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1.
Prep Biochem Biotechnol ; 54(5): 668-679, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38190739

RESUMEN

For complete utilization of high glucose at ∼100 g/L, a high cell density (HCD) continuous fermentation system was established using Lb. delbrueckii NCIM 2025 for the bioproduction of lactic acid (LA). An integrated membrane cell recycling system coupled with the continuous bioreactor, aided to achieve the highest 34.77 g/L h LA productivity and 0.94-0.98 g/g yield. ∼34 times higher productivity was observed (in comparison to batch fermentation conducted in this study), when the continuous operations were carried out at the maximum dilution rate and wet cell weight i.e. 0.36 h-1 and 230 g/L, respectively. These results show the potential of this method for large-scale lactic acid production because it not only produces high titers but also ensures that glucose is used effectively. The method's superior performance in comparison to earlier studies suggests it as an affordable and sustainable alternative for the production of LA.


Asunto(s)
Reactores Biológicos , Fermentación , Glucosa , Ácido Láctico , Lactobacillus delbrueckii , Ácido Láctico/metabolismo , Ácido Láctico/biosíntesis , Glucosa/metabolismo , Lactobacillus delbrueckii/metabolismo , Lactobacillus delbrueckii/crecimiento & desarrollo
2.
Prep Biochem Biotechnol ; 53(9): 1043-1057, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36655700

RESUMEN

Commercial production of lactic acid (LA) utilizes mostly glucose or lactose coupled with yeast extract (YE) as a supplement. With sugars, nitrogen, and vitamin supplementation being most of the LA production costs, the use of inexpensive molasses, a by-product of the sugar industry, can provide considerable cost savings. There are just a few publications on the production of LA from molasses; consequently, the present investigation was conducted using molasses supplemented with yeast extract. The research was done in a continuous-flow, high-cell-density (HCD) bioreactor with an external membrane microfiltration device for cell recycling. The system, run at 1 L with Lactobacillus delbrueckii NCIM 2025, produced a LA yield of 0.95-0.98 g/g from ∼100 g sugars/L when supplemented with 1 g/L YE. Dilution rates in the range of 0.04-0.36 h-1 resulted in volumetric lactic acid productivities in the range of 4.3-27.6 g/L h, which compares favorably with the highest values recorded in literature, for glucose in the presence of YE, which was as high as 30 g/L. The utilization of cane molasses has a significant impact on the economics of lactic acid production, as measured by a comparison of costs with commercial glucose.


Asunto(s)
Bastones , Melaza , Fermentación , Medios de Cultivo , Ácido Láctico/metabolismo , Glucosa
3.
J Assoc Physicians India ; 71(11): 100-102, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38720507

RESUMEN

Acquired amegakaryocytic thrombocytopenia (AATP) is an uncommon cause of severe thrombocytopenia with preserved cells of other lineages, which can present with severe bleeding episodes. We report a case of a 45-year-old male with seronegative arthritis who was diagnosed with idiopathic thrombocytopenic purpura (ITP) and was being treated with steroids for ITP. Despite aggressive treatment, the patient had persistently low levels of platelets. In view of persistent thrombocytopenia, bone marrow biopsy was done and was diagnosed as Acquired Amegakaryocytic Thrombocytopenia (AATP). Patient was successfully treated with cyclosporine. Correct identification of AATP is essential because it can lead to life threatening bleeding manifestations and advance into Aplastic anemia or MDS. How to cite this article: N AM, Rajanna AH, Kamath N. Acquired Amegakaryocytic Thrombocytopenia Misdiagnosed as Immune Thrombocytopenia in a Patient with Seronegative Arthritis: A Case Report. J Assoc Physicians India 2023;71(11):100-102.


