Tyrosinase Inhibitory Activity Research Articles

Assessment of in vitro anti-skin aging activities of Phyllanthus indofischeri Bennet extracts for dermatological and aesthetic applications

Giant Indian Gooseberry (GIG) or Phyllanthus indofischeri Bennet are commercially cultivated and commonly used herbs in Traditional medicine, especially in Thailand. The aim of this study was to assess the potential of the GIG extracts in anti-aging activities to be a dermatological application. The juice, meat residues, and seeds of GIG collected from Sra Kaeo Province, Thailand, were extracted by the Boiling method (B) and the Maceration process (M) by using 95% ethanol as a solvent. The GIG extracts gave the total phenolic, total flavonoid contents and quercetin contents, as well as exhibited anti-oxidative activities. The GIG-R-B extract inhibited tyrosinase activity and had the highest anti-melanogenesis activity on B16F10 cells at 31.63 ± 0.70%. The GIG-S-B, GIG-S-M, and GIG-R-M extracts demonstrated the highest collagen biosynthesis, which was comparable to vitamin C (p < 0.05), whereas the GIG-R-B extracts gave the highest stimulation of anti-aging genes (SIRT1 and FOXO1). All extracts at the concentration of 0.1 mg/mL showed no cytotoxicity on human skin fibroblasts. Therefore, the GIG-S-B extract was discovered to be a promising natural anti-aging agent for dermatological health and aesthetic applications that can be further developed in cosmetic, functional food and food supplement industries.

Comparative Study on the Chemical Profile, Antioxidant Activity, and Enzyme Inhibition Capacity of Red and White Hibiscus sabdariffa Variety Calyces.

Hibiscus sabdariffa L. (Family: Malvaceae) is believed to be domesticated by the people of western Sudan sometime before 4000 BC for their nutritional and medicinal properties. This study aimed to investigate the chemical profile, antioxidant activity, and enzyme inhibition property of extracts from red roselle (RR) and white roselle (WR) varieties grown in Sudan. Three aqueous extracts obtained by maceration, infusion, and decoction, in addition to the methanolic one, were prepared from the two roselle varieties. Results showed that the highest total phenolic and flavonoid contents of RR were obtained from the extracts prepared by infusion (28.40 mg GAE/g) and decoction (7.94 mg RE/g) respectively, while those from the WR were recorded from the methanolic extract (49.59 mg GAE/g and 5.81 mg RE/g respectively). Extracts of RR were mainly characterized by high accumulation of chlorogenic acid (6502.34-9634.96 mg kg-1), neochlorogenic acid (937.57-8949.61 mg kg-1), and gallic acid (190-4573.55 mg kg-1). On the other hand, neochlorogenic acid (1777.05-6946.39 mg kg-1) and rutin (439.29-2806.01 mg kg-1) were the dominant compounds in WR. All extracts from RR had significant (p < 0.05) higher antioxidant activity than their respective WR except in their metal chelating power, where the methanolic extract of the latter showed the highest activity (3.87 mg EDTAE/g). RR extracts prepared by infusion recorded the highest antioxidant values (35.09, 52.17, 65.62, and 44.92 mg TE/g) in the DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), CUPRAC (cupric ion reducing antioxidant capacity), and FRAP (ferric reducing antioxidant power) assays, respectively. All aqueous extracts from the WR exerted significant (p < 0.05) acetylcholinesterase (AChE) inhibitory activity (3.42-4.77 mg GALAE/g; GALAE = galantamine equivalents), while only one extract, obtained by maceration, from RR exerted AChE inhibitory activity (4.79 mg GALAE/g). All extracts of the RR showed relatively higher BChE (butyrylcholinesterase) inhibitory activity (3.71-4.23 mg GALAE/g) than the WR ones. Methanolic extracts of the two roselle varieties displayed the highest Tyr (tyrosinase) inhibitory activity (RR = 48.25 mg KAE/g; WR = 42.71 mg KAE/g). The methanolic extract of RR exhibited the highest amylase (0.59 mmol ACAE/g) and glucosidase (1.46 mmol ACAE/g) inhibitory activity. Molecular docking analysis showed that delphinidin 3,5-diglucoside, rutin, isoquercitrin, hyperoside, and chlorogenic acid exerted the most promising enzyme inhibitory effect. In conclusion, these findings indicated that the chemical profiles and biological activity of roselle varied according to the variety, extraction solvent, and technique used. These two roselle varieties can serve as a valuable source for the development of multiple formulations in food, pharmaceutical, and cosmetic industries.

