Molecules

16 pages, 3546 KiB

Open AccessArticle

Laser Spectroscopic Characterization for the Rapid Detection of Nutrients along with CN Molecular Emission Band in Plant-Biochar

by Tahani A. Alrebdi, Amir Fayyaz, Haroon Asghar, Samira Elaissi and Lamia Abu El Maati

Molecules 2022, 27(15), 5048; https://doi.org/10.3390/molecules27155048 - 08 Aug 2022

Cited by 10 | Viewed by 2072

Abstract

We report a quantitative analysis of various plant-biochar samples (S1, S2 and S3) by utilizing a laser-induced breakdown spectroscopy (LIBS) technique. For LIBS analysis, laser-induced microplasma was generated on the target surface by using a focused beam through a high-power Nd: YAG laser [...] Read more.

We report a quantitative analysis of various plant-biochar samples (S1, S2 and S3) by utilizing a laser-induced breakdown spectroscopy (LIBS) technique. For LIBS analysis, laser-induced microplasma was generated on the target surface by using a focused beam through a high-power Nd: YAG laser and optical emission spectra were recorded using a charged coupled device (CCD) array spectrometer, with wavelength ranges from 200 nm to 720 nm. The spectroscopical analysis showed the existence of various ingredients, including H, Li, Ca, Na, Al, Zn, Mg, Sr, Si, and Fe, along with a CN molecular emission band due to B²Σ⁺ − X²Σ⁺ electronic transition. By assuming conditions of the plasma is optically thin and in LTE, calibration-free laser-induced breakdown spectroscopy (CF-LIBS) was utilized for the compositional analysis of the ingredients present in the three plant-biochar samples. To lower the uncertainties, we used an average composition (%) of the three plant-biochar samples. The quantitative study of the plant-biochar samples was also achieved using the energy dispersive X-ray (EDX) technique, showing good agreement with the CF-LIBS technique. In addition, statistical analysis, such as principal component analysis (PCA), was performed for the clustering and classification of the three plant-biochar samples. The first three PCs explained an overall ~91% of the variation in LIBS spectral data, including PC1 (58.71%), PC2 (20.9%), and PC3 (11.4%). These findings suggest that LIBS is a robust tool for rapid measurement of heavy as well as light elements, such as H, Li, and nutritional metals in plant-biochar samples. Full article

(This article belongs to the Special Issue Laser Spectroscopic Characterization of the Organic Chromophores)

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24 pages, 7786 KiB

Open AccessArticle

Modified Benzoxazole-Based VEGFR-2 Inhibitors and Apoptosis Inducers: Design, Synthesis, and Anti-Proliferative Evaluation

by Alaa Elwan, Abdallah E. Abdallah, Hazem A. Mahdy, Mohammed A. Dahab, Mohammed S. Taghour, Eslam B. Elkaeed, Ahmed B. M. Mehany, Ahmed Nabeeh, Mohammed Adel, Aisha A. Alsfouk, Hazem Elkady and Ibrahim H. Eissa

Molecules 2022, 27(15), 5047; https://doi.org/10.3390/molecules27155047 - 08 Aug 2022

Cited by 27 | Viewed by 2445

Abstract

This work is one of our efforts to discover potent anticancer agents. We modified the most promising derivative of our previous work concerned with the development of VEGFR-2 inhibitor candidates. Thirteen new compounds based on benzoxazole moiety were synthesized and evaluated against three [...] Read more.

This work is one of our efforts to discover potent anticancer agents. We modified the most promising derivative of our previous work concerned with the development of VEGFR-2 inhibitor candidates. Thirteen new compounds based on benzoxazole moiety were synthesized and evaluated against three human cancer cell lines, namely, breast cancer (MCF-7), colorectal carcinoma (HCT116), and hepatocellular carcinoma (HepG2). The synthesized compounds were also evaluated against VEGFR-2 kinase activity. The biological testing fallouts showed that compound 8d was more potent than standard sorafenib. Such compound showed IC₅₀ values of 3.43, 2.79, and 2.43 µM against the aforementioned cancer cell lines, respectively, compared to IC₅₀ values of 4.21, 5.30, and 3.40 µM reported for sorafenib. Compound 8d also was found to exert exceptional VEGFR-2 inhibition activity with an IC₅₀ value of 0.0554 μM compared to sorafenib (0.0782 μM). In addition, compound 8h revealed excellent cytotoxic effects with IC₅₀ values of 3.53, 2.94, and 2.76 µM against experienced cell lines, respectively. Furthermore, compounds 8a and 8e were found to inhibit VEGFR-2 kinase activity with IC₅₀ values of 0.0579 and 0.0741 μM, exceeding that of sorafenib. Compound 8d showed a significant apoptotic effect and arrested the HepG2 cells at the pre-G1 phase. In addition, it exerted a significant inhibition for TNF-α (90.54%) and of IL-6 (92.19%) compared to dexamethasone (93.15%). The molecular docking studies showed that the binding pattern of the new compounds to VEGFR-2 kinase was similar to that of sorafenib. Full article

(This article belongs to the Special Issue Recent Advances in Carbohydrates, Glycosides, and Nucleosides for Biological and Computational Research)

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11 pages, 1893 KiB

Open AccessArticle

A Universal Biofilm Reactor Sensor for the Determination of Biochemical Oxygen Demand of Different Water Areas

by Liang Wang, Huan Lv, Qian Yang, Yiliang Chen, Junjie Wei, Yiyuan Chen, Ci’en Peng, Changyu Liu, Xiaolong Xu and Jianbo Jia

Molecules 2022, 27(15), 5046; https://doi.org/10.3390/molecules27155046 - 08 Aug 2022

Cited by 3 | Viewed by 1401

Abstract

In this study, we developed a simple strategy to prepare a biofilm reactor (BFR) sensor for the universal biochemical oxygen demand (BOD) determination. The microorganisms in fresh water were domesticated by artificial seawater with different salinity gradients successively to prepare the BFR sensor. [...] Read more.

In this study, we developed a simple strategy to prepare a biofilm reactor (BFR) sensor for the universal biochemical oxygen demand (BOD) determination. The microorganisms in fresh water were domesticated by artificial seawater with different salinity gradients successively to prepare the BFR sensor. The prepared BFR sensor exhibits an efficient ability to degrade a variety of organic substances. The linear range of BOD determination by the BFR sensor is 1.0–10.0 mg/L⁻¹ with a correlation coefficient of 0.9951. The detection limit is 0.30 mg/L according to three times of signal-to-noise ratio. What is more, the BFR sensor displayed excellent performances for the BOD determination of different water samples, including both fresh water and seawater. The 16S-rRNA gene sequencing technology was used to analyze the microbial species before and after the domestication. The results show that it is a general approach for the rapid BOD determination in different water samples. Full article

(This article belongs to the Special Issue Recent Advances in Functional Nanomaterials for Electrochemical Sensors and Biosensors)

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26 pages, 3141 KiB

Open AccessArticle

Isolation and Characterization of Galloylglucoses Effective against Multidrug-Resistant Strains of Escherichia coli and Klebsiella pneumoniae

by Nelson E. Masota, Knut Ohlsen, Curd Schollmayer, Lorenz Meinel and Ulrike Holzgrabe

Molecules 2022, 27(15), 5045; https://doi.org/10.3390/molecules27155045 - 08 Aug 2022

Cited by 5 | Viewed by 1938

Abstract

The search for new antibiotics against multidrug-resistant (MDR), Gram-negative bacteria is crucial with respect to filling the antibiotics development pipeline, which is subject to a critical shortage of novel molecules. Screening of natural products is a promising approach for identifying antimicrobial compounds hosting [...] Read more.

