196,669 research outputs found
Metal coordination and tyrosinase inhibition studies with Kojic-βAla-Kojic
No full textKojic acid is a natural antifungal and antibacterial agent that has been extensively studied for its tyrosinase inhibitory and metal coordination properties. Tyrosinase is a metalloenzyme with two copper ions in the active site. It is widely accepted that the tyrosinase inhibitory activity of kojic acid is related to its ability to coordinate metals. Over the past five years, we have used kojic acid to synthesize new and efficient bis-kojic acid chelators of iron and aluminium. In parallel, we investigated whether the de novo designed ligands could interfere with proper tyrosinase functioning. The present study combines our experience with inhibition and coordination studies of the new ligand: Kojic-βAla-Kojic. Research aimed at the assembly of a new potent tyrosinase inhibitor was based on the well-known crystal structure of the enzyme. Two questions were whether two kojic acids could act better than one and to what extent the length and kind of linker could ameliorate metal coordination, and inhibitory activity. Our results show that Kojic-βAla-Kojic has high affinity for Fe(III), Al(III), Zn(II), and Cu(II) and strong tyrosinase inhibitory effect and it can be proposed for use in industrial and pharmaceutical applications
SCCS Opinion on Kojic Acid - SCCS/1637/21 - Final version
No full textInternational audienceSCCS Opinion on Kojic Acid - SCCS/1637/21 - Final versionU. Bernauer, L. Bodin, Q. Chaudhry, P.J. Coenraad, M. Dusinska, J. Ezendam, E. Gaffet, C. L. Galli, B. Granum, E. Panteri, V. Rogiers, Ch. Rousselle, M. Stepnik, T. Vanhaecke, S. Wijnhoven, A. Koutsodimou, W. Uter, N. von GoetzThe SCCS adopted this document at its plenary meeting on 15 and 16 March 2022 (85 Pages)Mise en ligne 17 Mars 2022https://ec.europa.eu/health/publications/kojic-acid_enDescriptionSCCS members: U. Bernauer, L. Bodin, Q. Chaudhry, P.J. Coenraads (Chairperson), M. Dusinska, J. Ezendam, E. Gaffet, C.L. Galli, B. Granum, E. Panteri, V. Rogiers (Rapporteur), Ch. Rousselle, M. Stepnik, T. Vanhaecke (Rapporteur), S. WijnhovenSCCS external experts: A. Koutsodimou, W. Uter, N. von GoetzContact:[email protected] request from: European CommissionSCCS Number: SCCS/1637/21Adopted on: 15-16 March 2022Conclusion of the opinion:(1) In light of the data provided and taking under consideration the concerns related to potential endocrine disrupting properties of Kojic acid, does the SCCS consider Kojic acid safe when used in cosmetic products up to a maximum concentration of 1 %?On the basis of the safety assessment, and considering the concerns related to potential endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that Kojic acid is not safe when used as a skin lightening agent in cosmetic products at concentrations of up to 1%.(2) Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Kojic acid in cosmetic products?In the SCCS’s opinion, the use of Kojic acid as a skin lightening agent in cosmetic products is safe for the consumer up to a maximum concentration of 0.7% Kojic acid in the final product.(3) Does the SCCS have any further scientific concerns with regard to the use of Kojic acid in cosmetic products?As Kojic acid is sometimes added to peeling agents, a weakened skin barrier may be of additional concern because of greater dermal absorption.Only the topical use of Kojic acid in cosmetics has been considered in this Opinion. Other uses (e.g. food) of natural or synthetic sources have not been considered.As far as the derivatives of Kojic acid are concerned, e.g. esters of Kojic acid such as Kojic acid dipalmitate and Kojic acid isopalmitate, and derivatives such as chloro-Kojic acid, these have not been included in this Opinion as no data has been submitted.Keywords:SCCS, revision, scientific opinion, Kojic acid, CAS No 501-30-4, EC No 207-922-4, Regulation 1223/2009Opinion to be cited as:SCCS (Scientific Committee on Consumer Safety), scientific opinion on Kojic acid, preliminary version of 26-27 October 2021, final version of 15-16 March 2022, SCCS/1637/21