Optimization of a Novel Tyrosinase Inhibitory Peptide from Atrina pectinata Mantle and Its Molecular Inhibitory Mechanism.

In order to realize the multi-level utilization of marine shellfish resources and to develop the potential biological activity of processing by-products of Atrina pectinata, gelatin was extracted from the mantle and the potential whitening effect of its enzymatic peptides was explored. Taking tyrosinase inhibitory activity as the evaluation index, the enzyme hydrolysate process was optimized by response-surface methodology, and the optimal enzyme hydrolysate conditions were as follows: pH 5.82, 238 min enzyme hydrolysate time, and temperature of 54.5 °C. Under these conditions, the tyrosinase inhibition activity of Atrina pectinata mantle gelatin peptide (APGP) was 88.6% (IC50 of 3.268 ± 0.048 mg/mL). The peptides obtained from the identification were separated by ultrafiltration and LC-MS/MS, and then four new peptides were screened by molecular docking, among which the peptide Tyr-Tyr-Pro (YYP) had the strongest inhibitory effect on tyrosinase with an IC50 value of 1.764 ± 0.025 mM. The molecular-docking results indicated that hydrogen bonding is the main driving force for the interaction of the peptide YYP with tyrosinase. From the Lineweaver-Burk analysis, it could be concluded that YYP is inhibitory to tyrosinase and exhibits a mixed mechanism of inhibition. These results suggest that YYP could be widely used as a tyrosinase inhibitor in whitening foods and pharmaceuticals.

Enhancing thermostability of alkaline κ-carrageenase from Pseudoalteromonas tetraodonis by rational design of disulfide bonds

The industrial applications of the κ-carrageenases have been restricted by their poor thermostability. In this study, based on the structural information of alkaline κ-carrageenase from Pseudoalteromonas tetraodonis (WT) and with the aid of Disulfide by Design2 computational tool, two disulfide bond mutants of K44C-A119C and T120C-Q250C were identified with improved thermostability and enzymatic activity. K44C-A119C and T120C-Q250C increased the enzyme activity by 19.0% and 7.3%, respectively. After treatment at 50 °C for 30 min, the residual activities of K44C-A119C, T120C-Q250C, and WT were 80.1%, 78.6%, and 45.4%, respectively. The Tm values of K44C-A119C, T120C-Q250C, and WT determined by differential scanning calorimetry were 56.0 °C, 54.8 °C, and 51.2 °C, respectively. The increasement of disulfide bond and its adjacent non-covalent interactions would account for the increased thermostability of the mutants. Molecular dynamics simulation analysis revealed that the improved thermostability and catalytic activities of K44C-A119C and T120C-Q250C could be attributed to the increased flexibility of finger F6 and the less structural deviation in some loops and β-sheets. In addition, the κ-carrageenan hydrolysates by K44C-A119C exhibited higher tyrosinase inhibitory activity than the untreated κ-carrageenan. These findings provide a useful strategy to improve κ-carrageenases’ thermostability and enzyme activity for their better industrial applications.

