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1.
Sci Rep ; 12(1): 18813, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335189

RESUMO

N-7 methylguanine (m7G) is one of the most common RNA base modifications in post-transcriptional regulation, which participates in multiple processes such as transcription, mRNA splicing and translation during the mRNA life cycle. However, its expression and prognostic value in uterine corpus endometrial carcinoma (UCEC) have not been systematically studied. In this paper, the data such as gene expression profiles, clinical data of UCEC patients, somatic mutations and copy number variants (CNVs) are obtained from the cancer genome atlas (TCGA) and UCSC Xena. By analyzing the expression differences of m7G-related mRNA in UCEC and plotting the correlation network maps, a risk score model composed of four m7G-related mRNAs (NSUN2, NUDT3, LARP1 and NCBP3) is constructed using least absolute shrinkage and selection operator (LASSO), univariate and multivariate Cox regression in order to identify prognosis and immune response. The correlation of clinical prognosis is analyzed between the m7G-related mRNA and UCEC via Kaplan-Meier method, receiver operating characteristic (ROC) curve, principal component analysis (PCA), t-SNE, decision curve analysis (DCA) curve and nomogram etc. It is concluded that the high risk is significantly correlated with (P < 0.001) the poorer overall survival (OS) in patients with UCEC. It is one of the independent risk factors affecting the OS. Differentially expressed genes are identified by R software in the high and low risk groups. The functional analysis and pathway enrichment analysis have been performed. Single sample gene set enrichment analysis (ssGSEA), immune checkpoints, m6A-related genes, tumor mutation burden (TMB), stem cell correlation, tumor immune dysfunction and rejection (TIDE) scores and drug sensitivity are also used to study the risk model. In addition, we have obtained 3 genotypes based on consensus clustering, which are significantly related to (P < 0.001) the OS and progression-free survival (PFS). The deconvolution algorithm (CIBERSORT) is applied to calculate the proportion of 22 tumor infiltrating immune cells (TIC) in UCEC patients and the estimation algorithm (ESTIMATE) is applied to work out the number of immune and matrix components. In summary, m7G-related mRNA may become a potential biomarker for UCEC prognosis, which may promote UCEC occurrence and development by regulating cell cycles and immune cell infiltration. It is expected to become a potential therapeutic target of UECE.


Assuntos
Carcinoma Endometrioide , Neoplasias do Endométrio , Feminino , Humanos , Prognóstico , Neoplasias do Endométrio/patologia , Regulação Neoplásica da Expressão Gênica , Carcinoma Endometrioide/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Sci Rep ; 12(1): 16773, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202899

RESUMO

Necroptosis is a kind of programmed necrosis mode that plays a double-edged role in tumor progression. However, the role of necroptosis-related Messenger RNA (mRNA) in predicting the prognosis and immune response of cervical squamous carcinoma and adenocarcinoma (CESC) has not been fully studied. Firstly, the incidence of somatic mutation rate and copy number variation for 74 necroptosis-related mRNAs (NRmRNAs) were analyzed. Secondly, CESC patients were divided into four stable clusters based on the consensus clustering results and analyzed for correlations with a series of clinical factors. Subsequently, a total of 291 The Cancer Genome Atlas samples were randomly divided into either training or validation cohorts. A Cox proportional hazard model consisting of three NRmRNAs (CXCL8, CLEC9A, and TAB2) was constructed by univariate, least absolute shrinkage and selection operator and multivariate COX regression analysis to identify the prognosis and immune response. Its performance and stability were further validated in another testing dataset (GSE44001) from Gene Expression Omnibus database. The results of the receiver operating characteristic curve, principal component analysis, t-SNE, and nomogram indicated that the prognostic model we constructed can serve as an independent prognostic factor. The combination of the prognostic model and the classic TNM staging system could improve the performance in predicting the survival of CESC patients. In addition, differentially expressed genes from high and low-risk patients are screened by R software for functional analysis and pathway enrichment analysis. Besides, single-sample gene set enrichment analysis revealed that tumor-killing immune cells were reduced in the high-risk group. Moreover, patients in the low-risk group are more likely to benefit from immune checkpoint inhibitors. The analysis of tumor immune dysfunction and exclusion scores, M6A-related genes, stem cell correlation and Tumor mutational burden data with clinical information has quantified the expression levels of NRmRNAs between the two risk subgroups. According to tumor immune microenvironment scores, Spearman's correlation analysis, and drug sensitivity, immunotherapy may have a higher response rate and better efficacy in patients of the low-risk subgroup. In conclusion, we have reported the clinical significance of NRmRNAs for the prognosis and immune response in CESC patients for the first time. Screening of accurate and effective prognostic markers is important for designing a multi-combined targeted therapeutic strategy and the development of individualized precision medicine.


