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1.
Oral Health Prev Dent ; 18(3): 549-554, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32515427

RESUMO

PURPOSE: Resin infiltration may be a barrier for bleaching gels. The aim of this study was to compare dental bleaching effectiveness using low-concentration gels on heavily or mildly stained teeth that were or were not treated with resin infiltration agents. MATERIALS AND METHODS: Forty bovine enamel surfaces were submitted to demineralisation, after which two staining protocols were performed. Twenty specimens were immersed in a staining broth for 24 h (Lab 1) or 7 days (Lab 2). Ten specimens of each group received resin infiltrant application following the manufacturer's recommendation. All specimens were bleached using 15% carbamide peroxide gel for 14 days (8 h daily). Colour measurement was performed using a reflectance spectrophotometer at three time points: baseline, after staining, and after bleaching. Data (CIEDE00) were analysed using Student's t-test (p < 0.05). RESULTS: No statistically significant differences were observed in Lab 1 (p = 0.560). For Lab 2, statistically significant differences were detected (p = 0.031). Once bleaching was achieved to some degree (Lab 2), the resin infiltrant may have behaved as a semipermeable barrier to the carbamide peroxide gels. CONCLUSION: Bleaching treatment was effective on mildly pigmented tooth surfaces. On the other hand, in comparison to the control group, the heavily pigmented surfaces bleached less in the presence of the resin infiltrant, possibly due to the lack of free radicals penetrating into the substrate.


Assuntos
Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Animais , Peróxido de Carbamida , Bovinos , Esmalte Dentário , Combinação de Medicamentos , Humanos , Resinas Vegetais
2.
Planta Med ; 86(9): 643-654, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32365391

RESUMO

As part of our ongoing search for antiprotozoal natural products from plants, we examined different resins from the Burseraceae family. The dichloromethane extract obtained from myrrh, the oleo-gum-resin of Commiphora species, showed promising in vitro activity against Plasmodium falciparum with an IC50 value of 1 µg/mL. Bioactivity-guided fractionation led to the isolation and characterization of 18 sesquiterpenoids, namely, ß-elemene (1: ), elemyl acetate (2: ), curzerenone (3: ), 8-hydroxyisogermafurenolide (4: ), 2-methoxyisogermafurenolide (5: ), 8-epi-2-methoxyisogermafurenolide (6: ), furanodienone (7: ), 1(10)Z,4Z-furanodien-6-one (8: ), rel-2R-methyl-5S-acetoxy-4R-furanogermacr-1(10)Z-en-6-one (9: ), (1(10)E)-2-methoxy-8,12-epoxygermacra-1(10),7,11-trien-6-one (10: ), 2R-methoxyfuranodiene (11: ), 2-acetyloxyglechomanolide (12: ), 8-epi-2-acetyloxyglechomanolide (13: ), (1R,2R,4S)-1,2-epoxyfuranogermacr-10(15)-en-6-one (14: ), hydroxylindestrenolide (15: ), isohydroxylindestrenolide (16: ), myrrhone (17: ), and myrrhterpenoid O (18: ). Moreover, nine (nor-)triterpenoids were isolated: mansumbinol (19: ), mansumbinol epoxide (20: ), mansumbinone (21: ), mansumbin-13(17)-en-3,16-dione (22: ), 3,4-seco-mansumbinoic acid (23: ), rel-20S-hydroxy-dammar-24-en-3,16-dione (24: ), rel-(16S,20S)-dihydroxydammar-24-en-3-one (25: ), cycloart-24-en-1α,2α,3ß-triol (26: ), and 3ß-isovaleroyloxycycloart-24-en-1α,2α-diol (27: ). All compounds were identified by MS and NMR spectroscopic analyses. To the best of our knowledge, compounds 5, 6, 12, 13, 16, 18: , and 20: are reported for the first time. All isolated compounds were tested in vitro for activity against P. falciparum and cytotoxicity. The sesquiterpene 7: and the triterpene 25: were the most active compounds found in this study with IC50 values of 7.4 and 2.8 µM, respectively.


