scholarly journals Zinc(II) Complexes of Amino Acids as New Active Ingredients for Anti-Acne Dermatological Preparations

2021 ◽  
Vol 22 (4) ◽  
pp. 1641
Author(s):  
Michał Abendrot ◽  
Elżbieta Płuciennik ◽  
Aleksandra Felczak ◽  
Katarzyna Zawadzka ◽  
Ewelina Piątczak ◽  
...  

Zinc compounds have a number of beneficial properties for the skin, including antimicrobial, sebostatic and demulcent activities. The aim of the study was to develop new anti-acne preparations containing zinc–amino acid complexes as active ingredients. Firstly, the cytotoxicity of the zinc complexes was evaluated against human skin fibroblasts (1BR.3.N cell line) and human epidermal keratinocyte cell lines, and their antimicrobial activity was determined against Cutibacterium acnes. Then, zinc complexes of glycine and histidine were selected to create original gel formulations. The stability (by measuring pH, density and viscosity), microbiological purity (referring to PN-EN ISO standards) and efficacy of the preservative system (according to Ph. Eur. 10 methodology) for the preparations were evaluated. Skin tolerance was determined in a group of 25 healthy volunteers by the patch test. The preparations containing zinc(II) complexes with glycine and histidine as active substances can be topically used in the treatment of acne skin due to their high antibacterial activity against C. acnes and low cytotoxicity for the skin cells. Dermatological recipes have been appropriately composed; no irritation or allergy was observed, and the preparations showed high microbiological purity and physicochemical stability.

2020 ◽  
Vol 90 (5-6) ◽  
pp. 439-447 ◽  
Author(s):  
Andrew Hadinata Lie ◽  
Maria V Chandra-Hioe ◽  
Jayashree Arcot

Abstract. The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%–26% and 48%–76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Kyung-Ha Lee ◽  
Jeong Pyo Lee ◽  
Wanil Kim

AbstractActive ingredients derived from natural sources are widely utilized in many industries. Cosmetic active ingredients are largely derived from various plants. In this study, we examined whether a mixture of plant extracts obtained from agrimonia, houttuynia, licorice, peony, and phellodendron (hereafter AHLPP), which are well-known for their effects on skin, could affect skin barrier function, inflammation, and aging in human skin cells. We also determined whether AHLPP extracts sterilized using γ-irradiation (to avoid preservatives) retained their skin cell regulating activity. The AHLPP mixture could downregulate representative pro-inflammatory cytokines including IL 1-β and IL 7. Procollagen peptide synthesis was also increased by AHLPP treatment along with mRNA upregulation of barrier proteins such as filaggrin and desmoplakin. The AHLPP mixture showed an anti-aging effect by significantly upregulating telomerase activity in human keratinocytes. We further observed TERT upregulation and CDKN1B downregulation, implying a weakening of pro-aging signal transduction. Co-cultivation of a hydrogel polymer containing the AHLPP mixture with human skin cells showed an alteration in skin-significant genes such as FLG, which encodes filaggrin. Thus, the AHLPP mixture with or without γ-irradiation can be utilized for skin protection as it alters the expression of some significant genes in human skin cells.


2012 ◽  
Vol 48 (4) ◽  
pp. 691-698
Author(s):  
Carolina Alves dos Santos ◽  
Laura Oliveira-Nascimento ◽  
Marcos Camargo Knirsch ◽  
Marco Antônio Stephano ◽  
Adalberto Pessoa Júnior ◽  
...  

Ceftazidime is a broad spectrum antibiotic administered mainly by the parenteral route, and it is especially effective against Pseudomonas aeruginosa. The period of time in which serum levels exceed the Minimum Inhibitory Concentration (MIC) is an important pharmacodynamic parameter for its efficacy. One of the forms to extend this period is to administer the antibiotic by continuous infusion, after prior dilution in a Parenteral Solution (PS). The present work assessed the stability of ceftazidime in 5% glucose PS for 24 hours, combined or not with aminophylline, through High Performance Liquid Chromatography (HPLC). The physicochemical evaluation was accompanied by in vitro antimicrobial activity compared MIC test in the 24-hour period. Escherichia coli and Pseudomonas aeruginosa were the microorganisms chosen for the MIC comparison. The HPLC analysis confirmed ceftazidime and aminophylline individual stability on PS, while the MIC values were slightly higher than the mean described in the literature. When both drugs were associated in the same PS, the ceftazidime concentration by HPLC decreased 25% after 24 hours. Not only did the MIC values show high loss of antibiotic activity within the same period, but also altered MIC values immediately after the preparation, which was not detected by HPLC. Our results indicate that this drug combination is not compatible, even if used right away, and that PS might not be the best vehicle for ceftazidime, emphasizing the importance of the MIC evaluation for drug interactions.


