is the central enzyme involved in the highly complex process of melanin formation, catalyzing the rate-limiting steps of this biosynthetic pathway. Due to such a preponderant role, it has become a major target in the treatment of undesired skin pigmentation conditions and also in the prevention of enzymatic food browning. Numerous phenolic-based structures from natural sources have been pointed out as potential tyrosinase inhibitors, including anthocyanins. The aim of the present study was to individually assess the tyrosinase inhibitory activity of eight purified compounds with a variable degree of structural complexity: native anthocyanins, deoxyanthocyanins, and pyranoanthocyanins. The latter two, the groups of anthocyanin-related compounds with enhanced stability, were tested for the first time. Compounds 1 to 4 (luteolinidin, deoxymalvidin, cyanidin-, and malvidin-3-O-glucoside) revealed to be the most effective inhibitors, and further kinetic studies suggested their inhibition mechanism to be of a competitive nature. Structure-activity relationships were proposed based on molecular docking studies conducted with mushroom tyrosinase (mTYR) and human tyrosinase-related protein 1 (hTYRP1) crystal structures, providing information about the binding affinity and the different types of interactions established with the enzyme's active center which corroborated the findings of the inhibition and kinetic studies. Overall, these results support the applicability of these compounds as pigmentation modulators.


Assuntos
Antocianinas/química , Antocianinas/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Catálise , Simulação por Computador , Humanos , Técnicas In Vitro , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxirredução , Relação Estrutura-Atividade
3.
Appl Environ Microbiol ; 87(19): e0087821, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34288703

RESUMO

Fungal unspecific peroxygenases (UPOs) are emergent biocatalysts that perform highly selective C-H oxyfunctionalizations of organic compounds, yet their heterologous production at high levels is required for their practical use in synthetic chemistry. Here, we achieved functional expression of two new unusual acidic peroxygenases from Candolleomyces (Psathyrella) aberdarensis (PabUPO) in yeasts and their production at a large scale in a bioreactor. Our strategy was based on adopting secretion mutations from an Agrocybe aegerita UPO mutant, the PaDa-I variant, designed by directed evolution for functional expression in yeast, which belongs to the same phylogenetic family as PabUPOs, long-type UPOs, and shares 65% sequence identity. After replacing the native signal peptides with the evolved leader sequence from PaDa-I, we constructed and screened site-directed recombination mutant libraries, yielding two recombinant PabUPOs with expression levels of 5.4 and 14.1 mg/liter in Saccharomyces cerevisiae. These variants were subsequently transferred to Pichia pastoris for overproduction in a fed-batch bioreactor, boosting expression levels up to 290 mg/liter, with the highest volumetric activity achieved to date for a recombinant peroxygenase (60,000 U/liter, with veratryl alcohol as the substrate). With a broad pH activity profile, ranging from pH 2.0 to 9.0, these highly secreted, active, and stable peroxygenases are promising tools for future engineering endeavors as well as for their direct application in different industrial and environmental settings. IMPORTANCE In this work, we incorporated several secretion mutations from an evolved fungal peroxygenase to enhance the production of active and stable forms of two unusual acidic peroxygenases. The tandem-yeast expression system based on S. cerevisiae for directed evolution and P. pastoris for overproduction on an ∼300-mg/liter scale is a versatile tool to generate UPO variants. By employing this approach, we foresee that acidic UPO variants will be more readily engineered in the near future and adapted to practical enzyme cascade reactions that can be performed over a broad pH range to oxyfunctionalize a variety of organic compounds.


Assuntos
Agaricales/enzimologia , Agaricales/genética , Oxigenases de Função Mista/genética , Reatores Biológicos , Fermentação , Mutação , Pichia/genética , Engenharia de Proteínas , Saccharomyces cerevisiae/genética
4.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070680

