15 pages, 6373 KiB  
Article
Preparation of Bamboo-Based Hierarchical Porous Carbon Modulated by FeCl3 towards Efficient Copper Adsorption
by Yixin Zhang, Guofeng Qiu, Rumeng Wang, Yang Guo, Fanhui Guo and Jianjun Wu
Molecules 2021, 26(19), 6014; https://doi.org/10.3390/molecules26196014 - 3 Oct 2021
Cited by 9 | Viewed by 3031
Abstract
Using bamboo powder biochar as raw material, high-quality meso/microporous controlled hierarchical porous carbon was prepared—through the catalysis of Fe3+ ions loading, in addition to a chemical activation method—and then used to adsorb copper ions in an aqueous solution. The preparation process mainly [...] Read more.
Using bamboo powder biochar as raw material, high-quality meso/microporous controlled hierarchical porous carbon was prepared—through the catalysis of Fe3+ ions loading, in addition to a chemical activation method—and then used to adsorb copper ions in an aqueous solution. The preparation process mainly included two steps: load-alkali leaching and chemical activation. The porosity characteristics (specific surface area and mesopore ratio) were controlled by changing the K2CO3 impregnation ratio, activation temperature, and Fe3+ ions loading during the activation process. Additionally, three FBPC samples with different pore structures and characteristics were studied for copper adsorption. The results indicate that the adsorption performance of the bamboo powder biochar FBPC material was greatly affected by the meso/micropore ratio. FBPC 2.5-900-2%, impregnated at a K2CO3: biochar ratio of 2.5 and a Fe3+: biochar mass ratio of 2%, and activated at 900 °C for 2 h in N2 atmosphere, has a very high specific surface area of 1996 m2 g−1 with a 58.1% mesoporous ratio. Moreover, it exhibits an excellent adsorption capacity of 256 mg g−1 and rapid adsorption kinetics for copper ions. The experimental results show that it is feasible to control the hierarchical pore structure of bamboo biochar-derived carbons as a high-performance adsorbent to remove copper ions from water. Full article
(This article belongs to the Special Issue Barrier and Functional Materials from Waste Materials for Pollutants)
Show Figures

Figure 1

16 pages, 46213 KiB  
Article
High Substitution Synthesis of Carboxymethyl Chitosan for Properties Improvement of Carboxymethyl Chitosan Films Depending on Particle Sizes
by Sarinthip Thanakkasaranee, Kittisak Jantanasakulwong, Yuthana Phimolsiripol, Noppol Leksawasdi, Phisit Seesuriyachan, Thanongsak Chaiyaso, Pensak Jantrawut, Warintorn Ruksiriwanich, Sarana Rose Sommano, Winita Punyodom, Alissara Reungsang, Thi Minh Phuong Ngo, Parichat Thipchai, Wirongrong Tongdeesoontorn and Pornchai Rachtanapun
Molecules 2021, 26(19), 6013; https://doi.org/10.3390/molecules26196013 - 3 Oct 2021
Cited by 33 | Viewed by 5848
Abstract
This study investigated the effect of chitosan particle sizes on the properties of carboxymethyl chitosan (CMCh) powders and films. Chitosan powders with different particle sizes (75, 125, 250, 450 and 850 µm) were used to synthesize the CMCh powders. The yield, degree of [...] Read more.
This study investigated the effect of chitosan particle sizes on the properties of carboxymethyl chitosan (CMCh) powders and films. Chitosan powders with different particle sizes (75, 125, 250, 450 and 850 µm) were used to synthesize the CMCh powders. The yield, degree of substitution (DS), and water solubility of the CMCh powders were then determined. The CMCh films prepared with CMCh based on chitosan with different particle sizes were fabricated by a solution casting technique. The water solubility, mechanical properties, and water vapor transmission rate (WVTR) of the CMCh films were measured. As the chitosan particle size decreased, the yield, DS, and water solubility of the synthesized CMCh powders increased. The increase in water solubility was due to an increase in the polarity of the CMCh powder, from a higher conversion of chitosan into CMCh. In addition, the higher conversion of chitosan was also related to a higher surface area in the substitution reaction provided by chitosan powder with a smaller particle size. As the particle size of chitosan decreased, the tensile strength, elongation at break, and WVTR of the CMCh films increased. This study demonstrated that a greater improvement in water solubility of the CMCh powders and films can be achieved by using chitosan powder with a smaller size. Full article
(This article belongs to the Special Issue Chitin and Chitosan: Derivatives and Applications II)
Show Figures

