Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Bioresour Technol ; 372: 128651, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682476

RESUMO

This study was conducted to increase the productivity of biomass that contains high astaxanthin content by developing a mutant Haematococcus pluvialis strain with strong environmental tolerance. H. pluvialis has a low cell-growth rate and is vulnerable to stressors such as salinity or light intensity, which may hinder large-scale commercial cultivation. A mutant M5 strain selected through 5000-Gy gamma irradiation showed improved biomass and astaxanthin production under high-salinity and high-light intensity conditions. With enhanced SOD activity and overexpressed astaxanthin biosynthesis genes (lyc, crtR-b, bkt2), M5 demonstrated an increase in biomass and astaxanthin productivity by 86.70 % and 66.15 %, respectively compared to those of untreated cells. Also, the omega-3 content of M5 increased by 149.44 % under 40 mM CaCl2 compared to the untreated cells. Finally, even when subjected to high-intensity light irradiation for the whole life cycle, the biomass and astaxanthin concentration increased by 84.99 % and 241 %, respectively, compared to the wild-type cells.


Assuntos
Clorofíceas , Luz , Xantofilas , Cloreto de Sódio , Biomassa
2.
Bioresour Technol ; 364: 128134, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36252755

RESUMO

Hydrogen as a clean fuel is receiving attention because it generates only water and a small amount of nitrogen oxide upon combustion. Biohydrogen production using microalgae is considered to be a highly promising carbon-neutral technology because it can secure renewable energy while efficiently reducing CO2 emissions. However, previous studies have mainly focused on improving the biological performance of microalgae; these approaches have struggled to achieve breakthroughs in commercialization because they do not heavily consider the complexity of the entire production process with microalgae, including large-scale cultivation, biomass harvest, and biomass storage. This work presents an in-depth analysis of the state-of-the-art technologies focused on large-scale cultivation systems with efficient downstream processes. Considering the individual processes of biohydrogen production, strategies are discussed to minimize carbon emissions and improve productivity simultaneously. A comprehensive understanding of microalgae-derived biohydrogen production suggests future directions for realizing environmental and economic sustainability.

3.
Bioresour Technol ; 364: 128063, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36195219

RESUMO

In this study, the effects of microalgae-based biomineralization in a semi-continuous process (M-BSP) on biomass productivity and CO2 fixation rate were investigated. M-BSP significantly improved biomass production and CO2 fixation rate at the second stage of induction by sustaining relatively high photosynthetic rate without exposure to toxic substances (e.g., chlorellin) from aging cells using the microalgae Chlorella HS2. In conventional systems, cells do not receive irradiated light evenly, and many cells age and burst because of the long culture period. In contrast, in the M-BSP, the photosynthesis efficiency increases and biomass production is not inhibited because most of the cells can be harvested during shorter culture period. The accumulated biomass production and CO2 fixation rate of the HS2 cells cultured under M-BSP increased by 4.67- (25 ± 1.09 g/L) and 10.9-fold (30.29 ± 1.79 g/L day-1), respectively, compared to those cultured without the CaCl2 treatment.


Assuntos
Chlorella , Microalgas , Dióxido de Carbono , Biomineralização , Fotossíntese , Biomassa
4.
Mol Nutr Food Res ; 61(10)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28544341

RESUMO

SCOPE: Recent reports indicate that gut microbiota and their metabolites may regulate host inflammatory conditions, including the chronic inflammation of obese adipose tissues. In this study, we investigated whether specific synthesized fatty acids, identical to the metabolites generated by gut microbiota, act as anti-inflammatory factors in obesity-induced inflammation. METHODS AND RESULTS: We first used lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages to examine the anti-inflammatory effect of fatty acids synthesized to resemble representative polyunsaturated fatty acid metabolites from gut microbiota. Fatty acids containing an enone structure showed the most potent anti-inflammatory activity. Enone fatty acids also displayed anti-inflammatory effects on macrophages cocultured with hypertrophied 3T3-L1 or immortalized primary adipocytes; and macrophages stimulated with 3T3-L1 adipocyte conditioned medium. Consistently, the beneficial outcome was revealed in the case of LPS- and obesity-induced inflammatory cytokine stimulation in ex vivo adipose tissues. Furthermore, these fatty acids recovered the suppression of ß-adrenergic receptor-stimulated uncoupling protein 1 expression and secretion of adiponectin in C3H10T1/2 and 3T3-L1 adipocytes, respectively, under inflammatory conditions, suggesting that enone fatty acids can ameliorate dysfunctions of adipocytes induced by inflammation. CONCLUSION: These findings indicate that synthesized enone fatty acids show potent anti-inflammatory effects, leading to the improvement of inflammation-induced dysfunctions in adipocytes.


Assuntos
Adipócitos/citologia , Anti-Inflamatórios/farmacologia , Ácidos Graxos Insaturados/farmacologia , Microbioma Gastrointestinal , Inflamação/terapia , Macrófagos/citologia , Células 3T3-L1 , Adiponectina/metabolismo , Animais , Quimiocina CCL2/metabolismo , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Lactobacillus/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Obesidade/terapia , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
5.
Biochem Biophys Res Commun ; 459(4): 597-603, 2015 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-25749343

RESUMO

Our previous study has shown that gut lactic acid bacteria generate various kinds of fatty acids from polyunsaturated fatty acids such as linoleic acid (LA). In this study, we investigated the effects of LA and LA-derived fatty acids on the activation of peroxisome proliferator-activated receptors (PPARs) which regulate whole-body energy metabolism. None of the fatty acids activated PPARδ, whereas almost all activated PPARα in luciferase assays. Two fatty acids potently activated PPARγ, a master regulator of adipocyte differentiation, with 10-oxo-12(Z)-octadecenoic acid (KetoA) having the most potency. In 3T3-L1 cells, KetoA induced adipocyte differentiation via the activation of PPARγ, and increased adiponectin production and insulin-stimulated glucose uptake. These findings suggest that fatty acids, including KetoA, generated in gut by lactic acid bacteria may be involved in the regulation of host energy metabolism.


Assuntos
Adipogenia/efeitos dos fármacos , Lactobacillus/metabolismo , Ácidos Linoleicos/biossíntese , PPAR gama/metabolismo , Animais , Metabolismo Energético , Ácidos Linoleicos/farmacologia , Camundongos , Células NIH 3T3 , Reação em Cadeia da Polimerase
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...