Molecules

26 pages, 2915 KiB

Open AccessArticle

Exploring New Structural Features of the 18β-Glycyrrhetinic Acid Scaffold for the Inhibition of Anaplastic Lymphoma Kinase

by Dong Cai, ZhiHua Zhang, Yu Chen, YanYan Zhang, YuQi Sun and YiXia Gong

Molecules 2019, 24(19), 3631; https://doi.org/10.3390/molecules24193631 - 08 Oct 2019

Cited by 9 | Viewed by 2641

Abstract

Novel 18β-glycyrrhetinic acid derivatives possessing a carbamate moiety and structurally similar ester derivatives were developed and evaluated for their efficacy as antitumor inhibitors. In the cellular assays, most of the N-substituted carbamate derivatives at the C3-position exhibited potent activities. The results of [...] Read more.

Novel 18β-glycyrrhetinic acid derivatives possessing a carbamate moiety and structurally similar ester derivatives were developed and evaluated for their efficacy as antitumor inhibitors. In the cellular assays, most of the N-substituted carbamate derivatives at the C3-position exhibited potent activities. The results of SAR investigation revealed that the introduction of the morpholine group at the C30-COOH led to a significant loss of the inhibitory potency. Among the ester derivatives, the ester group at C3-position also determined a noticeable reduction in the efficacy. Compound 3j exhibited the most prominent antiproliferative activity against six human cancer cells (A549, HT29, HepG2, MCF-7, PC-3, and Karpas299). Furthermore, compound 3j exerted a moderate inhibiting effect on the ALK. The results of molecular docking analyses suggested that it could bind well to the active site of the receptor ALK, which was consistent with the biological data. These results might inspire further structural optimization of 18β-glycyrrhetinic acid aiming at the development of potent antitumor agents. The structures 4d, 4g, 4h, 4j, and 4n were studied by X-ray crystallographic analyses. Full article

(This article belongs to the Section Medicinal Chemistry)

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16 pages, 4006 KiB

Open AccessArticle

UHPLC-HR-MS/MS-Guided Recovery of Bioactive Flavonol Compounds from Greco di Tufo Vine Leaves

by Simona Piccolella, Giuseppina Crescente, Maria Grazia Volpe, Marina Paolucci and Severina Pacifico

Molecules 2019, 24(19), 3630; https://doi.org/10.3390/molecules24193630 - 08 Oct 2019

Cited by 18 | Viewed by 3210

Abstract

Leaves of Vitis vinifera cv. Greco di Tufo, a precious waste made in the Campania Region (Italy), after vintage harvest, underwent reduction, lyophilization, and ultrasound-assisted maceration in ethanol. The alcoholic extract, as evidenced by a preliminary UHPLC-HR-MS analysis, showed a high metabolic complexity. [...] Read more.

Leaves of Vitis vinifera cv. Greco di Tufo, a precious waste made in the Campania Region (Italy), after vintage harvest, underwent reduction, lyophilization, and ultrasound-assisted maceration in ethanol. The alcoholic extract, as evidenced by a preliminary UHPLC-HR-MS analysis, showed a high metabolic complexity. Thus, the extract was fractionated, obtaining, among others, a fraction enriched in flavonol glycosides and glycuronides. Myricetin, quercetin, kaempferol, and isorhamnetin derivatives were tentatively identified based on their relative retention time and TOF-MS² data. As the localization of saccharidic moiety in glycuronide compounds proved to be difficult due to the lack of well-established fragmentation pattern and/or the absence of characteristic key fragments, to obtain useful MS information and to eliminate matrix effect redundancies, the isolation of the most abundant extract’s compound was achieved. HR-MS/MS spectra of the compound, quercetin-3-O-glucuronide, allowed us to thoroughly rationalize its fragmentation pattern, and to unravel the main differences between MS/MS behavior of flavonol glycosides and glycuronides. Furthermore, cytotoxicity assessment on the (poly)phenol rich fraction and the pure isolated compound was carried out using central nervous system cell lines. The chemoprotective effect of both the (poly)phenol fraction and quercetin-3-O-glucuronide was evaluated. Full article

(This article belongs to the Special Issue Food Bioactives: Chemical Challenges and Bio-Opportunities)

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13 pages, 1591 KiB

Open AccessArticle

Level of Biogenic Amines in Red and White Wines, Dietary Exposure, and Histamine-Mediated Symptoms upon Wine Ingestion

by Francesco Esposito, Paolo Montuori, Mario Schettino, Salvatore Velotto, Tommaso Stasi, Raffaele Romano and Teresa Cirillo

Molecules 2019, 24(19), 3629; https://doi.org/10.3390/molecules24193629 - 08 Oct 2019

Cited by 28 | Viewed by 4767

Abstract

Biogenic amines (BAs) are involved in physiological processes. Foods where typically high levels of BAs occur are fermented food and beverage. This work set out to evaluate the occurrence of BAs in red and white wines, and to also ascertain the dietary exposure [...] Read more.

Biogenic amines (BAs) are involved in physiological processes. Foods where typically high levels of BAs occur are fermented food and beverage. This work set out to evaluate the occurrence of BAs in red and white wines, and to also ascertain the dietary exposure to BAs among consumers. Besides, a case report of a probable histamine intoxication upon ingestion of contaminated wine was described. The samples were analyzed through derivatization with dansyl chloride and HPLC-UV detection. Red wines showed higher levels of BAs, especially putrescine (PUT) and histamine (HIS), than white wines (median concentrations of 7.30 and 2.45 mg/L, respectively). However, results of our investigation showed that the dietary exposure to BAs through the consumption of wine (red and white) were lower than the recommended maximum levels for the acute exposure to HIS and tyramine (TYR). In contrast, the levels of BAs in wine on tap were much higher than in bottled wine and close to recommended values. The levels of HIS, TYR, and PUT in tap wine of 9.97, 8.23, and 13.01 mg/L, respectively, were associated with histamine-mediated symptoms in six young individuals after consumption of about three glasses of wine. The overall results and multivariate analysis confirm that red wine shows a higher concentration of BAs than white wine, especially putrescine and histamine. This finding is attributable to the malolactic fermentation that is common for most red wine production. It is also evident that incorrect preservation processes can lead to an increase in BA levels, probably due to the action of bacteria with high decarboxylase activity. The exposure values, although below the toxicity thresholds, could lead to histamine-mediated symptoms in susceptible individuals, also according to the case report discussed in this study. Full article

(This article belongs to the Special Issue Current Issues in Food Microbiology, Safety and Fermentation)

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7 pages, 807 KiB

Open AccessArticle

Two New AChE Inhibitors Isolated from Li Folk Herb Heilaohu “Kadsura coccinea” Stems

by Sheng Zhuo Huang, Lin Ping Duan, Hao Wang, Wen Li Mei and Hao Fu Dai

Molecules 2019, 24(19), 3628; https://doi.org/10.3390/molecules24193628 - 08 Oct 2019

Cited by 8 | Viewed by 2332

Abstract

Two new triterpenoids, named kadsuricoccins A and B, together with three known ones, were isolated from the Li folk herb Heilaohu, the stems of Kadsura coccinea (Lem.) A. C. Smith, which was used for food and as a healthy supplement. Their structures were [...] Read more.

