Essential oils of clove (
Syzygium aromaticum L.), fennel (
Foeniculum vulgare Miller), cypress (
Cupressus sempervirens L.), lavender (
Lavandula angustifolia), thyme (
Thymus vulgaris L.), ...herb-of-the-cross (
Verbena officinalis L.), pine (
Pinus sylvestris) and rosemary (
Rosmarinus officinalis) were tested for their antimicrobial activity on 18 genera of bacteria, which included some important food pathogen and spoilage bacteria. Clove essential oil showed the highest inhibitory effect, followed by rosemary and lavender. In an attempt to evaluate the usefulness of these essential oils as food preservatives, they were also tested on an extract made of fish, where clove and thyme essential oils were the most effective. Then, gelatin–chitosan-based edible films incorporated with clove essential oil were elaborated and their antimicrobial activity tested against six selected microorganisms:
Pseudomonas fluorescens,
Shewanella putrefaciens,
Photobacterium phosphoreum,
Listeria innocua,
Escherichia coli and
Lactobacillus acidophilus. The clove-containing films inhibited all these microorganisms irrespectively of the film matrix or type of microorganism. In a further experiment, when the complex gelatin–chitosan film incorporating clove essential oil was applied to fish during chilled storage, the growth of microorganisms was drastically reduced in gram-negative bacteria, especially enterobacteria, while lactic acid bacteria remained practically constant for much of the storage period. The effect on the microorganisms during this period was in accordance with biochemical indexes of quality, indicating the viability of these films for fish preservation.
The rising interest in the valorisation of industrial by-products is one of the main reasons why exploring different species and optimizing the extracting conditions of collagen and gelatin has ...attracted the attention of researchers in the last decade. The most abundant sources of gelatin are pig skin, bovine hide and, pork and cattle bones, however, the industrial use of collagen or gelatin obtained from non-mammalian species is growing in importance. The classical food, photographic, cosmetic and pharmaceutical application of gelatin is based mainly on its gel-forming properties. Recently, and especially in the food industry, an increasing number of new applications have been found for gelatin in products such as emulsifiers, foaming agents, colloid stabilizers, biodegradable film-forming materials and micro-encapsulating agents, in line with the growing trend to replace synthetic agents with more natural ones. In the last decade, a large number of studies have dealt with the enzymatic hydrolysis of collagen or gelatin for the production of bioactive peptides. Besides exploring diverse types of bioactivities, of an antimicrobial, antioxidant or antihypertensive nature, studies have also focused on the effect of oral intake in both animal and human models, revealing the excellent absorption and metabolism of Hyp-containing peptides. The present work is a compilation of recent information on collagen and gelatin extraction from new sources, as well as new processing conditions and potential novel or improved applications, many of which are largely based on induced cross-linking, blending with other biopolymers or enzymatic hydrolysis.
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Most films used to preserve foodstuffs are made from synthetic plastic materials. However, for environmental reasons, attention has recently turned to biodegradable films. Gelatin has been ...extensively studied for its film-forming capacity and applicability as an outer covering to protect food against drying, light, and oxygen. Moreover, it is one of the first materials proposed as a carrier of bioactive components. Gelatins from alternatives to mammalian species are gaining prominence, especially gelatins from marine fish species. Because of their good film-forming abilities, fish gelatins may be a good alternative to synthetic plastics for making films to preserve foodstuffs. The mechanical and barrier properties of these films depend largely on the physical and chemical characteristics of the gelatin, especially the amino acid composition, which is highly species specific, and the molecular weight distribution, which depends mainly on processing conditions. Different film formulations can be developed to extend the films' physical and chemical properties and to add new functional attributes. This paper reviews the most recent scientific literature dealing with films based on gelatins from different fish species and considers various strategies intended to improve the physical properties of such films by combining fish gelatins with such other biopolymers as soy protein isolate, oils and fatty acids, and certain polysaccharides. The use of plasticizers and cross-linking agents is also discussed. Specific attributes, such as antimicrobial and antioxidant activities, may be also conferred by blending the gelatin with chitosan, lysozyme, essential oils, plant extracts, or vitamin C to produce an active packaging biomaterial.
We present Gran Telescopio CANARIAS CanariCam 8.7 μm imaging and 7.5–13 μm spectroscopy of six local systems known to host an active galactic nucleus (AGN) and have nuclear star formation. Our main ...goal is to investigate whether the molecules responsible for the 11.3 μm polycyclic aromatic hydrocarbon (PAH) feature are destroyed in the close vicinity of an AGN. We detect 11.3 μm PAH feature emission in the nuclear regions of the galaxies as well as extended PAH emission over a few hundred parsecs. The equivalent width (EW) of the feature shows a minimum at the nucleus but increases with increasing radial distances, reaching typical star-forming values a few hundred parsecs away from the nucleus. The reduced nuclear EWs are interpreted as due to increased dilution from the AGN continuum rather than destruction of the PAH molecules. We conclude that at least those molecules responsible for the 11.3 μm PAH feature survive in the nuclear environments as close as 10 pc from the AGN and for Seyfert-like AGN luminosities. We propose that material in the dusty tori, nuclear gas discs, and/or host galaxies of AGN is likely to provide the column densities necessary to protect the PAH molecules from the AGN radiation field.
