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1.
Prep Biochem Biotechnol ; 47(3): 245-253, 2017 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-27715472

RESUMEN

Galactooligosaccharides (GOS) are nondigestible dietary fibers which have a beneficial effect on human health by promoting the growth of probiotic bacteria in the gut. In addition, other health benefits have been reported from oligosaccharides consumption such as stimulation of intestinal mobility, colon cancer prevention, mineral absorption as well as protection against certain pathogenic bacterial infections. The goal of this research was to develop an efficient biotransformation system using a consortium of microbes for the production of ≥85% pure GOS and reusing the cell biomass in repeated cycles of biotransformation. Production of GOS by lactose transgalactosylation using whole cells of Sporobolomyces singularis MTCC 5491 as a source of ß-galactosidase and monosaccharides utilization by yeast isolate (NUTIDY007) were studied. For increasing the purity of GOS, growth and bioconversion parameters on the transgalactosylation by the whole cells were investigated. Further, continuous production of GOS was studied in a reactor with microfiltration membrane system. A maximum GOS purity of 42% was achieved using single culture of S. singularis. Under optimized conditions, single culture of S. singularis produced a maximum of 56% pure GOS. Addition of second culture to the reaction mixture for utilization of glucose significantly increased the GOS purity from 56% to ≥85%. The product consisted of tri- to penta-galactooligosaccharides. Trisaccharides were the main component of the reaction mixture. A maximum productivity of 10.9 g/L/hr was obtained under the optimum conditions.


Asunto(s)
Basidiomycota/enzimología , Galactosa/metabolismo , Oligosacáridos/metabolismo , Basidiomycota/crecimiento & desarrollo , Basidiomycota/metabolismo , Reactores Biológicos , Biotransformación , Fermentación , Microbiología Industrial , Lactosa/metabolismo , Temperatura , beta-Galactosidasa/metabolismo
2.
Protein Expr Purif ; 107: 1-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25462807

RESUMEN

Ability of microorganisms to grow at alkaline pH makes them an attractive target for several industrial applications. Thus, search for new extremozyme producing microorganisms must be a continuous exercise. Hence, we isolated a potent alkaline protease producing bacteria from slaughter house soil. The morphological, biochemical and 16S rDNA gene sequencing studies revealed that the isolated bacteria is Stenotrophomonas maltophilia strain SK. Alkaline protease from S. maltophilia strain SK was purified by using ammonium sulphate precipitation and DEAE-cellulose ion exchange column chromatography. The purified enzyme was optimally active at pH 9.0 and temperature 40°C with broad substrate specificity. It was observed that the metal ions such as Ca(++), Mg(++) and Fe(+++) completely repressed the enzyme activity. The enzyme was stable in presence of various water miscible solvents like ethanol, methanol, isopropanol at 25% (v/v) concentration and less stable at 37.5% (v/v) concentration. These robust properties of enzyme might be applicable for various applications in detergent and pharmaceutical industries.


Asunto(s)
Proteínas Bacterianas/química , Endopeptidasas/química , Endopeptidasas/aislamiento & purificación , Stenotrophomonas maltophilia/enzimología , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Endopeptidasas/genética , Endopeptidasas/metabolismo , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Metales/metabolismo , Datos de Secuencia Molecular , Filogenia , Microbiología del Suelo , Stenotrophomonas maltophilia/química , Stenotrophomonas maltophilia/genética , Stenotrophomonas maltophilia/aislamiento & purificación , Especificidad por Sustrato , Temperatura
3.
Artículo en Inglés | MEDLINE | ID: mdl-38985387

RESUMEN

Therapies targeting gut microbiota are being extensively researched for colitis patients. In this study, we have tested the efficacy of indigenously isolated strains Lactiplantibacillus plantarum Lp1-IC and Limosilactobacillus fermentum FS-10 and their combination with short-chain fructooligosaccharides (sc-FOS) in mice models of DSS-induced colitis. For a desired efficacy, a synbiotic should be very meticulously formulated with the right choice of prebiotic and probiotic. Therefore, the ability of lactobacilli to utilize scFOS for growth was first tested by culturing the strains in a specially designed minimal media supplemented with scFOS as carbon source. The bacteria utilized scFOS and produced metabolites such as acetate and lactate. Thereafter, the in vitro anti-inflammatory effect was tested on markers such as TNF-alpha (TNF-α), nitric oxide and IL-10 in human monocyte (THP-1) and mouse macrophage (Raw 264.7) cell lines. The in vivo efficacy was studied in mice model of DSS-induced colitis, and the effect on the systemic and localized inflammatory markers was assessed in serum and colon tissue samples respectively. Administration of DSS elicited predominant clinical signs of weight loss, diarrhoea, faecal occult blood, increase in inflammatory markers and extensive damage of colon tissue. These symptoms were significantly reversed in all the treatment groups; however, the combination of lactobacilli and scFOS performed better than the individual ingredients. The study highlights the potential of the indigenous lactobacilli strains, scFOS and their combination for management of gut inflammation in colitis patients.

