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Medicinas Complementárias
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1.
J Nat Prod ; 87(4): 652-663, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38359463

RESUMEN

Castanea sativa wood is a rich source of hydrolyzable tannins, known for their diverse bioactivities. To investigate these bioactive properties further, it is crucial to isolate and characterize hydrophilic compounds effectively. To address this issue, we developed a centrifugal partition chromatography (CPC) method and applied it to an aqueous C. sativa wood extract. We determined the partition coefficients (KD) of the six major compounds using four butanol-/water-based biphasic solvent systems. Initially, we utilized the n-butanol/propanol/water (3:1:4, v/v/v) systems for the first fractionation step. Subsequently, we employed the water/methyl tert-butyl ether/butanol/acetone (8:5:3:4, v/v/v/v) system to fractionate moderately and highly hydrophilic fractions. We calculated the KD values for major compounds of the most hydrophilic fractions using the butanol/ethanol/water (4:1:5, v/v/v) and butanol/isopropanol/water (2:1:3, v/v/v) systems. In total, we isolated 23 compounds through a combination of CPC, size exclusion chromatography, and preparative HPLC. Among these compounds, six have never been previously described. We characterized them by 1D and 2D NMR experiments and high-resolution mass spectroscopy acquisitions.


Asunto(s)
Fagaceae , Taninos Hidrolizables , Taninos Hidrolizables/química , Taninos Hidrolizables/aislamiento & purificación , Fagaceae/química , Estructura Molecular , Madera/química , Extractos Vegetales/química
2.
Fitoterapia ; 173: 105824, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244895

RESUMEN

Two new 2-(2-phenylethyl)chromones (1-2), two new sesquiterpenes (12-13), and twelve known compounds (3-11, 14-16) were isolated from agarwood of Aquilaria sinensis. These structures were confirmed by HRESIMS, 1D and 2D NMR spectra. The absolute configurations of two new sesquiterpenes were determined by comparing the experimental and calculated ECD spectra. Among them, 7,8-dihydroxy-2-[2-(4'-methoxyphenyl)ethyl]chromone (2) was the first time found that the hydroxyl groups at both C-7/C-8 in agarwood. And Aseudesm B (13), the aldehyded methyl group at C-5 of eucalyptane sesquiterpenes was first discovered in natural products. In the bioassays, all compounds were evaluated for their inhibitory activity against lipopolysaccharide-activated nitric oxide (NO) production in RAW264.7 cells. Compounds 2-5, 7, 9-10, and 13-14 revealed notable inhibitory effects against NO production with IC50 values ranging from 4.0 to 13.0 µM.


Asunto(s)
Sesquiterpenos , Thymelaeaceae , Cromonas/farmacología , Estructura Molecular , Flavonoides/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Thymelaeaceae/química , Sesquiterpenos/química , Óxido Nítrico , Madera/química
3.
Carbohydr Polym ; 326: 121611, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142095

RESUMEN

Hemicellulose and pectin are noteworthy components of historical European rag papers, and have not been studied in detail so far. Rag papers were made from used textiles, and fiber-based utilities, such as ropes and bags. These had been prepared until the mid-19th century from plant-based fibers. Their polysaccharide composition could relate to their condition and history. This information can be expected to hold importance for the preservation and conservation of historical objects. We investigated a collection of rag papers of different age for their composition of non-cellulosic polysaccharides, and compared the findings with modern rag papers and wood pulps. Furthermore, a non-destructive determination of the hemicellulose and pectin content by near-infrared spectroscopy was developed. Historical rag papers had a lower hemicellulose/pectin content than pulps; the fractions of rhamnose, galactose, and arabinose were higher, while xylose was lower. In modern rag papers, xylose tended to be at the higher end of the range, which suggests a degradation of hemicelluloses/pectin over time or a change in raw materials and manufacturing. Rag papers also showed higher crystallinity than wood pulp papers. These findings provide insights into rag paper characteristics and offer potential classification methods.