Benzylidine‐N‐phenylhydrazine‐1‐carboxamide Derivatives as Tyrosinase Inhibitors: Design, Preparation, Molecular Docking, and Biological Activity

AbstractTen novel benzylidine‐N‐phenylhydrazine‐1‐carboxamide derivatives (7 a–7 j) were synthesized in three steps and evaluated for their tyrosinase inhibitory and antioxidant activities. The spectrophotometric method with L–DOPA as a substrate was used to determine tyrosinase inhibitory activities, and a DPPH assay was used to evaluate antioxidant properties. Among the synthesized compounds, compound 7 c with an ethyl substitution on the C2‐N‐phenylacetamide ring showed the highest tyrosinase‐inhibition activity (IC50=4.36±1.58 μM), which was comparable with that of standard kojic acid (IC50=16.34±1.93 μM). Compounds (7 d) and (7 e) showed potent antioxidant activities (EC50=52.11±4.18 and 92.47±3.32 μM, respectively), which were comparable to those of quercetin. The study of the interactions and binding modes of the tested compounds was accomplished with molecular docking. Docking results corroborated that the active inhibitors were well placed in the mushroom tyrosinase enzyme‘s active site.

Chemical characterization, antioxidant, antimicrobial, enzyme inhibitory and cytotoxic activities of Illicium lanceolatum essential oils

Illicium lanceolatum is a medicinal and aromatic plant widely distributed in the south of China. The reports on chemical composition and biological activities of its essential oils (EOs) were very limited. In this study, Illicium lanceolatum EOs were extracted by hydro distillation, and analyzed by GC–MS and GC-FID. DPPH radical scavenging assay, ABTS cation radical scavenging assay and ferric reducing/antioxidant power (FRAP) assay were used for antioxidant activity evaluation. Minimum inhibitory concentrations (MICs) and minimum microbiocidal concentrations (MMCs) against 9 microorganisms were determined. The inhibitory effects on tyrosinase, α-glucosidase and cholinesterases were evaluated and cytotoxic activities were evaluated using MTT assay. The results revealed 110 identified compounds, with asaricin, eucalyptol, linalool and caryophyllene oxide as major compounds. Eucalyptol was the most abundant compound in the stem, leaf and fruit EOs while asaricin accounted for 50.52 ± 0.33 % in the root EO. Very weak radical scavenging capacities were noticed for all EOs, but the root EO showed moderate antioxidant activity (176.33 ± 4.52 mg TE/g of EO) in the FRAP assay, which could be attributed to asaricin. The root EO displayed better antimicrobial activities than other three EOs, with MIC values as 3.13 mg/mL against three bacteria including Staphylococcus aureus BNCC 186335, Bacillus cereus BNCC 103930 and Listeria monocytogenes BNCC 336877. Camphor and borneol were found to be important antimicrobial compounds. No inhibitory effect on α-glucosidase was found. The leaf EO displayed better acetylcholinesterase inhibitory activity (17.79 ± 0.32 mg GE/g of EO) while the root EO showed better tyrosinase (30.34 ± 0.40 mg KAE/g of EO) and butyrylcholinesterase (43.25 ± 1.50 mg GE/g of EO) inhibitory activities. Molecular docking between active compounds and enzymes revealed the main interactions as hydrophobic interaction, hydrogen bond and π-stacking. All EOs displayed weak cytotoxicity to HK-2 cells of normal kidney at six tested concentrations. The leaf EO showed strong anticancer activities to HepG2 cells at the concentration of 500 μg/mL. I. lanceolatum EOs showed promising prospects with possible applications in pharmaceutical and cosmetic industries.

Effect of an Oral Formulation on Skin Lightening: Results from In Vitro Tyrosinase Inhibition to a Double-Blind Randomized Placebo-Controlled Clinical Study in Healthy Asian Participants

Oral formulations with natural plant-based extracts represent a safe and promising strategy for skin lightening and anti-dark-spot effects, especially in Asia. This study evaluated the effect of an oral formulation including polyphenol-rich extracts and vitamin C (Belight3TM) on in vitro tyrosinase inhibitory activity and investigated its skin lightening and anti-dark-spot effects in vivo. Tyrosinase inhibitory activity of the formulation was measured with spectrophotometry. A randomized, double-blind, placebo-controlled clinical study was carried out on 58 healthy Asian males and females, aged 45–65. Skin color was measured at baseline, 6 weeks and 12 weeks with digital photographs. Color of dark spots was assessed with spectrophotometry. In vitro, the formulation showed a significant synergistic tyrosinase inhibitory activity of 85% compared to the control. In vivo, 12-week oral administration of the formulation significantly lightened the skin and was significantly better than the placebo. In addition, this formulation induced a slight and significant lightening effect of the dark spots after 6 and 12 weeks. Our findings suggest that the daily oral administration of Belight3TM during 12 weeks appears as an efficient and safe nutricosmetic to lighten the color of the facial skin and dark spots in Asian subjects.