Author(s):  
Jean-Daniel Hecq ◽  
Benoit Bihin ◽  
Jacques Jamart ◽  
Laurence Galanti

AbstractIn hospitals, a major part of the drugs is administered via the intravenous route. When one wants to evaluate or know the stability of a drug in solution, it is necessary to know several physico-chemical parameters. Several reference works are available to help the hospital pharmacist with this research. However, reading these different sources can make you discover conflicting data. It is therefore necessary at this time to obtain the publications with contradictory results and to read them again. Seven criteria have been identified for judging the quality of a publication on physicochemical stability: full description of equipment, methods and analytical conditions of molecules studied; complete description of the procedures used to validate the analytical method; full indication of time testing and measurement bases or control; documentation on the analytical reproducibility; adequate statistical analysis; appropriate conclusions; appropriate references. In conclusion, everything in a compatibility study is important.


Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2261
Author(s):  
Oscar López-Balladares ◽  
Patricio J. Espinoza-Montero ◽  
Ramiro Acosta-Sandoval

The physicochemical properties of pastry and confectionery products greatly influence the aesthetic design of a cake topping, since they can be susceptible to physicochemical changes in a very short time, so maintaining a good appearance and texture of the topping becomes a challenge. Generally, cake creams deteriorate over time. The evaluation of the physicochemical properties of natural gums (arabic gum, tara gum, carrageenan, and pectin) is proposed in this work as a way to improve the physicochemical stability of butter-based cake creams (coverage creams) to maintain the initial appearance of the cream and to lengthen the separation time of their phases. For this purpose, some parameters related to the physicochemical stability of the cream, such as viscosity, density, bubble size, syneresis, volume and rheological behavior were measured. The result of the ANOVA and Tukey’s tests displayed significant differences for the measured parameters, which shows that natural gums substantially improve the stability of butter cream. The best natural gum found was the tara gum (TG) which improved viscosity 5.6 times with respect to that of the cream without gums (η¯ without gums = 15.49 Pa·s, η¯ with TG = 87.09 Pa·s), while the bubble size remained small, 1.6 times smaller compared to that of the cream without gum (BS¯) without gums = 57 μm, (BS¯) with TG = 35 μm), and the volume loss decreased two times when compared to that of the cream without gums ((ΔV¯) without gums = 1.57 cm3, (ΔV¯) with TG = 0.80 cm3). The cream with TG showed better rheology compared to that of the cream without gums (the cream without gums exhibited a plastic and thixotropic behavior, with permanent elastic deformation, while cream with TG exhibited thixotropic behavior without permanent elastic deformation). Finally, it was found that the cream with TG acquired a higher thixotropic index (TI) compared to that of the cream without gums (TI max. without gums = 17.40 y 71.78 q.u., TI max. with TG = 74.67 and 1559.90 q.u., at 4 °C and 25 °C, respectively) which demonstrates the effective contribution of cream with TG in 66.67% of the measured parameters.


2018 ◽  
Vol 0 (0) ◽  
Author(s):  
Anne-Claire Bonnaure ◽  
Romain Bellay ◽  
Pauline Rault ◽  
Marie-Antoinette Lester ◽  
Pierre-Nicolas Boivin

Abstract Background Prednisone is a corticosteroid used in several inflammatory diseases and cancers. In France, no available prednisone drinkable formulation exists. Instead, an oral syrup of prednisone with ethanol, sodium benzoate and simple syrup is produced. However, sodium benzoate can induce neonatal icterus and alcohol is not authorized for children below 3 years of age. The aim of this study was to determine the stability of 5 mg/mL prednisone oral suspension in a commercial compounding excipient: Syrspend® SF PH4. Methods Three batches of oral suspensions were prepared, using micronized prednisone and Syrspend® SF PH4. They were packaged in amber glass vials and stored at room temperature. On day 0, 1, 4, 10, 30, 60 and 90, we observed physical and chemical stability (pH measurement, osmolality measurement, residual concentrations of prednisone and degradation product identification). A stability indicating method was developed using high performance liquid chromatography with Ultraviolet detection at 254 nm. Results Prednisone concentrations remained stable within ± 5 % of nominal values for 60 days. No degradation product and change of physicochemical properties were detected. Conclusion This study showed that 5 mg/mL prednisone oral suspension in Syrspend® SF PH4 is stable for 60 days, at room temperature and protected from light.


