Tyrosinase Inhibition Assay Research Articles

PVP/CS/Phyllanthus emblica Nanofiber Membranes for Dry Facial Masks: Manufacturing Process and Evaluations.

In the wake of increasing demands on skin health, we propose simple, natural, and safe dry facial masks that restrict melanin synthesis. Phyllanthus emblica (P. emblica) is made into powders via a low-temperature extraction and freeze-drying process to serve as a natural agent. Next, it is added to mixtures containing Polyvinylpyrrolidone (PVP) and Chitosan (CS), after which the blends are electrospun into PVP/CS/P. emblica nanofiber membrane dry facial masks using the electrospinning technique. The dry facial masks are evaluated using the calibration analysis method, extraction rate test, scanning electron microscopy (SEM), release rate test, tyrosinase inhibition assay, biocompatibility test, and anti-inflammatory capacity test. Test results indicate that when the electrospinning mixture contains 29.0% P. emblica, the nanofibers have a diameter of ≤214.27 ± 74.51 nm and a water contact angle of 77.25 ± 2.21. P. emblica is completely released in twenty minutes, and the tyrosinase inhibition rate reaches 99.53 ± 0.45% and the cell activity ≥82.60 ± 1.30%. Moreover, the anti-inflammatory capacity test results suggest that dry facial masks confine inflammatory factors. PVP/CS/P. emblica nanofiber dry facial masks demonstrate excellent tyrosinase inhibition and are hydrophilic, biocompatible, and inflammation-free. The dry facial masks are a suitable material that is worthwhile exploring and applying to the cosmetic field.

Development of Sunscreen Containing Alpha-Mangostin Riched Extract with Anti-Tyrosinase Activities

Abstract This study focused on the development of extracts from mangosteen rinds for use as whitening and sunscreen agents. Mangosteen rinds were obtained from 9 locations in the East and the South of Thailand. Ethanol (95%) crude rind extracts were prepared and separated by column chromatography. The fractions were collected from top (F1-F4) and mid spots (F12-F15). These fractions were subjected to tyrosinase inhibitory activity assay and found that the top spot exhibited low activity with IC50 > 100 µg/mL while the mid spots inhibited tyrosinase enzyme at IC50 18.48 µg/mL which is more sensitive than a positive control, kojic acid (38.46 µg/mL). The mid spots fraction from the crude extract of Chanthaburi sample 1 was analyzed with HPLC and was assigned as MGS-1 extract which contained a high amount of α-mangostin. MGS-1 extract was formulated as oil in water cream with 2, 4, 6, and 9 %w/w extract. All creams were subjected to measure SPF and UVA/UVB ratio using an Optometrics SPF-290S analyzer. It was found that the cream with 6 %w/w MGS-1 extract showed the best results with SPF at 10.36 ± 1.07 and had a UVA/UVB ratio equal to 0.451. These sunscreen properties are close to the properties of Salisol-3 (benzophenone), a standard sunscreen. In conclusion, MGS-1 extract has a good potential to be used as a whitening and sunscreen agent in cosmetics with a lower cost of substrate because mangosteen rinds can be found as waste from eating mangosteen fruit every year in Thailand. Keywords: Mangosteen rind, MGS-1 extract, Tyrosinase inhibition, Whitening agent, Sunscreen

A Strategy for Pinpointing Natural Bioactive Components Using Two-Dimensional Bioassay Profilings Combined with Comprehensive Two-Dimensional Countercurrent Chromatography × High-Performance Liquid Chromatography.

