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1.
Curr Issues Mol Biol ; 46(10): 10806-10828, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39451522

RESUMO

Triple-negative breast cancer (TNBC) accounts for approximately 20% of all breast cancer cases and is characterized by a lack of estrogen, progesterone, and human epidermal growth factor 2 receptors. Current targeted medicines have been unsuccessful due to this absence of hormone receptors. This study explored the efficacy of Tulbaghia violacea, a South African medicinal plant, for the treatment of TNBC metastasis. Extracts from T. violacea leaves were prepared using water and methanol. However, only the water-soluble extract showed anti-cancer activity and the effects of this water-soluble extract on cell adhesion, invasion, and migration, and its antioxidant activity were assessed using MCF-10A and MDA-MB-231 cells. The T. violacea extract that was soluble in water effectively decreased the movement and penetration of MDA-MB-231 cells through the basement membrane in scratch and invasion tests, while enhancing their attachment to a substance resembling an extracellular matrix. The sample showed mild-to-low antioxidant activity in the antioxidant assy. Nuclear magnetic resonance spectroscopy revealed 61 chemical components in the water-soluble extract, including DDMP, 1,2,4-triazine-3,5(2H,4H)-dione, vanillin, schisandrin, taurolidine, and α-pinene, which are known to have anti-cancer properties. An in-depth examination of the transcriptome showed alterations in genes linked to angiogenesis, metastasis, and proliferation post-treatment, with reduced activity in growth receptor signaling, angiogenesis, and cancer-related pathways, such as the Wnt, Notch, and PI3K pathways. These results indicate that T. violacea may be a beneficial source of lead chemicals for the development of potential therapeutic medicines that target TNBC metastasis. Additional studies are required to identify the precise bioactive chemical components responsible for the observed anti-cancer effects.

2.
Cancer Sci ; 115(4): 1317-1332, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279512

RESUMO

T-cell acute leukemia and lymphoma have a poor prognosis. Although new therapeutic agents have been developed, their therapeutic effects are suboptimal. α-Pinene, a monoterpene compound, has an antitumor effect on solid tumors; however, few comprehensive investigations have been conducted on its impact on hematologic malignancies. This report provides a comprehensive analysis of the potential benefits of using α-pinene as an antitumor agent for the treatment of T-cell tumors. We found that α-pinene inhibited the proliferation of hematologic malignancies, especially in T-cell tumor cell lines EL-4 and Molt-4, induced mitochondrial dysfunction and reactive oxygen species accumulation, and inhibited NF-κB p65 translocation into the nucleus, leading to robust apoptosis in EL-4 cells. Collectively, these findings suggest that α-pinene has potential as a therapeutic agent for T-cell malignancies, and further investigation is warranted.


Assuntos
Monoterpenos Bicíclicos , Neoplasias Hematológicas , Neoplasias , Humanos , NF-kappa B/metabolismo , Linfócitos T/metabolismo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células
3.
Chemphyschem ; 25(6): e202300891, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38265929

RESUMO

The absolute photoionization cross section of the monoterpenoid, alpha-pinene (AP), is presented together with the relative photoionization cross sections of its dissociative fragments for the first time. Experiments are performed via multiplexed vacuum ultraviolet (VUV) synchrotron photoionization (PI) mass spectrometry in the 8.0-11.0 eV energy range. Experimental work is conducted at the Advanced Light Source of the Lawrence Berkeley National Laboratory. Dissociative fragments were identified at m/z 121, 94, 93, 92, and 80. The photoionization cross section for the parent mass at 11.0 eV was determined to be 17±4 Mb with a total ionization cross section of 92±23 Mb at the same photon energy. Experimental appearance energies of dissociative ionization fragments and potential dissociative ionization pathways calculated at the G4 level of theory are presented as well.