Assuntos
Antimaláricos , Commiphora , Extratos Vegetais , Resinas Vegetais , Terpenos
3.
Phytochemistry ; 173: 112299, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32113066
4.
Dent Mater ; 36(3): 343-352, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31924386

RESUMO

OBJECTIVE: The structure of the polymer phase of dental resin-based-composites is highly sensitive to photo-polymerisation variables. The objective of this study was to understand how different polymer structures, generated with different photo-polymerisation protocols, respond to thermal perturbation. METHODS: Experimental resins were prepared from a series of Bis-GMA/TEGDMA blends (40/60, 50/50 and 60/40 wt.%), with either Camphorquinone/DMAEMA or Lucirin TPO as the photo-initiator system. Resins were photo-polymerised, in a disc geometry, at either relatively 'high' (3000 mW cm-2 for 6 s) or 'low' (300 mW cm-2 for 60 s) irradiances ensuring matched radiant exposures (18 J cm-2). Specimens were heated, from 20-160 °C at a rate of 5 °C min-1, whilst simultaneous synchrotron X-ray scattering measurements were taken at 5 °C increments to determine changes in polymer chain segment extension and medium-range order as a function of temperature. For each unique resin composition (n = 3), differential scanning calorimetry was used to measure glass transition temperatures using the same heating protocol. A paired t-test was used to determine significant differences in the glass transition temperature between irradiance protocols and photo-initiator chemistry at ɑ = 0.05. RESULTS: Resins pre-polymerised through the use of TPO and or high irradiances demonstrated a reduced rate of chain extension indicative of lower thermal expansion and a larger decrease in relative order when heated below the glass transition temperature. Above the transition temperature, differences in the rate of chain extension were negligible, but slower converted systems showed greater relative order. There was no significant difference in the glass transition temperature between different photo-initiator systems or irradiance protocols. SIGNIFICANCE: The evolution of chain extension and medium-range order during heating is dependent on the initial polymer structure which is influenced by photo-polymerisation variables. Less ordered systems, generated at faster rates of reactive group conversion displayed reduced chain extension below the glass transition temperature and maintained lower order throughout heating.


Assuntos
Resinas Compostas , Resinas Sintéticas , Bis-Fenol A-Glicidil Metacrilato , Teste de Materiais , Polietilenoglicóis , Polimerização , Ácidos Polimetacrílicos , Resinas Vegetais , Temperatura
5.
J Nat Med ; 74(1): 200-211, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31691185

RESUMO

Resin glycosides are well known as the purgative ingredients, which are characteristic of convolvulaceous plants. Calystegia hederacea Wall. is a perennial herbaceous vine that is widespread throughout India and East Asia. All parts of this plant are used for the treatment of menoxenia, gonorrhea, etc. Alkaline hydrolysis of the crude resin glycoside fraction of the whole plants of C. hederacea yielded four new glycosidic acids, calyhedic acids A, B, C, and D, along with two known glycosidic acids, calysolic acids A and C, and three known organic acids, 2S-methylbutyric, tiglic, and 2R,3R-nilic acids. Their structures were characterized on the basis of spectroscopic data and chemical evidence. Calyhedic acids A, B, and D were penta-, hexa-, and hepta-glycosides of 12S-hydroxyhexadecanoic acid, respectively, and cayhedic acid C was an isomer of calyhedic acid D, in which the 12S-hydroxyhexadecanoyl residue of calyhedic acid D was replaced by a 11S-hydroxyhexadecanoyl residue. Additionally, cytotoxic activity toward HL-60 human promyelocytic leukemia cells of the crude resin glycoside fraction, the glycosidic acid fraction, calyhedic acid A, and calysolic acid A from C. hederacea was evaluated. Furthermore, to clarify the structure-activity relationship of resin glycosides, the activities of six genuine resin glycosides with calysolic acid A or calysolic acid C as the glycosidic acid, which were isolated from C. soldanella, were examined. Among them, the crude resin glycoside fraction and five genuine resin glycosides with macrolactone structures demonstrated clear cytotoxic activities, while the glycosidic acid fraction, calyhedric acid A, calysolic acid A, and a genuine non-macrolactone-type resin glycoside were either inactive or exhibited weaker activity than the tested macrolactone-type resin glycosides.