Inspired by the interpretation of two-dimensional (2D) nuclear magnetic resonance spectra, an efficient strategy was proposed for pinpointing bioactive components from complex natural products. An off-line comprehensive countercurrent chromatography (CCC) × high-performance liquid chromatography (HPLC) was employed to achieve a 2D chemical chromatogram, and 2D bioassay profilings were obtained from bioassays of the eluent of the first dimension (1D) CCC and the eluent of the second dimension (2D) HPLC. Then 2D chemical chromatograms and 2D bioassay profilings were matched for pinpointing bioactive natural components from complex matrices. Thus, bioactive components in a complex matrix could be efficiently analyzed, separated, and bioactivity-determined. This experimental scheme was successfully demonstrated with a traditional medicinal herb Polygonum cuspidatum Sieb. et Zucc. The feasibility of this 2D strategy was verified with tyrosinase inhibition assay, α-glucosidase inhibition assay, DPPH radical scavenging assay, and ABTS•+ decolorization assay. Eight natural inhibitors were successfully pinpointed and identified from P. cuspidatum. Both pieceid-2″-O-gallate (10) and vanicoside B (20) were screened and identified as natural tyrosinase inhibitors for the first time. Meanwhile, vanicoside B (20) was also found as the strongest α-glucosidase inhibitor among all the isolated components. Most of the compounds exhibited much higher radical scavenging activities. Compared with traditional methodology based on one-dimensional chromatographic separation, the present 2D strategy would be more precise, efficient, and convenient to screen and separate bioactive compounds from complex matrices.

Development of Phytocosmeceutical Microemulgel Containing Flaxseed Extract and Its In Vitro and In Vivo Characterization.

Antioxidants from natural sources are extensively attaining consideration to avert the skin from damage and aging caused by free radicals. Flaxseed (Linum usitatissimum L.), a natural therapeutic agent, was meant to be explored cosmeceutical by quantifying its potential phytoconstituents and to be incorporated into a microemulgel for topical use. Hydroalcoholic fractions (both methanolic and ethanolic; 80%) flaxseed extracts were subjected to phytochemical screening by quantifying total phenolic content (TPC), total flavonoid content (TFC), and high-performance liquid chromatography-ultraviolet (HPLC-UV), and for biological activities through 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, tyrosinase inhibition assay, and sun protection factor (SPF). Ethanolic fraction was selected for further study by TPC (18.75 mg gallic acid equivalent/g) and TFC (1.34 mg quercetin equivalent/g). HPLC-UV analysis showed the existence of benzoic, quercetin, caffeic, vanillic, p-coumaric, gallic, cinnamic, syringic, and sinapic acids. Biological activities showed 87.00%, 72.00%, and 21.75 values for DPPH assay, tyrosinase inhibition, and SPF assays, respectively. An oil-in-water (OW) microemulsion containing the flaxseed extract, with 99.20 nm Zeta size, −19.3 Zeta potential and 0.434 polydispersity index was developed and incorporated in Carbopol-940 gel matrix to formulate an active microemulgel with 59.15% release in in vitro studies. The successfully formulated stable active microemulgel produced statistically significant effects (p < 0.05), in comparison to a placebo, on skin erythema, melanin, sebum, moisture, and elasticity, in a noninvasive in vivo study performed on 13 healthy human female volunteers. Other cosmeceutical products can also be formulated from flaxseed, making it a considerable candidate for further utilization in the pharmaceutical industry.

Exploring the industrial importance of a miracle herb Withania somnifera (L.) Dunal: Authentication through chemical profiling, in vitro studies and computational analyses

Withania somnifera (L.) Dunal has been identified as a miracle herb, thus the present study was carried out to investigate W. somnifera growing in Cholistan Desert for its secondary metabolic profile and various biological activities. The WS-C fraction of methanolic extract (WS-M) of W. somnifera was found rich in phenolics (39.96 ± 0.90 mg GAE/g extract), and it exhibited significant DPPH (30.69 ± 0.78 mg TE/g extract) and ABTS (113.60 ± 2.41 mg TE/g extract) free radical inhibitory activities, cupric (Cu+2) and ferric (Fe+3) reducing potential as 157.51 ± 2.10 and 124.60 ± 0.34 mg TE/g extract. The same fraction also exhibited strong total antioxidant capacity (1.39 ± 0.01 mmol TE/g extract) in phosphomolybdenum assay. Other fractions displayed relatively lower potential. In metal-chelating assay, WS-M, WS-E and WS-B showed nearly equal potential with values of 22.35 ± 0.62, 20.96 ± 0.12 and 22.10 ± 0.75 mg EDTAE/g of the extract, while in AChE, BChE and tyrosinase inhibitory assay, again WS-C fraction was most active (7.50 ± 0.21, 8.01 ± 0.53 mg GALAE/g extract and 36.81 ± 0.20 mg KAE/g extract, respectively). In α-amylase and α-glucosidase inhibitory assay, WS-C showed significant potential with values as 0.74 ± 0.01 and 1.14 ± 0.004 mmol ACAE/g extract, respectively. UHPLC-MS analysis of WS-C fraction leads to identify 100 secondary metabolites of phenolic, withanolide, terpenoid, steroid, lignin, flavonoid and limonoid classes of compounds. This profile makes W. somnifera a fascinating plant. These findings were validated by computational studies, which revealed that selected compounds exhibited high binding free energy and inhibition constants with the enzymes tested. Pearson correlation analysis clearly established that the phenols in the tested extracts were the main players as antioxidants and enzyme inhibitors, which was also substantiated through Principal Component Analysis (PCA). These results suggest that chloroform might be suitable for preparing further applications with W. somnifera extracts, and this plant can be placed in the list of top-selling herbs, and may become source of commercial assets.

