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1.
Bioresour Technol ; 413: 131451, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39244108

RESUMO

The aim of this study was to investigate the effects of various concentrations of antioxidants, including butyl hydroxy anisd (BHA), butylated hydroxytoluene (BHT), fulvic acid (FA), melatonin (MT), glycine betaine (GB) and putrescine (Put), on growth and lipid synthesis of microalgae under low-temperature (15 ℃). Changes in biochemical indicators, reactive oxygen species (ROS) level, glutathione (GSH) content and antioxidant enzyme activities were also studied. The results indicated that the maximum biomass concentration (1.3 g/L) and lipid productivity (75.3 ± 5.8 mg/L d-1) were achieved under 100 µM MT and 1 µM GB, respectively. Moreover, antioxidants were able to increase the GSH and antioxidant enzymes activities in algal cells under low-temperature stress. This study was enlightening for the utilization of antioxidants to improve the resistance to low-temperature stress and lipid production in microalgae, and provided a theoretical basis for the application of microalgae for lipid accumulation in cold regions.


Assuntos
Antioxidantes , Temperatura Baixa , Microalgas , Espécies Reativas de Oxigênio , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lipídeos/biossíntese , Biomassa , Estresse Fisiológico/efeitos dos fármacos , Glutationa/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos
2.
J Hazard Mater ; 480: 135831, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39303609

RESUMO

Heavy metal pollution in the cold region is serious, affecting human health and aquatic ecology. This study investigated the ability of microalgae to remove heavy metals (HMs) and produce lipid at low temperature. The removal efficiency of different HMs (Cd2+, Cu2+, Cr3+ and Pb2+), cell growth and lipid synthesis of microalgae were analyzed at 15 °C. Moreover, addition of glycine betaine (GB) further enhanced the productivity of microalgae in treating HMs and lipid production, and simultaneously increased the antioxidant capacity of microalgae against environmental stresses. The results showed that the highest lipid productivity of 100.98 mg L-1 d-1 and the removal efficiency of 85.8 % were obtained under GB coupled with Cr3+. The highest glutathione content of 670.34 nmol g-1 fresh alga was achieved under GB coupled with Pb2+. In addition, lipidomics showed that GB was able to up-regulate the triglyceride and diglyceride content, influenced fatty acid composition to regulate the microalgal metabolism, and mediated lipid accumulation under 15 °C mainly through the regulation of glycerol ester metabolism. This study provided a new perspective on microalgal lipid production and the removal of HMs in cold regions and provided evidence for the use of phytohormones to improve the algal environmental resistance.

3.
Environ Sci Ecotechnol ; 21: 100420, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38765891

RESUMO

Chlorinated organic pollutants constitute a significant category of persistent organic pollutants due to their widespread presence in the environment, which is primarily attributed to the expansion of agricultural and industrial activities. These pollutants are characterized by their persistence, potent toxicity, and capability for long-range dispersion, emphasizing the importance of their eradication to mitigate environmental pollution. While conventional methods for removing chlorinated organic pollutants encompass advanced oxidation, catalytic oxidation, and bioremediation, the utilization of biochar has emerged as a prominent green and efficacious method in recent years. Here we review biochar's role in remediating typical chlorinated organics, including polychlorinated biphenyls (PCBs), triclosan (TCS), trichloroethene (TCE), tetrachloroethylene (PCE), organochlorine pesticides (OCPs), and chlorobenzenes (CBs). We focus on the impact of biochar material properties on the adsorption mechanisms of chlorinated organics. This review highlights the use of biochar as a sustainable and eco-friendly method for removing chlorinated organic pollutants, especially when combined with biological or chemical strategies. Biochar facilitates electron transfer efficiency between microorganisms, promoting the growth of dechlorinating bacteria and mitigating the toxicity of chlorinated organics through adsorption. Furthermore, biochar can activate processes such as advanced oxidation or nano zero-valent iron, generating free radicals to decompose chlorinated organic compounds. We observe a broader application of biochar and bioprocesses for treating chlorinated organic pollutants in soil, reducing environmental impacts. Conversely, for water-based pollutants, integrating biochar with chemical methods proved more effective, leading to superior purification results. This review contributes to the theoretical and practical application of biochar for removing environmental chlorinated organic pollutants.