4.
J Orthop Case Rep ; 13(2): 51-54, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37144064

RESUMEN

Introduction: Aneurysmal bone cysts (ABCs) are a group of benign, expansile, locally aggressive lesion characterized by fluid-filled cysts usually in the metaphyseal end of long bones. They usually affect children and young adults, with an atypical etiology and uncommon presentation. Treatment modalities include en bloc resection and curettage with or without bone graft or bone substitute augmentation with instrumentation, sclerosing agents, arterial embolization, and adjuvant radiotherapy. Case Report: We report a rare case of ABC with pathological fracture in the proximal femur of a 13-year-old male patient, who presented to the emergency department with severe pain in the right hip and inability to walk following trivial fall while playing. Curettage with open biopsy was performed followed by implantation with modified hydroxyapatite granules and internal fixation for the subtrochanteric fracture with pediatric dynamic hip screw and four hole plate, with a favorable outcome. Conclusion: There is a lack of a standard guideline for the management on account of uniqueness of these cases; curettage with bone graft or bone substitutes in conjunction with internal fixation of associated pathologic fracture yields bony union with adequate clinical results.

5.
Environ Technol ; : 1-24, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37491760

RESUMEN

Bioelectrochemical systems (BES) have emerged as a sustainable and highly promising technology that has garnered significant attention from researchers worldwide. These systems provide an efficient platform for the removal and recovery of valuable products from wastewater, with minimal or no net energy loss. Among the various types of BES, microbial fuel cells (MFCs) are a notable example, utilizing microbial biocatalytic activities to generate electrical energy through the degradation of organic matter. Other BES variants include microbial desalination cells (MDCs), microbial electrolysis cells (MECs), microbial electrosynthesis cells (MXCs), microbial solar cells (MSCs), and more. BESs have demonstrated remarkable potential in the recovery of diverse products such as hydrogen, methane, volatile fatty acids, precious nutrients, and metals. Recent advancements in scaling up BESs have facilitated a more realistic assessment of their net energy recovery and resource yield in real-world applications. This comprehensive review focuses on the practical applications of BESs, from laboratory-scale developments to their potential for industrial commercialization. Specifically, it highlights successful examples of value-added product recovery achieved through various BES configurations. Additionally, this review critically evaluates the limitations of BESs and provides suggestions to enhance their performance at a larger scale, enabling effective implementation in real-world scenarios. By providing a thorough analysis of the current state of BES technology, this review aims to emphasize the tremendous potential of these systems for sustainable wastewater treatment and resource recovery. It underscores the significance of bridging the gap between laboratory-scale achievements and industrial implementation, paving the way for a more sustainable and resource-efficient future.

6.
BioTech (Basel) ; 11(3)2022 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-35997344

RESUMEN

Due to the continuous depletion of natural resources currently used for electricity generation, it is imperative to develop alternative energy sources. Human waste is nowadays being explored as an efficient source to produce bio-energy. Human waste is renewable and can be used as a source for an uninterrupted energy supply in bioelectricity or biofuel. Annually, human waste such as urine is produced in trillions of liters globally. Hence, utilizing the waste to produce bioenergy is bio-economically suitable and ecologically balanced. Microbial fuel cells (MFCs) play a crucial role in providing an effective mode of bioelectricity production by implementing the role of transducers. MFCs convert organic matter into energy using bio-electro-oxidation of material to produce electricity. Over the years, MFCs have been explored prominently in various fields to find a backup for providing bioenergy and biofuel. MFCs involve the role of exoelectrogens which work as transducers to convert the material into electricity by catalyzing redox reactions. This review paper demonstrates how human waste is useful for producing electricity and how this innovation would be beneficial in the long term, considering the current scenario of increasing demand for the supply of products and shortages of natural resources used to produce biofuel and bioelectricity.

7.
ChemSusChem ; 10(11): 2527-2533, 2017 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-28406578

RESUMEN

Growing concern with the effects of CO2 emissions due to the combustion of petroleum-based transportation fuels has motivated the search for means to increase engine efficiency. The discovery of ethers with low viscosity presents an important opportunity to improve engine efficiency and fuel economy. We show here a strategy for the catalytic synthesis of such ethers by reductive etherification/O-alkylation of alcohols using building blocks that can be sourced from biomass. We find that long-chain branched ethers have several properties that make them superior lubricants to the mineral oil and synthetic base oils used today. These ethers provide a class of potentially renewable alternatives to conventional lubricants produced from petroleum and may contribute to the reduction of greenhouse gases associated with vehicle emissions.


Asunto(s)
Biomasa , Éter/síntesis química , Lubricantes/síntesis química , Emisiones de Vehículos , Alcoholes , Automóviles , Estructura Molecular
8.
AMB Express ; 6(1): 114, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27844458

RESUMEN

Fungal chitinase have tremendous applications in biotech industries, with this approach we focused on extracellular chitinase from Rhizopus stolonifer NCIM 880 for the formation of fungal protoplasts. The maximum chitinase production reached after 24 h at 2.5% colloidal chitin concentration in presence of starch as an inducer. Chitinase was extracted efficiently at 65% cold acetone concentration and then purified by using DEAE-Cellulose column chromatography. Purified chitinase having molecular weight 22 kDa with single polypeptide chain was optimally active at pH 5.0 and temperature 30 °C. The purified chitinase revealed kinetic properties like Km 1.66 mg/ml and Vmax 769 mM/min. Crude chitinase extract efficiently formed protoplasts from A. niger, A. oryzae, T. viride and F. moniliforme. The formed protoplasts of A. niger and T. viride showed 70 and 66% regeneration frequency respectively. Further, intergeneric fusants were developed successfully and identified at molecular level using RNA profiling. Thus, this study could be useful for strain improvement of various fungi for biotechnological applications.