RESUMO

We previously reported (E)-ß-phenyl-α,ß-unsaturated carbonyl scaffold ((E)-PUSC) played an important role in showing high tyrosinase inhibitory activity and that derivatives with a 4-substituted resorcinol moiety as the ß-phenyl group of the scaffold resulted in the greatest tyrosinase inhibitory activity. To examine whether the 4-substituted resorcinol moiety could impart tyrosinase inhibitory activity in the absence of the α,ß-unsaturated carbonyl moiety of the (E)-PUSC scaffold, 10 urolithin derivatives were synthesized. To obtain more candidate samples, the lactone ring in synthesized urolithins was reduced to produce nine reduced urolithins. Compounds 1c (IC50 = 18.09 ± 0.25 µM), 1h (IC50 = 4.14 ± 0.10 µM), and 2a (IC50 = 15.69 ± 0.40 µM) had greater mushroom tyrosinase-inhibitory activities than kojic acid (KA) (IC50 = 48.62 ± 3.38 µM). The SAR results suggest that the 4-substituted resorcinol motif makes an important contribution to tyrosinase inhibition. To investigate whether these compounds bind to human tyrosinase, a human tyrosinase homology model was developed. Docking simulations with mushroom and human tyrosinases showed that 1c, 1h, and 2a bind to the active site of both tyrosinases with higher binding affinities than KA. Pharmacophore analyses showed that two hydroxyl groups of the 4-substituted resorcinol entity act as hydrogen bond donors in both mushroom and human tyrosinases. Kinetic analyses indicated that these compounds were all competitive inhibitors. Compound 2a inhibited cellular tyrosinase activity and melanogenesis in α-MSH plus IBMX-stimulated B16F10 melanoma cells more strongly than KA. These results suggest that 2a is a promising candidate for the treatment of skin pigment disorders, and show the 4-substituted resorcinol entity importantly contributes to tyrosinase inhibition.


Assuntos
Agaricales/enzimologia , Cumarínicos , Inibidores Enzimáticos , Proteínas Fúngicas , Melanoma/enzimologia , Monofenol Mono-Oxigenase , Proteínas de Neoplasias/antagonistas & inibidores , Resorcinóis , Animais , Linhagem Celular Tumoral , Cumarínicos/química , Cumarínicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/metabolismo , Humanos , Melaninas/biossíntese , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Proteínas de Neoplasias/metabolismo , Resorcinóis/química , Resorcinóis/farmacologia
5.
Toxins (Basel) ; 13(4)2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917246

RESUMO

Ageritin is a specific ribonuclease, extracted from the edible mushroom Cyclocybe aegerita (synonym Agrocybe aegerita), which cleaves a single phosphodiester bond located within the universally conserved alpha-sarcin loop (SRL) of 23-28S rRNAs. This cleavage leads to the inhibition of protein biosynthesis, followed by cellular death through apoptosis. The structural and enzymatic properties show that Ageritin is the prototype of a novel specific ribonucleases family named 'ribotoxin-like proteins', recently found in fruiting bodies of other edible basidiomycetes mushrooms (e.g., Ostreatin from Pleurotus ostreatus, Edulitins from Boletus edulis, and Gambositin from Calocybe gambosa). Although the putative role of this toxin, present in high amount in fruiting body (>2.5 mg per 100 g) of C. aegerita, is unknown, its antifungal and insecticidal actions strongly support a role in defense mechanisms. Thus, in this review, we focus on structural, biological, antipathogenic, and enzymatic characteristics of this ribotoxin-like protein. We also highlight its biological relevance and potential biotechnological applications in agriculture as a bio-pesticide and in biomedicine as a therapeutic and diagnostic agent.


Assuntos
Agaricales/enzimologia , Carpóforos/enzimologia , Micotoxinas/metabolismo , Ribonucleases/metabolismo , Agaricales/genética , Animais , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Antivirais/farmacologia , Agentes de Controle Biológico/farmacologia , Carpóforos/genética , Humanos , Micotoxinas/genética , Micotoxinas/farmacologia , Filogenia , Conformação Proteica , Ribonucleases/genética , Ribonucleases/farmacologia , Relação Estrutura-Atividade
6.
Molecules ; 26(8)2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920683

RESUMO

In this study, a series of coumarin derivatives were synthesized and their inhibitory effects on the activity of mushroom tyrosinase were evaluated. As a result of measuring the inhibition of tyrosinase activity of these derivatives, the compounds 3e (1.05 µM), 3f (0.83 µM), 3h (0.85 µM), 3i (1.05 µM), and 3k (0.67 µM) of the geranyloxycoumarin derivatives were highly active at a concentration of 0.8%. The geranyloxycoumarin derivatives exhibited better activity than the hydroxycoumarin derivatives. Among the geranyloxycoumarin derivatives, compound 3k was two times more active than arbutin, a positive control, at a concentration of 0.4%. The above results suggest that geranyloxycoumarin derivatives have great potential for application as functional cosmetic ingredients with tyrosinase-inhibiting activity.