4.
Environ Sci Technol ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39255966

RESUMO

Secondary organic aerosol (SOA) comprises the majority of submicron particles and is important for air pollution, health, and climate. When SOA mixes with inorganic particles containing transition metals (e.g., Fe), chemical reactions altering physicochemical properties can occur. Here, we study Fe's impact on the formation and chemical composition of SOA formed via dark α-pinene ozonolysis on either (NH4)2SO4 or Fe-containing (NH4)2SO4 seed particles and aged at varying relative humidities (RHs). Aerosol composition was determined using online extractive electrospray ionization mass spectrometry, providing high-resolution chemical and temporal identification of monomers and dimers in the SOA. At high RH, Fe's presence resulted in higher particulate SOA mass concentrations (117 ± 14 µg m-3) than those formed in its absence (70 ± 1 µg m-3). Enhanced mass is coupled with more dimers (C15-20's), attributed to Fenton-driven oligomerization reactions. Experiments with Fe3+-containing seeds showed similar chemical composition and enhanced SOA mass, suggesting a dark reduction pathway to form Fe2+ in the presence of SOA. Overall, Fe's presence at high RH lowers SOA volatility and enhances particulate organic mass and condensed phased reactions of higher volatility species that would normally not participate in SOA formation, which may be important when considering its formation in air quality and climate models.

5.
Macromol Rapid Commun ; 45(3): e2300524, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37903330

RESUMO

Polyamides (PA) are among the most essential and versatile polymers due to their outstanding characteristics, for example, high chemical resistance and temperature stability. Furthermore, nature-derived monomers can introduce hard-to-synthesize structures into the PAs for unique polymer properties. Pinene, as one of the most abundant terpenes in nature and its presumable stability-giving bicyclic structure, is therefore highly promising. This work presents simple anionic ring-opening polymerizations of ß-pinene lactam (AROP) in-bulk and in solution. PAs with high molecular weights, suitable for further processing, are produced. Their good mechanical, thermal (Td s up to 440 °C), and transparent appearance render them promising high-performance biomaterials. In the following, the suitability of different initiators is discussed. Thereby, it is found that NaH is the most successful for in-bulk polymerization, with a degree of polymerization (DP) of about 322. For solution-AROP, iPrMgCl·LiCl is successfully used for the first time, achieving DPs up to about 163. The obtained PAs are also hot-pressed, and the dynamic mechanical properties are analyzed.


Assuntos
Monoterpenos Bicíclicos , Lactamas , beta-Lactamas , Lactamas/química , Nylons/química , Peso Molecular , Polímeros/química , Florestas , Polimerização
6.
Chirality ; 36(8): e23702, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39138008

RESUMO

Pistacia palaestina Boiss. is a common tree in the Mediterranean maquis. The leaves of this plant accumulate defensive monoterpenes, whose levels greatly increase in galls induced by the aphid Baizongia pistaciae. We previously found a significant chemopolymorphism in monoterpene content among individual trees, but the chirality of these monoterpenes was unknown. Although most plant species specifically accumulate one enantiomeric form of a given compound, P. palaestina individuals display chemopolymorphism in the chirality of the key monoterpenes accumulated. We report here a marked enantiomeric variation for the limonene, α- and ß-pinene, camphene, sabinene, δ-3-carene, and terpene-4-ol content in leaves and galls of nine different naturally growing P. palaestina trees. Interestingly, insect-induced gall monoterpene composition is an augmentation of the specific enantiopolymorphism originally displayed by each individual tree.


Assuntos
Monoterpenos , Pistacia , Folhas de Planta , Folhas de Planta/química , Monoterpenos/química , Pistacia/química , Estereoisomerismo , Animais , Afídeos , Tumores de Planta/parasitologia
7.
Int J Mol Sci ; 25(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38279251

RESUMO

Glucose transporter-4 (GLUT4) represents the major glucose transporter isoform responsible for glucose uptake into insulin-sensitive cells, primarily in skeletal muscle and adipose tissues. In insulin-resistant conditions, such as type 2 diabetes mellitus, GLUT4 expression and/or translocation to the cell plasma membrane is reduced, compromising cell energy metabolism. Therefore, the use of synthetic or naturally occurring molecules able to stimulate GLUT4 expression represents a good tool for alternative treatments of insulin resistance. The present study aimed to investigate the effects of essential oils (EOs) derived from Pinus spp. (P. nigra and P. radiata) and of their main terpenoid constituents (α- and ß-pinene) on the expression/translocation of GLUT4 in myoblast C2C12 murine cells. For this purpose, the chemical profiles of the EOs were first analyzed through gas chromatography-mass spectrometry (GC-MS). Cell viability was assessed by MTT assay, and GLUT4 expression/translocation was evaluated through RT-qPCR and flow cytometry analyses. The results showed that only the P. nigra essential oil (PnEO) and α-pinene can increase the transcription of the Glut4/Scl2a4 gene, resulting in a subsequent increase in the amount of GLUT4 produced and its plasma membrane localization. Moreover, the PnEO or α-pinene can induce Glut4 expression both during myogenesis and in myotubes. In summary, the PnEO and α-pinene emulate insulin's effect on the GLUT4 transporter expression and its translocation to the muscle cell surface.