9.
Org Lett ; 14(3): 672-5, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22260623

RESUMEN

The photoredox-catalyzed coupling of N-aryltetrahydroisoquinoline and Michael acceptors was achieved using Ru(bpy)(3)Cl(2) or [Ir(ppy)(2)(dtb-bpy)]PF(6) in combination with irradiation at 455 nm generated by a blue LED, demonstrating the trapping of visible light generated α-amino radicals. While intermolecular reactions lead to products formed by a conjugate addition, in intramolecular variants further dehydrogenation occurs, leading directly to 5,6-dihydroindolo[2,1-a]tetrahydroisoquinolines, which are relevant as potential immunosuppressive agents.

10.
PLoS One ; 7(5): e37649, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22629438

RESUMEN

Angiotensin-converting enzyme 2 (ACE2) is expressed in the kidney and may be a renoprotective enzyme, since it converts angiotensin (Ang) II to Ang-(1-7). ACE2 has been detected in urine from patients with chronic kidney disease. We measured urinary ACE2 activity and protein levels in renal transplant patients (age 54 yrs, 65% male, 38% diabetes, n = 100) and healthy controls (age 45 yrs, 26% male, n = 50), and determined factors associated with elevated urinary ACE2 in the patients. Urine from transplant subjects was also assayed for ACE mRNA and protein. No subjects were taking inhibitors of the renin-angiotensin system. Urinary ACE2 levels were significantly higher in transplant patients compared to controls (p = 0.003 for ACE2 activity, and p≤0.001 for ACE2 protein by ELISA or western analysis). Transplant patients with diabetes mellitus had significantly increased urinary ACE2 activity and protein levels compared to non-diabetics (p<0.001), while ACE2 mRNA levels did not differ. Urinary ACE activity and protein were significantly increased in diabetic transplant subjects, while ACE mRNA levels did not differ from non-diabetic subjects. After adjusting for confounding variables, diabetes was significantly associated with urinary ACE2 activity (p = 0.003) and protein levels (p<0.001), while female gender was associated with urinary mRNA levels for both ACE2 and ACE. These data indicate that urinary ACE2 is increased in renal transplant recipients with diabetes, possibly due to increased shedding from tubular cells. Urinary ACE2 could be a marker of renal renin-angiotensin system activation in these patients.


Asunto(s)
Diabetes Mellitus/orina , Trasplante de Riñón , Peptidil-Dipeptidasa A/orina , Adulto , Anciano , Angiotensina II/orina , Enzima Convertidora de Angiotensina 2 , Femenino , Humanos , Riñón/metabolismo , Masculino , Persona de Mediana Edad , ARN Mensajero/orina , Sistema Renina-Angiotensina/fisiología , Factores Sexuales
11.
Org Lett ; 12(9): 2048-51, 2010 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-20377270

RESUMEN

The domino coupling reaction of 1,1-dibromo-1-alkenes with triarylbismuth nucleophiles has been demonstrated to furnish disubstituted alkynes directly under catalytic palladium conditions. The couplings of triarylbismuths as multicoupling nucleophiles with 3 equiv of 1,1-dibromo-1-alkenes are very fast, affording high yields of alkynes in a short reaction time. Thus, an efficient domino process has been accomplished using 1,1-dibromo-1-alkenes as surrogates for internal alkyne synthesis in couplings with triarylbismuths in a one-pot operation.

12.
Food Addit Contam ; 23(10): 994-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16982521

RESUMEN

Rates of degradation of lambda-cyhalothrin and methomyl residues in grape are reported. The dissipation behavior of both insecticides followed first-order rate kinetics with similar patterns at standard and double-dose applications. Residues of lambda-cyhalothrin were lost with pre-harvest intervals (PHI) of 12.0-12.5 and 15.0-15.5 days, corresponding to the applications at 25 and 50 g a.i. ha-1, respectively. In the case of methomyl, residues were lost with PHI of 55.0 and 61.0 days, following applications at 1 and 2 kg a.i. ha-1, respectively. The PHI, recommended on the basis of the experimental results, was shown to be effective in minimizing residue load of these insecticides below their maximum residue limits (MRLs) in vineyard samples.


Asunto(s)
Contaminación de Alimentos/análisis , Metomil/metabolismo , Nitrilos/metabolismo , Residuos de Plaguicidas/metabolismo , Piretrinas/metabolismo , Vitis/metabolismo , Análisis de los Alimentos/métodos , Insecticidas/administración & dosificación , Insecticidas/metabolismo , Metomil/administración & dosificación , Nitrilos/administración & dosificación , Piretrinas/administración & dosificación , Factores de Tiempo
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