4.
Eur J Med Chem ; 268: 116277, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38422700

RESUMO

A series of novel urea derivatives were designed, synthesized and evaluated for their inhibitory activities against HT-29 cells, and structure-activity relationships (SAR) were summarized. Compound 10p stood out from these derivatives, exhibiting the most potent antiproliferative activity. Further biological studies demonstrated that 10p arrested cell cycle at G2/M phase via regulating cell cycle-related proteins CDK1 and Cyclin B1. The underlying molecular mechanisms demonstrated that 10p induced cell death through ferroptosis and autophagy, but not apoptosis. Moreover, 10p-induced ferroptosis and autophagy were both related with accumulation of ROS, but they were independent of each other. Our findings substantiated that 10p combines ferroptosis induction and autophagy trigger in single molecule, making it a potential candidate for colon cancer treatment and is worth further development.


Assuntos
Neoplasias do Colo , Ferroptose , Humanos , Divisão Celular , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Autofagia , Neoplasias do Colo/tratamento farmacológico , Linhagem Celular Tumoral
5.
Water Res ; 251: 121120, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38237459

RESUMO

Waste activated sludge (WAS) as one of the major pollutants with a significant annual production, has garnered significant attention regarding its treatment and utilization. If improperly discharged, it not only caused environmental pollution but also led to the wastage of valuable resources. In this study, the microalgae growth and lipid accumulation using waste activated sludge extracts (WASE) under different temperature conditions were investigated. The highest lipid content (59.13%) and lipid productivity (80.41 mg L-1 d-1) were obtained at cultivation temperatures of 10 and 25 °C, respectively. It was found that microalgae can effectively utilize TN/TP/NH4+-N and other nutrients of WASE. The highest utilization rates of TP, TN and NH4+-N were achieved at a cultivation temperature of 10 °C, reaching 84.97, 77.49 and 92.32%, respectively. The algal fatty acids had carbon chains predominantly ranging from C14 to C18, making them suitable for biodiesel production. Additionally, a comprehensive analysis of transcriptomics and metabolomics revealed up-regulation of genes associated with triglyceride assembly, the antioxidant system of algal cells, and cellular autophagy, as well as the accumulation of metabolites related to the tricarboxylic acid (TCA) cycle and lipids. This study offers novel insights into the microscopic mechanisms of microalgae culture using WASE and approaches for the resource utilization of sludge.


Assuntos
Microalgas , Esgotos , Lipídeos , Biocombustíveis , Temperatura , Perfilação da Expressão Gênica , Biomassa
6.
Water Res ; 251: 121134, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244297

RESUMO

A coupling technology for lipid production and adsorption of rare earth elements (REEs) using microalgae was studied in this work. The microalgae cell growth, lipid production, biochemical parameters and lipid profiles were investigated under different REEs (Ce3+, Gd3+and La3+). The results showed that the maximum lipid production was achieved at different concentrations of REEs, with lipid productivities of 300.44, 386.84 and 292.19 mg L-1 d-1 under treatment conditions of 100 µg L-1 Ce3+, 250 µg L-1 Gd3+ and 1 mg L-1 La3+, respectively. Moreover, the adsorption efficiency of Ce3+, Gd3+ and La3+exceeded 96.58 %, 93.06 % and 91.3 % at concentrations of 25-1000 µg L-1, 100-500 µg L-1 and 0.25-1 mg L-1, respectively. In addition, algal cells were able to adsorb 66.2 % of 100 µg L-1 Ce3+, 48.4 % of 250 µg L-1 Gd3+ and 59.9 % of 1 mg L-1 La3+. The combination of extracellular polysaccharide and algal cell wall could adsorb 25.2 % of 100 µg L-1 Ce3+, 44.5 % of 250 µg L-1 Gd3+ and 30.5 % of 1 mg L-1 La3+, respectively. These findings indicated that microalgae predominantly adsorbed REEs through the intracellular pathway. This study elucidates the mechanism of effective lipid accumulation and adsorption of REEs by microalgae under REEs stress conditions. It establishes a theoretical foundation for the efficient microalgae lipid production and REEs recovery from wastewater or waste residues containing REEs.