This multicenter phase I trial was designed to evaluate the safety and efficacy of bortezomib (Bz) as part of both the conditioning regimen and the graft-versus-host disease (GvHD) prophylaxis. ...Patients received fludarabine, melphalan and Bz (days -9 and -2). GVHD prophylaxis consisted of Bz (days +1, +4, and +7), sirolimus (Siro) from day -5 and tacrolimus (Tk) from -3 (except the first five patients that did not receive Tk). Twenty-five patients with poor prognostic multiple myeloma were included. Eleven out of the 19 patients had high-risk features. Out of the 21 patients evaluable at day +100, 14 were in CR (67%) and 7 (33%) in PR. Cumulative incidence (CI) of nonrelapse mortality at 1 year was 24%. CI of grades 2-4 and 3-4 acute GvHD was 35% and 10%, respectively; CI of chronic GvHD was 35% and 55% at 1 and 2 years, respectively. Overall and event free survival at 2 years were 64% and 31%, respectively. Bz as part of the conditioning regimen and in the combination with Siro/tacrolimus for GvHD prophylaxis is safe and effective allowing an optimal disease control early after transplant and reducing the risk of GvHD.
In order to provide gelatin films with antioxidant capacity, two sulphur-free water-insoluble lignin powders (L1000 and L2400) were blended with a commercial fish-skin gelatin from warm water species ...at a rate of 85% gelatin: 15% lignin (w/w) (G–L1000 and G–L2400), using a mixture of glycerol and sorbitol as plasticizers. The water soluble fractions of G–L1000 and G–L2400 films were 39.38 ± 1.73% and 46.52 ± 1.66% respectively, rendering radical scavenging capacity (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, ABTS assay)) of 27.82 ± 2.19 and 15.31 ± 0.88 mg vitamin C equivalents/g film, and ferric ion reducing ability (FRAP assay) of 258.97 ± 8.83 and 180.20 ± 5.71 μmol Fe2+ equivalents/g film, respectively. Dynamic oscillatory test on film-forming solutions and Attenuated Total Reflectance (ATR)-FTIR spectroscopy study on films revealed strong lignin-induced protein conformational changes, producing a noticeable plasticizing effect on composite films, as deduced from the study of mechanical (traction and puncture tests) and thermal properties (Differential Scanning Calorimetry, DSC). The gelatin films lose their typical transparent and colourless appearance by blending with lignin; however, the resulting composite films gained in light barrier properties, which could be of interest in certain food applications for preventing ultraviolet-induced lipid oxidation. Lignin proved to be an efficient antioxidant at non-cytotoxic concentrations, however, no remarkable antimicrobial capacity was found.
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A commercial low-gelling fish skin gelatin was used to prepare edible films by casting with glycerol and sorbitol added as plasticizers. In order to improve the extremely low water resistance of ...gelatin films, composite films were prepared with increasing concentrations (wt/wt) of lignosulphonate (LS) from eucalyptus wood (100:0, 85:15, 80:20, 75:25, 70:30 and 65:35, gelatin:LS). How gelatin film properties were affected by the different types of gelatin and LS was determined by comparing bovine gelatin and three different LS (Ca
2+, Mg
2+ and Na
+) in a mixture ratio of 80:20. Physical properties of films were characterized in terms of tensile strength, elongation at break, water solubility, water vapour permeability and opacity. Dynamic oscillatory tests of film-forming solutions revealed strong LS interference with the cold-renaturation ability of gelatin. LS ratios equal to or higher than the 80:20 blend interfered with intermolecular aggregation of gelatin helices. Supposedly, LS acted as a filler, inducing mostly nonbonding interactions with gelatin, as deduced from Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR) and Differential Scanning Calorimetry (DSC) studies. Lignosulphonate significantly reduced the elongation at break of fish gelatin films, water solubility being drastically reduced with a mixture ratio of 80:20 or higher. The water solubility of bovine gelatin–LS composite films was significantly lower than that for fish gelatin, regardless of the type of LS employed. For potential food packaging applications, the three LS were characterized in terms of cytotoxicity, radical scavenging capacity (DPPH assay) and antimicrobial capacity. The effective antioxidant levels (IC
50: 83.4–97.5 μg/mL) were noticeably lower than the cytotoxic ones (IC
50: 1480–1745 μg/mL), indicating that these compounds could be used as antioxidants at non-cytotoxic concentrations. No relationship between antioxidant and antimicrobial properties could be observed, the only notable antimicrobial finding being some activity against yeasts.