The search for new antibiotics against multidrug-resistant (MDR), Gram-negative bacteria is crucial with respect to filling the antibiotics development pipeline, which is subject to a critical shortage of novel molecules. Screening of natural products is a promising approach for identifying antimicrobial compounds hosting a higher degree of novelty. Here, we report the isolation and characterization of four galloylglucoses active against different MDR strains of Escherichia coli and Klebsiella pneumoniae. A crude acetone extract was prepared from Paeonia officinalis Linnaeus leaves, and bioautography-guided isolation of active compounds from the extract was performed by liquid–liquid extraction, as well as open column, flash, and preparative chromatographic methods. Isolated active compounds were characterized and elucidated by a combination of spectroscopic and spectrometric techniques. In vitro antimicrobial susceptibility testing was carried out on E. coli and K. pneumoniae using 2 reference strains and 13 strains hosting a wide range of MDR phenotypes. Furthermore, in vivo antibacterial activities were assessed using Galleria mellonella larvae, and compounds 1,2,3,4,6-penta-O-galloyl-β-d-glucose, 3-O-digalloyl-1,2,4,6-tetra-O-galloyl-β-d-glucose, 6-O-digalloyl-1,2,3,4-tetra-O-galloyl-β-d-glucose, and 3,6-bis-O-digalloyl-1,2,4-tri-O-galloyl-β-d-glucose were isolated and characterized. They showed minimum inhibitory concentration (MIC) values in the range of 2–256 µg/mL across tested bacterial strains. These findings have added to the number of known galloylglucoses from P. officinalis and highlight their potential against MDR Gram-negative bacteria. Full article

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15 pages, 3027 KiB

Open AccessArticle

Sunlight Induced and Recyclable g-C₃N₄ Catalyzed C-H Sulfenylation of Quinoxalin-2(1H)-Ones

by Sha Peng, Jiao Liu, Li-Hua Yang and Long-Yong Xie

Molecules 2022, 27(15), 5044; https://doi.org/10.3390/molecules27155044 - 08 Aug 2022

Cited by 6 | Viewed by 1577

Abstract

A sunlight-promoted sulfenylation of quinoxalin-2(1H)-ones using recyclable graphitic carbon nitride (g-C₃N₄) as a heterogeneous photocatalyst was developed. Using the method, various 3-sulfenylated quinoxalin-2(1H)-ones were obtained in good to excellent yields under an ambient air atmosphere. [...] Read more.

A sunlight-promoted sulfenylation of quinoxalin-2(1H)-ones using recyclable graphitic carbon nitride (g-C₃N₄) as a heterogeneous photocatalyst was developed. Using the method, various 3-sulfenylated quinoxalin-2(1H)-ones were obtained in good to excellent yields under an ambient air atmosphere. Moreover, the heterogeneous catalyst can be recycled at least six times without significant loss of activity. Full article

(This article belongs to the Special Issue Feature Papers in Organic Chemistry)

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27 pages, 2194 KiB

Open AccessReview

The Potential of Lamiaceae Herbs for Mitigation of Overweight, Obesity, and Fatty Liver: Studies and Perspectives

by Farah Diab, Hawraa Zbeeb, Francesca Baldini, Piero Portincasa, Mohamad Khalil and Laura Vergani

Molecules 2022, 27(15), 5043; https://doi.org/10.3390/molecules27155043 - 08 Aug 2022

Cited by 5 | Viewed by 3528

Abstract

Numerous plants, plant extracts, and plant-derived compounds are being explored for their beneficial effects against overweight and liver diseases. Obesity is associated with the increased prevalence of non-alcoholic fatty liver disease (NAFLD), becoming the most common liver disease in Western countries. Obesity and [...] Read more.

Numerous plants, plant extracts, and plant-derived compounds are being explored for their beneficial effects against overweight and liver diseases. Obesity is associated with the increased prevalence of non-alcoholic fatty liver disease (NAFLD), becoming the most common liver disease in Western countries. Obesity and NAFLD are closely associated with many other metabolic alternations such as insulin resistance, diabetes mellitus, and cardiovascular diseases. Many herbs of the Lamiaceae family are widely employed as food and spices in the Mediterranean area, but also in folk medicine, and their use for the management of metabolic disorders is well documented. Hereby, we summarized the scientific results of the medicinal and nutraceutical potential of plants from the Lamiaceae family for prevention and mitigation of overweight and fatty liver. The evidence indicates that Lamiaceae plants may be a cost-effective source of nutraceuticals and/or phytochemicals to be used in the management of metabolic-related conditions such as obesity and NAFLD. PubMed, Google Scholar, Scopus, and SciFinder were accessed to collect data on traditional medicinal plants, compounds derived from plants, their reported anti-obesity mechanisms, and therapeutic targets. Full article

(This article belongs to the Special Issue The Role of Natural Products in Promoting Well-being: From Foods to Drugs)

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10 pages, 3420 KiB

Open AccessArticle

Targeting Glutaminase by Natural Compounds: Structure-Based Virtual Screening and Molecular Dynamics Simulation Approach to Suppress Cancer Progression

by Shams Tabrez, Torki A. Zughaibi, Mehboob Hoque, Mohd Suhail, Mohammad Imran Khan and Azhar U. Khan

Molecules 2022, 27(15), 5042; https://doi.org/10.3390/molecules27155042 - 08 Aug 2022

Cited by 8 | Viewed by 1980 | Correction

Abstract

Cancer cells change their glucose and glutamine (GLU) metabolism to obtain the energy required to continue growing. Glutaminase (GLS) plays a crucial role in promoting cell metabolism for cancer cell growth; targeting GLU metabolism by inhibiting GLS has attracted interest as a potential [...] Read more.

Cancer cells change their glucose and glutamine (GLU) metabolism to obtain the energy required to continue growing. Glutaminase (GLS) plays a crucial role in promoting cell metabolism for cancer cell growth; targeting GLU metabolism by inhibiting GLS has attracted interest as a potential cancer management strategy. Herein, we employed a sequential screening of traditional Chinese medicine (TCM) database followed by drug-likeness and molecular dynamics simulations against the active site of GLS. We report 12 potent compounds after screening the TCM database against GLS, followed by a drug-likeness filter with Lipinski and Veber rule criteria. Among them, ZINC03978829 and ZINC32296657 were found to have higher binding energy (BE) values than the control compound 6-Diazo-5-Oxo-L-Norleucine, with BEs of −9.3 and −9.7 kcal/mol, respectively, compared to the BE of 6-Diazo-5-Oxo-L-Norleucine (−4.7 kcal/mol) with GLS. Molecular dynamics simulations were used to evaluate the results further, and a 100 ns MD simulation revealed that the hits form stable complexes with GLS and formed 2–5 hydrogen bond interactions. This study indicates that these hits might be employed as GLS inhibitors in the battle against cancer. However, more laboratory tests are a prerequisite to optimize them as GLS inhibitors. Full article

(This article belongs to the Special Issue Molecular Simulations Applications in Biochemistry and Molecular Biology)

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15 pages, 4079 KiB

Open AccessArticle

Antibacterial Activity of Aureonuclemycin Produced by Streptomyces aureus Strain SPRI-371

by Weiguo Wang, Minkang Feng, Xiaomeng Li, Feiyu Chen, Zhihao Zhang, Wenlong Yang, Chen Shao, Liming Tao and Yang Zhang

Molecules 2022, 27(15), 5041; https://doi.org/10.3390/molecules27155041 - 08 Aug 2022

Cited by 2 | Viewed by 1641

Abstract

Actinomycetes play a vital role as one of the most important natural resources for both pharmaceutical and agricultural applications. The actinomycete strain SPRI-371, isolated from soil collected in Jiangsu province, China, was classified as Streptomyces aureus based on its morphological, physiological, biochemical and [...] Read more.

