Tyrosinase Enzyme Inhibition Research Articles

Investigating the inhibitory effects of carotenoids-fortified Helix aspersa slime on oxidative stress, collagenase and tyrosinase enzyme activities.

The investigations of snail slime and its possible biological activities have been performed recently. This study aimed to evaluate the properties of Helix aspersa snail slime (HAS), and carotenoids-fortified slime (HASC). Snails were fed with carrots for 10 days. Slime was collected and extracted using water. Saponins identification, antioxidant, collagenase, and tyrosinase enzyme inhibition activities, carotenoids, total phenols, and flavonoids content, were determined. UHPLC-MS/MS analysis was performed for phytochemical characterization. Saponins were detected in the HAS extract only. However, HASC was shown to contain a higher carotenoid content than HAS (29.51 ± 0.4 vs. 18.11 ± 0.2 μg/g). similarly, total phenolic and flavonoid content were higher for the the HASC extract compared to the HAS (182.3 ± 5.2 vs. 150.28 ± 3.3 mg/g equivalent to gallic acid), and (77.62 ± 1.2 vs. 14.19 ± 0.9 mg/g equivalent to quercetin). As expected, the HASC extract exhibited higher antioxidant activity compared to the HAS, using DPPH and the ABTS assays (IC50 = 7.75 ± 0.14 vs. 20.1 ± 0.4 μg/mL), and (IC50 = 7.6 ± 0.26 vs. 19.57 ± 1.4 μg/mL). UHPLC-MS/MS analysis revealed the presence of several phytocomponents of which, hexadecanoic acid and ascorbic acid, were observed in the HASC extract. Furthermore, HASC extract exhibited superior inhibitory activity compared to HAS against collagenase and tyrosinase enzymes (IC50 = 8.4 ± 1.19 vs. 15.3 ± 1.12 μg/mL) and (IC50 = 30.1 ± 0.91 vs. 35 ± 1.3 μg/mL). These findings highlight the potential of HASC as a valuable ingredient in various pharmaceutical applications, due to their content of various phenolic, antioxidants, carotenoids, hexadecanoic, and ascorbic acids. The latter is well known for its great cosmeceutical applications used for slowing the process of skin aging.

ESSENTIAL OIL CONTENTS AND BIOLOGICAL ACTIVITIES OF THYMUS CANOVIRIDIS JALAS AND THYMUS SIPYLEUS BOISS.

Objective: Members of the Lamiaceae family are considered to be major sources of bioactive therapeutic agents. Many of them are important medicinal and aromatic plants used in traditional and modern medicine and in the food, cosmetic and pharmaceutical industries. The aim of this study was to investigate in detail the biological activities and chemical composition of the essential oils of Thymus canoviridis Jalas and Thymus sipyleus Boiss. species belonging to the genus Thymus, one of the most important genera of the Lamiaceae family. Material and Method: The essential oil content of the species was determined by GC-MS. Antioxidant activities of the essential oils were determined using lipid peroxidation, DPPH free radical, ABTS cation radical and CUPRAC methods. In addition, cytotoxic activities against breast cancer (MCF-7) and colon cancer (HT-29) cell lines and anticholinesterase (against AChE and BChE enzymes), urease, tyrosinase, elastase, collagenase and angiotensin converting enzyme inhibition activities were determined. Result and Discussion: When the essential oil composition of T. sipyleus was analyzed, the major compounds were 1,8-cineole (eucalyptol) (18.16%), camphor (15.08%) and endo-borneol (11.63%), while T. canoviridis was found to be rich in carvacrol (72.88%). T. canoviridis showed high antioxidant activity in lipid peroxidation (IC50: 45.72±0.12 μg/ml), ABTS (IC50: 6.12±0.03 μg/ml) and CUPRAC (IC50: 5.31±0.01 μg/ml) methods. The selectivities of T. canoviridis and T. sipyleus species against MCF-7 cell line were 4.39 and 6.81, respectively. In the enzyme inhibition studies, both Thymus species showed moderate inhibition activity against BChE enzyme (Inhibition%: 57.88±1.14, 39.21±0.89, respectively). In addition, T. sipyleus showed moderate inhibition of elastase enzyme (Inhibition%: 25.33±0.79). When the results are evaluated in general, it can be said that T. canoviridis essential oil with its rich carvacrol content and high cytotoxic and antioxidant activity can be preferred as a safer and natural option instead of synthetic preservatives in food, pharmaceutical and cosmetic industries to extend shelf life and ensure food safety.