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► A novel fish gelatin–lignosulphonate film, not previously reported. ► Improvement of water resistance of extremely high soluble fish gelatin films. ► Comparisons between fish gelatin and bovine gelatin. ► Lignosulphonate as potential candidate to be used in food packaging.
Considerable research has documented that exposure to traumatic events has negative effects on physical and mental health. Much less research has examined the predictors of traumatic event exposure. ...Increased understanding of risk factors for exposure to traumatic events could be of considerable value in targeting preventive interventions and anticipating service needs.
General population surveys in 24 countries with a combined sample of 68 894 adult respondents across six continents assessed exposure to 29 traumatic event types. Differences in prevalence were examined with cross-tabulations. Exploratory factor analysis was conducted to determine whether traumatic event types clustered into interpretable factors. Survival analysis was carried out to examine associations of sociodemographic characteristics and prior traumatic events with subsequent exposure.
Over 70% of respondents reported a traumatic event; 30.5% were exposed to four or more. Five types - witnessing death or serious injury, the unexpected death of a loved one, being mugged, being in a life-threatening automobile accident, and experiencing a life-threatening illness or injury - accounted for over half of all exposures. Exposure varied by country, sociodemographics and history of prior traumatic events. Being married was the most consistent protective factor. Exposure to interpersonal violence had the strongest associations with subsequent traumatic events.
Given the near ubiquity of exposure, limited resources may best be dedicated to those that are more likely to be further exposed such as victims of interpersonal violence. Identifying mechanisms that account for the associations of prior interpersonal violence with subsequent trauma is critical to develop interventions to prevent revictimization.
Salmon muscle is considerably affected by cooking with the resulting loss of its appealing red colour. The combined use of high pressure with fish gelatin–lignin film is proposed as an alternative to ...the more aggressive thermal processing procedures, with the aim of improving the appearance and overall quality of salmon fillets in ready-to-eat or semi-prepared dishes. The effects of high pressure processing (300
MPa, 10
min, 5
°C or 40
°C) and conventional heating (90
°C, 10
min) were evaluated in terms of colour changes, protein denaturation, as well as protein and lipid oxidation, by comparison with raw muscle. The stability of the processed products was assessed by monitoring changes in microbial growth and total volatile basic nitrogen and thiobarbituric acid reactive substances during 23
days of chilled storage. Fourier transform infrared spectroscopy (FTIR), apparent viscosity and dynamic oscillatory studies revealed notable differences in the overall degree and nature of protein aggregation between high pressure and heating treatments, especially when performed at 5
°C instead of 40
°C. SDS–PAGE of the protein fraction solubilised in 0.8
M NaCl showed MHC and α-actinin to be the main myofibrillar proteins denatured by high pressure processing at 40
°C, while actin was more denatured when pressurised at 5
°C. The film attenuated colour changes associated with high pressure treatment, especially at 5
°C, where redness was more preserved without jeopardising the appearance of a ready-to-eat product. High pressure processing at 5
°C in combination with gelatin–lignin film was found to improve protein quality of salmon fillets. The film reduced the levels of carbonyl groups formed immediately after processing, and prevented lipid oxidation from taking place at advanced stages of chilled storage. However, the effect on microbial growth was negligible, since total counts were similar for muscle with or without the film.
A functional concentrate rich in proteins and lipids was obtained from an industrial shrimp cooking juice by using a centrifugal separator, and it was characterized in terms of chemical composition ...parameters and functional or biological activity (antioxidant and ACE-inhibitory capacities). The concentrate presented 116 g/kg protein, 135 g/kg crude fat and ash content less than 10 g/kg, with predominance of Na ions, followed by K, Ca, Mg, Cu, Fe, Zn and Mn. A relative abundance of glucose, glycerol, polyalcohols, acetate and phosphate was found. The antioxidant (as determined by ABTS, FRAP, chelating and photoluminescence assays) and ACE-inhibitory capacities of the material recovered from the shrimp cooking juice were strongly related to the presence of small peptides (1355–502 Da), with a clear predominance of Gly, Pro, Glu, Asp and Arg. Other antioxidants, such as free astaxanthin (cis and trans isomers) and derived esters, were also detected.
•Material from shrimp cooking juice with antioxidant and ACE-inhibitory capacities.•Compositional properties of a functional concentrate were reported.•Peptides rich in Gly and Pro were responsible for high ACE-inhibitory capacity.•Free astaxanthin and derived esters were detectable in the cooking juice.
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