Assuntos
Calystegia/química , Glicosídeos/química , Resinas Vegetais/química , Humanos , Hidrólise , Estrutura Molecular , Oligossacarídeos , Plantas Medicinais/química , Relação Estrutura-Atividade
6.
J Nat Med ; 74(1): 323-330, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31555997

RESUMO

Agarwood is a type of resinous wood found in the trunks of Aquilaria and some other genera. It is widely used as an herbal medicine for sedation, detoxification, and treatment of stomachaches, as well as for incense sticks. However, the number of source plants is decreasing, and in 2005, they were added to Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). To identify source species of agarwood, we previously developed a DNA-barcoding method using resin deposition sites. In this study, to identify additional agarwood source species, the barcoding method was applied to source plants and commercial agarwood samples collected from Sumbawa, Lombok, Sulawesi, and Kalimantan in Indonesia, a major agarwood-producing country. In addition, the method was also applied to incense stick samples labeled as agarwood. As a result, several samples were identified as Gyrinops, which is not currently listed as an agarwood source plant in the Japanese standards for non-Pharmacopoeial crude drugs 2018 (Non-JPS 2018). From the viewpoint of securing future resources, these findings suggest that Gyrinops species should, therefore, be added to the list of agarwood source species.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Plantas Medicinais/química , Resinas Vegetais/uso terapêutico , Thymelaeaceae/química , Thymelaeaceae/classificação , Comércio , DNA , Espécies em Perigo de Extinção , Indonésia , Internacionalidade , Fitoterapia/métodos , Plantas Medicinais/classificação
7.
J Nat Med ; 74(1): 98-105, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31392566

RESUMO

Agarwood, which is used as medicine and incense, contains sesquiterpenes and chromones. Agarotetrol is a chromone derivative found in high concentrations in the water-extract fraction of agarwood and thus may be present in pharmaceutical products made from decoctions of agarwood. Agarotetrol has been reported to be present at the early stages of cell death in calli. We therefore examined the presence of agarotetrol in medical- and incense-grade agarwood, in agarwood-source plants lacking resin deposits, and in artificially made agarwood. Agarotetrol appeared as a large peak in the HPLC chromatograms of all samples of medical-grade and artificially made agarwood, and in most incense-grade agarwood samples. In contrast, agarwood samples lacking resin deposits did not contain agarotetrol. These results show that agarotetrol is characteristic of resin formation. Agarotetrol was also detected in decoctions of agarwood. A newly developed TLC method for the detection of agarotetrol in agarwood is described.


Assuntos
Cromonas/análise , Cromonas/química , Resinas Vegetais/análise , Thymelaeaceae/química , Cromatografia Líquida de Alta Pressão , Extratos Vegetais , Resinas Vegetais/química , Sesquiterpenos/metabolismo
8.
Mol Genet Genomics ; 295(2): 327-341, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31735985

RESUMO

Pine resin, which typically consists of terpenoids, is a natural product used in various industrial applications. Oleoresin can be obtained from the xylem tissue by wounding the stem bark. Pinus massoniana (masson pine) is an important resin-tapping tree species that originated in southern China. Masson pines with different genetic backgrounds typically have different resin-yielding capacities (RYCs). However, the mechanisms underlying high resin yield in masson pines are unclear. The aim of this study was to identify the possible genetic regulation pathways and functional genes that influence the resin yield. In this study, we conducted transcriptomic and metabolomic studies of masson pine secondary xylem with high, medium, and low RYCs. A total of 230,068 unigenes and 3894 metabolites were identified from the tissue of the secondary xylem. Several differentially expressed regulation factors, including WRKY, bHLH, and ERF, and functional genes such as PKc and LRR-RLKs, were identified among these masson pines. The Kyoto Encyclopedia of Genes and Genomes pathways were mainly focused on diterpenoid biosynthesis, plant hormone signal transduction, and ABC transporters. Furthermore, integration of the transcriptomic and metabolomic data indicated that the PKc- and LRR-RLK-related regulatory and metabolic pathways may play critical roles in the biosynthesis of terpenoids. These above results improve our understanding of the biosynthesis mechanism of oleoresin in P. massoniana and facilitate further research work into the functional analysis of these candidate genes.


