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1.
Biotechnol Appl Biochem ; 68(5): 1033-1043, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32918838

RESUMO

The protease was produced extracellularly in submerged fermentation by the yeast Rhodotorula oryzicola using different sources of nitrogen and maximum activity (6.54 × 10-3 U/mg) was obtained in medium containing 2% casein (w/v). Purification of the protease by gel filtration chromatography resulted in a 3.07-fold increase of specific protease activity. The optimal pH and temperature for enzyme activity were 6.51 and 63.04 °C, respectively. Incubation in the presence of some salts enhanced enzyme activity, which peaked under 0.01 M BaCl2 . The enzyme retained about 90% of enzymatic activity at temperatures 50-60 °C. The commercially available enzyme carriers evaluated, silica gel, Celite 545, and chitosan effectively immobilized the protease. The enzyme immobilized in Celite 545 retained 73.53% of the initial activity after 15 reuse cycles. These results are quite promising for large-scale production and immobilization of protease from R. oryzicola, as the high operational stability of the immobilized enzyme lowers production costs in biotechnological applications that require high enzymatic activity and stability under high temperatures.


Assuntos
Peptídeo Hidrolases/metabolismo , Rhodotorula/enzimologia , Biotecnologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Peptídeo Hidrolases/química , Temperatura
2.
Arch Anim Nutr ; 75(6): 465-473, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35253543

RESUMO

In this study, the effects of dietary fibre and types of indigestible markers (IM) on the apparent total tract digestibility (ATTD) of gross energy (GE) and nutrients as well as IM recovery in diets fed to growing pigs were investigated. A total of 30 barrows (initial body weight 40.5 ± 1.4 kg) were allotted to five experimental diets, based on a completely randomised block design, with body weight as a blocking factor. The five diets comprised a corn-soya bean meal basal diet, and four diets in which sugar beet pulp (SBP) or defatted rice bran (DFRB) partly replaced 10% or 20% of corn, soya bean meal and soya bean oil in the basal diet. All diets were formulated to contain two types of IM, namely 0.5% chromic oxide (Cr) and 1.0% celite as the source of acid-insoluble ash (AIA). Animals were subjected to a 7-d adaptation period, and their faeces were collected over a 5-d period using the total faecal collection (TC) method. Results showed that the AIA method determined similar ATTD of GE and nutrients as the TC method. Values of dietary nutrients determined via AIA and TC methods were significantly higher than those obtained by Cr (p < 0.05). The ATTD of GE and nutrients linearly decreased with an increased inclusion level of SBP or DFRB (p < 0.01), whereas recoveries of AIA and Cr were not affected by the aforementioned inclusions. Results from the faecal analysis revealed that AIA recovery (90.5%) was significantly higher than that of Cr (84.9%, p < 0.05), while diets with DFRB (91.3%) had significantly greater IM recovery rates than those with SBP (84.4%, p < 0.05). In conclusion, the type of dietary fibre, rather than the level, significantly affects IM recovery. Notably, AIA should be preferred to Cr when using the IM method to determine ATTD of GE and nutrients for diets in growing pigs.


Assuntos
Dieta , Digestão , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fibras na Dieta , Trato Gastrointestinal , Nutrientes , Suínos , Zea mays
3.
Food Technol Biotechnol ; 55(4): 542-552, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29540988

RESUMO

The lipophilic antioxidants, glyceryl ferulate and feruloyl glyceryl linoleate, were synthesized using lipase from Bacillus subtilis AKL 13. The extracellular lipase was produced by cultivation of the strain in modified minimal medium and the enzyme was recovered by fractionation at 80% ammonium salt saturation. The concentrated enzyme with the specific activity of (4647±66) U/mg was immobilized on Celite® 545 and crosslinked using glutaraldehyde. The prepared enzyme catalyst was used for esterification of ferulic and linoleic acids with glycerol separately in hexane butane solvent system at 50 °C and 3.144×g agitation. The maximum ester conversion of 94% of feruloyl glyceryl linoleate was achieved at 48 h, whereas only 35% of glyceryl ferulate was synthesized. The reaction products were characterized using RP-HPLC, FTIR, 1H NMR, 13C NMR and fluorescence spectrophotometry. The kinetic parameters of esterification reaction were determined according to ping-pong bi-bi model. The Km and υmax were found to be 69.37 and 3.46 mmol, and 0.387 and 1.02 mmol/(min·g) for glyceryl ferulate and feruloyl glyceryl linoleate, respectively. The kinetic parameters were simulated in MATLAB and the experimental data were in good agreement. Furthermore, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of the blend of feruloyl ester and palm oil was higher than of the plain palm oil and was closer to α-tocopherol.

