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1.
Bioresour Technol ; 347: 126678, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34999192

RESUMO

Periodic oxygen supplementation (A-O) strategy was proposed to improve pollutant removal and enhance bioresource production of photosynthetic bacteria (PSB). The A-O strategy obtained higher COD (91.4%) and NH4+-N (78.6%) removal compared with the non-oxygen supplementation (N-O) strategy, which was similar to the continuous oxygen supplementation (C-O) strategy. A-O strategy achieved the highest biomass concentration of 1338.5 mg/L. Bacteriochlorophyll and carotenoids concentration in the A-O strategy were 24.9-31.1% and 15.1-23.7% higher than those in the other two strategies; coenzyme Q10 concentration and content were 52.5% and 21.3% higher than that in the N-O strategy. The metabolomic analysis showed that the A-O strategy enhanced the tricarboxylic acid cycle after fumaric acid formation and ß-alanine metabolism, then caused higher biomass accumulation. The A-O strategy reduced the inhibition of photophosphorylation by oxidative-phosphorylation and maintained both characteristics. Hence, A-O might be an economic strategy for enhancing pollutant removal and bioresource production in PSB-based wastewater treatment.


Assuntos
Águas Residuárias , Purificação da Água , Biomassa , Bactérias Gram-Negativas , Oxigênio , Oxigenoterapia , Fotossíntese
2.
World J Microbiol Biotechnol ; 37(9): 161, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34436687

RESUMO

Shortage of water, energy, and bioresources in the world has led to the exploration of new technologies that achieve resource recovery from wastewater, which has become a new sustainable trend. Photosynthetic non-sulfur bacteria (PNSB), the most ancient photo microorganism, not only treats different wastewater types, but also generates PNSB cells, which are non-toxic bioresources and containing many value-added products. These bioresources can be used as raw materials in the agricultural, food, and medical industries. Therefore, PNSB or PNSB-based wastewater resource recovery technology can be simultaneously used to treat wastewater and produce useful bioresources. Compared with traditional wastewater treatment, this technology can reduce CO2 emissions, promote the N recovery ratio and prevent residual sludge disposal or generation. After being developed for over half a century, PNSB wastewater resource recovery technology is currently extended towards industrial applications. Here, this technology is comprehensively introduced in terms of (1) PNSB characteristics and metabolism; (2) PNSB wastewater treatment and bioresource recovery efficiency; (3) the relative factors influencing the performance of this technology, including light, oxygen, strains, wastewater types, hydraulic retention time, on wastewater treatment, and resource production; (4) PNSB value-added bioresources and their generation from wastewater; (5) the scale-up history of PNSB technology; (6) Finally, the future perspectives and challenges of this technology were also analysed and summarised.


Assuntos
Rhodospirillaceae/metabolismo , Águas Residuárias/microbiologia , Purificação da Água/métodos , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Águas Residuárias/química , Purificação da Água/instrumentação
3.
J Hazard Mater ; 402: 123561, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-32769004

RESUMO

A combined low-temperature-roasting and water-washing process is investigated as a hazard-free method to treat electrolytic manganese residue (EMR) and recover manganese. In this study, the phase transformation characteristics and a thermodynamics analysis of the low temperature roasting process of EMR are evaluated. In addition, the effects of temperature and time on the phase transformation of EMR in the roasting process and the washing characteristics of roasted EMR samples are also investigated. Results reveal that some unstable phases within EMR are transformed into more stable phases depending on the treatment time/temperature conditions used and EMR roasted for 60 min at 600 °C (R60min/600°C) exhibit the highest rate of manganese recovery, 67.12 %. After 25 min of deionized water washing, the concentration of manganese in solution from R60min/600°C material become stable, whereas after 6 washing cycles the concentration of manganese in the solution is < 0.005 g/L. The R60min/600°C material with three wash cycles results in a manganese-water solution concentration that is suitable for use in electrolytic manganese metal production. Finally, toxicity leaching tests show that the concentrations of ions present in the leaching solution are all lower than the regulatory limits mandated by the Chinese Integrated Wastewater Discharge Standard GB 8978-1996.