Graphical abstract

16 pages, 2911 KiB  
Article
Structural Basis for PPARs Activation by The Dual PPARα/γ Agonist Sanguinarine: A Unique Mode of Ligand Recognition
by Siyu Tian, Rui Wang, Shuming Chen, Jialing He, Weili Zheng and Yong Li
Molecules 2021, 26(19), 6012; https://doi.org/10.3390/molecules26196012 - 3 Oct 2021
Cited by 8 | Viewed by 3239
Abstract
Peroxisome proliferator-activated receptors (PPARs) play crucial roles in glucose and lipid metabolism and inflammation. Sanguinarine is a natural product that is isolated from Sanguinaria Canadensis, a potential therapeutic agent for intervention in chronic diseases. In this study, biochemical and cell-based promoter-reporter gene assays [...] Read more.
Peroxisome proliferator-activated receptors (PPARs) play crucial roles in glucose and lipid metabolism and inflammation. Sanguinarine is a natural product that is isolated from Sanguinaria Canadensis, a potential therapeutic agent for intervention in chronic diseases. In this study, biochemical and cell-based promoter-reporter gene assays revealed that sanguinarine activated both PPARα and PPARγ, and enhanced their transcriptional activity; thus, sanguinarine was identified as a dual agonist of PPARα/γ. Similar to fenofibrate, sanguinarine upregulates the expression of PPARα-target genes in hepatocytes. Sanguinarine also modulates the expression of key PPARγ-target genes and promotes adipocyte differentiation, but with a lower adipogenic activity compared with rosiglitazone. We report the crystal structure of sanguinarine bound to PPARα, which reveals a unique ligand-binding mode of sanguinarine, dissimilar to the classic Y-shaped binding pocket, which may represent a new pharmacophore that can be optimized for selectively targeting PPARα. Further structural and functional studies uncover the molecular basis for the selectivity of sanguinarine toward PPARα/γ among all three PPARs. In summary, our study identifies a PPARα/γ dual agonist with a unique ligand-binding mode, and provides a promising and viable novel template for the design of dual-targeting PPARs ligands. Full article
(This article belongs to the Section Chemical Biology)
Show Figures

Figure 1

15 pages, 2183 KiB  
Article
Improved Stability of a Stable Crystal Form C of 6S-5-Methyltetrahydrofolate Calcium Salt, Method Development and Validation of an LC–MS/MS Method for Rat Pharmacokinetic Comparison
by Zenglin Lian, Hong Chen, Kang Liu, Qianghua Jia, Feng Qiu and Yongzhi Cheng
Molecules 2021, 26(19), 6011; https://doi.org/10.3390/molecules26196011 - 3 Oct 2021
Cited by 5 | Viewed by 3881
Abstract
Folate is a vitamin beneficial for humans that plays an important role in metabolism, but it cannot be well supplemented by food; it is necessary to supplement it in other ways. Based on this consideration, a novel crystal form C of 6S-5-methyltetrahydrofolate calcium [...] Read more.
Folate is a vitamin beneficial for humans that plays an important role in metabolism, but it cannot be well supplemented by food; it is necessary to supplement it in other ways. Based on this consideration, a novel crystal form C of 6S-5-methyltetrahydrofolate calcium salt (MTHF CAC) was obtained. To explore the difference between MTHF CAC and the crystal form Ⅰ of 6S-5-methyltetrahydrofolate calcium salt (MTHF CA) as well as an amorphous product of 6S-5-methyltetrahydrofolate glucosamine salt (MTHF GA), their stability and pharmacokinetic behaviours were compared. The results of high-performance liquid chromatography coupled with ultraviolet detection analysis indicated that MTHF CAC showed a better stability than MTHF CA and MTHF GA. After oral administration of MTHF CAC, MTHF CA, and MTHF GA to male rats, the MTHF concentrations were analysed using a validated liquid chromatography–tandem mass spectrometry, and the pharmacokinetic parameters were compared. The mean residence times (0–t) of MTHF CAC, MTHF CA, and MTHF GA were 3.7 ± 1.9 h, 1.0 ± 0.2 h (p < 0.01), and 1.5 ± 0.3 h (p < 0.05), respectively. The relative bioavailability of MTHF CAC was calculated to be 351% and 218% compared with MTHF CA and MTHF GA, respectively, which suggests that MTHF CAC can be better absorbed and utilized for a longer period of time. Full article
Show Figures