Assuntos
Monoterpenos Bicíclicos , Diabetes Mellitus Tipo 2 , Óleos Voláteis , Camundongos , Animais , Insulina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Óleos Voláteis/farmacologia , Óleos Voláteis/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Insulina Regular Humana/farmacologia , Glucose/metabolismo
8.
Molecules ; 29(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611858

RESUMO

Nowadays, the effective processing of natural monoterpenes that constitute renewable biomass found in post-production waste into products that are starting materials for the synthesis of valuable compounds is a way to ensure independence from non-renewable fossil fuels and can contribute to reducing global carbon dioxide emissions. The presented research aims to determine, based on DFT calculations, the activity and reactivity of limonene, an organic substrate used in previous preparative analyses, in comparison to selected monoterpenes such as cymene, pinene, thymol, and menthol. The influence of the solvent model was also checked, and the bonds most susceptible to reaction were determined in the examined compounds. With regard to EHOMO, it was found that limonene reacts more easily than cymene or menthol but with more difficultly than thymol and pienene. The analysis of the global chemical reactivity descriptors "locates" the reactivity of limonene in the middle of the studied monoterpenes. It was observed that, among the tested compounds, the most reactive compound is thymol, while the least reactive is menthol. The demonstrated results can be a reference point for experimental work carried out using the discussed compounds, to focus research on those with the highest reactivity.

9.
Molecules ; 29(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257382

RESUMO

Schinus terebinthifolius Raddi, popularly known as "Pink pepper", is a plant native to Brazil. The objective of this work was to analyze the chemical composition and the antioxidant and antibacterial potential of essential oils (EOs) from the leaves, fruits and twigs of S. terebinthifolius, aiming for their application in food safety. EOs were obtained by hydrodistillation and the chemical composition was determined by gas chromatography coupled to mass spectrometry. Phenolic compounds were quantified and antioxidant activity was evaluated using three different methods. The antibacterial activity was determined by the broth microdilution method against foodborne bacteria. In the chemical analysis, 22 compounds were identified in the leaves, 13 compounds in the fruits and 37 compounds in the twigs, revealing the presence of the main compounds germacrene D (12.04%, 15.78%, 20,41%), caryophyllene (15.97%, 3.12%, 11.73%), α-pinene (11.6%, 17.16%, 2.99%), ß-pinene (5.68%, 43.34%, 5.60%) and γ-gurjunene (16,85%, 3,15%) respectively. EOs showed better antioxidant potential using the ß-carotene/linoleic acid method with 40.74, 61.52 and 63.65% oxidation inhibition for leaves, fruits and twigs, respectively. The EO from the leaves showed greater antibacterial potential against Escherichia coli and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 0.62 mg mL-1, a value lower than the MIC of sodium nitrite (5.00 mg mL-1), the antimicrobial standard synthetic. The activities of pink pepper EOs suggest their potential as a biopreservative in foods.


Assuntos
Óleos Voláteis , Piper nigrum , Frutas , Antioxidantes/farmacologia , Schinus , Óleos Voláteis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia , Escherichia coli
10.
Chemistry ; 29(16): e202203656, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36445818

RESUMO

Herein, we report the design and scalable synthesis of three new Co(III) complexes, which have an unusual hydrocarbon η1 -alkyl-η3 -allyl-η5 -cyclopentadienyl ligation structure, from the reactions of readily available cobalt(II) compound CoCl2 (PPh3 )2 and biomass material ß-pinene via C-C bond activation. These Co(III) complexes are air-stable, fairly volatile, and thermally stable, so they are excellent candidates as the metal precursors for the vapor deposition of cobalt-containing thin films. As a demonstration, we show that the Co(III) complex of [(3'-5'-η,1-σ)-methylene(2,2,4-trimethyl-4-cyclohexene-1,3-diyl)](η5 -methylcyclopentadienyl)Co (i. e. (seco-pinene)(MeCp)Co) is well suited for the atomic layer deposition (ALD) of Co3 O4 and CoS2 thin films, and the deposited Co3 O4 and CoS2 films are able to conformally cover trench structures with a fairly high aspect ratio of 10 : 1.