Actinomycetes play a vital role as one of the most important natural resources for both pharmaceutical and agricultural applications. The actinomycete strain SPRI-371, isolated from soil collected in Jiangsu province, China, was classified as Streptomyces aureus based on its morphological, physiological, biochemical and molecular biological characteristics. Its bacterial activity metabolites were identified as aureonuclemycin (ANM), belonging to adenosine derivatives with the molecular formula C₁₆H₁₉N₅O₉ for ANM A and C₁₀H₁₃N₅O₃ for ANM B. Simultaneously, the industrial fermentation process of a mutated S. aureus strain SPRI-371 was optimized in a 20 m³ fermentation tank, featuring a rotation speed of 170 rpm, a pressure of 0.05 MPa, an inoculum age of 36–40 h and a dissolved oxygen level maintained at 1–30% within 40–80 h and at >60% in the later period, resulting in an ANM yield of >3700 mg/L. In the industrial separation of fermentation broth, the sulfuric acid solution was selected to adjust pH and 4# resin was used for adsorption. Then, it was resolved with 20% ethanol solution and concentrated in a vacuum (60–65 °C), with excellent results. Antibacterial experiments showed that ANM was less active or inactive against Xanthomonas oryzae pv. oryzae, Xanthomonas citri subsp. citri and Xanthomonas oryzae pv. oryzicola and most bacteria, yeast and fungi in vitro. However, in vivo experiments showed that ANM exhibited extremely significant protective and therapeutic activity against diseases caused by X. oryzae pv. oryzae and X. oryzae pv. oryzicola in rice and X. citri in oranges and lemons. In field trials, ANM A 150 gai/ha + ANM B 75 gai/ha exhibited excellent therapeutic activity against rice bacterial leaf blight, citrus canker and rice bacterial leaf streak. Furthermore, as the dosage and production cost of ANM are lower than those of commercial drugs, it has good application prospects. Full article

(This article belongs to the Special Issue Natural Products as Sources for Pesticides)

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10 pages, 1784 KiB

Open AccessArticle

Terahertz Spectroscopic Analysis of Lactose in Infant Formula: Implications for Detection and Quantification

by Sopanant Datta, Kiattiwut Prasertsuk, Nuttawat Khammata, Patharakorn Rattanawan, Jia Yi Chia, Rungroj Jintamethasawat, Thawatchart Chulapakorn and Taweetham Limpanuparb

Molecules 2022, 27(15), 5040; https://doi.org/10.3390/molecules27155040 - 08 Aug 2022

Cited by 1 | Viewed by 2129

Abstract

Lactose plays a significant role in daily lives as a constituent of various food and pharmaceutical products. Yet, lactose intolerance conditions demand low-lactose and lactose-free products in the market. These increasing nutritional claims and labels on food products entail simple and reliable methods [...] Read more.

Lactose plays a significant role in daily lives as a constituent of various food and pharmaceutical products. Yet, lactose intolerance conditions demand low-lactose and lactose-free products in the market. These increasing nutritional claims and labels on food products entail simple and reliable methods of analysis that can be used for meeting quality standards, nutritional claims and legal requirements. In this study, terahertz time–domain spectroscopy (THz-TDS) was employed to analyse α-lactose monohydrate qualitatively and quantitatively in food products. Both absorption spectra and absorption coefficient spectra were investigated for their prediction performance. Regression models for lactose quantification using peak area and height of the absorption peaks 0.53 and 1.37 THz were developed and assessed in infant formula samples. Satisfactory prediction results were achieved in ideal conditions with pure standards, but not in all predictions of infant formula samples. Reasons and further implications are discussed. Full article

(This article belongs to the Section Molecular Structure)

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13 pages, 1696 KiB

Open AccessArticle

A Strategy for Sample Preparation: Using Egg White Gel to Promote the Determination of Aflatoxin M1 Content in Milk Samples

by Xiao Ning, Lulu Wang, Shaoming Jin, Xuran Fu, Xiulan Sun and Jin Cao

Molecules 2022, 27(15), 5039; https://doi.org/10.3390/molecules27155039 - 08 Aug 2022

Cited by 2 | Viewed by 1448

Abstract

The analysis of food samples is a challenging task. The high complexity of food matrices hinders the extraction and detection of analytes from them. Therefore, the correct preparation of food samples is a crucial step for their subsequent analysis, as it achieves the [...] Read more.

The analysis of food samples is a challenging task. The high complexity of food matrices hinders the extraction and detection of analytes from them. Therefore, the correct preparation of food samples is a crucial step for their subsequent analysis, as it achieves the proper isolation and preconcentration of analytes and removes the interfering proportion of the food matrix before instrumental analysis. We aimed to develop a method that not only satisfies the requirement of detecting trace compounds in complex matrices but also achieves a “greener” approach by reducing the use of organic solvents and non-degradable materials to minimize the health hazards posed to the operators as well as pollution to the environment. In this study, we prepared egg white as a concentrated gel and used this material for the biological purification of milk samples. After the milk protein was removed by acidification and salting, the residual amount of aflatoxin M1 in milk samples was quantitatively determined by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that the novel egg white purification method possessed advantages over the immunoaffinity technique used as the reference method in extraction recovery, sensitivity, repeatability, and operability. The limit of detection (LOD) was 0.001 μg/kg. In spiked samples containing 0.01 μg/kg to 2 μg/kg of AFM1, the average recovery was 88.3–94.7%, with a precision of 6.1–11.0%. Improved repeatability was obtained by significantly reducing the operation time and resource requirements compared with the immunoaffinity technique currently used internationally. This study provides a reference for the further improvement of the relevant international standards in place for the detection of aflatoxin M1 in milk. Full article

(This article belongs to the Special Issue Advances in Analytical Sample Preparation Using Sorbent/Solid Phase Materials as Extraction Media)

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22 pages, 2847 KiB

Open AccessArticle

Dihydroxyquingdainone Induces Apoptosis in Leukaemia and Lymphoma Cells via the Mitochondrial Pathway in a Bcl-2- and Caspase-3-Dependent Manner and Overcomes Resistance to Cytostatic Drugs In Vitro

by Jennifer Baas, Sebastian Bieringer, Corazon Frias, Jerico Frias, Carolina Soehnchen, Corinna Urmann, Steffi Ritter, Herbert Riepl and Aram Prokop

Molecules 2022, 27(15), 5038; https://doi.org/10.3390/molecules27155038 - 08 Aug 2022

Cited by 3 | Viewed by 2154

Abstract

Isatis tinctoria and its indigo dyes have already provided highly active anti-leukaemic lead compounds, with the focus mainly being on indirubin, whereas indigo itself is inactive. There are many more indigoids to find in this plant extract, for example, quingdainone, an indigoid derived [...] Read more.

Isatis tinctoria and its indigo dyes have already provided highly active anti-leukaemic lead compounds, with the focus mainly being on indirubin, whereas indigo itself is inactive. There are many more indigoids to find in this plant extract, for example, quingdainone, an indigoid derived from tryptanthrin. We present here a new synthesis of hitherto neglected substituted quingdainones, which is very necessary due to their poor solubility behaviour, and a structure-dependent anti-leukaemic activity study of a number of compounds. Substituted α-phenylaminoacrylic acid was synthesised by hydrogen sulfide extrusion from an analogue mercaptoacetic acid, available from the condensation of rhodanin and a substituted tryptanthrin. It is shown that just improving water solubility does not increase anti-leukaemic activity, since a quingdainone carboxylic acid is inactive compared to dihydroxyquingdainone. The most effective compound, dihydroxyquingdainone with an AC₅₀ of 7.5 µmole, is further characterised, revealing its ability to overcome multidrug resistance in leukaemia cells (Nalm-6/BeKa) with p-glycoprotein expression. Full article

(This article belongs to the Special Issue Natural Product-Inspired Molecules: From Weed to Remedy)

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14 pages, 3801 KiB

Open AccessArticle

Sophorolipid Suppresses LPS-Induced Inflammation in RAW264.7 Cells through the NF-κB Signaling Pathway

by Ruiqi Xu, Ling Ma, Timson Chen and Jing Wang

Molecules 2022, 27(15), 5037; https://doi.org/10.3390/molecules27155037 - 08 Aug 2022

Cited by 16 | Viewed by 3668

Abstract

Objectives: Biosurfactants with anti-inflammatory activity may alleviate skin irritation caused by synthetic surfactants in cleaning products. Sophorolipid (SL) is a promising alternative to synthetic surfactants. However, there are few reports on the anti-inflammatory activity of SL and the underlying mechanism. The purpose of [...] Read more.