4.
Waste Manag ; 113: 105-117, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32526637

RESUMO

An efficient process is proposed for recovery of waste LiMn2O4 cathode material, which is one of the most commonly used cathode materials in LIBs. This report constitutes the precipitation thermodynamic analysis and separation experiments based on the water-leaching solutions during the processes of low-temperature calcination with (NH4)2SO4 and water-leaching. Precipitation thermodynamic analysis is undertaken to investigate the effects of initial concentration of the target solution, [N]T1, excess precipitant, and addition of (NH4)2SO4 on the manganese precipitation in the Mn2+-Li+-SO42--NH3-NH4+-CO32--H2O system. Moreover, the effects of initial concentration of the target solution, [N]T2, and excess precipitant on the lithium precipitation in the Li+-SO42--NH3-NH4+-CO32--H2O system are investigated. All these factors clearly influence the manganese and lithium precipitation, particularly the [N]T and the presence of excess precipitant in the system. The precipitation experimental results demonstrate that the optimal conditions are: a precipitation temperature of 35 °C; an excess coefficient of the precipitant of 2.4; the use of NHC-3 to precipitate the ML-3 solution; a maximum precipitation percentage of manganese of 99.96%; and an absence of Li2CO3 precipitation. The double-sulfate salts (Li(NH4)SO4 & (NH4)2SO4) evaporated and crystallised from the Li+/NH4+ solution are mixed with the waste LiMn2O4 cathode material for calcination and water leaching, for which the efficiencies of Li and Mn are 100% and 96.89%, respectively. The double-sulfate salts are calcined at 550 °C for 45 min to obtain the Li2SO4 product. Finally, the complete recovery and separation of Mn and Li in the waste LiMn2O4 cathode material are achieved.


Assuntos
Fontes de Energia Elétrica , Reciclagem , Eletrodos , Lítio , Temperatura
5.
Waste Manag ; 108: 28-40, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32335486

RESUMO

An efficient process for recycling waste LiMn2O4 cathode material is proposed in this research. This report constitutes low-temperature (NH4)2SO4 calcination mechanisms and water-leaching characteristics of the calcined samples. A calcination temperature range of 420.65-634.12 °C is determined by analysis of the TG-DSC curve under the conditions of heating from 25 to 1000 °C, with a molar ratio of n(2Li + Mn):n(NH4)2SO4 = 1:1 in air atmosphere. The sample calcined at 600 °C for 45 min when the excess coefficient of the (NH4)2SO4 was 1.1 exhibits optimal water-leaching efficiencies of the Li and Mn elements, which are approximately 100% and 96.73%, respectively. The macro-reaction mechanism of the waste LiMn2O4 cathode material calcined with (NH4)2SO4 is determined as the liquid-solid reaction by analysing the apparent morphologies of the calcined samples and their water-leaching residues under different calcination conditions. Moreover, the micro-reaction mechanism is investigated by analysing the phases of the calcined samples and their water-leaching residues under different calcination conditions. The free high-energy H+ released by the decomposition of the NH4+ generated by the molten (NH4)2SO4 play a key role in the entire calcination process. The spinel structure of the LiMn2O4 is broken and Li+ is released owing to the H+ bombarding the MnO bonds. Finally, the LiMn2O4 is converted into soluble sulphate salts, such as Li2Mn2(SO4)3 and MnSO4.


Assuntos
Fontes de Energia Elétrica , Lítio , Eletrodos , Reciclagem , Temperatura
6.
7.
J Am Chem Soc ; 142(14): 6467-6471, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32186873

RESUMO

A large-pore version of Mg-CUK-1, a water-stable metal-organic framework (MOF) with 1-D channels, was synthesized in basic water. Mg-CUK-1L has a BET surface area of 2896 m2 g-1 and shows stark selectivity for CO2 sorption over N2, O2, H2, and CH4. It displays reversible, multistep gated sorption of CO2 below 0.33 atm. The dehydrated single-crystal structure of Mg-CUK-1L confirms retention of the open-channel structure. The MOF can be loaded with organic molecules by immersion in hot melts, providing single crystals suitable for X-ray diffraction. trans-Azobenzene fills the channels in a 2 × 2 arrangement. Solid-state UV-vis spectroscopy reveals that azobenzene molecules undergo reversible trans-cis isomerization, despite being close-packed; this surprising result is confirmed by DFT-simulated UV-vis spectra.

