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1.
Braz J Biol ; 84: e262459, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35830132

RESUMEN

Evaluate the effect of ascorbic acid application and coexistence of Mycorrhiza fungus and Azospirillium on basil (Ocimum basilicum L.) under drought stress. This experiment was performed as a split factorial in a randomized complete block design with three replications in the crop year 2017-2018 in Shahriar, Iran. In this experiment, irrigation was the main factor in three levels, including drought stress based on 40-70-100 mm from the evaporation pan of class A. Biofertilizer including growth-promoting bacteria (Azospirillium) and mycorrhiza fungus in four levels, including a(Non-consumption) B (Seeds of growth-promoting bacteria (Azospirillium)) C (Consumption of mycorrhiza fungus as seeds) D (Concomitant use of growth-promoting bacteria Azospirillium with mycorrhiza fungi as seeds) and ascorbic acid in two levels of foliar application, including A (Absence Application of ascorbic acid) and B (Application of ascorbic acid (two days after irrigation treatment)) was considered as a factorial factor. The results showed that the highest biological yield was obtained in drought stress of 40 mm and application of biological fertilizers in the form of mycorrhiza application with an average of 3307.1 kg/ha, which was about 70% more than 100 mm evaporation stress and no application of biological fertilizer. The use of ascorbic acid under drought stress conditions improved by 10%, the essential oil using ascorbic acid evaporated under drought stress conditions of 100 mm. As a general conclusion, the use of ascorbic acid and Mycorrhiza + Azospirillium biological fertilizer improved the quantitative and qualitative characteristics of basil under drought stress.


Asunto(s)
Fertilizantes , Ocimum basilicum , Ácido Ascórbico/farmacología , Sequías , Semillas
2.
Meat Sci ; 153: 2-8, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30856549

RESUMEN

Twenty-four Mahabadi goat kids (5-6 months of age) were used to evaluate the effects of feeding olive leaves (OL) on performance, carcass traits and antioxidant status. The kids received three dietary treatments for 84 d with three levels of OL: 0 (control), 7.5 (OL7.5) and 15 (OL15) % (DM basis). Supplementation with OL had no effects on kid performance (P > 0.05). Total antioxidant capacity (TAC) was increased and malondialdehyde (MDA) concentration was decreased in plasma blood (P < 0.01) and Longissimus lumborum (LL) muscle (days 1, 4, 7 and 10) of kids (P < 0.01) with increasing level of OL in diet. The activity of glutathione peroxidase (GSH-Px) in LL muscle was increased (P < 0.05) in OL15 fed kids compared with control group. Also, glucose content of serum was decreased by adding OL to kid diets (P < 0.01). Finally, inclusion of OL to kid diets resulted in similar growth performance compared to alfalfa feeding, and improved the antioxidative potential of LL muscle.


Asunto(s)
Alimentación Animal/análisis , Cabras/crecimiento & desarrollo , Olea , Animales , Antioxidantes/análisis , Glucemia , Dieta , Masculino , Malondialdehído/análisis , Carne , Músculo Esquelético/química , Hojas de la Planta
3.
J Appl Microbiol ; 126(6): 1761-1771, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30916880

RESUMEN

AIM: The effect of heavy metals presence on the decolourization of Reactive Black 5 by Pseudomonas aeruginosa was evaluated. METHODS AND RESULTS: In the current study, a newly isolated strain identified as P. aeruginosa strain Gb 30 was selected for its ability to remove high concentration of Reactive Black 5 and resistance to several heavy metals (Cu2+ >Zn2+ >Cd2+ >Cr6+ ). Strain Gb30 was used to assess the effect of heavy metals presence on RB5 decolourization. The strain growth exhibited different responses at a fixed concentration of EC50 (10 h) for each heavy metal. The addition of Zn2+ and Cd2+ had no effect on decolourization yield after 24 h of incubation, whereas Cr6+ and Cu2+ ions reduced decolourization up to 17%. In order to understand the relationship between heavy metals contamination and decolourization, experimental data relating the initial decolourization rate of RB5 to the concentrations of single and associated heavy metals were fitted to three different inhibition kinetic models. CONCLUSIONS: In this study, we showed that P. aeruginosa strain Gb30 could be used for dye removal even at high concentrations of heavy metals. The developed models could provide basic information that may help for the best management of the bacteria-mediated decolourization process at the industrial scale. SIGNIFICANCE AND IMPACT OF THE STUDY: This study opens new directions for the management of textile industry wastewaters containing dyes and heavy metals using bioaugmentation by P. aeruginosa strain Gb30.