The Potency of Adenostemma platyphyllum as Antimelanogenic Agent: In-vitro and In-silico Studies

Melanin is a crucial amino acid in determining human skin and hair pigmentation. Excessive melanin production can lead to hyperpigmentation and darkening of the skin. This study aims to assess the capability of Adenostemma platyphyllum as a tyrosinase enzyme inhibitor. It predicts its anti-melanogenic activity through molecular docking with proteins involved in the melanogenesis process. The in-vitro approach was conducted by determining the tyrosinase enzyme inhibition capacity, while the in-silico approach involved ligand binding to target proteins from melanogenesis pathways. The highest tyrosinase inhibition capacity was observed in the ethanol extract, with values of 9.74 Kojic Acid Equivalent (KAE)/g extract (L-tyrosine) and 17.91 (KAE)/g extract (L-DOPA). Molecular docking analysis showed that the binding of eriodictyol 7-O-sophoroside (ΔG = -9.7 kcal/mol) has the best energy affinity for the PKC-β protein, genistein (ΔG = -7.5 kcal/mol) for the tyrosinase-related protein-1 (TYRP1) protein, eriodictyol 7-O-sophoroside (ΔG = -10.2 kcal/mol) for the cGMP protein, vincosamide (ΔG = -7.2 kcal/mol) for the microphthalmia-associated transcription factor (MITF) protein, and dicaffeoylquinic acid (ΔG = -7.4 kcal/mol) for the β-catenin protein. Based on a comparison of in-vitro and in-silico studies, melanogenesis inhibition is more potent in the PKC-β and cGMP pathways than direct tyrosinase inhibition because they exhibit lower binding energy.

Chemical composition and antioxidant, enzyme inhibition and cytoprotective activity of two Antarctic lichens of the genus Psoroma (Pannariaceae)

Lichens contain different types of chemical compounds with multiple biological activities that demonstrate their potential pharmacological use. This research aims to report the metabolomic identification of the ethanolic extracts of P. antarcticum and P. hypnorum, their antioxidant, enzyme inhibitory, and their cytoprotection activity. Sixteen metabolites were identified in P. antarcticum and twelve in P. hypnorum; the extracts reported variable antioxidant activity with IC50 >350 µg/mL in DPPH·, values >18 µmol Trolox/g in ORAC and >40 µmol Trolox/g in FRAP and a phenolic compound content >10 mg GAE/g, as well as significant results in cholinesterases, α-glucosidase, pancreatic lipase, α-amylase, and tyrosinase enzyme inhibition activities with IC50 ranging from 18 to 510 µg/mL, and which were complemented by molecular docking experiments. Both extracts showed improved cytoprotection at the concentrations of 0.5 to 1.0 μg/mL. This study contributes to the knowledge of the chemical diversity of Antarctic lichen extracts and their effectiveness in the evaluation of biological activities related to neurodegenerative diseases and metabolic syndrome.

Fatty Acid Composition, Antioxidant, and Enzyme Inhibition Activities of Cachrys Crassiloba (Boiss.) Meikle Fruit and Leaf Extracts

The genus Cachrys L. (Apiaceae) is distributed in the Mediterranean region and contains 11 species. C. crassiloba (Boiss.) Meikle is a species that grows in Southwest and Western Anatolia. Considering the literature studies, there were not enough studies on C. crassiloba. In this study, fatty acid composition, total phenol/flavonoid contents, antioxidant and acetyl-butrylcholinesterase, tyrosinase, and α-glucosidase enzyme inhibition activities of n-hexane and ethanol extracts prepared from C. crassiloba fruits and leaves were investigated by spectrophotometric methods at different concentrations. When the results were evaluated, it was found that the hexane extract of C. crassiloba leaf (123.92 ± 4.62 GA mg/g extract) had the highest total phenol content, while the ethanol extract of C. crassiloba fruit (134.38 ± 0.98 QE mg/g extract) had the highest flavonoid content. C. crassiloba hexane and ethanol leaf extracts (IC50= 8.04 ± 1.31 µg/mL; 10.30 ± 3.15 µg/mL) showed good antioxidant activity com-pared to the ascorbic acid (IC50= 14.59 ± 1.96 µg/mL) in DPPH assay. C. crassiloba leaf ethanol extract (IC50= 17.38 ± 5.02 µg/mL) has the highest ABTS scavenging activity. C. crassiloba extracts have mod-erate cholinesterase inhibitory activity. C. crassiloba leaf ethanol extract (IC50= 196.65 ± 1.94 µg/mL) has good tyrosinase enzyme inhibition activity. C. crassiloba leaf hexane extract (36.35% ± 1.13) was found to have significant inhibitory activity against α-glucosidase. In conclusion, besides its antioxidant activity, C. crassiloba may be effective against neurodegenerative diseases and skin disorders such as hyperpigmentation and diabetes mellitus, but further phytochemical analysis studies are required.