4.
Microorganisms ; 11(8)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37630466

RESUMO

Ticks in the USA are the most important arthropod vector of microbes that cause human and animal disease. The blacklegged tick, Ixodes scapularis, the focus of this study, is able to transmit the bacteria that causes Lyme disease in humans in the USA. The main approach to tick control is the use of chemical acaricides and repellents, but known and potential tick resistance to these chemicals requires the discovery of new methods of control. Volcanic glass, Imergard, was recently developed to mimic the insecticide mode of action of the minerals from diatoms (diatomaceous earth, DE) for the control of malaria mosquitoes in Africa. However, studies on the use of these minerals for tick control are minimal. In a dipping assay, which was put into DE (Celite), the times of 50 and 90% death of adult female I. scapularis were 7.3 and 10.5 h, respectively. Our mimic of DE, Imergard, killed ticks in 6.7 and 11.2 h, respectively. In a choice-mortality assay, ticks moved onto a treated surface of Imergard and died at 11.2 and 15.8 h, respectively. Ticks had greater locomotor activity before death when treated by dipping for both Imergard and Celite versus the no-mineral control. The ticks after making contact with Imergard had the mineral covering most of their body surface shown by scanning electron microscopy with evidence of Imergard inside their respiratory system. Although the assumed mode of action of Imergard and Celite is dehydration, the minerals are not hygroscopic, there was no evidence of cuticle damage, and death occurred in as little as 2 h, suggesting minimal abrasive action of the cuticle. Semi-field and field studies are needed in the future to examine the practical use of Imergard and Celite for tick control, and studies need to examine their effect on tick breathing and respiratory retention of water.

5.
Environ Sci Pollut Res Int ; 30(23): 63535-63548, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37055688

RESUMO

The increasing usage of an important heavy metal chromium for industrial purposes, such as metallurgy, electroplating, leather tanning, and other fields, has contributed to an augmented level of hexavalent chromium (Cr(VI)) in watercourses negatively impacting the ecosystems and significantly making Cr(VI) pollution a serious environmental issue. In this regard, iron nanoparticles exhibited great reactivity in remediation of Cr(VI)-polluted waters and soils, but, the persistence and dispersion of the raw iron should be improved. Herein, this article utilized an environment-friendly celite as a modifying reagent and described the preparation of a novel composites namaly celite decorated iron nanoparticles (C-Fe0) and evaluation of C-Fe0 for the sequestration performance of Cr(VI) from aqueous solution. The results indicated that initial Cr(VI) concentration, adsorbent dosage, and especially solution pH are all critical factors to control C-Fe0 performance in Cr(VI) sequestration. We demonstrated that C-Fe0 could achieve a high Cr(VI) sequestration efficiency with an optimized adsorbent dosage. Fitness of the pseudo-second-order kinetics model with data indicated that adsorption was the rate-controlling step and chemical interaction controlled Cr(VI) sequestration on C-Fe0. The adsorption isotherm of Cr(VI) could be the best depicted by Langmuir model with a monolayer adsorption. The underlying sequestration path of Cr(VI) by C-Fe0 was then put forward, and the combined effect of adsorption and reduction implied the potentials of C-Fe0 in Cr(VI) removal.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Terra de Diatomáceas , Ferro , Ecossistema , Poluentes Químicos da Água/análise , Cromo/análise , Água , Adsorção , Cinética
6.
Biomolecules ; 13(8)2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37627300