Asunto(s)
Artritis , Errores Diagnósticos , Púrpura Trombocitopénica Idiopática , Humanos , Masculino , Persona de Mediana Edad , Púrpura Trombocitopénica Idiopática/diagnóstico , Púrpura Trombocitopénica Idiopática/complicaciones , Artritis/diagnóstico , Artritis/etiología , Púrpura Trombocitopénica/diagnóstico , Ciclosporina/uso terapéutico , Trombocitopenia/diagnóstico , Trombocitopenia/etiología , Inmunosupresores/uso terapéutico , Enfermedades de la Médula Ósea
4.
J Biol Chem ; 296: 100410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33581115

RESUMEN

Trace element selenium (Se) is incorporated as the 21st amino acid, selenocysteine, into selenoproteins through tRNA[Ser]Sec. Selenoproteins act as gatekeepers of redox homeostasis and modulate immune function to effect anti-inflammation and resolution. However, mechanistic underpinnings involving metabolic reprogramming during inflammation and resolution remain poorly understood. Bacterial endotoxin lipopolysaccharide (LPS) activation of murine bone marrow-derived macrophages cultured in the presence or absence of Se (as selenite) was used to examine temporal changes in the proteome and metabolome by multiplexed tandem mass tag-quantitative proteomics, metabolomics, and machine-learning approaches. Kinetic deltagram and clustering analysis indicated that addition of Se led to extensive reprogramming of cellular metabolism upon stimulation with LPS enhancing the pentose phosphate pathway, tricarboxylic acid cycle, and oxidative phosphorylation, to aid in the phenotypic transition toward alternatively activated macrophages, synonymous with resolution of inflammation. Remodeling of metabolic pathways and consequent metabolic adaptation toward proresolving phenotypes began with Se treatment at 0 h and became most prominent around 8 h after LPS stimulation that included succinate dehydrogenase complex, pyruvate kinase, and sedoheptulokinase. Se-dependent modulation of these pathways predisposed bone marrow-derived macrophages to preferentially increase oxidative phosphorylation to efficiently regulate inflammation and its timely resolution. The use of macrophages lacking selenoproteins indicated that all three metabolic nodes were sensitive to selenoproteome expression. Furthermore, inhibition of succinate dehydrogenase complex with dimethylmalonate affected the proresolving effects of Se by increasing the resolution interval in a murine peritonitis model. In summary, our studies provide novel insights into the role of cellular Se via metabolic reprograming to facilitate anti-inflammation and proresolution.


Asunto(s)
Selenio/metabolismo , Selenoproteínas/metabolismo , Animales , Susceptibilidad a Enfermedades/metabolismo , Inflamación/metabolismo , Inflamación/fisiopatología , Lipopolisacáridos/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Peritonitis/tratamiento farmacológico , Peritonitis/inmunología , Proteoma/metabolismo , Proteómica , Selenio/farmacología , Selenoproteínas/genética , Selenoproteínas/fisiología , Succinato Deshidrogenasa/metabolismo
5.
Mol Divers ; 26(5): 2535-2548, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34822095

RESUMEN

Herein, we identified a potent lead compound RRA2, within a series of 54 derivatives of 1,2,4-triazolethiols (exhibit good potency as an anti-mycobacterial agents) against intracellular Mycobacterium tuberculosis (Mtb). Compound RRA2 showed significant mycobactericidal activity against active stage Mycobacterium bovis BCG and Mtb with minimum inhibitory concentration (MIC) values of 2.3 and 2.0 µg/mL, respectively. At MIC value, RRA2 compound yielded 0.82 log reduction of colony-forming unit (cfu) against non-replicating Mtb. Furthermore, RRA2 compound was selected for further target identification due to the presence of alkyne group, showing higher selectivity index (> 66.66 ± 0.22, in non-replicating stage). Using "click" chemistry, we synthesized the biotin linker-RRA2 conjugate, purified with HPLC method and confirmed the conjugation of biotin linker-RRA2 complex by HR-MS analysis. Furthermore, we successfully pulled down and identified a specific target protein GroEl2, from Mtb whole-cell extract. Furthermore, computational molecular modeling indicated RRA2 could interact with GroEl2, which explains the structure-activity relationship observed in this study. GroEL-2 identified a potent and specific target protein for RRA 2 compound in whole cell extract of Mtb H37Ra.