Asunto(s)
Polisacáridos , Xilosa , Xilosa/metabolismo , Polisacáridos/química , Pectinas/metabolismo , Madera/química , Arabinosa/análisis
4.
Sci Rep ; 13(1): 21929, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-38081973

RESUMEN

This study aimed to evaluate and compare the effects of oil- and air-heat treatments on the durability of Paulownia tomentosa and Pinus koraiensis woods against Fomitopsis palustris and Trametes versicolor. The wood samples were treated in palm oil and air at 180, 200, and 220 °C for 2 h. The weight loss, morphology, crystalline properties, and chemical compounds of untreated and heat-treated wood after fungal attack were investigated. The significant difference in weight loss between oil- and air-heat-treated samples was shown at 220 °C. Heat-treated wood exposed to white-rot fungus showed a lower weight loss than that exposed to brown-rot fungus. The cell components in the untreated- and heat-treated Paulownia tomentosa and Pinus koraiensis at 180 °C were severely damaged due to fungal exposure compared to those at 220 °C. A fungal effect on the relative crystallinity was observed in heat-treated wood at 180 °C, whereas the effect was not observed at 220 °C. Following brown-rot fungus exposure, untreated- and heat-treated wood at 180 °C showed a notable change in the Fourier transform infrared (FTIR) peaks of polysaccharides, whereas no noticeable change in lignin peaks was observed. Heat-treated wood at 220 °C showed no noticeable change in the FTIR spectra owing to brown-rot fungus exposure. Exposure to white-rot fungus did not noticeably change the FTIR spectra of untreated and heat-treated wood.


Asunto(s)
Calor , Magnoliopsida , Pinus , Enfermedades de las Plantas , Madera , Hongos , Lignina/análisis , Aceite de Palma , Pinus/microbiología , Trametes , Pérdida de Peso , Madera/química , Madera/microbiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Magnoliopsida/microbiología , Aire
5.
Environ Res ; 236(Pt 1): 116714, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37482125

RESUMEN

Accurately measuring particulate matter emissions from biomass combustion is crucial for evaluating the performance of fuels, combustion appliances and flue gas cleaning methods. These measurements are essential for refining emission inventories for health risk assessments and environmental models and for defining pollution control strategies. However, as air quality standards become increasingly stringent and emission levels decrease, it is important to develop reliable, accurate measurement methods. This study presents a comprehensive evaluation of two particulate dilution systems, namely a full flow dilution (FFD) tunnel and a two-stage partial flow dilution system (porous tube diluter combined with ejector diluter, PTD + ED), for characterising the particle number size distribution from a wood pellet boiler. The maximum relative sampling errors due to not sampling isokinetically increase with particle size and dilution ratio (DR), but are less than 1% for particles smaller than 1 µm for both systems. The total particle number concentration with FFD is on average 35% lower than with PTD + ED, which suggests substantial particle loss during FFD. In addition with FFD, a strong negative correlation is observed between DR and the average particle size. On the other hand with PTD + ED, both the dilution air temperature and DR have no substantial influence on the particle number emissions. However, it is observed with both systems that the particle distribution is affected by coagulation, and this effect becomes more pronounced as dilution decreases. Overall, this work provides insights into the strengths and limitations of particulate dilution systems for accurately measuring emissions from biomass combustion, which can support the development of more reliable measurement methods and assist in implementing effective pollution control strategies.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , Biomasa , Contaminación del Aire/análisis , Tamaño de la Partícula , Carbón Mineral , Polvo , Madera/química
6.
Fitoterapia ; 169: 105564, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37295754

RESUMEN

Eight previously unknown 2-(2-phenylethyl)chromone derivatives, called aquichromones A - E (1-3, 5 and 6) and 8-epi-aquichromone C (4), including two pairs of enantiomers [(±)-1 and (±)-2] were isolated from the agarwood of Aquilaria sinensis. The structures and absolute stereochemistry of these natural products were elucidated by using spectroscopic and computational methods. The result of biological assay showed that two members of this group, 4 and 5, have significant dose-dependent anti-inflammatory activity.