8.
Water Environ Res ; 92(8): 1131-1141, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32056340

RESUMO

Photosynthetic bacteria (PSB) technology is a promising method for biomass, protein, pigments, and other value-added substances generation from wastewater. However, the above bioresources production efficiency is relatively low. In this work, a static magnetic field (SMF) was used to promote bioresources production. Results showed that SMF had positive effects on value-added substances production. With 0.35 Tesla (T) SMF, the PSB biomass, protein, carotenoids, and bacteriochlorophyll concentration were promoted by 31.1%, 22.6%, 56.7%, and 73.1% compared with the control group, respectively. Biomass yield finally reached 0.58 g biomass/g COD removal, which was promoted by 37.1%. The doubling time was shortened by 37.9% in 0.35 T group, showing that SMF can promote cell growth. With 0.35 T SMF, the intracellular NADH dehydrogenase and ATP synthase activities concentration increased by 23.4% and 29.1%, respectively, thus increased the ATP content by 38.0%. Succinic dehydrogenase activity concentration greatly increased by 609.0% at 48 hr, which potentially accelerated the tricarboxylic acid cycle and COD degradation as well as enhanced biomass production. PRACTITIONER POINTS: SMF promoted PSB bioresource production during wastewater treatment processing. Biomass, protein, carotenoids, and Bchl concentration were promoted by 31.1%, 22.6%, 56.7%, and 73.1%, respectively. PSB yield of 0.35 T group was promoted by 37.1% compared with the control group. SDH concentration of 0.35 T was promoted by 609.0% compared with the control group. Increased NADH and ATP synthase activity concentration by SMF enhanced energy metabolism.


Assuntos
Águas Residuárias , Purificação da Água , Bactérias , Campos Magnéticos , Fotossíntese
9.
Chem Commun (Camb) ; 56(8): 1286-1289, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31904031

RESUMO

Controlled partial decomposition of 2-selenonicotinic acid in the presence of Co2+ or Ni2+ resulted in the in situ formation of an unusual MOF based on triselenane ligands (RSeSeSeR) coordinated to M2+ centers as NSeN-pincers. Post-synthetic oxidation by treatment with aqueous H2O2 facilitates its solid-state conversion into a RSeO2- molecular coordination complex, which was tracked via powder X-ray diffraction studies and by single-crystal structural resolution of the final product.

10.
Med Chem ; 16(1): 104-118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30398118

RESUMO

OBJECTIVE: Due to the incidence of resistance, a series of sulfonamide-derived 1,2,4- triazoles were synthesized and evaluated. METHOD: The novel sulfonamide-derived 1,2,4-triazoles were prepared starting from commercial acetaniline and chlorosulfonic acid by sulfonylation, aminolysis, N-alkylation and so on. The antimicrobial activity of the synthesized compounds were evaluated in vitro by two-fold serial dilution technique. RESULTS: In vitro antimicrobial evaluation found that 2-chlorobenzyl sulfonamide 1,2,4-triazole 7c exhibited excellent antibacterial activities against MRSA, B. subtilis, B. typhi and E. coli with MIC values of 0.02-0.16 µmol/mL, which were comparable or even better than Chloromycin. The preliminary mechanism suggested that compound 7c could effectively bind with DNA, and also it could bind with human microsomal heme through hydrogen bonds in molecular docking. Computational chemical studies were performed on compound 7c to understand the structural features that are essential for activity. Additionally, compound 7c could generate a small amount of reactive oxygen species (ROS). CONCLUSION: Compound 7c could serve as a potential clinical antimicrobial candidate.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Sulfonamidas/farmacologia , Triazóis/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Bacillus/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Saccharomyces cerevisiae/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Triazóis/síntese química , Triazóis/química
11.
Bioresour Technol ; 278: 383-399, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30683503

RESUMO

Generating or recycling water and resources from wastewater other than just treating wastewater is one of the most popular trends worldwide. Photosynthetic bacteria (PSB) wastewater treatment and resource recovery technology is one of the most potential methods. PSBs are non-toxic and contain lots of value-added products that can be utilized in the agricultural and food industries. They are effective to degrade pollutants and synthesize useful biomass, thus realizing wastewater treatment, bioresource production, and eliminating waste sludge. If all the nutrients in wastewaters could be bio-converted by PSB, then pollutant reductions and economic benefits would be achieved. This review paper firstly describes and summarizes this technology, including PSBs classification, metabolism, and the market application. The feasibility, technical procedures, bioreactors, pollutant removal, and bioresource production are also summarized, compared and evaluated. Issues that concern the advantages and industrialization of this technologies at the plant scale are also discussed.