Asunto(s)
Proteínas Bacterianas/análisis , Mycobacterium tuberculosis , Alquinos , Antibacterianos , Antituberculosos/química , Antituberculosos/farmacología , Vacuna BCG , Biotina , Extractos Celulares , Pruebas de Sensibilidad Microbiana , Proteínas , Compuestos de Sulfhidrilo , Triazoles
6.
Reprod Fertil Dev ; 34(3): 331-342, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35086635

RESUMEN

Fertility preservation methods for prepubertal women about to undergo gonadotoxic chemo and/or radiation therapy are limited. Therefore, the aim of this study was to investigate the feasibility to develop an alternative fertility preservation method based on an ex vivo perfusion platform for whole ewe ovaries. Thirteen ewe ovaries were divided into two groups (group 1 and 2) that were perfused in a bioreactor for up to 7days. Group 1 (n =3) were stimulated with human menopausal gonadotropin (hMG) administered in single daily dose, while group 2 (n =10) were stimulated continuously for 24h. The perfused ovaries in group 1 showed no significant differences in follicular density, sub-follicular morphology and oocyte quality after ischaemia and after ex vivo perfusion compared with non-perfused control ovaries. The perfused ovaries in group 2 showed a significant decrease in the follicular reserve and oocyte quality compared with the control group. In total, 16 GV-MI oocytes were retrieved from both groups. This study describes for the first time the ex vivo maintenance of viable follicles of ewe ovaries with oocyte integrity and the retrieval of oocytes after ex vivo hormonal perfusion with two different protocols for up to 7days.


Asunto(s)
Preservación de la Fertilidad , Animales , Femenino , Preservación de la Fertilidad/métodos , Recuperación del Oocito , Oocitos , Ovario , Perfusión , Ovinos
7.
Prep Biochem Biotechnol ; 52(8): 924-936, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34895061

RESUMEN

Renewable natural gas (RNG) produced from anaerobic digestion (AD) of agricultural residues is emerging a serious biofuel alternative. Complex nature of lignocellulosic biomass residues coupled with complex biochemical transformations involving a large spectrum of microbial communities make anaerobic digestion of biomass difficult to understand and control. The present work aims at studying adaptation of microbial consortia in AD to substrates changes and correlating these to biogas generation. The double edged study deals with (a) using a common starting culture inoculum on different fractions of pretreated lignocellulosic biomass (LBM) fractions; and (b) using different starter inocula for gas generation from simple glucose substrate. Taxonomic analysis using 16S amplicon sequencing is shown to highlight changes in microbial community structure and predominance, majorly in hydrolytic bacterial populations. Observed variations in the rate of digestion with different starter inocula could be related to differences in microbial community structure and relative abundance. Results with different treated biomass fractions as substrates indicated that AD performance could be related to abundance of substrate-specific microbial communities. The work is a step to a deeper understanding of AD processes that may lead to better control and operation of AD for super-scale production of RNG from biomass feedstocks.


Asunto(s)
Biocombustibles , Consorcios Microbianos , Anaerobiosis , Biomasa , Hidrólisis
8.
Am J Transplant ; 21(6): 2220-2230, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33249756

RESUMEN

The organ damage incurred during the cold storage (CS) of intestinal grafts has short and long-term consequences. Animal studies suggest that additional luminal preservation (LP) with polyethylene glycol (PEG) may alleviate this damage. This study aims to validate these findings using human intestines. Ileal segments, perfused intravascularly with IGL-1 solution, were procured from 32 multiorgan donors and divided into two parts: one containing a PEG 3350-based solution introduced luminally (LP group) and another one without luminal treatment (control). Sampling was performed after 4 h, 8 h, 14 h, and 24 h of CS. Histology was assessed using the Chiu/Park score. Tight junctions (TJ), several inflammatory markers, and transcription factors were examined by immunofluorescence, ddPCR, and western blot. Tissue water content (edema) was also measured. Apoptotic activity was assessed with caspase -2, -3, and -9 assays. LP significantly lowered mucosal injury at all time points. Redistribution of TJ proteins occurred earlier and more severely in the control group. After 24 h of CS, LP intestines showed an emerging unfolding protein response. Increased caspase-3 and -9 activity was found in the control group. The current results indicate that luminal PEG is safe and effective in reducing damage to the intestinal epithelium during CS.