Objectives: Biosurfactants with anti-inflammatory activity may alleviate skin irritation caused by synthetic surfactants in cleaning products. Sophorolipid (SL) is a promising alternative to synthetic surfactants. However, there are few reports on the anti-inflammatory activity of SL and the underlying mechanism. The purpose of this work is to verify that lipopolysaccharide (LPS)-induced inflammation could be inhibited through targeting the pathway of nuclear factor-κB (NF-κB) in RAW264.7 cells. Methods: The influence of SL on cytokine release was investigated by LPS-induced RAW264.7 cells using ELISA. The quantification of the protein expression of corresponding molecular markers was realized by Western blot analysis. Flow cytometry was employed to determine the levels of Ca²⁺ and reactive oxygen species (ROS). The relative expression of inducible nitric oxide synthase (INOS) and cyclooxygenase-2 (COX-2) was determined by RT-PCR. An immunofluorescence assay and confocal microscope were used to observe the NF-κB/p65 translocation from the cytoplasm into the nucleus. The likely targets of SL were predicted by molecular docking analysis. Results: SL showed anti-inflammatory activity and reduced the release of inflammatory cytokines including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nitric oxide (NO). The experimental results show that SL suppressed the Ca²⁺ and ROS levels influx in the LPS-induced RAW264.7 cells and alleviated the LPS-induced expression of iNOS and COX-2, the LPS-induced translocation of NF-κB (p65) from the cytoplasm into the nucleus, and the expression of phosphorylated proteins such as p65 and IκBα. Furthermore, molecular docking analysis showed that SL may inhibit inflammatory signaling by competing with LPS to bind TLR4/MD-2 through hydrophobic interactions and by inhibiting IKKβ activation through the hydrogen bonding and hydrophobic interactions. Conclusion: This study demonstrated that SL exerted anti-inflammatory activity via the pathway of NF-κB in RAW264.7 cells. Full article

(This article belongs to the Special Issue Bioactive Lipids in Inflammatory Diseases)

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28 pages, 2796 KiB

Open AccessArticle

Why Ortho- and Para-Hydroxy Metabolites Can Scavenge Free Radicals That the Parent Atorvastatin Cannot? Important Pharmacologic Insight from Quantum Chemistry

by Ioan Bâldea

Molecules 2022, 27(15), 5036; https://doi.org/10.3390/molecules27155036 - 08 Aug 2022

Cited by 4 | Viewed by 1622

Abstract

The pharmaceutical success of atorvastatin (ATV), a widely employed drug against the “bad” cholesterol (LDL) and cardiovascular diseases, traces back to its ability to scavenge free radicals. Unfortunately, information on its antioxidant properties is missing or unreliable. Here, we report detailed quantum chemical [...] Read more.

The pharmaceutical success of atorvastatin (ATV), a widely employed drug against the “bad” cholesterol (LDL) and cardiovascular diseases, traces back to its ability to scavenge free radicals. Unfortunately, information on its antioxidant properties is missing or unreliable. Here, we report detailed quantum chemical results for ATV and its ortho- and para-hydroxy metabolites (o-ATV, p-ATV) in the methanolic phase. They comprise global reactivity indices, bond order indices, and spin densities as well as all relevant enthalpies of reaction (bond dissociation BDE, ionization IP and electron attachment EA, proton detachment PDE and proton affinity PA, and electron transfer ETE). With these properties in hand, we can provide the first theoretical explanation of the experimental finding that, due to their free radical scavenging activity, ATV hydroxy metabolites rather than the parent ATV, have substantial inhibitory effect on LDL and the like. Surprisingly (because it is contrary to the most cases currently known), we unambiguously found that HAT (direct hydrogen atom transfer) rather than SPLET (sequential proton loss electron transfer) or SET-PT (stepwise electron transfer proton transfer) is the thermodynamically preferred pathway by which o-ATV and p-ATV in methanolic phase can scavenge DPPH

^{•}

(1,1-diphenyl-2-picrylhydrazyl) radicals. From a quantum chemical perspective, the ATV’s species investigated are surprising because of the nontrivial correlations between bond dissociation energies, bond lengths, bond order indices and pertaining stretching frequencies, which do not fit the framework of naive chemical intuition. Full article

(This article belongs to the Special Issue A Commemorative Special Issue Honoring Professor Donald Truhlar)

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15 pages, 3203 KiB

Open AccessArticle

Anti-Inflammatory Activity of 4-(4-(Heptyloxy)phenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one via Repression of MAPK/NF-κB Signaling Pathways in β-Amyloid-Induced Alzheimer’s Disease Models

by Fengmao An, Xinran Xuan, Zheng Liu, Ming Bian, Qingkun Shen, Zheshan Quan, Guowei Zhang and Chengxi Wei

Molecules 2022, 27(15), 5035; https://doi.org/10.3390/molecules27155035 - 08 Aug 2022

Cited by 6 | Viewed by 1730

Abstract

Alzheimer’s disease (AD) is a major neurodegenerative disease, but so far, it can only be treated symptomatically rather than changing the process of the disease. Recently, triazoles and their derivatives have been shown to have potential for the treatment of AD. In this [...] Read more.

Alzheimer’s disease (AD) is a major neurodegenerative disease, but so far, it can only be treated symptomatically rather than changing the process of the disease. Recently, triazoles and their derivatives have been shown to have potential for the treatment of AD. In this study, the neuroprotective effects of 4-(4-(heptyloxy)phenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one (W112) against β-amyloid (Aβ)-induced AD pathology and its possible mechanism were explored both in vitro and in vivo. The results showed that W112 exhibits a neuroprotective role against Aβ-induced cytotoxicity in PC12 cells and improves the learning and memory abilities of Aβ-induced AD-like rats. In addition, the assays of the protein expression revealed that W112 reversed tau hyperphosphorylation and reduced the production of proinflammatory cytokines, tumor necrosis factor-α and interleukin-6, both in vitro and in vivo studies. Further study indicated that the regulation of mitogen-activated protein kinase/nuclear factor-κB pathways played a key role in mediating the neuroprotective effects of W112 against AD-like pathology. W112 may become a potential drug for AD intervention. Full article

(This article belongs to the Section Medicinal Chemistry)

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15 pages, 3180 KiB

Open AccessArticle

Photo-Protective and Anti-Inflammatory Effects of Antidesma thwaitesianum Müll. Arg. Fruit Extract against UVB-Induced Keratinocyte Cell Damage

by Sutthibhon Natewong, Cholticha Niwaspragrit, Piyanee Ratanachamnong, Papavee Samatiwat, Poommaree Namchaiw and Yamaratee Jaisin

Molecules 2022, 27(15), 5034; https://doi.org/10.3390/molecules27155034 - 08 Aug 2022

Cited by 5 | Viewed by 2020

Abstract

The main cause of most skin cancers is damage from UVB from sunlight, which penetrate the skin surface and induce inflammation. For this reason, this study aims to identify natural products with photo-protection properties and their mode of action by using the UVB-irradiated [...] Read more.