Two new triterpenoids, named kadsuricoccins A and B, together with three known ones, were isolated from the Li folk herb Heilaohu, the stems of Kadsura coccinea (Lem.) A. C. Smith, which was used for food and as a healthy supplement. Their structures were elucidated by comprehensive analyses of mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopic data. To search healthy components, an acetylcholinesterase (AChE) inhibitory activity test by Ellman’s Method was conducted, kadsuricoccins A and B showed activity with the AChE inhibit index (AII) up to 68.96% ± 0.19% and 57.8% ± 0.11% at 94 nM (compared with positive control tacrine AII 79.80% ± 0.20%, 9.4 nM), respectively. Full article

(This article belongs to the Section Natural Products Chemistry)

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13 pages, 1049 KiB

Open AccessArticle

Peptidomic Approach for the Identification of Peptides with Potential Antioxidant and Anti-Hyperthensive Effects Derived From Asparagus By-Products

by Carmela Maria Montone, Riccardo Zenezini Chiozzi, Nicola Marchetti, Andrea Cerrato, Michela Antonelli, Anna Laura Capriotti, Chiara Cavaliere, Susy Piovesana and Aldo Laganà

Molecules 2019, 24(19), 3627; https://doi.org/10.3390/molecules24193627 - 08 Oct 2019

Cited by 25 | Viewed by 3892

Abstract

Asparagus waste represents products of great interest since many compounds with high biological value are located in the lower portion of the spears. The extraction of bioactive compounds from asparagus by-products is therefore crucial for the purpose of adding value to these by-products. [...] Read more.

Asparagus waste represents products of great interest since many compounds with high biological value are located in the lower portion of the spears. The extraction of bioactive compounds from asparagus by-products is therefore crucial for the purpose of adding value to these by-products. In this paper, bioactive peptides from asparagus waste were extracted, digested, purified and identified. In particular, Alcalase^® was chosen as the enzyme to use to obtain protein hydrolysate due to its low cost and, consequently, the possibility of implementing the method on a large scale. In order to simplify the peptide extract to reach better identification, the hydrolysate was fractionated by reversed-phase chromatography in 10 fractions. Two tests were carried out for antioxidant activity (ABTS-DPPH) and one for antihypertensive activity (ACE). Fractions with a higher bioactivity score were identified by peptidomics technologies and screened for bioactivity with the use of bioinformatics. For ACE-inhibitor activity, two peptides were synthetized, PDWFLLL and ASQSIWLPGWL, which provided an EC₅₀ value of 1.76 µmol L⁻¹ and 4.02 µmol L⁻¹, respectively. For the antioxidant activity, by DPPH assay, MLLFPM exhibited the lowest EC50 value at 4.14 µmol L⁻¹, followed by FIARNFLLGW and FAPVPFDF with EC50 values of 6.76 µmol L⁻¹ and 10.01 µmol L⁻¹, respectively. A validation of the five identified peptides was also carried out. The obtained results showed that peptides obtained from asparagus by-products are of interest for their biological activity and are suitable for being used as functional ingredients. Full article

(This article belongs to the Collection Advances in Liquid Separation Techniques for Food and Pharmaceutical Analysis)

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20 pages, 1306 KiB

Open AccessFeature PaperReview

Red Wine Consumption and Cardiovascular Health

by Luigi Castaldo, Alfonso Narváez, Luana Izzo, Giulia Graziani, Anna Gaspari, Giovanni Di Minno and Alberto Ritieni

Molecules 2019, 24(19), 3626; https://doi.org/10.3390/molecules24193626 - 08 Oct 2019

Cited by 141 | Viewed by 26517

Abstract

Wine is a popular alcoholic beverage that has been consumed for hundreds of years. Benefits from moderate alcohol consumption have been widely supported by the scientific literature and, in this line, red wine intake has been related to a lesser risk for coronary [...] Read more.

Wine is a popular alcoholic beverage that has been consumed for hundreds of years. Benefits from moderate alcohol consumption have been widely supported by the scientific literature and, in this line, red wine intake has been related to a lesser risk for coronary heart disease (CHD). Experimental studies and meta-analyses have mainly attributed this outcome to the presence in red wine of a great variety of polyphenolic compounds such as resveratrol, catechin, epicatechin, quercetin, and anthocyanin. Resveratrol is considered the most effective wine compound with respect to the prevention of CHD because of its antioxidant properties. The mechanisms responsible for its putative cardioprotective effects would include changes in lipid profiles, reduction of insulin resistance, and decrease in oxidative stress of low-density lipoprotein cholesterol (LDL-C). The aim of this review is to summarize the accumulated evidence correlating moderate red wine consumption with prevention of CHD by focusing on the different mechanisms underlying this relationship. Furthermore, the chemistry of wine as well as chemical factors that influence the composition of the bioactive components of red wine are also discussed. Full article

(This article belongs to the Special Issue The Antioxidant Capacities of Natural Products 2019)

14 pages, 1637 KiB

Open AccessArticle

Bimodular Antiparallel G-Quadruplex Nanoconstruct with Antiproliferative Activity

by Olga Antipova, Nadezhda Samoylenkova, Ekaterina Savchenko, Elena Zavyalova, Alexander Revishchin, Galina Pavlova and Alexey Kopylov

Molecules 2019, 24(19), 3625; https://doi.org/10.3390/molecules24193625 - 08 Oct 2019

Cited by 9 | Viewed by 2740

Abstract

Oligonucleotides with an antiproliferative activity for human cancer cells have attracted attention over the past decades; many of them have a G-quadruplex structure (GQ), and a cryptic target. In particular, DNA oligonucleotide HD1, a minimal GQ, could inhibit proliferation of some cancer cell [...] Read more.

Oligonucleotides with an antiproliferative activity for human cancer cells have attracted attention over the past decades; many of them have a G-quadruplex structure (GQ), and a cryptic target. In particular, DNA oligonucleotide HD1, a minimal GQ, could inhibit proliferation of some cancer cell lines. The HD1 is a 15-nucleotide DNA oligonucleotide that folds into a minimal chair-like monomolecular antiparallel GQ structure. In this study, for eight human cancer cell lines, we have analyzed the antiproliferative activities of minimal bimodular DNA oligonucleotide, biHD1, which has two HD1 modules covalently linked via single T-nucleotide residue. Oligonucleotide biHD1 exhibits a dose-dependent antiproliferative activity for lung cancer cell line RL-67 and cell line of central nervous system cancer U87 by MTT-test and Ki-67 immunoassay. The study of derivatives of biHD1 for the RL-67 and U87 cell lines revealed a structure-activity correlation of GQ folding and antiproliferative activity. Therefore, a covalent joining of two putative GQ modules within biHD1 molecule provides the antiproliferative activity of initial HD1, opening a possibility to design further GQ multimodular nanoconstructs with antiproliferative activity—either as themselves or as carriers. Full article

(This article belongs to the Special Issue Aptamers: Successes, Limitations and Future Directions)

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17 pages, 3931 KiB

Open AccessArticle

Schizandrin Protects against OGD/R-Induced Neuronal Injury by Suppressing Autophagy: Involvement of the AMPK/mTOR Pathway

by Guangyun Wang, Tiezheng Wang, Yuanyuan Zhang, Fang Li, Boyang Yu and Junping Kou

Molecules 2019, 24(19), 3624; https://doi.org/10.3390/molecules24193624 - 08 Oct 2019

Cited by 53 | Viewed by 4629

Abstract

The neuroprotective role of schizandrin (SA) in cerebral ischemia-reperfusion (I/R) was recently highlighted. However, whether SA plays a regulatory role on autophagy in cerebral I/R injury is still unclear. This study aimed to explore whether the neuroprotective mechanisms of SA were linked to [...] Read more.