Asunto(s)
Cromonas , Thymelaeaceae , Cromonas/farmacología , Estructura Molecular , Flavonoides/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Thymelaeaceae/química , Madera/química
7.
Chem Biodivers ; 20(5): e202200931, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37017495

RESUMEN

European plum tree (Prunus domestica L.) is cultivated in many countries for its delicious and nutritive fruit and, accordingly, certain amounts of wood (from pruning works) are generated every year. The main objective of this work was to value this agricultural woody residue, for which the chemical composition of pruning wood extracts from four European plum cultivars was investigated, and the human lactate dehydrogenase A (hLDHA) inhibitory activity of plum wood extracts and pure proanthocyanidins present in those extracts was measured. For the chemical characterization, total phenolic content and DPPH radical-scavenging assays and HPLC-DAD/ESI-MS analyses were performed, the procyanidin (-)-ent-epicatechin-(2α→O→7,4α→8)-catechin (4), the phenolic glucoside (-)-annphenone (3) and the flavan-3-ol catechin (1) being the major components of the wood extracts. Some quantitative and qualitative differences were found among plum cultivars, and the content of proanthocyanidins ranged from 1.51 (cv. 'Claudia de Tolosa') to 8.51 (cv. 'De la Rosa') mg g-1 of dry wood. For the hLDHA inhibitory activity, six wood extracts and six proanthocyanidins were evaluated by a UV spectrophotometric assay, compound 4 showing the highest inhibitory activity (IC50 3.2 µM) of this enzyme involved on the excessive production of oxalate in the liver of patients affected by the rare disease Primary Hyperoxaluria.


Asunto(s)
Catequina , Proantocianidinas , Prunus domestica , Humanos , Prunus domestica/química , Proantocianidinas/farmacología , Catequina/farmacología , Madera/química , Extractos Vegetales/química , Frutas/química
8.
Sci Total Environ ; 884: 163741, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37120025

RESUMEN

Wood-based panels provide efficient alternatives to materials such as plastics derived from traditional petroleum sources and thereby help to mitigate greenhouse gas emissions. Unfortunately, using indoor manufactured panel products also results in significant emissions of volatile organic compounds including olefins, aromatic and ester compounds, which negatively affect human health. This paper highlights recent developments and notable achievements in the field of indoor hazardous air treatment technologies to guide future research toward environmentally friendly and economically feasible directions that may have a significant impact on the improvement of human settlements. Summarizing and synthesizing the principles, advantages, and limitations of different technologies can assist policymakers and engineers in identifying the most appropriate technology for a particular air pollution control program based on criteria such as cost-effectiveness, efficiency, and environmental impact. In addition, insights into the development of indoor air pollution control technologies are provided and potential areas for innovation, improvement of existing technologies, and development of new technologies are identified. Finally, the authors also hope that this sub-paper will raise public awareness of indoor air pollution issues and promote a better understanding of the importance of indoor air pollution control technologies for public health, environmental protection, and sustainable development.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Petróleo , Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Madera/química , Contaminación del Aire Interior/prevención & control , Contaminación del Aire Interior/análisis , Ambiente , Contaminantes Atmosféricos/análisis
9.
Molecules ; 28(4)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36838655

RESUMEN

Agarwood, a highly valuable resin/wood combination with diverse pharmacological activities but scarce supply, has a long history of being used as a medicine in several medical systems. Grafted Kynam agarwood (GKA) has been cultivated successfully recently and has the qualities meeting the definition of premium Kynam agarwood. However, there are few comprehensive comparisons between GKA and normal agarwood in terms of traits, global composition, and activity, and some key issues for GKA to be adopted into the traditional Chinese medical (TCM) system have not been elaborated. The two types of agarwood samples were evaluated in terms of trait characteristics, physicochemical indicators, key component groups, and global compositional profile. Furthermore, a molecular docking was performed to investigate the active ingredients. In vitro activity assays were performed to evaluate the activation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) by GKA and normal agarwood. The results revealed that, overall, the traits, microscopic characteristics, chemical composition types, and bioactivity between GKA and normal agarwood were similar. The main differences were the content of resin (ethanolic extract content), the content of key component groups, and the composition of the different parent structural groups of 2-(2-phenethyl) chromones (PECs). The contents of total PEC and ethanol extract content of GKA were significantly higher than those of normal agarwood. The MS-based high-throughput analysis revealed that GKA has higher concentrations of sesquiterpenes and flindersia-type 2-(2-phenylethyl) chromones (FTPECs) (m/z 250-312) than normal agarwood. Molecular docking revealed that parent structural groups of FTPECs activated multiple signaling pathways, including the AMPK pathway, suggesting that FTPECs are major active components in GKA. The aim of this paper is to describe the intrinsic reasons for GKA as a high-quality agarwood and a potential source for novel drug development. We combined high-throughput mass spectrometry and multivariate statistical analysis to infer the different components of the two types of agarwood. Then we combined virtual screening and in vitro activity to construct a component/pharmacodynamic relationship to explore the causes of the activity differences between agarwood with different levels of quality and to identify potentially valuable lead compounds. This strategy can also be used for the comprehensive study of other TCMs with different qualities.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Thymelaeaceae , Simulación del Acoplamiento Molecular , Thymelaeaceae/química , Cromonas/química , Madera/química , Resinas de Plantas/análisis , Extractos Vegetales/química , Flavonoides/química
10.
Fitoterapia ; 165: 105421, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36587748