RESUMO

Sand flies (Diptera: Psychodidae) serve as vectors for transmitting protozoan parasites, Leishmania spp., that cause the disease called leishmaniasis. The main approach to controlling sand flies is the use of chemical insecticides. The discovery of alternative methods for their control is needed because of potential health risks of chemical insecticides and development of sand fly resistance to these pesticides. The biomineral produced by diatoms (diatomaceous earth, DE; Celite) and a volcanic glass bio-mimic (Imergard) have been shown by our group to be efficacious against mosquitoes, filth flies, and ticks but never studied for the control of sand flies. In a modified World Health Organization cone test, 50% of adult Phlebotomus papatasi sand flies at 29 ± 1 °C, 55 ± 5% RH, and 12:12 LD, when exposed to Imergard and Celite, were dead in 13.08 and 7.57 h, respectively. Proof of concept was established for the use of these biominerals for sand fly and leishmaniasis disease control. Using a light source as an attractant to the minerals had no significant effect on the LT50, the time to 50% mortality. The LT50 at a higher relative humidity of 70 ± 5% increased to 20.91 and 20.56 h for Imergard and Celite, respectively, suggesting their mode of action was dehydration. Scanning electron microscopy of dead sand flies showed high coating levels of Celite only on the sides of the thorax and on the tarsi, suggesting an alternative mode of action for mechanical insecticides.


Assuntos
Inseticidas , Leishmania , Parasitos , Psychodidae , Animais , Terra de Diatomáceas , Minerais
7.
Insects ; 13(8)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35893027

RESUMO

Cases of Lyme disease in humans are on the rise in the United States and Canada. The vector of the bacteria that causes this disease is the blacklegged tick, Ixodes scapularis. Current control methods for I. scapularis mainly involve chemical acaricides. Unfortunately, ticks are developing resistance to these chemicals, and more and more, the public prefers non-toxic alternatives to chemical pesticides. We discovered that volcanic glass, ImergardTM WP, and other industrial minerals such as Celite 610 were efficacious mechanical insecticides against mosquitoes, filth flies, and agricultural pests. In this report, when 6-10- and 50-70-day old unfed I. scapularis nymphs were dipped for 1-2 s into Celite, the time to 50% mortality (LT50) was 66.8 and 81.7 min, respectively, at 30 °C and 50% relative humidity (RH). The LT50 was actually shorter at a higher 70% RH, 43.8 min. Scanning electron microscopy showed that the ticks were coated over most of their body surface, including partial to almost total coverage of the opening to their respiratory system. The other mechanical insecticide, Imergard, had similar efficacy against blacklegged unfed nymphs with an LT50 at 30 °C and 50% RH of 70.4 min. Although more research is needed, this study suggests that industrial minerals could be used as an alternative to chemical pesticides to control ticks and Lyme disease.

8.
MethodsX ; 9: 101653, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35313544

RESUMO

•To bypass the problem of viable but non-culturable bacteria that cannot be isolated by culturable methods would be to isolate DNA from bacterial cells concentrated from water samples used as a template for the polymerase chain reactions (PCR). DNA extraction protocol (Omar et al. 2010) was used as a foundation for extracting Escherichia coli DNA from water. The method combinations i.e., guanidium thiocyanate, celite and home-made spin column were chosen because it has been shown to be reliable, rapid, simple, and inexpensive for routine analysis in developing country settings.•The following optimizations were included: (a) Polycarbonate (Poly) was statistically compared with Polyether sulphone (PES), Nitrocellulose acetate (NA) and Nitrocellulose (NC) membranes; (b) Various housing containers for the membranes were tested: plastic/glass petri-dish, Falcon tubes, Ogreiner cryovials; (c) various solutions was tested to add to the membrane to remove cells from membranes; (d) celite was chosen to bind the DNA because it had a higher DNA binding capacity compared to silicon dioxide; (e) incubation times and rotation speed were tested when adding reagents.•The optimized in-house DNA extraction method was validated with environmental water samples, high (dam water) and low (borehole) bacterial load to determine upper and lower detection limits of the method.