Asunto(s)
Colorantes/metabolismo , Metales Pesados/metabolismo , Modelos Químicos , Naftalenosulfonatos/metabolismo , Pseudomonas aeruginosa/metabolismo , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Farmacorresistencia Bacteriana , Metales Pesados/química , Modelos Teóricos , Industria Textil , Aguas Residuales/química
4.
Appl Radiat Isot ; 146: 90-98, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30763820

RESUMEN

A deuterium-deuterium (D-D) neutron generator facility has been developed with a wide range of applications in mind. D-D neutron generators provide a safe, convenient, and low-cost solution for the production of thermal, epithermal, and fast neutrons for laboratory and industrial applications. The regulatory burden for operating one of these generators is small as it contains no radioactive material and produces no radiation when turned off. One such D-D neutron generator has been installed at the National Center of Nuclear Sciences and Technologies (CNSTN). This generator produces 2.45 MeV fast neutrons with a maximum yield of 1010.n/s. To maintain a strong radiation safety program, detailed knowledge of the radiation dose rates around the neutron generator is crucial for ensuring the radiological protection of the personnel involved with its operation. This work describes the Monte Carlo calculations and experimental measurements carried out in the Neutron Generator facility of the CNSTN. The adequacy of the radiation shielding of the facility was verified by measuring the neutron and gamma dose rates at various locations inside and outside the neutron generator hall during operation and comparing them with Monte Carlo calculations. Measured and calculated dose rates were in agreement to better than 20% depending on location. The operation of this neutron facility will provide a suitable neutron source for future basic and applied research.

5.
Adv Food Nutr Res ; 81: 109-159, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28317603

RESUMEN

In recent years, a great deal of interest has been expressed regarding the production, characterization, and applications of protein hydrolysates and food-derived biopeptides due to their numerous beneficial health effects. In this regard, research is mainly focused on investigating the therapeutic potential of these natural compounds. Based on their amino acids composition, sequences, hydrophobicity, and length, peptides released from food proteins, beyond their nutritional properties, can exhibit various biological activities including antihypertensive, antioxidative, antithrombotic, hypoglycemic, hypocholesterolemic, and antibacterial activities among others. Protein hydrolysates are essentially produced by enzymatic hydrolysis of whole protein sources by appropriate proteolytic enzymes under controlled conditions, followed by posthydrolysis processing to isolate desired and potent bioactive peptides from a complex mixture of active and inactive peptides. Therefore, because of their human health potential and safety profiles, protein hydrolysates and biopeptides may be used as ingredients in functional foods and pharmaceuticals to improve human health and prevent diseases. In this review, we have focused on the major variables influencing the enzymatic process of protein hydrolysates production. The biological properties of protein hydrolysates will be described as well as their applications in foods and health benefits.


Asunto(s)
Análisis de los Alimentos , Péptidos/química , Hidrolisados de Proteína/química , Dieta , Alimentos Funcionales , Humanos
6.
Cancer Radiother ; 21(1): 45-50, 2017 Feb.
Artículo en Francés | MEDLINE | ID: mdl-28223032

RESUMEN

PURPOSE: To identify retrospectively prognostic factors of primary breast sarcoma and review its treatment modalities. MATERIALS AND METHODS: This is a descriptive study on 30 cases of primary breast sarcoma. We carried out a univariate and multivariate analysis correlating clinical, pathological and therapeutic parameters with disease-free survival and overall survival. RESULTS: The mean age was 46.8 years. The mean tumour size was 10cm. The 30 cases were 18 phyllodes sarcomas, eight angiosarcomas, three liposarcomas and a case of granulocytic sarcoma. Sixteen patients had adjuvant radiotherapy and only seven patients received adjuvant chemotherapy. The median follow-up was 64 months. Overall survival rates at 3 and 5 years were 49.1% and 33.7%. Disease-free survival rates at 3 and 5 years were 22.8% and 15.2% respectively. The analytical study of the following parameters: tumour size and presence or absence of node or distant metastases, showed no correlation with overall survival nor with disease-free survival. Furthermore, adjuvant radiotherapy did not improve overall survival (P=0.298; hazard ratio [HR]=1 [0.982-1.04]) nor disease-free survival (P=0.61; HR=0.942 [0.862-1.029]). By univariate analyses, we identified a correlation between overall survival, surgical margins (>1cm) (P=0005; HR=3.4 [1.217-9.919]) and tumour necrosis (P=0.028; HR=0.099 [0.014-0.682]). We did not find any independent prognostic factor by multivariate analysis. CONCLUSION: The prognosis of primary breast sarcoma seems to depend essentially on optimal surgical excision (margin over 1cm). The only potential histological parameter correlated with the prognosis is the presence of tumour necrosis. The histological subtype should not be considered as a prognostic marker for overall or disease-free survival in patients with primary breast sarcoma.