Assuntos
Redes e Vias Metabólicas/genética , Pinus/genética , Resinas Vegetais/metabolismo , Transcriptoma/genética , China , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Metabolômica/métodos , Pinus/metabolismo , Extratos Vegetais/biossíntese , Extratos Vegetais/genética , Terpenos/metabolismo , Xilema/genética , Xilema/metabolismo
9.
Phytochemistry ; 170: 112197, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31759268

RESUMO

Dragon's blood is the colloquial name for the red resin produced by tree species in the genus Dracaena (Asparagaceae), and the resin is directly involved in plant defensive mechanisms against pathogen and herbivore attack. It is also widely used in traditional folk medicine due to its antiviral, antimicrobial and antitumor activities. In the present work, a method using solid phase microextraction combined with two-dimensional gas chromatography with time-of-flight mass spectrometric detection was developed for the analysis of resin from five Dracaena species, namely Dracaena cinnabari Balf. f., D. serrulata Baker, D. ombet Heuglin ex Kotschy & Peyr., D. draco subsp. draco, and D. draco subsp. ajgal. Twenty terpenoid components in the resins of the five species were identified after comparative study of the volatile metabolite profiles. Monoterpenes were found to be species specific, and the observed differences might be further investigated as a possible means of identifying chemotaxonomic markers. In addition, for the first time, we describe the terpenoid volatile profiles of D. ombet and D. serrulata resins.


Assuntos
Dracaena/química , Compostos Fitoquímicos/análise , Resinas Vegetais/análise , Terpenos/análise , Cromatografia Gasosa , Espectrometria de Massas , Microextração em Fase Sólida , Especificidade da Espécie
10.
Eur J Med Chem ; 188: 111974, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31883489

RESUMO

A series of 28 novel 1,2,3-triazole hybrids of myrrhanone B have been designed and synthesized by employing regioselective Cu catalyzed Huisgen 1,3-dipolar cycloaddition reaction in highly efficient manner. All the synthesized analogues were assessed for their antiproliferative potential against A549 (Lung), DU145 (Prostate), MDA-MB-231 (Breast), SiHa (Cervical), U87MG (Glioblastoma), PC-3 (Prostate), HT-29 (Colon), L132 (Normal lung) cell lines. Further, the synthesized hybrids have also been screened for anti-inflammatory activity (TNF-α and IL-1ß) and α-glucosidase inhibitory activity. The biological results revealed that compound 11 (meta hydroxy phenyl 1,2,3-triazole) and compound 29 (deoxyuridine 1,2,3-triazole) found to be the most potent antiproliferative ones against PC-3 cell line. Compound 11 (IC50: 6.57 ± 0.62 µM) showed six folds more potent than parent compound 1 (IC50: 40.67 ± 2.2 µM) and displayed almost identical inhibitory activity with standard doxorubicin (IC50: 5.05 ± 0.25 µM), whereas compound 29 (IC50: 10.85 ± 0.90 µM) exhibited four folds more potent than parent myrrhanone B (1). In view of potent activity of compounds 11 and 29 they have been subjected to detailed flowcytometry analysis. Compound 29 treated cells significantly increased the SubG1 population of cells indicative of apoptosis compared to compound 11. Further, the results of anti-inflammatory studies indicated that compounds 3, 6, 9, 27, 28, 29 and 30 exhibited significant inhibitory activity against both TNF-α and IL-1ß than the parent compound 1. Interestingly, compound 27 exhibited good activity towards inflammatory cytokines TNF-α (IC50: 7.83 ± 0.95 µM). Interestingly, α-glucosidase inhibitory assay results revealed that compounds 14 (IC50: 2.77 ± 0.59 µM) and 16 (IC50: 4.12 ± 0.77 µM) as the most potent ones. In fact, compound 14 exhibited highest activity and found to be several times more potent than the parent compound 1 as well as standard acarbose (IC50: 2124 ± 170 µM).


