Molecules

20 pages, 871 KiB

Open AccessSystematic Review

Protease Produced by Endophytic Fungi: A Systematic Review

by Victor Hugo Souto Bezerra, Samuel Leite Cardoso, Yris Fonseca-Bazzo, Dâmaris Silveira, Pérola Oliveira Magalhães and Paula Monteiro Souza

Molecules 2021, 26(22), 7062; https://doi.org/10.3390/molecules26227062 - 22 Nov 2021

Cited by 10 | Viewed by 4301

Abstract

The purpose of this systematic review was to identify the available literature of production, purification, and characterization of proteases by endophytic fungi. There are few complete studies that entirely exhibit the production, characterization, and purification of proteases from endophytic fungi. This study followed [...] Read more.

The purpose of this systematic review was to identify the available literature of production, purification, and characterization of proteases by endophytic fungi. There are few complete studies that entirely exhibit the production, characterization, and purification of proteases from endophytic fungi. This study followed the PRISMA, and the search was conducted on five databases: PubMed, PMC, Science Direct, Scopus Articles, and Web of Science up until 18 May 2021, with no time or language restrictions. The methodology of the selected studies was evaluated using GRADE. Protease production, optimization, purification, and characterization were the main evaluated outcomes. Of the 5540 initially gathered studies, 15 met the inclusion criteria after a two-step selection process. Only two studies optimized the protease production using statistical design and two reported enzyme purification and characterization. The genus Penicillium and Aspergillus were the most cited among the eleven different genera of endophytic fungi evaluated in the selected articles. Six studies proved the ability of some endophytic fungi to produce fibrinolytic proteases, demonstrating that endophytic fungi can be exploited for the further production of agents used in thrombolytic therapy. However, further characterization and physicochemical studies are required to evaluate the real potential of endophytic fungi as sources of industrial enzymes. Full article

(This article belongs to the Section Natural Products Chemistry)

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13 pages, 2323 KiB

Open AccessPerspective

Drug Design: Where We Are and Future Prospects

by Giuseppe Zagotto and Marco Bortoli

Molecules 2021, 26(22), 7061; https://doi.org/10.3390/molecules26227061 - 22 Nov 2021

Cited by 4 | Viewed by 3119

Abstract

Medicinal chemistry is facing new challenges in approaching precision medicine. Several powerful new tools or improvements of already used tools are now available to medicinal chemists to help in the process of drug discovery, from a hit molecule to a clinically used drug. [...] Read more.

Medicinal chemistry is facing new challenges in approaching precision medicine. Several powerful new tools or improvements of already used tools are now available to medicinal chemists to help in the process of drug discovery, from a hit molecule to a clinically used drug. Among the new tools, the possibility of considering folding intermediates or the catalytic process of a protein as a target for discovering new hits has emerged. In addition, machine learning is a new valuable approach helping medicinal chemists to discover new hits. Other abilities, ranging from the better understanding of the time evolution of biochemical processes to the comprehension of the biological meaning of the data originated from genetic analyses, are on their way to progress further in the drug discovery field toward improved patient care. In this sense, the new approaches to the delivery of drugs targeted to the central nervous system, together with the advancements in understanding the metabolic pathways for a growing number of drugs and relating them to the genetic characteristics of patients, constitute important progress in the field. Full article

(This article belongs to the Special Issue From a Molecule to a Drug: Chemical Features Enhancing Pharmacological Potential)

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Graphical abstract

22 pages, 9737 KiB

Open AccessArticle

Amidine- and Amidoxime-Substituted Heterocycles: Synthesis, Antiproliferative Evaluations and DNA Binding

by Silvija Maračić, Petra Grbčić, Suresh Shammugam, Marijana Radić Stojković, Krešimir Pavelić, Mirela Sedić, Sandra Kraljević Pavelić and Silvana Raić-Malić

Molecules 2021, 26(22), 7060; https://doi.org/10.3390/molecules26227060 - 22 Nov 2021

Cited by 3 | Viewed by 2826

Abstract

The novel 1,2,3-triazolyl-appended N- and O-heterocycles containing amidine 4–11 and amidoxime 12–22 moiety were prepared and evaluated for their antiproliferative activities in vitro. Among the series of amidine-substituted heterocycles, aromatic diamidine 5 and coumarine amidine 11 had [...] Read more.

The novel 1,2,3-triazolyl-appended N- and O-heterocycles containing amidine 4–11 and amidoxime 12–22 moiety were prepared and evaluated for their antiproliferative activities in vitro. Among the series of amidine-substituted heterocycles, aromatic diamidine 5 and coumarine amidine 11 had the most potent growth-inhibitory effect on cervical carcinoma (HeLa), hepatocellular carcinoma (HepG2) and colorectal adenocarcinoma (SW620), with IC₅₀ values in the nM range. Although compound 5 was toxic to non-tumor HFF cells, compound 11 showed certain selectivity. From the amidoxime series, quinoline amidoximes 18 and 20 showed antiproliferative effects on lung adenocarcinoma (A549), HeLa and SW620 cells emphasizing compound 20 that exhibited no cytostatic effect on normal HFF fibroblasts. Results of CD titrations and thermal melting experiments indicated that compounds 5 and 10 most likely bind inside the minor groove of AT-DNA and intercalate into AU-RNA. Compounds 6, 9 and 11 bind to AT-DNA with mixed binding mode, most probably minor groove binding accompanied with aggregate binding along the DNA backbone. Full article

(This article belongs to the Special Issue Ligand Binding to DNA and RNA)

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15 pages, 4225 KiB

Open AccessArticle

A Dynamic Model and Parameter Identification of High Viscosity Magnetorheological Fluid-Based Energy Absorber with Radial Flow Mode

by Benyuan Fu, Xianming Zhang, Zhuqiang Li, Ruizhi Shu and Changrong Liao

Molecules 2021, 26(22), 7059; https://doi.org/10.3390/molecules26227059 - 22 Nov 2021

Cited by 1 | Viewed by 1618

Abstract

The excellent suspension stability of the high-viscosity linear polysiloxane magnetorheological fluid (HVLP MRF) makes it a great controlled medium for magnetorheological energy absorbers (MREAs). In our previous work, the Herschel–Bulkley flow model (HB model) was used to describe the shear-thinning rheological behavior and [...] Read more.

The excellent suspension stability of the high-viscosity linear polysiloxane magnetorheological fluid (HVLP MRF) makes it a great controlled medium for magnetorheological energy absorbers (MREAs). In our previous work, the Herschel–Bulkley flow model (HB model) was used to describe the shear-thinning rheological behavior and establish the dynamic model of an HVLP MRF-based MREA with radial flow mode. However, as the established model was implicit, the MREA response time increased and the buffer effect was degraded. To improve the time response characteristics, an explicit dynamic model based on the HB model incorporating minor losses (called the E-HBM model) is proposed in this study. The model parameters were identified based on the HBM model. To verify the E-HBM model, five evaluation parameters for the energy absorption performance of the MREA, that is, peak force, mean force, crush force efficiency, specific energy absorption, and stroke efficiency, were introduced to compare the theoretical results with the experimental results obtained using a high-speed drop tower facility with a mass of 600 kg. Then, the relative error of the crush force efficiency, specific energy absorption, and stroke efficiency was quantitatively and comprehensively analyzed considering the E-HBM model and experimental results. The results indicate that the proposed E-HBM model agrees with the impact behavior of the radial flow mode MREA. Full article

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24 pages, 1081 KiB

Open AccessArticle

Influence of Freeze-Dried Phenolic-Rich Plant Powders on the Bioactive Compounds Profile, Antioxidant Activity and Aroma of Different Types of Chocolates

by Dorota Żyżelewicz, Joanna Oracz, Martyna Bilicka, Kamila Kulbat-Warycha and Elżbieta Klewicka

Molecules 2021, 26(22), 7058; https://doi.org/10.3390/molecules26227058 - 22 Nov 2021

Cited by 10 | Viewed by 2380

Abstract

In this study, the blueberries (BLUB), raspberries (RASB), blackberries (BLCB), pomegranates pomace (POME) and beetroots (BEET) freeze-dried powders were used as the sources of phenolic compounds to enrich different types of chocolates, substituting a part of the sweetener. It was found that 1% [...] Read more.