Assuntos
Cumarínicos/química , Inibidores Enzimáticos/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Pele/efeitos dos fármacos , Agaricales/enzimologia , Cosméticos , Cumarínicos/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Monofenol Mono-Oxigenase/química , Pele/enzimologia
7.
Molecules ; 26(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806398

RESUMO

Bruguiera gymnorhiza (L.) Lam is a mangrove plant that spread in many parts of the world. Though mangrove plant polyphenols have been reported to exhibit many biological activities, little is known about mangrove plant tannins. To explore the application value of tannins from B. gymnorhiza, analyses on the structure and biological activity of condensed tannins (CTs) from Bruguiera gymnorhiza (L.) Lam were carried out. The results from 13C nuclear magnetic resonance (13C-NMR) and reversed-phase, high-performance liquid chromatography (RP-HPLC) showed that the CTs were dominated by procyanidins, with a small quantity of prodelphinidins and propelargonidins; and that the monomeric constituents of B. gymnorhiza tannins were catechin/epicatechin, gallocatechin/epigallocatechin and afzelechin/epiafzelechin. The CTs were reversible and mixed competitive inhibitors of tyrosinase and the 50% inhibiting concentration (IC50) was estimated to be 123.90 ± 0.140 µg/mL. The antioxidant activities of CTs from B. gymnorhiza leaves were evaluated, the IC50 for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid diammonium salt) (ABTS) scavenging activities were 88.81 ± 0.135 and 105.03 ± 0.130 µg/mL, respectively, and the ferric ion reducing antioxidant power (FRAP) value was 1052.27 ± 4.17 mgAAE/g. In addition, the results from fresh-keeping assays on fresh-cut lotus root reveal that CTs from B. gymnorhiza had excellent effects on inhibiting the activities of polyphenol oxidase (PPO) and peroxidase (POD), protecting fresh-cut lotus root from the oxidation of total phenolics and malondialdehyde (MDA) content and slowing the increase in total phenol content (TPC) at 4 °C during the whole storage period. Therefore, CTs showed good effects against the browning of fresh-cut lotus root. Together, these results suggested that B. gymnorhiza CTs are promising antibrowning agents for fresh-cut fruits.


Assuntos
Antioxidantes/farmacologia , Lotus/efeitos dos fármacos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Raízes de Plantas/efeitos dos fármacos , Rhizophoraceae/química , Taninos/farmacologia , Agaricales/enzimologia , Oxirredução , Proantocianidinas/análise , Taninos/isolamento & purificação
8.
Dokl Biochem Biophys ; 496(1): 14-17, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33689067

RESUMO

The recently described bioluminescent system from fungi has great potential for developing highly efficient tools for biomedical research. Luciferase enzyme is one of the most crucial components of this system. The luciferase from Neonothopanus nambi fungus belongs to the novel still undescribed protein family. The structure data for this protein is almost absent. A detailed study of the N. nambi luciferase properties is necessary for the improvement of analytical methods based on the fungal bioluminescent system. Here we present the positions of key amino acid residues and their effect on enzyme function described using bioinformatic and experimental approaches. These results are useful for further fungal luciferase structure determination.


Assuntos
Agaricales/enzimologia , Proteínas Fúngicas/química , Luciferases/química , Agaricales/genética , Sequência de Aminoácidos , Domínio Catalítico , Biologia Computacional/métodos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Luciferases/genética , Luciferases/metabolismo , Luminescência , Modelos Moleculares , Mutagênese , Mutação , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
9.
Molecules ; 26(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670416

RESUMO

Growing scientific evidence indicates that Achillea biebersteinii is a valuable source of active ingredients with potential cosmetic applications. However, the data on its composition and pharmacological properties are still insufficient. This study aims to optimize the extraction procedure of the plant material, evaluate its phytochemical composition, and compare anti-tyrosinase potential of A. biebersteinii extracts obtained by various methods. In order to identify compounds responsible for the tyrosinase inhibitory activity of A. biebersteinii, the most active anti-tyrosinase extract was fractionated by column chromatography. The fractions were examined for their skin lightening potential by mushroom and murine tyrosinase inhibitory assays and melanin release assay. HPLC-ESI-Q-TOF-MS/MS analysis of the total extract revealed the presence of several phenolic acids, flavonoids, flavonoid glucosides, and carboxylic acid. Among them, fraxetin-8-O-glucoside, quercetin-O-glucopyranose, schaftoside/isoschaftoside, gmelinin B, 1,3-dicaffeoylquinic acid (1,3-DCQA), and ferulic acid were found in the fractions with the highest skin lightening potential. Based on obtained qualitative and quantitative analysis of the fractions, it was assumed that the caffeoylquinic acid derivatives and dicaffeoylquinic acid derivatives are more likely responsible for mushroom tyrosinase inhibitory activity of A. biebersteinii extracts and fractions. Ferulic acid was proposed as the most active murine tyrosinase inhibitor, responsible also for the reduced melanin release from B16F10 murine melanoma cells.