Assuntos
Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Commiphora/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Triazóis/farmacologia , Triterpenos/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Humanos , Estrutura Molecular , Resinas Vegetais , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Triterpenos/síntese química , Triterpenos/isolamento & purificação
11.
Food Chem ; 309: 125656, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31699558

RESUMO

The adulteration of honey is generally a safety and quality concern for consumers and the industry as a whole. Resin technologies allow harmful substances to enter honey, creating substandard honey, which can enter the market. Thus, it is necessary to identify such illegal products quickly and easily. In this study, HPLC-ECD combined with chemometrics was used to identify raw acacia honey that had been treated with macroporous adsorption resins. The chromatography fingerprints of 46 honey samples were established, and principal component analysis (PCA) and the OPLS-DA identified that differences in some of the chromatographic peaks could be used to distinguish raw from resins-treated raw honeys. 100% correct classification was achieved with test samples, based on the chromatographic peaks identified. These results show that HPLC-ECD, combined with chemometric methods, can identify correctly resins-treated honey and can be applied for the quality control of honey.


Assuntos
Acacia/química , Cromatografia Líquida de Alta Pressão/métodos , Mel/análise , Resinas Vegetais/química , Acacia/metabolismo , Adsorção , Análise Discriminante , Análise dos Mínimos Quadrados , Porosidade , Análise de Componente Principal
12.
Food Chem ; 309: 125695, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704070

RESUMO

Developing food structures that combine material properties from two or three components is intriguing as well as challenging. This study reports a simple technique for co-solvation of two hydrophobic biopolymers in a neutral aqueous solution. The process suspended rice proteins (RPs) and shellac at pH 12 with a one-step adjustment to pH 7. Results from scanning electron microscopy, polyacrylamide gel electrophoresis, and fluorescence studies showed that shellac-RP complexes (SRPs) nucleated through hydrophobic attractions between the two biopolymers. As a result, the refolding of the backbones of RPs was resisted, leading to formation of spherical SRPs with less compactness and larger sizes than untreated RPs. The nanoscale spheres were induced with Ca2+ to structural transition to ribbons or networks. The tunable structures were used to entrap and deliver apigenin for improved, controllable cellular uptake in a HepG-2 cell model compared with free apigenin.


Assuntos
Apigenina/metabolismo , Oryza/metabolismo , Proteínas de Plantas/química , Resinas Vegetais/química , Apigenina/química , Apigenina/farmacologia , Proliferação de Células/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Proteínas de Plantas/metabolismo , Dobramento de Proteína
13.
Mater Sci Eng C Mater Biol Appl ; 107: 110309, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761185