The main cause of most skin cancers is damage from UVB from sunlight, which penetrate the skin surface and induce inflammation. For this reason, this study aims to identify natural products with photo-protection properties and their mode of action by using the UVB-irradiated HaCaT keratinocyte model. Antidesma thwaitesianum fruit extracts at 25, 50, and 100 µg/mL recovered cell viability following UVB exposure in a dose-dependent manner. Cell survival was associated with the reduction in intracellular ROS and NO. In addition, we showed that the pre-treatment with the fruit extract lowered the phosphorylation level of two MAPK-signaling pathways: p38 MAPKs and JNKs. The resulting lower MAPK activation decreased their downstream pro-inflammatory cascade through COX-2 expression and subsequently reduced the PGE₂ proinflammatory mediator level. The photoprotective effects of the fruit extract were correlated with the presence of polyphenolic compounds, including cyanidin, ferulic acid, caffeic acid, vanillic acid, and protocatechuic acid, which have been previously described as antioxidant and anti-inflammation. Together, we demonstrated that the pre-treatment with the fruit extract had photo-protection by inhibiting oxidative stress and subsequently lowered stress-induced MAPK responses. Therefore, this fresh fruit is worthy of investigation to be utilized as a skincare ingredient for preventing UVB-induced skin damage. Full article

(This article belongs to the Special Issue Antioxidant Capacity of Phytochemicals in Fruits and Vegetables)

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11 pages, 2120 KiB

Open AccessArticle

Cookies Fortified with Lonicera japonica Thunb. Extracts: Impact on Phenolic Acid Content, Antioxidant Activity and Physical Properties

by Weiwei Cao, Junliang Chen, Linlin Li, Guangyue Ren, Xu Duan, Qian Zhou, Mengli Zhang, Danping Gao, Shanshan Zhang and Xu Liu

Molecules 2022, 27(15), 5033; https://doi.org/10.3390/molecules27155033 - 08 Aug 2022

Cited by 6 | Viewed by 1696

Abstract

Lonicera japonica Thunb [...] Full article

(This article belongs to the Special Issue Plant Foods Ingredients as Functional Foods and Nutraceuticals)

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17 pages, 2216 KiB

Open AccessArticle

Mechanism of the Micellar Solubilization of Curcumin by Mixed Surfactants of SDS and Brij35 via NMR Spectroscopy

by Xiao Zhan, Zhaoxia Wu, Zhong Chen and Xiaohong Cui

Molecules 2022, 27(15), 5032; https://doi.org/10.3390/molecules27155032 - 08 Aug 2022

Cited by 7 | Viewed by 2194

Abstract

The micellar solubilization mechanism of curcumin by mixed surfactants of SDS and Brij35 was investigated at the molecular scale by NMR spectroscopy. Through the investigation of the micelle formation process, types and structures of mixed micelles and solubilization sites, the intrinsic factors influencing [...] Read more.

The micellar solubilization mechanism of curcumin by mixed surfactants of SDS and Brij35 was investigated at the molecular scale by NMR spectroscopy. Through the investigation of the micelle formation process, types and structures of mixed micelles and solubilization sites, the intrinsic factors influencing the solubilization capacity were revealed. For systems with α_SDS = 0.5 and 0.2, the obtained molar solubilization ratios (MSRs) are consistent with the MSR_ideal values. However, for α_SDS = 0.8, the solubilization capacity of curcumin is weakened compared to the MSR_ideal. Furthermore, only one single mixed SDS/Brij35 micelles are formed for α_SDS = 0.5 and 0.2. However, for α_SDS = 0.8, there are separate SDS-rich and Brij35-rich mixed micelles formed. In addition, NOESY spectra show that the interaction patterns of SDS and Brij35 in mixed micelles are similar for three systems, as are the solubilization sites of curcumin. Therefore, for α_SDS = 0.5 and 0.2 with single mixed micelles formed, the solubility of curcumin depends only on the mixed micelle composition, which is almost equal to the surfactant molar ratio. Although curcumin is solubilized in both separate micelles at α_SDS = 0.8, a less stable micelle structure may be responsible for the low solubility. This study provides new insights into the investigation and application of mixed micelle solubilization. Full article

(This article belongs to the Special Issue Exclusive Feature Papers in Physical Chemistry)

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15 pages, 3647 KiB

Open AccessArticle

Counteractive Effects of Choline Geranate (CAGE) ILs and Ethanol on Insulin’s Stability—A Leap Forward towards Oral Insulin Formulation

by Kandhan Palanisamy and Muthuramalingam Prakash

Molecules 2022, 27(15), 5031; https://doi.org/10.3390/molecules27155031 - 08 Aug 2022

Cited by 1 | Viewed by 1660

Abstract

Choline geranate (CAGE) ionic liquids (ILs) stabilize insulin, thereby aiding its oral delivery, whereas ethanol (EtOH) affects its stability by disrupting the hydrophobic interactions. In this study, cognizance of the stabilization mechanism of insulin dimer in the presence of both CAGE ILs and [...] Read more.

Choline geranate (CAGE) ionic liquids (ILs) stabilize insulin, thereby aiding its oral delivery, whereas ethanol (EtOH) affects its stability by disrupting the hydrophobic interactions. In this study, cognizance of the stabilization mechanism of insulin dimer in the presence of both CAGE ILs and EtOH mixtures is achieved through biased and unbiased molecular dynamics (MD) simulations. Here, two order parameters are employed to study the insulin dimer dissociation using well-tempered metadynamics (WT-MetaD). The stability of insulin is found to be strongly maintained until a 0.20 mole fraction of EtOH. Besides, higher concentrations of EtOH marginally affect the insulin stability. Moreover, geranate anions form a higher number of H-bonding interactions with water molecules, which aids insulin stabilization. Conversely, the addition of EtOH minimizes the water-mediated H-bonding interactions of geranate. Additionally, geranate traps the EtOH molecules, thereby preventing the interactions between insulin and EtOH. Furthermore, the free energy landscape (FEL) reveals the absence of dimer dissociation along with noticeable deviations in the distances R and the number of contacts Q. The dimerization free energy of insulin was calculated to be −16.1 kcal/mol at a 0.20 mole fraction of EtOH. Moreover, increments in mole fractions of EtOH effectuate a decrease in the insulin stability. Thus, the present study represents CAGE ILs as efficient insulin dimer stabilizes at low concentrations of EtOH. Full article

(This article belongs to the Special Issue Feature Papers in Chemical Biology—Edition of 2022-2023)

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14 pages, 1947 KiB

Open AccessArticle

Stability and Antiproliferative Activity of Malvidin-Based Non-Oxonium Derivative (Oxovitisin A) Compared with Precursor Anthocyanins and Pyranoanthocyanins

by Muci Wu, Yan Ma, Ao Li, Jingyi Wang, Jingren He and Rui Zhang

Molecules 2022, 27(15), 5030; https://doi.org/10.3390/molecules27155030 - 07 Aug 2022

Cited by 3 | Viewed by 1575

Abstract

Oxovitisins are a unique group of anthocyanin derivatives with a non-oxonium nature and α-pyranone (lactone) D ring on the structure. In this study, oxovitisin A was synthesized through the micro-oxidative reaction of carboxypyranomalvidin-3-O-glucoside (vitisin A) with water, and its thermostability, pH, and SO [...] Read more.