Asunto(s)
Neoplasias de la Mama/epidemiología , Sarcoma/epidemiología , Academias e Institutos , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/terapia , Terapia Combinada , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Hemangiosarcoma/epidemiología , Hemangiosarcoma/terapia , Humanos , Liposarcoma/epidemiología , Liposarcoma/terapia , Mastectomía/métodos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Tumor Filoide/epidemiología , Tumor Filoide/terapia , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Sarcoma/diagnóstico por imagen , Sarcoma/terapia , Sarcoma Mieloide/epidemiología , Sarcoma Mieloide/terapia , Resultado del Tratamiento , Túnez/epidemiología , Adulto Joven
7.
Meat Sci ; 104: 14-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25681560

RESUMEN

This study was conducted to evaluate the effects of dietary pomegranate seed pulp (PSP) on meat color and lipid stability of kids. Thirty-two Mahabadi male kids were randomly assigned to one of four diets with different levels of PSP: 1 - diet without PSP (Control), 2 - diet containing 5% PSP (PSP5), 3 - diet containing 10% PSP (PSP10), and 4 - diet containing 15% PSP (PSP15). The kids were slaughtered at the end of the study and m. longissimus lumborum (LL) was sampled. The TBARS values of both raw and cooked meat were decreased (P<0.0001) by increasing levels of PSP in the diet. The meat of kids fed PSP15 showed higher a* and C* values (P<0.01) and lower H* and b* values (P<0.001), than kids fed with Control diet. The results of this experiment indicated that replacing barley and corn grains with PSP in the diet may improve the color and lipid stability of kid meat.


Asunto(s)
Alimentación Animal , Color , Dieta , Peroxidación de Lípido , Lythraceae , Carne/análisis , Semillas , Animales , Culinaria , Cabras , Hordeum , Humanos , Masculino , Músculo Esquelético , Oxidación-Reducción , Sustancias Reactivas al Ácido Tiobarbitúrico , Zea mays
8.
J Appl Microbiol ; 118(2): 356-67, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25376444

RESUMEN

AIMS: To investigate the effect of culture conditions and medium components on exopolysaccharide (EPS) production by Pseudomonas stutzeri AS22 and to access the EPS performance as a metal-binding exopolysaccharide. METHODS AND RESULTS: The EPS production conditions of Ps. stutzeri AS22 in submerged culture were optimized using two approaches for EPS quantification, and its metal-binding capacity was evaluated using both single and mixed metal ions systems. Maximum EPS level was achieved after 24 h of incubation at 30°C with an initial pH of 8.0, 250 rev min(-1) stirring level and 10% inoculum size. 50 g l(-1) starch, 5 g l(-1) yeast extract, 0.5 g l(-1) NaCl, 1.4 g l(-1) K2 HPO4, 0.4 g l(-1) MgSO4, 0.4 g l(-1) CaCl2 and 1 g l(-1) mannose were found to be the most suitable carbon, nitrogen, mineral and additional carbohydrate sources, respectively. From metal-binding experiments, the crude EPS showed interesting metal adsorption capacity adopting the order Pb >> Co > Fe > Cu >> Cd. Lead was preferentially biosorbed with a maximal uptake of 460 mg g(-1) crude EPS. CONCLUSIONS: Under the optimal culture requirements, EPS level reached 10.2 g l(-1) after 24 h of fermentation, seven times more than the production under initial conditions. According to the metal-binding assay, the crude EPS has potential to be used as a novel biosorbent in the treatment of heavy metals-contaminated water. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results are interesting in terms of yield as well as efficiency for the potential use of the Ps. stutzeri exopolysaccharide as a metal-absorbent polymer in the bioremediation field.