The neuroprotective role of schizandrin (SA) in cerebral ischemia-reperfusion (I/R) was recently highlighted. However, whether SA plays a regulatory role on autophagy in cerebral I/R injury is still unclear. This study aimed to explore whether the neuroprotective mechanisms of SA were linked to its regulation of AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/autophagy pathway in vivo and in vitro. The present study confirmed that SA significantly improved oxygen-glucose deprivation/re-oxygenation (OGD/R)-induced PC12 cells injury. The results of immunoblotting and confocal microscope showed that SA decreased autophagy in OGD/R-injured PC12 cells, which was reflected by the decreased Beclin-1 and LC3-II expression, autophagy flux level, and LC3 puncta formation. In addition, the autophagy inducer rapamycin partially prevented the effects of SA on cell viability and autophagy after OGD/R, whereas the autophagy inhibitor 3-methyladenine (3-MA) exerted the opposite effect. The results of Western blotting showed that SA markedly decreased the phosphorylation of AMPK (p-AMPK), whereas the phosphor-mTOR (p-mTOR) levels increased in the presence of OGD/R insult. Furthermore, pretreatment with the AMPK inducer AICAR partially reversed the protective effects and autophagy inhibition of SA. However, AMPK inhibitor Compound C pretreatment further promoted the inhibition of SA on autophagy induction and cell damage induced by OGD/R. Taken together, these findings demonstrate that SA protects against OGD/R insult by inhibiting autophagy through the regulation of the AMPK-mTOR pathway and that SA may have therapeutic value for protecting neurons from cerebral ischemia. Full article

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6 pages, 3455 KiB

Open AccessCommunication

Synthesis and Properties of a Bay-Annulated-Indigo Tetramer Based on Low-Cost Spiro[Fluorene-9,9′-Xanthene] Core

by Bao-Yi Ren, Yan-Mei Tan, Chang-Liang Sun and Yong-Gang Sheng

Molecules 2019, 24(19), 3623; https://doi.org/10.3390/molecules24193623 - 08 Oct 2019

Cited by 1 | Viewed by 2714

Abstract

A three-dimensional bay-annulated-indigo (BAI) tetramer has been prepared by appending BAI units onto a low-cost spiro[fluorene-9,9′-xanthene] (SFX) core. The target compound 4BAI-SFX exhibits strong and broad absorption in the visible region covering the range of 450~700 nm. The electrochemical measurement illuminates the characteristics [...] Read more.

A three-dimensional bay-annulated-indigo (BAI) tetramer has been prepared by appending BAI units onto a low-cost spiro[fluorene-9,9′-xanthene] (SFX) core. The target compound 4BAI-SFX exhibits strong and broad absorption in the visible region covering the range of 450~700 nm. The electrochemical measurement illuminates the characteristics of a deep lowest unoccupied molecular orbital (LUMO) level and multiple redox states of 4BAI-SFX. These results suggest that 4BAI-SFX should be a selectable electron-transporting material for eco-friendly organic semiconductors. Full article

(This article belongs to the Section Materials Chemistry)

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12 pages, 1800 KiB

Open AccessArticle

Interaction Effects between Doxorubicin and Hernandezine on the Pharmacokinetics by Liquid Chromatography Coupled with Mass Spectrometry

by Yang Song, Yuan Zhang, Wei-Peng Zhang, Bao-Zhen Zhang, Ke-Fei Wang and Xue-Song Feng

Molecules 2019, 24(19), 3622; https://doi.org/10.3390/molecules24193622 - 08 Oct 2019

Cited by 4 | Viewed by 2764

Abstract

Doxorubicin (DOX) is an effective anti-tumor drug widely used in clinics. Hernandezine (HER), isolated from a Chinese medicinal herb, has a selective inhibitory effect on DOX multidrug resistance, making DOX more effective in treating cancer. The aim of this study was to investigate [...] Read more.

Doxorubicin (DOX) is an effective anti-tumor drug widely used in clinics. Hernandezine (HER), isolated from a Chinese medicinal herb, has a selective inhibitory effect on DOX multidrug resistance, making DOX more effective in treating cancer. The aim of this study was to investigate the effect of the interaction of HER and DOX on pharmacokinetics. Male Sparague–Dawley rats were randomly divided into three groups: a single DOX group, a single HER group, and a combination group. Plasma concentrations of DOX and HER were determined by the LC-MS/MS method at specified time points after administration, and the main pharmacokinetic parameters were estimated. The results showed that there were significant differences in the C_max and AUC_0–∞ of DOX in the single drug group and combined drug group, indicating that HER could improve the absorption of DOX. However, DOX in combination, in turn, reduced the free drug concentration of HER, possibly because DOX enhanced the HER drug–protein binding effect. The results could be used as clinical guidance for DOX and HER to avoid adverse reactions. Full article

(This article belongs to the Special Issue Recent Trends in Pharmaceutical Analytical Chemistry)

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16 pages, 2272 KiB

Open AccessArticle

Correlation between Quality and Geographical Origins of Cortex Periplocae, Based on the Qualitative and Quantitative Determination of Chemical Markers Combined with Chemical Pattern Recognition

by Mengyuan Gao, Xiaohua Jia, Xuhua Huang, Wei Wang, Guangzhe Yao, Yanxu Chang, Huizi Ouyang, Tianxiang Li and Jun He

Molecules 2019, 24(19), 3621; https://doi.org/10.3390/molecules24193621 - 08 Oct 2019

Cited by 7 | Viewed by 2467

Abstract

Quality assessment of Cortex Periplocae remains a challenge, due to its complex chemical profile. This study aims to investigate the chemical components of Cortex Periplocae, including its non-volatile and volatile constituents, via liquid chromatograph–mass spectrometry (LC-MS/MS) and gas chromatography–mass spectrometry (GC-MS) assays. [...] Read more.

Quality assessment of Cortex Periplocae remains a challenge, due to its complex chemical profile. This study aims to investigate the chemical components of Cortex Periplocae, including its non-volatile and volatile constituents, via liquid chromatograph–mass spectrometry (LC-MS/MS) and gas chromatography–mass spectrometry (GC-MS) assays. The established strategy manifested that Cortex Periplocae from different producing areas was determined by identifying 27 chemical markers with ultra-high-performance liquid chromatography, coupled with quadrupole tandem time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS), including four main groups of cardiac glycosides, organic acids, aldehydes, and oligosaccharides. These groups’ variable importance in the projection (VIP) were greater than 1. Simultaneously, the samples were divided into four categories, combined with multivariate statistical analysis. In addition, in order to further understand the difference in the content of samples from different producing areas, nine chemical markers of Cortex Periplocae from 14 different producing areas were determined by high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS), and results indicated that the main effective constituents of Cortex Periplocae varied with places of origin. Furthermore, in GC-MS analysis, samples were divided into three groups with multivariate statistical analysis; in addition, 22 differential components whose VIP were greater than 1 were identified, which were principally volatile oils and fatty acids. Finally, the relative contents of seven main volatile constituents were obtained, which varied extremely with the producing areas. The results showed that the LC-MS/MS and GC-MS assays, combined with multivariate statistical analysis for Cortex Periplocae, provided a comprehensive and effective means for its quality evaluation. Full article

(This article belongs to the Section Analytical Chemistry)

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17 pages, 1945 KiB

Open AccessArticle

Anti-Platelet Properties of Phenolic Extracts from the Leaves and Twigs of Elaeagnus rhamnoides (L.) A. Nelson

by Bartosz Skalski, Bogdan Kontek, Agata Rolnik, Beata Olas, Anna Stochmal and Jerzy Żuchowski

Molecules 2019, 24(19), 3620; https://doi.org/10.3390/molecules24193620 - 08 Oct 2019

Cited by 10 | Viewed by 3067

Abstract

Sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) is a small tree or bush. It belongs to the Elaeagnaceae family, and has been used for many years in traditional medicine in both Europe and Asia. However, there is no data on the effect [...] Read more.

Sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) is a small tree or bush. It belongs to the Elaeagnaceae family, and has been used for many years in traditional medicine in both Europe and Asia. However, there is no data on the effect of sea buckthorn leaves and twigs on the properties of blood platelets. The aim of the study was to analyze the biological activity of phenolic extracts from leaves and twigs of sea buckthorn in blood platelets in vitro. Two sets of extracts were used: (1) phenolic compounds from twigs and (2) phenolic compounds from leaves. Their biological effects on human blood platelets were studied by blood platelet adhesion, platelet aggregation, arachidonic acid metabolism and the generation of superoxide anion. Cytotoxicity was also evaluated against platelets. The action of extracts from sea buckthorn twigs and leaves was compared to activities of the phenolic extract (a commercial product from the berries of Aronia melanocarpa (Aronox^®) with antioxidative and antiplatelet properties. This study is the first to demonstrate that extracts from sea buckthorn leaves and twigs are a source of bioactive compounds which may be used for the prophylaxis and treatment of cardiovascular pathologies associated with blood platelet hyperactivity. Both leaf and twig extracts were found to display anti-platelet activity in vitro. Moreover, the twig extract (rich in proanthocyanidins) displayed better anti-platelet potential than the leaf extract or aronia extract. Full article

(This article belongs to the Special Issue Bioactive Phenolic and Polyphenolic Compounds)

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12 pages, 2459 KiB

Open AccessFeature PaperArticle

Co-Localization of DNA i-Motif-Forming Sequences and 5-Hydroxymethyl-cytosines in Human Embryonic Stem Cells

by Yogini P. Bhavsar-Jog, Eric Van Dornshuld, Tracy A. Brooks, Gregory S. Tschumper and Randy M. Wadkins

Molecules 2019, 24(19), 3619; https://doi.org/10.3390/molecules24193619 - 08 Oct 2019

Cited by 4 | Viewed by 2618

Abstract

G-quadruplexes (G4s) and i-motifs (iMs) are tetraplex DNA structures. Sequences capable of forming G4/iMs are abundant near the transcription start sites (TSS) of several genes. G4/iMs affect gene expression in vitro. Depending on the gene, the presence of G4/iMs can enhance or suppress [...] Read more.

G-quadruplexes (G4s) and i-motifs (iMs) are tetraplex DNA structures. Sequences capable of forming G4/iMs are abundant near the transcription start sites (TSS) of several genes. G4/iMs affect gene expression in vitro. Depending on the gene, the presence of G4/iMs can enhance or suppress expression, making it challenging to discern the underlying mechanism by which they operate. Factors affecting G4/iM structures can provide additional insight into their mechanism of regulation. One such factor is epigenetic modification. The 5-hydroxymethylated cytosines (5hmCs) are epigenetic modifications that occur abundantly in human embryonic stem cells (hESC). The 5hmCs, like G4/iMs, are known to participate in gene regulation and are also enriched near the TSS. We investigated genomic co-localization to assess the possibility that these two elements may play an interdependent role in regulating genes in hESC. Our results indicate that amongst 15,760 G4/iM-forming locations, only 15% have 5hmCs associated with them. A detailed analysis of G4/iM-forming locations enriched in 5hmC indicates that most of these locations are in genes that are associated with cell differentiation, proliferation, apoptosis and embryogenesis. The library generated from our analysis is an important resource for investigators exploring the interdependence of these DNA features in regulating expression of selected genes in hESC. Full article

(This article belongs to the Special Issue Current Trends in Applications of Cytosine-rich Oligonucleotides)

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16 pages, 999 KiB

Open AccessFeature PaperArticle

Ultrasound and Microwave Assisted Extraction of Opuntia Fruit Peels Biocompounds: Optimization and Comparison Using RSM-CCD

by Bruno Melgar, Maria Inês Dias, Lillian Barros, Isabel C.F.R. Ferreira, Antonio D. Rodriguez-Lopez and Esperanza M. Garcia-Castello

Molecules 2019, 24(19), 3618; https://doi.org/10.3390/molecules24193618 - 08 Oct 2019

Cited by 39 | Viewed by 4119

Abstract

Ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) of bioactive compounds, peels from Opuntia engelmannii cultivar (cv.) Valencia were optimized by response surface methodology. Randomized extraction runs were performed for each of the technologies employed in order to build effective models with maximum (bioactive [...] Read more.

Ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) of bioactive compounds, peels from Opuntia engelmannii cultivar (cv.) Valencia were optimized by response surface methodology. Randomized extraction runs were performed for each of the technologies employed in order to build effective models with maximum (bioactive molecules content and yield) and minimum (antioxidant activity) responses. A 5-level, 4-factor central composite design was used to obtain target responses as a function of extraction time (t), solid to liquid ratio (S/L), methanol concentration (metOH), and temperature (T). Specific response optimization for each technology was analyzed, discussed, and general optimization from all the responses together was also gather. The optimum values for each factor were: t = 2.5 and 1.4 min, S/L = 5 and 5 g/L, metOH = 34.6 and 0% of methanol and T = 30 and 36.6 °C, achieving maximum responses of 201.6 and 132.9 mg of betalains/g, 13.9 and 8.0 mg of phenolic acids/g, 2.4 and 1.5 mg of flavonoids/g, 71.8% and 79.1% of extractable solid and IC₅₀ values for the antioxidant activity of 2.9 and 3.6, for UAE and MAE, respectively. The present study suggested UAE as the best extraction system, in order to maximize recovery of bioactive compounds with a high antioxidant activity. Full article

(This article belongs to the Special Issue Extraction, Purification and Application of Antioxidants from Food Matrices, Wastes and By-Products)

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12 pages, 3432 KiB

Open AccessArticle

Expanding the Reaction Space of Linkage-Specific Sialic Acid Derivatization

by Tamas Pongracz, Manfred Wuhrer and Noortje de Haan

Molecules 2019, 24(19), 3617; https://doi.org/10.3390/molecules24193617 - 08 Oct 2019

Cited by 18 | Viewed by 5170

Abstract

The human glycome is characterized by a high degree of sialylation, affecting, amongst others, cell–cell interactions and protein half-life. An established method for the linkage isomer-specific characterization of N-glycan sialylation is based on the linkage-specific derivatization of sialylated glycoconjugates, inducing ethyl esterification [...] Read more.

The human glycome is characterized by a high degree of sialylation, affecting, amongst others, cell–cell interactions and protein half-life. An established method for the linkage isomer-specific characterization of N-glycan sialylation is based on the linkage-specific derivatization of sialylated glycoconjugates, inducing ethyl esterification of α2,6-linked sialic acids and lactonization of α2,3-linked sialic acids. While the carboxylic acid activator and nucleophile used in this reaction received extensive investigation, the role of the catalyst was never thoroughly explored. A frequently used catalyst for the linkage-specific esterification of sialic acids is 1-hydroxybenzotriazole (HOBt). Here, a systematic evaluation was performed of five HOBt alternatives in combination with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) in ethanol for the linkage-specific derivatization of sialic acids. Derivatized glycans were analyzed by MALDI-TOF-MS and the catalyst performance was evaluated based on the completeness of the reactions and the linkage-specificity obtained. The use of both 6-Cl-HOBt and 6-CF₃-HOBt resulted in high linkage-specificity and minimal byproduct formation, similar to the benchmark method using HOBt. Performing the reaction with these catalysts at neutral or acidic pH showed comparable efficiencies on both sialyllactose and complex-type N-glycans. The reported investigations resulted in an expansion of the reaction space for linkage-specific sialic acid derivatization. Full article

(This article belongs to the Special Issue Oligosaccharides and Glyco-Conjugates II)

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21 pages, 5936 KiB

Open AccessReview

A Review on the Reactivity of 1-Amino-2-Nitroguanidine (ANQ)

by Jinghua Wang, Meng Cai, Fengqi Zhao and Kangzhen Xu

Molecules 2019, 24(19), 3616; https://doi.org/10.3390/molecules24193616 - 08 Oct 2019

Cited by 6 | Viewed by 3835

Abstract

1-Amino-2-nitroguanidine (ANQ) is a high-energy nitrogen-rich compound with good detonation properties and low sensitivities. ANQ has only a central carbon atom with three small groups around it, including an amino, a hydrazine and a nitroxyl group. Though the molecular structure of ANQ is [...] Read more.