In this study, the blueberries (BLUB), raspberries (RASB), blackberries (BLCB), pomegranates pomace (POME) and beetroots (BEET) freeze-dried powders were used as the sources of phenolic compounds to enrich different types of chocolates, substituting a part of the sweetener. It was found that 1% addition of fruit or vegetable powders to chocolates increased the content of total phenolic compounds (flavan-3-ols, phenolic acids and anthocyanins) of enriched dark and milk chocolates compared to the control ones dependent on the powder used. Among the enriched chocolates, the chocolates with the addition of BLUB powder were characterized by the highest total polyphenol content. The highest percentage increase (approximately 80%) in the total polyphenol content was observed in MCH chocolate enriched with BLUB powder. Chocolates incorporated with BLUB, RASB, BLCB and POME powders presented a richer phenolic compound profile than control counterparts. The highest DPPH radical-scavenging capacity was exhibited by the DCH98S chocolate enriched with BEET powder. However, the DCH98ESt chocolates enriched with POME and BEET powders demonstrated the highest FRAP values. An electronic nose analysis confirmed the existence of differences between the profiles of volatile compounds of various types of chocolates enriched with fruit or vegetable powders. Thus, the enrichment of dark and milk chocolates with BLUB, RASB, BLCB, POME and BEET powders seemed to be an interesting approach to enhance bioactivity and to enrich the sensory features of various chocolate types. Full article

(This article belongs to the Special Issue Food Processing and Its Impact on Phenolic and other Bioactive Constituents in Food)

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Graphical abstract

19 pages, 8470 KiB

Open AccessArticle

Evaluation of the Anticancer Potential of Crude, Irradiated Cerastes cerastes Snake Venom and Propolis Ethanolic Extract & Related Biological Alterations

by Mostafa I. Abdelglil, Sanaa O. Abdallah, Mohamed A. El-Desouky, Mohammad Y. Alfaifi, Serag Eldin I. Elbehairi and Aly F. Mohamed

Molecules 2021, 26(22), 7057; https://doi.org/10.3390/molecules26227057 - 22 Nov 2021

Cited by 4 | Viewed by 2009

Abstract

We aimed to evaluate the anticancer potential of crude venom (CV), γ irradiated Certastes cerastes venom (IRRV), and propolis ethanolic extract (PEE). IRRV showed a higher toxicity than CV, while CV-PEE showed higher toxicity than IRRV and CV against lung [A549] and prostate [...] Read more.

We aimed to evaluate the anticancer potential of crude venom (CV), γ irradiated Certastes cerastes venom (IRRV), and propolis ethanolic extract (PEE). IRRV showed a higher toxicity than CV, while CV-PEE showed higher toxicity than IRRV and CV against lung [A549] and prostate [PC3] cancer cells. Toxicity to [A549] and [PC3] cells was concentration and cell type dependent. In comparison to controls, apoptotic genes showed a significant upregulation of P53 and Casp-3 and a downregulation of Bcl-2. Also, induced elevated DNA accumulation in the [S] phase post PC3 cell treatment with IRRV and CV, as well as a significant DNA accumulation at G2/M phase after IRRV treatment of A549 cells. In contrast, PC3 cells showed a negligible cellular DNA accumulation after PEE treatment. Glutathione reductase [GR] was reduced in case of PC3 and A549 cell treated with IRRV, CV, and PEE compared with its values in untreated cell control. The Malondialdehyde [MDA] values in both cells recorded a significant elevation post IRRV treatment compared to the rest of the treatment regimen and untreated cell control. Similarly, IRRV and CV-PEE mix showed obviously higher reactive oxygen species [ROS] values than PC3 and A549 cell treatments with CV and PEE. Full article

(This article belongs to the Special Issue Natural Products from Medicinal Plants)

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12 pages, 1794 KiB

Open AccessArticle

Isoorientin Inhibits Amyloid β_25–35-Induced Neuronal Inflammation in BV2 Cells by Blocking the NF-κB Signaling Pathway

by Buyun Kim, Ki Yong Lee and Byoungduck Park

Molecules 2021, 26(22), 7056; https://doi.org/10.3390/molecules26227056 - 22 Nov 2021

Cited by 10 | Viewed by 2692

Abstract

Alzheimer’s disease (AD) is a severe neurodegenerative disorder. AD is pathologically characterized by the formation of intracellular neurofibrillary tangles, and extracellular amyloid plaques which were comprised of amyloid-beta (Aβ) peptides. Aβ induces neurodegeneration by activating microglia, which triggers neurotoxicity by releasing various inflammatory [...] Read more.

Alzheimer’s disease (AD) is a severe neurodegenerative disorder. AD is pathologically characterized by the formation of intracellular neurofibrillary tangles, and extracellular amyloid plaques which were comprised of amyloid-beta (Aβ) peptides. Aβ induces neurodegeneration by activating microglia, which triggers neurotoxicity by releasing various inflammatory mediators and reactive oxygen species (ROS). Nuclear factor-kappa B (NF-κB) is expressed in human tissues including the brain and plays an important role in Aβ-mediated neuronal inflammation. Thus, the identification of molecules that inhibit the NF-κB pathway is considered an attractive strategy for the treatment and prevention of AD. Isoorientin (3′,4′,5,7-Tetrahydroxy-6-C-glucopyranosyl flavone; ISO), which can be extracted from several plant species, such as Philostachys and Patrinia is known to have various pharmacological activities such as anticancer, antioxidant, and antibacterial activity. However, the effect of ISO on Aβ-mediated inflammation and apoptosis in the brain has yet to be elucidated. In the present study, we investigated whether ISO regulated Aβ-induced neuroinflammation in microglial cells and further explored the underlying mechanisms. Our results showed that ISO inhibited the expression of iNOS and COX-2 induced by Aβ_25–35. And, it inhibited the secretion of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). In addition, ISO reduced the ROS production in Aβ_25–35-induced BV2 cells and inhibited NF-κB activation. Furthermore, ISO blocked Aβ_25–35-induced apoptosis of BV2 cells. Based on these findings, we suggest that ISO represents a promising therapeutic drug candidate for the treatment and prevention of AD. Full article

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13 pages, 573 KiB

Open AccessReview

Applications of Lactic Acid Bacteria and Their Bacteriocins against Food Spoilage Microorganisms and Foodborne Pathogens

by Mduduzi P. Mokoena, Cornelius A. Omatola and Ademola O. Olaniran

Molecules 2021, 26(22), 7055; https://doi.org/10.3390/molecules26227055 - 22 Nov 2021

Cited by 33 | Viewed by 6497

Abstract

Lactic acid bacteria (LAB) are Gram-positive and catalase-negative microorganisms used to produce fermented foods. They appear morphologically as cocci or rods and they do not form spores. LAB used in food fermentation are from the Lactobacillus and Bifidobacterium genera and are useful in [...] Read more.

Lactic acid bacteria (LAB) are Gram-positive and catalase-negative microorganisms used to produce fermented foods. They appear morphologically as cocci or rods and they do not form spores. LAB used in food fermentation are from the Lactobacillus and Bifidobacterium genera and are useful in controlling spoilage and pathogenic microbes, due to the bacteriocins and acids that they produce. Consequently, LAB and their bacteriocins have emerged as viable alternatives to chemical food preservatives, curtesy of their qualified presumption of safety (QPS) status. There is growing interest regarding updated literature on the applications of LAB and their products in food safety, inhibition of the proliferation of food spoilage microbes and foodborne pathogens, and the mitigation of viral infections associated with food, as well as in the development of creative food packaging materials. Therefore, this review explores empirical studies, documenting applications and the extent to which LAB isolates and their bacteriocins have been used in the food industry against food spoilage microorganisms and foodborne pathogens including viruses; as well as to highlight the prospects of their numerous novel applications as components of hurdle technology to provide safe and quality food products. Full article

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14 pages, 4381 KiB

Open AccessArticle

Photocatalytic Reduction of Cr (VI) over g-C₃N₄ Photocatalysts Synthesized by Different Precursors

by Juan Liang, Chengjun Jing, Jiarong Wang and Yupawang Men

Molecules 2021, 26(22), 7054; https://doi.org/10.3390/molecules26227054 - 22 Nov 2021

Cited by 9 | Viewed by 2185

Abstract

Graphitic carbon nitride (g-C₃N₄) photocatalysts were synthesized via a one-step pyrolysis process using melamine, dicyandiamide, thiourea, and urea as precursors. The obtained g-C₃N₄ materials exhibited a significantly different performance for the photocatalytic reduction of Cr(VI) under [...] Read more.