Asunto(s)
Soluciones Preservantes de Órganos , Daño por Reperfusión , Animales , Humanos , Mucosa Intestinal , Intestinos , Preservación de Órganos , Polietilenglicoles , Uniones Estrechas
9.
Prep Biochem Biotechnol ; 51(10): 1046-1055, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33719922

RESUMEN

2,3-Butanediol (2,3-BDO) has varied applications in chemical, pharmaceutical, & food industry. Microorganisms belonging to Klebsiella, Enterobacter & Serratia genera are well-known producers of 2,3-BDO. However, they have limited usage in industrial-scale owing to their pathogenic nature. A nonpathogenic soil isolate identified as Bacillus licheniformis (BL1) was thus investigated for 2,3-BDO production. Soy flakes, soy flour, defatted soy, and soybean meal-based hydrolysates replaced yeast extract and peptone as nitrogen sources. Defatted soy flakes and soybean meal hydrolysate led to an equivalent 2,3-BDO yield and productivity as compared to that of Yeast Extract and peptone. The pH and oxygen variation influenced the proportion of various products of the mixed acid-butanediol pathway. Further, the batch mode fermentation with soy hydrolysate and optimized process parameter resulted in 2,3-BDO titer, yield and productivity of 11.06 g/L, 0.43 g/g and 0.48 g/L h respectively. Glucose concentration above 5% was inhibitory and led to reduction in the specific growth rate of BL1 in batch cultivation. Intermittent glucose feeding in fed-batch mode overcame this substrate limitation resulting in increased titers (49.8 g/L) and productivity (0.62 g/L h). Modified medium containing soy hydrolysate as nitrogen source with fermentation process optimization resulted in 67% decrease in medium cost for 2,3-BDO production.


Asunto(s)
Bacillus licheniformis/metabolismo , Butileno Glicoles/metabolismo , Medios de Cultivo/metabolismo , Fermentación , Glucosa/metabolismo , Microbiología Industrial/métodos , Nitrógeno/metabolismo , Glycine max/metabolismo
10.
Funct Integr Genomics ; 20(5): 711-721, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32705366

RESUMEN

Puccinia triticina (P. triticina) is one of the most devastating fungal pathogens of wheat which causes significant annual yield loss to the crop. Understanding the gene regulatory mechanism of the biotrophic pathogen is one of the important aspects of host-pathogen interaction studies. Dicer-like genes are considered as important mediators of RNAi-based gene regulation. In this study, we report the presence of three Dicer-like genes (Pt-DCL1, Pt-DCL2, Pt-DCL3) in P. triticina genome identified through computational and biological analyses. Quantitative real-time PCR studies revealed an increase in the expression of these genes in germinating spore stages. Heterologous expression combined with mass spectrometry analysis of Pt-DCL2 confirmed the presence of a canonical Dicer-like gene in P. triticina. Phylogenetic analysis of the Pt-DCLs with the Dicer-like proteins from other organisms showed a distinct cluster of rust pathogens from the order Pucciniales. The results indicated a species-specific duplication of Dicer-like genes within the wheat rust pathogens. This study, for the first time, reports the presence of Dicer-dependent RNAi pathway in P. triticina that may play a role in gene regulatory mechanism of the pathogen during its development. Our study serves as a vital source of information for further RNAi-based molecular studies for better understanding and management of the wheat leaf rust disease.


Asunto(s)
Genes Fúngicos , Puccinia/genética , Ribonucleasa III/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Filogenia , Puccinia/metabolismo , Ribonucleasa III/clasificación , Ribonucleasa III/metabolismo , Triticum/microbiología
11.
NMR Biomed ; 33(2): e4192, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31733128