Graphical abstract

20 pages, 3046 KiB  
Article
Workflow to Investigate Subtle Differences in Wine Volatile Metabolome Induced by Different Root Systems and Irrigation Regimes
by Mani Awale, Connie Liu and Misha T. Kwasniewski
Molecules 2021, 26(19), 6010; https://doi.org/10.3390/molecules26196010 - 3 Oct 2021
Cited by 8 | Viewed by 4091
Abstract
To allow for a broad survey of subtle metabolic shifts in wine caused by rootstock and irrigation, an integrated metabolomics-based workflow followed by quantitation was developed. This workflow was particularly useful when applied to a poorly studied red grape variety cv. Chambourcin. Allowing [...] Read more.
To allow for a broad survey of subtle metabolic shifts in wine caused by rootstock and irrigation, an integrated metabolomics-based workflow followed by quantitation was developed. This workflow was particularly useful when applied to a poorly studied red grape variety cv. Chambourcin. Allowing volatile metabolites that otherwise may have been missed with a targeted analysis to be included, this approach allowed deeper modeling of treatment differences which then could be used to identify important compounds. Wines produced on a per vine basis, over two years, were analyzed using SPME-GC-MS/MS. From the 382 and 221 features that differed significantly among rootstocks in 2017 and 2018, respectively, we tentatively identified 94 compounds by library search and retention index, with 22 confirmed and quantified using authentic standards. Own-rooted Chambourcin differed from other root systems for multiple volatile compounds with fewer differences among grafted vines. For example, the average concentration of β-Damascenone present in own-rooted vines (9.49 µg/L) was significantly lower in other rootstocks (8.59 µg/L), whereas mean Linalool was significantly higher in 1103P rootstock compared to own-rooted. β-Damascenone was higher in regulated deficit irrigation (RDI) than other treatments. The approach outlined not only was shown to be useful for scientific investigation, but also in creating a protocol for analysis that would ensure differences of interest to the industry are not missed. Full article
(This article belongs to the Section Analytical Chemistry)
Show Figures