Assuntos
Adenocarcinoma , Neoplasias Ósseas , Neoplasias da Mama , Carcinoma de Células Escamosas , Neoplasias do Colo do Útero , Carcinoma de Células Escamosas/genética , Variações do Número de Cópias de DNA , Feminino , Humanos , Inibidores de Checkpoint Imunológico , Necroptose , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Microambiente Tumoral/genética , Neoplasias do Colo do Útero/genética
3.
Sci Rep ; 12(1): 16285, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-36175606

RESUMO

Necroptosis, a programmed form of necrotic cell death, plays critical regulatory roles in the progression and metastatic spread of cancers such as cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC). However, there are few articles systematically analyzing the necroptosis-related long non-coding RNAs (NRlncRNAs) correlated with CESC patients. Both RNA-sequencing and clinical data of CESC patients are downloaded from TCGA database in this study. Pearson correlation analysis, least absolute shrinkage, operator algorithm selection and Cox regression model are employed to screen and create a risk score model of eleven-NRlncRNAs (MIR100HG, LINC00996, SNHG30, LINC02688, HCG15, TUBA3FP, MIAT, DBH-AS1, ERICH6-AS1SCAT1, LINC01702) prognostic. Thereafter, a series of tests are carried out in sequence to evaluate the model for independent prognostic value. Gene set enrichment analytic paper, Gene Ontology analysis, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analytic paper make it clear that immune-related signaling pathways are very rich in the high-risk subgroup. Additionally, the prognostic risk score model is correlated to immune cell infiltration, potential immune checkpoint, immune function, immune micro-environmental and m6A-related gene. Mutation frequency in mutated genes and survival probability trend are higher in the low-risk subgroup in most of test cases when compared to the high-risk subgroup. This study constructs a renewed prognostic model of eleven-NRlncRNAs, which may make some contribution to accurately predicting the prognosis and the immune response from CESC patients, and improve the recognition of CESC patients and optimize customized treatment regimens to some extent.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , RNA Longo não Codificante , Neoplasias do Colo do Útero , Feminino , Humanos , Carcinoma de Células Escamosas/genética , Imunidade , Necroptose/genética , Prognóstico , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética
5.
Harmful Algae ; 96: 101842, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32560840

RESUMO

Lots of research has demonstrated that macroalgae can strongly inhibit the growth of harmful algal bloom (HAB) species in general. However, the effects of HABs or HAB-forming species on macrophytes are still largely uncharacterized until now. In the present study, the effects of the dinoflagellate Karenia mikimotoi cell density gradient, live cell suspension (LC), ruptured cell suspension (RC) as well as the cell-free supernatant (FC) of K. mikimotoi at 1000 µg Chla l-1 (~1.0 × 105 cells ml-1) on the development and photosynthesis of Sargassum fusiforme embryos were investigated in a series of laboratory experiments. The results showed that co-cultivation with K. mikimotoi at 500 µg Chla l-1(~5.0 × 104 cells ml-1) and higher cell densities significantly (P<0.05) inhibited the development, pigment content and photosynthetic activities of the embryos. In addition, the inhibitory effects increased with increased cell densities and prolonged exposure time. Compared to the embryos cultured with the F/2 medium (Control), exposure to LC, RC and FC of K. mikimotoi at 1000 µg Chla l-1for 2 weeks all led to decreased relative growth rate (RGR), chlorophyll (Chl) a content, carotenoids (Car) content and photosynthetic activities of the embryos, with LC and RC exhibiting the maximal and the minimal suppression. The dominant inhibitory effects of FC on the embryos indicated that the suppression was mainly caused by the allelochemicals, while the slightest inhibitory effects of RC on the embryos suggested that some intracellular growth-promoting substances were synchronously released when K. mikimotoi cells lyzed. In addition, the most severe growth suppression of embryos by LC indicated that intact cell contact by K. mikimotoi probably also contributed to the inhibitory effects. These results indicated that a dense HAB formed by K. mikimotoi could seriously suppress the development and photosynthesis of S. fusiforme embryos and eventually reduce the seedlings stock.


