Properties and Biodegradability of Films Based on Cellulose and Cellulose Nanocrystals from Corn Cob in Mixture with Chitosan.

The increase in consumer demand for more sustainable packaging materials represents an opportunity for biopolymers utilization as an alternative to reduce the environmental impact of plastics. Cellulose (C) and chitosan (CH) are attractive biopolymers for film production due to their high abundance, biodegradability and low toxicity. The objective of this work was to incorporate cellulose nanocrystals (NC) and C extracted from corn cobs in films added with chitosan and to evaluate their properties and biodegradability. The physicochemical (water vapor barrier, moisture content, water solubility and color) and mechanical properties of the films were evaluated. Component interactions using Fourier-transform infrared (FTIR) spectroscopy, surface topography by means of atomic force microscopy (AFM), biodegradability utilizing a fungal mixture and compostability by burying film discs in compost were also determined. The C-NC-CH compared to C-CH films presented a lower moisture content (17.19 ± 1.11% and 20.07 ± 1.01%; w/w, respectively) and water vapor permeability (g m−1 s−1 Pa−1 × 10−12: 1.05 ± 0.15 and 1.57 ± 0.10; w/w, respectively) associated with the NC addition. Significantly high roughness (Rq = 4.90 ± 0.98 nm) was observed in films added to NC, suggesting a decreased homogeneity. The biodegradability test showed larger fungal growth on C-CH films than on CH films (>60% and <10%, respectively) due to the antifungal properties of CH. C extracted from corn cobs resulted in a good option as an alternative packaging material, while the use of NC improved the luminosity and water barrier properties of C-CH films, promoting strong interactions due to hydrogen bonds.

Physical, Structural, Barrier, and Antifungal Characterization of Chitosan-Zein Edible Films with Added Essential Oils.

Edible films (EFs) have gained great interest due to their ability to keep foods safe, maintaining their physical and organoleptic properties for a longer time. The aim of this work was to develop EFs based on a chitosan-zein mixture with three different essential oils (EOs) added: anise, orange, and cinnamon, and to characterize them to establish the relationship between their structural and physical properties. The addition of an EO into an EF significantly affected (p < 0.05) the a* (redness/greenness) and b* (yellowness/blueness) values of the film surface. The EFs presented a refractive index between 1.35 and 1.55, and thus are classified as transparent. The physical properties of EFs with an added EO were improved, and films that incorporated the anise EO showed significantly lower water vapor permeability (1.2 ± 0.1 g mm h-1 m-2 kPa-1) and high hardness (104.3 ± 3.22 MPa). EFs with an added EO were able to inhibit the growth of Penicillium sp. and Rhizopus sp. to a larger extent than without an EO. Films' structural changes were the result of chemical interactions among amino acid side chains from zein, glucosamine from chitosan, and cinnamaldehyde, anethole, or limonene from the EOs as detected by a Raman analysis. The incorporation of an EO in the EFs' formulation could represent an alternative use as coatings to enhance the shelf life of food products.

Physicochemical and Antimicrobial Characterization of Beeswax-Starch Food-Grade Nanoemulsions Incorporating Natural Antimicrobials.

Nanoemulsions are feasible delivery systems of lipophilic compounds, showing potential as edible coatings with enhanced functional properties. The aim of this work was to study the effect of emulsifier type (stearic acid (SA), Tween 80 (T80) or Tween 80/Span 60 (T80/S60)) and emulsification process (homogenization, ultrasound or microfluidization) on nanoemulsion formation based on oxidized corn starch, beeswax (BW) and natural antimicrobials (lauric arginate and natamycin). The response variables were physicochemical properties, rheological behavior, wettability and antimicrobial activity of BW-starch nanoemulsions (BW-SN). The BW-SN emulsified using T80 and microfluidized showed the lowest droplet size (77.6 ± 6.2 nm), a polydispersion index of 0.4 ± 0.0 and whiteness index (WI) of 31.8 ± 0.8. This BW-SN exhibited a more negative ζ-potential: -36 ± 4 mV, and Newtonian flow behavior, indicating great stability. BW-SN antimicrobial activity was not affected by microfluidization nor the presence of T80, showing inhibition of the deteriorative fungi R. stolonifer, C. gloeosporioides and B. cinerea, and the pathogenic bacterium S. Saintpaul. In addition, regardless of emulsifier type and emulsification process, BW-SN applied on the tomato surface exhibited low contact angles (38.5° to 48.6°), resulting in efficient wettability (-7.0 mN/m to -8.9 mN/m). These nanoemulsions may be useful to produce edible coatings to preserve fresh-produce quality and safety.