Oxovitisins are a unique group of anthocyanin derivatives with a non-oxonium nature and α-pyranone (lactone) D ring on the structure. In this study, oxovitisin A was synthesized through the micro-oxidative reaction of carboxypyranomalvidin-3-O-glucoside (vitisin A) with water, and its thermostability, pH, and SO₂ color stability were studied compared with its two precursors, malvidin-3-O-glucoside (Mv3glc) and vitisin A, as well as methylpyrano-malvidin-3-O-glucoside (Me-py). Results showed that oxovitisin A exhibited the highest stabilities, which were inseparably related to its noncharged structure and the additional carbonyl group on the D ring. Moreover, the antiproliferative capacity of oxovitisin A was comparatively evaluated against two human gastrointestinal cancer cell lines. Interestingly, oxovitisin A presented the strongest antiproliferative ability on MKN-28 (IC₅₀ = 538.42 ± 50.06 μM) and Caco-2 cells (IC₅₀ = 434.85 ± 11.87 μM) compared with two other pyranoanthocyanins. Therefore, we conclude that oxovitisin A as a highly stable anthocyanin derivative still exhibits a satisfactory antiproliferative ability. Full article

(This article belongs to the Special Issue Anthocyanins: Extraction, Purification and Applications)

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13 pages, 3590 KiB

Open AccessArticle

Identification of Novel 4′-O-Demethyl-epipodophyllotoxin Derivatives as Antitumor Agents Targeting Topoisomerase II

by Wenli Xi, Hua Sun, Kenneth F. Bastow, Zhiyan Xiao and Kuo-Hsiung Lee

Molecules 2022, 27(15), 5029; https://doi.org/10.3390/molecules27155029 - 07 Aug 2022

Cited by 3 | Viewed by 1505

Abstract

C4 variation of 4′-O-demethyl-epipodophyllotoxin (DMEP) is an effective approach to optimize the antitumor spectra of this compound class. Accordingly, two series of novel DMEP derivatives were synthesized, and as expected, the antitumor spectra of these derivatives varied with different C4 substituents. [...] Read more.

C4 variation of 4′-O-demethyl-epipodophyllotoxin (DMEP) is an effective approach to optimize the antitumor spectra of this compound class. Accordingly, two series of novel DMEP derivatives were synthesized, and as expected, the antitumor spectra of these derivatives varied with different C4 substituents. Notably, most compounds showed significant inhibition against the etoposide (2)-resistant KBvin cells. Four of the compounds (11, 18, 27 and 28) induced protein-linked DNA break (PLDB) levels higher than those of GL-331 (6) and 2, and are assumed to be topoisomerase II (topo II) poisons more potent than 6 and 2. Compound 28, a potent topo II poison highly effective against KBvin cells, was further evaluated with a panel of tumor cells and was most active against HepG2. This compound also exhibited apparent in vivo antitumor efficacy in hepatoma 22 (H22) mouse model. The results indicated that C4 derivation of DMEP is a feasible approach to identify potent topo II inhibitors with optimized antitumor profiles. Full article

(This article belongs to the Special Issue Natural Products as Sources of New Drugs: In Memory of Professor Kuo-Hsiung Lee (1940-2021))

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12 pages, 8835 KiB

Open AccessArticle

Facile Synthesis of Stable Cerium Dioxide Sols in Nonpolar Solvents

by Alexander E. Baranchikov, Mikhail I. Razumov, Svetlana V. Kameneva, Madina M. Sozarukova, Tatiana S. Beshkareva, Arina D. Filippova, Daniil A. Kozlov, Olga S. Ivanova, Alexander B. Shcherbakov and Vladimir K. Ivanov

Molecules 2022, 27(15), 5028; https://doi.org/10.3390/molecules27155028 - 07 Aug 2022

Cited by 4 | Viewed by 2342

Abstract

A method is proposed for the preparation of stable sols of nanocrystalline cerium dioxide in nonpolar solvents, based on surface modification of CeO₂ nanoparticles obtained by thermal hydrolysis of concentrated aqueous solutions of ammonium cerium(IV) nitrate with residues of 2-ethylhexanoic and octanoic [...] Read more.

A method is proposed for the preparation of stable sols of nanocrystalline cerium dioxide in nonpolar solvents, based on surface modification of CeO₂ nanoparticles obtained by thermal hydrolysis of concentrated aqueous solutions of ammonium cerium(IV) nitrate with residues of 2-ethylhexanoic and octanoic acids. The synthesis was carried out at temperatures below 100 °C and did not require the use of expensive and toxic reagents. An assessment of the radical-scavenging properties of the obtained sols using the superoxide anion-radical neutralization model revealed that they demonstrate notable antioxidant activity. The results obtained indicate the potential of the nanoscale cerium dioxide sols in nonpolar solvents to be used for creating nanobiomaterials possessing antioxidant properties. Full article

(This article belongs to the Special Issue Nanochemistry Today: Feature Papers from the Editorial Board)

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15 pages, 5625 KiB

Open AccessArticle

One Pot Synthesis of Graphene through Microwave Assisted Liquid Exfoliation of Graphite in Different Solvents

by Betül Gürünlü, Çiğdem Taşdelen-Yücedağ and Mahmut Bayramoğlu

Molecules 2022, 27(15), 5027; https://doi.org/10.3390/molecules27155027 - 07 Aug 2022

Cited by 4 | Viewed by 2086

Abstract

This study presents an easy and quick method for the synthesis of graphene from graphite in a set of solvents, including n-Hexadecane (n-Hexa), dimethylsulfoxide (DMSO), sodium hydroxide (NaOH), 1-octanol (OCTA), perchloric acid (PA), N,N-Dimethylformamide (DMF), ethylene glycol (EG), and ethylene diamine (ED), via [...] Read more.

This study presents an easy and quick method for the synthesis of graphene from graphite in a set of solvents, including n-Hexadecane (n-Hexa), dimethylsulfoxide (DMSO), sodium hydroxide (NaOH), 1-octanol (OCTA), perchloric acid (PA), N,N-Dimethylformamide (DMF), ethylene glycol (EG), and ethylene diamine (ED), via microwave (MW) energy. The properties of final products were determined by X-ray diffraction spectroscopy (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-Vis) spectroscopy, and the four-point probe technique. The XRD spectra of most of the MW-assisted graphene products showed peaks at 2θ = 26.5° and 54°. Layer numbers extend from 2 and 25, and the leading comes about were gotten by having two-layered products, named as graphene synthesized in dimethylsulfoxide (G-DMSO), graphene synthesized in ethylene glycol (G-EG), and graphene synthesized in 1-octanol (G-OCTA). G-DMF has the highest electrical conductivity with 22 S/m. The electrical conductivity is higher when the dipole moment of the used solvent is between 2 and 4 Debye (D). The FTIR spectra of most of the MW-assisted graphene products are in line with commercial graphene (CG). The UV-Vis spectra of all MW-assisted graphene products showed a peak at 223 nm referring to characteristic sp2 C=C bonds and 273 nm relating to the n → π * transition of C-O bonds. Full article

(This article belongs to the Special Issue 2D Nanomaterials and Nanostructures)

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18 pages, 5079 KiB

Open AccessArticle

Improved Metal Cation Optosensing Membranes through the Incorporation of Sulphated Polysaccharides

by P. R. M. Santos, A. Johny, C. Q. Silva, M. A. Azenha, J. A. Vázquez, J. Valcarcel, C. M. Pereira and A. F. Silva

Molecules 2022, 27(15), 5026; https://doi.org/10.3390/molecules27155026 - 07 Aug 2022

Cited by 2 | Viewed by 1373

Abstract

Optosensing chitosan-based membranes have been applied for the detection of heavy metals, especially in drinking water. The novelty of this study is based on the use of sulphated polysaccharides, in such optosensing membranes, aiming at an improved analytical performance. The sulphated polysaccharides, such [...] Read more.