Assuntos
Metais Terras Raras , Microalgas , Biocombustíveis , Adsorção , Lipídeos
7.
RSC Adv ; 13(43): 30202-30216, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37849704

RESUMO

Colchicine binding site inhibitors (CBSIs) are potential microtubule targeting agents (MTAs), which can overcome multidrug resistance, improve aqueous solubility and reduce toxicity faced by most MTAs. Novel tetrahydroquinoxaline sulfonamide derivatives were designed, synthesized and evaluated for their antiproliferative activities. The MTT assay results demonstrated that some derivatives exhibited moderate to strong inhibitory activities against HT-29 cell line. Among them, compound I-7 was the most active compound. Moreover, I-7 inhibited tubulin polymerization, disturbed microtubule network, disrupted the formation of mitotic spindle and arrested cell cycle at G2/M phase. However, I-7 didn't induce cell apoptosis. Furthermore, the prediction of ADME demonstrated that I-7 showed favorable physiochemical and pharmacokinetic properties. And the detailed molecular docking confirmed I-7 targeted the site of colchicine through hydrogen and hydrophobic interactions.

8.
Water Res ; 239: 120027, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37167853

RESUMO

Thallium (Tl+) is a trace metal with extreme toxicity and is highly soluble in water, posing a great risk to ecological and human safety. This work aimed to investigate the role played by Tl+ in regulating lipid accumulation in microalgae and the removal efficiency of Tl+. The effect of Tl+ on the cell growth, lipid production and Tl+ removal efficiency of Parachlorella kessleri R-3 was studied. Low concentrations of Tl+ had no significant effect on the biomass of microalgae. When the Tl+ concentration exceeded 5 µg L-1, the biomass of microalgae showed significant decrease. The highest lipid content of 63.65% and lipid productivity of 334.55 mg L-1 d-1 were obtained in microalgae treated with 10 and 5 µg L-1 Tl+, respectively. Microalgae can efficiently remove Tl+ and the Tl+ removal efficiency can reach 100% at Tl+ concentrations of 0-25 µg L-1. The maximum nitric oxide (NO) level of 470.48 fluorescence intensity (1 × 106 cells)-1 and glutathione (GSH) content of 343.51 nmol g-1 (fresh alga) were obtained under 5 µg L-1 Tl+ stress conditions. Furthermore, the exogenous donor sodium nitroprusside (SNP) supplemented with NO was induced in microalgae to obtain a high lipid content (59.99%), lipid productivity (397.99 mg L-1 d-1) and GSH content (430.22 nmol g-1 (fresh alga)). The corresponding analysis results indicated that NO could participate in the signal transduction pathway through modulation of reactive oxygen species (ROS) signaling to activate the antioxidant system by increasing the GSH content to eliminate oxidative damage induced by Tl+ stress. In addition, NO regulation of ROS signaling may enhance transcription factors associated with lipid synthesis, which stimulates the expression of genes related to lipid synthesis, leading to increased lipid biosynthesis in microalgae. Moreover, it was found that the change in Tl+ had little effect on the fatty acid components and biodiesel properties. This study showed that Tl+ stress can promote lipid accumulation in microalgae for biodiesel production and simultaneously effectively remove Tl+, which provided evidence that NO was involved in signal transduction and antioxidant defense, and improved the understanding of the interrelation between NO and ROS to regulate lipid accumulation in microalgae.