RESUMEN

Acute respiratory distress syndrome (ARDS), manifested by intricate etiology and pathophysiology, demands careful clinical surveillance due to its high mortality and imminent life support measures. NMR based metabolomics provides an approach for ARDS which culminates from a wide spectrum of illness thereby confounding early manifestation and prognosis predictors. 1 H NMR with its manifold applications in critical disease settings can unravel the biomarker of ARDS thus holding potent implications by providing surrogate endpoints of clinical utility. NMR metabolomics which is the current apogee platform of omics trilogy is contributing towards the possible panacea of ARDS by subsequent validation of biomarker credential on larger datasets. In the present review, the physiological derangements that jeopardize the whole metabolic functioning in ARDS are exploited and the biomarkers involved in progression are addressed and substantiated. The following sections of the review also outline the clinical spectrum of ARDS from the standpoint of NMR based metabolomics which is an emerging element of systems biology. ARDS is the main premise of intensivists textbook, which has been thoroughly reviewed along with its incidence, progressive stages of severity, new proposed diagnostic definition, and the preventive measures and the current pitfalls of clinical management. The advent of new therapies, the need for biomarkers, the methodology and the contemporary promising approaches needed to improve survival and address heterogeneity have also been evaluated. The review has been stepwise illustrated with potent biometrics employed to selectively pool out differential metabolites as diagnostic markers and outcome predictors. The following sections have been drafted with an objective to better understand ARDS mechanisms with predictive and precise biomarkers detected so far on the basis of underlying physiological parameters having close proximity to diseased phenotype. The aim of this review is to stimulate interest in conducting more studies to help resolve the complex heterogeneity of ARDS with biomarkers of clinical utility and relevance.


Asunto(s)
Biomarcadores/metabolismo , Espectroscopía de Resonancia Magnética , Síndrome de Dificultad Respiratoria/diagnóstico por imagen , Síndrome de Dificultad Respiratoria/metabolismo , Animales , Cuidados Críticos , Humanos , Metabolómica , Análisis Multivariante , Síndrome de Dificultad Respiratoria/epidemiología , Síndrome de Dificultad Respiratoria/fisiopatología
12.
Bioorg Chem ; 95: 103543, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31911303

RESUMEN

Present work describes the purification of an acidic ß-galactosidase from Lens culinaris (Lsbgal) to homogeneity via 857 fold with specific activity of 87 U/mg. The molecular mass of purified Lsbgal was estimated ~ 76 kDa by Size Exclusion Chromatography on Superdex-200 (ÄKTA purifier) and on SDS-PAGE, showed hetero-dimeric subunits i.e. 45 kDa and 30 kDa. The purified Lsbgal showed glycoproteinous nature when applied to Con-A Sepharose chromatography. Biochemical studies revealed that optimum condition for purified Lsbgal against o, nitophenyl ß-d-galactopyranoside (ONPG) as a substrate was pH 3.0, 58 °C with an activation energy (Ea) 8.1 kcal/mole and Q10 1.8. Lsbgal hydrolyses ONPG with Km value 1.21 mM and Vmax 90.90 µmoles/min/mg. Purified Lsbgal when incubated with high lactose concentration showed transgalactosylation activity which lead to the formation of trisaccharides as a major product of total GOS. Therefore, the purified Lsbgal could be used as potential alternative in food industry and would be further explicated for trisaccharides synthesis.


Asunto(s)
Lens (Planta)/enzimología , Oligosacáridos/síntesis química , beta-Galactosidasa/aislamiento & purificación , Cromatografía en Gel/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico/métodos , Cromatografía en Capa Delgada/métodos , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Cinética , Temperatura , beta-Galactosidasa/metabolismo
13.
Funct Integr Genomics ; 19(3): 391-407, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30618015