1-Amino-2-nitroguanidine (ANQ) is a high-energy nitrogen-rich compound with good detonation properties and low sensitivities. ANQ has only a central carbon atom with three small groups around it, including an amino, a hydrazine and a nitroxyl group. Though the molecular structure of ANQ is very simple, its reactivity is surprisingly abundant. ANQ can undergo various reactions, including reduction reaction, acylation reaction, salification reaction, coordination reaction, aldimine condensation reaction, cyclization reaction and azide reaction. Many new energetic compounds were purposely obtained through these reactions. These reactions were systematically summarized in this review, and detonation properties of some energetic compounds were compared. In the field of energetic materials, ANQ and some derivatives exhibit good application prospects. Full article

(This article belongs to the Special Issue Advanced Chemistry of Energetic Materials)

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19 pages, 5601 KiB

Open AccessFeature PaperArticle

The Power of LC-MS Based Multiomics: Exploring Adipogenic Differentiation of Human Mesenchymal Stem/Stromal Cells

by Evelyn Rampler, Dominik Egger, Harald Schoeny, Mate Rusz, Maria Pires Pacheco, Giada Marino, Cornelia Kasper, Thomas Naegele and Gunda Koellensperger

Molecules 2019, 24(19), 3615; https://doi.org/10.3390/molecules24193615 - 08 Oct 2019

Cited by 22 | Viewed by 5832

Abstract

The molecular study of fat cell development in the human body is essential for our understanding of obesity and related diseases. Mesenchymal stem/stromal cells (MSC) are the ideal source to study fat formation as they are the progenitors of adipocytes. In this work, [...] Read more.

The molecular study of fat cell development in the human body is essential for our understanding of obesity and related diseases. Mesenchymal stem/stromal cells (MSC) are the ideal source to study fat formation as they are the progenitors of adipocytes. In this work, we used human MSCs, received from surgery waste, and differentiated them into fat adipocytes. The combination of several layers of information coming from lipidomics, metabolomics and proteomics enabled network analysis of the biochemical pathways in adipogenesis. Simultaneous analysis of metabolites, lipids, and proteins in cell culture is challenging due to the compound’s chemical difference, so most studies involve separate analysis with unimolecular strategies. In this study, we employed a multimolecular approach using a two–phase extraction to monitor the crosstalk between lipid metabolism and protein-based signaling in a single sample (~10⁵ cells). We developed an innovative analytical workflow including standardization with in-house produced ¹³C isotopically labeled compounds, hyphenated high-end mass spectrometry (high-resolution Orbitrap MS), and chromatography (HILIC, RP) for simultaneous untargeted screening and targeted quantification. Metabolite and lipid concentrations ranged over three to four orders of magnitude and were detected down to the low fmol (absolute on column) level. Biological validation and data interpretation of the multiomics workflow was performed based on proteomics network reconstruction, metabolic modelling (MetaboAnalyst 4.0), and pathway analysis (OmicsNet). Comparing MSCs and adipocytes, we observed significant regulation of different metabolites and lipids such as triglycerides, gangliosides, and carnitine with 113 fully reprogrammed pathways. The observed changes are in accordance with literature findings dealing with adipogenic differentiation of MSC. These results are a proof of principle for the power of multimolecular extraction combined with orthogonal LC-MS assays and network construction. Considering the analytical and biological validation performed in this study, we conclude that the proposed multiomics workflow is ideally suited for comprehensive follow-up studies on adipogenesis and is fit for purpose for different applications with a high potential to understand the complex pathophysiology of diseases. Full article

(This article belongs to the Special Issue Mass Spectrometry Based Lipidomics)

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15 pages, 1349 KiB

Open AccessArticle

Matrix Discriminant Analysis Evidenced Surface-Lithium as an Important Factor to Increase the Hydrolytic Saccharification of Sugarcane Bagasse

by Ana Sílvia de Almeida Scarcella, Alexandre Favarin Somera, Christiane da Costa Carreira Nunes, Eleni Gomes, Ana Claudia Vici, Marcos Silveira Buckeridge and Maria de Lourdes Teixeira de Moraes Polizeli

Molecules 2019, 24(19), 3614; https://doi.org/10.3390/molecules24193614 - 08 Oct 2019

Cited by 1 | Viewed by 2167

Abstract

Statistical evidence pointing to the very soft change in the ionic composition on the surface of the sugar cane bagasse is crucial to improve yields of sugars by hydrolytic saccharification. Removal of Li⁺ by pretreatments exposing -OH sites was the most important [...] Read more.

Statistical evidence pointing to the very soft change in the ionic composition on the surface of the sugar cane bagasse is crucial to improve yields of sugars by hydrolytic saccharification. Removal of Li⁺ by pretreatments exposing -OH sites was the most important factor related to the increase of saccharification yields using enzyme cocktails. Steam Explosion and Microwave:H₂SO₄ pretreatments produced unrelated structural changes, but similar ionic distribution patterns. Both increased the saccharification yield 1.74-fold. NaOH produced structural changes related to Steam Explosion, but released surface-bounded Li⁺ obtaining 2.04-fold more reducing sugars than the control. In turn, the higher amounts in relative concentration and periodic structures of Li⁺ on the surface observed in the control or after the pretreatment with Ethanol:DMSO:Ammonium Oxalate, blocked -OH and O⁻ available for ionic sputtering. These changes correlated to 1.90-fold decrease in saccharification yields. Li⁺ was an activator in solution, but its presence and distribution pattern on the substrate was prejudicial to the saccharification. Apparently, it acts as a phase-dependent modulator of enzyme activity. Therefore, no correlations were found between structural changes and the efficiency of the enzymatic cocktail used. However, there were correlations between the Li⁺ distribution patterns and the enzymatic activities that should to be shown. Full article

(This article belongs to the Special Issue Efficient Technology for the Pretreatment of Biomass II)

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17 pages, 2176 KiB

Open AccessArticle

Antidiabetic and Cosmeceutical Potential of Common Barbery (Berberis vulgaris L.) Root Bark Extracts Obtained by Optimization of ‘Green’ Ultrasound-Assisted Extraction

by Marina Dulić, Petar Ciganović, Lovorka Vujić and Marijana Zovko Končić

Molecules 2019, 24(19), 3613; https://doi.org/10.3390/molecules24193613 - 08 Oct 2019

Cited by 20 | Viewed by 3958

Abstract

Berberis vulgaris is rich in berberine, an isoquinoline alkaloid, with antidiabetic activity, often used topically for skin-related problems. The aim of this work was to develop a “green” method for berberine extraction using mixtures of water with glycerol, a non-toxic, environmentally-friendly solvent. Response [...] Read more.