Graphical abstract

16 pages, 3396 KiB  
Article
Photodegradation of Riboflavin under Alkaline Conditions: What Can Gas-Phase Photolysis Tell Us about What Happens in Solution?
by Natalie G. K. Wong, Chris Rhodes and Caroline E. H. Dessent
Molecules 2021, 26(19), 6009; https://doi.org/10.3390/molecules26196009 - 3 Oct 2021
Cited by 9 | Viewed by 5537
Abstract
The application of electrospray ionisation mass spectrometry (ESI-MS) as a direct method for detecting reactive intermediates is a technique of developing importance in the routine monitoring of solution-phase reaction pathways. Here, we utilise a novel on-line photolysis ESI-MS approach to detect the photoproducts [...] Read more.
The application of electrospray ionisation mass spectrometry (ESI-MS) as a direct method for detecting reactive intermediates is a technique of developing importance in the routine monitoring of solution-phase reaction pathways. Here, we utilise a novel on-line photolysis ESI-MS approach to detect the photoproducts of riboflavin in aqueous solution under mildly alkaline conditions. Riboflavin is a constituent of many food products, so its breakdown processes are of wide interest. Our on-line photolysis setup allows for solution-phase photolysis to occur within a syringe using UVA LEDs, immediately prior to being introduced into the mass spectrometer via ESI. Gas-phase photofragmentation studies via laser-interfaced mass spectrometry of deprotonated riboflavin, [RF − H], the dominant solution-phase species under the conditions of our study, are presented alongside the solution-phase photolysis. The results obtained illustrate the extent to which gas-phase photolysis methods can inform our understanding of the corresponding solution-phase photochemistry. We determine that the solution-phase photofragmentation observed for [RF − H] closely mirrors the gas-phase photochemistry, with the dominant m/z 241 condensed-phase photoproduct also being observed in gas-phase photodissociation. Further gas-phase photoproducts are observed at m/z 255, 212, and 145. The value of exploring both the gas- and solution-phase photochemistry to characterise photochemical reactions is discussed. Full article
(This article belongs to the Special Issue Women in Physical Chemistry)
Show Figures

Graphical abstract

15 pages, 2025 KiB  
Article
Concise Large-Scale Synthesis of Tomatidine, A Potent Antibiotic Natural Product
by Chad Normandin and Pierre-Luc Boudreault
Molecules 2021, 26(19), 6008; https://doi.org/10.3390/molecules26196008 - 3 Oct 2021
Cited by 5 | Viewed by 4562
Abstract
Tomatidine has recently generated a lot of interest amongst the pharmacology, medicine, and biology fields of study, especially for its newfound activity as an antibiotic agent capable of targeting multiple strains of bacteria. In the light of its low natural abundance and high [...] Read more.
Tomatidine has recently generated a lot of interest amongst the pharmacology, medicine, and biology fields of study, especially for its newfound activity as an antibiotic agent capable of targeting multiple strains of bacteria. In the light of its low natural abundance and high cost, an efficient and scalable multi-gram synthesis of tomatidine has been developed. This synthesis uses a Suzuki–Miyaura-type coupling reaction as a key step to graft an enantiopure F-ring side chain to the steroidal scaffold of the natural product, which was accessible from low-cost and commercially available diosgenin. A Lewis acid-mediated spiroketal opening followed by an azide substitution and reduction sequence is employed to generate the spiroaminoketal motif of the natural product. Overall, this synthesis produced 5.2 g in a single pass in 15 total steps and 15.2% yield using a methodology that is atom economical, scalable, and requires no flash chromatography purifications. Full article
(This article belongs to the Special Issue Total Synthesis of Natural Products)
Show Figures

Scheme 1

9 pages, 798 KiB  
Communication
On the Squalene Content of CV Chondrolia Chalkidikis and Chalkidiki (Greece) Virgin Olive Oil
by Aspasia Mastralexi and Maria Z. Tsimidou
Molecules 2021, 26(19), 6007; https://doi.org/10.3390/molecules26196007 - 3 Oct 2021
Cited by 13 | Viewed by 2928
Abstract
This work is a continuation of efforts to establish the nutritional profile of virgin olive oil (VOO) from cv. Chondrolia Chalkidikis and Chalkidiki and to strengthen its positioning in the global VOO landscape. VOOs produced at an industrial scale in different olive mills [...] Read more.
This work is a continuation of efforts to establish the nutritional profile of virgin olive oil (VOO) from cv. Chondrolia Chalkidikis and Chalkidiki and to strengthen its positioning in the global VOO landscape. VOOs produced at an industrial scale in different olive mills of the Chalkidiki (Greece) regional unit as well as VOOs obtained at the laboratory scale from drupes of different maturity stages for four consecutive harvesting years were examined for their squalene (SQ) content using both HPLC and GC procedures. The mean values of SQ were found to be 4228 (HPLC) and 4865 (GC) mg/kg oil (n = 15) and were of the same magnitude as that in VOOs from cv Koroneiki (4134 mg/kg, n = 23). Storage of VOOs in the dark at room temperature for 18 months indicated an insignificant mean SQ content loss (~2%) in comparison to a mean loss of 26% for alpha-tocopherol content. This finding strengthens our view that SQ does not act as a radical scavenger that donates hydrogen atoms to the latter. The four consecutive harvest years studied indicated a clear declining trend in VOO SQ concentration upon olive ripening. To our knowledge, this is the first systematic work concerning the SQ content of Chondrolia Chalkidikis and Chalkidiki VOOs. Full article
(This article belongs to the Special Issue Characterization of Olive Products from Greece)
Show Figures