Asunto(s)
Metales Pesados/metabolismo , Polisacáridos Bacterianos/metabolismo , Pseudomonas stutzeri/metabolismo , Carbono/metabolismo , Fermentación , Nitrógeno/metabolismo , Polisacáridos Bacterianos/biosíntesis , Pseudomonas stutzeri/aislamiento & purificación
9.
J Appl Microbiol ; 115(2): 358-66, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23647603

RESUMEN

AIMS: To investigate the distribution of chitinase IO8 in Bacillus cereus strains, the enhancing effects of the chitinase-producing B. cereus strains on biocontrol potential by dual culture assay and in vivo assay against Botrytis cinerea and also the enhancing effects of the chiIO8 on disinfectant properties against seed-borne diseases. Moreover, the application of chiIO8 treatment was also observed to improve the germinative energy. METHODS AND RESULTS: The purification steps included ammonium sulfate precipitation, with columns of DEAE-Sepharose anion-exchange chromatography and Sephacryl S-400 high-resolution gel chromatography. The method gave a 5.8-fold increase in the specific activity and had a yield of 17%. The molecular weight of the partially purified chitinase chiIO8 was found to be around 30 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal pH and optimal temperature of the partially purified chitinase were pH 6.5 and 65°C, respectively. The thermostable chitinase still retained the activity after incubation for 100 min at 65°C, and it was increased about 1.25 times than that of the control (before heating) when the enzyme solution heated at 65°C for 60 min. The partially purified chitinase chiIO8 displays a wide inhibitory spectrum towards all phytopathogenic fungi tested. chiIO8 also exhibited effective disinfectant properties against seed-borne diseases. CONCLUSION: The present investigation emphasizes the potential of chitinase-producing micro-organism as promising biocontrol agents of fungal plant pathogens with chitinous cell wall. The novel chitinase chiIO8 proved an efficient, environmentally safe and user-friendly solution. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first investigation devoted exclusively to analyse the distribution of chitinase in B. cereus. It infers that the chitinase produced by B. cereus might play a role in the activity of the biopesticide.


Asunto(s)
Antifúngicos/farmacología , Bacillus cereus/enzimología , Quitinasas/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/metabolismo , Bacillus cereus/fisiología , Agentes de Control Biológico , Botrytis/efectos de los fármacos , Quitinasas/aislamiento & purificación , Quitinasas/metabolismo , Concentración de Iones de Hidrógeno , Enfermedades de las Plantas/prevención & control , Temperatura
10.
J Appl Microbiol ; 115(2): 424-33, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23663724

RESUMEN

AIMS: Wool, a recalcitrant waste mainly composed of keratin, constituted a serious problem for the environment and was not effectively valorized. This study reported the optimization of wool-waste biodegradation by a new keratinolytic bacterium Bacillus pumilus A1. The in vitro digestibility and the antioxidant potential of wool protein hydrolysate (WPH) were also investigated. METHODS AND RESULTS: The antioxidant potential of WPH was evaluated using in vitro antioxidant assays, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, reducing power and metal (Fe(2+)) chelating activity. Cultivation on 50 g l(-1) of wool for 2 days, at 45°C and at initial pH of 10, resulted in maximum production of amino acids and peptides (39.7 g l(-1)). WPH presented a very high in vitro digestibility (97%) as compared with that of the untreated wool (3%). CONCLUSIONS: The keratin present into the wool-waste was completely solubilized. Interestingly, WPH presented an important DPPH radical-scavenging activity with an IC50 value of 0.14 ± 0.01 mg ml(-1). SIGNIFICANCE AND IMPACT OF STUDY: WPH would be a very useful source of protein and antioxidants in animals' diets.