9.
MethodsX ; 9: 101785, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855950

RESUMO

The COVID-19 pandemic lockdown created problems with importing of commercial kits resulting in extended turnaround times for consumable deliveries. One way to circumvent this was to use an inexpensive optimized in-house method for DNA extraction from water. • The DNA extraction methods were optimized on a 96-well plate using a semi-automated filtration system to increase the number of samples from 24 to 96 at a time in 2 h. The DNA extraction method optimizations included: (a) Guanidium thiocyanate method plus dilution series of celite to determine DNA binding capacity; (b) QIamp 96 Qiacube HT kit (Qiagen®); (c) Guanidium thiocyanate with the celite replaced with a binding buffer. • The in-house DNA extraction methods and adapted in-house DNA extraction method were compared to QIamp 96 Qiacube HT kit (Qiagen®), which is used on a 96-well semi-automated filtration system. The results showed maximum capacity of the 96-well filter plates was 400 µâ„“ broth (OD600 = 0.45 = 3.6 × 108 cells/mℓ) before the 96-well filters blocked. • When the methods were compared, there was no significant difference between the in-house DNA extraction method with 1:420 celite dilution (P-value = 0.126) and the adapted in-house method with binding buffer (P-value = 0.298) DNA yield or amplification of PCR products.

10.
Int J Biol Macromol ; 156: 1091-1103, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756471

RESUMO

Herein, λ-carrageenan-calcium phosphate (λ-Carr-Cp), carboxymethylcellulose (CMC) and celite 545 (Ce545) were used to functionalize sodium alginate bio-polymer (SAB). The water content in the wet beads was about 98%. Fourier Transform Infra-Red (FT-IR) showed that SAB@λ-Carr-Cp, SAB@CMC, and SAB@Ce545 could interact through intermolecular hydrogen and electrostatic interactions. Scanning Electron Microscopy (SEM) revealed that the morphology of the functionalized beads had a porous sheet structure. Energy Dispersive X-Ray (EDX) depicted that the peak intensity of the carbon element became more intense in the case of organic modification. The appearance of mineral elements characteristics of Ce545 (Si, Al) and Cp (P) proved the incorporation of these inorganic reagents into the alginate matrix. The data from batch adsorption experiments indicated that the adsorption of methylene blue (MB) depended on pH, time, temperature, and dye concentration. At equilibrium, the adsorption capacities followed the order: SAB@Ce545 (7.5 mg g-1 wet) > SAB@λ-carr-Cp (6.8 mg g-1 wet) > SAB@CMC (6.5 mg g-1 wet) > SAB (5.77 mg g-1 wet). Kinetic data agreed with pseudo second-order suggesting chemi-sorption mechanism. The equilibrium data fitted for Freundlich. In summary, this provided assembly strategy could offer a new research opportunity for developing functionalized biopolymers with new functions and potential applications.


Assuntos
Alginatos/química , Biopolímeros/química , Fosfatos de Cálcio/química , Carboximetilcelulose Sódica/química , Chondrus/química , Terra de Diatomáceas/química , Géis/química , Azul de Metileno/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água/química
11.
JA Clin Rep ; 6(1): 3, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-32026037

RESUMO

BACKGROUND: Heparin-induced thrombocytopenia type II (HIT II) is a rare, immune-mediated complication of heparin therapy and can cause life-threatening thromboembolism. However, perioperative anticoagulation therapy for patients with a complication of HIT II has not been established. CASE PRESENTATION: A 6-year-old boy with tetralogy of Fallot underwent radical intracardiac repair with administration of argatroban at 1 year old due to positive HIT antibody. Reoperation was scheduled for pulmonary valve insufficiency, using argatroban and nafamostat mesilate as anticoagulants. Argatroban has a long onset time and the activated coagulation time (ACT) requires 7-26 h to return to the preadministration level, making hemorrhage control difficult, while half-life of nafamostat mesilate is shorter than that of argatroban. Celite ACT reflects the effects of both argatroban and nafamostat mesilate, but kaolin ACT reflects only the effect of argatroban. Due to the early termination of argatroban administration based on Celite and kaolin ACTs, ACT recovered to ≤ 200 s at 5 h after the end of argatroban administration. CONCLUSION: Celite and kaolin ACTs can be used as markers to obtain close control of the required dose of argatroban in combination with nafamostat mesilate for the management of HIT II patients.