Graphical abstract

14 pages, 2596 KiB  
Article
Overexpression of the Gene Encoding Neurosecretory Protein GL Precursor Prevents Excessive Fat Accumulation in the Adipose Tissue of Mice Fed a Long-Term High-Fat Diet
by Keisuke Fukumura, Yuki Narimatsu, Shogo Moriwaki, Eiko Iwakoshi-Ukena, Megumi Furumitsu and Kazuyoshi Ukena
Molecules 2021, 26(19), 6006; https://doi.org/10.3390/molecules26196006 - 3 Oct 2021
Cited by 4 | Viewed by 2683
Abstract
We previously identified a novel small hypothalamic protein, neurosecretory protein GL (NPGL), which induces feeding behavior and fat accumulation in rodents depending on their diet. In the present study, we explored the effects of NPGL on feeding behavior and energy metabolism in mice [...] Read more.
We previously identified a novel small hypothalamic protein, neurosecretory protein GL (NPGL), which induces feeding behavior and fat accumulation in rodents depending on their diet. In the present study, we explored the effects of NPGL on feeding behavior and energy metabolism in mice placed on a long-term high-fat diet with 60% calories from fat (HFD 60). Overexpression of the NPGL precursor gene (Npgl) over 18 weeks increased food intake and weight. The weekly weight gain of Npgl-overexpressing mice was higher than that of controls until 7 weeks from induction of overexpression, after which it ceased to be so. Oral glucose tolerance tests showed that Npgl overexpression maintained glucose tolerance and increased blood insulin levels, and intraperitoneal insulin tolerance tests showed that it maintained insulin sensitivity. At the experimental endpoint, Npgl overexpression was associated with increased mass of the perirenal white adipose tissue (WAT) and decreased mass of the epididymal WAT (eWAT), resulting in little effect on the total WAT mass. These results suggest that under long-term HFD 60 feeding, Npgl overexpression may play a role in avoiding metabolic disturbance both by accelerating energy storage and by suppressing excess fat accumulation in certain tissues, such as the eWAT. Full article
(This article belongs to the Special Issue Neuropeptides: From Physiology to Therapeutic Applications)
Show Figures

Figure 1

26 pages, 11845 KiB  
Review
Fatty Acids and Their Metal Salts: A Review of Their Infrared Spectra in Light of Their Presence in Cultural Heritage
by Anna Filopoulou, Sophia Vlachou and Stamatis C. Boyatzis
Molecules 2021, 26(19), 6005; https://doi.org/10.3390/molecules26196005 - 3 Oct 2021
Cited by 74 | Viewed by 12531
Abstract
In a cultural heritage context, fatty acids are usually found as breakdown products of lipid-containing organic remains in archaeological findings, binders in aged oil paintings, and additives in modern art-related materials. They may further interact with the ionic environment transforming into metal soaps, [...] Read more.
In a cultural heritage context, fatty acids are usually found as breakdown products of lipid-containing organic remains in archaeological findings, binders in aged oil paintings, and additives in modern art-related materials. They may further interact with the ionic environment transforming into metal soaps, a process that has been recognized as a threat in aged paintings but has received less attention in archaeological objects. The investigation of the above related categories of materials with infrared spectroscopy can provide an overall picture of the organic components’ identity and demonstrate their condition and prehistory. The capability of investigating and distinguishing fatty acids and their metal soaps through their rich infrared features, such as the acidic carbonyl, the carboxylate shifts, the variable splits of alkyl chain stretching, bending, twisting, wagging, and rocking vibrations, as well as the hydroxyl peak envelopes and acid dimer bands, allows for their direct detailed characterization. This paper reviews the infrared spectra of selected saturated fatty monoacids and diacids, and their corresponding sodium, calcium, and zinc salts and, supported by newly recorded data, highlights the significance of their spectroscopic features. Full article
(This article belongs to the Special Issue Advances in Analytical Strategies to Study Cultural Heritage Samples)
Show Figures