Asunto(s)
Antioxidantes/metabolismo , Bacillus/metabolismo , Fermentación , Residuos Industriales , Hidrolisados de Proteína/metabolismo , Lana , Animales , Antioxidantes/análisis , Antioxidantes/farmacología , Biodegradación Ambiental , Residuos Industriales/análisis , Queratinas/metabolismo , Hidrolisados de Proteína/análisis , Hidrolisados de Proteína/farmacología , Lana/metabolismo
11.
Perfusion ; 27(4): 300-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22499058

RESUMEN

BACKGROUND: To evaluate the correlation and agreement between central venous saturation (ScvO(2)) and mixed venous saturation (SvO(2)) during cardiopulmonary bypass. METHODS: Twenty-two consecutive patients scheduled for coronary artery surgery were prospectively included. Paired measurements of ScvO(2) and SvO(2) were performed 5 minutes after aortic cross-clamping, after each cardioplegia dose and after de-clamping of the aortic cross-clamp. ScvO(2) and SvO(2) were measured, respectively, by a fibreoptic catheter in the superior vena cava and on blood samples from the venous return line of the extracorporeal circuit, using a blood gas analyser RESULTS: Ninety-five paired measurements of venous saturation were obtained. Correlation between the measurements was associated with an r = 0.55. The mean bias was 2.2 [Limits of agreement: -13.6%, +18%]. Changes in oxygen saturation over time showed an r = 0.4 and a mean bias of 0.2 [Limits of agreement: -17.9%, +18.3%]. Multivariate analysis identified the oxygen consumption index as the only factor explaining this variability. CONCLUSIONS: Although mean biases between the measurements were low, limits of agreement were too large to provide a clinically acceptable estimation of SvO(2) by ScvO(2) in these conditions. Variations in regional oxygen consumption seem to be the main factor worsening the relationship.


Asunto(s)
Puente Cardiopulmonar , Oximetría/métodos , Consumo de Oxígeno , Oxígeno/sangre , Anciano , Soluciones Cardiopléjicas/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Pathol Biol (Paris) ; 60(5): 296-300, 2012 Oct.
Artículo en Francés | MEDLINE | ID: mdl-22041177

RESUMEN

STUDY PURPOSE: Our objective was the study of the development and the maturation of pups whose mothers were subjected to intermittent fasting. MATERIALS AND METHODS: Eight pregnant female Wistar rats were distributed into two groups of four adult females. The rats of the first group were subjected to intermittent fasting beginning on the 14th day of gestation and continued 21 days after parturition. The rats of the second group were normally fed. The young of both groups of rats were sacrificed at the age of 21 days. RESULTS: The pups of the female rats submitted to food restriction showed a reduction of the body weight (-35%), of the thyroid iodine content (P<0.001) and of segment thyroxin (P<0.05). The histological study revealed that these pups presented colloid depletion of this follicular thyroid, non-anastomosing trabeculae, cortical bone thinning, decreased bone mineral content, absence of osteoid formation and decreased number of osteoclasts. CONCLUSION: Dietary restriction imposed on adult rats, from gestation, led to the installation in their pups of a state of malnutrition and a description of thyroid histology. This thyroid abnormality is associated with hypothyroidism that led, at least in part, to the collapse of the ability to regulate bone remodeling.


Asunto(s)
Desarrollo Óseo/fisiología , Privación de Alimentos/fisiología , Efectos Tardíos de la Exposición Prenatal/patología , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Fenómenos Fisiologicos de la Nutrición Prenatal , Glándula Tiroides/patología , Factores de Edad , Animales , Peso Corporal/fisiología , Densidad Ósea , Restricción Calórica/efectos adversos , Recuento de Células , Femenino , Tamaño de los Órganos/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Ratas , Ratas Wistar , Glándula Tiroides/irrigación sanguínea , Glándula Tiroides/ultraestructura
13.
J Dairy Sci ; 94(8): 4075-80, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21787942

RESUMEN

The effects of feeding pomegranate seed pulp (PSP) on milk yield, milk composition, fatty acid profiles of milk fat, and blood metabolites were examined in this study. During a pretrial period, 27 multiparous southern Khorasan (Iran) cross-bred goats were fed a similar diet and dry matter intake, milk yield, and milk composition were recorded. After adaptation and based on pretrial records, the goats were randomly assigned to 1 of 3 experimental diets and were housed in individual stalls. Experimental diets included 0, 6, or 12% of PSP (dry matter basis) and were fed as total mixed rations ad libitum for a 45-d period. Diets were formulated to be isonitrogenous and isocaloric. Supplementation of PSP did not affect dry matter intake or average daily gain of goats. Milk yield was not affected by inclusion of PSP in the diet. Milk fat concentration of goats fed diets with 6 and 12% PSP increased, but milk fat yield, milk protein concentration, and milk solids-not-fat concentration of goats were not affected by diets. Feeding PSP did not affect blood glucose, cholesterol, urea N, triglyceride, or lipoproteins. Feeding goats a diet containing 12% PSP modified the milk fatty acid profile, including conjugated linoleic, punicic, and vaccenic acids.