SCCS Opinion on Kojic Acid - SCCS/1637/21 - Preliminary version
No full textInternational audienceKojic acidSCCS members: U. Bernauer, L. Bodin, Q. Chaudhry, P.J. Coenraads (Chairperson), M. Dusinska, J. Ezendam, E. Gaffet, C.L. Galli, B. Granum, E. Panteri, V. Rogiers, Ch. Rousselle, M. Stepnik, T. Vanhaecke (Rapporteur), S. WijnhovenSCCS external experts: A. Koutsodimou, W. Uter, N. von GoetzContact: [email protected] request from: European CommissionSCCS Number: SCCS/1637/21Adopted on: 26-27 October 2021Conclusion of the opinion:(1) In light of the data provided and taking under consideration the concerns related to potential endocrine disrupting properties of Kojic acid, does the SCCS consider Kojic acid safe when used in cosmetic products up to a maximum concentration of 1 %?On the basis of the safety assessment, and considering the concerns related to potential endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that the concentration of 1% Kojic acid is not safe for the intended use in cosmetic products.(2) Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Kojic acid in cosmetic products?Without specific data on the different cosmetic products containing Kojic acid, the SCCS is unable to advice on the safe concentration of Kojic acid in individual cosmetic products. As an example, for the combined twice a day use of face cream and hand cream, the maximum concentration of Kojic acid should not exceed 0.04%.(3) Does the SCCS have any further scientific concerns with regard to the use of Kojic acid in cosmetic products?As Kojic acid is sometimes added to peeling agents, a weakened skin barrier may be of additional concern because of greater dermal absorption.Only the topical use of Kojic acid in cosmetics has been considered in this Opinion. Other uses (e.g. food) of natural or synthetic sources have not been considered.As far as the derivatives of Kojic acid are concerned, e.g. esters of Kojic acid such as Kojic acid dipalmitate and Kojic acid isopalmitate, and derivatives such as chloro-Kojic acid, these have not been included in this Opinion as no data has been submitted.Keywords:SCCS, revision, scientific opinion, Kojic acid, CAS No 501-30-4, EC No 207-922-4, Regulation 1223/2009Opinion to be cited as:SCCS (Scientific Committee on Consumer Safety), scientific opinion on Kojic acid, preliminary version of 26-27 October 2021, SCCS/1637/21
SCCS Opinion on Kojic Acid - SCCS/1637/21 - Preliminary version
No full textInternational audienceKojic acidSCCS members: U. Bernauer, L. Bodin, Q. Chaudhry, P.J. Coenraads (Chairperson), M. Dusinska, J. Ezendam, E. Gaffet, C.L. Galli, B. Granum, E. Panteri, V. Rogiers, Ch. Rousselle, M. Stepnik, T. Vanhaecke (Rapporteur), S. WijnhovenSCCS external experts: A. Koutsodimou, W. Uter, N. von GoetzContact: [email protected] request from: European CommissionSCCS Number: SCCS/1637/21Adopted on: 26-27 October 2021Conclusion of the opinion:(1) In light of the data provided and taking under consideration the concerns related to potential endocrine disrupting properties of Kojic acid, does the SCCS consider Kojic acid safe when used in cosmetic products up to a maximum concentration of 1 %?On the basis of the safety assessment, and considering the concerns related to potential endocrine disrupting properties of Kojic acid, the SCCS is of the opinion that the concentration of 1% Kojic acid is not safe for the intended use in cosmetic products.(2) Alternatively, what is according to the SCCS the maximum concentration considered safe for use of Kojic acid in cosmetic products?Without specific data on the different cosmetic products containing Kojic acid, the SCCS is unable to advice on the safe concentration of Kojic acid in individual cosmetic products. As an example, for the combined twice a day use of face cream and hand cream, the maximum concentration of Kojic acid should not exceed 0.04%.