RESUMEN

Two rare flavonoid-2-(2-phenylethyl)chromones and five new dimeric 2-(2-phenylethyl)chromones were isolated from ethanol extract of agarwood of Aquilaria walla by LC-MS-guided fractionation procedure. Their structures were established based on extensive spectroscopic methods including HRESIMS, 1D and 2D NMR, as well as by comparison with the literature. Compound 1 showed cytotoxic activity against five human cancer cell lines with IC50 values ranging from 13.40 to 28.96 µM with cisplatin as the positive control.


Asunto(s)
Cromonas , Thymelaeaceae , Humanos , Cromonas/farmacología , Thymelaeaceae/química , Estructura Molecular , Flavonoides/química , Espectrometría de Masas , Madera/química
11.
Environ Sci Pollut Res Int ; 30(1): 773-787, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35904741

RESUMEN

Long-term and high-intensity application of inorganic fertilizer leads to a strong variation of soil characteristics. The changes in soil chemical and biological properties can significantly affect the yield of Eucalyptus plantation. However, the mechanism of soil chemical properties affecting wood volume mediated by biological factors is not clear. The purpose of this study was to identify which soil properties were affected by different fertilization intensities and to disentangle the dominant factors affecting Eucalyptus volume. After clear felling evergreen broad-leaved forest, a Eucalyptus plantation was established that was coppiced every 5 years and fertilized every year. Within this plantation, areas with different treatments were established. These treatments were a 5-year growth period (low); two times 5-year growth period (medium); and three times 5-year growth period (high). In each treatment area and in a nearby evergreen broad-leaved forest (EBLF Control), five sample plots per treatment were set up. Various biological and chemistry analyses (18 in total) were related to determining the most important path and index for optimizing Eucalyptus plantation. The analysis of variance of enzyme activity and microbial biomass showed that the soil biological characteristics decreased over 10 years of plantation, and the enzyme activity was close to the state of EBLF control in medium, while the microbial biomass failed to return to its original state during continuous planting. Redundancy analysis results show that there was a strong correlation in chemical indicators and biological characteristics. Partial least square structural equation model showed that total phosphorus, nitrate nitrogen, urease, catalase, and microbial biomass nitrogen and phosphorus were the most influential soil biochemical factors, and the indirect effect of chemical properties on volume was achieved by microorganisms through enzyme activity. Continuous planting and large-scale application of inorganic fertilizer would lead to a decrease in plantation yield and fertilizer utilization efficiency and would affect the microbial biomass and enzyme activity by destroying the stability of soil chemical properties.


Asunto(s)
Eucalyptus , Suelo , Suelo/química , Madera/química , Fertilizantes/análisis , Microbiología del Suelo , Nitrógeno/análisis , Fósforo/análisis
12.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36555291

RESUMEN

Currently, emphasis is placed on using environmentally friendly materials both from a structural point of view and the application of protective means. For this reason, it is advisable to deal with the thermal modification of wood, which does not require the application of protective substances, to increase its service life. The main reason for the thermal modification of black locust is that although black locust grows abundantly in our country, it has no industrial use. It is mainly used outdoors, where thermal modification could increase its resistance. This article deals with the thermal modification of black locust wood (Robinia pseudoacacia L.) and the impact of this modification on the chemical components of the wood with an overlap in the change in mechanical properties compared to untreated wood. Static (LOP, MOR, and MOE) and dynamic (IBS) bending properties were evaluated as representative mechanical properties. At the same time, the impact of thermal modification on the representation of chemical components of wood (cellulose, lignin, hemicellulose) was also tested. As a result of the heat treatment, the mechanical properties gradually decreased as the temperature increased. The highest decrease in mechanical values found at 210 °C was 43.7% for LOP and 45.1% for MOR. Thermal modification caused a decrease in the content of wood polysaccharides (the decrease in hemicelluloses content was 33.2% and the drop in cellulose was about 29.9% in samples treated at 210 °C), but the relative amount of lignin in the wood subjected to increased temperature was higher due to autocondensation, and mainly because of polysaccharide loss. Based on the correlations between chemical and mechanical changes caused by thermal modification, it is possible to observe the effects of reducing the proportions of chemical components and changes in their characteristic properties (DP, TCI) on the reduction in mechanical properties. The results of this research serve to better understand the behavior of black locust wood during thermal modification, which can primarily be used to increase its application use.


