Based on colony spreading, chitosan from shrimp waste in agar media inhibited the growth of
Aspergillus niger by 47.26%; there were not differences (
P
>
0.05) with respect to commercial chitosan ...(Fluka, BioChemika) (56.16%). All chitosan films showed similar glass transition temperatures (
P
>
0.05) with respect to cellophane control; however, chemically, all chitosan films showed an increase in the
T
g values that could be related with the decrease (
P
≤
0.05) in elongation percentage with respect to the control film. According to FT-IR spectroscopic analysis of chitosan films, the fungistatic activity can be related to the hydrogen bonds’ formation between the amino groups of chitosan with the hydroxyl groups from polymer or sorbitol. The plasticizer addition increased (
P
≤
0.05) the elongation of chitosan films. The Young's module,
E, was lower (
P
≤
0.05) for all chitosan films comparing with cellophane. When incorporated into the composite films elaborated by casting, chitosan retained its fungistatic activity. Even though the activity against fungi growth was lower (15.66% for non-plasticized silage chitosan films, pC
S), a reduction (
P
≤
0.05) in the hyphae diameter of
A. niger was observed. Results suggest that it is feasible to elaborate antifungal chitosan films, with good thermal stability and acceptable mechanical properties for food packaging.
Display omitted
•Pecan nutshell could be used as carbon source for production of BC by G. entanii.•Cellulose produced by G. entanii had high purity.•BC production by G. entanii using pecan nutshell ...is the first report.•Data obtained can be useful for the synthesis of methylcellulose from other BC.
Pecan nutshell is an abundant waste with a high content of carbohydrates. According to its chemical composition, pecan nutshell could be used as carbon source for Gluconacetobacter entanii, a bacterium that produces cellulose with high purity and nanometric characteristics. Bacterial cellulose (BC) was obtained from a static culture medium using pecan nutshell as carbon source and saccharose as control. Results showed that the pecan nutshell could be used as carbon source for production of BC. The cellulose yield ranged around 2.816 ± 0.040 g/L for 28 days. The morphological, structural and chemical properties of the cellulose produced were similar to those reported for others BC. The spectroscopic characterization indicated the chemical functionalization of BC and the reduction of its crystallinity. The production of BC with G. entanii using pecan nutshell as carbon source, is the first report. The BC could have potential use in chemical functionalization and in the preparation of biocomposites.
Food technologists are always looking to improve the functional properties of proteins. In this sense, in last years ultrasound has been used to improve some functional properties. For this reason, ...and considering that jumbo squid is an important fishery in northwest Mexico, the purpose of this research was to determine the effect of pulsed ultrasound on the physicochemical characteristics and emulsifying properties of squid (Dosidicus gigas) mantle proteins. Pulsed ultrasound (20kHz, 20, and 40% amplitude) was applied for 30, 60, and 90s to a protein extract prepared from giant squid mantle causing an increase (p<0.05) in surface hydrophobicity (So) from 108.4±1.4 to 239.1±2.4 after application of pulsed ultrasound at 40% of amplitude for 90s. The electrophoretic profile and the total and reactive sulfhydryl contents were not affected (p⩾0.05) by the ultrasound treatment. The emulsifying ability of the protein solution was improved (p<0.05), whereas the Emulsifier Activity Index (EAI) varied from123.67±5.52m2/g for the control and increased up to 217.7±3.8m2/g after application of the ultrasound. The Stability Emulsifier Index (EEI) was improved at 40% of amplitude by 60 and 90s. The results suggested that pulsed ultrasound used as pretreatment induced conformational changes in giant squid proteins, which improved the interfacial association between protein-oil phases, thus contributing to the improvement of their emulsifient properties.