Discovery of Novel Tyrosinase Inhibitors From Marine Cyanobacteria.

Tyrosinase, an important oxidase involved in the primary immune response in humans, can sometimes become problematic as it can catalyze undesirable oxidation reactions. Therefore, for decades there has been a strong pharmaceutical interest in the discovery of novel inhibitors of this enzyme. Recent studies have also indicated that tyrosinase inhibitors can potentially be used in the treatment of melanoma cancer. Over the years, many new tyrosinase inhibitors have been discovered from various natural sources; however, marine natural products (MNPs) have contributed only a small number of promising candidates. Therefore, in this study we focused on the discovery of new MNP tyrosinase inhibitors of marine cyanobacterial and algal origins. A colorimetric tyrosinase inhibitory assay was used to screen over 4,500 marine extracts against mushroom tyrosinase (A. bisporus). Our results revealed that scytonemin monomer (ScyM), a pure compound from our compound library and also the monomeric last-step precursor in the biosynthesis of the well-known cyanobacterial sunscreen pigment “scytonemin,” consistently showed the highest tyrosinase inhibitory score. Determination of the half maximal inhibitory concentration (IC50) further indicated that ScyM is more potent than the commonly used commercial inhibitor standard “kojic acid” (KA; IC50 of ScyM: 4.90 μM vs. IC50 of KA: 11.31 μM). After a scaled-up chemical synthesis of ScyM as well as its O-methyl analog (ScyM-OMe), we conducted a series of follow-up studies on their structures, inhibitory properties, and mode of inhibition. Our results supported ScyM as the second case ever of a novel tyrosinase inhibitory compound based on a marine cyanobacterial natural product. The excellent in vitro performance of ScyM makes it a promising candidate for applications such as a skin-whitening agent or an adjuvant therapy for melanoma cancer treatment.

Quality Assessment of Apple and Grape Juices from Serbian and German Markets by Planar Chromatography-Chemometrics.

The high consumption of plant-based foods on a global scale has increased the number of adulterations in the food industry. Along with this, analytical approaches to fraud detection need to be further developed. A nontargeted effect-directed profiling by high-performance thin-layer chromatography hyphenated with five effect-directed assays (free radical scavenging assay, Aliivibrio fischeri bioassay, and acetylcholinesterase, butyrylcholinesterase, and tyrosinase inhibition assays) and multi-imaging provided additional information on the antioxidative, antimicrobial, and enzyme inhibition activities for 18 apple and 18 grape juices from markets in Serbia and Germany. Bioactive zones of interest were eluted using an elution head-based interface and further characterized by electrospray ionization high-resolution mass spectrometry. The different profiles were evaluated chemometrically, and several compounds, which were characteristic of samples from different markets located in Serbia and Germany, were identified in apple juice (such as chlorogenic acid, phloridzin, epicatechin, and caffeic acid) and grape juice (such as chlorogenic acid, epicatechin, and quercetin). The developed rapid and simple method for the quality assessment of fruit juices coming from different (geographic) markets showed clear quality differences. Thus, it could be used to learn more about quality differences, to detect fraud in fruit juice production, and to verify the authenticity of the origin.

Ziziphus lotus (L.) Lam. as a Source of Health Promoting Products: Metabolomic Profile, Antioxidant and Tyrosinase Inhibitory Activities.