Asunto(s)
Lignina , Robinia , Lignina/análisis , Madera/química , Celulosa/química , Temperatura
13.
Molecules ; 27(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36432077

RESUMEN

The purpose of this study was to characterize and quantify the chemical constituents of heartwood and sapwood of Dalbergia oliveri extract in order to investigate the chemical components that determine the formation of heartwood's color. In this work, the types of pigments in heartwood and sapwood extract were analyzed using UV-Visible (UV) Spectrophotometer, and the main pigment components of heartwood and sapwood extract were identified and quantified using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS). The results showed that the difference in content of the main components between heartwood and sapwood of Dalbergia oliveri was slight, and the lignin structure between heartwood and sapwood is basically identical; flavonoid pigments were found to be the primary chromophoric components of heartwood and sapwood extract. However, a total of 21 flavonoids were identified in heartwood and sapwood, of which the unique substances to heartwood were vitexin, isorhamnetin, and pelargonidin, and the content of isoliquiritigenin, formononetin, and biochanin A were 253, 37, and 583 times higher in the heartwood than in the sapwood, respectively, which could be the main pigment components affecting the significant color difference between heartwood and sapwood of Dalbergia oliveri. These results will provide a foundation for revealing the underlying mechanism of color difference between heartwood and sapwood and provide a theoretical basis for wood coloring.


Asunto(s)
Dalbergia , Madera , Flavonoides/análisis , Lignina/análisis , Extractos Vegetales/análisis , Madera/química
14.
Analyst ; 147(21): 4857-4865, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36149381

RESUMEN

Hongmu, a Chinese customary noun representing 29 kinds of wood species such as some Pterocarpus species (abbreviated as spp. hereinafter), Dalbergia spp. and Diospyros spp., is popular among Chinese people due to the furniture made from it. The slow regeneration of hongmu resources led to a decline in production, making hongmu prices high and illegal businesses profit from it. Therefore, it is necessary to identify and distinguish different varieties of hongmu for commercial trade. Herein, a cost-effective and rapid methodology was first developed via atmospheric pressure glow discharge mass spectrometry (APGD-MS) to classify three Dalbergia spp. and three Pterocarpus spp. Meanwhile, principal component analysis (PCA) was further applied to distinguish wood species and six kinds of hongmu extracts were able to be approximately separated into six units. Besides, hongmu could be clearly distinguished from their counterfeits, such as Guibourtia spp., using the method provided here. This method may provide a timely and necessary way for the determination of ingredients and identification of the authenticity of hongmu.


Asunto(s)
Presión Atmosférica , Dalbergia , Humanos , Espectrometría de Masas/métodos , Madera/química , Extractos Vegetales/análisis
15.
ACS Nano ; 16(8): 13144-13151, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35968966

RESUMEN

Continuous filtering adsorption has drawn growing interest in the exploration of uranium resources in seawater and reduction in the environmental risks of uraniferous wastewater from nuclear industries. For most filtering adsorbents, repeated filtration, high membrane thickness, and high pressure are normally essential to achieve both a high rejection ratio and high filtration flux. Herein cellulose fibrils were preferentially exfoliated from the lignin-poor layer of secondary cell walls of balsa wood during an in situ amidoximation process. By maintaining honeycomb-like cellular microstructures and cellulose aerogel stuffing in their cell tracheids, the resultant nanowoods showed superior mechanical properties (e.g., compressive strength ∼1.3 MPa in transverse direction) with large surface areas (∼80 m2 g-1). When their cell tracheids were aligned perpendicular to the flow and the edges sealed with a thermoset polymer, they could serve as efficient and high-pressure filtration membranes to capture aquatic uranium ions. In analogy to a typical cascading filtration system, the filtrate passed successively the layered-organized cell tracheids through abundant micropores on their cell walls, enabling a high rejection ratio of >99% and flux of ∼920 L m-2 h-1 under pressure up to 6 bar (membrane thickness of 2 mm). Thus, this study not only provides an in situ approach to producing robust woods with functional nanocellulose encapsulated into their cell tracheids but also offers a sustainable route for high-efficiency extraction of aqueous uranium.


