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1.
Bioresour Technol ; 380: 129065, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37080440

ABSTRACT

Sun hemp fibers are natural fibers obtained from plants grown in India and nearby countries. It is lignocellulosic biomass having the complex structure of hemicelluloses, cellulose and lignin. Chemical treatment of natural fibers is in practice to enhance the properties being used as reinforcement. Alkaline-treated fiber was sampled and thermal stability along with kinetic parameters was assessed with thermo gravimetric data at heating rates 10, 20 and 30 °C/min using four model-free methods Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO), Friedman (FM), Starink (STAR) along with Distributed activation energy model (DAEM) to calculate pre-exponential factor. The calculated activation energy Ea by these model-free methods were in the range of 93.3-104.8 kJ/mol and pre-exponential factor (A) was observed between the range 46.6 x103-90.5 x106/min by the DAEM method. The standard deviation (σ) calculated from average activation energy using all four methods was 4.5 kJ/mol, which showed the consistency in the methods employed to determine the activation energy of sun hemp.


Subject(s)
Cannabis , Biomass , Cellulose , Physics , Lignin , Kinetics , Thermogravimetry
2.
Neuromodulation ; 23(7): 922-925, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32691464

ABSTRACT

OBJECTIVE: The healthcare and social disruption caused by the COVID-19 pandemic could pose significant risk to patients with intrathecal pump (ITP) who may miss refill or replacement appointments. In some cases, this could be life-threatening. We designed and piloted a novel refill protocol to assess its efficacy and safety. MATERIALS AND METHODS: Screening of our ITP database for patients most at risk of harm was conducted. These patients were risk-assessed for COVID-19 infection and were enrolled in a protocol to optimize the safety and efficiency of their pump replacement or refill. RESULTS: Of note, 31 of 51 database patients were deemed to be high risk of ITP failure during the pandemic. Thirty patients were successfully refilled with only one patient refusing to leave their house for refill. There were no significant adverse outcomes. CONCLUSION: Our protocol offers a safe and efficient pathway for ITP management during a pandemic.


Subject(s)
COVID-19 , Delivery of Health Care , Infusion Pumps, Implantable , Injections, Spinal , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , SARS-CoV-2 , Young Adult
3.
Bioresour Technol ; 279: 385-392, 2019 May.
Article in English | MEDLINE | ID: mdl-30685132

ABSTRACT

It is envisaged that the utilization of lignocellulosic biomass for ethanol production for transport sector, would make cellulases the most demanded industrial enzyme. The greatest potential of cellulolytic enzymes lies in ethanol production from biomass by enzymatic hydrolysis of cellulose but low thermostability and low titer of cellulase production resulting into high cost of the enzyme which is the major set-back. A number of research groups are working on cellulase to improve its thermostability so as to be able to perform hydrolysis at elevated temperatures which would eventually increase the efficiency of cellulose hydrolysis. The technologies developed from lignocellulosic biomass via cellulose hydrolysis promise environmental and economical sustainability in the long run along with non-dependence on nonrenewable energy source. This review deals with the important sources of thermostable cellulases, mechanism, its regulation, strategies to enhance the thermostability further with respect to its importance for biofuel applications.


Subject(s)
Cellulases/metabolism , Animals , Biofuels , Biomass , Cellulose/metabolism , Enzyme Stability , Lignin/metabolism
4.
Bioresour Technol ; 246: 110-122, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28863990

ABSTRACT

In recent years, there has been a significant interest on biochar for various environmental applications, e.g., pollutants removal, carbon sequestration, and soil amelioration. Biochar has several unique properties, which makes it an efficient, cost-effective and environmentally-friendly material for diverse contaminants removal. The variability in physicochemical properties (e.g., surface area, microporosity, and pH) provides an avenue for biochar to maximize its efficacy to targeted applications. This review aims to highlight the vital role of surface architecture of biochar in different environmental applications. Particularly, it provides a critical review of current research updates related to the pollutants interaction with surface functional groups of biochars and the effect of the parameters variability on biochar attributes pertinent to specific pollutants removal, involved mechanisms, and competence for these removals. Moreover, future research directions of biochar research are also discussed.