Assuntos
Bactérias/metabolismo , Fotossíntese , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Biomassa , Reatores Biológicos , Esgotos
12.
Eur J Med Chem ; 136: 165-183, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28494254

RESUMO

A novel series of benzimidazole-incorporated sulfonamide analogues were designed and synthesized with an effort to overcome the increasing antibiotic resistance. Compound 5c gave potent activities against Gram-positive bacteria and fungi, and 2,4-dichlorobenzyl derivative 5g showed good activities against Gram-negative bacteria. Both of these two active molecules 5c and 5g could effectively intercalate into calf thymus DNA to form compound-DNA complex respectively, which might block DNA replication to exert their powerful antimicrobial activity. Molecular docking experiments suggested that compounds 5c and 5g could insert into base-pairs of DNA hexamer duplex by the formation of hydrogen bonds with guanine of DNA. The transportation behavior of these highly active compounds by human serum albumin (HSA) demonstrated that the electrostatic interactions played major roles in the strong association of active compounds with HSA, and which was also confirmed by the full geometry calculation optimizations.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Benzimidazóis/farmacologia , Desenho de Fármacos , Sulfonamidas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Benzimidazóis/química , Bovinos , DNA/química , Relação Dose-Resposta a Droga , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Albumina Sérica/química , Relação Estrutura-Atividade , Sulfonamidas/química
13.
Sci Rep ; 5: 7697, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25571970

RESUMO

To overcome drug resistance caused by apoptosis deficiency in patients with non-small cell lung carcinoma (NSCLC), there is a need to identify other means of triggering apoptosis-independent cancer cell death. We are the first to report that isogambogenic acid (iso-GNA) can induce apoptosis-independent autophagic cell death in human NSCLC cells. Several features of the iso-GNA-treated NSCLC cells indicated that iso-GNA induced autophagic cell death. First, there was no evidence of apoptosis or cleaved caspase 3 accumulation and activation. Second, iso-GNA treatment induced the formation of autophagic vacuoles, increased LC3 conversion, caused the appearance of autophagosomes and increased the expression of autophagy-related proteins. These findings provide evidence that iso-GNA induces autophagy in NSCLC cells. Third, iso-GNA-induced cell death was inhibited by autophagic inhibitors or by selective ablation of Atg7 and Beclin 1 genes. Furthermore, the mTOR inhibitor rapamycin increased iso-GNA-induced cell death by enhancing autophagy. Finally, a xenograft model provided additional evidence that iso-GNA exhibited anticancer effect through inducing autophagy-dependent cell death in NSCLC cells. Taken together, our results demonstrated that iso-GNA exhibited an anticancer effect by inducing autophagy-dependent cell death in NSCLC cells, which may be an effective chemotherapeutic agent that can be used against NSCLC in a clinical setting.


Assuntos
Antineoplásicos/toxicidade , Autofagia/efeitos dos fármacos , Xantonas/toxicidade , Apoptose , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 7 Relacionada à Autofagia , Proteína Beclina-1 , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/toxicidade , Serina-Treonina Quinases TOR/metabolismo , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Enzimas Ativadoras de Ubiquitina/genética , Enzimas Ativadoras de Ubiquitina/metabolismo , Xantonas/química
14.
Molecules ; 18(12): 15305-13, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24335612

RESUMO

Eleven known caged polyprenylated xanthones 1-11 were isolated from the resin of Garcinia hanburyi Hook. f., and their structures were identified by their MS, NMR and UV spectra. These xanthones showed significant cytotoxicities against four human cancer cell lines (HeLa, A549, HCT-116, and HepG-2) and strong inhibition against the proliferation of the HUVEC cell line in vitro by the MTT method. Furthermore, in an in vivo zebrafish model, xanthones 3 (morellic acid), 7 (gambogenin) and 9 (isogambogenic acid) showed comparable antiangiogenic activities with less toxicities than xanthone 1 (gambogic acid), as evaluated by death and heart rates of treated zebrafish. Xanthone 7 exhibited antiangiogenic activity with no toxicity at concentrations ranging from 8 µM to 16 µM. Meanwhile, xanthones 1, 3, 7 and 9 strongly inhibited the migration of HUVEC at a low concentration of 0.5 µM in HUVEC cell migration assay in vitro. Taken together, these findings strongly suggest that xanthone 7 might be a novel angiogenesis inhibitor.