Berberis vulgaris is rich in berberine, an isoquinoline alkaloid, with antidiabetic activity, often used topically for skin-related problems. The aim of this work was to develop a “green” method for berberine extraction using mixtures of water with glycerol, a non-toxic, environmentally-friendly solvent. Response surface methodology based on Box–Behnken design was used to optimize the experimental conditions for ultrasound-assisted extraction of berberine and anti-radical components from B. vulgaris root bark. The independent variables were temperature (X₁), glycerol concentration (X₂), and ultrasound power (X₃), while the responses were berberine concentration and DPPH radical scavenging activity of the extracts (RSA IC₅₀). The response values of the extracts prepared at optimum conditions were (response, X₁, X₂, X₃): berberine yield (145.5 μg/mL; 80 °C, 50%, 144 W) and RSA IC₅₀ (58.88 μL/mL; 80 °C, 30%, 720 W). The observed values deviated from the predicted values by −3.45% and 6.42% for berberine and RSA IC₅₀, respectively, thus indicating the validity of the selected models. The prepared extracts demonstrated antioxidant, anti-melanogenic, and anti-inflammatory activity, as well excellent α-glucosidase and α-amylase inhibitory activity. The displayed biological properties and lack of glycerol toxicity makes the prepared extracts suitable for direct inclusion into antidiabetic and dermatologic food supplements and topical products. Full article

(This article belongs to the Special Issue Sonochemistry and Green Chemistry Applications II)

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10 pages, 26079 KiB

Open AccessArticle

Applicability of a Monolithic Column for Separation of Isoquinoline Alkalodis from Chelidonium majus Extract

by Michał Staniak, Magdalena Wójciak-Kosior, Ireneusz Sowa, Maciej Strzemski, Jan Sawicki, Sławomir Dresler and Katarzyna Tyszczuk-Rotko

Molecules 2019, 24(19), 3612; https://doi.org/10.3390/molecules24193612 - 07 Oct 2019

Cited by 4 | Viewed by 2526

Abstract

Isoquinoline alkaloids are the main group of secondary metabolites present in Chelidonium majus extracts, and they are still the object of interest of many researchers. Therefore, the development of methods for the investigation and separation of the alkaloids is still an important task. [...] Read more.

Isoquinoline alkaloids are the main group of secondary metabolites present in Chelidonium majus extracts, and they are still the object of interest of many researchers. Therefore, the development of methods for the investigation and separation of the alkaloids is still an important task. In this work, the application potential of a silica-based monolithic column for the separation of alkaloids was assessed. The influence of the organic modifier, temperature, salt concentration, and pH of the eluent on basic chromatographic parameters such as retention, resolution between neighboring peaks, chromatographic plate numbers, and peak asymmetry were investigated. Based on the obtained results, a gradient elution program was developed and used to separate and quantitatively determine the main alkaloids in a Chelidonium majus root extract. Full article

(This article belongs to the Special Issue Chromatographic Science of Natural Products)

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11 pages, 1091 KiB

Open AccessArticle

Polyamidoamide Dendrimers and Cross-Linking Agents for Stabilized Bioenzymatic Resistant Metal-Free Bovine Collagen

by Valentina Beghetto, Vanessa Gatto, Silvia Conca, Noemi Bardella and Alberto Scrivanti

Molecules 2019, 24(19), 3611; https://doi.org/10.3390/molecules24193611 - 07 Oct 2019

Cited by 16 | Viewed by 3968

Abstract

The work reports the use of polyamidoamine dendrimers (PAMAM) and a cross-linking agent, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) or 4-(4,6-dimethoxy[1,3,5]triazin-2-yl)-4-methyl-morpholinium chloride (DMTMM), for the thermal stabilization of dermal bovine collagen. The efficiency of EDC/NHS/PAMAM and DMTMM/PAMAM in the cross-linking of collagen is correlated to [...] Read more.

The work reports the use of polyamidoamine dendrimers (PAMAM) and a cross-linking agent, 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) or 4-(4,6-dimethoxy[1,3,5]triazin-2-yl)-4-methyl-morpholinium chloride (DMTMM), for the thermal stabilization of dermal bovine collagen. The efficiency of EDC/NHS/PAMAM and DMTMM/PAMAM in the cross-linking of collagen is correlated to the increase of the collagen shrinkage temperature (Ts), measured by differential scanning calorimetry (DSC). An alternative enzymatic protocol was adopted to measure the degradability of EDC/NHS/PAMAM tanned hides; these data are correlated to the thermal stability values measured by DSC. In the presence of PAMAMs, EDC/NHS provides very high stabilization of bovine dermal collagen, giving Ts of up to 95 °C, while DMTMM achieves lower stabilization. Preliminary tanning tests carried out in best reaction conditions show that EDC/NHS/PAMAM could be an interesting, environmentally-sustainable tanning system which is completely free of metals, formaldehyde, and phenols. Two new unreported dendrimeric species were synthesized and employed. Full article

(This article belongs to the Special Issue Chemoenzymatic Synthesis and Application)

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15 pages, 3487 KiB

Open AccessFeature PaperArticle

Studies of Halogen Bonding Induced by Pentafluorosulfanyl Aryl Iodides: A Potential Group of Halogen Bond Donors in a Rational Drug Design

by Yuji Sumii, Kenta Sasaki, Seiji Tsuzuki and Norio Shibata

Molecules 2019, 24(19), 3610; https://doi.org/10.3390/molecules24193610 - 07 Oct 2019

Cited by 11 | Viewed by 4054

Abstract

The activation of halogen bonding by the substitution of the pentafluoro-λ⁶-sulfanyl (SF₅) group was studied using a series of SF₅-substituted iodobenzenes. The simulated electrostatic potential values of SF₅-substituted iodobenzenes, the ab initio molecular orbital calculations [...] Read more.

The activation of halogen bonding by the substitution of the pentafluoro-λ⁶-sulfanyl (SF₅) group was studied using a series of SF₅-substituted iodobenzenes. The simulated electrostatic potential values of SF₅-substituted iodobenzenes, the ab initio molecular orbital calculations of intermolecular interactions of SF₅-substituted iodobenzenes with pyridine, and the ¹³C-NMR titration experiments of SF₅-substituted iodobenzenes in the presence of pyridine or tetra (n-butyl) ammonium chloride (TBAC) indicated the obvious activation of halogen bonding, although this was highly dependent on the position of SF₅-substitution on the benzene ring. It was found that 3,5-bis-SF₅-iodobenzene was the most effective halogen bond donor, followed by o-SF₅-substituted iodobenzene, while the m- and p-SF₅ substitutions did not activate the halogen bonding of iodobenzenes. The similar ortho-effect was also confirmed by studies using a series of nitro (NO₂)-substituted iodobenzenes. These observations are in good agreement with the corresponding Mulliken charge of iodine. The 2:1 halogen bonding complex of 3,5-bis-SF₅-iodobenzene and 1,4-diazabicyclo[2.2.2]octane (DABCO) was also confirmed. Since SF₅-containing compounds have emerged as promising novel pharmaceutical and agrochemical candidates, the 3,5-bis-SF₅-iodobenzene unit may be an attractive fragment of rational drug design capable of halogen bonding with biomolecules. Full article

(This article belongs to the Special Issue Fabulous Fluorine in Organic and Medicinal Chemistry)

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21 pages, 3752 KiB

Open AccessArticle

Gold Nanoparticles as Boron Carriers for Boron Neutron Capture Therapy: Synthesis, Radiolabelling and In Vivo Evaluation

by Krishna R. Pulagam, Kiran B. Gona, Vanessa Gómez-Vallejo, Jan Meijer, Carolin Zilberfain, Irina Estrela-Lopis, Zuriñe Baz, Unai Cossío and Jordi Llop

Molecules 2019, 24(19), 3609; https://doi.org/10.3390/molecules24193609 - 07 Oct 2019

Cited by 38 | Viewed by 4402

Abstract

Background: Boron Neutron Capture Therapy (BNCT) is a binary approach to cancer therapy that requires accumulation of boron atoms preferentially in tumour cells. This can be achieved by using nanoparticles as boron carriers and taking advantage of the enhanced permeability and retention [...] Read more.