Assuntos
Dinoflagellida , Sargassum , Contagem de Células , Proliferação Nociva de Algas , Fotossíntese
6.
Harmful Algae ; 65: 19-26, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28526116

RESUMO

The effects of algal blooms on seaweeds have been rarely studied, although harmful algal blooms (HABs) are now normally regarded as worldwide incidents. In the present study, the effects of dense Karenia mikimotoi cells on the growth and photosynthesis of Hizikia fusiformis, a common and commercially cultivated macroalga in coastal waters of the East China Sea (ECS), were studied to understand the possible consequences when the mariculture encountered a dense harmful algal bloom. Furthermore, the counteraction of the latter on the growth and photosynthetic activities of K. mikimotoi was determined to evaluate the contribution of H. fusiformis commercial cultivation to environmental improvements. The results showed that the chlorophyll a (Chl a) contents, maximal photochemical efficiency (Fv/Fm) and relative electron transfer rate (rETR) of gas vesicles (specialized leaves), adult and young receptacles of H. fusiformis were all significantly (P<0.05) inhibited compared with the mono-cultured ones. When compared with mono-cultured H. fusiformis (without K. mikimotoi), the Chl a contents in gas vesicles, adult and young receptacles decreased by 20.6%, 17.6% and 33.2% within 2 weeks. Correspondingly, the Fv/Fm decreased by 7.9%, 37.4% and 43.7%; the apparent photosynthetic efficiency (α) decreased by 9.4%, 47.1% and 48.3%; and rETR decreased by 19.5%, 52.6% and 68.2%, respectively. The Chl a concentration of the mono-cultured K. mikimotoi (without H. fusiformis) increased to 2247.97µgl-1 from 958.11µgl-1 within 14 d. Those of the co-cultivated ones (with H. fusiformis), however, increased to 1591.31µgl-1 on the 8th day and then decreased rapidly to 254.99 (±37.73) µgl-1 after the next 6 days. Furthermore, compared with the mono-cultured K. mikimotoi cells, the Fv/Fm, α and rETRmax of co-cultivated ones decreased by 9.4%, 36.3% and 30.6%, respectively. The results indicated that the mature sporophytes of H. fusiformis were resistant to dense K. mikimotoi blooms and this resistance was organ-dependent as: gas vesicle>adult receptacles>young receptacles. On the other hand, commercial mariculture of H. fusiformis demonstrated the potential of preventing the occurrence of algal blooms.


Assuntos
Alelopatia , Dinoflagellida/fisiologia , Alga Marinha/parasitologia , Clorofila/análise , Proliferação Nociva de Algas , Especificidade de Órgãos , Fotossíntese , Água do Mar/parasitologia , Alga Marinha/crescimento & desenvolvimento , Alga Marinha/imunologia , Alga Marinha/fisiologia
7.
Ecotoxicol Environ Saf ; 111: 271-80, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25450944

RESUMO

Copper (Cu) is an essential micronutrient for algal growth and development; however, it is also generally considered to be one of the most toxic metals when present at higher levels. Seaweeds are often exposed to low concentrations of metals, including Cu, for long time periods. In cases of ocean outfall, they may even be abruptly exposed to high levels of metals. The physiological processes that are active under Cu stress are largely unknown. In this study, the brown macroalga Sargassum fusiforme was cultured in fresh seawater at final Cu concentrations of 0, 4, 8, 24 and 47 µM. The Cu(2+) concentration and chlorophyll autofluorescence were measured to establish the toxic effects of Cu on this economically important seaweed. The accumulation of Cu by S. fusiforme was also dependent upon the external Cu concentration. Algal growth displayed a general decline with increasing media Cu concentrations, indicating that S. fusiforme was able to tolerate Cu stress at low concentrations, while it was negatively impacted at high concentrations. The term "acute stress" was employed to indicate exposure to high Cu concentrations for 1 day in this study. On the other hand, "chronic stress" was defined as exposure to lower sub-lethal Cu concentrations for 7 days. Proteins were extracted from control and Cu-treated S. fusiforme samples and separated by two-dimensional gel electrophoresis. Distinct patterns of protein expression in the acute and chronic stress conditions were observed. Proteins related to energy metabolism and photosynthesis were reduced significantly, whereas those related to carbohydrate metabolism, protein destination, RNA degradation and signaling regulation were induced in S. fusiforme in response to acute copper stress. Energy metabolism-related proteins were significantly induced by chronic Cu stress. Proteins from other functional groups, such as those related to membranes and transport, were present in minor quantities. These results suggest that S. fusiforme is sensitive to excess Cu, regardless of the presence of acute or chronic stress. We discuss the possible function of these identified proteins, taking into consideration the information available from other plant models.


