Procalcitonin biomarker kinetics fails to predict treatment response in perioperative abdominal infection with septic shock

International audienceIntroduction: Procalcitonin (PCT) biomarker is suggested to tailor antibiotic therapy in the medical intensive care unit (ICU) but studies in perioperative medicine are scarce. The aim of this study was to determine whether PCT reported thresholds are associated with the initial treatment response in perioperative septic shock secondary to intra-abdominal infection. Methods: This single ICU, observational study included patients with perioperative septic shocks secondary to intra-abdominal infection. Demographics, PCT at days 0, 1, 3, 5, treatment response and outcome were collected. Treatment failure included death related to the initial infection, second source control treatment or a new onset intra-abdominal infection. The primary endpoint was to assess whether PCT thresholds (0.5 ng/ml or a drop from the peak of at least 80%) predict the initial treatment response. Results: We included 101 consecutive cases. Initial treatment failed in 36 patients with a subsequent mortality of 75%. Upon admission, PCT was doubled when treatment ultimately failed (21.7 ng/ml +/- 38.7 vs. 41.7 ng/ml +/- 75.7; P = 0.04). Although 95% of the patients in whom PCT dropped down below 0.5 ng/ml responded to treatment, 50% of the patients in whom PCT remained above 0.5 ng/ml also responded successfully to treatment. Moreover, despite a PCT drop of at least 80%, 40% of patients had treatment failure. Conclusions: In perioperative intra-abdominal infections with shock, PCT decrease to 0.5 ng/ml lacked sensitivity to predict treatment response and its decrease of at least 80% from its peak failed to accurately predict treatment response. Studies in perioperative severe infections are needed before using PCT to tailor antibiotic use in this population

Gélatines de poisson : Préparation, propriétés et applications [Fish gelatins : Preparation, properties and applications]

Foods and pharmaceutical industries all over the world attend an increasing demand for gelatin, a biopolymer derived from collagen. Gelatins are widely used due to their biocompatibility, biodegradation, physical and functional properties. Porcine and bovine gelatins, the most commonly used, are subject to major constraints and skepticism among consumers, this is due to socio-cultural and health-related issues. Therefore, there is an increasing demand for alternative sources. The by-products generated by fish-processing industries are a potential source for the production of gelatins. Fish gelatin possesses interesting characteristics and may thus be considered as an alternative to mammalian gelatin for use in food, pharmaceutical and photographic products. This review enumerates gelatin preparation processes, as well as, their physical properties, and their potential applications in many fields, such as food, pharmacy and photography industries

Effect of ultrasound pretreatment and Maillard reaction on structure and antioxidant properties of ultrafiltrated smooth-hound viscera proteins-sucrose conjugates

The effect of ultrasound (US) pre-treatment on the evolution of Maillard reaction (MR), induced between low molecular weight (LMW) peptides and sucrose, was studied. LMW peptides (<1 kDa) were obtained by the ultrafiltration of smooth hound viscera protein hydrolysates, produced by Neutrase, Esperase and Purafect. MR was induced by heating the LMW peptides in the presence of sucrose for 2 h at 90 °C, without or with US pre-treatment. During the reaction, a marked decrease in pH values, coupled to the increase in colour of the Maillard reaction products (MRPs), were recorded. In addition, after sonication, the glycation degree was significantly enhanced in Esperase-derived peptides/sucrose conjugates (p < 0.05). Moreover, results showed that thermal heating, particularly after US treatment, reduced the bitter taste and enhanced the antioxidant capacities of the resulting conjugates. Hence, it could be concluded that US leads to efficient mixing of sugar-protein solution and efficient heat/mass transfer, contributing to increase the MR rate.This work was funded by the Ministry of Higher Education and Scientific Research, Tunisia. Emerging Research Group Grant from Generalitat Valenciana in Spain (GV/2015/138) and JAEDOC-CSIC postdoctoral contract of L.M. cofounded by the European Social Found are acknowledged.Peer reviewe

Peptidomic analysis of bioactive peptides in zebra blenny (Salaria basilisca) muscle protein hydrolysate exhibiting antimicrobial activity obtained by fermentation with Bacillus mojavensis A21