Graphitic carbon nitride (g-C₃N₄) photocatalysts were synthesized via a one-step pyrolysis process using melamine, dicyandiamide, thiourea, and urea as precursors. The obtained g-C₃N₄ materials exhibited a significantly different performance for the photocatalytic reduction of Cr(VI) under white light irradiation, which is attributed to the altered structure and occupancies surface groups. The urea-derived g-C₃N₄ with nanosheet morphology, large specific surface area, and high occupancies of surface amine groups exhibited superior photocatalytic activity. The nanosheet morphology and large surface area facilitated the separation and transmission of charge, while the high occupancies of surface amine groups promoted the formation of hydrogen adsorption atomic centers which were beneficial to Cr(VI) reduction. Moreover, the possible reduction pathway of Cr(VI) to Cr(III) over the urea-derived g-C₃N₄ was proposed and the reduction process was mainly initiated by a direct reduction of photogenerated electrons. Full article

(This article belongs to the Special Issue Nano Environmental Materials)

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20 pages, 961 KiB

Open AccessReview

Peptide Regulation of Gene Expression: A Systematic Review

by Vladimir Khatskelevich Khavinson, Irina Grigor’evna Popovich, Natalia Sergeevna Linkova, Ekaterina Sergeevna Mironova and Anastasiia Romanovna Ilina

Molecules 2021, 26(22), 7053; https://doi.org/10.3390/molecules26227053 - 22 Nov 2021

Cited by 14 | Viewed by 4148

Abstract

Peptides are characterized by their wide range of biological activity: they regulate functions of the endocrine, nervous, and immune systems. The mechanism of such action of peptides involves their ability to regulate gene expression and protein synthesis in plants, microorganisms, insects, birds, rodents, [...] Read more.

Peptides are characterized by their wide range of biological activity: they regulate functions of the endocrine, nervous, and immune systems. The mechanism of such action of peptides involves their ability to regulate gene expression and protein synthesis in plants, microorganisms, insects, birds, rodents, primates, and humans. Short peptides, consisting of 2–7 amino acid residues, can penetrate into the nuclei and nucleoli of cells and interact with the nucleosome, the histone proteins, and both single- and double-stranded DNA. DNA–peptide interactions, including sequence recognition in gene promoters, are important for template-directed synthetic reactions, replication, transcription, and reparation. Peptides can regulate the status of DNA methylation, which is an epigenetic mechanism for the activation or repression of genes in both the normal condition, as well as in cases of pathology and senescence. In this context, one can assume that short peptides were evolutionarily among the first signaling molecules that regulated the reactions of template-directed syntheses. This situation enhances the prospects of developing effective and safe immunoregulatory, neuroprotective, antimicrobial, antiviral, and other drugs based on short peptides. Full article

(This article belongs to the Special Issue Bioactive Peptides and Proteins)

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12 pages, 4605 KiB

Open AccessArticle

Solubility of Cinnarizine in (Transcutol + Water) Mixtures: Determination, Hansen Solubility Parameters, Correlation, and Thermodynamics

by Faiyaz Shakeel, Mohsin Kazi, Fars K. Alanazi and Prawez Alam

Molecules 2021, 26(22), 7052; https://doi.org/10.3390/molecules26227052 - 22 Nov 2021

Cited by 6 | Viewed by 1772

Abstract

Between 293.2 and 313.2 K and at 0.1 MPa, the solubility of the weak base, cinnarizine (CNZ) (3), in various {Transcutol-P (TP) (1) + water (2)} combinations is reported. The Hansen solubility parameters (HSP) of CNZ and various {(TP) (1) + water (2)} [...] Read more.

Between 293.2 and 313.2 K and at 0.1 MPa, the solubility of the weak base, cinnarizine (CNZ) (3), in various {Transcutol-P (TP) (1) + water (2)} combinations is reported. The Hansen solubility parameters (HSP) of CNZ and various {(TP) (1) + water (2)} mixtures free of CNZ were also predicted using HSPiP software. Five distinct cosolvency-based mathematical models were used to link the experimentally determined solubility data of CNZ. The solubility of CNZ in mole fraction was increased with elevated temperature and TP mass fraction in {(TP) (1) + water (2)} combinations. The maximum solubility of CNZ in mole fraction was achieved in neat TP (5.83 × 10⁻² at 313.2 K) followed by the minimum in neat water (3.91 × 10⁻⁸ at 293.2 K). The values of mean percent deviation (MPD) were estimated as 2.27%, 5.15%, 27.76%, 1.24% and 1.52% for the “Apelblat, van’t Hoff, Yalkowsky–Roseman, Jouyban–Acree, and Jouyban–Acree–van’t Hoff models”, respectively, indicating good correlations. The HSP value of CNZ was closed with that of neat TP, suggesting the maximum solubilization of CNZ in TP compared with neat water and other aqueous mixtures of TP and water. The outcomes of the apparent thermodynamic analysis revealed that CNZ dissolution was endothermic and entropy-driven in all of the {(TP) (1) + water (2)} systems investigated. For {(TP) (1) + water (2)} mixtures, the enthalpy-driven mechanism was determined to be the driven mechanism for CNZ solvation. TP has great potential for solubilizing the weak base, CNZ, in water, as demonstrated by these results. Full article

(This article belongs to the Section Physical Chemistry)

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33 pages, 18376 KiB

Open AccessReview

Recent Advances in C-F Bond Cleavage Enabled by Visible Light Photoredox Catalysis

by Lei Zhou

Molecules 2021, 26(22), 7051; https://doi.org/10.3390/molecules26227051 - 22 Nov 2021

Cited by 38 | Viewed by 5836

Abstract

The creation of new bonds via C-F bond cleavage of readily available per- or oligofluorinated compounds has received growing interest. Using such a strategy, a myriad of valuable partially fluorinated products can be prepared, which otherwise are difficult to make by the conventional [...] Read more.

The creation of new bonds via C-F bond cleavage of readily available per- or oligofluorinated compounds has received growing interest. Using such a strategy, a myriad of valuable partially fluorinated products can be prepared, which otherwise are difficult to make by the conventional C-F bond formation methods. Visible light photoredox catalysis has been proven as an important and powerful tool for defluorinative reactions due to its mild, easy to handle, and environmentally benign characteristics. Compared to the classical C-F activation that proceeds via two-electron processes, radicals are the key intermediates using visible light photoredox catalysis, providing new modes for the cleavage of C-F bonds. In this review, a summary of the visible light-promoted C-F bond cleavage since 2018 was presented. The contents were classified by the fluorosubstrates, including polyfluorinated arenes, gem-difluoroalkenes, trifluoromethyl arenes, and trifluoromethyl alkenes. An emphasis is placed on the discussion of the mechanisms and limitations of these reactions. Finally, my personal perspective on the future development of this rapidly emerging field was provided. Full article

(This article belongs to the Special Issue Photoredox Catalysis for Sustainable Chemical Synthesis/Medicinal Chemistry)

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13 pages, 1975 KiB

Open AccessArticle

Synthesis and Characterization of the Ethylene-Carbonate-Linked L-Valine Derivatives of 4,4-Dimethylcurcumin with Potential Anticancer Activities

by Der-Yen Lee, Hui-Yi Lin, Manickavasakam Ramasamy, Sheng-Chu Kuo, Pei-Chih Lee and Min-Tsang Hsieh

Molecules 2021, 26(22), 7050; https://doi.org/10.3390/molecules26227050 - 22 Nov 2021

Cited by 5 | Viewed by 1966

Abstract

Natural phenolic products from herbal medicines and dietary plants constitute the main source of lead compounds for the development of the new drug. 4,4-Dimethylcurcumin (DMCU) is a synthetic curcumin derivative and exhibits anticancer activities against breast, colon, lung, and liver cancers. [...] Read more.