Optosensing chitosan-based membranes have been applied for the detection of heavy metals, especially in drinking water. The novelty of this study is based on the use of sulphated polysaccharides, in such optosensing membranes, aiming at an improved analytical performance. The sulphated polysaccharides, such as ulvan, fucoidan and chondroitin sulfate, were extracted from by-products and wastes of marine-related activities. The membranes were developed for the analysis of aluminum. The variation in the visible absorbance of the sensor membranes after the contact between the chromophore and the aluminum cation was studied. The membranes containing sulphated polysaccharides showed improved signals when compared to the chitosan-only membrane. As for the detection limits for the membranes containing ulvan, fucoidan and chondroitin sulfate, 0.17 mg L⁻¹, 0.21 mg L⁻¹ and 0.36 mg L⁻¹ were obtained, respectively. The values were much lower than that obtained for the chitosan-only membrane, 0.52 mg L⁻¹, which shows the improvement obtained from the sulphated polysaccharides. The results were obtained with the presence of CTAB in analysis solution, which forms a ternary complex with the aluminum cation and the chromophore. This resulted in an hyperchromic and batochromic shift in the absorption band. When in the presence of this surfactant, the membranes showed lower detection limits and higher selectivity. Full article

(This article belongs to the Special Issue Porous Materials - Something Old, Something New)

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12 pages, 1249 KiB

Open AccessArticle

Rapid Simultaneous Quantification of 1-Formyl-2,2-Dimethylhydrazine and Dimethylurea Isomers in Environmental Samples by Supercritical Fluid Chromatography–Tandem Mass Spectrometry

by Denis V. Ovchinnikov, Sergey A. Vakhrameev, Danil I. Falev, Nikolay V. Ul’yanovskii and Dmitry S. Kosyakov

Molecules 2022, 27(15), 5025; https://doi.org/10.3390/molecules27155025 - 07 Aug 2022

Cited by 2 | Viewed by 1602

Abstract

When released to the environment, the rocket fuel unsymmetrical dimethylhydrazine (UDMH) undergoes oxidative transformations, resulting in the formation of an extremely large number of nitrogen-containing transformation products, including isomeric compounds which are difficult to discriminate by common chromatography techniques. In the present work, [...] Read more.

When released to the environment, the rocket fuel unsymmetrical dimethylhydrazine (UDMH) undergoes oxidative transformations, resulting in the formation of an extremely large number of nitrogen-containing transformation products, including isomeric compounds which are difficult to discriminate by common chromatography techniques. In the present work, supercritical fluid chromatography–tandem mass spectrometry (SFC-MS/MS) was proposed for resolving the problem of fast separation and simultaneous quantification of 1-formyl-2,2-dimethylhydrazine (FADMH) as one of the major UDMH transformation products, and its isomers—1,1-dimethylurea (UDMU) and 1,2-dimethylurea (SDMU). 2-Ethylpyridine stationary phase provided baseline separation of analytes in 1.5 min without the distortion of the chromatographic peaks. Optimization of SFC separation and MS/MS detection conditions allowed for the development of rapid, sensitive, and “green” method for the simultaneous determination of FADMH, UDMU, and SDMU in environmental samples with LOQs of 1–10 µg L⁻¹ and linear range covering three orders of magnitude. The method was validated and successfully tested on the real extracts of peaty and sandy soils polluted with rocket fuel and UDMH oxidation products. It was shown that both UDMU and SDMU are formed in noticeable amounts during UDMH oxidation. Despite relatively low toxicity, UDMU can be considered one of the major UDMH transformation products and a potential marker of soil pollution with toxic rocket fuel. Full article

(This article belongs to the Special Issue Chromatography—The Ultimate Analytical Tool II)

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18 pages, 3883 KiB

Open AccessArticle

Lipase-Catalyzed Synthesis, Antioxidant Activity, Antimicrobial Properties and Molecular Docking Studies of Butyl Dihydrocaffeate

by Bartłomiej Zieniuk, Chimaobi James Ononamadu, Karina Jasińska, Katarzyna Wierzchowska and Agata Fabiszewska

Molecules 2022, 27(15), 5024; https://doi.org/10.3390/molecules27155024 - 07 Aug 2022

Cited by 3 | Viewed by 1984

Abstract

Green chemistry approaches, such as lipase-catalyzed esterification, are promising methods for obtaining valuable chemical compounds. In the case of the use of lipases, unlike in aqueous environments, the processes of the ester bond formations are encountered in organic solvents. The aim of the [...] Read more.

Green chemistry approaches, such as lipase-catalyzed esterification, are promising methods for obtaining valuable chemical compounds. In the case of the use of lipases, unlike in aqueous environments, the processes of the ester bond formations are encountered in organic solvents. The aim of the current research was to carry out the lipase-catalyzed synthesis of an ester of dihydrocaffeic acid. The synthesized compound was then evaluated for antioxidant and antimicrobial activities. However, the vast majority of its antioxidant activity was retained, which was demonstrated by means of DPPH· (2,2-diphenyl-1-picrylhydrazyl) and CUPRAC (cupric ion reducing antioxidant capacity) methods. Regarding its antimicrobial properties, the antifungal activity against Rhizopus oryzae is worth mentioning. The minimum inhibitory and fungicidal concentrations were 1 and 2 mM, respectively. The high antifungal activity prompted the use of molecular docking studies to verify potential protein targets for butyl ester of dihydrocaffeic ester. In the case of one fungal protein, namely 14-α sterol demethylase B, it was observed that the ester had comparable binding energy to the triazole medication, isavuconazole, but the interacted amino acid residues were different. Full article

(This article belongs to the Special Issue Chemistry, Biology, and Pharmacology of Natural Phenolic Compounds and Their Synthetic Derivatives)

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14 pages, 1188 KiB

Open AccessArticle

Analysis of VOCs in Urine Samples Directed towards of Bladder Cancer Detection

by Tomasz Ligor, Przemysław Adamczyk, Tomasz Kowalkowski, Ileana Andreea Ratiu, Anna Wenda-Piesik and Bogusław Buszewski

Molecules 2022, 27(15), 5023; https://doi.org/10.3390/molecules27155023 - 07 Aug 2022

Cited by 10 | Viewed by 2065

Abstract

Bladder cancer is one of most common types of cancer diagnosed in the genitourinary tract. Typical tests are costly and characterized by low sensitivity, which contributes to a growing interest in volatile biomarkers. Head space solid phase microextraction (SPME) was applied for the [...] Read more.

Bladder cancer is one of most common types of cancer diagnosed in the genitourinary tract. Typical tests are costly and characterized by low sensitivity, which contributes to a growing interest in volatile biomarkers. Head space solid phase microextraction (SPME) was applied for the extraction of volatile organic compounds from urine samples, and gas chromatography time of flight mass spectrometry (GC×GC TOF MS) was used for the separation and detection of urinary volatiles. A cohort of 40 adult patients with bladder cancer and 57 healthy persons was recruited. Different VOC profiles were obtained for urine samples taken from each group. Twelvecompounds were found only in the samples from theBC group.The proposed candidate biomarkers are butyrolactone; 2-methoxyphenol; 3-methoxy-5-methylphenol; 1-(2,6,6-trimethylcyclohexa-1,3-dien-1-yl)-2-buten-1-one; nootkatone and 1-(2,6,6-trimethyl-1-cyclohexenyl)-2-buten-1-one.Since most of the studies published in the field are proving the potential of VOCs detected in urine samples for the screening and discrimination of patients with bladder cancer from healthy, but rarely presenting the identity of proposed biomarkers, our study represents a novel approach. Full article

(This article belongs to the Special Issue Recent Advances in Volatile Organic Compounds Analysis in Various Matrices)

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19 pages, 6409 KiB

Open AccessArticle

Manufacturing of Fluff Pulp Using Different Pulp Sources and Bentonite on an Industrial Scale for Absorbent Hygienic Products

by Saeed Ismaeilimoghadam, Mehdi Sheikh, Pouyan Taheri, Sadegh Maleki, Hossien Resalati, Mehdi Jonoobi, Bahareh Azimi and Serena Danti

Molecules 2022, 27(15), 5022; https://doi.org/10.3390/molecules27155022 - 07 Aug 2022

Cited by 4 | Viewed by 3729

Abstract

In this study, for the first time, a composite fluff pulp was produced based on the combination of softwood (i.e., long-length fiber), hardwood (i.e., short-length fiber), non-wooden pulps (i.e., bagasse) and bentonite, with specific amounts to be used in hygienic pads (e.g., baby [...] Read more.