12.
Food Chem ; 312: 126000, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31884299

RESUMO

The physico-chemical, textural and color parameters and fluorescence spectra of aromatic amino acids and nucleic acids (AAA + NA), tryptophan residues, nicotinamide adenine dinucleotide (NADH) and vitamin A were scanned on sturgeon samples kept at 4 °C up to 12 days. Using the principal component analysis (PCA), the riboflavin and NADH spectra allowed clear differentiation between sturgeon samples according to their storage time. The best result was obtained by applying the common components and specific weights analysis (CCSWA) to the riboflavin and NADH data tables since better differentiation was achieved between the 4 group sturgeon samples aged: 2 days; 5, 6 and 7 days; 8 and 9 days and 12 days. The proposed methodology demonstrates the ability of CCSWA to evaluate sturgeon freshness level according to their storage time.


Assuntos
Peixes , Animais , Fenômenos Químicos , Temperatura Baixa , Cor , Vitamina A/análise
13.
Food Chem ; 275: 322-332, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724203

RESUMO

The potentialities of front-face fluorescence (FFF) and mid-infrared (MIR) spectroscopies coupled with partial least square regression (PLSR) were compared to predict the lipid oxidation of pound cakes. The level of lipid oxidation in pound cakes determined using classical methods showed some changes. Similarly, the fluorescence emission (305-490 nm) and excitation (252-390 nm) spectra and MIR spectra scanned in the 4000-700 cm-1 region showed some changes in pound cakes as a function of both storage time and the type of oil used in the formulation. The application of PLSR to the MIR spectra, provided excellent predictive results for free fatty acid (R2 = 0.97) and peroxide values (R2 = 0.87). Similar results were obtained from both tryptophan and MIR spectra for the prediction of TOTOX (R2 > 0.86) demonstrating the efficiency of the MIR and FFF spectroscopies to qualify and quantify the level of lipid oxidation in pound cakes.


Assuntos
Pão , Armazenamento de Alimentos/métodos , Lipídeos/química , Espectrometria de Fluorescência/métodos , Espectrofotometria Infravermelho/métodos , Análise dos Mínimos Quadrados , Oxirredução , Óleo de Palmeira , Óleo de Brassica napus , Espectrometria de Fluorescência/estatística & dados numéricos , Espectrofotometria Infravermelho/estatística & dados numéricos , Triptofano/química , Vitamina A/química
14.
J Biosci Bioeng ; 126(2): 176-182, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29627319

RESUMO

Glucose isomerase (GI) responsible for catalyzing the isomerization from d-glucose to d-fructose, was an important enzyme for producing high fructose corn syrup (HFCS). In a quest to prepare HFCS at elevated temperature and facilitate enzymatic recovery, an effective procedure for whole cell immobilization of refractory Thermus oshimai glucose isomerase (ToGI) onto Celite 545 using tris(hydroxymethyl)phosphine (THP) as crosslinker was established. The immobilized biocatalyst showed an activity of approximate 127.3 U/(g·immobilized product) via optimization in terms of cells loading, crosslinker concentration and crosslinking time. The pH optimum of the immobilized biocatalyst was displaced from pH 8.0 of native enzyme to neutral pH 7.0. Compared with conventional glutaraldehyde (GLU)-immobilized cells, it possessed the enhanced thermostability with 70.1% residual activity retaining after incubation at 90°C for 72 h. Moreover, the THP-immobilized biocatalyst exhibited superior operational stability, in which it retained 85.8% of initial activity after 15 batches of bioconversion at 85°C. This study paved a way for reducing catalysis cost for upscale preparation of HFCS with higher d-fructose concentration.