Assuntos
Achillea/química , Agaricales/enzimologia , Inibidores Enzimáticos/isolamento & purificação , Monofenol Mono-Oxigenase/química , Animais , Antioxidantes/química , Inibidores Enzimáticos/química , Flavonoides/química , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Compostos Fitoquímicos/química , Extratos Vegetais/química , Espectrometria de Massas em Tandem
10.
Commun Biol ; 4(1): 223, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597725

RESUMO

Enzymes empower chemical industries and are the keystone for metabolic engineering. For example, linalool synthases are indispensable for the biosynthesis of linalool, an important fragrance used in 60-80% cosmetic and personal care products. However, plant linalool synthases have low activities while expressed in microbes. Aided by bioinformatics analysis, four linalool/nerolidol synthases (LNSs) from various Agaricomycetes were accurately predicted and validated experimentally. Furthermore, we discovered a linalool synthase (Ap.LS) with exceptionally high levels of selectivity and activity from Agrocybe pediades, ideal for linalool bioproduction. It effectively converted glucose into enantiopure (R)-linalool in Escherichia coli, 44-fold and 287-fold more efficient than its bacterial and plant counterparts, respectively. Phylogenetic analysis indicated the divergent evolution paths for plant, bacterial and fungal linalool synthases. More critically, structural comparison provided catalytic insights into Ap.LS superior specificity and activity, and mutational experiments validated the key residues responsible for the specificity.


Assuntos
Monoterpenos Acíclicos/metabolismo , Agaricales/enzimologia , Biologia Computacional , Proteínas Fúngicas/metabolismo , Hidroliases/metabolismo , Microbiologia Industrial , Agaricales/genética , Evolução Molecular , Proteínas Fúngicas/genética , Hidroliases/genética , Cinética , Filogenia , Conformação Proteica , Relação Estrutura-Atividade
11.
Carbohydr Res ; 501: 108259, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33610932

RESUMO

Two new iridoid glycosides, genipin 1,10-di-O-α-l-rhamnoside (1) and genipin 1,10-di-O-ß-d-xylopyranoside (2), along with thirteen known compounds (3-15) were isolated from Gardeniae Fructus. Their structures were elucidated by physical data analyses such as NMR, UV, IR, HR-ESI-MS, as well as chemical hydrolysis. All compounds were tested for their tyrosinase inhibitory and antioxidant activities. At a concentration of 25 µM, compound 13 showed obvious mushroom tyrosinase inhibition activity with % inhibition value of 36.52 ± 1.98%, with kojic acid used as the positive control (46.09 ± 1.29%). At a concentration of 1 mM, compounds 8 and 9 exhibited considerable DPPH radical scavenging activities, with radical scavenging rates of 48.54 ± 0.47%, 58.59 ± 0.39%, respectively, with l-ascorbic acid used as the positive control (59.02 ± 0.77%).


Assuntos
Inibidores Enzimáticos/farmacologia , Gardenia/química , Glicosídeos Iridoides/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Configuração de Carboidratos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Glicosídeos Iridoides/química , Glicosídeos Iridoides/isolamento & purificação , Monofenol Mono-Oxigenase/metabolismo
12.
Int J Biol Macromol ; 174: 77-88, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33508361

RESUMO

A new anti-tumor protein (designated as Boletus edulis or in short BEAP) was isolated from dried fruit bodies of the edible bolete mushroom Boletus edulis. The purification protocol employed comprised fast ion exchange chromatography on a Hitrap Q column and ion exchange chromatography on a DEAE-52 cellulose column. Superdex G75 gel filtration and SDS-PAGE analysis revealed that BEAP was a protein with a molecular weight of 16.7 KD. The protein exhibited potent anti-cancer activity on A549 cells both in vitro and in vivo. With the use of AO/EB staining, annexin V-FITC/PI, and Western blotting, it was demonstrated in vitro that the cytotoxicity of BEAP was mediated by induction of apoptosis and arrest of A549 cells in the G1 phase of the cell cycle. BEAP significantly suppressed the growth of A549 solid tumors in vivo. These results prove that BEAP is a new multifunctional protein with anti-tumor and anti-metastasis capabilities.