Background: Boron Neutron Capture Therapy (BNCT) is a binary approach to cancer therapy that requires accumulation of boron atoms preferentially in tumour cells. This can be achieved by using nanoparticles as boron carriers and taking advantage of the enhanced permeability and retention (EPR) effect. Here, we present the preparation and characterization of size and shape-tuned gold NPs (AuNPs) stabilised with polyethylene glycol (PEG) and functionalized with the boron-rich anion cobalt bis(dicarbollide), commonly known as COSAN. The resulting NPs were radiolabelled with ¹²⁴I both at the core and the shell, and were evaluated in vivo in a mouse model of human fibrosarcoma (HT1080 cells) using positron emission tomography (PET). Methods: The thiolated COSAN derivatives for subsequent attachment to the gold surface were synthesized by reaction of COSAN with tetrahydropyran (THP) followed by ring opening using potassium thioacetate (KSAc). Iodination on one of the boron atoms of the cluster was also carried out to enable subsequent radiolabelling of the boron cage. AuNPs grafted with mPEG-SH (5 Kda) and thiolated COSAN were prepared by ligand displacement. Radiolabelling was carried out both at the shell (isotopic exchange) and at the core (anionic absorption) of the NPs using ¹²⁴I to enable PET imaging. Results: Stable gold nanoparticles simultaneously functionalised with PEG and COSAN (PEG-AuNPs@[4]⁻) with hydrodynamic diameter of 37.8 ± 0.5 nm, core diameter of 19.2 ± 1.4 nm and ξ-potential of −18.0 ± 0.7 mV were obtained. The presence of the COSAN on the surface of the NPs was confirmed by Raman Spectroscopy and UV-Vis spectrophotometry. PEG-AuNPs@[4]⁻ could be efficiently labelled with ¹²⁴I both at the core and the shell. Biodistribution studies in a xenograft mouse model of human fibrosarcoma showed major accumulation in liver, lungs and spleen, and poor accumulation in the tumour. The dual labelling approach confirmed the in vivo stability of the PEG-AuNPs@[4]⁻. Conclusions: PEG stabilized, COSAN-functionalised AuNPs could be synthesized, radiolabelled and evaluated in vivo using PET. The low tumour accumulation in the animal model assayed points to the need of tuning the size and geometry of the gold core for future studies. Full article

(This article belongs to the Special Issue Advances in Materials Derived from Polyhedral Boron Clusters)

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13 pages, 852 KiB

Open AccessArticle

In Silico and In Vitro Anti-Helicobacter Pylori Effects of Combinations of Phytochemicals and Antibiotics

by Pedro Fong, Chon-Hou Hao, Chi-Cheng Io, Pou-Io Sin and Li-Rong Meng

Molecules 2019, 24(19), 3608; https://doi.org/10.3390/molecules24193608 - 07 Oct 2019

Cited by 13 | Viewed by 4509

Abstract

Helicobacter pylori infection is a WHO class 1 carcinogenic factor of gastric adenocarcinoma. In the past decades, many studies have demonstrated the increasing trend of antibiotic resistance and pointed out the necessity of new effective treatment. This study was aimed at identifying phytochemicals [...] Read more.

Helicobacter pylori infection is a WHO class 1 carcinogenic factor of gastric adenocarcinoma. In the past decades, many studies have demonstrated the increasing trend of antibiotic resistance and pointed out the necessity of new effective treatment. This study was aimed at identifying phytochemicals that can inhibit H. pylori and possibly serve as adjuvant treatments. Here, in silico molecular docking and drug-like properties analyses were performed to identify potential inhibitors of urease, shikimate kinase and aspartate-semialdehyde dehydrogenase. These three enzymes are targets of the treatment of H. pylori. Susceptibility and synergistic testing were performed on the selected phytochemicals and the positive control antibiotic, amoxicillin. The in-silico study revealed that oroxindin, rosmarinic acid and verbascoside are inhibitors of urease, shikimate kinase and aspartate-semialdehyde dehydrogenase, respectively, in which, oroxindin has the highest potency against H. pylori, indicated by a minimum inhibitory concentration (MIC) value of 50 μg/mL. A combination of oroxindin and amoxicillin demonstrated additive effects against H. pylori, as indicated by a fractional inhibitory concentration (FIC) value of 0.75. This study identified phytochemicals that deserve further investigation for the development of adjuvant therapeutic agents to current antibiotics against H. pylori. Full article

(This article belongs to the Special Issue Antimicrobial Properties of Natural Products)

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11 pages, 1163 KiB

Open AccessArticle

Migration Studies of Two Common Components of UV-curing Inks into Food Simulants

by Miguel A. Lago, Raquel Sendón, Juana Bustos, María T. Nieto, Perfecto Paseiro Losada and Ana Rodríguez-Bernaldo de Quirós

Molecules 2019, 24(19), 3607; https://doi.org/10.3390/molecules24193607 - 07 Oct 2019

Cited by 9 | Viewed by 3055

Abstract

The Rapid Alert System for Food and Feed (RASFF) has reported many cases of different UV curing inks components in foodstuffs during the last few years. These contaminants reach foodstuffs mainly by set-off, their principal migration mechanism from the package. Under this premise, [...] Read more.

The Rapid Alert System for Food and Feed (RASFF) has reported many cases of different UV curing inks components in foodstuffs during the last few years. These contaminants reach foodstuffs mainly by set-off, their principal migration mechanism from the package. Under this premise, this work has tried to characterize the process of migration of two common UV ink components: a photoinitiator (4-Methylbenzophenone) and a coinitiator (Ethyl-4-(dimethylamino) benzoate), from the most common plastic material used in food packaging low-density polyethylene (LDPE) into six different food simulants. The migration kinetics tests were performed at four different common storage temperatures, obtaining the key migration parameters for both molecules: the coefficients of diffusion and partition. The migration process was highly dependent on the storage conditions, the photoinitiator properties and the pH of the foodstuff. Full article

(This article belongs to the Special Issue Food Packaging Materials)

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11 pages, 2313 KiB

Open AccessArticle

Fabrication of pH-Sensitive Tetramycin Releasing Gel and Its Antibacterial Bioactivity against Ralstonia solanacearum

by Xiaozhou Ma, Shunyu Xiang, Huijun Xie, Linhai He, Xianchao Sun, Yongqiang Zhang and Jin Huang

Molecules 2019, 24(19), 3606; https://doi.org/10.3390/molecules24193606 - 07 Oct 2019

Cited by 13 | Viewed by 2957

Abstract

Ralstonia solanacearum (R. solanacearum)-induced bacterial wilt of the nightshade family causes a great loss in agricultural production annually. Although there has been some efficient pesticides against R. solanacearum, inaccurate pesticide releasing according to the onset time of bacterial wilt during [...] Read more.

Ralstonia solanacearum (R. solanacearum)-induced bacterial wilt of the nightshade family causes a great loss in agricultural production annually. Although there has been some efficient pesticides against R. solanacearum, inaccurate pesticide releasing according to the onset time of bacterial wilt during the use of pesticides still hinders the disease management efficiency. Herein, on the basis of the soil pH change during R. solanacearum growth, and pH sensitivity of the Schiff base structure, a pH-sensitive oxidized alginate-based double-crosslinked gel was fabricated as a pesticide carrier. The gel was prepared by crosslinking oxidized sodium alginate (OSA) via adipic dihydrazide (ADH) and Ca²⁺. After loading tetramycin into the gel, it showed a pH-dependent pesticide releasing behavior and anti-bacterial activity against R. solanacearum. Further study also showed that the inhibition rate of the tetramycin-loaded gel was higher than that of industrial pesticide difenoconazole. This work aimed to reduce the difficulty of pesticide administration in the high incidence period of bacterial wilt and we believe it has a great application potential in nightshade production. Full article

(This article belongs to the Section Materials Chemistry)

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20 pages, 1360 KiB

Open AccessArticle

In vitro Fermentation of Polysaccharides from Aloe vera and the Evaluation of Antioxidant Activity and Production of Short Chain Fatty Acids

by Antonio Tornero-Martínez, Rubén Cruz-Ortiz, María Eugenia Jaramillo-Flores, Perla Osorio-Díaz, Sandra Victoria Ávila-Reyes, Guadalupe Monserrat Alvarado-Jasso and Rosalva Mora-Escobedo

Molecules 2019, 24(19), 3605; https://doi.org/10.3390/molecules24193605 - 07 Oct 2019

Cited by 29 | Viewed by 6658

Abstract

Soluble or fermentable fibre has prebiotic effects that can be used in the food industry to modify the composition of microbiota species to benefit human health. Prebiotics mostly target Bifidobacterium and Lactobacillus strains, among others, which can fight against chronic diseases since colonic [...] Read more.