Assuntos
Aldose-Cetose Isomerases , Enzimas Imobilizadas , Xarope de Milho Rico em Frutose/metabolismo , Temperatura Alta , Fosfinas/química , Aldose-Cetose Isomerases/química , Aldose-Cetose Isomerases/metabolismo , Reagentes de Ligações Cruzadas/química , Reagentes de Ligações Cruzadas/farmacologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Frutose/química , Frutose/metabolismo , Glucose/química , Glucose/metabolismo , Xarope de Milho Rico em Frutose/química , Concentração de Íons de Hidrogênio , Fosfinas/metabolismo , Fosfinas/farmacologia
15.
3 Biotech ; 6(2): 183, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28330255

RESUMO

Ascorbyl palmitate was synthesized using a Celite-immobilized commercial lipase (Lipolase 100L) in dimethylsulfoxide (DMSO) as an organic solvent system. Lipase immobilized by surface adsorption onto Celite 545 matrix and subsequently exposed to 1 % glutaraldehyde showed 75 % binding of protein. The Celite-bound lipase was optimally active at 75 °C and pH 8.5 under shaking and showed maximum hydrolytic activity toward p-NPP as a substrate. The bound lipase was found to be stimulated only in the presence of Al3+ and EDTA. All surfactants (Tween-20, Tween-80 and Triton X-100) had an inhibitory effect on lipase activity. The optimization of various reaction conditions of ascorbyl palmitate was achieved considering one factor at a time. The esterification of ascorbic acid and palmitic acid was carried out with 1 M ascorbic acid and 2.5 M palmitic acid in DMSO at 75 °C for 18 h under shaking (120 rpm). Molecular sieves had an important effect on the ester synthesis resulting in an enhanced yield. The by-product (H2O) produced in the reaction was scavenged by the molecular sieves (20 mg/ml) added in the reaction mixture which enhanced the ester yield to 80 %. The characterization of synthesized ester was done through FTIR spectroscopy.

16.
J Virol Methods ; 228: 31-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26562058

RESUMO

The collection of waterborne pathogen occurrence data often requires the concentration of microbes from large volumes of water due to the low number of microorganisms that are typically present in environmental and drinking waters. Hollow-fiber ultrafiltration (HFUF) has shown promise in the recovery of various microorganisms. This study has demonstrated that the HFUF primary concentration method is effective at recovering bacteriophage φX174, poliovirus, enterovirus 70, echovirus 7, coxsackievirus B4 and adenovirus 41 from large volumes of tap and river water with an average recovery of all viruses of 73.4% and 81.0%, respectively. This study also evaluated an effective secondary concentration method using celite for the recovery of bacteriophage and enteric viruses tested from HFUF concentrates of both matrices. Overall, the complete concentration method (HFUF primary concentration plus celite secondary concentration) resulted in a concentration factor of 3333 and average recoveries for all viruses from tap and river waters of 60.6% and 60.0%, respectively.


Assuntos
Adenoviridae/isolamento & purificação , Bacteriófagos/isolamento & purificação , Terra de Diatomáceas , Enterovirus/isolamento & purificação , Microbiologia da Água , Bacteriófago phi X 174/isolamento & purificação , Água Potável/virologia , Água Doce/virologia , Poliovirus/isolamento & purificação , Ultrafiltração/instrumentação , Ultrafiltração/métodos , Purificação da Água/instrumentação , Purificação da Água/métodos
17.
Bioresour Technol ; 188: 214-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25670399

RESUMO

Novel lipase from model mushroom Schizophyllum commune strain ISTL04 produced by solid state fermentation of Leucaena leucocephala seeds, was immobilized onto Celite for enzymatic FAMEs production from cyanobacterial endolith Leptolyngbya ISTCY101. The isolate showed vigorous growth and produced remarkable lipase activity of 146.5 U g(-1) dry solid substrate, without any external lipase inducer. Single-factor experiments were carried out to study the effects of various reaction parameters on the FAMEs yield. The best conditions for enzymatic transesterification as revealed by the results were: 1:3 oil to methanol molar ratio, added at 3h intervals, 12% water content, 1581.5 U g(-1) immobilized lipase, temperature 45 °C, and time 24h. Under these conditions, the maximum FAMEs yield reached 94%. The immobilized lipase was able to produce >90% of the relative FAMEs yield after four repeated transesterification cycles. This immobilized lipase exhibited potential for application in biodiesel industry.