In vitro Study of Ixora coccinea Fruit Extracts for their Antioxidant and Tyrosinase Inhibitory Activities

In vitro Study of Ixora coccinea Fruit Extracts for their Antioxidant and Tyrosinase Inhibitory Activities

A Comparative Analysis of Radical Scavenging, Antifungal and Enzyme Inhibition Activity of 3'-8″-Biflavones and Their Monomeric Subunits.

Biflavonoids are dimeric forms of flavonoids that have recently gained importance as an effective new scaffold for drug discovery. In particular, 3'-8″-biflavones exhibit antiviral and antimicrobial activity and are promising molecules for the treatment of neurodegenerative and metabolic diseases as well as cancer therapies. In the present study, we directly compared 3'-8″-biflavones (amentoflavone, bilobetin, ginkgetin, isoginkgetin, and sciadopitysin) and their monomeric subunits (apigenin, genkwanin, and acacetin) and evaluated their radical scavenging activity (with DPPH), antifungal activity against mycotoxigenic fungi (Alternaria alternata, Aspergillus flavus, Aspergillus ochraceus, Fusarium graminearum, and Fusarium verticillioides), and inhibitory activity on enzymes (acetylcholinesterase, tyrosinase, α-amylase, and α-glucosidase). All the tested compounds showed weak radical scavenging activity, while antifungal activity strongly depended on the tested concentration and fungal species. Biflavonoids, especially ginkgetin and isoginkgetin, proved to be potent acetylcholinesterase inhibitors, whereas monomeric flavonoids showed higher tyrosinase inhibitory activity than the tested 3'-8″-biflavones. Amentoflavone proved to be a potent α-amylase and α-glucosidase inhibitor, and in general, 3'-8″-biflavones showed a stronger inhibitory potential on these enzymes than their monomeric subunits. Thus, we can conclude that 3'-8″-dimerization enhanced acetylcholinesterase, α-amylase, and α-glucosidase activities, but the activity also depends on the number of hydroxyl and methoxy groups in the structure of the compound.

Synthesis of Functionalized Isoxazolines as New Acetylcholinesterase and Tyrosinase Inhibitors and Antioxidant Agents

In the search for new leads capable of interacting with multiple targets involved in NDD pathogenesis, a series of pyrazine-linked isoxazoline scaffolds were designed, synthesized and evaluated for their acetylcholinesterase and tyrosinase inhibitory potency and antioxidant activity. Isoxazolines 4a, 4d and 4h exhibited better molecular interaction with cholinesterases, tyrosinases and peroxiredoxin enzymes. Isoxazolines 4a, 4d and 4h interacted with acetylcholinesterase with the highest docking score of −9.083, −8.68 and −7.87 kcal/mol, respectively. Compound 4h ranked top when interacting with butyrylcholinesterase with a docking score of −7.926 kcal/mol, followed by 4a (−6.327 kcal/mol). 4a exhibited a robust interaction with 1HD2 with a docking score of −3.103 kcal/mol followed by 4d and 4h. 4a, 4d and 4h exhibited better docking scores of −5.47 kcal/mol, −4.63 kcal/mol and −5.157 kcal/mol with the enzyme tyrosinase. Based on the in-silico data, we have proceeded further to synthesis and in-vitro studies. Chalcones were synthesized by the Claisen-Schmidt reaction, which was cyclised to isoxazolines by the cycloaddition of hydroxylamine HCl. FTIR, 1HNMR, 13CNMR, and mass spectral studies further characterized the compounds. The prediction of pharmacokinetic parameters also supports the study, and all the compounds passed the screening. In-vitro studies were performed to evaluate acetylcholinesterase and tyrosinase inhibition. Compound 4h displayed excellent action against acetylcholinesterases and tyrosinase enzymes. Hydrogen peroxide assay determined the antioxidant effect, which found that 4h and 4d compounds exhibited higher strength as peroxide scavengers. Thus, the study shows that pyrazine-based isoxazolines with electron-withdrawing groups can be used as leads to develop a drug of choice for NDD, as it has excellent acetylcholinesterase and tyrosinase inhibitory action and tremendous peroxide scavenging effect.