2009 ◽  
Vol 4 (12) ◽  
pp. 1934578X0900401 ◽  
Author(s):  
Wang Meng ◽  
Ren Xiaoliang ◽  
Gao Xiumei ◽  
Franco Francesco Vincieri ◽  
Anna Rita Bilia

Studies on stability of active ingredients are fundamental and critical for the rational development of Traditional Chinese Medicine (TCM) in view of its modernization and worldwide use. The stability of both active and marker constituents of plants used in TCM is reviewed for the first time. More than 100 papers, mostly written in Chinese, have been reviewed. Studies concerning plant constituents were analyzed according to their chemical classification of active ingredients. In addition, several crude drugs of animal origin are also reported. Stability of active ingredients is summarized during extraction and/or storage of the herbal drug preparations, and under stress conditions (pH, temperature, solvents, light, and humidity) and in the presence of preservatives, antioxidants, and metals.


Author(s):  
Karl-Jan Spittaels ◽  
Ruben Ongena ◽  
Christos C. Zouboulis ◽  
Aurélie Crabbé ◽  
Tom Coenye

2018 ◽  
Vol 47 (13) ◽  
pp. 4607-4612 ◽  
Author(s):  
Minh Tho Nguyen ◽  
Bulat Gabidullin ◽  
Georgii I. Nikonov

The new zinc complexes 2,6-(ArNCH)2C6H3ZnBu (6) and 2,6-(ArNCH)2C6H3ZnCl2Li(THF)3 (7), supported by a bis(imino)phenyl NCN pincer ligand, were prepared (Ar = 2,6-iPr2C6H3).


2020 ◽  
Author(s):  
Svenja Roosch ◽  
Vincent Felde ◽  
Daniel Uteau ◽  
Stephan Peth

&lt;p&gt;Soil microaggregates are considered to play an important role in soil functioning and soil organic carbon (SOC) is of great importance for the formation and stabilization of these aggregates. The loss of SOC can occur, for example, after a change in land use and may lead to a decreased aggregate stability, which makes soils vulnerable to various threats, such as erosion or compaction. It is therefore important to understand the effect of SOC loss on aggregate stability in order to better understand and preserve the functioning of healthy soils.&lt;/p&gt;&lt;p&gt;We sampled two adjacent plots from a loess soil in Selhausen (North Rhine-Westphalia, Germany) in November of 2019 and measured aggregate stability and architecture of soil microaggregates. One plot was kept free from vegetation by the application of herbicides and by tillage (to a depth of 5&amp;#160;cm) from 2005 on, while the other plot was used for agriculture (conventional tillage). Over the course of 11 years, the SOC concentration in the bulk soil was reduced from 12.2 to 10.1&amp;#160;g SOC kg&lt;sup&gt;-1&lt;/sup&gt; soil. We took 10 undisturbed soil cores from two depths of each plot (Ap and Bt horizons).&lt;/p&gt;&lt;p&gt;The stability of aggregates against hydraulic and mechanical stresses was tested using the widespread wet sieving approach and a newly developed dry crushing approach. Isolated microaggregates gained from the latter procedure were tested against tensile stress by adapting a crushing test in a load frame to the microaggregate scale. To shed light on the effect of a decreased SOC content on microaggregate structure, we scanned several microaggregates with a high-resolution computed tomography scanner (Zeiss Xradia 520 versa) at sub-micron resolutions and analyzed the features of their pore systems.&lt;/p&gt;&lt;p&gt;This will give us valuable insights into the interplay of mechanical and physicochemical stability, as well as the structural properties of microaggregates with regard to SOC depletion. The consequences for various soil functions provided by microaggregates, like the habitat function for microorganisms or their capacity to store and transport gas, water and nutrients, are discussed.&lt;/p&gt;


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