Natural phenolic products from herbal medicines and dietary plants constitute the main source of lead compounds for the development of the new drug. 4,4-Dimethylcurcumin (DMCU) is a synthetic curcumin derivative and exhibits anticancer activities against breast, colon, lung, and liver cancers. However, further development of DMCU is limited by unfavorable compound properties such as very low aqueous solubility and moderate stability. To increase its solubility, we installed either or both of the ethylene-carbonate-linked L-valine side chains to DMCU phenolic groups and produced targeted 1-trifluoroacetic acid (1-TFA) and 2-trifluoroacetic acid (2-TFA) derivatives. The terminus L-valine of ethylene-carbonate-linked side chain is known to be a L-type amino acid transporter 1 (LAT1) recognition element and therefore, these two derivatives were expected to readily enter into LAT1-expressing cancer cells. In practice, 1-TFA or 2-TFA were synthesized from DMCU in four steps with 34–48% overall yield. Based on the corresponding LC-MS analysis, water solubility of DMCU, 1-TFA, and 2-TFA at room temperature (25 ± 1 °C) were 0.018, 249.7, and 375.8 mg/mL, respectively, indicating >10,000-fold higher solubility of 1-TFA and 2-TFA than DMCU. Importantly, anti-proliferative assay demonstrated that 2-TFA is a potent anti-cancer agent against LAT1-expressing lung cancer cells NCI-H460, NCI-H358, and A549 cells due to its high intracellular uptake compared to DMCU and 1-TFA. In this study, we logically designed and synthesized the targeted compounds, established the LC-MS analytical methods for evaluations of drug solubility and intracellular uptake levels, and showed improved solubility and anti-cancer activities of 2-TFA. Our results provide a strategical direction for the future development of curcuminoid-like phenolic compounds. Full article

(This article belongs to the Section Medicinal Chemistry)

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16 pages, 2584 KiB

Open AccessArticle

Combining Cryo-EM Density Map and Residue Contact for Protein Secondary Structure Topologies

by Maytha Alshammari and Jing He

Molecules 2021, 26(22), 7049; https://doi.org/10.3390/molecules26227049 - 22 Nov 2021

Viewed by 2076

Abstract

Although atomic structures have been determined directly from cryo-EM density maps with high resolutions, current structure determination methods for medium resolution (5 to 10 Å) cryo-EM maps are limited by the availability of structure templates. Secondary structure traces are lines detected from a [...] Read more.

Although atomic structures have been determined directly from cryo-EM density maps with high resolutions, current structure determination methods for medium resolution (5 to 10 Å) cryo-EM maps are limited by the availability of structure templates. Secondary structure traces are lines detected from a cryo-EM density map for α-helices and β-strands of a protein. A topology of secondary structures defines the mapping between a set of sequence segments and a set of traces of secondary structures in three-dimensional space. In order to enhance accuracy in ranking secondary structure topologies, we explored a method that combines three sources of information: a set of sequence segments in 1D, a set of amino acid contact pairs in 2D, and a set of traces in 3D at the secondary structure level. A test of fourteen cases shows that the accuracy of predicted secondary structures is critical for deriving topologies. The use of significant long-range contact pairs is most effective at enriching the rank of the maximum-match topology for proteins with a large number of secondary structures, if the secondary structure prediction is fairly accurate. It was observed that the enrichment depends on the quality of initial topology candidates in this approach. We provide detailed analysis in various cases to show the potential and challenge when combining three sources of information. Full article

(This article belongs to the Special Issue Selected Papers from Computational Structural Bioinformatics Workshop 2020 (CSBW-2020))

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13 pages, 3815 KiB

Open AccessArticle

Solvothermal Synthesis of a Novel Calcium Metal-Organic Framework: High Temperature and Electrochemical Behaviour

by Russell M. Main, David B. Cordes, Aamod V. Desai, Alexandra M. Z. Slawin, Paul Wheatley, A. Robert Armstrong and Russell E. Morris

Molecules 2021, 26(22), 7048; https://doi.org/10.3390/molecules26227048 - 22 Nov 2021

Cited by 7 | Viewed by 2696

Abstract

The rapid growth in the field of metal-organic frameworks (MOFs) over recent years has highlighted their high potential in a variety of applications. For biological and environmental applications MOFs with low toxicity are vitally important to avoid any harmful effects. For this reason, [...] Read more.

The rapid growth in the field of metal-organic frameworks (MOFs) over recent years has highlighted their high potential in a variety of applications. For biological and environmental applications MOFs with low toxicity are vitally important to avoid any harmful effects. For this reason, Ca-based MOFs are highly desirable owing to their low cost and high biocompatibility. Useful Ca MOFs are still rare owing to the ionic character and large size of the Ca²⁺ ion tending to produce dense phases. Presented here is a novel Ca-based MOF containing 2,3-dihyrdoxyterephthalate (2,3-dhtp) linkers Ca(2,3-dhtp)(H₂O) (SIMOF-4). The material undergoes a phase transformation on heating, which can be followed by variable temperature powder X-ray diffraction. The structure of the high temperature form was obtained using single-crystal X-ray diffraction. The electrochemical properties of SIMOF-4 were also investigated for use in a Na ion battery. Full article

(This article belongs to the Special Issue Advances in Chemical Crystallography: A Themed Issue Honoring Professor Alexandra M. Z. Slawin on the Occasion of Her 60th Birthday)

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15 pages, 7288 KiB

Open AccessArticle

Theoretical Thermodynamic Efficiency Limit of Isothermal Solar Fuel Generation from H₂O/CO₂ Splitting in Membrane Reactors

by Hongsheng Wang, Hui Kong, Jian Wang, Mingkai Liu, Bosheng Su and Sean-Thomas B. Lundin

Molecules 2021, 26(22), 7047; https://doi.org/10.3390/molecules26227047 - 22 Nov 2021

Cited by 4 | Viewed by 1831

Abstract

Solar fuel generation from thermochemical H₂O or CO₂ splitting is a promising and attractive approach for harvesting fuel without CO₂ emissions. Yet, low conversion and high reaction temperature restrict its application. One method of increasing conversion at a lower [...] Read more.

Solar fuel generation from thermochemical H₂O or CO₂ splitting is a promising and attractive approach for harvesting fuel without CO₂ emissions. Yet, low conversion and high reaction temperature restrict its application. One method of increasing conversion at a lower temperature is to implement oxygen permeable membranes (OPM) into a membrane reactor configuration. This allows for the selective separation of generated oxygen and causes a forward shift in the equilibrium of H₂O or CO₂ splitting reactions. In this research, solar-driven fuel production via H₂O or CO₂ splitting with an OPM reactor is modeled in isothermal operation, with an emphasis on the calculation of the theoretical thermodynamic efficiency of the system. In addition to the energy required for the high temperature of the reaction, the energy required for maintaining low oxygen permeate pressure for oxygen removal has a large influence on the overall thermodynamic efficiency. The theoretical first-law thermodynamic efficiency is calculated using separation exergy, an electrochemical O₂ pump, and a vacuum pump, which shows a maximum efficiency of 63.8%, 61.7%, and 8.00% for H₂O splitting, respectively, and 63.6%, 61.5%, and 16.7% for CO₂ splitting, respectively, in a temperature range of 800 °C to 2000 °C. The theoretical second-law thermodynamic efficiency is 55.7% and 65.7% for both H₂O splitting and CO₂ splitting at 2000 °C. An efficient O₂ separation method is extremely crucial to achieve high thermodynamic efficiency, especially in the separation efficiency range of 0–20% and in relatively low reaction temperatures. This research is also applicable in other isothermal H₂O or CO₂ splitting systems (e.g., chemical cycling) due to similar thermodynamics. Full article

