Formaldehyde has been reported to be a potential human carcinogen due to its toxicity. However, formaldehyde releaser substances are still widely used as a preservative in cosmetics. Researchers have developed various methods for determining formaldehyde. One of the problems involved in the standard method is that of obtaining a derivatization agent, especially for routine analysis in the National Agency of Drug and Food, Indonesia. Therefore, this study aimed to develop a new method using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID). The significant modifications involved optimizations of five series of concentrations of p-toluenesulfonic (PTS) acid in ethanol (acidified ethanol), used as the derivatization agent, and the conditions of time and temperature of the reaction to yield the highest peak area. In addition, sample analysis was also carried out using the 2,4-dinitrophenylhydrazine (DNPH) method with high-performance liquid chromatography (HPLC) to compare the quantification results. The validated method showed intraday and interday precision, an accuracy (% RSD) of less than 3.7%, confidence interval 95.0–105.0%, a limit of detection and quantitation of 0.0099 and 0.0329 μg/mL (for DNPH by HPLC-DAD), 0.0158 and 0.0528 μg/mL (for PTS by SHS-GC-MS), and 1.1287 and 3.7625 μg/mL (for PTS liquid by GC-FID), respectively. These results have met the requirements for a validated analytical method and could be applied for routine analysis.
Conjugation of curcumin and gold with green chemistry is an approach to improve the effectiveness of curcumin as anti-fibrosis. In this work, curcumin and gold were conjugated to deliver curcumin to the liver. Curcumin-gold nanoparticles (cAuNPs) were prepared by varying curcumin pH and concentration. The successful of cAuNPs formation were identified by using UV-visible and FTIR spectrophotometers. The particle size and morphology were analyzed using particle size analyzer and cryo-TEM respectively. In vitro antioxidant assay was performed to determine the curcumin activity after conjugation. Physical and chemical stabilities of cAuNPs were studied for one month at 5 °C, 25 °C, and 40 °C. Furthermore, the cAuNPs activity to modulate early marker of fibrosis was tested on NIH/3T3 cells. The optimum condition for cAuNPs synthesis was by using 1.5 mM curcumin at pH 9.3. As compared to free curcumin, cAuNPs showed higher antioxidant activity and maintained the nanosize after stored for one month. In line with the antioxidant activity, cAuNPs 0.25–1 μg/mL reduced the collagen production by NIH/3T3 cells. More importantly, cAuNPs did not demonstrate any effect on the development of chicken embryo. Taken together, the attachment of gold to curcumin in the form of cAuNPs is promising for curcumin targeting to treat hepatic fibrosis.
Hepatitis C is still a serious liver case of health. Up to now the development of anti-Hepatitis C Virus (HCV) drugs is challenging, especially the development of natural material compounds as anti-HCV. In the present study, we evaluated the probability of α-mangostin, piperine, and β-sitosterol as anti-HCV with the in silico and in vitro approaches. Molecular docking was performed between nonstructural protein 5B (NS5B, PDB ID 3FQL) with α-mangostin, piperine, and β-sitosterol by Autodock Tools® and BIOVIA Discovery Studio®. Subsequently, molecular dynamics simulations were conducted for 200 ns, evaluating the dynamic interaction between the ligands and the viral protein NS5B. Furthermore, compound characterization at the hepatocarcinoma cell line was employed. α-Mangostin with NS5B complex demonstrated the most negative binding free energy value based on MM-PBSA calculation with a value of −9.13 kcal/mol. In vitro test showed that IC50 of α -mangostin was 2.70 ± 0.92 μM, IC50 of piperine was 52.18 ± 3.21 μM, IC50 of β-sitosterol was >100 μM. α-Mangostin can serve as a valuable lead compound for further development of the anti-HCV.
Insufficient surveillance and diagnosis result in a minimum of 150 million cases of serious fungal infections reported annually. The WHO has compiled a list of priority pathogens to encourage research and investment in fungal infections and antifungal resistance in late 2022. Among these, Candida albicans is classified as a critical pathogen. Fluconazole is widely recognized as an effective medication for the treatment and prevention of both mucosal and invasive candidiasis. Molecularly imprinted polymer (MIP) could enhance separation selectivity in fluconazole bioanalysis. The objective of this research is to develop an MIP for fluconazole by analyzing interactions identified in prior research and incorporating established improvements for MIP synthesis that cannot be observed through laboratory experimentation. Based on binding affinity, intermolecular hydrogen bonds, complexation energy, and thermodynamic characteristics, 2-acrylamido-1-ethanesulfonic acid was chosen as the optimal monomer. The HOMO–LUMO investigation revealed the localization of the orbitals from the guest to the host. The FMO study indicated that chloroform was the most suitable solvent for complex formation. The QTAIM, NBO, and NCI-RDG analyses identified the hydrogen bond formed between the H51 atom of the monomer and the N33 atom of fluconazole, determined to be the most significant hydrogen bond in the host–guest interaction. The interaction energy from multi-monomer interaction showed that a 1 : 6 ratio is the best ratio in forming a pre-polymerization complex between the template and monomer. Based on the findings of this study, it is anticipated that the computational analysis may be utilized for rational design for the enhancement of prior studies and future laboratory investigations.
Zebrafish serve as a pivotal model for bioimaging and toxicity assessments; however, the toxicity of banana peel-derived carbon dots in zebrafish has not been previously reported. The aim of this study was to assess the toxicity of carbon dots derived from banana peel in zebrafish, focusing on two types prepared through hydrothermal and pyrolysis methods. Banana peels were synthesized using hydrothermal and pyrolysis techniques and then compared for characteristics, bioimaging ability, and toxicity in zebrafish as an animal model. Pyrolysis-derived banana peel and hydrothermal-derived banana peel showed blue emission under ultraviolet light, indicating excitation-dependent behavior. To test their potential application for bioimaging, a soaking method was used using zebrafish that showed fluorescence intensity in the eyes, abdomen, and tail of zebrafish. Toxicity comparison showed that pyrolysis-derived banana peel had lower toxicity with 50% lethal concentrations (LC50) of 1707.3 ppm than hydrothermal-derived banana peel (LC50 993 ppm) in zebrafish. Both types of carbon dots showed significant differences (p<0.05) in hatching rates at 96 and 120 hours of exposure. Of the two methods for carbon dot synthesis from banana peel, the pyrolysis method had a higher toxicity threshold than the hydrothermal method, as indicated by the LC50 value and the number of zebrafish embryos that died, hatched delayed, and experienced malformation during their development.
The G1 phase of cell cycle progression is regulated by Cyclin-Dependent Kinase 4 (CDK4) as well as Cyclin-Dependent Kinase 6 (CDK6), and the acivities of these enzymes are regulated by the catalytic subunit, cyclin D. Cell cycle control through selective pharmacological inhibition of CDK4/6 has proven to be beneficial in the treatment of estrogen receptor-positive (ER-positive) breast cancer, particularly improving the progression-free survival of patients. Thus, targeting specific inhibition on CDK4/6 is bound to increase therapeutic efficiency. This study aimed to obtain CDK4/6 inhibitors through a pharmacophore-based virtual screening of the ZINC15 purchasable compound database using the in silico method. The pharmacophore model was designed based on the FDA-approved cdk4/6 inhibitor structures, and molecular docking was performed to further screen the hit compounds obtained. A total of eight compounds were selected based on docking results and interactions with CDK4 and CDK6, using palbociclib as the reference drug. According to the results, the compounds of ZINC585292724 and ZINC585291674 were the best compounds based on free binding energy, as well as hydrogen bond stability, and, therefore, exhibit potential as starting points in the development of CDK4/6 inhibitors.