In this study, for the first time, a composite fluff pulp was produced based on the combination of softwood (i.e., long-length fiber), hardwood (i.e., short-length fiber), non-wooden pulps (i.e., bagasse) and bentonite, with specific amounts to be used in hygienic pads (e.g., baby diapers and sanitary napkins). After the defibration process, the manufactured fluff pulp was placed as an absorbent mass in diapers and sanitary napkins. Therefore, tests related to the fluff pulp, such as grammage, thickness, density, ash content, humidity percentage, pH and brightness, tests related to the manufactured baby diapers, such as absorption capacity, retention rate, retention capacity, absorption time and rewet, and tests related to the sanitary napkin, such as absorption capacity and rewet, were performed according to the related standards. The results demonstrated that increasing the amount of bagasse pulp led to increasing the ash content, pH and density of fluff pulp and decreasing the brightness. The addition of bentonite as a filler also increased ash content and pH of fluff pulp. The results also demonstrated that increasing of bagasse pulp up to 30% in combination with softwood pulp led to increasing absorption capacity, retention rate, retention capacity, absorption time and rewet of baby diapers and of sanitary napkins. Full article

(This article belongs to the Special Issue Materials Chemistry in Italy)

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12 pages, 2128 KiB

Open AccessArticle

Construction of Co,N-Coordinated Carbon Dots for Efficient Oxygen Reduction Reaction

by Mengying Le, Bingjie Hu, Meiying Wu, Huazhang Guo and Liang Wang

Molecules 2022, 27(15), 5021; https://doi.org/10.3390/molecules27155021 - 07 Aug 2022

Cited by 12 | Viewed by 1780

Abstract

For the sake of the oxygen reduction reaction (ORR) catalytic performance, carbon dots (CDs) doped with metal atoms have accelerated their local electron flow for the past few years. However, the influence of CDs doped with metal atoms on binding sites and formation [...] Read more.

For the sake of the oxygen reduction reaction (ORR) catalytic performance, carbon dots (CDs) doped with metal atoms have accelerated their local electron flow for the past few years. However, the influence of CDs doped with metal atoms on binding sites and formation mechanisms is still uncertain. Herein, Co,N-doped CDs were facilely prepared by the low-temperature polymerization–solvent extraction strategy from EDTA-Co. The influence of Co doping on the catalytic performance of Co-CDs was explored, mainly in the following aspects: first, the pyridinic N atom content of Co-CDs significantly increased from 4.2 to 11.27 at% compared with the CDs, which indicates that the Co element in the precursor is advantageous in forming more pyridinic-N-active sites for boosting the ORR performance. Second, Co-CDs are uniformly distributed on the surface of carbon black (CB) to form Co-CDs@CB by the facile hydrothermal route, which can expose more active sites than the aggregation status. Third, the highest graphite N content of Co-CDs@CB was found, by limiting the current density of the catalyst towards the ORR. Composite nanomaterials formed by Co and CB are also used as air electrodes to manufacture high-performance zinc–air batteries. The battery has good cycle stability and realizes stable charges and discharges under different current densities. The outstanding catalytic activity of Co-CDs@CB is attributed to the Co,N synergistic effect induced by Co doping, which pioneer a new metal doping mechanism for gaining high-performance electrocatalysts. Full article

(This article belongs to the Special Issue Functional Carbon Quantum Dots: Synthesis and Applications)

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22 pages, 5040 KiB

Open AccessArticle

Microwave-Assisted Hydrothermal Rapid Synthesis of Ultralong Hydroxyapatite Nanowires Using Adenosine 5′-Triphosphate

by Yu Zhang, Ying-Jie Zhu and Han-Ping Yu

Molecules 2022, 27(15), 5020; https://doi.org/10.3390/molecules27155020 - 07 Aug 2022

Cited by 3 | Viewed by 1860

Abstract

Ultralong hydroxyapatite (HAP) nanowires are promising for various biomedical applications owing to their chemical similarity to the inorganic constituent of bone, high biocompatibility, good flexibility, excellent mechanical properties, etc. However, it is still challenging to control the formation of ultralong HAP nanowires because [...] Read more.

Ultralong hydroxyapatite (HAP) nanowires are promising for various biomedical applications owing to their chemical similarity to the inorganic constituent of bone, high biocompatibility, good flexibility, excellent mechanical properties, etc. However, it is still challenging to control the formation of ultralong HAP nanowires because of the presence of free PO₄³⁻ ions in the reaction system containing the inorganic phosphate source. In addition, it takes a long period of time (usually tens of hours) for the synthetic process of ultralong HAP nanowires. Herein, for the first time, we have developed an eco-friendly calcium oleate precursor microwave hydrothermal method using biocompatible adenosine 5′-triphosphate (ATP) as a bio-phosphorus source and water as the only solvent for the rapid synthesis of ultralong HAP nanowires. The controllable hydrolysis of ATP can avoid the premature formation of calcium phosphate nuclei and uncontrollable crystal growth. Microwave heating can significantly shorten the synthetic time from tens of hours required by the traditional heating to 1 h, thus achieving high efficiency, energy saving and low cost. The as-prepared ultralong HAP nanowires with high flexibility have lengths of several hundred micrometers and diameters of 10~20 nm, and they usually self-assemble into nanowire bundles along their longitudinal direction. The as-prepared ultralong HAP nanowire/chitosan porous scaffold has excellent bioactivity, good biodegradation and cytocompatibility owing to the bioactive adenosine adsorbed on the surface of ultralong HAP nanowires. It is expected that ultralong HAP nanowires will be promising for various applications in the biomedical fields, such as bone defect repair, skin wound healing, and as a drug nanocarrier. Full article

(This article belongs to the Topic Synthesis and Applications of Nanowires)

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23 pages, 1491 KiB

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All-Atom Molecular Dynamics of Pure Water–Methane Gas Hydrate Systems under Pre-Nucleation Conditions: A Direct Comparison between Experiments and Simulations of Transport Properties for the Tip4p/Ice Water Model

by André Guerra, Samuel Mathews, Milan Marić, Phillip Servio and Alejandro D. Rey

Molecules 2022, 27(15), 5019; https://doi.org/10.3390/molecules27155019 - 07 Aug 2022

Cited by 7 | Viewed by 2087

Abstract

(1) Background: New technologies involving gas hydrates under pre-nucleation conditions such as gas separations and storage have become more prominent. This has necessitated the characterization and modeling of the transport properties of such systems. (2) Methodology: This work explored methane hydrate systems under [...] Read more.

(1) Background: New technologies involving gas hydrates under pre-nucleation conditions such as gas separations and storage have become more prominent. This has necessitated the characterization and modeling of the transport properties of such systems. (2) Methodology: This work explored methane hydrate systems under pre-nucleation conditions. All-atom molecular dynamics simulations were used to quantify the performance of the TIP4P/2005 and TIP4P/Ice water models to predict the viscosity, diffusivity, and thermal conductivity using various formulations. (3) Results: Molecular simulation equilibrium was robustly demonstrated using various measures. The Green–Kubo estimation of viscosity outperformed other formulations when combined with TIP4P/Ice, and the same combination outperformed all TIP4P/2005 formulations. The Green–Kubo TIP4P/Ice estimation of viscosity overestimates (by 84% on average) the viscosity of methane hydrate systems under pre-nucleation conditions across all pressures considered (0–5 MPag). The presence of methane was found to increase the average number of hydrogen bonds over time (6.7–7.8%). TIP4P/Ice methane systems were also found to have 16–19% longer hydrogen bond lifetimes over pure water systems. (4) Conclusion: An inherent limitation in the current water force field for its application in the context of transport properties estimations for methane gas hydrate systems. A re-parametrization of the current force field is suggested as a starting point. Until then, this work may serve as a characterization of the deviance in viscosity prediction. Full article

(This article belongs to the Special Issue Exclusive Feature Papers in Physical Chemistry)

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