Assuntos
Metais Pesados , Microalgas , Humanos , Tálio/metabolismo , Antioxidantes , Espécies Reativas de Oxigênio/metabolismo , Biodegradação Ambiental , Biocombustíveis , Glutationa , Lipídeos , Transdução de Sinais , Biomassa
9.
Environ Sci Pollut Res Int ; 30(16): 48339-48350, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36757593

RESUMO

In this study, a new microalgal strain, Asterarcys quadricellulare R-56, was isolated for biomass and lipid production. The effects of carbon and nitrogen sources and initial pH on the cell growth and lipid accumulation of strain R-56 were investigated. At 10 g L-1 glucose, 0.6 g L-1 sodium nitrate, and pH 7, the highest biomass of 4.18 g L-1 and lipid content of 43.66% were obtained. Microalgae had a broad pH tolerance in the range of 5-11, and the pH of the culture medium was close to neutral at the end of cultivation. The maximum contents of chlorophyll, carbohydrate, and protein under the recommended culture conditions were 19.47 mg mL-1, 21.80%, and 29.94%, respectively. Palmitic and palmitoleic acid contents in strain R-56 accounted for as high as 83.73% of total fatty acids. This study suggested that strain R-56 was a promising lipid producer for high-quality biodiesel production.


Assuntos
Clorofíceas , Microalgas , Biocombustíveis , Ácidos Graxos/metabolismo , Carboidratos , Proteínas/metabolismo , Biomassa
10.
Bioresour Technol ; 370: 128515, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36538957

RESUMO

Microalgae have become the hotspot of recent researches as heavy metals (HMs) adsorbent and biodiesel production feedstock. In this study, the cell growth, lipid production and Cr6+ removal of Parachlorella kessleri R-3 at pH 3.5 and 15 °C were investigated. It was found that low concentration of Cr6+ (0.5 to 2 mg/L) promoted the algal growth, whereas Cr6+ higher than 5 mg/L inhibited the growth of P. kessleri R-3. Biomass concentration (2.40 g/L) and lipid productivity (131.79 mg/L d-1) reached the highest at 2 mg/L Cr6+, and lipid content (61.03 %) reached the highest at 5 mg/L Cr6+. The maximum Cr6+ removal efficiency of 91 % was obtained at 0.5 mg/L Cr6+ treatment. Furthermore, fatty acid composition analysis showed that strain R-3 had a high C16-18 content of 74.88-89.21 %. This study provides new insight into the treatment of HMs and lipid production in cold regions.


Assuntos
Metais Pesados , Microalgas , Cromo , Biocombustíveis , Temperatura , Ácidos Graxos , Ácidos , Biomassa
11.
Biochim Biophys Acta Rev Cancer ; 1877(5): 188777, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35963551

RESUMO

Microtubule targeting agents (MTAs) have attracted extensive attention for cancer treatment. However, their clinical efficacies are limited by intolerable toxicities, inadequate efficacy and acquired multidrug resistance. The combination of MTAs with other antineoplastics has become an efficient strategy to lower the toxicities, overcome resistance and improve the efficacies for cancer treatment. In this article, we review the combinations of MTAs with some other anticancer drugs, such as cytotoxic agents, kinases inhibitors, histone deacetylase inhibitors, immune checkpoints inhibitors, to overcome these obstacles. We strongly believe that this review will provide helpful information for combination therapy based on MTAs.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Citotoxinas/farmacologia , Citotoxinas/uso terapêutico , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Microtúbulos , Neoplasias/tratamento farmacológico
12.
Bioresour Technol ; 306: 123107, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32172089

RESUMO

The roles of jasmonic acid (JA) in the regulation of cell growth and lipid biosynthesis under the combination of strigolactone (SL) treatment and nitrogen deficiency (ND) were investigated. In this work, the optimised ND condition (46.18%) and ND combined with SL treatment (53.71%) showed 1.11- and 1.29-fold increases in lipid content in Monoraphidium sp. QLY-1 compared with the control condition (41.57%). The levels of JA, glutathione (GSH), and γ-aminobutyric acid (GABA) and lipogenic genes expression were upregulated by the combination of SL and ND, but the ROS level was decreased. Furthermore, exogenous JA supplementation induced the highest lipid content (57.12%) and productivity (312.35 mg L-1 d-1) under ND combined with SL treatment. This study provided a combined strategy for enhancing lipid production and supplied novel insights into the role of JA signalling in regulating lipid synthesis and oxidative stress in microalgae by combining SL treatment with ND.