Graphical abstract

12 pages, 1921 KiB  
Article
Selected Class of Enamides Bearing Nitro Functionality as Dual-Acting with Highly Selective Monoamine Oxidase-B and BACE1 Inhibitors
by Anusree Venkidath, Jong Min Oh, Sanal Dev, Elham Amin, Shebina P. Rasheed, Ajeesh Vengamthodi, Nicola Gambacorta, Ahmed Khames, Mohamed A. Abdelgawad, Ginson George, Orazio Nicolotti, Hoon Kim and Bijo Mathew
Molecules 2021, 26(19), 6004; https://doi.org/10.3390/molecules26196004 - 3 Oct 2021
Cited by 10 | Viewed by 2878
Abstract
A small series of nitro group-bearing enamides was designed, synthesized (NEA1NEA5), and evaluated for their inhibitory profiles of monoamine oxidases (MAOs) and β-site amyloid precursor protein cleaving enzyme 1 (β-secretase, BACE1). Compounds NEA3 and NEA1 exhibited a more potent [...] Read more.
A small series of nitro group-bearing enamides was designed, synthesized (NEA1NEA5), and evaluated for their inhibitory profiles of monoamine oxidases (MAOs) and β-site amyloid precursor protein cleaving enzyme 1 (β-secretase, BACE1). Compounds NEA3 and NEA1 exhibited a more potent MAO-B inhibition (IC50 value = 0.0092 and 0.016 µM, respectively) than the standards (IC50 value = 0.11 and 0.14 µM, respectively, for lazabemide and pargyline). Moreover, NEA3 and NEA1 showed greater selectivity index (SI) values toward MAO-B over MAO-A (SI of >1652.2 and >2500.0, respectively). The inhibition and kinetics studies suggested that NEA3 and NEA1 are reversible and competitive inhibitors with Ki values of 0.013 ± 0.005 and 0.0049 ± 0.0002 µM, respectively, for MAO-B. In addition, both NEA3 and NEA1 showed efficient BACE1 inhibitions with IC50 values of 8.02 ± 0.13 and 8.21 ± 0.03 µM better than the standard quercetin value (13.40 ± 0.04 µM). The parallel artificial membrane permeability assay (PAMPA) method demonstrated that all the synthesized derivatives can cross the blood–brain barrier (BBB) successfully. Docking analyses were performed by employing an induced-fit docking approach in the GLIDE module of Schrodinger, and the results were in agreement with their in vitro inhibitory activities. The present study resulted in the discovery of potent dual inhibitors toward MAO-B and BACE1, and these lead compounds can be fruitfully explored for the generation of newer, clinically active agents for the treatment of neurodegenerative disorders. Full article
Show Figures