Tyrosinase Inhibitory Activity of n-Hexane, Ethyl Acetate and Methanol Extracts of Padina sp

Melanin is a color pigment in the skin, if produced in excess will cause browning of the skin. The formation of melanin (melanogenesis) is assisted by tyrosinase through two reactions, namely monophenolase and diphenolase. Melanogenesis can be reduced through the tyrosinase enzyme inhibition mechanism. Seaweed can be used as a tyrosinase inhibitor (brightening agent), such as Padina sp containing secondary metabolites such as alkaloids, flavonoids, terpenoids, phenolics, and saponins. This study aimed to determine the tyrosinase inhibitory activity of Padina sp. The extraction method used was graded maceration with n-hexane (n-Hx), ethyl acetate (Et-OAc), and methanol (Me-OH) solvents, then carried out phytochemical screening, antioxidant test using the DPPH method, and tyrosinase inhibitory test by measuring the enzymatic reaction using L-tyrosine (monophenolase) and L-DOPA (diphenolase). Phytochemical analysis of extracts by GC-MS and in silico analysis by molecular docking were also carried out. The results showed that the total yield of the three extracts was 5.50%. The three extracts had moderate category of antioxidants. The IC50 values monophenolase of n-Hx, Et-OAc, Me-OH extracts, and Kojic acid were 937.68; 132, 92; 268.68; and 20.99μg/mL, respectively. The IC50 values diphenolase of n-Hx, Et-OAc, Me-OH extracts, and Kojic acid were 989.74; 178.33; 356, 87; and 31.76 μg/mL, respectively. The phytochemical of Et-OAc extract based on GC-MS data showed a variety of compounds that have been shown to have pharmacological effects. This data is supported by the results of molecular docking analysis, where compound Spiro(tetrahydrofuryl)2.1'(decalin), 5',5',8'a-trimethyl (1) is able to show a relatively low binding energy, namely -6.86 kcal/mol. The binding energy is even lower than the standard compound (Kojic acid) interaction which only has binding energy of -3.73 kcal/mol. Based on the study carried out, extract from Padina sp has the potential to be developed as a a skin brightening agent.

Content analysis, nanoparticle forming potential and acaricidal effects on Tick (Hyalomma marginatum) of essential oils from two common Thymbra species

In this study, the fatty acid, essential oil and aroma composition of Thymbra sintenisii Bornm. & Aznav. subsp. sintenisii Bornm. & Aznav (TSS) and Thymbra sintenisii Bornm. & Azn. subsp. isaurica P.H.Davis (TSI) were determined by GC-MS. The cytotoxic activity was determined with MTT assay and antioxidant activities were determined with DPPH, ABTS, CUPRAC methods. Urease, acetyl, butyryl, angiotensin, α-amylase, tyrosinase, elastase, and collagenase enzyme inhibition activities of these species were also determined. The acaricidal effects of essential oils from aerial parts of TSS and TSI on ticks and the nanoparticle formation potential of their essential oils with AgNO3 were determined and compared. The main components of TSS essential oil and aroma were determined as carvacrol and o-cemen (66.78 and 35.44%, respectively), the major components of TSI essential oil and aroma were carvacrol and γ-terpinene (63.78 and 31.44%, respectively). The species exhibited remarkably high antioxidant activity, particularly in the ABTS and CUPRAC methods. It was also determined that the butyrylcholinesterase and acetylcholinesterase enzyme inhibition activities (Inhibition%: 76.12±0.83 and 74.13±0.33, respectively) of the species were quite high. Moderate antimicrobial activity against the bacteria was observed for both essential oils, with MIC values ranging from 312 to 1250 μg/mL. Moreover, essential oils of these species showed good acaricidal activity on Hyalomma marginatum (LC50: 11.82 μg/mL for TSS; LC50: 57.64 μg/mL for TSI). The high antioxidant, anticholinesterase, and acaracidal activities observed in both species are attributed to the presence of carvacrol in their essential oils. The species have potential to be used in food supplements-preservatives, pharmaceutical industry.

Phytochemical analyses by LC-HRMS, FTIR spectral analysis, antioxidant, antidiabetic and antityrosinase activity of Crataegus orientalis Pall. ex M. Bieb fruit extracted with various solvents.

