Search results for " biotechnology"
showing 10 items of 3723 documents
Glucosamine measurement as indirect method for biomass estimation of Cunninghamella elegans grown in solide state cultivation conditions
2001
Glucosamine measurement has been tested as the indirect method to estimate the biomass produced by Cunninghamella elegans during solid state cultivation (SSC). The independence of this cell constituent content from the age and the conditions of the culture have been verified. The influence of the medium composition, in particular the nature of the carbon source on glucosamine amount is presented. Glucosamine can be considered as a well-adapted biomass indicator, with the necessity to establish for each medium tested a prior correlation between biomass and glucosamine amount. This correlation should be defined in submerged conditions before applying the biomass estimating method in SSC.
Nitrogen removal from on-site treated anaerobic effluents using intermittently aerated moving bed biofilm reactors at low temperatures
2005
Abstract On-site post-treatment of anaerobically pre-treated dairy parlour wastewater (DPWW e ; 10 °C) and mixture of kitchen waste and black water (BWKW e ; 20 °C) was studied in moving bed biofilm reactors (MBBR). The focus was on removal of nitrogen and of residual chemical oxygen demand (COD). Moreover, the effect of intermittent aeration and continuous vs. sequencing batch operation was studied. All MBBRs removed 50–60% of nitrogen and 40–70% of total COD (COD t ). Complete nitrification was achieved, but denitrification was restricted by lack of carbon. Nitrogen removal was achieved in a single reactor by applying intermittent aeration. Continuous and sequencing batch operation provid…
Bioconversion of amino acids into flavouring alcohols and esters by Erwinia carotovora subsp. atroseptica
1991
International audience; Erwinia carotovora subsp. atroseptica produced flavour compounds when infecting endives (Cichorium intybus). These compounds were identified as esters and branched-chain alcohols.They were produced from amino acids and some of them such as methionol, methionol acetate, isobutanol, isobutyl acetate, beta-phenyl ethanol and tryptophol were produced with good yields.
Anhydrobiosis in yeasts: Psychrotolerant yeasts are highly resistant to dehydration.
2018
Yeast cells are able to transition into a state of anhydrobiosis (temporary reversible suspension of metabolism) under conditions of desiccation. One of the most efficient approaches for understanding the mechanisms underlying resistance to dehydration-rehydration is to identify yeasts, which are stable under such treatments, and compare them with moderately resistant species and strains. In the current study, we investigated the resistance to dehydration-rehydration of six psychrotolerant yeast strains belonging to two species. All studied strains of Solicoccozyma terricola and Naganishia albida were found to be highly resistant to dehydration-rehydration. The viability of S. terricola str…
Activated Carbon from Renewable Sources: Thermochemical Conversion and Activation of Biomass and Carbon Residues from Biomass Gasification
2017
Activated carbon is one of the most widely applied adsorbent. As a porous carbon, it is used for the purification of both gaseous and liquid emissions. Activated carbon is prepared from fossil resources, such as coal, or from biomass through (hydro)thermal processing followed by chemical and/or physical activation. Further, some biomass thermal treatment processes, such as biomass gasification, produce carbon residues that can be modified to activated carbon with physical or chemical activation methods. The desired properties of activated carbon, i.e. high specific surface area and porosity, high carbon content and excellent sorption capacity, can be modified and optimized during thermochem…
Pulsed electric field assisted extraction of nutritionally valuable compounds from microalgae Nannochloropsis spp. using the binary mixture of organi…
2015
Abstract This work studies the potential of the pulsed electric field (PEF) assisted extraction of nutritionally valuable compounds from microalgae Nannochloropsis spp. using the binary mixture of organic solvents (dimethyl sulfoxide, DMSO and ethanol, EtOH) and water. The one-stage (E I ) and two stage (E II ) extraction procedures were compared. The procedure E I included the common extraction using the binary mixtures. Two stage (E II ) extraction procedure involved PEF-treatment (20 kV/cm) of microalgae suspension (1% wt.) and extraction in water as the first step. The second step included the common extraction using the binary mixtures. The effects of extraction procedure and concentra…
Positive effect of platelet rich fibrin on osseointegration
2016
Background Leukocyte-platelet rich fibrin (L-PRF) is a second generation platelet concentrate clinically used to accelerate tissue healing and bone regeneration. Achieving reduced implant osseointegration time could provide immediate or early loading of implants. The aim of this study was to evaluate the L-PRF-induced osseointegration and bone-implant contact (BIC) in an experimental animal model. Material and Methods Twelve 4-month-old New Zealand white rabbits were used. Following general anesthesia, 3-5 mL of blood was obtained from the central artery in rabbit ear and L-PRF was prepared. Two implant cavities (5 mm long and 3 mm in diameter) were created in each tibia with a total of fou…
Combined influence of bud load and bud position along the cane on vegetative and reproductive parameters of grape cv. Grillo
2019
Cultivar Grillo vines are characterized by problems with flower biology (the fertility of basal buds) and fructification (millerandage). In this study, to manage the variability in bunch weight with winter pruning and to program others canopy management practices (i.e. early defoliation), three different treatments of bud load were set up by leaving the cane with 3, 6 or 10 buds. The effects of bud load and cane length were studies regarding bud fertility, shoot leaf area, and the number of flowers and berries, as well as the relationship between leaf area and percentage of fruit set, leaf area/flower and percentage of fruit set, and the number of hens and chicks berries. Shoots in the dist…
Stimulation of Defense Reactions in Medicago truncatula by Antagonistic Lipopeptides from Paenibacillus sp. Strain B2
2010
ABSTRACT With the aim of obtaining new strategies to control plant diseases, we investigated the ability of antagonistic lipopolypeptides (paenimyxin) from Paenibacillus sp. strain B2 to elicit hydrogen peroxide (H 2 O 2 ) production and several defense-related genes in the model legume Medicago truncatula . For this purpose, M. truncatula cell suspensions were used and a pathosystem between M. truncatula and Fusarium acuminatum was established. In M. truncatula cell cultures, the induction of H 2 O 2 reached a maximum 20 min after elicitation with paenimyxin, whereas concentrations higher than 20 μM inhibited H 2 O 2 induction and this was correlated with a lethal effect. In plant roots in…
Influence of shear rate and concentration ratio on viscous synergism. Application to xanthan—Iocust bean gum— NaCMC mixtures Influencia de la velocid…
2000
A method is described that allows the development of an empirical approach to quantify synergistic interactions and their variations with shear rate. The approach is based on the definition of a viscous synergism index, Iv. The method is applied to xanthan-locust bean gum gels, and an equation is developed for relating the synergism index to shear rate, γ, and the locust bean gum/xanthan gum concentration ratio, z. The value of at which that function has a maximum, IMV, is calculated. This value of z provided an estimation of the proportion of gums at which maximum synergism occurs. A decreasing exponential dependence of these IMV on γ is shown. The influence of the addition of a fixed pro…