(3) Does the SCCS have any further scientific concerns with regard to the use of Kojic acid in cosmetic products?As Kojic acid is sometimes added to peeling agents, a weakened skin barrier may be of additional concern because of greater dermal absorption.Only the topical use of Kojic acid in cosmetics has been considered in this Opinion. Other uses (e.g. food) of natural or synthetic sources have not been considered.As far as the derivatives of Kojic acid are concerned, e.g. esters of Kojic acid such as Kojic acid dipalmitate and Kojic acid isopalmitate, and derivatives such as chloro-Kojic acid, these have not been included in this Opinion as no data has been submitted.Keywords:SCCS, revision, scientific opinion, Kojic acid, CAS No 501-30-4, EC No 207-922-4, Regulation 1223/2009Opinion to be cited as:SCCS (Scientific Committee on Consumer Safety), scientific opinion on Kojic acid, preliminary version of 26-27 October 2021, SCCS/1637/21
Application of TiO2/Fe3O4/MWCNTs nanocomposite conductive mediator for fabrication of Kojic acid sensor
No full textThis research work focused on kojic acid determination using carbon-paste electrode (CPE) improved with TiO2/Fe3O4/MWCNTs nanocomposite and ionic liquid (TiO2/Fe3O4/MWCNTs/IL-CPE). Redox behavior of kojic acid as an antioxidant food additive was examined by different electrochemical techniques. The recording results confirmed TiO2/Fe3O4/MWCNTs/IL-CPE could improve redox behavior of kojic acid in current and potential cases. The TiO2/Fe3O4/MWCNTs/IL-CPE showed linear relation with kojic acid concentration in the range 0.5 μM-300.0 μM with detection limit 0.2 μM using the DPV. The TiO2/Fe3O4/MWCNTs/IL-CPE was used to determine kojic acid in real food samples. © 2020 The Authors
Novel kojic acid-polymer-based magnetic nanocomposites for medical applications
No full textSamer Hasan Hussein-Al-Ali,1 Mohamed Ezzat El Zowalaty,2,5 Mohd Zobir Hussein,3 Maznah Ismail,1,4 Dena Dorniani,3 Thomas J Webster6,7 1Laboratory of Molecular Biomedicine, 2Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, 3Materials Synthesis and Characterization Laboratory, Institute of Advanced Technology, 4Department of Nutrition and Dietetics, Faculty of Medicine and Health Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 5Faculty of Public Health and Tropical Medicine, Jazan University, Jazan, Saudi Arabia; 6Department of Chemical Engineering and Program in Bioengineering, Northeastern University, Boston, MA, USA; 7Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia Abstract: Iron oxide magnetic nanoparticles (MNPs) were synthesized by the coprecipitation of iron salts in sodium hydroxide followed by coating separately with chitosan (CS) and polyethylene glycol (PEG) to form CS-MNPs and PEG-MNPs nanoparticles, respectively. They were then loaded with kojic acid (KA), a pharmacologically bioactive natural compound, to form KA-CS-MNPs and KA-PEG-MNPs nanocomposites, respectively. The MNPs and their nanocomposites were characterized using powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, vibrating sample magnetometry, and scanning electron microscopy. The powder X-ray diffraction data suggest that all formulations consisted of highly crystalline, pure magnetite Fe3O4. The Fourier transform infrared spectroscopy and thermogravimetric analysis confirmed the presence of both polymers and KA in the nanocomposites. Magnetization curves showed that both nanocomposites (KA-CS-MNPs and KA-PEG-MNPs) were superparamagnetic with saturation magnetizations of 8.1 emu/g and 26.4 emu/g, respectively. The KA drug loading was estimated using ultraviolet–visible spectroscopy, which gave a loading of 12.2% and 8.3% for the KA-CS-MNPs and KA-PEG-MNPs nanocomposites, respectively. The release profile of the KA from the nanocomposites followed a pseudo second-order kinetic model. The agar diffusion test was performed to evaluate the antimicrobial activity for both KA-CS-MNPs and KA-PEG-MNPs nanocomposites against a number of microorganisms using two Gram-positive (methicillin-resistant Staphylococcus aureus and Bacillus subtilis) and one Gram-negative (Salmonella enterica) species, and showed some antibacterial activity, which could be enhanced in future studies by optimizing drug loading. This study provided evidence for the promise for the further investigation of the possible beneficial biological activities of KA and both KA-CS-MNPs and KA-PEG-MNPs nanocomposites in nanopharmaceutical applications. Keywords: chitosan, polyethylene glycol, magnetic nanoparticle, kojic acid, controlled release, biological activit