Subject(s)
Charcoal , Adsorption , Soil , Soil Pollutants
5.
J Proteome Res ; 14(8): 3051-67, 2015 Aug 07.
Article in English | MEDLINE | ID: mdl-25997359

ABSTRACT

Chlamydomonas reinhardtii was batch-cultured for 12 days under continuous illumination to investigate nitrogen uptake and metabolic responses to wastewater processing. Our approach compared two conditions: (1) artificial wastewater containing nitrate and ammonia and (2) nutrient-sufficient control containing nitrate as sole form of nitrogen. Treatments did not differ in final biomass; however, comparison of group proteomes revealed significant differences. Label-free shotgun proteomic analysis identified 2358 proteins, of which 92 were significantly differentially abundant. Wastewater cells showed higher relative abundances of photosynthetic antenna proteins, enzymes related to carbon fixation, and biosynthesis of amino acids and secondary metabolites. Control cells showed higher abundances of enzymes and proteins related to nitrogen metabolism and assimilation, synthesis and utilization of starch, amino acid recycling, evidence of oxidative stress, and little lipid biosynthesis. This study of the eukaryotic microalgal proteome response to nitrogen source, availability, and switching highlights tightly controlled pathways essential to the maintenance of culture health and productivity in concert with light absorption and carbon assimilation. Enriched pathways in artificial wastewater, notably, photosynthetic carbon fixation and biosynthesis of plant hormones, and those in nitrate only control, most notably, nitrogen, amino acid, and starch metabolism, represent potential targets for genetic improvement requiring targeted elucidation.


Subject(s)
Algal Proteins/metabolism , Chlamydomonas reinhardtii/metabolism , Microalgae/metabolism , Proteome/metabolism , Proteomics/methods , Wastewater/chemistry , Amino Acids/metabolism , Ammonia/metabolism , Ammonia/pharmacology , Biodegradation, Environmental , Biomass , Carbon Cycle/drug effects , Chlamydomonas reinhardtii/drug effects , Chlamydomonas reinhardtii/growth & development , Chromatography, Liquid/methods , Culture Media/chemistry , Culture Media/metabolism , Culture Media/pharmacology , Microalgae/drug effects , Microalgae/growth & development , Nitrates/metabolism , Nitrates/pharmacology , Nitrogen/metabolism , Starch/metabolism , Tandem Mass Spectrometry/methods , Waste Disposal, Fluid/methods
6.
Appl Biochem Biotechnol ; 162(1): 166-80, 2010 Sep.
Article in English | MEDLINE | ID: mdl-19669939

ABSTRACT

Probiotic has modernized the current dietetic sense with novel therapeutic and nutritional benefits to the consumers. The presence of bile salt hydrolase (BSH) in probiotics renders them more tolerant to bile salts, which also helps to reduce the blood cholesterol level of the host. This review focuses on the occurrence of bile salt hydrolase among probiotics and its characterization, importance, applications, and genetics involved with recent updates. Research on bile salt hydrolase is still in its infancy. The current perspective reveals a huge market potential of probiotics with bile salt hydrolase. Intensive research in this field is desired to resolve some of the lacunae.


Subject(s)
Amidohydrolases , Probiotics , Amidohydrolases/chemistry , Amidohydrolases/genetics , Amidohydrolases/metabolism , Amidohydrolases/pharmacology , Amino Acid Sequence , Animals , Gene Expression Regulation, Enzymologic , Genomics , Health , Humans
7.
Appl Biochem Biotechnol ; 160(1): 140-55, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19280126

ABSTRACT

Siderophoregenic Bacillus strain DET9 has been selectively isolated from dairy waste. It was evaluated for probiotic characteristics and susceptibility pattern against antibiotics. Its spores showed excellent tolerance to simulated gastrointestinal tract conditions and exhibited antimicrobial activity against organisms such as Escherichia coli, Micrococcus flavus, and Staphylococcus aureus. Its susceptibility to antibiotics reduces the prospect to donate resistance determinants if administered in the form of probiotic preparations. It was observed to produce approximately 60 mg/l catecholate type of siderophore under iron stressed conditions, identified as a 2,3-dihydroxy benzoic acid by high-performance liquid chromatography, infrared spectroscopy, nuclear magnetic resonance, and mass spectral analysis. Partial 16S-rRNA gene sequencing analysis shows that the isolate exhibited homology with Bacillus thuringiensis and Bacillus weihenstephanensis, whereas biochemical characterization revealed its novelty. DET9 exhibited no mortality of fishes in a 60-day trial, when fishes (surfi tetra) were challenged up to 100 ppm cell concentration, with their daily diet.