Assuntos
Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Garcinia/química , Xantonas/química , Xantonas/farmacologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Xantonas/isolamento & purificação , Peixe-Zebra
15.
J Chemother ; 25(5): 298-308, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24070138

RESUMO

Isogambogenic acid (iso-GNA) is a well-known herbal medicine extracted from Garcinia hanburyi. Although it is thought to have anti-tumour effects, its function is still unknown. This study carried out in vitro and in vivo evaluations of the anti-tumour and anti-angiogenic activity of iso-GNA and underlying mechanisms. A standard methyl thiazolyl tetrazolium assay showed that iso-GNA was more effective in inhibiting the proliferation of human umbilical vascular endothelial cells than A549 cancer cells. Iso-GNA demonstrated potent anti-angiogenic activity and low toxicity at appropriate concentrations in zebrafish embryos. In a xenograft nude mouse model of lung tumour, iso-GNA effectively inhibited tumour growth and tumour angiogenesis. Iso-GNA suppressed neovascularization of implanted matrigel plugs in vivo and inhibited vascular endothelial growth factor (VEGF)-induced microvessel sprouting from mouse aortic rings ex vivo. Iso-GNA inhibited VEGF-induced migration, invasion, and tube formation in vitro and affected cytoskeletal rearrangement in human umbilical vascular endothelial cells. The results show that iso-GNA suppressed angiogenesis-mediated tumour growth by targeting VEGFR2, Akt, mitogen-activated protein kinase, Rho GTPase, vascular endothelium-cadherin, and focal adhesion kinase signalling pathways. Together, these data suggest that iso-GNA inhibits angiogenesis and may be a viable drug candidate in anti-angiogenesis and anti-cancer therapies.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Extratos Vegetais/farmacologia , Terpenos/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Xantonas/farmacologia , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Animais , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Feminino , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Plantas Medicinais/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Xantenos , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
16.
Carcinogenesis ; 34(7): 1636-43, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23471882

RESUMO

In this study, we reported millepachine (MIL), a novel chalcone compound for the first time isolated from Millettia pachycarpa Benth (Leguminosae), induced cell cycle arrest and apoptosis in human hepatocarcinoma cells in vitro and in vivo. In in vitro screening experiments, MIL showed strong antiproliferation activity in several human cancer cell lines, especially in HepG2 cells with an IC50 of 1.51 µM. Therefore, we chose HepG2 and SK-HEP-1 cells to study MIL's antitumor mechanism. Flow cytometry showed that MIL induced a G2/M arrest and apoptosis in a dose-dependent manner. Western blot demonstrated that MIL-induced G2/M arrest was correlated with the inhibition of cyclin-dependent kinase 1 activity, including a remarkable decrease in cell division cycle (cdc) 2 synthesis, the accumulation of phosphorylated-Thr14 and decrease of phosphorylation at Thr161 of cdc2. This effect was associated with the downregulation of cdc25C and upmodulation of checkpoint kinase 2 in response to DNA damage. MIL also activated caspase 9 and caspase 3, and significantly increased the ratio of Bax/Bcl-2 and stimulated the release of cytochrome c into cytosol, suggesting MIL induced apoptosis via mitochondrial apoptotic pathway. Associated with those effects, MIL also induced the generation of reactive oxygen species. In HepG2 tumor-bearing mice models, MIL remarkably and dose dependently inhibited tumor growth. Treatment of mice with MIL (20mg/kg intravenous [i.v.]) caused more than 65% tumor inhibition without cardiac damage compared with 47.57% tumor reduction by 5mg/kg i.v. doxorubicin with significant cardiac damage. These effects suggested that MIL and its easily modified structural derivative might be a potential lead compound for antitumor drug.


Assuntos
Apoptose , Proteína Quinase CDC2/metabolismo , Carcinoma Hepatocelular/patologia , Chalconas/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular , Mitocôndrias/patologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Proteína Quinase CDC2/genética , Carcinoma Hepatocelular/metabolismo , Chalcona/farmacologia , Chalconas/química , Ciclina B/genética , Ciclina B/metabolismo , Quinases Ciclina-Dependentes , Citosol/metabolismo , Dano ao DNA , Relação Dose-Resposta a Droga , Ativação Enzimática , Feminino , Citometria de Fluxo , Células Hep G2 , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/patologia , Potenciais da Membrana , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Millettia/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Fitoterapia ; 83(8): 1402-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22902267