Electrostatic Fermentation: Molecular Response Insights for Tailored Beer Production.

Electrostatic fermentation avoids the cellular redox imbalance of traditional fermentation, but knowledge gaps exist. This study explores the impact of electrostatic fermentation on the growth, volatile profile, and genetic response of Saccharomyces pastorianus Saflager S-23. The applied voltage (15 and 30 V) in the electrostatic fermentation system increased the growth and substrate utilization of S. pastorianus while decreasing ethanol production. The aromas typically associated with traditional fermentation, such as alcoholic, grape, apple, and sweet notes, were diminished, while aromas like roses, fruits, flowers, and bananas were augmented in electrostatic fermentation. RNA-seq analysis revealed upregulation of genes involved in cell wall structure, oxidoreductase activity, and iron ion binding, while genes associated with protein synthesis, growth control, homeostasis, and membrane function were downregulated under the influence of applied voltage. The electrostatic fermentation system modulates genetic responses and metabolic pathways in yeast, rendering it a promising method for tailored beer production. Demonstrating feasibility under industrial-scale and realistic conditions is crucial for advancing towards commercialization.

PVA-Based Electrospun Biomembranes with Hydrolyzed Collagen and Ethanolic Extract of Hypericum perforatum for Potential Use as Wound Dressing: Fabrication and Characterization.

Biological, physicochemical, structural, and thermal properties of PVA-based electrospun wound dressings added with hydrolyzed collagen (HC) and different concentrations of Hypericum perforatum ethanolic extract (EEHP) were studied. Membrane characterization was carried out by X-ray diffraction, Fourier infrared spectroscopy, differential scanning calorimetry, barrier properties, scanning electron microscopy, image analysis (diameter and pore size), as well as antimicrobial and anti-inflammatory activities. Results showed that the PVA/HC/EEHP materials, fabricated under controlled conditions of temperature and humidity, generated fiber membranes with diameters between 140−390 nm, adequate porosity and pore size for cell growth (67−90% and 4−16 µm, respectively), and good barrier properties (0.005−0.032 g·m−2 s−1) to be used in the treatment of conditions on the skin, and was even better than some commercial products. Finally, they showed to have anti-inflammatory (>80%), and antimicrobial activity against S. aureus and S. epiderm. Furthermore, higher crystalline structure was observed according to the EEHP concentration. In addition, this is the first report in which PVA/HC/EEHP membranes are successfully fabricated and characterized.

Rheological and Antimicrobial Properties of Chitosan and Quinoa Protein Filmogenic Suspensions with Thyme and Rosemary Essential Oils.

Food packaging faces the negative impact of synthetic materials on the environment, and edible coatings offer one alternative from filmogenic suspensions (FS). In this work, an active edible FS based on chitosan (C) and quinoa protein (QP) cross-linked with transglutaminase was produced. Thyme (T) and rosemary (R) essential oils (EOs) were incorporated as antimicrobial agents. Particle size, Z potential, and rheological parameters were evaluated. The antimicrobial activity against Micrococcus luteus (NCIB 8166) and Salmonella sp. (Lignieres 1900) was monitored using atomic force microscopy and image analysis. Results indicate that EOs incorporation into C:QP suspensions did not affect the Z potential, ranging from -46.69 ± 3.19 mV to -46.21 ± 3.83 mV. However, the polydispersity index increased from 0.51 ± 0.07 to 0.80 ± 0.04 in suspensions with EO. The minimum inhibitory concentration of active suspensions against Salmonella sp. was 0.5% (v/v) for thyme and 1% (v/v) for rosemary. Entropy and fractal dimension of the images were used to confirm the antimicrobial effect of EOs, which modified the surface roughness.