RESUMEN

Cross-kingdom RNAi is a well-documented phenomenon where sRNAs generated by host and pathogens may govern resistance or susceptible phenotypes during host-pathogen interaction. With the first example of the direct involvement of fungal generated sRNAs in virulence of plant pathogenic fungi Botrytis cinerea and recently from Puccinia striiformis f. sp. tritici, we attempted to identify sRNAs in Puccinia triticina (P. triticina). Four sRNA libraries were prepared and sequenced using Illumina sequencing technology and a total of ~ 1-1.28 million potential sRNAs and two microRNA-like small RNA (mil-RNAs) candidates were identified. Computational prediction of targets using a common set of sRNAs and P. triticina mil-RNAs (pt-mil-RNAs) within P. triticina and wheat revealed the majority of the targets as repetitive elements in P. triticina whereas in wheat, the target genes were identified to be involved in many biological processes including defense-related pathways. We found 9 receptor-like kinases (RLKs) and 14 target genes of each related to reactive oxygen species (ROS) pathway and transcription factors respectively, including significant numbers of target genes from various other categories. Expression analysis of twenty selected sRNAs, targeting host genes pertaining to ROS related, disease resistance, metabolic processes, transporter, apoptotic inhibitor, and transcription factors along with two pt-mil-RNAs by qRT-PCR showed distinct patterns of expression of the sRNAs in urediniospore-specific libraries. In this study, for the first time, we report identification of novel sRNAs identified in P. triticina including two pt-mil-RNAs that may play an important role in biotrophic growth and pathogenicity.


Asunto(s)
Basidiomycota/genética , Interacciones Huésped-Patógeno/genética , MicroARNs/genética , Basidiomycota/patogenicidad , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Triticum/genética , Triticum/microbiología
14.
Photosynth Res ; 139(1-3): 539-551, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29987549

RESUMEN

Ulva lactuca is regarded as a prospective energy crop for biorefinery owing to its affluent biochemical composition and high growth rate. In fast-growing macroalgae, biomass development strictly depends on external nitrogen pools. Additionally, nitrogen uptake rates and photosynthetic pigment content vary with type of nitrogen source and light conditions. However, the combined influence of nitrogen source and light intensity on photosynthesis is not widely studied. In present study, pale green phenotype of U. lactuca was obtained under high light (HL) condition when inorganic nitrogen (nitrate) in the media was substituted with organic nitrogen (urea). Further, pale green phenotype survived the saturating light intensities in contrast to the normal pigmented control which bleached in HL. Detailed analysis of biochemical composition and photosynthesis was performed to understand functional antenna size and photoprotection in pale green phenotype. Under HL, urea-grown cultures exhibited increased growth rate, carbohydrate and lipid content while substantial reduction in protein, chlorophyll content and PSII antenna size was observed. Further, in vivo slow and polyphasic chlorophyll a (Chl a) fluorescence studies revealed reduction in excitation pressure on PSII along with low non-photochemical quenching thus, transmitting most of the absorbed energy into photochemistry. The results obtained could be correlated to previous report on cultivation of U. lactuca through saturating summer intensities (1000 µmole photons m-2 s-1) in urea based: poultry litter extract (PLE). Having proved critical role of urea in conforming photoprotection, the application PLE was authenticated for futuristic, sustainable and year-round biomass cultivation.


Asunto(s)
Fotoquímica/métodos , Algas Marinas/metabolismo , Clorofila/metabolismo , Fotosíntesis/fisiología
15.
Photosynth Res ; 139(1-3): 553-567, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29860703

RESUMEN

This study is the first to explore the influence of incident light intensity on the photosynthetic responses under mixotrophic growth of microalga Asteracys sp. When grown mixotrophically, there was an enhanced regulation of non-photochemical quenching (NPQ) of the excited state of chlorophyll (Chl) a within the cells in response to white cool fluorescent high light (HL; 600 µmol photons m-2 s-1). Simultaneous measurement of reactive oxygen species (ROS) production as malondialdehyde (MDA) and ascorbate peroxidase (APX), an ROS scavenger, showed improved management of stress within mixotrophic cells under HL. Despite the observed decrease in quantum yield of photosynthesis measured through the Chl a fluorescence transient, no reduction in biomass accumulation was observed under HL for mixotrophy. However, biomass loss owing to photoinhibition was observed in cells grown phototrophically under the same irradiance. The measurements of dark recovery of NPQ suggested that "state transitions" may be partly responsible for regulating overall photosynthesis in Asteracys sp. The partitioning of photochemical and non-photochemical processes to sustain HL stress was analysed. Collectively, this study proposes that mixotrophy using glucose leads to a change in the photosynthetic abilities of Asteracys sp. while enhancing the adaptability of the alga to high irradiances.