Assuntos
Cobre/toxicidade , Intoxicação por Metais Pesados , Intoxicação/metabolismo , Proteômica , Sargassum/efeitos dos fármacos , Sargassum/metabolismo , Clorofila/metabolismo , Eletroforese em Gel Bidimensional , Metabolismo Energético/efeitos dos fármacos , Monitoramento Ambiental/métodos , Metais Pesados/metabolismo , Fotossíntese/efeitos dos fármacos , Proteoma/análise , Proteoma/efeitos dos fármacos , Proteoma/metabolismo , Água do Mar/análise , Alga Marinha , Poluentes Químicos da Água/toxicidade
8.
PLoS One ; 9(7): e101960, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25025229

RESUMO

Aquatic agriculture in heavy-metal-polluted coastal areas faces major problems due to heavy metal transfer into aquatic organisms, leading to various unexpected changes in nutrition and primary and/or secondary metabolism. In the present study, the dual role of heavy metal copper (Cu) played in the metabolism of photosynthetic organism, the edible seaweed Sargassum fusiforme, was evaluated by characterization of biochemical and metabolic responses using both 1H NMR and GC-MS techniques under acute (47 µM, 1 day) and chronic stress (8 µM, 7 days). Consequently, photosynthesis may be seriously inhibited by acute Cu exposure, resulting in decreasing levels of carbohydrates, e.g., mannitol, the main products of photosynthesis. Ascorbate may play important roles in the antioxidant system, whose content was much more seriously decreased under acute than that under chronic Cu stress. Overall, these results showed differential toxicological responses on metabolite profiles of S. fusiforme subjected to acute and chronic Cu exposures that allowed assessment of impact of Cu on marine organisms.


Assuntos
Cobre/metabolismo , Poluição Ambiental , Sargassum/metabolismo , Aclimatação , Adaptação Fisiológica , Ácido Aspártico/metabolismo , Colina/metabolismo , Ecossistema , Humanos , Malatos/metabolismo , Manitol/metabolismo , Metabolômica/métodos , Metais Pesados , Nitrogênio/metabolismo , Fotossíntese , Estresse Fisiológico
9.
Phytochem Anal ; 24(2): 124-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22782934

RESUMO

INTRODUCTION: Paeoniae radix is one of the most important crude drugs used in Kampo medicines (KMs). A part of its pharmaceutical properties is due to the presence of paeoniflorin (PF) and albiflorin (AF). OBJECTIVE: For the specific and easy identification of PF and AF, an immunostaining technique was developed using anti-PF monoclonal antibody (MAb). METHODOLOGY: PF and AF were treated with a NaIO4 solution and reacted with bovine serum albumin (BSA) preparing PF- and AF-BSA conjugates on the polyethersulphone (PES) membrane. Anti-PF MAb was bound and then antibody labelled with peroxidase directed against anti-PF MAb. Finally, a substrate was added and then PF and AF were detected. RESULTS: Anti-PF MAb recognised not only PF but also AF when 10 µg was present on the PES membrane. As little as 0.5 µg of PF and AF were still detected under immunostaining. Various Paeoniae radix samples and KMs were qualitatively analysed, and total amounts of PF and AF were visually detected by immunostaining technique. This method was applied to investigate the distribution of PF and AF in fresh peony root using immunoblotting by transferred from peony root to the PES membrane. CONCLUSION: The technique permitted the visualisation of PF and AF on PES membrane using immunostaining. The immunostaining technique established would be a powerful tool for probing the sources of PF and AF in plant extracts.