Asunto(s)
Suplementos Dietéticos , Cabras/fisiología , Ácidos Linoleicos Conjugados/análisis , Ácidos Linolénicos/análisis , Lythraceae , Leche/química , Alimentación Animal , Animales , Ingestión de Alimentos , Femenino , Lactancia , Leche/metabolismo , Semillas
15.
J Dairy Sci ; 89(8): 3087-95, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16840626

RESUMEN

Different mathematical models were evaluated as candidates to describe ruminal dry matter (DM) and crude protein (CP) degradation kinetics of raw and roasted whole soybeans from data obtained using the in situ polyester bag technique. Three models were used: segmented with up to 3 straight lines (model I), negative exponential (model II), and rational function or inverse polynomial (linear over linear; model III). A fourth, a generalized sigmoidal model, was also considered but the data did not exhibit sigmoidicity, so it was dropped from the analysis. Lagged and nonlagged versions of each model were fitted to the DM and CP disappearance curves of 6 different feeds (2 cultivars of raw or differently heat-processed whole soybean). The comparison between lagged and nonlagged versions of each model, based on statistical and behavior characteristics, showed for all models that the discrete lag parameter did not significantly improve the fit to ruminal DM and CP disappearance curves. The comparison between models (using nonlagged equations) showed that models I and II gave better goodness-of-fit than model III. Based on biological characteristics, models II and III underestimated the undegradable DM and CP fractions, but there was no significant difference between models for extent of degradation.


Asunto(s)
Bovinos/metabolismo , Glycine max/metabolismo , Modelos Biológicos , Rumen/metabolismo , Alimentación Animal , Animales , Proteínas en la Dieta/metabolismo , Digestión , Calor , Cinética , Masculino , Matemática
16.
J Ind Microbiol Biotechnol ; 32(5): 186-94, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15843974

RESUMEN

The production and purification of a calcium-dependent protease by Bacillus cereus BG1 were studied. The production of the protease was found to depend specifically on the calcium concentration in the culture medium. This suggests that this metal ion is essential for the induction of protease production and/or stabilisation of the enzyme after synthesis. The calcium requirement is highly specific since other metal ions (such as Mg(2+) and Ba(2+), which both activate the enzyme) are not able to induce protease production. The most appropriate medium for growth and protease production comprises (g L(-1)) starch 5, CaCl(2) 2, yeast extract 2, K(2)HPO(4) 0.2 and KH(2)PO(4) 0.2. The protease of BG1 strain was purified to homogeneity by ultrafiltration, heat treatment, gel filtration on Sephacryl S-200, ion exchange chromatography on DEAE-cellulose and, finally, a second gel filtration on Sephacryl S-200, with a 39-fold increase in specific activity and 23% recovery. The molecular weight was estimated to be 34 kDa on SDS-PAGE. The optimum temperature and pH of the purified enzyme were determined to be 60 degrees C and 8.0, respectively, in 100 mM Tris-HCl buffer + 2 mM CaCl(2).


Asunto(s)
Bacillus cereus/enzimología , Calcio/metabolismo , Péptido Hidrolasas/aislamiento & purificación , Péptido Hidrolasas/metabolismo , Bacillus cereus/crecimiento & desarrollo , Carbono/metabolismo , Medios de Cultivo/química , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Microbiología Industrial/métodos , Nitrógeno/metabolismo , Péptido Hidrolasas/química , Temperatura
17.
Environ Technol ; 24(10): 1261-8, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14669806

RESUMEN

An activated sludge reactor, operated at room temperature (20-30 degrees C) was used to treat saline wastewaters generated by marine-products industries. The system was operated continuously and the influence of the organic loading rates (OLRs), varying from 250 to 1000 mg COD l(-1) day(-1), on chemical oxygen demand (COD) removal was investigated. The system, inoculated with NaCl-acclimated culture, removed up to 98% and 88% of the influent COD concentrations at OLRs of 250 and 1000 mg COD L(-1) day(-1), respectively. Since the organic pollution is essentially composed of proteins, microorganisms, which produced proteolytic enzymes, were isolated from the activated sludge culture. One bacterium with the highest protease activity, identified as Bacillus cereus, was chosen for protease production in fishery wastewaters of different concentrations containing combined heads and viscera powder. Protease synthesis was strongly enhanced when cells were cultivated in two times diluted fishery wastewaters. The enhancement of protease synthesis could have been due to the presence in effluent of organic matters or salts, which stimulated the growth of the strain and protease production.