Design, Synthesis, Pharmacological Activities, Structure-Activity Relationship, and In Silico Studies of Novel 5-Substituted-2-(morpholinoimino)-thiazolidin-4-ones.

This study is aimed to synthesize morpholine- and thiazolidine-based novel 5-(substituted)benzylidene)-2-(morpholinoimino)-3-phenylthiazolidin-4-ones (3-26) and characterized by molecular spectroscopy. The synthesized compounds were subjected to antioxidant activity with anticholinesterase, tyrosinase, and urease inhibition activities and evaluated the structure-activity relationship (SAR) of enzyme inhibition activities. Compound 11 was found to be the most active antioxidant. In anticholinesterase inhibition, compound 12 (IC50: 17.41 ± 0.22 μM) was the most active against AChE, while compounds 3-26 ( except 3, 8, and 17) showed notable activity against BChE. Compounds 17 (IC50: 3.22 ± 0.70 mM), 15 (IC50: 5.19 ± 0.03 mM), 24 (IC50: 7.21 ± 0.27 mM), 23 (IC50: 8.05 ± 0.11 mM), 14 (IC50: 8.10 ± 0.22 mM), 25 (IC50: 8.40 ± 0.64 mM), 26 (IC50: 8.76 ± 0.90 mM), and 22 (IC50: 9.13 ± 0.55 mM) produced higher tyrosinase inhibition activity. In urease inhibition activity, compounds 20 (IC50: 16.79 ± 0.19 μM), 19 (IC50: 18.25 ± 0.50 μM), 18 (IC50: 20.24 ± 0.77 μM), 26 (IC50: 21.51 ± 0.44 μM), 25 (IC50: 21.70 ± 0.06 μM), and 24 (IC50: 22.49 ± 0.11 μM) demonstrated excellent activities. Besides, the molecular docking study was applied to better understand the inhibitory mechanism between (1-26) compounds and enzymes at the molecular level. According to the results of this study, the synthesized compounds exhibited a better binding affinity toward these enzymes compared to the positive control. Further, molecular mechanics Poisson-Boltzmann surface area (MM/PBSA) binding free energy and molecular dynamics (MD) simulation analyses were performed for AChE with compound 26, which showed high inhibitory activity in silico and in vitro studies. In conclusion, novel morpholine and thiazolidine-based derivative compounds may be pharmacologically effective agents for AChE, BChE, tyrosinase, and urease enzymes.

LC-MS and NMR Based Plant Metabolomics: A Comprehensive Phytochemical Investigation of Symphytum anatolicum.

The application of metabolomics to the study of plants is growing because of the current development of analytical techniques. The most commonly used analytical technology driving plant metabolomics studies is Mass Spectrometry (MS) coupled to liquid chromatography (LC). In recent years, Nuclear Magnetic Resonance (NMR) spectroscopy, not requiring a previous chromatographic separation, has been receiving growing attention for metabolite fingerprinting of natural extracts. Herein, an integrated LC-MS and 1H NMR metabolomic approach provided a comprehensive phytochemical characterization of Symphytum anatolicum whole plant, taking into account both primary and specialized metabolites. Moreover, the NMR analyses provided direct quantitative information. Species belonging to the Symphytum genus, known as comfrey, have shown several biological activities including anti-inflammatory, analgesic, hepatoprotective, antifungal, and antibacterial. The LC-MS profile showed the presence of 21 main specialized metabolites, belonging to the classes of flavonoids, phenylpropanoids, salvianols, and oxylipins. The 1H NMR spectrum revealed the occurrence of metabolites including organic acids, phenolics, flavonoids, sugars, and amino acids. A quantitative analysis of these metabolites was performed and their concentration was obtained with respect to the known concentration of TSP, by means of the software package Chenomx which allows quantification of individual components in the NMR spectra. Furthermore, the phenolic content, antioxidant activity, glucosidase, and tyrosinase inhibitory activity of S. anatolicum extract were evaluated. The resulting bioactivity profile suggests how S. anatolicum represents a source of metabolites with health-promoting activity.