11.
Neurochem Res ; 48(6): 1775-1782, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36689085

RESUMO

Huntington's disease (HD) is a progressive, neurodegenerative, and inherited disease. Antioxidants have been shown to be effective in slowing disease progression in animal models of HD and are under investigation in human clinical trials. α-pinene, a member of the monoterpene class, has been shown to exert antioxidant activity. Therefore, this study aimed to investigate the impact of α-pinene on animal model of HD. Thirty-two male Wistar rats received 3-Nitropropionic acid (3-NP) for induction of the disease model or treated with α-pinene + 3-NP in different groups. Motor skill, and biochemical evaluations to detect oxidant/antioxidant markers in rat cortex and striatum were performed in all groups. We found that α-pinene significantly improved 3-NP-induced changes in the body weight, rotarod activity, time taken to cross the narrow beam, and locomotor activity. Biochemical analysis revealed that α-pinene significantly decreased the 3NP-induced elevation in oxidant markers, nitrite, and malondialdehyde in both cortex and striatum. In addition, α-pinene counteracted the 3-NP-induced fall in antioxidant enzymes, including superoxide dismutase, catalase, and glutathione in the cortex and striatum. In conclusion, we found that α-pinene prevented the motor dysfunction induced by 3-NP in the animal model of Huntington's disease. Oxidants-antioxidant balance might be involved in the protective effect of α-pinene.


Assuntos
Doença de Huntington , Fármacos Neuroprotetores , Humanos , Ratos , Masculino , Animais , Antioxidantes/farmacologia , Ratos Wistar , Doença de Huntington/induzido quimicamente , Doença de Huntington/tratamento farmacológico , Atividade Motora , Peroxidação de Lipídeos , Modelos Animais , Oxidantes , Nitrocompostos/farmacologia , Modelos Animais de Doenças , Fármacos Neuroprotetores/uso terapêutico , Comportamento Animal
12.
Mol Biol Rep ; 50(10): 8615-8622, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37648947

RESUMO

BACKGROUND: Alpha-pinene (α-pinene) is a monoterpene with gastroprotective activity. We evaluated the gastroprotective effect of α-pinene in the gastric damage model with ethanol. METHODS: We evaluated the macroscopic evaluation of the stomach cavity, alteration in pH, mRNA expression of nuclear factor erythroid 2- related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), total antioxidant capacity (TAC) levels, and histopathological changes. RESULTS: Pretreatment with α-pinene (10, 50 and 100 mg/kg i.p.) before oral administration of ethanol reduced gastric mucosal damage by increasing the percentage of ulcer inhibition. Alpha-pinene also increased gastric pH similar to omeprazole. In addition, the histopathological examination showed that in the groups pretreated with α-pinene 50 and 100 mg/kg, and omeprazole20 mg/kg, the lesions were less than the control group. Moreover, α- pinene 10, 50, 100, and omeprazole 20 mg/kg upregulated the NRF2 and HO1. CONCLUSIONS: Our results show that pretreatment with α-pinene is effective in reducing ethanol-induced gastric damage through regulation of Nrf2/HO-1.