Soluble or fermentable fibre has prebiotic effects that can be used in the food industry to modify the composition of microbiota species to benefit human health. Prebiotics mostly target Bifidobacterium and Lactobacillus strains, among others, which can fight against chronic diseases since colonic fermentation produces short chain fatty acids (SCFAs). The present work studied the changes produced in the fibre and polyphenolic compounds during in vitro digestion of gel (AV) and a polysaccharide extract (AP) from Aloe vera, after which, these fractions were subjected to in vitro colonic fermentation to evaluate the changes in antioxidant capacity and SCFAs production during the fermentation. The results showed that the phenolic compounds increased during digestion, but were reduced in fermentation, as a consequence, the antioxidant activity increased significantly in AV and AP after the digestion. On the other hand, during in vitro colon fermentation, the unfermented fibre of AV and AP responded as lactulose and the total volume of gas produced, which indicates the possible use of Aloe vera and polysaccharide extract as prebiotics. Full article

(This article belongs to the Special Issue Food Bioactives: Chemical Challenges and Bio-Opportunities)

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27 pages, 10229 KiB

Open AccessEditor’s ChoiceReview

Ferrocene-Based Compounds with Antimalaria/Anticancer Activity

by Sijongesonke Peter and Blessing Atim Aderibigbe

Molecules 2019, 24(19), 3604; https://doi.org/10.3390/molecules24193604 - 07 Oct 2019

Cited by 96 | Viewed by 8188

Abstract

Malaria and cancer are chronic diseases. The challenge with drugs available for the treatment of these diseases is drug toxicity and resistance. Ferrocene is a potent organometallic which have been hybridized with other compounds resulting in compounds with enhanced biological activity such as [...] Read more.

Malaria and cancer are chronic diseases. The challenge with drugs available for the treatment of these diseases is drug toxicity and resistance. Ferrocene is a potent organometallic which have been hybridized with other compounds resulting in compounds with enhanced biological activity such as antimalarial and anticancer. Drugs such as ferroquine were developed from ferrocene and chloroquine. It was tested in the 1990s as an antimalarial and is still an effective antimalarial. Many researchers have reported ferrocene compounds as potent compounds useful as anticancer and antimalarial agents when hybridized with other pharmaceutical scaffolds. This review will be focused on compounds with ferrocene moieties that exhibit either an anticancer or antimalarial activity. Full article

(This article belongs to the Special Issue Metal-Based Drugs)

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14 pages, 1805 KiB

Open AccessArticle

High-Throughput ¹H-Nuclear Magnetic Resonance-Based Screening for the Identification and Quantification of Heartwood Diterpenic Acids in Four Black Pine (Pinus nigra Arn.) Marginal Provenances in Greece

by Kostas Ioannidis, Eleni Melliou and Prokopios Magiatis

Molecules 2019, 24(19), 3603; https://doi.org/10.3390/molecules24193603 - 07 Oct 2019

Cited by 13 | Viewed by 3445

Abstract

A high-throughput quantitative Nuclear Magnetic Resonance ¹H-NMR method was developed and applied to screen the quantity of the diterpenic resin acids in the heartwood of black pine, due to the renewed scientific interest in their medicinal properties and use in various diseases [...] Read more.

A high-throughput quantitative Nuclear Magnetic Resonance ¹H-NMR method was developed and applied to screen the quantity of the diterpenic resin acids in the heartwood of black pine, due to the renewed scientific interest in their medicinal properties and use in various diseases treatment. The 260 samples were taken from Pinus nigra clones, selected from four provenances of the Peloponnese (Greece), participating in a 35-year-old clonal seed orchard. Total resin acids per dry heartwood weight (dhw) varied greatly, ranging from 30.05 to 424.70 mg/g_dhw (average 219.98 mg/g_dhw). Abietic was the predominant acid (76.77 mg/g_dhw), followed by palustric acid (47.94 mg/g_dhw), neoabietic acid (39.34 mg/g_dhw), and pimaric acid (22.54 mg/g_dhw). Dehydroabietic acid was at moderate levels (11.69 mg/g_dhw), while levopimaric, isopimaric, and sandaracopimaric acids were in lower concentrations. The resin acid fraction accounted for 72.33% of the total acetone extractives. Stilbenes were presented in significant quantities (19.70%). The resin acid content was composed mainly of the abietane type resin acids (83.56%). Peloponnesian Pinus nigra heartwood was found to be the richest source of resin acids identified to date and is considered the best natural source for the production of such bioactive extracts. The results indicate a high potential for effective selection and advanced breeding of pharmaceutical and high economic value bioactive substances from Pinus nigra clones. Full article

(This article belongs to the Special Issue Terpenes and Terpene Derivatives)

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10 pages, 841 KiB

Open AccessArticle

Identification of Cannabis sativa L. (hemp) Retailers by Means of Multivariate Analysis of Cannabinoids

by Sara Palmieri, Marcello Mascini, Antonella Ricci, Federico Fanti, Chiara Ottaviani, Claudio Lo Sterzo and Manuel Sergi

Molecules 2019, 24(19), 3602; https://doi.org/10.3390/molecules24193602 - 07 Oct 2019

Cited by 10 | Viewed by 4692

Abstract

In this work, the concentration of nine cannabinoids, six neutral cannabinoids (THC, CBD, CBC, CBG, CBN and CBDV) and three acidic cannabinoids (THCA CBGA and CBDA), was used to identify the Italian retailers of Cannabis sativa L. (hemp), reinforcing the idea that the [...] Read more.

In this work, the concentration of nine cannabinoids, six neutral cannabinoids (THC, CBD, CBC, CBG, CBN and CBDV) and three acidic cannabinoids (THCA CBGA and CBDA), was used to identify the Italian retailers of Cannabis sativa L. (hemp), reinforcing the idea that the practice of categorizing hemp samples only using THC and CBD is inadequate. A high-performance liquid chromatography/high-resolution mass spectrometry (HPLC-MS/MS) method was developed for screening and simultaneously analyzing the nine cannabinoids in 161 hemp samples sold by four retailers located in different Italian cities. The hemp samples dataset was analyzed by univariate and multivariate analysis with the aim to identify the hemp retailers without any other information on the hemp samples like Cannabis strains, seeds, soil and cultivation characteristics, geographical origin, product storage, etc. The univariate analysis highlighted that the hemp samples could not be differentiated by using any of the nine cannabinoids analyzed. To evaluate the real efficiency of the discrimination among the four hemp retailers a partial least squares discriminant analysis (PLS-DA) was applied. The PLS-DA results showed a very good discrimination between the four hemp retailers with an explained variance of 100% and low classification errors in both calibration (5%) and cross validation (6%). A total of 92% of the hemp samples were correctly classified by the cannabinoid variables in both fitting and cross validation. This work contributed to show that an analytical method coupled with multivariate analysis can be used as a powerful tool for forensic purposes. Full article

(This article belongs to the Special Issue Cannabinergic Ligands: Chemistry, Pharmacology and Therapeutic Potential)

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