Chemical composition, antioxidant and anti-tyrosinase potentials of Acacia cyclops trunk bark using in vitro and in silico approaches

The purpose of this paper was to evaluate the phytochemical profile of Acacia cyclops trunk bark methanol extract using LC-MS/MS, as well as to assess its antioxidant and anti-tyrosinase activities. Thus, total phenolic and flavonoid contents of the studied extract were established and 19 compounds were detected and quantified. In addition of their antioxidant potential against DPPH and ABTS assays, in vitro and in silico studies were adopted to evaluate tyrosinase inhibitory property of A. cyclops extract. Methanol trunk bark extract showed significant total phenolic content, antioxidant potential in terms of free radical scavenging, as well as an interesting tyrosinase inhibitory action (IC50= 05.12 ± 0.41 μg/mL). The molecular docking analysis and the drug-likeness prediction of the major selected compounds supported the significant anti-tyrosinase activity of the studied extract. The obtained results suggest that A. cyclops extract could be a promising candidate in the treatment of skin hyperpigmentation disorders.

Anti-Browning Effect of 2-Mercaptobenzo[d]imidazole Analogs with Antioxidant Activity on Freshly-Cut Apple Slices and Their Highly Potent Tyrosinase Inhibitory Activity.

Ten 2-mercaptobenzimidazole (2-MBI) analogs were synthesized as potential tyrosinase inhibitors because mercapto-containing compounds can bind to copper ions at the active site of tyrosinase to inhibit enzyme activity. Nine 2-MBI analogs showed sub-micromolar IC50 values for mushroom tyrosinase monophenolase activity; analog 4 was 280-fold more potent than kojic acid, and in diphenolase activity, 6 was 970-fold more potent than kojic acid. The inhibition mode of the 2-MBI analogs was investigated using kinetic studies supported by docking simulations. Benzimidazoles without the 2-mercapto substituent of the 2-MBI analogs lost their tyrosinase inhibitory activity, implying that the 2-mercapto substituent plays an important role in tyrosinase inhibition. The 2-MBI analogs exerted potent antioxidant effects against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and reactive oxygen species (ROS). The results obtained from apple slices and human embryonic kidney cells (HEK-293) suggest that most 2-MBI analogs are sufficiently safe candidates to delay the browning of apple slices effectively. Thus, these results support the potential use of 2-MBI analogs as anti-browning agents in foods such as mushrooms, vegetables, and fruits.

Evaluation of Physiological Activity of Traditional Welsh Onion (Allium fistulosum L.)

Purpose: This study was conducted to evaluate physiological activities, such as antioxidant activity and enzyme activity, of hot water extract of the four parts (flower, leaf and pseudostem, stem, and root) of traditional Welsh onion (Allium fistulosum L.) and then to provide basic data on traditional Welsh onion to support future research.Methods: Four parts of traditional Welsh onion plant were extracted with water heated at 80℃. Antioxidative and enzymatic activities, such as total polyphenol content, total flavonoid content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azino-bis-3-ethylbenzothiazoline–6-sulfonic acid (ABTS) radical scavenging activity, and the inhibitory activity on α-glucosidase, tyrosinase, and elastase enzymes, were measured.Results: Out of the hot water extract of the different parts, Allium fistulosum flower (AFF) extract had the highest content of antioxidants. In the Allium fistulosum leaf and pseudostem (AFLP), Allium fistulosum stem (AFS), and Allium fistulosum root (AFR) extracts, the total polyphenol content and DPPH radical scavenging activity of the root were high, and AFS had high total flavonoid content and ABTS radical scavenging activity. Regarding enzyme activity, α-glucosidase and elastase inhibitory activities were the highest in AFR, and tyrosinase inhibitory activity was the highest in AFS.Conclusion: We confirmed the physiological activity of the hot water extract of four parts of traditional Welsh onion. Our findings provide basic data for research into traditional Welsh onion, and can facilitate its future development as a functional material.