Assuntos
Basidiomycota/enzimologia , Basidiomycota/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Células A549/efeitos dos fármacos , Agaricales/química , Agaricales/enzimologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células/efeitos dos fármacos , Cromatografia em Gel/métodos , Cromatografia por Troca Iônica/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Feminino , Carpóforos/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas/análise , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
13.
Bioorg Med Chem Lett ; 36: 127826, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33513384

RESUMO

Theophylline is long known for its anti-ageing and anti-oxidative properties. Moreover, Tyrosinase is a crucial enzyme that regulates the melanin synthetic pathway, which is involved in various physiological metabolic processes including aging. The current paper describes the synthesis of various heterocyclic systems coupled with theophylline moiety along with their tyrosinase inhibition activity in view to identify the potent nucleus. Around 19 compounds were synthesized and screened for enzyme inhibition. Based on the current study, it is suggested that compound 18 having thiosemicarbazide has strong enzyme inhibition potential. The enzyme kinetics and docking studies provide important insights into how the compound interacts with the mushroom tyrosinase active site. The work will provide clue to developing new, potent tyrosinase inhibitors for drug development.


Assuntos
Complexos de Coordenação/farmacologia , Cobre/farmacologia , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Semicarbazidas/farmacologia , Teofilina/farmacologia , Agaricales/enzimologia , Sítios de Ligação , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cobre/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Modelos Moleculares , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Semicarbazidas/química , Relação Estrutura-Atividade , Teofilina/química
14.
Fitoterapia ; 150: 104828, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33434632

RESUMO

Tyrosinase is the key enzyme in the production of melanin. Tyrosinase inhibitors have gained interest in the cosmetics industry to prevent hyperpigmentation and skin-related disorders by inhibiting melanin production. It has been reported that several Aloe species exhibit anti-tyrosinase efficacy in vitro. In this study, the exudates of thirty-nine South African Aloe species were screened to identify species and compounds with anti-tyrosinase activity. Qualitative screening revealed that twenty-nine Aloe species exhibited tyrosinase inhibition activity with one to three active bands. Quantitative screening was performed for 29 species and expressed as IC50 values. Three species were further analysed and subsequently, aloesin and aloeresin A was isolated from A. ferox and plicataloside from A. plicatilis and A. chabaudii. Aloeresin A was determined to be a substrate of mushroom tyrosinase. Dose-response assays showed that aloesin (IC50 = 31.5 µM) and plicataloside (IC50 = 84.1 µM) exhibited moderate to weak activity. Molecular docking scores for plicataloside were considerably lower than for aloesin (P < 0.01), confirming its lower IC50. Several Aloe species may have potential for the management of hyperpigmentation or as a skin lightening agent. This is the first report showing that plicataloside, present in A. plicatilis and A. chabaudii, exhibits anti-tyrosinase activity.


Assuntos
Aloe/química , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Glucosídeos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/enzimologia , Aloe/classificação , Cromonas/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Glucosídeos/isolamento & purificação , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , África do Sul
15.
Chem Pharm Bull (Tokyo) ; 69(1): 40-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390520

RESUMO

An investigation into the methanol extracts obtained from the stems of Dodonaea viscosa led to the isolation of one nor-clerodane diterpene (1) and two labdane diterpenes (2, 3), as well as 17 known compounds (4-20). The structures of these compounds were elucidated based on chemical and spectral evidence. The stereochemical structure of the nor-clerodane diterpene was confirmed via its circular dichroism spectrum and calculated electronic circular dichroism spectrum. Isolated compounds were evaluated for their inhibitory effects on collagenase and tyrosinase. Since 5,7,4'-trihydroxy-3'-(4-hydroxy-3-methylbutyl)-5'-(3-methylbut-2-enyl)-3,6-dimethoxyflavone (9) showed collagenase inhibitory activity and scopoletin (12) had significant tyrosinase inhibitory activity, they were considered to be good candidates for cosmetic agents.