The comparative fate of T-2 toxin in chickens and ducks, and an investigation of kojic acid's toxicity and its possible synergy with aflatoxin in chickens
No full textTypescript (photocopy)VitaMajor subject: ToxicologyThe metabolism and/or toxicological effects of 3 mycotoxins were studied in poultry. In the metabolism study, a tritiated preparation of the trichothecene mycotoxin T-2 toxin was administered as a single oral dose to 21-day old male broiler (Hubbard x Hubbard) chickens and to the more sensitive male White Pekin ducks. At 6, 12, 24, and 48 hours post-administration, 3 birds of each species were killed and various tissues were collected, as was excreta at various times after treatment. To determine the amount of radioactivity in the excreta and tissues, samples were subjected to oxygen combustion analysis. There were no major differences between the 2 species in absorption, kinetics, metabolism, tissue retention or excretion of T-2 toxin and its metabolites. The 10-fold difference in toxicological sensitivity to T-2 toxin that exists between these 2 species could not be attributed to differences in the time course of metabolic detoxification or to differences in rates of excretion. To examine the toxicological effects of kojic acid and its possible synergy with aflatoxin, studies of male broiler (Peterson x Hubbard) chickens were conducted over a 21-day period beginning at day of hatch. In the toxicity study, 6 treatments of kojic acid at 0,.5, 1, 2, 4, and 8 g kojic acid/kg feed were used to establish a toxic response. In the synergy study, treatments of 0 or 2.5 g kojic acid/kg feed, and 2.5 mg aflatoxin/kg feed were used in a 2 x 2 design. The toxicity of kojic acid was evident only at concentrations greater than 2 g kojic acid/kg feed and was characterized by significant (P <.05) decreases in body weights and colonic temperature, increases in relative organ weights; and various changes in both serum enzyme activities and serum metabolites. Although significant (P <.05) effects of aflatoxin and kojic acid alone were observed in the synergy study, these data did not reveal any toxic synergy existing between the 2 mycotoxins. However, kojic acid did significantly (P <.05) antagonize aflatoxin's deleterious effects upon the mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration
Tyrosinase inhibition activity profile of five standardized extracts of <i>M</i>. <i>nigra</i> leaves and kojic acid.
No full textTyrosinase inhibition activity profile of five standardized extracts of M. nigra leaves and kojic acid.</p
Kojic acid: Production of kojic acid from crude glycerol.
No full textKojic acid production using selected filamentous fungus isolated from the Brazilian biodiversity. The production is carried out in a submerged fermentation with crude glycerol (glycerin), a biodiesel co-product, or a commercial standard glycerol as the sole source of carbon.TC 193
The effect of L-DOPA and kojic acid on morphology of <i>M. furfur</i> NBRC 0656 when culturing in MM (A), MM with 1 mM L-DOPA (B), MM with 1 mM L-DOPA and kojic acid at 600 (C), 800 (D), 1,000 (E) 1,200 (F) 1,500 (G) µg/ml, and MM with 1,000 µg/ml kojic acid (H). Bars represent 5 µm.
No full text<p>The effect of L-DOPA and kojic acid on morphology of <i>M. furfur</i> NBRC 0656 when culturing in MM (A), MM with 1 mM L-DOPA (B), MM with 1 mM L-DOPA and kojic acid at 600 (C), 800 (D), 1,000 (E) 1,200 (F) 1,500 (G) µg/ml, and MM with 1,000 µg/ml kojic acid (H). Bars represent 5 µm.</p
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