Asunto(s)
Nanofibras , Uranio , Madera/química , Nanofibras/química , Adsorción , Uranio/análisis , Uranio/química , Celulosa/química , Iones
16.
Int J Biol Macromol ; 220: 766-774, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35987360

RESUMEN

Polyvinylidene fluoride (PVDF) is commonly used in the chemical, electronic, and petrochemical industries because of its chemical and physical attributes. This study aimed to make novel PVDF-based composite with a high loading of silanized wood powder and micro/nanocellulose fibers, where glycerol acts as both a dispersant and a plasticizer all-in-one composite application for the first time. The purpose was also extended to systematically investigate their mechanical properties and melt flow. Results have demonstrated the efficiency of utilizing the cellulose fibers in bio-composites. With the addition of 30 wt% of filling materials, When the content of silanized cellulose fibers in glycerol dispersion is 25 wt%, the flexural strength and tensile strength reach the maximum value 72.30 MPa and 52.28 MPa. The experimental results indicate that silanized micro/nanocellulose fiber-reinforced PVDF/wood composites are a promising composite formula to help improve performance and reduce costs. It is an excellent example of utilizing biomass resources as a renewable/recyclable, sustainable and low-cost material to reduce the use of petroleum-based polymer, and improve the mechanical properties of composites.


Asunto(s)
Petróleo , Madera , Celulosa/química , Polímeros de Fluorocarbono , Glicerol/análisis , Ensayo de Materiales , Petróleo/análisis , Plastificantes , Polímeros/química , Polivinilos , Polvos , Madera/química
17.
Int J Biol Macromol ; 209(Pt A): 83-92, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35351550

RESUMEN

As a soybean oil extractive byproduct, high temperature defatted soy meal (HSM) presents great potential as a raw material for vegetable protein adhesives to replace aldehyde-based adhesives in the wood-based panel production. However, the application has been hindered by its poor cold-pressing adhesive performance. Herein, a novel HSM-based adhesive with excellent cold-pressing adhesion performance was developed based on mussel-inspired cation-π interactions. Highly reactive polyamidoamine-epichlorohydrin (PAE) and folic acid (FA) were added into an HSM-based adhesive to construct a dual-network system stabilized by strong cation-π interactions. The coacervate formed by PAE and FA served as an "internal adhesive" to bond HSM particles together, yielding high initial viscosity but easy sizing. As expected, the prepared adhesive exhibited an excellent cold-pressing bonding strength of 423 kPa, showing a 295% improvement compared to the soy protein (SP) adhesive. To improve the hot-pressing bonding strength of the adhesives, inorganic calcium carbonate (CaCO3) particles were introduced into the adhesive system to build an organic-inorganic hybrid adhesive system. The wet shear strength of the SPAE-FA-CaCO3 adhesive significantly improved from 0.63 MPa to 0.96 MPa, meeting the requirements for the practical application. This method provides a novel strategy to exploit high-performance vegetable protein-based wood adhesives.


Asunto(s)
Adhesivos , Madera , Adhesivos/química , Cationes , Aceite de Soja , Proteínas de Soja/química , Madera/química
18.
Molecules ; 27(4)2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35209110