The methanolic extract of the stem bark of a wild species of jujube, Ziziphus lotus (L.) Lam., growing in Sicily, was chemically and biologically investigated. The chemical profile was defined by UHPLC-HR-ESI-Orbitrap/MS analysis whereas antioxidant and tyrosinase inhibitory activities were investigated by in vitro assays. The extract showed a high total phenolic and flavonoid content (TPC=271.65 GAE/g and TFC=188.11 RE/g extract). Metabolomic analysis revealed a rich phytocomplex characterized by phenols, cyclopeptide alkaloids, and triterpenoid saponins, some of which here detected for the first time. The mushroom tyrosinase inhibition assay displayed that the methanolic extract efficiently inhibits the monophenolase and diphenolase activity. Furthermore, the extract showed a strong ability to scavenge DPPH, a good Fe3+ reducing antioxidant power, in addition to a Fe2+ chelating activity. Taken together, these results suggest possible novel applications of wild jujube stem bark as a source of potential skin-care agents with several uses in pharmaceutical and cosmetic industries.

Development, characterization, and clinical investigation of Spinacia oleracea-based ultra-high pressure homogenized emulsion system for facial physiological parameters.

Spinacia oleracea (SO) exhibits radical scavenging and tyrosinase inhibition activity indicating potential as a depigmenting agent. To develop and characterize a stable emulsified system containing SO extract through ultra-high pressure homogenization, evaluate skin permeability, and enumerate in vivo performance in terms of melanin index, skin spots analysis, and related skin physiological parameters. Free radical scavenging and tyrosinase inhibition potential of SO extract was quantified through DPPH radical scavenging and mushroom tyrosinase inhibition assay, respectively. Six SO extract loaded ultra-high pressure emulsified systems (UHSO) were developed using ultra-high pressure homogenizer and assessed for size and polydispersity index (PDI). Among the prepared formulations, the optimized formulation (UHSO6) was subjected to 90days stability studies performed at 8°C, 25°C, 40°C, and 40°C+75% RH (relative humidity) for organoleptic features, pH, and rheology. Ex vivo skin permeability studies were performed on abdominal skin from male albino rat. Changes in skin physiological parameters were evaluated in healthy female volunteers (n=13) for 12weeks utilizing mexameter® , corneometer® , and sebumeter® . Skin spots were analyzed through computerized analysis of high-resolution images by visioFace® . SO extract exhibited promising antioxidant (88±0.0096%) and tyrosinase inhibition potential (90.6±0.0015mg of Kojic Acid Eq/g of extract). Optimized UHSO was found to be stable with respect to stability evaluation, globule size (1110nm), zeta potential (-27.6), and PDI (0.34). Ex vivo skin permeation of UHSO was significantly higher than SO loaded coarse emulsion. Moreover, the formulation showed a significant decrease in skin melanin, spot count, and spot % area, whereas skin hydration index was improved significantly. Stable SO extract loaded emulsion system was successfully developed by a novel, cost-effective technique of ultra-high pressure homogenization which showed improved performance in terms of skin permeation and other skin physiological parameters.

Formulation and Physicochemical Evaluation of Green Cosmeceutical Herbal Face Cream Containing Standardized Mangosteen Peel Extract

The widely reported adverse effects of synthetic ingredients encourage the development of green cosmeceuticals to achieve Sustainable Development Goal (SDG) 3. The waste product of mangosteen (mangosteen peel) was utilized in the formulation to reduce waste production corresponding to SDG 12, in addition to its anti-aging and pigmentation control effects. This study aimed to formulate and evaluate novel herbal face creams containing standardized mangosteen peel extract. The mangosteen creams were formulated using natural ingredients and were evaluated for their organoleptic characteristics, rheology, spreadability and pH. Furthermore, an accelerated stability study, freeze–thaw stability study and centrifugation test were conducted. In addition, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assays were conducted to assess its antioxidant effects, whereas tyrosinase inhibitory assay was conducted to determine its anti-tyrosinase activity. The formulated creams appeared light yellowish-brown and homogenous without phase separation. The creams displayed shear-thinning behavior and optimal pH which was ideal for topical application. The creams were stable after being subjected to various stability tests and were shown to have antioxidant and anti-tyrosinase activity. In conclusion, the development of mangosteen-based green cosmeceutical face cream is in line with SDG 3 and 12. It is expected to be used as a safe and effective alternative to synthetic products.