Assuntos
Diterpenos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Sapindaceae/química , Agaricales/enzimologia , Diterpenos/química , Diterpenos/farmacologia , Gelatinases/antagonistas & inibidores , Gelatinases/metabolismo , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estereoisomerismo
16.
Biotechnol Lett ; 43(4): 845-854, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33389270

RESUMO

The aim of this study was to characterize the growth of the fungus Leucoagaricus gongylophorus LEU18496, isolated from the fungus garden of the nest of leaf cutter ants Atta mexicana. The fungus garden was cultivated in an artificial laboratory nest and the fungus further grown in submerged (SmC) and solid state (SSC) cultures with sugarcane bagasse, grass or model substrates containing CM-cellulose, xylan or lignin. The CO2 production rate with grass in SmC (Vmax 34.76 mg CO2 Lgas-1 day- 1) was almost four times than SSC (Vmax 9.49 mg CO2 Lgas-1 day- 1), while the production rate obtained in sugarcane bagasse in SmC (Vmax 16.02 mg CO2 Lgas-1 day- 1) was almost three times than that for SSC (Vmax 5.42 mg CO2 Lgas-1 day- 1). In addition, the fungus grew with defined carbon substrates mixtures in SmC, but at different rates, first xylan, followed by CM-cellulose and lignin. Endoglucanase and xylanase activities (U mgprotein-1) were detected in all cultures, the specific activity was higher in the fungus-garden, 5.2 and 1.8; followed by SSC-grass, 1.5 and 0.8, and SSC-bagasse, 0.9 and 0.8, respectively. Laccase activity in the fungus-garden was 44.8 U L- 1 and 10.9 U L- 1 in the SSC-grass. The gongylidia structures observed by environmental scanning electron microscopy were ca. 40 µm and the hyphae width ca. 5 µm. The results show that L. gongylophorus from A. mexicana have promising applications for the treatment of plant residues to release fermentable sugars and the production of high value lignocellulolytic enzymes such as endoglucanase, xylanase or laccases.


Assuntos
Agaricales/crescimento & desenvolvimento , Formigas/microbiologia , Celulase/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Lignina/metabolismo , Agaricales/enzimologia , Agaricales/isolamento & purificação , Animais , Celulose/química , Cromatografia Gasosa , Fermentação , Proteínas Fúngicas/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Microscopia Eletrônica de Varredura , Folhas de Planta/parasitologia
17.
Food Chem ; 341(Pt 2): 128265, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33031957

RESUMO

A series of 1,2,4-triazole hydrazones (1-16) were synthesized, and their inhibitory activities and mechanisms on tyrosinase were investigated by ultraviolet spectrophotometry, fluorescence quenching, molecular docking study, etc. Most of compounds possessed potent tyrosinase inhibitory activity. Thereinto, compound 9 presented the superior activity with IC50 of 0.9 µM, which was markedly lower than the standard kojic acid (IC50 = 64.1 µM). Compound 9 not only interacted with copper ions in the active center of the enzyme but also bound to the enzyme-substrate complex, indicating that it was a competitive-noncompetitive mixed inhibitor. Additionally, it also displayed potent DPPH scavenging activity. Antibrowning test showed that compound 9 effectively reduced the enzymatic browning of fresh-cut potatoes. Furthermore, compound 9 exhibited low cytotoxic activity against human normal cell line with IC50 of 49.9 µM. Overall, the present study suggests that these compounds may serve as lead molecules for developing novel antibrowning agents in food industry.


Assuntos
Antioxidantes/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Hidrazonas/síntese química , Hidrazonas/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Triazóis/química , Agaricales/enzimologia , Sobrevivência Celular/efeitos dos fármacos , Quelantes/farmacologia , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Oxirredução , Relação Estrutura-Atividade
18.
Int J Biol Macromol ; 167: 369-381, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33275974

RESUMO

Laccases or benzenediol oxygen oxidoreductases (EC 1.10.3.2) are polyphenol multicopper oxidases that are known for their structural and functional diversity in various life forms. In the present study, the molecular and physico-chemical properties (redox-potential and secondary structures) of fungal laccase isozymes (FLIs) isolated from a medicinal mushroom Ganoderma lucidum were analyzed and compared with those of the recombinant bacterial laccases (rLac) obtained from different Yersinia enterocolitica strains. It was revealed that the FLIs contained His-Cys-His as the most conserved residue in its domain I Cu site, while the fourth and fifth residues were variable (Ile, Leu, or Phe). Evidently, the cyclic voltammetric measurements of Glac L2 at Type 1 Cu site revealed greater E° for ABTS/ABTS+ (0.312 V) and ABTS+/ABTS2+ (0.773 V) compared to the E° of rLac. Furthermore, circular dichroism-based conformational analysis revealed structural stability of the FLIs at acidic pH (3.0) and low temperature (<30 °C), while the isozymes were destabilized at neutral pH (7.0) and high-temperature conditions (>70 °C). The zymographic studies further confirmed the functional inactivation of FLIs at high temperatures (≥70 °C), predominantly due to domain unfolding. These findings provide novel insight into the evolution of the catalytic efficiency and redox properties of the FLIs, contributing to the existing knowledge regarding stress responses, metabolite production, and the biotechnological utilization of metabolites.