Subject(s)
Bacillus/isolation & purification , Bacillus/physiology , Dairy Products/microbiology , Industrial Waste , Probiotics/metabolism , Siderophores/biosynthesis , Animals , Anti-Bacterial Agents/pharmacology , Bacillus/drug effects , Bacillus/genetics , Bacterial Adhesion , Base Sequence , Bile Acids and Salts/pharmacology , Catalase/metabolism , Diet , Fishes/microbiology , Fishes/physiology , Gastric Acid , Hemolysis , Humans , Hydrophobic and Hydrophilic Interactions , Iron/metabolism , Molecular Sequence Data , Phylogeny , Probiotics/administration & dosage , Spores, Bacterial/genetics , Spores, Bacterial/metabolism , Spores, Bacterial/physiology
8.
Bioresour Technol ; 100(1): 368-73, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18585911

ABSTRACT

The aim of the present study was to characterize the probiotic qualities of Bacillus isolates and study their siderophore prior to possible siderophoregenic probiotic application for iron nutrition in animals and humans. Bacillus strains were selectively isolated from dairy waste and mango pulp waste. Best two siderophore positive isolates, JHT3 and DET6 showed high homology with Bacillus megaterium (98%) and B. subtilis (99%), respectively, using partial 16S-rRNA sequencing and biochemical characterization. These isolates produced catecholate type of siderophore under iron stressed conditions and were screened for probiotic properties as per WHO and FAO guidelines. Spores of these strains showed excellent tolerance in partially simulated gastrointestinal tract conditions and exhibited antimicrobial activity against organisms such as Staphylococcus aureus, Micrococcus flavus and Escherichia coli. Importantly, these isolates were susceptible to the most of the antibiotics tested, in conflict that they would not donate resistance determinants if administered in the form of probiotic preparations.


Subject(s)
Bacillus/chemistry , Bacillus/isolation & purification , Catechols/chemistry , Catechols/isolation & purification , Probiotics/chemistry , Siderophores/chemistry , Siderophores/isolation & purification , Bacillus/classification , Probiotics/isolation & purification , Species Specificity
9.
Braz. arch. biol. technol ; 47(2): 309-317, June 2004. ilus, tab, graf
Article in English | LILACS | ID: lil-362293

ABSTRACT

Fermentação no Estado Sólido foi empregada na produção de alfa-amilase usando Aspergillus niger. Diferentes tipos de torta foram utilizadas, como torta de óleo de coco (COC), torta de de óleo de amendoim (GOC) torta de óleo de sesamo (SOC), torta de palma (PKC) e torta de óleo de oliva (OOC) foram selecionadas para serem usadas como substratos para produção de enzima e comparadas com o farelo de trigo (WB), GOC foi escolhido por ser o que produziu maiores concentrações de enzima. A combinação WB e GOC (1:1) resultou em maiores títulos da enzima quando em comparação com os substratos individuais. A máxima concentração de enzima (9196 U/ gms) foi obtida quando a FES foi conduzida utilizando WB + GOC, com umidade de 64% e suplementada com lactose e nitrato de amônia (1% cada) a 300C por 72 horas utilizando 2 mL de uma suspensão de esporo (6x107sporos/ml). A purificação parcial da enzima usando frações de sulfato de amônio resultou num aumento de 2-4 vezes o aumento da atividade. A enzima apresentou um peso molecular de 68 Kda pelo SDS_PAGE. Exceto Mn, todos os outros íons metálicos como Ca, K, Na, Mg são inibitórios na produção da enzima.

10.
Bioresour Technol ; 93(2): 169-74, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15051078

ABSTRACT

Solid-state fermentation (SSF) was carried out using coconut oil cake (COC) as substrate for the production of alpha-amylase using a fungal culture of Aspergillus oryzae. Raw COC supported the growth of the culture, resulting in the production of 1372 U/gds alpha-amylase in 24 h. Process optimization using a single parameter mode showed enhanced enzyme titre, which was maximum (1827 U/gds) when SSF was carried out at 30 degrees C for 72 h using a substrate with 68% initial moisture. Supplementation with glucose and starch further enhanced enzyme titre, which was maximum (1911 U/gds) with 0.5% starch. However, maltose inhibited the enzyme production. Studies on the effect of addition of external organic and inorganic nitrogenous compounds further showed a positive impact on enzyme synthesis by the culture. Increase of 1.7-fold in the enzyme activity (3388 U/gds) was obtained when peptone at 1% concentration was added to the fermentation medium. The enzyme production was growth-related, the activity being the maximum when the fungal biomass was at its peak at 72 h. Use of COC as raw material for enzyme synthesis could be of great commercial significance. To the best of our knowledge this is the first report on alpha-amylase production using COC in SSF.


Subject(s)
Aspergillus oryzae/metabolism , Bioreactors , Plant Oils/metabolism , alpha-Amylases/biosynthesis , Biomass , Coconut Oil , Fermentation , Glucose , Kinetics , Maltose , Starch , Temperature , Time Factors
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