(This article belongs to the Special Issue Functional Molecules for Electrochemical Energy Conversion and Storage)

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16 pages, 2235 KiB

Open AccessArticle

Adsorption Capacities of Iron Hydroxide for Arsenate and Arsenite Removal from Water by Chemical Coagulation: Kinetics, Thermodynamics and Equilibrium Studies

by Muhammad Ali Inam, Rizwan Khan, Kang Hoon Lee, Muhammad Akram, Zameer Ahmed, Ki Gang Lee and Young Min Wie

Molecules 2021, 26(22), 7046; https://doi.org/10.3390/molecules26227046 - 22 Nov 2021

Cited by 8 | Viewed by 1879

Abstract

Arsenic (As)-laden wastewater may pose a threat to biodiversity when released into soil and water bodies without treatment. The current study investigated the sorption properties of both As(III, V) oxyanions onto iron hydroxide (FHO) by chemical coagulation. The potential mechanisms were identified using [...] Read more.

Arsenic (As)-laden wastewater may pose a threat to biodiversity when released into soil and water bodies without treatment. The current study investigated the sorption properties of both As(III, V) oxyanions onto iron hydroxide (FHO) by chemical coagulation. The potential mechanisms were identified using the adsorption models, ζ-potential, X-ray diffraction (XRD) and Fourier Transform Infrared Spectrometry (FT-IR) analysis. The results indicate that the sorption kinetics of pentavalent and trivalent As species closely followed the pseudo-second-order model, and the adsorption rates of both toxicants were remarkably governed by pH as well as the quantity of FHO in suspension. Notably, the FHO formation was directly related to the amount of ferric chloride (FC) coagulant added in the solution. The sorption isotherm results show a better maximum sorption capacity for pentavalent As ions than trivalent species, with the same amount of FHO in the suspensions. The thermodynamic study suggests that the sorption process was spontaneously exothermic with increased randomness. The ζ-potential, FT-IR and XRD analyses confirm that a strong Fe-O bond with As(V) and the closeness of the surface potential of the bonded complex to the point of zero charge (pH_zpc) resulted in the higher adsorption affinity of pentavalent As species than trivalent ions in most aquatic conditions. Moreover, the presence of sulfates, phosphates, and humic and salicylic acid significantly affected the As(III, V) sorption performance by altering the surface properties of Fe precipitates. The combined effect of charge neutralization, complexation, oxidation and multilayer chemisorption was identified as a major removal mechanism. These findings may provide some understanding regarding the fate, transport and adsorption properties onto FHO of As oxyanions in a complex water environment. Full article

(This article belongs to the Special Issue Nano Environmental Materials)

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22 pages, 3782 KiB

Open AccessArticle

Adaptive Modelling of Mutated FMO3 Enzyme Could Unveil Unexplored Scenarios Linking Variant Haplotypes to TMAU Phenotypes

by Simona Alibrandi, Fabiana Nicita, Luigi Donato, Concetta Scimone, Carmela Rinaldi, Rosalia D’Angelo and Antonina Sidoti

Molecules 2021, 26(22), 7045; https://doi.org/10.3390/molecules26227045 - 22 Nov 2021

Cited by 2 | Viewed by 2055

Abstract

Background: Trimethylaminuria (TMAU) is a rare genetic disease characterized by the accumulation of trimethylamine (TMA) and its subsequent excretion trough main body fluids, determining the characteristic fish odour in affected patients. We realized an experimental study to investigate the role of several coding [...] Read more.

Background: Trimethylaminuria (TMAU) is a rare genetic disease characterized by the accumulation of trimethylamine (TMA) and its subsequent excretion trough main body fluids, determining the characteristic fish odour in affected patients. We realized an experimental study to investigate the role of several coding variants in the causative gene FMO3, that were only considered as polymorphic or benign, even if the available literature on them did not functionally explain their ineffectiveness on the encoded enzyme. Methods: Mutational analysis of 26 TMAU patients was realized by Sanger sequencing. Detected variants were, subsequently, deeply statistically and in silico characterized to determine their possible effects on the enzyme activity. To achieve this goal, a docking prediction for TMA/FMO3 and an unbinding pathway study were performed. Finally, a TMAO/TMA urine quantification by 1H-NMR spectroscopy was performed to support modelling results. Results: The FMO3 screening of all patients highlighted the presence of 17 variants distributed in 26 different haplotypes. Both non-sense and missense considered variants might impair the enzymatic kinetics of FMO3, probably reducing the interaction time between the protein catalytic site and TMA, or losing the wild-type binding site. Conclusions: Even if further functional assays will confirm our predictive results, considering the possible role of FMO3 variants with still uncertain effects, might be a relevant step towards the detection of novel scenarios in TMAU etiopathogenesis. Full article

(This article belongs to the Special Issue Molecular Modeling: Advancements and Applications)

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16 pages, 4856 KiB

Open AccessReview

State of the Art in Crystallization of LiNbO₃ and Their Applications

by Kunfeng Chen, Yunzhong Zhu, Zhihua Liu and Dongfeng Xue

Molecules 2021, 26(22), 7044; https://doi.org/10.3390/molecules26227044 - 22 Nov 2021

Cited by 26 | Viewed by 3930

Abstract

Lithium niobate (LiNbO₃) crystals are important dielectric and ferroelectric materials, which are widely used in acoustics, optic, and optoelectrical devices. The physical and chemical properties of LiNbO₃ are dependent on microstructures, defects, compositions, and dimensions. In this review, we first [...] Read more.

Lithium niobate (LiNbO₃) crystals are important dielectric and ferroelectric materials, which are widely used in acoustics, optic, and optoelectrical devices. The physical and chemical properties of LiNbO₃ are dependent on microstructures, defects, compositions, and dimensions. In this review, we first discussed the crystal and defect structures of LiNbO₃, then the crystallization of LiNbO₃ single crystal, and the measuring methods of Li content were introduced to reveal reason of growing congruent LiNbO₃ and variable Li/Nb ratios. Afterwards, this review provides a summary about traditional and non-traditional applications of LiNbO₃ crystals. The development of rare earth doped LiNbO₃ used in illumination, and fluorescence temperature sensing was reviewed. In addition to radio-frequency applications, surface acoustic wave devices applied in high temperature sensor and solid-state physics were discussed. Thanks to its properties of spontaneous ferroelectric polarization, and high chemical stability, LiNbO₃ crystals showed enhanced performances in photoelectric detection, electrocatalysis, and battery. Furthermore, domain engineering, memristors, sensors, and harvesters with the use of LiNbO₃ crystals were formulated. The review is concluded with an outlook of challenges and potential payoff for finding novel LiNbO₃ applications. Full article

(This article belongs to the Section Nanochemistry)

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27 pages, 2755 KiB

Open AccessFeature PaperReview

Polymeric Scaffolds for Dental, Oral, and Craniofacial Regenerative Medicine

by David T. Wu, Jose G. Munguia-Lopez, Ye Won Cho, Xiaolu Ma, Vivian Song, Zhiyue Zhu and Simon D. Tran

Molecules 2021, 26(22), 7043; https://doi.org/10.3390/molecules26227043 - 22 Nov 2021

Cited by 50 | Viewed by 6907

Abstract

Dental, oral, and craniofacial (DOC) regenerative medicine aims to repair or regenerate DOC tissues including teeth, dental pulp, periodontal tissues, salivary gland, temporomandibular joint (TMJ), hard (bone, cartilage), and soft (muscle, nerve, skin) tissues of the craniofacial complex. Polymeric materials have a broad [...] Read more.