Crataegus orientalis Pall. ex M. Bieb fruit (COPMB) is extensively used as a source of various products in the medicinal-aromatic field and holds the potential for erosion control, ornamental purposes, food source, and economic benefits for forest villagers from its fruits. This study aims to determine the chemical components and biological activities of extracts prepared from COPMB using different solvents. The present work was designed to define the antioxidant activity [phosphomolybdenum (total antioxidant capacity), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP), cupric ion-reducing antioxidant capacity (CUPRAC) and metal chelating activity (MCA)], phytochemical screening analysis, enzyme inhibitor (α-amylase, α-glucosidase and tyrosinase) potential, and liquid chromatography-high resolution mass spectrometry (LC-HRMS) secondary metabolite profiling in different extracts of COPMB. The results of LC-HRMS revealed that fumaric acid was the main phenolic compound in all extracts. Among the extracts, ethyl acetate extract has the highest phytochemical and antioxidant properties [total phenolic content (TPC): 32.5 mg GAE/g, total flavonoid content (TFC): 12.2 mg QE/g, ABTS: 213.0 mg TE/g; CUPRAC: 126.0 mg TE/g, MCA: 145.0 mg EDTA/g; FRAP: 122.8 mg TE/g; TAC: 2.8 mmol TE/g]. Ethyl acetate and methanol extracts are more effective in α-amylase (0.27 ± 0.01 mg/mL; 0.12 ± 0.00 mg/mL), α-glucosidase (0.63 ± 0.02 mg/mL; 0.77 ± 0.02 mg/mL) and tyrosinase (0.03 ± 0.00 mg/mL; 0.03 ± 0.00 mg/mL) enzyme inhibition potentials compared to standard acarbose (0.75 ± 0.02 mg/mL for α-amylase; 1.11 ± 0.03 mg/mL for α-glucosidase) and kojic acid (0.04 ± 0.00 mg/mL). The findings from this study suggest that COPMB could serve as a valuable source of natural agents for the food and pharmaceutical industry. © 2024 Society of Chemical Industry.

Anti-Aging Properties of Temulawak Extract (Curcuma xanthorrhiza L.) by In Vitro Assay

Highlights:1. Elastase, hyaluronidase, and tyrosinase can all be inhibited by temulawak extract.2. Temulawak extract has strong anti-aging ability and can be used as a candidate for cosmetic applications. AbstractThe process of aging is the gradual loss of a tissue's capacity to heal and maintain normal or physiological form and function. Elastase, hyaluronidase, and tyrosinase are the enzymes that contribute to skin aging. The anti-aging effect is connected to the inhibition of these enzymes' activity. Many medicinal plants with active metabolite have been utilized extensively to treat aging. Active compounds of temulawak (Curcuma xanthorrhiza L.) such as phenolic, curcuminoid and xanthorrhizol have potential as antiaging. This study aims to determine whether temulawak extract (TE), a potential candidate for cosmeceutical agent, has anti-aging characteristics by inhibiting the elastase, hyaluronidase, and tyrosinase enzymes. TE was processedxby PT FAST. Stock solution of TE was made by dissolving 20 mg of extract with 1 ml of DMSO 100%, the stock solution was then diluted to achieve the concentrations level 31.25 - 1000 μg/ml working solution of TE. The antiaging activity assays were carried out at PT Aretha Medika Utama. In vitro antiaging assay of TE includes elastase, hyaluronidase, and tyrosinase enzyme inhibition at 7 level of various concentrations of 2.08-66.67 μg/ml for anti-elastase assay, 5.21-166.67 μg/ml for anti-hyaluronidase assay, and 3.125-100 μg/ml for anti-tyrosinase assay with three replications. SPSS software was used to conduct the statistical analysis (p<0,05 is considered significant). TE exhibited highest inhibition percentage of 82.72%, 89.41%, and 94.17% for anti-tyrosinase, anti-elastase, and anti-hyaluronidase, respectively. The median inhibitory concentration (IC50) for elastase inhibitory activity was 10.66 μg/ml, hyaluronidase 70.39 μg/ml, and tyrosinase 55.87 μg/ml. According to this study, TE can be used as cosmeceu