Asunto(s)
Luz , Microalgas/metabolismo , Ascorbato Peroxidasas/metabolismo , Clorofila/metabolismo , Malondialdehído/metabolismo , Microalgas/efectos de la radiación , Fotosíntesis/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo
16.
J Fluoresc ; 29(5): 1213-1219, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31529260

RESUMEN

Nitrogen doped carbon quantum dots (NCQDs) were synthesized via hydrothermal route. The NCQDs are thermally and optically stable with high flouresence yield. For the synthesis of NCQDs, citric acid and urea was taken as carbon and nitrogen sources, respectively. The Transmission Electron Microscopy (TEM) of these quantum dots revealed nearly spherical shape and average size of 1.5 nm, which was calculated using Image J software. The quantum dots were also well-characterized using spectroscopic techniques such as FTIR, UV-Visible absorption and fluorescence. These synthesized and characterized dots were utilized for selective detection of lactose in Milli Q water. The bioprobe provide a wide linear range varying from (10.00-77.41) µM with limit of detection 11.36 µM and sensitivity equal to (0.0065 ± 0.0002) µM-1. Graphical Abstract.


Asunto(s)
Colorantes Fluorescentes/química , Lactosa/análisis , Lens (Planta)/enzimología , Nitrógeno/química , Puntos Cuánticos/química , beta-Galactosidasa/metabolismo , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/metabolismo , Nitrógeno/metabolismo , Puntos Cuánticos/metabolismo , Espectrometría de Fluorescencia
17.
Acta Obstet Gynecol Scand ; 98(9): 1127-1138, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30932168

RESUMEN

INTRODUCTION: Uterus transplantation has recently proved that infertility in women with uterine factor infertility can be cured. It is still an experimental procedure with numerous critical details remaining to be established, including tolerance to warm and cold ischemic insults. In preparation for human uterus transplantation trials, most teams use the sheep as a model system for research and team training, since the vasculature and the uterus is of similar size as in the human. We, therefore, aimed to develop an ex vivo sheep uterus reperfusion platform that mimics the reperfusion situation so that initial assessments and comparisons can be performed without the need for costly and labor-intensive in vivo transplantation experiments. MATERIAL AND METHODS: Isolated sheep uteri were perfused with the preservation solution IGL-1 and were then exposed to cold ischemia for either 4 (n = 6) or 48 hours (n = 7). Uteri were then reperfused for 48 hours under normothermic conditions with an oxygenated recirculating perfusate containing growth factors and synthetic oxygen carriers. Histological and biochemical analysis of the perfusate was conducted to assess reperfusion injury. RESULTS: Quantification of cell density indicated no significant edema in the myometrium or in the endometrium of uteri exposed to 4 hours cold ischemia and then a normothermic ex vivo reperfusion for 48 hours. Only the outer serosa layer and the inner columnar luminal epithelial cells were affected by the reperfusion. However, a much faster and severe reperfusion damage of all uterine layers were evident during the reperfusion experiment following 48 hours of cold ischemia. This was indicated by major accumulation of extracellular fluid, presence of apoptotic-labeled glandular epithelial layer and vascular endothelium. A significant accumulation of lactate was measured in the perfusate with a subsequent decrease in pH. CONCLUSIONS: We developed a novel ex vivo sheep uterus model for prolonged perfusion. This model proved to be able to distinguish reperfusion injury-related differences associated to organ preservation. The experimental setup is a platform that can be used to conduct further studies on uterine ischemia- and reperfusion injury that may lead to improved human uterus transplantation protocols.


Asunto(s)
Modelos Animales de Enfermedad , Preservación de Órganos/métodos , Reperfusión/métodos , Útero/trasplante , Animales , Isquemia Fría , Femenino , Soluciones Preservantes de Órganos , Daño por Reperfusión/prevención & control , Ovinos
18.
Biotechnol Lett ; 41(6-7): 823-836, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31093837

