Search results for "Bios"
showing 10 items of 2557 documents
The impact of the cultivation practices on arbuscular mycorrhizal symbiosis mechanism in a walnut tree - corn agroforestry system
2021
The English walnut (Juglans regia L.) is the main species cultivated for the production of edible nuts. Owing to a sparse canopy and a deep rooting system, walnut is an ideal species for alley cropping, an agroforestry practice able to enhance productivity through interplant facilitative mechanisms. Walnut agroforestry requires the large scale production of seedling rootstocks selected to provide the best anchorage, vigour, and tolerance of pathogens. Due to the heterozygosity of walnut, the characteristics of agronomical interest of the chosen cultivar are not inherited via seed propagation. In vitro plant tissue culture thus plays a key role in mass propagation of high-quality walnut root…
Desiccation by Exposure to Space Vacuum or Extremely Dry Deserts: Effect on Microorganisms
2003
General Limits of Growth at Low Water Activities Dormant Life Molecular Events Induced by Desiccation Survival at Extremely Low Water Activity Survival Under Extremely Dry Desert Conditions Keywords: anhydrobiosis; desiccation; extreme environments; freeze-drying; panspermia thesis; space: survival in space; space vacuum; water activity
Recent progress in optical and electrochemical biosensors for sensing of Clostridium botulinum neurotoxin
2018
Abstract Botulinum toxin is a neurotoxic protein which produced from Clostridium botulinum and related species and it block acetylcholine release from presynaptic nerve terminals at the neuromuscular junctions. This toxin is life threatening for millions of people and growing menace to society since causing human botulism. Enzymatic activity of Botulinum neurotoxin within the cell made it hazardous and lead to flaccid paralysis. However, there isn't any reliable and precise remedy for this toxin. Therefore, there is an urgent need for early detection of this toxin in a fast and meticulous way with a robust and cost-effective relationship for real-time monitoring of Botulinum neurotoxin. Sev…
Induction of stress proteins inLeuconostoc oenos to perform direct inoculation of wine
1994
The enhancement or induction of the protein synthesis was clearly observed in cells ofL. oenos labeled with35S for five proteins during heat shock at 42°C and acid shock at pH 3. Furthermore, no stress protein was induced after exposure ofL. oenos to ethanol shock 10% (v/v). Moreover, survival ofL. oenos in wine and ability to perform alolactic fermentation was improved after direct inoculation when cells were pretreated at 42°C.
NAD(P)H regeneration is the key for heterolactic fermentation of hexoses in Oenococcus oeni
2002
Oenococcus oeni (formerly Leuconostoc oenos) can perform malolactic fermentation, converting L-malate to L-lactate and carbon dioxide, in wines. The energy and redox potential required to support the growth of the micro-organism are supplied mainly by the consumption of carbohydrates via the heterolactic pathway. In the first steps of hexose metabolism two molecules of NAD(P)(+) are consumed, which must be regenerated in later reactions. The aim of this work was to test if aerobic growth of O. oeni promotes higher cell yields than anaerobic conditions, as has been shown for other lactic acid bacteria. O. oeni M42 was found to grow poorly under aerobic conditions with glucose as the only car…
Immigrant Labour and viticulture activity: the Case of the Ribera del Duero
2017
Spain is one of the main countries with significant presence in the global wine market. Ribera de Duero is a region which currently has a very important presence both nationally and internationally in the global production of wine. Studies conducted in the area have addressed different angles of those changes. One of the aspects more addressed in existing studies is the wine tourism strategy, the elements that have enabled the growth of this strategy and the impacts on the region. However, one of the aspects that has not been very much discussed is the importance of the labor force involved in this activity. On this communication, we will focus on analyzing the importance of the migrant la…
Electrical conductivity as a state indicator for the start-up period of anaerobic fixed-bed reactors.
2016
The aim of this work was to analyse the applicability of electrical conductivity sensors for on-line monitoring the start-up period of an anaerobic fixed-bed reactor. The evolution of bicarbonate concentration and methane production rate was analysed. Strong linear relationships between electrical conductivity and both bicarbonate concentration and methane production rate were observed. On-line estimations of the studied parameters were carried out in a new start-up period by applying simple linear regression models, which resulted in a good concordance between both observed and predicted values. Electrical conductivity sensors were therefore identified as an interesting method for monitori…
Fe(III)-DOTA/Fe(III)-NOTA Complexes: Attractive Alternative Markers for Future Electrochemical Biosensors
2020
Metallic complexes of macrocycles chelators 1,4,7-triazacyclononane-N,N,N-triacetic acid (NOTA) and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) were synthetized with iron (III) giving Fe(III)-DOTA and Fe(III)-NOTA complexes. They were studied in comparison of ferricyanide and ferrocenemethanol on cyclic voltammetry with glassy carbon working electrode (GC) and screen-printed carbon electrode (SPCE). Diffusion coefficients and heterogeneous electron transfer rate constants were determined with Randles-Sevcik and Nicholson-Lavagnini methods. Using SPCE. The average values of diffusion coefficient and transfer rate constant were respectively of 1.34 × 10−6 cm2 s−1 and 1.01 …
Xanthine oxidase catalyzes the oxidation of retinol.
2007
In mammals, xanthine oxidase (E.C. 1.17.3.2) catalyzes the hydroxylation of a wide variety of heterocyclic substrates such as purines, pyrimidines, and pterins, in addition to aldehydes [1] as all-trans-retinaldehyde [2-5]. Here, we show that buttermilk xanthine oxidase was capable to oxidizing all-trans-retinol (t-ROL) to all-trans-retinaldehyde (t-RAL) that was successively oxidized to all-trans-retinoic acid (t-RA). A rise in the enzyme activity, when t-ROL-CRBP complex was assayed, with respect to the free t-ROL, was observed. Furthermore, treatment of the enzyme with Na2S and glutathione resulted in a significant increment in catalytic activity toward t-ROL and t-RAL, due to the recons…
Biosorption of nickel (II) and zinc (II) from aqueous solutions by the biomass of yeast Yarrowia lipolytica
2017
Abstract This study examined the biosorption process of Ni(II) and Zn(II) from an aqueous solution by dead biomass of Yarrowia lipolytica. Optimum biosorption conditions were determined as a function of pH, biomass dosage, contact time, and temperature. The biosorbent was characterized by FTIR, which indicated the participation of hydroxyl, carboxyl, amide and amine groups in the process of binding the metal ions. The results showed that the biosorption processes of both metal ions closely followed pseudo-second order kinetics. The equilibrium data of Ni(II) and Zn(II) ions at 20, 30 and 40°C fitted the Langmuir and Freundlich isotherm models. Langmuir isotherm provided a better fit to the …