RESUMEN

Dalbergia cochinchinensis has been widely used in traditional medicine because of its flavonoids; however, the impact of the flavonoids to modulate the inflammatory response to oral cells remains to be described. For this aim, we isolated 4,7,2'-trihydroxy-4'-methoxyisoflavanol (472T4MIF) and 6,4'-dihydroxy-7-methoxyflavane (64D7MF) from the heartwood of D. cochinchinensis and confirmed the chemical structure by nuclear magnetic resonance. We show here that both flavonoids are inhibitors of an inflammatory response of murine RAW 264.7 inflammatory macrophages stimulated by LPS. This is indicated by interleukin (IL)1, IL6, and chemokine CCL2 production besides the phosphorylation of p65. Consistently, in primary murine macrophages, both flavonoids decreased the inflammatory response by lowering LPS-induced IL1 and IL6 expression. To introduce oral cells, we have used human gingival fibroblasts and provoked the inflammatory response by exposing them to IL1ß and TNFα. Under these conditions, 472T4MIF, but not 64D7MF, reduced the expression of chemokines CXCL1 and CXCL2. Taken together, we identified two flavonoids that can reduce the expression of cytokines and chemokines in macrophages and fibroblastic cells.


Asunto(s)
Quimiocinas/genética , Citocinas/genética , Dalbergia/química , Flavonoides/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Extractos Vegetales/farmacología , Madera/química , Animales , Quimiocinas/metabolismo , Citocinas/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Flavonoides/química , Flavonoides/aislamiento & purificación , Ratones , Estructura Molecular , Fosforilación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Células RAW 264.7
19.
Fitoterapia ; 158: 105162, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35217119

RESUMEN

Six new 2-(2-phenylethyl)chromone dimers (1-6) were isolated from ethyl ether extract of red soil agarwood of Aquilaria crassna from Vietnam by LC-MS-guided fractionation procedure. Their structures were unambiguously elucidated based on HRESIMS, 1D and 2D NMR spectra. The absolute configuration of 2-(2-phenylethyl)chromone dimers was determined by comparison of the experimental and computed ECD spectra. Compound 6 displayed cytotoxicity against the human myeloid leukemia cell line (K562) with an IC50 value of 39.49 µM.


Asunto(s)
Cromonas , Thymelaeaceae , Cromatografía Liquida , Cromonas/química , Flavonoides/química , Humanos , Estructura Molecular , Suelo , Espectrometría de Masas en Tándem , Thymelaeaceae/química , Madera/química
20.
J Ethnopharmacol ; 284: 114764, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34687835

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Haematoxylum campechianum L., is a well-known plant in the southeast region of Mexico, where it is named as "palo tinto" or "palo de Campeche", in English there are vernacular names such as "redwood", "bloodwood tree" or "campeachy wood". Traditional medicine refers its use for the treatment of different disorders including depression. AIM OF THE STUDY: Considering the traditional use of this plant for the alleviation of depression, the aim of this study was the evaluation of the anxiolytic effect of the methanolic and hydroalcoholic extracts from the heartwood of Haematoxylum campechianum L., and the sappanchalchone (Sapp). Additionally, it is presented the characterization of the new compound 4-hydroxyhematoxylol (2) isolated from the hydroalcoholic extract. MATERIAL AND METHODS: The anxiolytic effect of the extracts and Sapp was evaluated by using the Elevated Plus Maze (EPM) additionally the sedative effect was assessed with the Open Field Test (OFT). The chemical characterization of Sapp and 2 was performing by 1D and 2D NMR experiments. RESULTS: The EPM test showed that the administration of the plant extracts increased the percentage of time spent in open arms (76.32 ± 6.35 and 66.68 ± 20.64%, respectively for the methanolic and hydroalcoholic extracts), whereas the administration of Sapp increased the percentage of time spent in open arms by 60.07 ± 14.28%, these results are similar to Diazepam (DZP, positive control) which caused an increment of 74.06 ± 23.42%. For the OFT, all of the doses evaluated for both extracts and Sapp diminished the number of rearing (R) and total corssing (TC) behavior in a similar way to the positive control (DZO) and statistically different with respect to the vehicle. CONCLUSION: The results obtained showed that the polar extracts from the heartwood of Haematoxylum campechianum L. possess both anxiolytic and sedative effect and that the chalcone-type compound Sapp, isolated from the methanolic extract, is partially responsible of these activities.


Asunto(s)
Ansiolíticos/uso terapéutico , Ansiedad/tratamiento farmacológico , Chalconas/uso terapéutico , Fabaceae/química , Extractos Vegetales/uso terapéutico , Madera/química , Administración Oral , Animales , Ansiolíticos/química , Chalconas/química , Masculino , Ratones , Ratones Endogámicos ICR , Estructura Molecular , Extractos Vegetales/química
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