Effects of Dietary Bacillus natto Productive Protein on the Skin: In Vitro Efficacy Test and Single-Armed Trial

The dietary bacillus natto productive protein (BNPP) is a functional food ingredient that contains Bacillopeptidase F. BNPP is reported to improve blood flow. Based on previous research, we investigated the effect of BNPP on the skin. In vitro tests were performed to evaluate BNPP for its inhibitory effects on tyrosinase, elastase, and active oxygen (2,2-diphenyl-1-picrylhydrazyl (DPPH)) radical scavenging activities. In addition, a small-scale, single-armed trial of 15 female participants aged 40–65 years were conducted to assess the effects on human skin of BNPP, administered 250 mg/day orally, for 6 weeks. The beneficial effects of BNPP on the skin were shown by the evaluation of the tyrosinase inhibitory (0.01% and 0.1%), elastase inhibitory (0.00001% to 0.001%), and DPPH radical scavenging (1% and 10%) activities. In addition, the results suggested that the oral administration of BNPP may significantly enhance skin rosiness and also achieve significant improvement in skin conditions, defined as complexion, skin elasticity and resilience, moist feeling, skin texture, cosmetic adhesion, fine lines, under-eye darkness, eye bags, sagging cheeks, and sagging mouth. Furthermore, to investigate the use of BNPP as cosmetics, a skin irritation study was conducted using a cultured human skin model. The results showed that BNPP is non-irritant. In addition, to confirm the stability of BNPP, the quality of BNPP at the time of manufacture and three years and six months after manufacture was examined. The results showed no quality problems. These results suggest that the BNPP could be used as cosmetic purposes.

자근 추출물의 항산화, 항균 및 미백효과에 관한 연구

To improve the utilization value of Lithospermum Root as a cosmetic material, the study investigated the antioxidant, antibacterial activity, intracellular tyrosinase activity, and melanin biosynthesis inhibitory effects of an Lithospermum Root ethanol extract. As a result, the antioxidant effect showed a 72.5% free radical scavenging at a concentration of 10,000 μg/ml, and the free radical scavenging (FSC)50 value was 4815.90 μg/ml. The antibacterial activity showed an inhibitory effect on all skin flora, S. epidermidis (9.3-14.6 mm), E. coli (10.7-14.6 mm), and P. acnes (9.5-15.2 mm). The viability of B16-F10 cells ranged from 104.9% to 110.1% up to a concentration of 1,000 μg/ml, and a whitening experiment was performed based on this result. At a concentration of 1,000 μg/ml, the intracellular tyrosinase activity inhibition rate was 37.28%, and the melanin synthesis inhibition rate was 30.09%. As a result, it was confirmed that the Lithospermum Root ethanol extract has a significant effect on antioxidant, antibacterial activity, and whitening, and thus has high utilization value as a functional whitening raw material for cosmetics. In the future, analysis of the physiologically active components of the ethanol extract of Lithospermum Root, verification of the efficacy of each component's whitening action, and mechanism studies will be considered necessary.

A comprehensive assessment of phytochemicals from Phyla nodiflora (L.) Greene as a potential enzyme inhibitor, and their biological potential: An in-silico, in-vivo, and in-vitro approach