13.
Bioresour Technol ; 297: 122500, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31796380

RESUMO

This study explored the effects of γ-aminobutyric acid (GABA) on the production of biomass and lipids and on the uptake of Cd2+ by microalgae under cadmium (Cd) stress. Compared with the control and Cd stress alone, 2.5 mM GABA increased the maximum lipid content (55.37%) by 49.37% and 9.42%, respectively. GABA application resulted in increased contents of protein and glutathione (GSH) and in upregulated activity of α-amylase but decreased contents of starch, reactive oxygen species (ROS) and Cd2+, with no effect on subsequent biodiesel quality. Additional analysis of GABA further indicated that increased cellular GABA contents could promote lipid synthesis and reduce Cd accumulation by regulating the expression levels of lipogenesis genes, ROS signalling and mineral nutrient uptake under Cd stress. Collectively, these findings show that GABA not only increases lipid production in microalgae but also is involved in the mechanisms by which microalgae respond to Cd stress.


Assuntos
Cádmio , Microalgas , Biomassa , Lipídeos , Ácido gama-Aminobutírico
14.
Bioresour Technol ; 288: 121607, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31176945

RESUMO

In this study, the effects of strigolactone (SL) on the biomass, lipid content, biochemical properties, and gene transcription of Monoraphidium sp. QLY-1 were examined. The lipid content and lipid productivity increased by 61% and 55% in QLY-1 under 1 µM SL induction compared to the control group, respectively. SL also upregulated the levels of endogenous NO and Ca2+ and lipid biosynthesis gene transcription. Subsequently, the relationship between Ca2+ and nitric oxide (NO) in the regulation of cell growth and lipid accumulation of QLY-1 under SL induction conditions was analysed. An increase in endogenous Ca2+ regulated cell growth and lipid biosynthesis by modulating the levels of NO and lipid biosynthesis-related gene expression. Collectively, this study provided a valuable approach for biofuel production from microalgae under SL induction and demonstrated that there is crucial crosstalk between the Ca2+ and NO signalling in the manipulation of lipid biosynthesis in microalgae under SL treatment.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Clorofíceas , Lipídeos
15.
Molecules ; 21(6)2016 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-27314315

RESUMO

Incubation systems were established to investigate the effects of quercetin, kaempferol, isoquercitrin and astragalin in Lysimachia clethroides Duby on the activities of CYP2E1 and CYP3A4 in rat liver microsomes in vitro. Probe substrates of 4-nitrophenol and testosterone as well as flavonoids at different concentrations were added to the incubation systems. After incubation, a validated high performance liquid chromatography (HPLC) method was applied to separate and determine the relevant metabolites. The results suggested that kaempferol exhibited a weak inhibition of CYP2E1 activity with an IC50 of 60.26 ± 2.54 µM, while quercetin and kaempferol caused a moderate inhibition of CYP3A4 activity with IC50 values of 18.77 ± 1.69 µM and 32.65 ± 1.32 µM, respectively. Isoquercitrin and astragalin had no effects on the activities of either CYP2E1 or CYP3A4. It could be speculated from these results that the inhibitory effects of quercetin and kaempferol on the activities of CYP2E1 and CYP3A4 could be the mechanisms underlying the hepatoprotective effects of L. clethroides.


Assuntos
Citocromo P-450 CYP2E1/biossíntese , Citocromo P-450 CYP3A/biossíntese , Microssomos Hepáticos/efeitos dos fármacos , Animais , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Flavonoides/administração & dosagem , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Quempferóis/administração & dosagem , Microssomos Hepáticos/enzimologia , Primulaceae/química , Quercetina/administração & dosagem , Quercetina/análogos & derivados , Ratos
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