Biological activity of enzymolysed ɩ-carrageenan of polydisperse nature

Sulfated polysaccharides from algae exhibit bioactivities and offer various health benefits. However, high molecular weight often restricts the bioavailability of these natural products. Polysaccharides with lower molecular weight, on the other hand, play a crucial role in enhancing various bioactive properties, including antioxidant activity, tyrosinase inhibition, cell proliferation, and more. The goal of this study was to produce a series of medium and lower molecular weight (Mw) ι-carrageenan samples and evaluate their bioactive potential. The ι-carrageenan samples with varying degradation levels and polydispersities were obtained after enzymatic treatment using a ι-carrageenase obtained from the marine bacterium Cellulophaga baltica. Compared to the non-degraded ι-carrageenan (I-0), the most degraded sample (I-5) showed 2.5 and 1.5 times higher antioxidant activities and inhibition of tyrosinase enzyme, respectively. Anticoagulant activity dropped by 1.8 times after 1200 min enzymolysis. The cell viability of I-5 treated RAW 264.7 cells was enhanced up to 140.6 ± 3.4% in comparison to the non-degraded one, while the highest proliferation rate was observed on I-5 treated both RAW267.4 and HaCaT cells. In addition, I-5-treated RAW264.7 cells showed the highest amount of Nitric oxide (NO) reduction, indicating a beneficial effect on inflammation. HaCaT cells treated with I-5 could migrate almost 90% of the wound area within 24 h compared to I-0, and the scratch area was completely closed at 48 h. A lower inflammation rate and higher HaCaT cell proliferation rate in I-5 displayed the ideal characteristics of wound healing material. These findings indicate that enzyme-degraded ι-carrageenans could be promising therapeutic agents in the cosmeceutical and pharmaceutical industries.

Antioxidant and antiaging activities of Cinnamomum burmannii, Michelia champaca and their combinations.

Aging is a natural skin process that occurs due to intrinsic and extrinsic factors, such as excessive exposure to ultraviolet light (photoaging). The mechanism of damage involves the production of excess free radicals that trigger oxidative stress in the skin. Determining the natural products that have high antioxidant activities as antiaging is important. Cinnamomum burmannii and Michelia champaca are typical Aceh plants that are believed to have high antioxidant effects. The aim of this study was to determining the contents of C. burmannii and M. champaca as well as to determine the antioxidant and antiaging activities of either individually or combinations. The qualitative phytochemical and semi-quantitative analysis of the extracts were measured using gas chromatography-mass spectroscopy (GC-MS). The antioxidant activity was examined by radical scavenging using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method while the antiaging activity was measured using the tyrosinase enzyme inhibition test. The phenolic and flavonoid contents of C. burmannii were higher than M. champaca (66.34 vs 24.71 mg gallic acid equivalent/gr and 80.52 vs 60.20 mg quercetin equivalent/gr, respectively. The inhibitory concentration (IC50) of M. champaca extract in inhibiting DPPH indicated that M. champaca had a better antioxidant activity than C. burmannii. The combination of C. burmannii and M. champaca extracts had a lower IC50 compared to M. champaca alone. C. burmannii and M. champaca extracts had a weak potential to inhibit tyrosinase activity (IC50 value ≥1000 μg/mL). In conclusion, this study indicates that M. champaca and C. burmannii have strong antioxidant activities and these might associate with polyphenol contents.

Hypoglycemic, anti-inflammatory, and anti-aging potential of Canthium coromandelicum (Burm.f.) Alston leaf extracts: In vitro and in silico ADMET studies

The present study focused on the hypoglycemic, anti-inflammatory and anti-aging effects of Canthium coromandelicum (Burm.f.) Alston leaf extract by in vitro and in silico analyses. In vitro antidiabetic activities were studied by α-amylase and α-glucosidase enzyme inhibition assays. The anti-inflammatory activity was analysed by bovine serum albumin denaturation assay and anti-aging activity by the inhibition of tyrosinase enzyme. The molecular docking study was undertaken to examine the binding mode and interactions of reported compounds of the hydroalcoholic extract of C. coromandelicum leaf with 7TAA, 3WY1, 2Y9X, and 4COX proteins. The plant exhibited promising antidiabetic effects with an inhibition of 86.09% against α-amylase and 83.53% against α-glucosidase enzymes. The extract had a notable anti-inflammatory activity with an inhibition range of 50.23 to 73.17%. The anti-aging activity showed 50.31 to 76.78% of inhibition in anti-tyrosinase assay with a potential effect in hyperpigmentation. In molecular docking analysis, the compounds like linoleic acid, phytol, methyl linoleate, palmitic acid and ethyl octa-decanoate had potent inhibitory activities against 7TAA, 3WY1, 2Y9X and 4COX proteins (6.90 to -4.42 kcal/mol) especially linoleic acid was found to be highly effective (-6.11 kcal/mol) antidiabetic effect with notable binding scores. The obtained results suggest that phytoconstituents identified from the plant have the potential in controlling diabetes by inhibiting α-amylase and α-glucosidase enzymes with promising anti-inflammatory and anti-aging properties. However, further research is required to ascertain its potential effect in experimental animals and isolation of bioactive compounds.