Assuntos
Benzoatos/análise , Hidrocarbonetos Aromáticos com Pontes/análise , Glucosídeos/análise , Immunoblotting/métodos , Animais , Anticorpos Monoclonais/imunologia , Benzoatos/química , Benzoatos/imunologia , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/imunologia , Bovinos , Glucosídeos/química , Glucosídeos/imunologia , Membranas Artificiais , Estrutura Molecular , Monoterpenos , Paeonia/química , Percloratos , Extratos Vegetais/análise , Extratos Vegetais/química , Polímeros/química , Reprodutibilidade dos Testes , Soroalbumina Bovina/química , Compostos de Sódio , Coloração e Rotulagem/métodos , Sulfonas/química
10.
J Asian Nat Prod Res ; 14(6): 555-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22587796

RESUMO

Further investigation on the stems of Artocarpus nitidus subsp. lingnanensis led to the isolation and characterization of a new flavan-3-ol, named artoflavanocoumarin, along with three known compounds (+)-catechin, (+)-afzelechin 3-O-α-L-rhamnoside, and (+)-catechin 3-O-α-L-rhamnoside. Their structures were elucidated on the basis of spectroscopic data.


Assuntos
Artocarpus/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonoides/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Caules de Planta/química , Estereoisomerismo
11.
Molecules ; 17(3): 3324-32, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22418932

RESUMO

Two new phytoecdysteroids, (25S)-20,22-O-(R-ethylidene)inokosterone and 20,22-O-(R-3-methoxycarbonyl)propylidene-20-hydroxyecdysone, together with six known phytoecdysteroids 3-8 were isolated from the roots of Achyranthes bidentata Blume. The new structures were established on the basis of spectroscopic studies and chemical evidences. The absolute configuration at C-25 in the structure of known compound 3 was determined by chemical and spectroscopic means.


Assuntos
Achyranthes/química , Fitosteróis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fitosteróis/química , Extratos Vegetais/química
12.
Fitoterapia ; 82(4): 662-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21316425

RESUMO

The first stilbene possessing a γ-aminobutyric acid lactam function, artocarpene (1), and a new flavanone, 2-hydroxynaringenin 4'-O-ß-d-glucopyranoside (2), were isolated from the stems of Artocarpus nitidus subsp. lingnanensis along with four known compounds, 2-hydroxynaringenin (3), oxyresveratrol (4), 3,4',5-trihydroxy-3'-prenylstilbene (5) and norartocarpetin (6). Their structures were elucidated on the basis of spectroscopic data. Compounds 1 exhibited weak antioxidant activity and 2 displayed weak cytotoxicity against human lung cancer A549 cell line.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Artocarpus/química , Flavanonas/isolamento & purificação , Estilbenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Flavanonas/química , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular , Plantas Medicinais/química , Estilbenos/química
13.
J Asian Nat Prod Res ; 10(11-12): 1155-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19031262

RESUMO

Two new piperidine alkaloids, microcosamines A (1) and B (2), were isolated from the leaves of Microcos paniculata. Their structures were elucidated by spectroscopic analysis. Both new compounds showed significant larvicidal activity against Culex quinquefasciatus.


Assuntos
Alcaloides/química , Piperidinas/química , Tiliaceae/química , Alcaloides/farmacologia , Animais , Culex/efeitos dos fármacos , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Piperidinas/farmacologia , Folhas de Planta
14.
J Nat Prod ; 67(12): 2121-3, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15620268

RESUMO

Three new sesquiterpenes including a rearranged hirsutane, dichomitol (1), an aromadendrane, 2beta,13-dihydroxyledol (2), and a 1,10-seco-2,3-seco-aromadendrane, dichomitone (3), were isolated from mycelial solid cultures of Dichomitus squalens. Their structures were elucidated by spectroscopic methods, and their nematicidal activities against Bursaphelenchus xylophilus were assessed.


Assuntos
Antinematódeos/isolamento & purificação , Nematoides/efeitos dos fármacos , Polyporaceae/química , Sesquiterpenos/isolamento & purificação , Animais , Antinematódeos/química , Antinematódeos/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/farmacologia
15.
J Nat Prod ; 67(4): 734-6, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15104519

RESUMO

Four new sesquiterpene dilactones, mikamicranolide (1), 11 beta,13-dihydromikamicranolide (2), 3 alpha-hydroxy-11 beta,13-dihydrodeoxymikanolide (3), and 2 beta,3 beta-dihydroxy-11 beta,13-dihydrodeoxymikanolide (4), were isolated from the whole plants of Mikania micrantha. Their structures were elucidated on the basis of spectroscopic analysis. Compounds 1 and 2 possess an unusual rearranged 12,8-germacranolide sesquiterpene skeleton.