Tyrosinase Inhibitory Activity of Extracts from Prunus persica

The demand for skin-whitening agents is high across the world, including Asian countries. An extensive screening using a tyrosinase inhibition assay was performed in order to discover novel plant materials. In our research program investigating a safe and effective agent, 50% ethanolic extracts prepared from discarded parts of Prunus persica were screened for in vitro tyrosinase inhibitory activity. Among the extracts tested, twig extract showed the most potent inhibitory activity: 38% inhibition at 500 µg/mL. The investigation of active compounds in twig extract found four flavanones that acted as moderate inhibitors, including (−)-prunin, persiconin, (+)-dihydrokaempferol, and (−)-naringenin. These compounds were only observed in the twig extract following preliminary quantification by HPLC, with the following concentrations: (−)-prunin, 1.8 mg/g sample; persiconin, 0.8 mg/g sample; (+)-dihydrokaempferol, 0.8 mg/g sample; (−)-naringenin, 1.7 mg/g sample. These results suggest that twig extracts can be more useful for skin-whitening compared with other parts of the plant. In addition, a new constituent of twig extract was identified, namely isoquercitrin, which suggests that twig extract can be a potent source of flavones and flavanones. Further studies on the identification of novel compounds from twig extract are now underway in our laboratory.

Hop Tannins as Multifunctional Tyrosinase Inhibitor: Structure Characterization, Inhibition Activity, and Mechanism.

The application of hops could be extended to obtain higher commercial values. Tannins from hops were assessed for their tyrosinase inhibition ability, and the associated mechanisms were explored. Nuclear magnetic resonance (NMR) and high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC–ESI–MS/MS) revealed that the hop tannins were characterized as condensed tannins with (epi)catechin and (epi)gallocatechin as subunits and an average polymerization degree of 10.32. Tyrosinase inhibition assay indicated that hop tannins had an IC50 = 76.52 ± 6.56 μM. Kinetic studies of the inhibition processes indicated the tannins provided inhibition through competitive–uncompetitive mixed reactions. In silico molecule docking showed that tannins were bound to the active site of tyrosinase via hydrogen and electrovalent bonds. Circular dichroism (CD) observed the structural variation in the tyrosinase after reacting with the tannins. Fluorescence quenching analysis and free radical scavenging assays indicated that the tannins had copper ion chelating and antioxidant activities, which may also contribute to inhibition. The intracellular inhibition assay revealed that the melanin was reduced by 34.50% in B16F10 cells. These results indicate that these tannins can be applied as whitening agents in the cosmetics industry.

Synthesis and molecular modeling of new 2‐benzylidenethiobarbituric acid derivatives as potent tyrosinase inhibitors agents

AbstractNew 2‐benzylidenethiobarbituric acid‐(benzyloxyphenyl) derivatives were designed, synthesized, and evaluated as tyrosinase inhibitors. The products can be divided into two groups: 4‐hydroxybenzaldehyde derivatives and vanillin derivatives. Some of the 4‐hydroxybenzaldehyde derivatives showed significant inhibitory activity while all vanillin derivatives have no inhibitory activities. It seems that the presence of the methoxy group on the internal aromatic ring prevents the ligand–enzyme interaction. According to the tyrosinase inhibitory assay, 5‐(4‐([4‐Methylbenzyl]oxy)benzylidene)‐2‐thioxodihydropyrimidine‐4,6(1H,5H)‐dione (4g) is the most potent antityrosinase agents with an IC50 value of 23.90 ± 0.08 μM. It showed even better inhibitory activity than kojic acid. The results of kinetic and molecular docking studies demonstrated that compound 4g acts as a noncompetitive inhibitor and can bind to some amino acids such as His263 and Val283 of the active site through Pi–alkyl and Pi–Pi interactions and areas around the active site via the hydrogen bond. In‐silico adsorption, distribution, metabolism, excretion, and toxicity (ADMET) studies predicted that these products have good drug‐likeness. All findings indicate the 2‐benzylidenethiobarbituric acids with the benzyloxyphenyl tail have good potential for the treatment of melanogenesis compared to kojic acid.