Figure 1

12 pages, 3352 KiB  
Article
Altered Glycosylation of Human Alpha-1-Acid Glycoprotein as a Biomarker for Malignant Melanoma
by Dávid Virág, Tibor Kremmer, Kende Lőrincz, Norbert Kiss, Antal Jobbágy, Szabolcs Bozsányi, Lili Gulyás, Norbert Wikonkál, Gitta Schlosser, Adina Borbély, Zsófia Huba, Borbála Dalmadi Kiss, István Antal and Krisztina Ludányi
Molecules 2021, 26(19), 6003; https://doi.org/10.3390/molecules26196003 - 3 Oct 2021
Cited by 11 | Viewed by 3513
Abstract
A high-resolution HILIC-MS/MS method was developed to analyze anthranilic acid derivatives of N-glycans released from human serum alpha-1-acid glycoprotein (AGP). The method was applied to samples obtained from 18 patients suffering from high-risk malignant melanoma as well as 19 healthy individuals. It [...] Read more.
A high-resolution HILIC-MS/MS method was developed to analyze anthranilic acid derivatives of N-glycans released from human serum alpha-1-acid glycoprotein (AGP). The method was applied to samples obtained from 18 patients suffering from high-risk malignant melanoma as well as 19 healthy individuals. It enabled the identification of 102 glycan isomers separating isomers that differ only in sialic acid linkage (α-2,3, α-2,6) or in fucose positions (core, antenna). Comparative assessment of the samples revealed that upregulation of certain fucosylated glycans and downregulation of their nonfucosylated counterparts occurred in cancer patients. An increased ratio of isomers with more α-2,6-linked sialic acids was also observed. Linear discriminant analysis (LDA) combining 10 variables with the highest discriminatory power was employed to categorize the samples based on their glycosylation pattern. The performance of the method was tested by cross-validation, resulting in an overall classification success rate of 96.7%. The approach presented here is significantly superior to serological marker S100B protein in terms of sensitivity and negative predictive power in the population studied. Therefore, it may effectively support the diagnosis of malignant melanoma as a biomarker. Full article
(This article belongs to the Section Analytical Chemistry)
Show Figures

Graphical abstract

23 pages, 2357 KiB  
Article
Olive Pomace Phenolic Compounds Stability and Safety Evaluation: From Raw Material to Future Ophthalmic Applications
by Nikolaos Katsinas, Amalia Enríquez-de-Salamanca, Andreia Bento da Silva, Maria Rosário Bronze and Soraya Rodríguez-Rojo
Molecules 2021, 26(19), 6002; https://doi.org/10.3390/molecules26196002 - 2 Oct 2021
Cited by 9 | Viewed by 6029
Abstract
Nowadays, increasing interest in olive pomace (OP) valorization aims to improve olive’s industry sustainability. Interestingly, several studies propose a high-value application for OP extracts containing its main phenolic compounds, hydroxytyrosol and oleuropein, as therapy for ocular surface diseases. In this work, the stability [...] Read more.
Nowadays, increasing interest in olive pomace (OP) valorization aims to improve olive’s industry sustainability. Interestingly, several studies propose a high-value application for OP extracts containing its main phenolic compounds, hydroxytyrosol and oleuropein, as therapy for ocular surface diseases. In this work, the stability and accessibility of OP total phenolic and flavonoid content, main representative compounds, and antioxidant activity were assessed under different pretreatment conditions. Among them, lyophilization and supercritical CO2 extraction were found to increase significantly most responses measured in the produced extracts. Two selected extracts (CONV and OPT3) were obtained by different techniques (conventional and pressurized liquid extraction); Their aqueous solutions were characterized by HPLC-DAD-MS/MS. Additionally, their safety and stability were evaluated according to EMA requirements towards their approval as ophthalmic products: their genotoxic effect on ocular surface cells and their 6-months storage stability at 4 different temperature/moisture conditions (CPMP/ICH/2736/99), together with pure hydroxytyrosol and oleuropein solutions. The concentration of hydroxytyrosol and oleuropein in pure or extract solutions was tracked, and possible degradation products were putatively identified by HPLC-DAD-MS/MS. Hydroxytyrosol and oleuropein had different stability as standard or extract solutions, with oleuropein also showing different degradation profile. All compounds/extracts were safe for ophthalmic use at the concentrations tested. Full article
Show Figures

