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•Pre-treatments modified the structure and composition of Agave durangensis leaves.•Pre-treated Agave durangensis leaves have better enzymatic digestibility.•Ultrasound pre-treatment ...increases the production of hydrolytic enzymes.
Approximately 1 million tons of agave plants are processed annually by the Mexican tequila and mezcal industry, generating vast amounts of agroindustrial solid waste. This type of lignocellulosic biomass is considered to be agroindustrial residue, which can be used to produce enzymes, giving it added value. However, the structure of lignocellulosic biomass makes it highly recalcitrant, and results in relatively low yield when used in its native form. The aim of this study was to investigate an effective pre-treatment method for the production of commercially important hydrolytic enzymes. In this work, the physical and chemical modification of Agave durangensis leaves was analysed using ultrasound and high temperature as pre-treatments, and production of enzymes was evaluated. The pre-treatments resulted in modification of the lignocellulosic structure and composition; the ultrasound pre-treatment improved the production of inulinase by 4 U/mg and cellulase by 0.297 U/mg, and thermal pre-treatment improved β-fructofuranosidase by 30 U/mg.
The impact of nonlinear effects in the diffractive observables that will be measured in future electron-ion collisions is investigated. We present, for the first time, the predictions for the ...diffractive structure function and reduced cross sections derived using the solution to the Balitsky–Kovchegov equation with the collinearly-improved kernel and including the impact-parameter dependence. We demonstrate that the contribution of the diffractive events is enhanced in nuclear collisions and that the study of the ratio between the nuclear and proton predictions will be useful to discriminate among different models of the dipole-target scattering amplitude and, consequently, will allow us to constrain the description of QCD dynamics in parton densities.
Aim
As options to treat recalcitrant bacterial infections which are increasingly limited due to multidrug‐resistant strains, searching for new, effective antibacterial compounds is necessary. One ...strategy is to generate treatment alternatives by drug repurposing.
Methods and Results
In this work, phenotypic microarrays were used for the screening of miscellaneous compounds against the growth and biofilm formation of Acinetobacter baumannii, an important emergent multidrug‐resistant opportunistic pathogen. The results showed that the phenothiazine derivatives, such as promethazine, trifluoperazine, thioridazine, and chlorpromazine, inhibited the growth of antibiotic‐sensitive and multidrug‐resistant strains (showing minimal inhibitory concentrations ranging from 0·05 to 0·6 g l−1 and minimal bactericidal concentrations ranging from 0·1 to 2·5 g l−1). All phenothiazine derivatives were active against biofilm cells (with minimal biofilm eradication concentrations ranging from 0·5 to >3 g l−1). Chlorpromazine promoted reactive oxigen species (ROS) production, and cell membrane and DNA damage. Chlorpromazine showed synergy with antibiotics such as ceftazidime, meropenem, and colistin and was an effective treatment for experimentally infected Galleria mellonella when combined with ceftazidime.
Conclusions
It was demonstrated that phenothiazine derivatives, especially chlorpromazine, are drugs with attractive antibacterial properties against nosocomial MDR strains of A. baumannii, by generating ROS and cell membrane and DNA damage.
Significance and Impact of the Study
The present study indicates that repurposing phenothiazine derivatives for treating recalcitrant infections by A. baumannii could be promising.
We have developed a model in which the quantum fluctuations of the proton structure are characterised by hot spots, whose number grows with decreasing Bjorken-x. Our model reproduces the F2(x,Q2) ...data from HERA at the relevant scale, as well as the exclusive and dissociative J/ψ photoproduction data from H1 and ALICE. Our model predicts that for Wγp≈500 GeV, the dissociative J/ψ cross section reaches a maximum and then decreases steeply with energy, which is in qualitatively good agreement to a recent observation that the dissociative J/ψ background in the exclusive J/ψ sample measured in photoproduction by ALICE decreases as energy increases. Our prediction provides a clear signature for gluon saturation at LHC energies.
The study of intestinal microbiota in vector insects like triatomines is paramount in parasitology because many parasitic species inhabit the vector's gut. Although knowledge on the gut microbiota in ...various vectors of the parasitic flagellate Trypanosoma cruzi has grown, research efforts have focused on South American triatomines. This study reports the isolation of bacterial microbiota in the anterior and posterior gut of Meccus pallidipennis (a triatomine species endemic to Mexico) by culture, as well as its identification by phenotypic and biochemical tests and its quantification by counting colony‐forming units. The study was performed on fifth‐instar nymph and adult specimens of M. pallidipennis, either laboratory‐bred or collected in the field and either infected or not with T. cruzi. Overall, 17 bacterial species were identified, with the genera Bacillus and Staphylococcus being the most prevalent regardless of the origin of the insects. No differences were observed in the number of bacterial species in the gut of laboratory‐bred and field‐collected insects, neither with respect to life stage or infection status. In general, the Shannon‐Weaver diversity index was higher in non‐infected insects than in infected ones. Further studies using non‐culture methods are required to determine whether bacterial species diversity is modified by laboratory breeding.
Microbiota of Meccus pallidipennis showed no changes depending on life stage, infection status and origin.
Firmicutes and Proteobacteria were the dominant bacterial groups, similar to that reported for other triatomines.
Staphylococcus and Bacillus were the dominant bacterial genera in both laboratory‐bred triatomines and those collected in the field.
The coherent photonuclear production of a J/ψ vector meson at the LHC has been computed using two different sets of solutions of the impact-parameter dependent Balitsky-Kovchegov equation. The ...nuclear dipole scattering amplitudes are obtained either from (i) solutions for this process off proton targets coupled with a Glauber-Gribov prescription, or (ii) from solutions obtained with an initial condition representing the nucleus. These approaches predict different cross sections, which are compared with existing data from ultra-peripheral collisions at the LHC. The latter approach seems to better describe current measurements. Future LHC data should be precise enough to select one of the two approaches as the correct one.
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