Assuntos
Heme Oxigenase-1 , Fator 2 Relacionado a NF-E2 , Animais , Ratos , Heme Oxigenase-1/genética , Estômago , Transdução de Sinais , Etanol , Omeprazol/farmacologia
13.
Mol Biol Rep ; 50(8): 6505-6516, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37329479

RESUMO

BACKGROUNDS: Cerebral ischemia-reperfusion leads to brain tissue injury. Inflammation and apoptosis play pivotal roles in the pathology. OBJECTIVE: α-Pinene is an organic compound of many aromatic plants and is known as a potent agent to possess antioxidant, and anti-inflammatory properties. Here, we sought to identify the anti-inflammatory and anti-apoptosis mechanism by which α-Pinene improves brain ischemia injury. RESULTS: Male Wistar rats underwent MCAO surgery for 1 h and different doses of alpha-pinene (25, 50, and 100 mg/kg) were intraperitoneally injected immediately after reperfusion to test this hypothesis. IV, NDS, gene and protein expression of inducible nitric oxide synthase (iNOS), cyclogenase-2 (COX-2), nuclear factor kappa B (NF-κB) p65, and caspase-3 were assessed 24 h after reperfusion. Results demonstrated that NF-κB p65, iNOS, and COX-2 gene and protein expression increased in the hippocampus, cortex, and striatum after 24 h of reperfusion, and alpha-pinene significantly inhibited NF-kB p65, iNOS, and COX-2 expression. Also, alpha-pinene significantly reduced the ischemia/reperfusion-induced caspase-3 activation in CA1 area of hippocampus. CONCLUSION: Results showed that alpha-pinene protects the cerebral against ischemic damage caused by MCAO, and this effect may be through the regulating iNOS -NF-kappa B- COX-2 and caspase-3 inflammatory and apoptotic pathways.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Ratos , Animais , NF-kappa B/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos Wistar , Isquemia Encefálica/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Óxido Nítrico/metabolismo
14.
Biotechnol Appl Biochem ; 70(1): 403-414, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35638476

RESUMO

Pinene is a commercially important monoterpene that can be prepared using engineered bacterial and yeast species; however, high pinene levels can adversely affect the stability and permeability of microbial membranes leading to significantly reduced growth yields. This study reports that the fluidities and permeabilities of cell membranes of Candida glycerinogenes decrease as pinene levels increase resulting in adverse effects on cell growth. Exposure of cells to pinene results in upregulation of the genes encoding ergosterol and trehalose whose production helps stabilize their cell membranes. Exogenous addition of ergosterol and trehalose to pinene-treated cells also reduces the fluidity and permeability of the cell membrane, whilst also reducing production of intracellular reactive oxygen species. This led to the finding that the biomass of yeast cells cultivated in shake flask systems are improved by exogenous addition of trehalose and ergosterol. Overexpression of genes that encode trehalose and ergosterol produced a recombinant C. glycerinogenes strain that was found to tolerate higher concentrations of  pinene.


Assuntos
Ergosterol , Trealose , Trealose/farmacologia , Trealose/metabolismo , Ergosterol/metabolismo , Membrana Celular , Pichia/metabolismo
15.
Chem Biodivers ; 20(12): e202301302, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37906119

RESUMO

Ferulago bernardii Tomk & M. Pimen belongs to Apiaceae family. Various species of the Ferulago genus have antioxidant, anticholinesterase, cytotoxic, and antiproliferative effects. In this study, the essential oil of F. bernardii was extracted using the Clevenger apparatus. The essential oil compounds were identified using GC-MS/FID. The interaction between the essential oil and DNA strands was evaluated through spectrophotometric titration. The molecular mechanism of the interaction between the main components of the essential oil and different DNA strands was assessed using molecular dynamics simulation. Based on the results, 92.03±1.20 % of the essential oil consisted of α-pinene. Therefore, the essential oil could serve as a suitable source of α-pinene. α-pinene is a monoterpene hydrocarbon that has various effects, including anti-inflammatory, antioxidant, antimicrobial, and antitumor properties. The binding constant of the essential oil to DNA strands (Ka ) was determined to be 5.40±0.47×10-3  M-1 . Molecular dynamics simulation demonstrated that α-pinene could interact with AT and CG rich DNA strands and indirectly stabilize G-Quadruplex. Given the different applications for α-pinene and its high percentage in the essential oil, it is suggested that researchers pay more attention to F. bernardii in the pharmaceutical, cosmetic, and food industries.