Figure 1

11 pages, 2140 KiB  
Article
The Evidence of the Bystander Effect after Bleomycin Electrotransfer and Irreversible Electroporation
by Paulius Ruzgys, Neringa Barauskaitė, Vitalij Novickij, Jurij Novickij and Saulius Šatkauskas
Molecules 2021, 26(19), 6001; https://doi.org/10.3390/molecules26196001 - 2 Oct 2021
Cited by 8 | Viewed by 2734
Abstract
One of current applications of electroporation is electrochemotherapy and electroablation for local cancer treatment. Both of these electroporation modalities share some similarities with radiation therapy, one of which could be the bystander effect. In this study, we aimed to investigate the role of [...] Read more.
One of current applications of electroporation is electrochemotherapy and electroablation for local cancer treatment. Both of these electroporation modalities share some similarities with radiation therapy, one of which could be the bystander effect. In this study, we aimed to investigate the role of the bystander effect following these electroporation-based treatments. During direct CHO-K1 cell treatment, cells were electroporated using one 100 µs duration square wave electric pulse at 1400 V/cm (for bleomycin electrotransfer) or 2800 V/cm (for irreversible electroporation). To evaluate the bystander effect, the medium was taken from directly treated cells after 24 h incubation and applied on unaffected cells. Six days after the treatment, cell viability and colony sizes were evaluated using the cell colony formation assay. The results showed that the bystander effect after bleomycin electrotransfer had a strong negative impact on cell viability and cell colony size, which decreased to 2.8% and 23.1%, respectively. On the contrary, irreversible electroporation induced a strong positive bystander effect on cell viability, which increased to 149.3%. In conclusion, the results presented may serve as a platform for further analysis of the bystander effect after electroporation-based therapies and may ultimately lead to refined application of these therapies in clinics. Full article
(This article belongs to the Special Issue Novel Physical and Chemical Methods for Facilitated Drug Delivery)
Show Figures

Graphical abstract

17 pages, 2331 KiB  
Article
The Reactions of 6-(Hydroxymethyl)-2,2-dimethyl-1-azaspiro[4.4]nonanes with Methanesulfonyl Chloride or PPh3-CBr4
by Yulia V. Khoroshunova, Denis A. Morozov, Andrey I. Taratayko, Sergey A. Dobrynin, Ilia V. Eltsov, Tatyana V. Rybalova, Yulia S. Sotnikova, Dmitriy N. Polovyanenko, Nargiz B. Asanbaeva and Igor A. Kirilyuk
Molecules 2021, 26(19), 6000; https://doi.org/10.3390/molecules26196000 - 2 Oct 2021
Cited by 2 | Viewed by 3580
Abstract
Activation of a hydroxyl group towards nucleophilic substitution via reaction with methanesulfonyl chloride or PPh3-CBr4 system is a commonly used pathway to various functional derivatives. The reactions of (5R(S),6R(S))-1-X-6-(hydroxymethyl)-2,2-dimethyl- 1-azaspiro[4.4]nonanes 1a [...] Read more.
Activation of a hydroxyl group towards nucleophilic substitution via reaction with methanesulfonyl chloride or PPh3-CBr4 system is a commonly used pathway to various functional derivatives. The reactions of (5R(S),6R(S))-1-X-6-(hydroxymethyl)-2,2-dimethyl- 1-azaspiro[4.4]nonanes 1ad (X = O·; H; OBn, OBz) with MsCl/NR3 or PPh3-CBr4 were studied. Depending on substituent X, the reaction afforded hexahydro-1H,6H-cyclopenta[c]pyrrolo[1,2-b]isoxazole (2) (for X = O), a mixture of 2 and octahydrocyclopenta[c]azepines (46) (for X = OBn, OBz), or perhydro-cyclopenta[2,3]azeto[1,2-a]pyrrol (3) (for X = H) derivatives. Alkylation of the latter with MeI with subsequent Hofmann elimination afforded 2,3,3-trimethyl-1,2,3,4,5,7,8,8a-octahydrocyclopenta[c]azepine with 56% yield. Full article
Show Figures

Figure 1