Chemodiversity, Biological Activities and Molecular Docking Studies of Leptadenia pyrotechnica (Forssk.) Decne: A Comprehensive Approach to Validate Its Medicinal Use.

Leptadenia pyrotechnica (Forssk.) Decne is growing in Cholistan desert, and is known for its laxative, analgesic, anabolic and astringent, antioxidant, anti-inflammatory, antibacterial, antitumor, hypolipidemic and antiatherosclerotic properties. The present study disclosed the metabolic picture of L. pyrotechnica and validates its folk uses. LP-H fraction constitute 25.79±0.11 mgGAE/g extract and 20.64±0.33 mgRE/g extract of phenolic and flavonoid content, respectively, followed by LP-E (23.15±0.33 mgGAE/g extract and 19.40±0.13 mgRE/g extract), however, LP-E exhibited the highest free radical scavenging (DPPH: 21.05±0.45mgTE/g and ABTS: 68.12±0.53 mgTE/g) and metal reducing (FRAP: 44.93±1.66, CUPRAC: 117.42±1.28 mgTE/g, respectively) activities. The total antioxidant capacity in Phosphomolybdenum assay (1.52±0.14 mmolTE/g) and ferrous ion chelating (11.57±0.29 mgEDTAE/g) activities were observed highest for LP-H extract. In cholinesterase's inhibitory assays, the LP-E and LP-W extracts exhibited inhibitory values as 2.43 and 2.40±0.07 mgGALAE/g extract, respectively against AChE, while against BChE the LP-H displayed the highest value as 5.98±0.44 mgGALAE/g extract. The LP-H fraction also showed the highest inhibition potential (7.72±0.14 mmol ACAE/g and 0.55±0.01 mmol ACAE/g, respectively) against α-glucosidase and α-amylase enzymes, while, in tyrosinase inhibitory assay, all the fractions exhibited significant activities in the range of 59.35±0.29 to 55.18±0.49 mgKAE/g extract. RP-UHPLC/MS analysis of LP-M disclosed the presence of 57 metabolites of various classes. A multivariate analysis and molecular docking study was also carried out to establish relationships between the metabolites and the biological activities, which finally validate the use of L. pyrotechnica as herbal medicine or component nutraceutical, food and cosmetic industry.

Schisandra rubriflora Fruit and Leaves as Promising New Materials of High Biological Potential: Lignan Profiling and Effect-Directed Analysis.

The effect-directed detection (EDD) of Schisandra rubriflora fruit and leaves extracts was performed to assess their pharmacological properties. The EDD comprised TLC—direct bioautography against Bacillus subtilis, a DPPH assay, as well as α-glucosidase, lipase, tyrosinase, and acetylcholinesterase (AChE) inhibition assays. The leaf extracts showed stronger antioxidant activity than the fruit extract as well as inhibition of tyrosinase and lipase. The fruit extract was found to be extremely active against B. subtilis and to inhibit α-glucosidase and AChE slightly more than the leaf extracts. UHPLC–MS/MS analysis was carried out for the bioactive fractions and pointed to the possible anti-dementia properties of the dibenzocyclooctadiene lignans found in the upper TLC fractions. Gomisin N (518 mg/100 g DW), schisanhenol (454 mg/100 g DW), gomisin G (197 mg/100 g DW), schisandrin A (167 mg/100 g DW), and gomisin O (150 mg/100 g DW) were the quantitatively dominant compounds in the fruit extract. In total, twenty-one lignans were found in the bioactive fractions.

Skin Whitening and Anti-wrinkle Effects of Chambirum (Amaranthus mangostanus)