A Multi-Approach Study of Phytochemicals and Their Effects on Oxidative Stress and Enzymatic Activity of Essential Oil and Crude Extracts of Rosmarinus officinalis

Rosmarinus officinalis or Rosemary is a highly valued medicinal vegetal, owing to its notable antispasmodic, anti-inflammatory, and antibacterial properties. In the current work, we aimed to identify the chemical components of the essential oil (EO) of R. officinalis and evaluate its biological properties using an in vitro approach. High performance liquid chromatography time-of-flight mass spectrometry (HPLC-TOF-MS) was utilized to analyze of the hydro-methanolic extract (HME), while gas chromatography–mass spectrometry (GC/MS) was considered during the analysis of the EO’s chemical composition. The antioxidant abilities of HME and the EO were assessed using diverse tests (DPPH, ABTS, GOR, CUPRAC, and FRAP). The anti-enzymatic properties were tested by the inhibition of cholinesterases, α-glucosidase, and tyrosinase enzyme. The HPLC-TOF-MS displayed the existence of flavonoids like luteolin glucuronide I and II, and a few known hydroxycinnamic acids. The EO contained three major components, namely, eucalyptol (28.7%), camphor (16.7%), and borneol (13.5%). The HME had a high total polyphenol content, as determined by the Folin–Ciocalteau method (335.37 ± 9.33 µg of gallic acid eq·mg−1). Notably, the analysis of the bioactivities of the HME and EO revealed comparatively that they possessed higher radical scavenging capacity in the DPPH, ABTS, and galvinoxyl assays, while EO exhibited a higher capacity for enzyme inhibition. Overall, our findings suggest that both the EO and HME extract of Algerian’s R. officinalis holds great usefulness in the pharmaceutical and nutraceutical fields due to its elevated polyphenol content and potent bioactivities.

Data analysis of curcumin-chitosan loaded gold nanoparticles from Oryctes rhinoceros’s chitin mediated synthesis as a novel antimicrobial and whitening agent for cosmeceutical application.

It is a major aim in cosmeceutical industry to introduce effective and natural nanosized product. Thus, to obtain this goal, many nanotechnologies involving drug delivery for increasing the efficacy of active ingredients was studied. The efficacy is determined by their drug release profile, antimicrobial and anti-tyrosinase properties, and toxicity test. In this study, an in vitro drug release profile shows a cumulative drug release in 24 h of 52.99%. The tyrosinase enzyme inhibition is 66.385 ± 3.0%.The cytotoxicity of cell viability IC50 is 58% of the curcumin-chitosan gold nanoparticles (CCG-NP) concentration. To conclude, CCG-NP is a stable with a good drug release profile, enhanced both antimicrobial activity and anti-tyrosinase properties. Therefore, CCG-NP has great potential in cosmeceutical industry.

Phytochemical Composition, In Vitro Antimicrobial, Antioxidant, and Enzyme Inhibition Activities, and In Silico Molecular Docking and Dynamics Simulations of Centaurea lycaonica: A Computational and Experimental Approach.

Centaurea lycaonica is a local endemic species from the Centaurea L. genus. The Centaurea species has a wide range of usage in treating diseases in folk medicine. There are limited biological activity studies on this species in the literature. This study investigated enzyme inhibition and antimicrobial activity, antioxidant effect, and chemical content of extract and fractions of C. lycaonica. Enzyme inhibition activity was tested by α-amylase, α-glucosidase, and tyrosinase enzyme inhibition methods and antimicrobial activity by the microdilution method. The antioxidant activity was investigated using DPPH•, ABTS•+, and FRAP tests. The chemical content was determined by LC-MS/MS. The methanol extract showed the highest activity for α-glucosidase and α-amylase, even surpassing the positive control acarbose, with IC50 values of 56.333 ± 0.986 and 172.800 ± 0.816 μg/mL, respectively. Additionally, the ethyl acetate fraction also exhibited high activity for α-amylase with an IC50 value of 204.067 ± 1.739 μg/mL and tyrosinase with an IC50 value of 213.900 ± 1.553 μg/mL. Moreover, this extract and fraction were found to have the highest total phenolic and flavonoid contents and antioxidant activity. Additionally, LC-MS/MS analyses of active extract and fraction revealed mainly the presence of phenolic compounds and flavonoids. In silico molecular docking and molecular dynamics simulation studies of determining compounds apigenin and myristoleic acid, common in CLM and CLE extracts and active against α-glucosidase and α-amylase, were performed. In conclusion, methanol extract and ethyl acetate fraction showed potential enzyme inhibition and antioxidant activity as a natural agent. Molecular modeling studies corroborate the findings of in vitro activity analyses.