RESUMO

Release behaviors of drugs from drug deliveries are crucial for the enhancement of therapy efficiency, reduction of toxicity and patient compliance. Herein, antisolvent crystallization is employed to coat methlyene blue (MB)-loaded silica by shellac precipitation (silica-MB@shellac), which is simultaneously induced by outward diffusion of H+ ions from particular silica-MB. The encapsulation of shellac shell on silica-MB modulates the aggregation state of MB, which endows silica-MB@shellac a decreased MB's thermal stability, enhanced photoluminescence intensity, improved stability against in vitro reduction by ascorbic acid and retained photodynamic therapy activity. From the absorbance of MB supernatant obtained during incubation, the concentrations of MB monomers and dimers are determined via a non-linear regression analysis to investigate the influence of shellac coating on MB's release mechanisms from silica-MB@shellac. According to the simulated models, small diffusion constants of MB are caused by limited diffusion through shellac shells with high compaction degrees. These are observed for samples synthesized under high supersaturation degree during antisolvent crystallization. High degree of supersaturation is achieved through increasing shellac concentration, additive amount and dropping rate of antisolvent, as well as decreasing pH values of aqueous buffers as antisolvent. Furthermore, a combined mechanism of Fickian diffusion and Case-IΙ relaxation is proposed to describe the release behaviors of MB monomer and dimers from silica-MB@shellac. Therefore, this work may shed light on the encapsulation method of polymer on drug-loaded powders and the control of aggregation states of photosensitizers to promote the photoluminescence intensity, photodynamic therapy efficiency and controlled release behaviors.


Assuntos
Azul de Metileno/química , Azul de Metileno/farmacocinética , Fármacos Fotossensibilizantes/química , Resinas Vegetais/química , Dióxido de Silício/química , Cristalização , Concentração de Íons de Hidrogênio , Cinética , Teste de Materiais , Fotoquimioterapia
14.
Pak J Pharm Sci ; 32(5): 2167-2173, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31813884

RESUMO

Shilajit, a blackish-brown exudation obtained from steep rocks of different mountains, has been longly used as a therapeutic agent in traditional medicine. The present study was designed to evaluate the antioxidant, cytotoxic and hyperalgesia-suppressing activity of the aqueous and DMSO extracts of a native Shilajit. The antioxidant and cytotoxic effects of Shilajit extracts was determined using DPPH scavenging activity and MTT assay methods, respectively. In order to examine the hyperalgesia-suppressing activity of the Shilajit aqueous extract the STZ-induced diabetic animals were subjected to oral administration of the extract (50, 100 and 200 mg/kg daily) for six weeks followed by evaluating the behavioral examination (hot plate and tail flick tests) compared to those of diabetic control (Sham) and vehicle groups. The obtained results of antioxidant evaluation of Shilajit represented scavenging activity of 50% at concentration of 2500 µg/mL and 6000 µg/mL in the case of aqueous and DMSO extracts, respectively. Cytotoxic study of water extract of Shilajit revealed IC50 of 727.5±1.9 µg/mL and 1103±3.2 µg/mL on cell lines of MCF-7 (breast cancer) and A549 (lung cancer), respectively. Thermal pain response examination of diabetic rats treated with aqueous extract of Shilajit (100 mg/kg and 200 mg/kg) for six weeks reduced hyperalgesia compared to vehicle and Sham groups. To sum up, considering the moderate antioxidant and hyperalgesia-suppressing activity of this native Shilajit make it as a suitable candidate for further investigation after isolation and characterization of the active compounds.


Assuntos
Antioxidantes/farmacologia , Citotoxinas/farmacologia , Hiperalgesia/tratamento farmacológico , Minerais/química , Resinas Vegetais/química , Células A549 , Animais , Linhagem Celular Tumoral , Humanos , Células MCF-7 , Masculino , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
15.
An Acad Bras Cienc ; 91(4): e20180302, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800694

RESUMO

The volume of global gross banana exports reached a record of 117.9 million tonnes in 2015 (FAO 2017), which agro-industrial wastes derived as the pseudo-stem, rachis and leaves do not have an industrial application instead they are discarded. This research study applies full factorial design and response surface methodology to determine the effect of pressing temperature and resin content on density (D), moisture (M), water absorption (WA), water swelling (WS), module of rupture (MOR), module of elasticity (MOE) and formaldehyde content (FC) of particle board made of banana pseudo-stem. A 22 factorial design was performed, factors considered were resin and temperature. The low level of resin was 15% in the coarse fiber (CF) and 35% in fine fiber (FF); high level as 25% CF and 45% FF. Temperature levels were 150ºC and 170ºC respectively. The boards met all quality parameters except ones with low resin content that didn't meet WS parameter. Furthermore, resin affected positively on WA, FC and MOE, and decreased D, WS and MOR values. Meanwhile, temperature affected negatively on D, WS, and increased FC, WA, MOE, MOR properties; none of the factors affected M response. Process conditions were optimized to 162.61°C and 43.15% FF, 23.97% CF.