RESUMO

The aim of this study is to investigate the cytotoxic and apoptotic effects of constituents from the seeds of Millettia pachycarpa Benth. Fourteen compounds (1-14) including one novel chalcone (10) were isolated as active principles from Chinese herbal medicine M. pachycarpa Benth. Their structures were identified by using spectroscopic methods. All isolates were then evaluated for their cytotoxic effects against several cancer cell lines (HepG2, C26, LL2 and B16) with cisplatin as a positive control. And their apoptosis-inducing effects were tested against HeLa-C3 cells with taxol as a positive control. Both studies showed that compounds 1, 2, 7 and 10 demonstrated significant cytotoxic and apoptotic effects against cancer cells. Moreover, in the apoptosis assay the novel chalcone (10) showed strong apoptosis inducing effects at a concentration of 2µM within 36h. It was found to be the most potent apoptotic inducer of the compounds isolated from M. pachycarpa Benth.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Millettia/química , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Estrutura Molecular
18.
Molecules ; 17(6): 6249-68, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22634837

RESUMO

Gambogic acid (GA) is in a phase II clinical trial as an antitumor and antiangiogenesis agent. In this study, 36 GA derivatives were synthesized and screened in a zebrafish model to evaluate their antiangiogenic activity and toxicity. Derivatives 4, 32, 35, 36 effectively suppressed the formation of newly grown blood vessels and showed lower toxicities than GA as evaluated by zebrafish heart rates and mortalities. They also exhibited more potent migration and HUVEC tube formation inhibiting activities than GA. Among them, 36 was the most potent one, suggesting that it may serve as a potential new antiangiogenesis candidate with low toxicity. Additionally, 36 showed comparable antiproliferative activity to HUVECs and five tumor cell lines but low cytotoxicity to LO2 cells.


Assuntos
Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/farmacologia , Xantonas/síntese química , Xantonas/farmacologia , Inibidores da Angiogênese/química , Animais , Animais Geneticamente Modificados , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Concentração Inibidora 50 , Neovascularização Fisiológica/efeitos dos fármacos , Relação Estrutura-Atividade , Xantonas/química , Peixe-Zebra
19.
J Chromatogr A ; 1235: 34-8, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22424731

RESUMO

In general, simultaneously separation and purification of components with a broad polarity range from traditional Chinese medicine (TCM) is a challenge by an ordinary high-speed counter-current chromatography (HSCCC) method. In this paper, we describes a rapid and efficient separation method of combining three-step gradient elution and two-step flow-rate gradient elution using high-performance counter-current chromatography (HPCCC) to separate 8 diterpene compounds simultaneously within 80 min in a single run from the alcohol extract of Pseudolarix kaempferi Gordon. This separation process produced 166 mg pseudolaric acid B O-ß-d-glucopyranoside (PABGly), 152 mg pseudolaric acid C (PAC), 8 mg deacetylpseudolaric acid A (deacetylPAA), 5 mg pseudolaric acid A O-ß-d-glucopyranoside (PAAGly), 484 mg pseudolaric acid B (PAB), 33 mg pseudolaric acid B methyl ester (PAB methyl ester), 10mg pseudolaric acid A (PAA) and 18 mg pseudolaric acid H (PAH) from 1.0 g crude sample with purities of 98.6%, 99.6%, 92.3%, 92.2%, 99.2%, 99.4%, 98.3%, 91.0%, respectively. Our study indicates that the suitable combination of step-wise gradient elution and flow-rate gradient elution using HPCCC is an effective strategy to separate complex components from natural products.


Assuntos
Distribuição Contracorrente/métodos , Diterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Pinaceae/química , Distribuição Contracorrente/economia , Fatores de Tempo
20.
J Sep Sci ; 35(2): 256-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25939902

RESUMO

Recycling counter-current chromatography (CCC) together with step-gradient CCC and medium-pressure liquid chromatography (MPLC) was employed to separate nine anthraquinone compounds from Cassia obtusifolia L. in this study. The results showed that recycling CCC is a powerful tool for compounds that are difficult to separate with common elution mode. CCC was the better option for crude material while MPLC had advantage for the final tuning. The combination of recycling CCC and MPLC could simplify the method exploring process in the separation process. The structures of these compounds were identified according to their mass spectra, by (1)H-NMR and compared with standard compounds.


Assuntos
Antraquinonas/isolamento & purificação , Cassia/química , Distribuição Contracorrente/métodos , Antraquinonas/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Plantas Medicinais/química , Sementes/química , Solventes , Espectrometria de Massas por Ionização por Electrospray
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