Dental, oral, and craniofacial (DOC) regenerative medicine aims to repair or regenerate DOC tissues including teeth, dental pulp, periodontal tissues, salivary gland, temporomandibular joint (TMJ), hard (bone, cartilage), and soft (muscle, nerve, skin) tissues of the craniofacial complex. Polymeric materials have a broad range of applications in biomedical engineering and regenerative medicine functioning as tissue engineering scaffolds, carriers for cell-based therapies, and biomedical devices for delivery of drugs and biologics. The focus of this review is to discuss the properties and clinical indications of polymeric scaffold materials and extracellular matrix technologies for DOC regenerative medicine. More specifically, this review outlines the key properties, advantages and drawbacks of natural polymers including alginate, cellulose, chitosan, silk, collagen, gelatin, fibrin, laminin, decellularized extracellular matrix, and hyaluronic acid, as well as synthetic polymers including polylactic acid (PLA), polyglycolic acid (PGA), polycaprolactone (PCL), poly (ethylene glycol) (PEG), and Zwitterionic polymers. This review highlights key clinical applications of polymeric scaffolding materials to repair and/or regenerate various DOC tissues. Particularly, polymeric materials used in clinical procedures are discussed including alveolar ridge preservation, vertical and horizontal ridge augmentation, maxillary sinus augmentation, TMJ reconstruction, periodontal regeneration, periodontal/peri-implant plastic surgery, regenerative endodontics. In addition, polymeric scaffolds application in whole tooth and salivary gland regeneration are discussed. Full article

(This article belongs to the Special Issue Polymer Scaffolds for Biomedical Applications 2021)

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12 pages, 1591 KiB

Open AccessArticle

The Influence of 5′,8-Cyclo-2′-deoxypurines on the Mitochondrial Repair of Clustered DNA Damage in Xrs5 Cells: The Preliminary Study

by Karolina Boguszewska, Julia Kaźmierczak-Barańska and Bolesław T. Karwowski

Molecules 2021, 26(22), 7042; https://doi.org/10.3390/molecules26227042 - 22 Nov 2021

Cited by 3 | Viewed by 1406

Abstract

The 5′,8-cyclo-2′-deoxypurines (cdPus) affect the DNA structure. When these bulky structures are a part of clustered DNA lesions (CDL), they affect the repair of the other lesions within the cluster. Mitochondria are crucial for cell survival and have their own genome, hence, are [...] Read more.

The 5′,8-cyclo-2′-deoxypurines (cdPus) affect the DNA structure. When these bulky structures are a part of clustered DNA lesions (CDL), they affect the repair of the other lesions within the cluster. Mitochondria are crucial for cell survival and have their own genome, hence, are highly interesting in the context of CDL repair. However, no studies are exploring this topic. Here, the initial stages of mitochondrial base excision repair (mtBER) were considered—the strand incision and elongation. The repair of a single lesion (apurinic site (AP site)) accompanying the cdPu within the double-stranded CDL has been investigated for the first time. The type of cdPu, its diastereomeric form, and the interlesion distance were taken into consideration. For these studies, the established experimental model of short oligonucleotides (containing AP sites located ≤7 base pairs to the cdPu in both directions) and mitochondrial extracts of the xrs5 cells were used. The obtained results have shown that the presence of cdPus influenced the processing of an AP site within the CDL. Levels of strand incision and elongation were higher for oligos containing RcdA and ScdG than for those with ScdA and RcdG. Investigated stages of mtBER were more efficient for DNA containing AP sites located on 5′-end side of cdPu than on its 3′-end side. In conclusion, the presence of cdPus in mtDNA structure may affect mtBER (processing the second mutagenic lesion within the CDL). As impaired repair processes may lead to serious biological consequences, further studies concerning the mitochondrial repair of CDL are highly demanded. Full article

(This article belongs to the Special Issue The Beauty of Clustered DNA Lesion)

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15 pages, 4721 KiB

Open AccessArticle

Microstructural Evolution and High-Performance Giant Dielectric Properties of Lu³⁺/Nb⁵⁺ Co-Doped TiO₂ Ceramics

by Noppakorn Thanamoon, Narong Chanlek, Pornjuk Srepusharawoot, Ekaphan Swatsitang and Prasit Thongbai

Molecules 2021, 26(22), 7041; https://doi.org/10.3390/molecules26227041 - 22 Nov 2021

Cited by 1 | Viewed by 1577

Abstract

Giant dielectric (GD) oxides exhibiting extremely large dielectric permittivities (ε’ > 10⁴) have been extensively studied because of their potential for use in passive electronic devices. However, the unacceptable loss tangents (tanδ) and temperature instability with respect to ε’ continue to [...] Read more.

Giant dielectric (GD) oxides exhibiting extremely large dielectric permittivities (ε’ > 10⁴) have been extensively studied because of their potential for use in passive electronic devices. However, the unacceptable loss tangents (tanδ) and temperature instability with respect to ε’ continue to be a significant hindrance to their development. In this study, a novel GD oxide, exhibiting an extremely large ε’ value of approximately 7.55 × 10⁴ and an extremely low tanδ value of approximately 0.007 at 10³ Hz, has been reported. These remarkable properties were attributed to the synthesis of a Lu³⁺/Nb⁵⁺ co-doped TiO₂ (LuNTO) ceramic containing an appropriate co-dopant concentration. Furthermore, the variation in the ε’ values between the temperatures of −60 °C and 210 °C did not exceed ±15% of the reference value obtained at 25 °C. The effects of the grains, grain boundaries, and second phase particles on the dielectric properties were evaluated to determine the dielectric properties exhibited by LuNTO ceramics. A highly dense microstructure was obtained in the as-sintered ceramics. The existence of a LuNbTiO₆ microwave-dielectric phase was confirmed when the co-dopant concentration was increased to 1%, thereby affecting the dielectric behavior of the LuNTO ceramics. The excellent dielectric properties exhibited by the LuNTO ceramics were attributed to their inhomogeneous microstructure. The microstructure was composed of semiconducting grains, consisting of Ti³⁺ ions formed by Nb⁵⁺ dopant ions, alongside ultra-high-resistance grain boundaries. The effects of the semiconducting grains, insulating grain boundaries (GBs), and secondary microwave phase particles on the dielectric relaxations are explained based on their interfacial polarizations. The results suggest that a significant enhancement of the GB properties is the key toward improvement of the GD properties, while the presence of second phase particles may not always be effective. Full article

(This article belongs to the Section Materials Chemistry)

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17 pages, 5946 KiB

Open AccessArticle

LINC02532 Contributes to Radiosensitivity in Clear Cell Renal Cell Carcinoma through the miR-654-5p/YY1 Axis

by Xiaoguang Zhou, Bowen Zeng, Yansheng Li, Haozhou Wang and Xiaodong Zhang

Molecules 2021, 26(22), 7040; https://doi.org/10.3390/molecules26227040 - 22 Nov 2021

Cited by 7 | Viewed by 1903

Abstract

Background: Studies have shown that long non-coding RNAs (lncRNAs) play essential roles in tumor progression and can affect the response to radiotherapy, including in clear cell renal cell carcinoma (ccRCC). LINC02532 has been found to be upregulated in ccRCC. However, not much is [...] Read more.

