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1.
Anticancer Agents Med Chem ; 23(6): 717-725, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36221890

RESUMO

BACKGROUND: Lung cancer is the leading cause of cancer-associated death and the first most diagnosed cancer in the world. More than 2 million new cases are diagnosed and 1.6 million people die due to lung cancer every year. It is urgent to explore novel drugs and approaches for lung cancer treatment. Cinobufotalin is a TCM isolated from dried toad venom, which has been used to treat lung cancer. However, the precise mechanism remains unclear. OBJECTIVE: This study was to investigate the mechanism of cinobufotalin treated in lung cancer. METHODS: Cell growth was identified by Cell Counting Kit-8 (CCK-8) assay. Besides, ferroptosis of lung cancer cells was determined by intracellular iron content, lactate dehydrogenase (LDH) release and mitochondrial membrane potential. Moreover, RNA levels and proteins were detected by quantitative reverse transcription-PCR (qRT-PCR) and Western blot (WB), respectively. In addition, the regulatory effect of hsa-miR-367-3p on TFRC was confirmed by luciferase reporter assay. RESULTS: This study indicated that cinobufotalin suppressed lung cancer cell growth through resibufogenin. Besides, cinobufotalin induced ferroptosis in lung cancer cells through resibufogenin. Moreover, cinobufotalin increased lncRNA LINC00597 level, whereas it downregulated hsa-miR-367-3p expression in lung cancer cells via resibufogenin. In addition, ferroptosis inducer transferrin receptor (TFRC) was the target of hsa-miR-367-3p, and lncRNA LINC00597 upregulates TFRC expression through sponging hsa-miR-367-3p in lung cancer cells. CONCLUSION: In summary, this study indicated that cinobufotalin induced ferroptosis to suppress lung cancer cell growth by lncRNA LINC00597/hsa-miR-367-3p/TFRC pathway via resibufogenin might provide novel therapeutic targets for lung cancer therapy.


Assuntos
Ferroptose , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , MicroRNAs/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Receptores da Transferrina , Proliferação de Células
2.
Bioresour Technol ; 324: 124614, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33434876

RESUMO

A solid acid catalyst prepared by sulfonated Sargassum horneri carbon was utilized for the esterification reaction of oleic acid and methanol. The formed amorphous carbon layers during carbonization and the access of sulfonic acid groups during sulfonation can catalyze the esterification reaction for biodiesel preparation efficiently. The catalyst was characterized by various methods to investigate its physical and chemical properties. With carbonization at 300 °C for 2 h followed by sulfonation at 90 °C for 5 h, the catalyst reached acid density of 1.40 mmol/g. The catalyst dosage, methanol/oleic acid (molar ratio), reaction temperature, and reaction time were optimized to 10 wt%, 15:1, 70 °C, and 3 h, respectively. Under the optimal condition, the conversion of oleic acid reached 96.4%. Additionally, the catalyst was regenerated after four cycles, with the conversion of oleic acid still reaching 95.4%.


Assuntos
Biocombustíveis , Sargassum , Carbono , Catálise , Esterificação
3.
RSC Adv ; 9(40): 23061-23070, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35514466

RESUMO

The oxidative cleavage of vegetable oils and their derivatives to produce bio-based aldehydes is a potentially useful process, although the aldehyde products are readily oxidized to carboxylic acids and thus seldom obtained in high yields. The present study developed a room-temperature method for the synthesis of bio-aldehydes via the oxidative cleavage of vegetable oil-derived epoxides, using H2WO4 as the catalyst, H2O2 as the oxidant, and t-BuOH as the solvent. Reactions were carried out at temperatures ranging from 25 to 35 °C for 3.5-10.5 h, and provided >99% conversion and >90% aldehyde yield. In particular, an approximately 97% yield was obtained at 25 °C after 10.5 h. As the reaction proceeded, the H2WO4 dissolved to form a W-containing anion. Several mesoporous Al-MCM-41 materials having different Si/Al ratios were hydrothermally synthesized and used as adsorbents to recover the catalyst by adsorbing these anions. The adsorption capacity of the Al-MCM-41 was found to increase with decreases in the Si/Al ratio. The Al-MCM-41 had little effect on the oxidative cleavage reaction at 25 °C, and thus could be directly added to the reaction system. The excellent anion adsorption performance of the Al-MCM-41 greatly improved the reusability of the H2WO4 catalyst. When using the Al-MCM-41 with the best adsorption performance, there was no significant decrease in the activity of the catalyst following five reuses.