Improved Thermal and Reusability Properties of Xylanase by Genipin Cross-Linking to Magnetic Chitosan Particles.

Enzymes are gradually increasingly preferred over chemical processes, but commercial enzyme applications remain limited due to their low stability and low product recovery, so the application of an immobilization technique is required for repeated use. The aims of this work were to produce stable enzyme complexes of cross-linked xylanase on magnetic chitosan, to describe some characteristics of these complexes, and to evaluate the thermal stability of the immobilized enzyme and its reusability. A xylanase was cross-linked to magnetite particles prepared by in situ co-precipitation of iron salts in a chitosan template. The effect of temperature, pH, kinetic parameters, and reusability on free and immobilized xylanase was evaluated. Magnetization, morphology, size, structural change, and thermal behavior of immobilized enzyme were described. 1.0 ± 0.1 µg of xylanase was immobilized per milligram of superparamagnetic chitosan nanoparticles via covalent bonds formed with genipin. Immobilized xylanase showed thermal, pH, and catalytic velocity improvement compared to the free enzyme and can be reused three times. Heterogeneous aggregates of 254 nm were obtained after enzyme immobilization. The immobilization protocol used in this work was successful in retaining enzyme thermal stability and could be important in using natural compounds such as Fe3O4@Chitosan@Xylanase in the harsh temperature condition of relevant industries.

Genetic variability in CYP3A4 and CYP3A5 in primary liver, gastric and colorectal cancer patients.

BACKGROUND: Drug-metabolizing enzymes play a role in chemical carcinogenesis through enzymatic activation of procarcinogens to biologically reactive metabolites. The role of gene polymorphisms of several cytochrome P450 enzymes in digestive cancer risk has been extensively investigated. However, the drug-metabolizing enzymes with the broader substrate specificity, CYP3A4 and CYP3A5, have not been analyzed so far. This study aims to examine associations between common CYP3A4 and CYP3A5 polymorphisms and digestive cancer risk. METHODS: CYP3A4 and CYP3A5 genotypes were determined in 574 individuals including 178 patients with primary liver cancer, 82 patients with gastric cancer, 151 patients with colorectal cancer, and 163 healthy individuals. RESULTS: The variant allele frequencies for patients with liver cancer, gastric cancer, colorectal cancer and healthy controls, respectively, were: CYP3A4*1B, 4.8 % (95% C.I. 2.6-7.0), 3.7 % (0.8-6.6) 4.3% (2.0-6.6) and 4.3% (2.1-6.5); CYP3A5*3, 91.8 % (93.0-97.4), 95.7% (92.6-98.8), 91.7% (88.6-94.8) and 90.8% (87.7-93.9). The association between CYP3A4*1B and CYP3A5*3 variant alleles did not significantly differ among patients and controls. No differences in genotypes, allele frequencies, or association between variant alleles were observed with regard to gender, age at diagnosis, tumour site or stage. CONCLUSION: Common polymorphisms on CYP3A4 and CYP3A5 genes do not modify the risk of developing digestive cancers in Western Europe.

Conservation of the mycelia of the medicinal mushroom Humphreya coffeata (Berk.) Stey. in sterile distilled water.

Currently, there is a growing interest in obtaining and studying the biologically active compounds from higher basidiomycetes, such as Ganoderma lucidum, Lentinus edodes and Inonotus obliquus[1], but the techniques for safe long-term storage are time-consuming, susceptible to contamination, and do not prevent genetic and physiological changes during long-term maintenance [2]. A recent strategy for obtaining biologically active compounds is using mycelia submerged cultures of these mushrooms, cultured under controlled laboratory conditions [1]. However, obtaining spores of these fungi under these conditions is difficult, and in most cases the way to obtain the spores is unknown [1]. Therefore, the strategy for mycelium storage seems to be more appropriated and simple.•A modification of Castellani's method [3-7] is proposed for higher basidiomycetes, by using the mycelium of Humphreya coffeata (Berk.) Stey., whose culture filtrates demonstrated bioactivity against lymphoma cells [8].•H. coffeata (Berk.) Stey. was grown on malt extract agar with filter paper disks that were removed after 4 days, placed in tubes with sterile distilled water, and stored at 4 °C.•Filter paper disks with H. coffeata (Berk.) Stey. stored at 4 °C were confirmed to be viable for up to 18 months, with no visible morphological alterations.