Psoriasis is a common inflammatory skin disease with a prevalence of 2-3% in individuals of European ancestry. In a genome-wide search for copy number variants (CNV) using a sample pooling approach, ...we have identified a deletion comprising LCE3B and LCE3C, members of the late cornified envelope (LCE) gene cluster. The absence of LCE3B and LCE3C (LCE3C_LCE3B-del) is significantly associated (P = 1.38E-08) with risk of psoriasis in 2,831 samples from Spain, The Netherlands, Italy and the United States, and in a family-based study (P = 5.4E-04). LCE3C_LCE3B-del is tagged by rs4112788 (r 2 = 0.93), which is also strongly associated with psoriasis (P < 6.6E-09). LCE3C_LCE3B-del shows epistatic effects with the HLA-Cw6 allele on the development of psoriasis in Dutch samples and multiplicative effects in the other samples. LCE expression can be induced in normal epidermis by skin barrier disruption and is strongly expressed in psoriatic lesions, suggesting that compromised skin barrier function has a role in psoriasis susceptibility.
Biologically active compounds with different modes of action, such as, antiproliferative, antioxidant, antimicrotubule, have been isolated from marine sources, specifically algae and cyanobacteria. ...Recently research has been focused on peptides from marine animal sources, since they have been found as secondary metabolites from sponges, ascidians, tunicates, and mollusks. The structural characteristics of these peptides include various unusual amino acid residues which may be responsible for their bioactivity. Moreover, protein hydrolysates formed by the enzymatic digestion of aquatic and marine by-products are an important source of bioactive peptides. Purified peptides from these sources have been shown to have antioxidant activity and cytotoxic effect on several human cancer cell lines such as HeLa, AGS, and DLD-1. These characteristics imply that the use of peptides from marine sources has potential for the prevention and treatment of cancer, and that they might also be useful as molecular models in anticancer drug research. This review focuses on the latest studies and critical research in this field, and evidences the immense potential of marine animals as bioactive peptide sources.
The reduced lifespan of cryopreserved spermatozoa in the mare reproductive tract has been attributed to both capacitative and apoptotic changes. However, there is a lack of studies investigating both ...phenomena simultaneously. In order to improve our knowledge in this particular point, we studied in raw and frozen-thawed samples apoptotic and capacitative markers using a wide battery of test based in flow cytometry. Apoptotic markers evaluated were caspase 3 activity, externalization of phosphatidylserine (PS), and mitochondrial membrane potential. Markers of changes resembling capacitation were membrane fluidity, tyrosine phosphorylation, and intracellular sodium. Conventional and computational flow cytometry using nonlinear dimensionally reduction techniques (t-distributed stochastic neighbor embedding (t-SNE)) and automatic classification of cellular expression by nonlinear stochastic embedding (ACCENSE) were used. Most of the changes induced by cryopreservation were apoptotic, with increase in caspase 3 activation (P < 0.01), PS translocation to the outer membrane (P < 0.001), loss of mitochondrial membrane potential (P < 0.05), and increase in intracellular Na+ (P < 0.01). Average values of markers of capacitative changes were not affected by cryopreservation; however, the analysis of the phenotype of individual spermatozoa using computational flow cytometry revealed the presence of subpopulations of spermatozoa experiencing capacitative changes. For the first time advanced computational techniques were applied to the analysis of spermatozoa, and these techniques were able to disclose relevant information of the ejaculate that remained hidden using conventional flow cytometry.
The study of perioperative drug reactions remains a major challenge for both diagnosis and therapy. The lack of a standard assessment of allergy to general anesthetics and of data establishing the ...true value of skin tests for most drugs used in induction and maintenance of anesthesia, as well as the lack of commercially available reagents for in vitro tests, renders the study of these reactions problematic. The aims of this study were to provide a diagnostic protocol for drug challenge testing with general anesthetics, to establish an etiological diagnosis that is as specific as possible, and to determine the predictive value of skin tests.
Twenty-nine patients with perioperative drug reactions were included in the study from November 2008 to December 2018.
We confirmed the high negative predictive value of the tests (96%-100%) in the case of propofol, rocuronium, and fentanyl. To our knowledge, this is the first study to describe drug challenge testing with general anesthetics and, therefore, to establish the true negative predictive value of skin tests, which leads to a definitive diagnosis and safer surgery.
After assessing risks and benefits and considering the importance of this group of drugs, we conclude that drug challenge testing with general anesthetics is necessary. We propose a protocol for perioperative drug reactions that enables us to make a highly accurate etiological diagnosis with minimum risk for the patient.
PDF