This work explored Phyla nodiflora (L.) Greene as a potential source of the bioactive medicinal agent. In this aspect, methanol (PN-M) and dichloromethane (PN-D) extracts were prepared from the whole plant and evaluated for phytochemical composition (total bioactive contents, UHPLC-MS analysis, and HPLC-PDA polyphenolic quantification), biological (antioxidant and enzyme inhibition) potential and in-vivo toxicity. The PN-M was found to contain higher phenolic (26.08 mg GAE/g extract) and flavonoid (50.25 mg QE/g extract) contents which might correlate to the higher radical scavenging (DPPH: 52.94 mg TE/g extract; ABTS: 72.11 mg TE/g extract) and reducing power (FRAP: 71.96 mg TE/g extract; CUPRAC: 142.65 mg TE/g extract) antioxidant potential, as well as AChE (4.33 mg GALAE/g extract), tyrosinase (125.36 mg KAE/g extract), and amylase (1.86 mmol ACAE/g extract) inhibition activity of this extract. In contrast, the PN-D extract was found to be most active for phosphomolybdenum (1.30 mg TE/ g extract) and metal chelation (54.84 mg EDTAE/g extract) assays in addition to BChE (4.70 mg GALAE/g extract) and glucosidase (0.62 mmol ACAE/g extract) enzyme inhibition activity. The PN-M extract on UHPLC-MS analysis revealed the tentative identification of 24 different secondary metabolites, most of which belonged to the flavonoid, glycoside, and terpenoid classes of phytochemicals. The polyphenolic composition of the extracts was appraised by HPLC-PDA. Seven phenolic compounds were identified in the extracts. PN-M was found to be rich in catechin (0.25 µg/extract) and 3-OH benzoic acid (0.64 µg/extract), while PN-D contained epicatechin (0.30 µg/extract), 3-OH-4-MeO benzaldehyde (0.21 µg/extract), and 2,3-Di-Meo benzoic acid (0.97 µg/extract) in higher amounts. The methanol extract was found to be non-toxic even at higher doses. Furthermore, the relationship between the phytochemicals and the tested enzymes was highlighted by molecular docking studies. In sum, this research showed that the studied extracts were effective as enzyme inhibitors and antioxidants, suggesting it would be worth investigating in more depth for further advanced studies to explore its pharmacological properties.

Synthesis of naproxen thiadiazole urea hybrids and determination of their anti-melanoma, anti-migration, tyrosinase inhibitory activity, and molecular docking studies

Novel sixteen naproxen urea compounds were synthesized bearing the thiadiazole ring. Their inhibitory activities against tyrosinase were investigated. 3o was discovered to be the most potent inhibitor of tyrosinase, with an IC50 value of 35.0 µM. The kinetic parameters were used to determine the type of enzyme inhibition. The results showed that 3o was an uncompetitive inhibitor with the Ki value of 62.2 µM. Additionally, the cytotoxic effects of the synthesized compounds on melanoma (B16F10), mouse embryonic (3T3) and the healthy 3T3 cell lines were also investigated. According to the cytotoxicity results, 3e (IC50= 2.17 µM) showed the highest cytotoxicity on the B16F10 cells. Furthermore, the effects of selected compounds on the migration rate of melanoma cells were investigated. In addition, molecular modeling studies were also performed and the results showed the possible interactions between the uncompetitive inhibitor 3o with the Tyrosinase-L-Tyrosine enzyme substrate complex.

Borneol facilitates the whitening and anti-wrinkle effect of the essential oil extracted from Abies koreana needles

It has been reported that the essential oil extracted from Abies koreana has skin-improving activity, such as anti-wrinkle and whitening effect. However, the key ingredients that facilitate such biological activity has not been fully elucidated. In the present study, to identify the key skin-improving component(s) of the A. koreana essential oil, 10 sequentially fractioned essential oil from A. koreana pine by hydrodistillation were examined for their effect on tyrosinase activity. Out of 10 fractions, only 1 fraction significantly suppressed tyrosinase activity, and subsequent GC/MS analysis indicated that borneol and its acetate ester, bornyl acetate, were unique to the effective fraction, suggesting they are responsible for the skin-improving activity of the essential oil from A. koreana. The biological activity of borneol was evaluated, and borneol significantly inhibited ultraviolet irradiation-induced tyrosinase and matrix metalloproteinase 1 activity while maintain collagen type I synthesis. The results of this study suggest that borneol is a key component of A. koreana essential oil that has potential for mediating whitening and anti-wrinkle effects.