Assuntos
Agaricales/enzimologia , Lacase/química , Oxirredução , Reishi/enzimologia , Yersinia enterocolitica/enzimologia , Agaricales/classificação , Agaricales/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Estabilidade Enzimática , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Perfilação da Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Isoenzimas , Lacase/genética , Lacase/isolamento & purificação , Ligantes , Modelos Moleculares , Filogenia , Conformação Proteica , Reishi/classificação , Reishi/genética , Análise Espectral , Relação Estrutura-Atividade , Transcriptoma
19.
Biotechnol Appl Biochem ; 68(3): 497-512, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32432341

RESUMO

Enzyme activity modulation by synthetic compounds provide strategies combining the inhibitory and therapeutic mode of action of the confirmed inhibitors. However, natural modulators could offer a valuable alternative for synthetic ones for the treatment of different chronic diseases (diabetes, hypertension, cancer); due to the numerous side effects of the latter. In vitro screening assays were conducted for Psidium guajava leaf methanolic extract against three metabolism-related enzymes; α-amylase, tyrosinase, and hyaluronidase. The obtained results showed that the examined extract retained weak and moderate multitarget inhibition against α-amylase, tyrosinase, and hyaluronidase, respectively; however, the leaf fractions exhibited stronger inhibitions for the three investigated enzymes. Fractionation of P. guajava leaf extract revealed that anthraquinones and ellagic acid are of the major active compounds with inhibitory activities for α-amylase, tyrosinase, and hyaluronidase. Kinetic studies showed that quinalizarin inhibition is competitive for both α-amylase and hyaluronidase, and ellagic acid inhibition for tyrosinase and hyaluronidase is competitive and un-competitive, respectively. The molecular docking studies of quinalizarin and ellagic acid with α-amylase, tyrosinase, and hyaluronidase showed high binding energies with different bonds stabilizing the ligand-protein complex. Compiling all obtained results led to conclude that both P. guajava leaf fractions, quinalizarin and ellagic acid, have multitarget activities with potential therapeutic applications in many metabolic disorders.


Assuntos
Inibidores Enzimáticos/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Psidium/química , Agaricales/enzimologia , Animais , Aspergillus oryzae/enzimologia , Bovinos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
20.
Nat Prod Res ; 35(6): 1024-1028, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31135222

RESUMO

Chemical isolation and bioactivity studies were conducted on the stamens of Mesua ferrea L., which are being used in a traditional skincare formulation in Myanmar. Rhusflavanone and mesuaferrone B were obtained as the main biflavonoids together with lupeol, five common flavonoids, and five phenolic compounds. After being identified by NMR and other spectroscopic analyses, these compounds were evaluated for their 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging, human leukocyte elastase inhibitory, and mushroom tyrosinase inhibitory activities. The two biflavonoids exhibited strong inhibitory activities against elastase and tyrosinase, but low DPPH-radical scavenging activities. The contents of rhusflavanone and mesuaferrone B in the stamens were 0.35 ± 0.04% and 0.55 ± 0.06%, respectively. Moreover, lupeol was considered to be a cosmetically important component of the stamens because of its high content and strong elastase inhibitory activity. Rhusflavanone was reported to be isolated from M. ferrea for the first time.


Assuntos
Benzopiranos/isolamento & purificação , Benzopiranos/farmacologia , Biflavonoides/isolamento & purificação , Biflavonoides/farmacologia , Inibidores Enzimáticos/farmacologia , Flores/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Elastase Pancreática/antagonistas & inibidores , Agaricales/enzimologia , Benzopiranos/química , Biflavonoides/química , Inibidores Enzimáticos/química , Humanos , Monofenol Mono-Oxigenase/metabolismo , Elastase Pancreática/metabolismo
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