Assuntos
Apiaceae , Óleos Voláteis , Antioxidantes/farmacologia , Antioxidantes/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Apiaceae/química , DNA
16.
Bioprocess Biosyst Eng ; 46(9): 1331-1340, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37470869

RESUMO

Chemoenzymatic epoxidation of olefin mediated by lipase is a green and environmentally friendly alternative process. However, the mass transfer barrier and lipase deactivation caused by the traditional organic-water biphasic reaction system have always been the focus of researchers' attention. To overcome these issues, we investigated the effects of reaction temperature and two important substrates (H2O2 and acyl donor) on the epoxidation reaction and interfacial mass transfer. As a result, we determined the optimal reaction conditions: a temperature of 30 °C, 30 wt-% H2O2 as the oxygen source, and 1 M lauric acid as the oxygen carrier. Additionally, by simulating the conditions of shaking flask reactions, we designed a batch reactor and added a metal mesh to effectively block the direct contact between high-concentration hydrogen peroxide and the enzyme. Under these optimal conditions, the epoxidation reaction was carried out for 5 h, and the product yield reached a maximum of 93.2%. Furthermore, after seven repetitive experiments, the lipase still maintained a relative activity of 51.2%.


Assuntos
Peróxido de Hidrogênio , Lipase , Monoterpenos Bicíclicos , Alcenos
17.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36982225

RESUMO

Previous studies on biocatalytic transformations of pinenes by cytochrome P450 (CYP) enzymes reveal the formation of different oxygenated products from a single substrate due to the multistate reactivity of CYP and the many reactive sites in the pinene scaffold. Up until now, the detailed mechanism of these biocatalytic transformations of pinenes have not been reported. Hereby, we report a systematic theoretical study of the plausible hydrogen abstraction and hydroxylation reactions of α- and ß-pinenes by CYP using the density functional theory (DFT) method. All DFT calculations in this study were based on B3LYP/LAN computational methodology using the Gaussian09 software. We used the B3LYP functional with corrections for dispersive forces, BSSE, and anharmonicity to study the mechanism and thermodynamic properties of these reactions using a bare model (without CYP) and a pinene-CYP model. According to the potential energy surface and Boltzmann distribution for radical conformers, the major reaction products of CYP-catalyzed hydrogen abstraction from ß-pinene are the doublet trans (53.4%) and doublet cis (46.1%) radical conformer at delta site. The formation of doublet cis/trans hydroxylated products released a total Gibbs free energy of about 48 kcal/mol. As for alpha pinene, the most stable radicals were trans-doublet (86.4%) and cis-doublet (13.6%) at epsilon sites, and their hydroxylation products released a total of ~50 kcal/mol Gibbs free energy. Our results highlight the likely C-H abstraction and oxygen rebounding sites accounting for the multi-state of CYP (doublet, quartet, and sextet spin states) and the formation of different conformers due to the presence of cis/trans allylic hydrogen in α-pinene and ß-pinene molecules.


Assuntos
Sistema Enzimático do Citocromo P-450 , Modelos Teóricos , Hidroxilação , Sistema Enzimático do Citocromo P-450/metabolismo , Hidrogênio
18.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36982242

RESUMO

Polymers based on renewable monomers are projected to have a significant role in the sustainable economy, even in the near future. Undoubtedly, the cationically polymerizable ß-pinene, available in considerable quantities, is one of the most promising bio-based monomers for such purposes. In the course of our systematic investigations related to the catalytic activity of TiCl4 on the cationic polymerization of this natural olefin, it was found that the 2-chloro-2,4,4-trimethylpentane (TMPCl)/TiCl4/N,N,N',N'-tetramethylethylenediamine (TMEDA) initiating system induced efficient polymerization in dichloromethane (DCM)/hexane (Hx) mixture at both -78 °C and room temperature. At -78 °C, 100% monomer conversion was observed within 40 min, resulting in poly(ß-pinene) with relatively high Mn (5500 g/mol). The molecular weight distributions (MWD) were uniformly shifted towards higher molecular weights (MW) in these polymerizations as long as monomer was present in the reaction mixture. However, chain-chain coupling took place after reaching 100% conversion, i.e., under monomer-starved conditions, resulting in considerable molecular weight increase and MWD broadening at -78 °C. At room temperature, the polymerization rate was lower, but chain coupling did not occur. The addition of a second feed of monomer in the polymerization system led to increasing conversion and polymers with higher MWs at both temperatures. 1H NMR spectra of the formed polymers indicated high in-chain double-bond contents. To overcome the polarity decrease by raising the temperature, polymerizations were also carried out in pure DCM at room temperature and at -20 °C. In both cases, rapid polymerization occurred with nearly quantitative yields, leading to poly(ß-pinene)s with Mns in the range of 2000 g/mol. Strikingly, polymerization by TiCl4 alone, i.e., without any additive, also occurred with near complete conversion at room temperature within a few minutes, attributed to initiation by adventitious protic impurities. These results convincingly prove that highly efficient carbocationic polymerization of the renewable ß-pinene can be accomplished with TiCl4 as catalyst under both cryogenic conditions, applied widely for carbocationic polymerizations, and the environmentally benign, energy-saving room temperature, i.e., without any additive and cooling or heating. These findings enable TiCl4-catalyzed eco-friendly manufacturing of poly(ß-pinene)s, which can be utilized in various applications, and in addition, subsequent derivatizations could result in a range of high-added-value products.