Assuntos
Lactonas/isolamento & purificação , Mikania/química , Sesquiterpenos/isolamento & purificação , China , Lactonas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Estereoisomerismo
16.
J Antibiot (Tokyo) ; 57(11): 721-5, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15712666

RESUMO

Two new illudane sesquiterpenes, paneolic acid and paneolilludinic acid, along with a known antibiotic diterpene, pleuromutilin, were isolated from the mycelial solid cultures of Panaeolus retirugis. Their structures were elucidated on the basis of spectroscopic analysis. Both compounds exhibited antibacterial activity against Staphylococcus aureus, and paneolic acid showed cytotoxicity to HL60 cell with an IC50 of 18.9 microg/ml.


Assuntos
Antibacterianos/farmacologia , Basidiomycota/metabolismo , Sesquiterpenos/farmacologia , Antibacterianos/isolamento & purificação , Antibióticos Antineoplásicos/biossíntese , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fermentação , Humanos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Rotação Ocular , Sesquiterpenos/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Biotechnol Prog ; 18(4): 862-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12153322

RESUMO

The stress metabolic activities of Panax ginseng (P. ginseng) cells induced by low-energy ultrasound (US) were examined. P. ginseng cells in suspension cultures were exposed to 38.5 kHz US at two power levels (power density 13.7 and 61 mW/cm(3)) for 2 min. The US treatment caused rapid increase in the intracellular levels of polyphenol oxidase (PPO), peroxidase (PO), and phenylalanine ammonia lyase (PAL) and the production of polyphenols (PP) and phenolic compounds. The US-induced enzyme activities and phenolics production are part of plant stress responses to a mechanical stimulus. The much higher PPO activity and rate of PP production in the sonicated cultures are correlated to enzymatic browning, suggestive of physical damage and membrane permeabilization of the cells by US. The cells after sonication also showed decreased water content and cell volume, which may also be attributed to US-induced cell membrane permeabilization and water release. High-pressure shock and fluid shear stress arising from acoustic cavitation were regarded as the major causes of the responses. Nevertheless, the US exposure caused only temporary cell growth depression but no net loss of biomass yield of the culture.


Assuntos
Reação de Maillard , Panax/enzimologia , Panax/metabolismo , Fenóis/metabolismo , Plantas Medicinais/enzimologia , Plantas Medicinais/metabolismo , Ultrassom/efeitos adversos , Biomassa , Células Cultivadas , Ativação Enzimática , Panax/química , Panax/citologia , Doenças das Plantas , Plantas Medicinais/química , Plantas Medicinais/citologia , Água/análise
18.
Biotechnol Bioeng ; 78(1): 81-8, 2002 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-11857284

RESUMO

This work demonstrates the use of low-energy ultrasound (US) to enhance secondary metabolite production in plant cell cultures. Suspension culture of Lithospermum erythrorhizon cells was exposed to low-power US (power density < or = 113.9 mW/cm(3)) for short periods (1-8 min). The US exposure significantly stimulated the shikonin biosynthesis of the cells, and at certain US doses, increased the volumetric shikonin yield by about 60%-70%. Meanwhile, the shikonin excreted from the cells was increased from 20% to 65%-70%, due partially to an increase in the cell membrane permeability by sonication. With combined use of US treatment and in situ product extraction by an organic solvent, or the two-phase culture, the volumetric shikonin yield was increased more than two- to threefold. Increasing in the number of US exposures during the culture process usually resulted in negative effects on shikonin yield but slight stimulation of shikonin excretion. US at relatively high energy levels caused slight cell growth depression (maximum 9% decrease in dry cell weight). Two key enzymes for the secondary metabolite biosynthesis of cells, phenylalanine ammonia lyase and p-hydroxybenzoic acid geranyltransferase, were found to be stimulated by the US. The US stimulation of secondary metabolite biosynthesis was attributed to the metabolic activity of cells activated by US, and more specifically, the defense responses of plant cells to the mechanical stress of US irradiation.


Assuntos
Lithospermum/citologia , Lithospermum/metabolismo , Naftoquinonas/síntese química , Naftoquinonas/metabolismo , Ultrassom , Células Cultivadas/metabolismo , Lithospermum/fisiologia , Naftoquinonas/análise , Permeabilidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
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