Antipsychotics and seizures: higher risk with atypicals?

PURPOSE: Almost all antipsychotics have been associated with a risk of epileptic seizure provocation. Among the first-generation antipsychotics (FGA) chlorpromazine appears to be associated with the greatest risk of seizures among the second-generation antipsychotics (SGA) clozapine is thought to be most likely to cause convulsions. This information is largely based on studies that are not sufficiently controlled. Besides, information about the seizure risk associated with newer antipsychotics is scarce. METHOD: The Pharmacovigilance Unit of the Basque Country (network of centers of the Spanish Pharmacovigilance System, SEFV) provided reporting data for adverse reactions (AR) from the whole SEFV to estimate the reporting odds ratio (ROR) for antipsychotics and seizures ("convulsions" as Single MedDra Query). Data was obtained from SEFV database from 1984 to the June 2011. RESULTS: The total number of convulsions reported for SGA was 169 (total reported AR 3.204). The number of convulsions reported for FGA was 35 (total reported AR 2.051). 94 convulsions were reported in association with clozapine (total AR 1.052). The ROR for SGA versus FGA was 3.2 (CI 95%: 2.21-4.63). The ROR for SGA excluding clozapine versus FGA was 2.08 (CI 95%: 1.39-3.12). CONCLUSION: Our results show that SGA may pose a higher risk of seizures than FGA, mainly, but not only due to clozapine. This is line with recent studies suggesting that some SGA carried a higher average risk of electroencephalographic abnormalities than many FGA. Nonetheless, It is well known that spontaneous reports do not allow strong inferences about adverse drug effects, because differences in reporting fractions by time, drug or type of event are difficult or even impossible to distinguish from differences in the occurrence rates of adverse events. Still, we consider that the possibility of SGA carrying a higher risk of seizure induction than FGA warrants further research.

Levofloxacin-induced delirium in a patient suffering from schizoaffective disorder and multiple sclerosis.

Levofloxacin induced psychiatric adverse effects are rare, although they can be serious. There are just five cases of fluoroquinolone-induced delirium published in the medical literature. To our best knowledge, none of them occurred in psychotic patients. We report a case of a 38-year-old Caucasian man diagnosed with schizoaffective disorder and multiple sclerosis who developed delirium and visual hallucinations after initiating levofloxacin therapy. In psychiatric patients, suspecting levofloxacin could be responsible for the symptoms can be a diagnostic challenge, since they could be interpreted like worsening of the mental state as well. Although levofloxacin-induced delirium is a rare adverse event, physicians should be aware of the occurrence of this serious, but potentially reversible CNS complication of levofloxacin, even in psychotic patients.

Levofloxacin-Induced Delirium in a Patient Suffering from Schizoaffective Disorder and Multiple Sclerosis.

Levofloxacin induced psychiatric adverse effects are rare, although they can be serious. There are just five cases of fluoroquinolone-induced delirium published in the medical literature. To our best knowledge, none of them occurred in psychotic patients. We report a case of a 38-year-old Caucasian man diagnosed with schizoaffective disorder and multiple sclerosis who developed delirium and visual hallucinations after initiating levofloxacin therapy. In psychiatric patients, suspecting levofloxacin could be responsible for the symptoms can be a diagnostic challenge, since they could be interpreted like worsening of the mental state as well. Although levofloxacin-induced delirium is a rare adverse event, physicians should be aware of the occurrence of this serious, but potentially reversible CNS complication of levofloxacin, even in psychotic patients.