Anti-tyrosinase and antimelanogenic effect of cinnamic acid derivatives from Prunus mahaleb L.: Phenolic composition, isolation, identification and inhibitory activity.

The traditional use of Prunus species against skin diseases and especially for skin lightning cosmeceutical purposes is widespread in many cultures. Prunus mahaleb L. is a well known food plant and used in the baking industry for flavoring. The fruit kernels (endocarp) are used in India for hyperpigmentation. To investigate the chemical composition with the antimelanogenesis effect of P. mahaleb seed and kernel extracts and isolated compounds. Isolation studies performed from the methanol extracts obtained from kernels and structures were determined using NMR and MS analysis. Antimelanogenesis effect was determined by mushroom tyrosinase assay, cellular tyrosinase assay and melanin content assay using B16F10 murine melanoma cells. Five cinnamic acid derivatives were isolated and their structures (2-O-β-glucopyranosyloxy-4-methoxy-hydrocinnamic acid (1), cis-melilotoside (2), dihydromelilotoside (3), trans-melilotoside (4), 2-O-β-glucosyloxy-4-methoxy trans-cinnamic acid (5)) were elucidated using advanced spectroscopic methods. Mushroom tyrosinase enzyme inhibition of extracts, fractions and pure compounds obtained from P. mahaleb kernels were investigated and structure-activity relationship revealed. According to a detailed, comprehensive and validated LC-MS/MS technique analysis, vanilic acid (41.407mg/g), protocatechuic acid (8.992mg/g) and ferulic acid (4.962mg/g) in the kernel ethylacetate fraction; quinic acid (14.183mg/g), fumaric acid (8.349mg/g) and aconitic acid (5.574mg/g) were found as major phenolic compounds in the water fraction. The correlation of trace element copper content in extracts and fractions with mushroom enzyme activity was determined. By examining the enzyme kinetics of the compounds with effective cinnamic acid derivatives, inhibition types and enzyme binding constants Ki were calculated. Compounds 1,3 and 5 exhibited high noncompetitive tyrosinase inhibitory activity against L-tyrosine substrates, with IC50 values of 0.22, 0.31 and 0.37mM respectively. In addition compounds 1, 3 and 5 showed dose-dependent inhibitory effects on intracellular tyrosinase and melanin levels in α-melanocyte-stimulating hormone (α-MSH)-induced B16F10 melanoma cells. Potent tyrosinase inhibitory compounds and extracts of P. mahaleb kernels suggest that it could be a new, non-toxic and inexpensive resource for the cosmeceutical industry and in skin diseases associated with hyperpigmentation.

Potential of The Tyrosinase Enzyme Inhibition by Standardized Ethanol Extract And Ethyl Acetate Fraction of Bengkoang Peel (Pachyrhizus erosus L.)

This study examined the tyrosinase inhibitory potential of bengkoang peel standardised ethanolic extract and ethyl acetate fractions. 450 g of bengkoang peel powder (Pachyrhizus erosus L.) was macerated with 96% ethanol for 2 x 24 h, filtered, and concentrated till viscous. Extract standardisation uses specific and non-specific parameters. Microplate colorimetric tyrosinase inhibition assays were performed. The result of plant determination identified the bengkoang peel as Pachyrhizus erosus (L.) Urb. The organoleptic test revealed a brownish-yellow viscous extract, fresh smell, and bitter taste. Ethanol-soluble extract was 47.60% and water-soluble 22.42%. Bengkoang peel ethanolic extract includes alkaloids, flavonoids, saponins, tannins, and steroids. The non-specific parameters showed loss of drying (9.71%), water content (7.28%), total ash (9.91%), acid-insoluble ash (3.68%), no residual solvent content, lead content (-0.2324±0.1729), cadmium content (-0.0841±0.3418), TPC of 1 x 101 CFU/g, and TYMC of 2.26 x 102 CFU/g. The ethanol extract (103.9263) and ethyl acetate fraction (81.8606) IC50 values of bengkoang peel decrease tyrosinase enzyme activity compared to control (25.1235 ppm). These results show that the ethanol extract met both particular and non-specific quality standards. Bengkoang peel ethyl acetate inhibited tyrosinase.

Naturally-Occurring Tyrosinase Inhibitors Classified by Enzyme Kinetics and Copper Chelation.