Assuntos
Enzimas Imobilizadas/química , Ésteres/química , Ácidos Graxos/biossíntese , Lipase/química , Schizophyllum/enzimologia , Agaricales/enzimologia , Biocombustíveis , Biotecnologia , Cromatografia Líquida de Alta Pressão , Cianobactérias/química , Terra de Diatomáceas/química , Esterificação , Fermentação , Microbiologia Industrial , Metanol/química , Óleos/química , Temperatura , Água/química
18.
Mycobiology ; 42(3): 305-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25346612

RESUMO

We investigated a novel process for production of ethanol from glycerol using the yeast Pachysolen tannophilus. After optimization of the fermentation medium, repeated-batch flask culture was performed over a period of 378 hr using yeast cells immobilized on Celite. Our results indicated that the use of Celite for immobilization of P. tannophilus was a practical approach for ethanol production from glycerol, and should be suitable for industrial ethanol production.

19.
J Virol Methods ; 193(1): 140-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23727118

RESUMO

Enteroviruses, noroviruses and adenoviruses are among the most common viruses infecting humans worldwide. These viruses are shed in the feces of infected individuals and can accumulate in wastewater, making wastewater a source of a potentially diverse group of enteric viruses. In this study, two procedures were evaluated to concentrate noroviruses, adenoviruses and enteroviruses from primary effluent of wastewater. In the first procedure, indigenous enteroviruses, noroviruses and adenoviruses were concentrated using celite (diatomaceous earth) followed by centrifugation through a 30K MWCO filter and nucleic acid extraction. The second procedure used celite concentration followed by nucleic acid extraction only. Virus quantities were measured using qPCR. A second set of primary effluent samples were seeded with Coxsackievirus A7, Coxsackievirus B1, poliovirus 1 or enterovirus 70 before concentration and processed through both procedures for recovery evaluation of enterovirus species representatives. The pairing of the single step extraction procedure with the celite concentration process resulted in 47-98% recovery of examined viruses, while the celite concentration process plus additional centrifugal concentration before nucleic acid extraction showed reduced recovery (14-47%). The celite concentration process followed by a large volume nucleic acid extraction technique proved to be an effective procedure for recovering these important human pathogens from wastewater.


Assuntos
Adenovírus Humanos/isolamento & purificação , Terra de Diatomáceas/química , Enterovirus/isolamento & purificação , Norovirus/isolamento & purificação , Virologia/métodos , Águas Residuárias/virologia , Centrifugação/métodos , Filtração/métodos , Humanos , Ácidos Nucleicos/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real
20.
J Virol Methods ; 193(2): 284-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23796954

RESUMO

Currently, the U.S. Environmental Protection Agency's Information Collection Rule (ICR) for the primary concentration of viruses from drinking and surface waters uses the 1MDS filter, but a more cost effective option, the NanoCeram® filter, has been shown to recover comparable levels of enterovirus and norovirus from both matrices. In order to achieve the highest viral recoveries, filtration methods require the identification of optimal concentration conditions that are unique for each virus type. This study evaluated the effectiveness of 1MDS and NanoCeram filters in recovering adenovirus (AdV) 40 and 41 from tap water, and optimized two secondary concentration procedures the celite and organic flocculation method. Adjustments in pH were made to both virus elution solutions and sample matrices to determine which resulted in higher virus recovery. Samples were analyzed by quantitative PCR (qPCR) and Most Probable Number (MPN) techniques and AdV recoveries were determined by comparing levels of virus in sample concentrates to that in the initial input. The recovery of adenovirus was highest for samples in unconditioned tap water (pH 8) using the 1MDS filter and celite for secondary concentration. Elution buffer containing 0.1% sodium polyphosphate at pH 10.0 was determined to be most effective overall for both AdV types. Under these conditions, the average recovery for AdV40 and 41 was 49% and 60%, respectively. By optimizing secondary elution steps, AdV recovery from tap water could be improved at least two-fold compared to the currently used methodology. Identification of the optimal concentration conditions for human AdV (HAdV) is important for timely and sensitive detection of these viruses from both surface and drinking waters.


Assuntos
Adenovírus Humanos/isolamento & purificação , Água Potável/virologia , Filtração/métodos , Virologia/métodos , Adsorção , Terra de Diatomáceas/química , Floculação , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Estados Unidos , Carga Viral
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