Background: Studies have shown that long non-coding RNAs (lncRNAs) play essential roles in tumor progression and can affect the response to radiotherapy, including in clear cell renal cell carcinoma (ccRCC). LINC02532 has been found to be upregulated in ccRCC. However, not much is known about this lncRNA. Hence, this study aimed to investigate the role of LINC02532 in ccRCC, especially in terms of radioresistance. Methods: Quantitative real-time PCR was used to detect the expression of LINC02532, miR-654-5p, and YY1 in ccRCC cells. Protein levels of YY1, cleaved PARP, and cleaved-Caspase-3 were detected by Western blotting. Cell survival fractions, viability, and apoptosis were determined by clonogenic survival assays, CCK-8 assays, and flow cytometry, respectively. The interplay among LINC02532, miR-654-5p, and YY1 was detected by chromatin immunoprecipitation and dual-luciferase reporter assays. In addition, in vivo xenograft models were established to investigate the effect of LINC02532 on ccRCC radioresistance in 10 nude mice. Results: LINC02532 was highly expressed in ccRCC cells and was upregulated in the cells after irradiation. Moreover, LINC02532 knockdown enhanced cell radiosensitivity both in vitro and in vivo. Furthermore, YY1 activated LINC02532 in ccRCC cells, and LINC02532 acted as a competing endogenous RNA that sponged miR-654-5p to regulate YY1 expression. Rescue experiments indicated that miR-654-5p overexpression or YY1 inhibition recovered ccRCC cell functions that had been previously impaired by LINC02532 overexpression. Conclusions: Our results revealed a positive feedback loop of LINC02532/miR-654-5p/YY1 in regulating the radiosensitivity of ccRCC, suggesting that LINC02532 might be a potential target for ccRCC radiotherapy. This study could serve as a foundation for further research on the role of LINC02532 in ccRCC and other cancers. Full article

(This article belongs to the Special Issue Theranostic Applications of Functional Nucleic Acids)

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12 pages, 3692 KiB

Open AccessArticle

Inverse Vulcanization of a Natural Monoene with Sulfur as Sustainable Electrochemically Active Materials for Lithium-Sulfur Batteries

by Jian Xiao, Zhicong Liu, Wangnian Zhang, Ning Deng, Jijun Liu and Fulai Zhao

Molecules 2021, 26(22), 7039; https://doi.org/10.3390/molecules26227039 - 22 Nov 2021

Cited by 11 | Viewed by 2592

Abstract

A novel soluble copolymer poly(S-MVT) was synthesized using a relatively quick one-pot solvent-free method, inverse vulcanization. Both of the two raw materials are sustainable, i.e., elemental sulfur is a by-product of the petroleum industry and 4-Methyl-5-vinylthiazole (MVT) is a natural monoene compound. The [...] Read more.

A novel soluble copolymer poly(S-MVT) was synthesized using a relatively quick one-pot solvent-free method, inverse vulcanization. Both of the two raw materials are sustainable, i.e., elemental sulfur is a by-product of the petroleum industry and 4-Methyl-5-vinylthiazole (MVT) is a natural monoene compound. The microstructure of poly(S-MVT) was characterized by FT-IR, ¹H NMR, XPS spectroscopy, XRD, DSC SEM, and TEM. Test results indicated that the copolymers possess protonated thiazole nitrogen atoms, meso/macroporous structure, and solubility in tetrahydrofuran and chloroform. Moreover, the improved electronic properties of poly(S-MVT) relative to elemental sulfur have also been investigated by density functional theory (DFT) calculations. The copolymers are utilized successfully as the cathode active material in Li-S batteries. Upon employment, the copolymer with 15% MVT content provided good cycling stability at a capacity of ∼514 mA h g⁻¹ (based on the mass of copolymer) and high Coulombic efficiencies (∼100%) over 100 cycles, as well as great rate performance. Full article

(This article belongs to the Topic Nanomaterials for Sustainable Energy Applications)

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16 pages, 1346 KiB

Open AccessArticle

Antimicrobial Properties of Lyophilized Extracts of Olive Fruit, Pomegranate and Orange Peel Extracts against Foodborne Pathogenic and Spoilage Bacteria and Fungi In Vitro and in Food Matrices

by Chrysanthi Mitsagga, Konstantinos Petrotos and Ioannis Giavasis

Molecules 2021, 26(22), 7038; https://doi.org/10.3390/molecules26227038 - 21 Nov 2021

Cited by 6 | Viewed by 2587

Abstract

Several novel antimicrobials with different concentrations of olive, pomegranate, and orange fruit pulp extracts were produced from agricultural byproducts and, after lyophilization, their antimicrobial activity and potential synergistic effects were evaluated in vitro and in food samples against foodborne pathogenic and spoilage bacteria [...] Read more.

Several novel antimicrobials with different concentrations of olive, pomegranate, and orange fruit pulp extracts were produced from agricultural byproducts and, after lyophilization, their antimicrobial activity and potential synergistic effects were evaluated in vitro and in food samples against foodborne pathogenic and spoilage bacteria and fungi. The Minimum Inhibitory of the tested bacteria was 7.5% or 10%, while fungi were inhibited at a concentration of 10% or above. The optical density of bacterial and yeast cultures was reduced to a different extent with all tested antimicrobial powders, compared to a control without antimicrobials, and mycelium growth of fungi was also restricted with extracts containing at least 90% olive extract. In food samples with inoculated pathogens and spoilage bacteria and fungi, the 100% olive extract was most inhibitory against E. coli, S. typhimurium, and L. monocytogenes in fresh burger and cheese spread samples (by 0.6 to 1.8 log cfu/g), except that S. typhimurium was better inhibited by a 90% olive and 10% pomegranate extract in burgers. The latter extract was also the most effective in controlling the growth of inoculated fungi (Aspergillus niger, Penicillium italicum, Rhodotorula mucilaginosa) in both yogurt and tomato juice samples, where it reduced fungal growth by 1–2.2 log cfu/g at the end of storage period. The results demonstrate that these novel encapsulated extracts could serve as natural antimicrobials of wide spectrum, in order to replace synthetic preservatives in foods and cosmetics. Full article

(This article belongs to the Special Issue Advanced Production, Analysis and Applications of Natural Antimicrobials and Antioxidants)

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22 pages, 9296 KiB

Open AccessArticle

The Antileukemic Effect of Xestoquinone, A Marine-Derived Polycyclic Quinone-Type Metabolite, Is Mediated through ROS-Induced Inhibition of HSP-90

by Kuan-Chih Wang, Mei-Chin Lu, Kai-Cheng Hsu, Mohamed El-Shazly, Shou-Ping Shih, Ssu-Ting Lien, Fu-Wen Kuo, Shyh-Chyun Yang, Chun-Lin Chen and Yu-Chen S. H. Yang

Molecules 2021, 26(22), 7037; https://doi.org/10.3390/molecules26227037 - 21 Nov 2021

Cited by 6 | Viewed by 2009

Abstract

Xestoquinone is a polycyclic quinone-type metabolite with a reported antitumor effect. We tested the cytotoxic activity of xestoquinone on a series of hematological cancer cell lines. The antileukemic effect of xestoquinone was evaluated in vitro and in vivo. This marine metabolite suppressed the [...] Read more.

Xestoquinone is a polycyclic quinone-type metabolite with a reported antitumor effect. We tested the cytotoxic activity of xestoquinone on a series of hematological cancer cell lines. The antileukemic effect of xestoquinone was evaluated in vitro and in vivo. This marine metabolite suppressed the proliferation of Molt-4, K562, and Sup-T1 cells with IC₅₀ values of 2.95 ± 0.21, 6.22 ± 0.21, and 8.58 ± 0.60 µM, respectively, as demonstrated by MTT assay. In the cell-free system, it inhibited the activity of topoisomerase I (Topo I) and II (Topo II) by 50% after treatment with 0.235 and 0.094 μM, respectively. The flow cytometric analysis indicated that the cytotoxic effect of xestoquinone was mediated through the induction of multiple apoptotic pathways in Molt-4 cells. The pretreatment of Molt-4 cells with N-acetyl cysteine (NAC) diminished the disruption of the mitochondrial membrane potential (MMP) and apoptosis, as well as retaining the expression of both Topo I and II. In the nude mice xenograft model, the administration of xestoquinone (1 μg/g) significantly attenuated tumor growth by 31.2% compared with the solvent control. Molecular docking, Western blotting, and thermal shift assay verified the catalytic inhibitory activity of xestoquinone by high binding affinity to HSP-90 and Topo I/II. Our findings indicated that xestoquinone targeted leukemia cancer cells through multiple pathways, suggesting its potential application as an antileukemic drug lead. Full article

(This article belongs to the Special Issue Mechanism of Anticancer Activity of Marine Natural Compounds)

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16 pages, 1105 KiB

Open AccessReview

Andrographolide: A Herbal-Chemosynthetic Approach for Enhancing Immunity, Combating Viral Infections, and Its Implication on Human Health

by Archana Mishra, Haq Abdul Shaik, Rakesh Kumar Sinha and Bakht Ramin Shah

Molecules 2021, 26(22), 7036; https://doi.org/10.3390/molecules26227036 - 21 Nov 2021

Cited by 13 | Viewed by 4584

Abstract

Plants consistently synthesize and accumulate medically valuable secondary metabolites which can be isolated and clinically tested under in vitro conditions. An advancement with such important phytochemical production has been recognized and utilized as herbal drugs. Bioactive andrographolide (AGL; C₂₀H₃₀O [...] Read more.