RESUMEN

OBJECTIVE: Metabolic engineering efforts are guided by identifying gene targets for overexpression and/or deletion. Isobutanol, a biofuel candidate, is biosynthesized using the valine biosynthesis pathway and enzymes of the Ehrlich pathway. Most reported studies for isobutanol production in Escherichia coli employ multicopy plasmids, an approach that suffers from disadvantages such as plasmid instability, increased metabolic burden, and use of antibiotics to maintain selection pressure. Cofactor imbalance is another issue that may limit production of isobutanol, as two enzymes of the pathway utilize NADPH as a cofactor. RESULTS: To address these issues, we constructed E. coli strains with chromosomally-integrated, codon-optimized isobutanol pathway genes (ilvGM, ilvC, kivd, adh) selected on the basis of their cofactor preferences. Genes involved in diverting pyruvate flux toward fermentation byproducts were deleted. Metabolite analyses of the constructed strains revealed extracellular accumulation of significant amounts of isobutyraldehyde, a pathway intermediate, and the overflow metabolites 2,3-butanediol and acetol. CONCLUSIONS: These results demonstrate that the genetic modifications carried out led to activation of alternative pathways that diverted carbon flux toward formation of unwanted metabolites. The present study highlights how precursor metabolites can be metabolized through enzymatic routes that have not been considered important in previous studies due to the different strategies employed therein. The insights gained from the present study will allow rational genetic modification of host cells for production of metabolites of interest.


Asunto(s)
Butanoles/metabolismo , Ciclo del Carbono , Escherichia coli/genética , Escherichia coli/metabolismo , Ingeniería Metabólica/métodos , Redes y Vías Metabólicas/genética
19.
Prep Biochem Biotechnol ; 49(5): 444-452, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30861359

RESUMEN

Enzymatic interesterification was carried out between high-oleic canola oil and fully hydrogenated soybean oil using indigenously immobilized Thermomyces lanuginosus lipas substrate concentration, moisture content of enzyme, and enzyme load. Interesterification resulted in a decrease in the concentration of tri-unsaturated and trisaturated TAG and an increase of mono- and di-saturated TAG as observed by reversed-phase HPLC. The alteration in TAG composition and the presence of new TAG species after interesterification was correlated with extended plasticity characterized by lower slip melting point with a significant change in functionality and consistency of the interesterified product. Thermal and structural properties of the blends before and after interesterification were assessed by differential scanning calorimetry (DSC), X-ray diffraction and polarized light microscopy. Trans-fat analysis indicated the absence of any trans fatty acid in the final interesterified product. The resultant interesterified products with varying slip melting points can be used in the formulation of healthier fat and oil products and address a critical industrial demand for trans free formulations for base-stocks of spreads, margarines, and confectionary fats.


Asunto(s)
Enzimas Inmovilizadas/química , Lipasa/química , Triglicéridos/química , Brassica rapa/química , Esterificación , Eurotiales/enzimología , Tecnología Química Verde/métodos , Aceite de Brassica napus/química , Aceite de Soja/química , Glycine max/química , Estereoisomerismo , Ácidos Grasos trans/análisis , Triglicéridos/análisis , Agua/química
20.
Prep Biochem Biotechnol ; 48(1): 6-12, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-28976230

RESUMEN

Propionic acid production from glucose was studied using Propionibacterium freudenreichii shermanii. Conditions were optimized for high yields of propionic acid and total organic acids by sequential optimization of parameters like pH, inoculum age, inoculum volume and substrate concentration. Near-theoretical yield (0.54 ± 0.023 g/g) was achieved for propionic acid with fermentation of 1% glucose using 20% (v/v) of 48 hr old P. shermanii at 30°C, pH maintained at 5.5. Total organic acid yield under these conditions was 0.74 ± 0.06 g/g. The study resulted in achieving 98% and 95% theoretical yields of propionic acid and total organic acids, respectively. Under optimized conditions, along with organic acids, P. shermanii also produced vitamin B12 and trehalose intracellularly, showing its potential to be used as a cell factory.


Asunto(s)
Glucosa/metabolismo , Microbiología Industrial/métodos , Propionatos/metabolismo , Propionibacterium freudenreichii/crecimiento & desarrollo , Técnicas de Cultivo Celular por Lotes/métodos , Fermentación , Propionibacterium freudenreichii/metabolismo , Trehalosa/metabolismo , Vitamina B 12/metabolismo
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