Asunto(s)
Reactores Biológicos , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Animales , Bacillus cereus/fisiología , Endopeptidasas/biosíntesis , Explotaciones Pesqueras , Industria de Alimentos , Residuos Industriales , Compuestos Orgánicos/metabolismo , Aguas del Alcantarillado , Cloruro de Sodio , Temperatura , Contaminación del Agua/prevención & control
18.
Environ Technol ; 24(1): 59-67, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12641253

RESUMEN

Full scale composting studies were performed with stoned (SEOOPSW) and non stoned exhausted olive-oil processing solid waste (NSEOOPSW) mixed with 20% poultry manure to reach a C/N ratio of around 30 and to improve the chemical and microbiological properties of the end products. The experiment was performed on two windrows (3 m wide, 2.5 m high and 10 tonne weight) to investigate the effects of stone removal and poultry manure addition on composting process efficiency and on the quality of composts. The partially stone removal operation reduced the total composting time by at least one month compared with the untreated waste. The addition of poultry manure improved the chemical quality of the end product, as shown by the doubling of the nitrogen concentration after four months composting together with the increased amount of P and K. Compost from stoned exhausted olive-oil processing solid waste had higher levels of cation exchange capacity (CEC) and humic acid content with a lower [FA/HA] ratio indicating a high polymerisation level. Agronomic field test showed that both composts are not phytotoxic. When applied at the rate of 40 tonne ha(-1) to a potato culture, they produced approximately the same yield (46 and 48.5 tonne ha(-1)) but they acted differently in terms of plant development. Compost produced from the NSEOOPSW acted more positively on the stem length (84.1 against 77.6 cm) and on leaf weight (354 against 238 g), whereas compost from the SEOOPSW more positively affected tuber sizes (76% large grade compared to 55%).


Asunto(s)
Conservación de los Recursos Naturales , Estiércol , Aceites de Plantas/metabolismo , Eliminación de Residuos/métodos , Agricultura , Animales , Fenómenos Geológicos , Geología , Sustancias Húmicas , Aceite de Oliva , Fósforo/análisis , Plantas , Potasio/análisis , Suelo , Pruebas de Toxicidad
19.
Bioresour Technol ; 80(1): 49-51, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11554601

RESUMEN

Fish flours from Sardinelle (Sardinella aurita) were prepared and tested for protease production by Bacillus subtilis. Protease synthesis was strongly induced when cells were grown in media containing only a combined head and viscera preparation. Sardinelle heads and viscera flour enhanced protease production up to 100% more than commercial peptones. The enhancement could have been due to a high lipid content, which might have contained nutritional factors acting as inducers, since defatting fish meal led to a decrease in protease production.


Asunto(s)
Bacillus subtilis/enzimología , Endopeptidasas/biosíntesis , Productos Pesqueros/microbiología , Bacillus subtilis/crecimiento & desarrollo , Hidrólisis
20.
Arch Inst Pasteur Tunis ; 76(1-4): 27-31, 1999.
Artículo en Francés | MEDLINE | ID: mdl-14666755

RESUMEN

Production of lipase by Staphylococcus sp. in media containing fish peptones from sardinelle (Sardinella aurita) prepared in the laboratory was studied. Lipase production is strongly affected by lipids present in fish flours. Fish peptones prepared from dIgresed whole flesh was an excellent substrate for lipase production. A comparison of lipase production in media containing fish peptones or high quality commercial peptones indicated that fish peptones enhanced enzyme formation.


Asunto(s)
Técnicas Bacteriológicas/métodos , Medios de Cultivo Condicionados/normas , Harina de Pescado/análisis , Lipasa/biosíntesis , Peptonas/química , Staphylococcus/enzimología , Animales , Técnicas Bacteriológicas/normas , Humanos , Hidrólisis , Lipasa/análisis
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