4.
RSC Adv ; 9(45): 25967-25975, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35530987

RESUMO

The degradation of methylene blue (MB) using a novel dielectric barrier discharge plasma reactor coupled with activated carbon supported polyurethane foam (AC/PUF) was investigated in this paper. The plasma reactor combining a glass bead-packed bed and a microporous plate was developed. The AC/PUF provided sufficient contact area between carbon media and pollutants and hence revealed a good MB removal capacity. The effects of input voltage and initial MB solution concentration on MB degradation efficiency were examined. Kinetic study indicated that plasma and AC/PUF in the coupled system had a good synergistic effect in MB degradation. The degradation efficiency of 100 ppm MB solution could reach 97.9% with 10 min treatment in the coupled system, which was close to that obtained by plasma treatment alone for 30 min (97.5%). The COD removal in the plasma and AC/PUF coupled system (90.7%) was much higher than that obtained by plasma treatment followed by AC/PUF adsorption (58.3%). In addition, the energy yield (G 50) of the coupled system was up to 38.3 g kW-1 h-1, suggesting great energy efficiency of the system. Moreover, repeated use experiments of AC/PUF showed the good utilization potential of the coupled system. Finally, a possible degradation pathway of MB was proposed.

5.
Bioresour Technol ; 186: 334-337, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25818921

RESUMO

Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500°C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460°C to 560°C. The maximum UAME yield was obtained at the temperature of 500°C.


Assuntos
Temperatura Alta , Micro-Ondas , Ácidos Ricinoleicos/química , Ácidos Undecilênicos/isolamento & purificação
6.
Bioresour Technol ; 169: 800-803, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25106779

RESUMO

In this work, the role of Brønsted acid for furfural production in biomass pyrolysis on supported sulfates catalysts was investigated. The introduction of Brønsted acid was shown to improve the degradation of polysaccharides to intermediates for furfural, which did not work well when only Lewis acids were used in the process. Experimental results showed that CuSO4/HZSM-5 catalyst exhibited the best performance for furfural (28% yield), which was much higher than individual HZSM-5 (5%) and CuSO4 (6%). The optimum reaction conditions called for the mass ratio of CuSO4/HZSM-5 to be 0.4 and the catalyst/biomass mass ratio to be 0.5. The recycled catalyst exhibited low productivity (9%). Analysis of the catalysts by Py-IR revealed that the CuSO4/HZSM-5 owned a stronger Brønsted acid intensity than HZSM-5 or the recycled CuSO4/HZSM-5. Therefore, the existence of Brønsted acid is necessary to achieve a more productive degradation of biomass for furfural.


Assuntos
Ácidos/farmacologia , Biomassa , Biotecnologia/métodos , Furaldeído/metabolismo , Temperatura Alta , Ácidos Fosfóricos/farmacologia , Ácidos Sulfúricos/farmacologia , Catálise/efeitos dos fármacos , Sulfato de Cobre/farmacologia , Zeolitas/farmacologia
7.
Sheng Wu Gong Cheng Xue Bao ; 29(3): 358-69, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23789277

RESUMO

Effects of carbon sources (Na2CO3, NaHCO3 and glucose) and concentration of NaHCO3 on the growth density and lipid contents of Nannochloropsis oculata were studied. N. oculata preferred inorganic carbon to glucose, the growth density and lipid content of algae cultured with NaHCO3 were higher than that with glucose. The effects of concentration of NaHCO3 on growth density and lipid content were related to inoculation density and nitrogen level. In high nitrogen level, the concentration of NaHCO3 had little effect on the growth density, but in low nitrogen level, the growth density increased at first, and then decreased with the increase of concentration of NaHCO3. Based on the results we suggest that an optimum ratio of carbon to nitrogen was existed. Furthermore, we found the optimum ratio was changed with inoculation density. The optimum ratio of carbon to nitrogen was 3 when inoculation density was OD440 of 0.10, the optimum ratio increased to 5 with OD440 of 0.70. Concentration of NaHCO3 and ratio of carbon to nitrogen had significant effects on the lipid content and productivity. Lipid content reached the highest value when the ratio of carbon to nitrogen was 1 with experimental range of nitrogen level and inoculation density. The lipid productivity was 56.7 mg/(L.d) , and the EPA productivity was 6.5 mg/(L.d) at optimum cultivation condition with NaHCO3 as carbon source, the ratio of carbon to nitrogen at 1, the concentration of NaNO3 at 0.225 g/L, and the inoculation density with OD440 of 0.70.