Currently, there are three major assaying methods used to validate in vitro whitening activity from natural products: methods using mushroom tyrosinase, human tyrosinase, and dopachrome tautomerase (or tyrosinase-related protein-2, TRP-2). Whitening agent development consists of two ways, melanin synthesis inhibition in melanocytes and downregulation of melanocyte stimulation. For melanin levels, the melanocyte cell line has been used to examine melanin synthesis with the expression levels of TRP-1 and TRP-2. The proliferation of epidermal surfaced cells and melanocytes is stimulated by cellular signaling receptors, factors, or mediators including endothelin-1, α-melanocyte-stimulating hormone, nitric oxide, histamine, paired box 3, microphthalmia-associated transcription factor, pyrimidine dimer, ceramide, stem cell factors, melanocortin-1 receptor, and cAMP. In addition, the promoter region of melanin synthetic genes including tyrosinase is upregulated by melanocyte-specific transcription factors. Thus, the inhibition of growth and melanin synthesis in gene expression levels represents a whitening research method that serves as an alternative to tyrosinase inhibition. Many researchers have recently presented the bioactivity-guided fractionation, discovery, purification, and identification of whitening agents. Melanogenesis inhibition can be obtained using three different methods: tyrosinase inhibition, copper chelation, and melanin-related protein downregulation. There are currently four different types of inhibitors characterized based on their enzyme inhibition mechanisms: competitive, uncompetitive, competitive/uncompetitive mixed-type, and noncompetitive inhibitors. Reversible inhibitor types act as suicide substrates, where traditional inhibitors are classified as inactivators and reversible inhibitors based on the molecule-recognizing properties of the enzyme. In a minor role, transcription factors can also be downregulated by inhibitors. Currently, the active site copper iron-binding inhibitors such as kojic acid and chalcone exhibit tyrosinase inhibitory activity. Because the tyrosinase catalysis site structure is important for the mechanism determination of tyrosinase inhibitors, understanding the enzyme recognition and inhibitory mechanism of inhibitors is essential for the new development of tyrosinase inhibitors. The present review intends to classify current natural products identified by means of enzyme kinetics and copper chelation to exhibit tyrosinase enzyme inhibition.

Chemical composition, nutritional values, elemental analysis and biological properties of Prunus mahaleb L.: From waste to new potential sources for food, cosmetic and drug industry

Prunus mahaleb L. seeds are widely used in the baking industry as spice for flavouring. While achieving the mahaleb powder for commercial use in local companies, the seeds are sometimes mixed unintentionally with their kernels (stony shell) during sieving procedure. As the chemical and biological properties of the kernel of seeds are not well known, the kernel, seeds and the market sample obtained from a local supplier are decided to investigate individually. The antioxidant capacity and the trace element analyses of the seeds and kernels were performed by TEAC and CUPRAC assays and ICP-MS. The market sample was analysed for nutrient and oil composition. Fatty acid composition of the oil was determined with GC-FID and GC-MS methods. The chemical composition of the methanol extract of the seeds and kernels was studied by LC-MS/MS. Trace elements Mn, Co, Ni, Cu, Zn and Se were determined in the methanol extracts, ethyl acetate and water fractions. Mushroom tyrosinase enzyme inhibitions of 33 different extracts and fractions of various waste parts of the plant (kernel, fruit, twigs, flos, leaves) were investigated. The nutritional values showed that the market sample had high nutritious properties. The fatty acid content of the oil was found to be valuable in remedying dysfunctions of the body. Kernel ethylacetate fraction showed the highest tyrosinase enzyme inhibition. The role of copper element on enzyme activity was determined. The kernels are accepted as a waste material may also be evaluated as a good promising choice for food, cosmetic and drug industry.

Tyrosinase Inhibition, Antioxidant and Antibacterial Activity of Commercial Daisy Extract (Bellis perennis)

Extracts obtained from plant material have widely applied in the chemical and pharmaceutical industries because they contain significant concentrations of biologically active substances. Commercial daisy extract (Bellis perennis) was used in this paper for in vitro testing of tyrosinase enzyme inhibition, and antioxidant and antimicrobial activity. Inhibition of the tyrosinase enzyme was determined by monitoring dopachrome formation at a wavelength of 492 nm. Antioxidant activity was tested using FRAP and DPPH methods, while antibacterial activity was tested by diffusion technique on reference strains from the ATCC collection. The results showed that daisy extract inhibits tyrosinase enzyme in a dose-dependent manner. The extract effectively neutralized DPPH radicals and also showed good reducing ability. Bacterial strains used for in vitro antimicrobial activity testing did not show sensitivity to the extract concentrations used in this study.