Assuntos
Resíduos Industriais , Teste de Materiais , Musa , Caules de Planta , Eliminação de Resíduos/métodos , Resinas Vegetais/análise , Elasticidade , Temperatura , Resistência à Tração
16.
Molecules ; 24(23)2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31801194

RESUMO

Two new octanorlanostane-type triterpenes, euphraticanoids A and B (1 and 2), two new trinorsesquiterpenoids, euphraticanoids C and D (3 and 4), and eight known triterpenoids (5, 6, 8-13) along with one steroid (7) were isolated from Populus euphratica resins. The structures of these new compounds, including their absolute configurations, were characterized by spectrocsopic, chemical, and computational methods. Biological evaluation revealed that compounds 4, 7-9, 12, and 13 display neuroprotective activities in H2O2-induced HT-22 cells with 4, 8, and 9 occurring in a concentration-dependent manner and 7, 12, and 13 reaching the maximum effects at 20 µM. Meanwhile, the neuroprotective properties of all isolates were accessed using glutamate-induced SH-SY5Y cells and disclosed that compounds 3, 4, 8, and 9 could dose-dependently protect neural cell injury in a concentration range of 10-40 µM. Finally, a brief structure-activity relationship was briefly discussed.


Assuntos
Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Populus/química , Resinas Vegetais/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Triterpenos/química , Triterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Relação Estrutura-Atividade
17.
Molecules ; 24(22)2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31717646

RESUMO

A method has been developed for the separation and quantification of terpenic compounds typically used as markers in the chemical characterization of resins based on capillary liquid chromatography coupled to UV detection. The sample treatment, separation and detection conditions have been optimized in order to analyze compounds of different polarities and volatilities in a single chromatographic run. The monoterpene limonene and the triterpenes lupeol, lupenone, ß-amyrin, and α-amyrin have been selected as model compounds. The proposed method provides linear responses and precision (expressed as relative standard deviations) of 0.6% to 17%, within the 0.5-10.0 µg mL-1 concentration interval; the limits of detection (LODs) and quantification (LOQs) were 0.1-0.25 µg mL-1 and 0.4-0.8 µg mL-1, respectively. The method has been applied to the quantification of the target compounds in microsamples. The reliability of the proposed conditions has been tested by analyzing three resins, white copal, copal in tears, and ocote tree resin. Percentages of the triterpenes in the range 0.010% to 0.16% were measured using sample amounts of 10-15 mg, whereas the most abundant compound limonene (≥0.93%) could be determined using 1 mg portions of the resins. The proposed method can be considered complementary to existing protocols aimed at establishing the chemical fingerprint of these kinds of samples.


Assuntos
Cromatografia Líquida , Resinas Vegetais/química , Terpenos/análise , Terpenos/química , Cromatografia Líquida/métodos , Limite de Detecção , Estrutura Molecular
18.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683728

RESUMO

Capsaicin, which mainly comes from pepper, exhibits anticancer, antioxidant, and anti-obesity properties. This work aims to construct a comprehensive technology for the extraction and purification of capsaicin from capsicum oleoresin. The tunable aqueous polymer phase impregnated HZ816 resins were selected in extraction step. In the extraction process, 3 g of impregnated HZ816 macroporous resin was employed per system. The results showed that a higher molecular weight of Polyethylene glycol (PEG) and 1-ethyl-3-methyl imidazolium acetate ([Emim] [OAc]) are more beneficial to the improvement of the yield of capsaicin. Screening experiment using fractional factorial designs indicated that the amount of sample loading, pH, and concentration of [Emim] [OAc] and PEG 6000 significantly affect the yield of capsaicin. Mathematical models of capsaicin yield in tunable aqueous polymer-phase impregnated resins were established and optimum condition was obtained using response surface methodology. The optimum impregnated phase was the polymer phase of an aqueous two-phase system which contained 18.5% (w/w) PEG6000, 15% (w/w) sodium citrate, and 10% (w/w) [Emim] [OAc] at pH 6.5. Under the optimal conditions, the yield of capsaicin reached 95.82% when the extraction system contains 0.25 g capsicum oleoresin. Ultimately, capsaicinoids extract was purified by reverse-phase resin (SKP-10-4300) chromatographic column. The capsaicin recovery and purity achieved 85% and 92%, respectively.