Assuntos
Carbono/metabolismo , Ácidos Graxos/metabolismo , Fermentação , Microalgas/metabolismo , Estramenópilas/metabolismo , Carbono/química , Meios de Cultura , Técnicas de Cultura/métodos , Glucose/metabolismo , Metabolismo dos Lipídeos , Microalgas/crescimento & desenvolvimento , Densidade Demográfica , Estramenópilas/crescimento & desenvolvimento
8.
Environ Sci Technol ; 47(14): 7934-9, 2013 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-23772855

RESUMO

The technology of packed bed dielectric barrier discharge (DBD) plasma followed by a chemical absorption has been developed and was found to be an efficient way for decomposition treatment of sulfuryl fluoride (SO2F2) in simulated residual fumigant. The effects of energy density, initial SO2F2 concentration, and residence time on the removal efficiency of SO2F2 for the DBD plasma treatment alone were investigated. It was found that the SO2F2 could be removed completely when initial volume concentration, energy density, and residence time were 0.5%, 33.9 kJ/L, and 5.1 s, respectively. The removal mechanism of SO2F2 in the packed bed DBD reactor was discussed. Based on the detailed analysis of SO2F2 molecular stability and its exhaust products in the DBD plasma reactor, it was concluded that the energetic electrons generated in the packed bed DBD reactor played a key role on the removal of SO2F2, and the major decomposition products of SO2F2 detected were SO2, SiF4, and S (Sulfur). Among these products, SiF4 was formed by the F atom reacted with the filler-quartz glass beads (SiO2) in the packed bed DBD reactor. Aqueous NaOH solution was used as the chemical absorbent for the gaseous products of SO2F2 after plasma pretreatment. It was found that the gaseous products in the plasma exhaust could be absorbed and fixed by the subsequent aqueous NaOH solution.


Assuntos
Ácidos Sulfínicos/química , Absorção
9.
Sheng Wu Gong Cheng Xue Bao ; 29(12): 1865-9, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24660635

RESUMO

Nitrogen source is one of the important factors that affect the microalgae growth and lipid accumulation. We studied the effects of various nitrogen sources (i.e. NaNO3, CO(NH2)2, NH4Cl and CH3COONH4) and amount on the growth density, lipid yield, and eicosapentaenoic acid (EPA) content of Nannochloropsis oculata by single factor experimental method. The results show that N. oculata preferred NH4+ as nitrogen source rather than NO3- and CO(NH2)2. NH4+ could promote the growth and lipid accumulation of N. oculata. With the increase of nitrogen concentration, the biomass and the content of polyunsaturated fatty acid (PUFA) increased, but the content of lipid decreased. CH3COONH4 was the most suitable for growth, accumulation of lipid and EPA of N. oculata among the four investigated nitrogen sources. The optimal concentration was 5.29 mmol/L.


Assuntos
Ácido Eicosapentaenoico/metabolismo , Lipídeos/biossíntese , Microalgas/metabolismo , Nitrogênio/metabolismo , Estramenópilas/metabolismo , Lipídeos/isolamento & purificação , Microalgas/crescimento & desenvolvimento , Nitrogênio/análise , Estramenópilas/crescimento & desenvolvimento
10.
Carbohydr Res ; 353: 111-4, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22516168

RESUMO

Lignocellulose and other carbohydrates are being studied extensively as potential renewable carbon sources for liquid biofuels and other valuable chemicals. In the present study, a simple, sensitive, selective, and reliable HPLC method using a photodiode array (PDA) detector and an evaporative light scattering detector (ELSD) was developed for the simultaneous determination of important sugars (D(+)-cellobiose, glucose, xylose, and arabinose), furfural and 5-hydroxymethylfurfural (5-HMF) in lignocellulose hydrolysate. The analysis was carried out on an Aminex HPX-87H column (250 mm × 4.6 mm, 5 µm particle size). Ultra-pure water with 0.00035 M H(2)SO(4) was used as the mobile phase with a flow rate of 0.6 mL/min. The temperature of the ELSD drift tube was kept at 50 °C, the carrier gas pressure was 350 kPa, and the gain was set at 7. Furfural and 5-HMF were quantified on a PDA detector at 275 nm and 284 nm, respectively. The sugar concentrations were determined by ELSD. This method was validated for accuracy and precision. The regression equation revealed a good linear relationship (r(2) = 0.9986 ± 0.0012) within the test ranges. The method showed good reproducibility for the quantification of six analytes in corncob hydrolysate, with intra- and inter-day variations less than 1.12%. This method is also convenient because it allows the rapid analysis of the primary products of biomass hydrolysis and carbohydrate degradation.


Assuntos
Arabinose/análise , Cromatografia Líquida de Alta Pressão/métodos , Furaldeído/análogos & derivados , Furaldeído/análise , Glucose/análise , Xilose/análise , Zea mays/química
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