Purpose: To investigate the cosmetic effects of a chambirum (Amaranthus mangostamus) extract on the skincare by measuring the extract’s antioxidant, anti-wrinkle, and whitening.Methods: To confirm the antioxidant effect of chambirum, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and superoxide dismutase (SOD)-like activity was determined. To confirm whitening effect of chambirum, tyrosinase inhibitory activity and melanin content were investigated. To confirm anti-wrinkle effect of chambirum, the elastase inhibition effect and type I procollagen production was assayed. B16F10 mouse melanoma cells and CCD986sk human dermal fibroblast cells were used to assay cell viability.Results: The DPPH radical scavenging activity of Amaranthus mangostanus ethanol extracts (AME) and Amaranthus mangostanus water extracts (AMW) was 49% and 56%, respectively, at 500 μg/mL. The SOD-like activity of AME and AMW was 67% and 57%, respectively, compared with that of the standard sample L-ascorbic acid at 38% at 1 mM. AME showed 25.9% (L-tyrosine) and 17.8% (L-DOPA), and AMW showed 23.4% (L-tyrosine) and 18.5% (L-DOPA) of tyrosinase inhibition assay. In addition, the intracellular melanin production in B16F10 mouse melanoma cells was decreased by AME and AMW by 25.5% and 24.0%, respectively. Additionally, the elastase inhibition assay results demonstrated inhibition by AME (19.7%) and AMW (17.2%) at 500 μg/mL and the amount of type I procollagen was shown to be insignificant. Furthermore, B16F10 mouse melanoma cells were 76% and 86% showed a viability 76% and 86% when treated with 100 μg/mL AME and AMW, respectively. CCD986sk fibroblast cells showed a viability 94.5% and 83.6% when we treated with 100 μg/mL AME and AMW, respectively.Conclusion: These results suggest that the chambirum (Amaranthus mangostamus) extract has excellent anti-oxidants, anti-wrinkle, and whitening effects. Therefore, it may have a significant industrial value as a functional material for cosmetic or anti-aging related bioproducts.

Isolation of bioactive compounds with tyrosinase inhibitory activity from the methanol extract of meniran herb (Phyllanthus niruri Linn.)

Meniran (Phyllanthus niruri L.) is a wild plant in the Euphorbiaceae family which grows in tropical climates. The plant is known to possess antioxidant activity and is rich in phenolic compounds. Since plants with high phenolic content and high antioxidant activity are known to exhibit high tyrosinase inhibitory activity, the purpose of this study is to determine the inhibitory activity of the tyrosinase enzyme by the methanol extract of meniran (P. niruri L.) and to isolate secondary metabolites from the extract and fractions which exhibit inhibitory activity against tyrosinase. The in vitro tyrosinase inhibitory activity assay was conducted using the 96-well microplate method with kojic acid as the positive control, while the separation and purification of compounds were carried out using chromatography techniques. The methanol extract and n-hexane fraction showed tyrosinase inhibitory activity with IC50 of 11.05±0.16 and 2.57±0.08 mg/ml, respectively. Three bioactive compounds were succesfully isolated from the n-hexane fraction. Based on the UV and NMR spectra, compounds 1, 2, and 3 were identified as phyllanthin, phyltetralin, and hypophyllanthin, respectively. Furthermore, phyllanthin (1) was shown to demonstrate inhibitory activity against tyrosinase with IC50 of 0.6322 mM. In conclusion, both meniran extract and phyllanthin (1) were found to exhibit inhibitory acitivity against the tyrosinase enzyme. In the future they can be candidates for the treatment against hyperpigmentation and also as an active ingredient in skincare formulations.

Plants from Urban Parks as Valuable Cosmetic Ingredients: Green Extraction, Chemical Composition and Activity

The research on the possibilities of using biowaste from urban green areas is scarce. In this work, four plants, widely distributed in urban parks in Central Europe (Lotus corniculatus, Medicago lupulina, Knautia arvensis and Plantago major) were extracted using eco-friendly solvents based either on aqueous cyclodextrin solutions (hydroxypropyl-β-cyclodextrin or γ-cyclodextrin) or natural deep eutectic solvents based on glycerol, betaine and glucose. Metal content was determined using total reflection X-ray fluorescence (TXRF). The content of selected metabolites was determined using UV-VIS spectrophotometric methods and HPLC. Skin-related bioactivity was assessed using tyrosinase and elastase inhibition assays. The selected plants contained metals beneficial for skin health, such as zinc and calcium, while having a low content of toxic heavy metals. The extracts contained the bioactive phenolics such as quercetin, kaempferol, luteolin and apigenin. L. corniculatus was the most potent tyrosinase inhibitor, while K. arvensis showed the most pronounced elastase inhibitory activity. The employed solvents actively contributed to the observed bioactivity. The results indicate that the biowaste obtained from urban parks represents an ecologically acceptable alternative to conventional cultivation for the preparation of ecologically acceptable, high-value cosmetic products.