Assuntos
Capsaicina/isolamento & purificação , Capsicum/química , Cromatografia/métodos , Extratos Vegetais/química , Polímeros/química , Resinas Vegetais/química , Água/química , Adsorção , Concentração de Íons de Hidrogênio , Líquidos Iônicos/química , Peso Molecular , Polietilenoglicóis/química , Solventes
19.
Molecules ; 24(22)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739575

RESUMO

Organic wood extractives-resin acids-significantly contribute to an increase in the toxicity level of pulp and paper industry effluents. Entering open ecosystems, resin acids accumulate and have toxic effects on living organisms, which can lead to the ecological imbalance. Among the most effective methods applied to neutralize these ecotoxicants is enzymatic detoxification using microorganisms. A fundamental interest in the in-depth study of the oxidation mechanisms of resin acids and the search for their key biodegraders is increasing every year. Compounds from this group receive attention because of the need to develop highly effective procedures of resin acid removal from pulp and paper effluents and also the possibility to obtain their derivatives with pronounced pharmacological effects. Over the past fifteen years, this is the first report analyzing the data on distribution, the impacts on living organisms, and the microbial transformation of resin acids. Using the example of dehydroabietic acid-the dominant compound of resin acids in effluents-the review discusses the features of interactions between microorganisms and this pollutant and also highlights the pathways and main products of resin acid bioconversion.


Assuntos
Resinas Vegetais/química , Abietanos/química , Biodegradação Ambiental , Diterpenos/química , Estrutura Molecular
20.
Chem Biodivers ; 16(12): e1900506, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31633273

RESUMO

Perfumes have always been products of great importance, mainly composed of natural, valuable and vegetal raw materials. Today, some of them have completely disappeared in perfumery, even though they are part of our cultural heritage and were commonly used in the past. Balm of Judea is one of the most noble, rare and fascinating ingredient long used in perfumery and medicine, that is missing today. After years of research, we collected a resin and an essential oil (steam distillation of fresh aerial parts) from Commiphora gileadensis (L.) C.Chr. native from Saudi Arabia and cultivated in Israel. The aims of this study were to i) identify the main reasons of the loss of the balm of Judea, ii) characterize the volatile composition of the resin and the essential oil and iii) evaluate their olfactory profile and assess their biological activity. Eighty-three compounds were identified in the resin, by a combination of GC-MS and GC/FID techniques, using direct injection and HS-SPME. α-Pinene (24.0 %), sabinene (43.8 %), ß-pinene (6.3 %) and cymene (3.6 %) were the main identified compounds, giving an intense, terpenic and lemony smell to the resin. Anti-inflammatory, wound-healing and whitening activities were highlighted. Sabinene (22.7 %), terpinen-4-ol (18.7 %), α-pinene (14.4 %) and cymene (13.6 %) were identified as the main components of the essential oil, giving a spicy, woody and lemony fragrance. Anti-inflammatory and whitening activities were emphasized.


Assuntos
Commiphora/química , Óleos Voláteis/química , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Commiphora/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Óleos Voláteis/isolamento & purificação , Componentes Aéreos da Planta/química , Componentes Aéreos da Planta/metabolismo , Resinas Vegetais/química , Resinas Vegetais/metabolismo , Microextração em Fase Sólida
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