Assuntos
Alcenos , Polímeros , Temperatura , Polimerização , Polímeros/química , Catálise
19.
Molecules ; 28(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36985605

RESUMO

The essential oils (EOs) of Guatteria schomburgkiana (Gsch) and Xylopia frutescens (Xfru) (Annonaceae) were obtained by hydrodistillation, and their chemical composition was evaluated by gas chromatography-mass spectrometry (GC/MS). Herbicide activity was measured by analyzing the seed germination percentage and root and hypocotyl elongation of two invasive species: Mimosa pudica and Senna obtusifolia. The highest yield was obtained for the EO of Xfru (1.06%). The chemical composition of Gsch was characterized by the presence of the oxygenated sesquiterpenes spathulenol (22.40%) and caryophyllene oxide (14.70%). Regarding the EO of Xfru, the hydrocarbon monoterpenes α-pinene (35.73%) and ß-pinene (18.90%) were the components identified with the highest concentrations. The germination of seeds of S. obtusifolia (13.33 ± 5.77%) showed higher resistance than that of seeds of M. pudica (86.67 ± 5.77%). S. obtusifolia was also more sensitive to the EO of Xfru in terms of radicle (55.22 ± 2.72%) and hypocotyl (71.12 ± 3.80%) elongation, while M. pudica showed greater sensitivity to the EO of Gsch. To screen the herbicidal activity, the molecular docking study of the major and potent compounds was performed against 4-hydroxyphenylpyruvate dioxygenase (HPPD) protein. Results showed good binding affinities and attributed the strongest inhibitory activity to δ-cadinene for the target protein. This work contributes to the study of the herbicidal properties of the EOs of species of Annonaceae from the Amazon region.


Assuntos
Annonaceae , Guatteria , Óleos Voláteis , Xylopia , Annonaceae/química , Xylopia/química , Guatteria/química , Óleos Voláteis/química , Brasil , Simulação de Acoplamento Molecular , Folhas de Planta/química
20.
Molecules ; 28(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36677644

RESUMO

Nowadays, the demand for rosemary essential oils (REOs) in the cosmetic, food, and pharmaceutical industries is increasing, and the abundant germplasm resources of rosemary provide more possibilities for functional applications. The REOs from six cultivars were selected to evaluate and compare their bioactivities. REOs have good cellular antioxidant activity in scavenging reactive oxygen species, and the technology for order preference by similarity to an ideal solution (TOPSIS)-random forest multivariate model indicated that 'Dutch Mill' REO has the best antioxidant activity, which is closely related to its verbenone content. In addition, α-pinene-dominant REOs are more toxic to human keratinocytes, which is closely related to the content of α-pinene, as revealed by multivariate analyses. Moreover, anti-proliferative assays on six cancer cell lines showed that all REOs have a higher anti-proliferative ability against human pancreatic cancer cell line SW1990 and gastric epithelial cell line NCI-N87. Among them, 'Miss Jessopp's Upright' and 'Blue Lagoon' REOs exhibit more prominent anti-proliferative activity. Our study provides a reference value for exploring the application potential of different REOs by evaluating their differences in chemical composition and bioactivity.


Assuntos
Óleos Voláteis , Rosmarinus , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Rosmarinus/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Compostos Fitoquímicos/farmacologia , Queratinócitos
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