Flavone-based hydrazones as new tyrosinase inhibitors: Synthetic imines with emerging biological potential, SAR, molecular docking and drug-likeness studies

Targeting tyrosinase (TYR), a key enzyme responsible for melanogenesis disorders, is a well-known approach utilized for the development of melanogenesis inhibitor. A variety of dermatological disorders and microbial skin infections can cause hyperpigmentation. Hence, exploring new scaffolds for the treatment of melanogenesis disease is an inspiring goal. In this context, a series of varyingly substituted flavone-based hydrazones have been designed, synthesized and characterized successfully. The present study describes the discovery of novel mushroom tyrosinase inhibitors (TIs) for treating hyperpigmentation. In due course, flavone scaffold has been incorporated into the novel chemotypes that exhibit in vitro inhibitory effects against mushroom tyrosinase for the purpose of discovering anti‐melanogenic agents. Biological investigations of prepared analogs herein demonstrated moderate to excellent activity against most of the fungal-bacterial strains and their activity is comparable to those of commercially available antibiotics i.e., Ciprofloxacin and Ketoconazole. Based on in vitro tyrosinase inhibitory assay, some compounds exhibited potent inhibition particularly, 3g (IC50 = 1.40 ± 0.16 µM), 3j (IC50 = 0.95 ± 0.07 µM), 3o (IC50 = 1.13 ± 0.11 µM), and 3q (IC50 = 1.01 ± 0.1 µM) showed best inhibition i.e., 0.7, 0.5, 0.6 and 0.5 folds, respectively, than kojic acid (IC50 = 1.79 ± 0.6 µM). Lineweaver-Burk plots demonstrated that the most potential derivative 3j tyrosinase inhibition proceeds via non-competitive pathway and the Michaelis-Menton constant (Km) value is 0.0265. Molecular modeling was performed for all tested analogs (3a–3q) using a model of mushroom tyrosinase to find crucial binding modes liable for inhibitory activity. The SARs were preliminarily examined, and the docking study revealed that analogs 3j, 3o and 3p had a strong binding association to tyrosinase (2Y9X). Furthermore, a drug-likeness study was employed and confirmed the favorable activity of the new analogs as a new anti-tyrosinase agent.

Phenolic Content, Antioxidant Properties, Key Enzyme Inhibitory Potential and Photoprotective Activity of Lawsonia inermis L.

Background: Lawsonia inermis Linn (Lythraceae), commonly known as "Henna" is a medicinal plant widely used as a folk remedy and for its cosmetic properties. Objective: The objective of this present work was to evaluate biological activities and to quantify phenolics in extracts. Methods: The extracts were obtained from seeds of L. inermis by increasing the polarity of the solvent. The content of total phenolics, flavonoids, flavonols and tannins was determined using colorimetric methods. Also, to evaluate the antioxidant activity, six different assays, DPPH, ABTS, superoxide radical scavenging, inhibition of β-carotene bleaching, ferric reducing antioxidant power and phenanthroline assays were used. Enzyme inhibition activity was evaluated by acetylcholinesterase, butyrylcholinesterase and tyrosinase inhibition assays. Furthermore, photoprotective activity was determined by measuring sun protection factor. Results: The extraction efficiency of phenolics, as well as the biological activities of plant extracts, were affected by solvent polarity. The highest content of phenolics was determined in methanol extract (786.54 ± 0.00 mg GAEg-1 DW), followed by the aqueous and ethyl acetate extracts (526.48 ± 0.40 and 331.25 ± 0.00 GAEg-1 DW, respectively).The above extracts also exhibited the highest antioxidant activity, while low polar extracts were characterized with the lowest content of phenolics, as well as the lowest antioxidant capacity. The highest enzyme inhibition activities were found in ethyl acetate extract. Moreover, the methanol extract showed the best photoprotective activity with sun protection factor of 43.05 ± 0.37. Conclusion: These findings suggest a possible use of Henna seeds as a potential source of bioactive molecules with antioxidant, enzyme inhibition and skin protection properties.