Plants consistently synthesize and accumulate medically valuable secondary metabolites which can be isolated and clinically tested under in vitro conditions. An advancement with such important phytochemical production has been recognized and utilized as herbal drugs. Bioactive andrographolide (AGL; C₂₀H₃₀O₅) isolated from Andrographis paniculate (AP) (Kalmegh) is a diterpenoid lactones having multifunctional medicinal properties including anti-manic, anti-inflammatory, liver, and lung protective. AGL is known for its immunostimulant activity against a variety of microbial infections thereby, regulating classical and alternative macrophage activation, Ag-specific antibody production during immune disorder therapy. In vitro studies with AGL found it to be effective against multiple tumors, neuronal disorders, diabetes, pneumonia, fibrosis, and other diverse therapeutic misadventures. Generally, virus-based diseases like ZIKA, influenza A virus subtype (H1NI), Ebola (EBOV), Dengue (DENV), and coronavirus (COVID-19) epidemics have greatly increased scientific interest and demands to develop more effective and economical immunomodulating drugs with minimal side effects. Trials and in vitro pharmacological studies with AGL and medicinally beneficial herbs might contribute to benefit the human population without using chemical-based synthetic drugs. In this review, we have discussed the possible role of AGL as a promising herbal-chemo remedy during human diseases, viral infections and as an immunity booster. Full article

(This article belongs to the Special Issue Natural Products: From Isolation and Identification to Biological Activity—Second Edition)

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13 pages, 1136 KiB

Open AccessReview

Being Uncertain in Chromatographic Calibration—Some Unobvious Details in Experimental Design

by Łukasz Komsta, Katarzyna Wicha-Komsta and Tomasz Kocki

Molecules 2021, 26(22), 7035; https://doi.org/10.3390/molecules26227035 - 21 Nov 2021

Viewed by 1361

Abstract

This is an introductory tutorial and review about the uncertainty problem in chromatographic calibration. It emphasizes some unobvious, but important details influencing errors in the calibration curve estimation, uncertainty in prediction, as well as the connections and dependences between them, all from various [...] Read more.

This is an introductory tutorial and review about the uncertainty problem in chromatographic calibration. It emphasizes some unobvious, but important details influencing errors in the calibration curve estimation, uncertainty in prediction, as well as the connections and dependences between them, all from various perspectives of uncertainty measurement. Nonuniform D-optimal designs coming from Fedorov theorem are computed and presented. As an example, all possible designs of 24 calibration samples (3–8, 4–6, 6–4, 8–3 and 12–2, both uniform and D-optimal) are compared in context of many optimality criteria. It can be concluded that there are only two independent (orthogonal, but slightly complex) trends in optimality of these designs. The conclusions are important, as the uniform designs with many concentrations are not the best choices, contrary to some intuitive perception. Nonuniform designs are visibly better alternative in most calibration cases. Full article

(This article belongs to the Special Issue Chromatography and Chemometrics 2021)

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8 pages, 1658 KiB

Open AccessArticle

Three New Phthalide Glycosides from the Rhizomes of Cnidium officinale and Their Recovery Effect on Damaged Otic Hair Cells in Zebrafish

by Hyoung-Geun Kim, Seon Min Oh, Na Woo Kim, Ji Heon Shim, Youn Hee Nam, Trong Nguyen Nguyen, Min-Ho Lee, Dae Young Lee, Tong Ho Kang and Nam-In Baek

Molecules 2021, 26(22), 7034; https://doi.org/10.3390/molecules26227034 - 21 Nov 2021

Cited by 8 | Viewed by 1658

Abstract

The extract from Cnidium officinale rhizomes was shown in a prior experiment to markedly recover otic hair cells in zebrafish damaged by neomycin. The current study was brought about to identify the principal metabolite. Column chromatography using octadecyl SiO₂ and SiO₂ [...] Read more.

The extract from Cnidium officinale rhizomes was shown in a prior experiment to markedly recover otic hair cells in zebrafish damaged by neomycin. The current study was brought about to identify the principal metabolite. Column chromatography using octadecyl SiO₂ and SiO₂ was performed to isolate the major metabolites from the active fraction. The chemical structures were resolved on the basis of spectroscopic data, including NMR, IR, MS, and circular dichroism (CD) data. The isolated phthalide glycosides were assessed for their recovery effect on damaged otic hair cells in neomycin-treated zebrafish. Three new phthalide glycosides were isolated, and their chemical structures, including stereochemical characteristics, were determined. Two glycosides (0.1 μM) showed a recovery effect (p < 0.01) on otic hair cells in zebrafish affected by neomycin ototoxicity. Repeated column chromatography led to the isolation of three new phthalide glycosides, named ligusticosides C (1), D (2), and E (3). Ligusticoside C and ligusticoside E recovered damaged otic hair cells in zebrafish. Full article

(This article belongs to the Special Issue Biological Activities of Traditional Medicinal Plants)

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16 pages, 849 KiB

Open AccessArticle

Ancient Wheat and Quinoa Flours as Ingredients for Pasta Dough—Evaluation of Thermal and Rheological Properties

by Dorota Gałkowska, Teresa Witczak and Mariusz Witczak

Molecules 2021, 26(22), 7033; https://doi.org/10.3390/molecules26227033 - 21 Nov 2021

Cited by 6 | Viewed by 1846

Abstract

The aim of this study was to investigate thermal and rheological properties of selected ancient grain flours and to evaluate rheological properties of mixtures thereof represented by pasta dough and dry pasta. Flours from spelt, einkorn, and emmer ancient wheat varieties were combined [...] Read more.

The aim of this study was to investigate thermal and rheological properties of selected ancient grain flours and to evaluate rheological properties of mixtures thereof represented by pasta dough and dry pasta. Flours from spelt, einkorn, and emmer ancient wheat varieties were combined with quinoa flour. All these flour sources are considered healthy grains of high bioactive component content. Research results were compared to durum wheat flour or spelt wheat flour systems. Differential scanning calorimeter (DSC) and a rapid visco analyzer (RVA) were used to investigate the phase transition behavior of the flours and pasting characteristics of the flours and dried pasta. Angular frequency sweep experiments and creep and recovery tests of the pasta dough were performed. The main components modifying the pasta dough structure were starch and water. Moreover, the proportion of the individual flours influenced the rheological properties of the dough. The durum wheat dough was characterized by the lowest values of the K′ and K″ parameters of the power law models (24,861 Pa·sⁿ′ and 10,687 Pa·sⁿ″, respectively) and the highest values of the instantaneous (J₀) and retardation (J₁) compliances (0.453 × 10⁻⁴ Pa and 0.644 × 10⁻⁴ Pa, respectively). Replacing the spelt wheat flour with the other ancient wheat flours and quinoa flour increased the proportion of elastic properties and decreased values of the J₀ and J₁ of the pasta dough. Presence of the quinoa flour increased pasting temperature (from 81.4 up to 83.3 °C) and significantly influenced pasting viscosities of the spelt wheat pasta samples. This study indicates a potential for using mixtures of spelt, einkorn, and emmer wheat flours with quinoa flour in the production of innovative pasta dough and pasta products. Full article

(This article belongs to the Special Issue Physicochemical Properties of Food - 2nd Edition)

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Molecules, Volume 26, Issue 22 (November-2 2021) – 307 articles

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