The present study investigates the antibacterial activity of zebra blenny (Salaria basilisca) protein hydrolysates obtained by fermentation with a proteolytic bacterium, Bacillus mojavensis A21. The fermentative zebra blenny protein hydrolysate (FZPH), with a degree of hydrolysis (DH) of 17.35%, was fractionated by size exclusion chromatography on a Sephadex G-25 into six major fractions (F1-F6). Fraction F2, which exhibited antibacterial activity against several Gram-positive and Gram-negative bacteria, was further fractionated by reversed-phase high performance liquid chromatography (RP-HPLC). Fractions A and B from RP-HPLC exhibiting the highest antibacterial activity, were analysed using nano ESI-LC–MS/MS to identify the sequences of the peptides. A total of 28 and 41 peptides, containing from 8 to 31 amino acid residues, were identified in sub-fractions A and B, respectively. Further, identified bioactive peptides sharing sequences with previously identified peptides were reported. The results of this study suggest that FZPH is a good source of natural antimicrobial peptides and therefore, they could serve as a beneficial ingredient for nutraceuticals.This work was funded by the Ministry of Higher Education and Scientific Research-Tunisia. Grant AGL2014-57367-R from MINECO (Spain) and FEDER funds and JAEDOC-CSIC postdoctoral contract of L.M. cofounded by the European Social Found are acknowledged.Peer reviewe

Wound healing activity of cuttlefish gelatin gels and films enriched by henna (Lawsonia inermis) extract

The in vivo wound-healing potential of gels and films based on cuttlefish skin gelatin (CSG) incorporated with aqueous henna extract (AHE) (at 50 and 500 μg/ml) was studied. As wound healing is related to reactive oxygen species (ROS), this study was first conducted to evaluate the antioxidant activity of AHE by DPPH radical-scavenging, β-carotene-linoleate bleaching, and reducing power assays. The major volatile compounds of AHE were lawsone, dimethyl sulfoxide, dimethyl sulfide, eugenol and maltol. The finding of the study showed that the incorporation of AHE into gelatin gels and films enhanced the antioxidant activity in a dose-dependent manner. In the wound-healing study, topical application of gelatin hydrogels or films enriched by AHE, on the wound site in a rat model, enhanced significantly wound healing activity and helped to prevent from inflammation damage, when compared to the control and CICAFLORA®-treated groups. Further, all preparations were found to improve the antioxidant status of treated rats as was evidenced by increased antioxidant enzymatic activities and reduced malondialdehyde (MDA) content. The increase in the activities of catalase (CAT), superoxide dismutase (SOD) and gluthatione peroxydase (GPx) in wound tissues revealed that some bioactive compounds in AHE are able to enhance the healing of wounds by reducing the damage caused by ROS. Wound-healing activity was confirmed by histopathology studies. The obtained results showed that the addition of AHE to the gelatin matrix could improve the wound healing activity.This work was funded by the Ministry of Higher Education and Scientific Research, Tunisia. Emerging Research Group Grant from Generalitat Valenciana in Spain (GV/2015/138) and JAEDOC-CSIC postdoctoral contract of L.M. cofounded by the European Social Found are acknowledged.Peer reviewe

Rheological and structural properties of Hemiramphus far skin gelatin: Potential use as an active fish coating agent

The present study aims to characterize black-barred (Hemiramphus far) skin gelatin (BG) gel enriched or not with its hydrolysate (BGH) in terms of their rheological and micro-structural properties, as well as to evaluate their effect on smooth hound fillet quality during chilled storage. The results of the rheological properties showed that peptides addition influenced elastic and loss modulus as observed from temperature sweep. Based on the microstructure, BG gel had a fine network with small voids that were filled by the presence of BGH peptides. On the other hand, when used as coating agents for smooth hound fillets, BG and BG-BGH showed that, in comparison to control group, fish spoilage was significantly delayed in coated samples. In fact, after 8 days of storage, samples coated with BG and BG+BGH showed the lowest weight loss levels, and preserved their initial water activity (a) values. In addition, fillet coating was able to significantly reduce TVB-N content and oxidation process, as reflected by the low malondialdehyde and carbonyl contents. Furthermore, compared to the control group, all the treatments were found to reduce the degree of microbial deterioration of the fillets, leading to low the free amino acids and nucleotides contents in wrapped fish samples. Therefore, gelatin coating helps to prevent fish fillets from deterioration and oxidation processes.This work was funded and financially supported by the Ministry of Higher Education and Scientific Research, Tunisia (Grant no. 18PJEC06-03)

Characterization and Potential Use of Cuttlefish Skin Gelatin Hydrolysates Prepared by Different Microbial Proteases

Composition, functional properties, and in vitro antioxidant activities of gelatin hydrolysates prepared from cuttlefish skin were investigated. Cuttlefish skin gelatin hydrolysates (CSGHs) were obtained by treatment with crude enzyme preparations from Bacillus licheniformis NH1, Bacillus mojavensis A21, Bacillus subtilis A26, and commercial alcalase. All CSGHs had high protein contents, 74.3–78.3%, and showed excellent solubility (over 90%). CSGH obtained by alcalase demonstrated high antioxidant activities monitored by β-carotene bleaching, DPPH radical scavenging, lipid peroxidation inhibition, and reducing power activity. Its antioxidant activity remained stable or increased in a wide range of pH (1–9), during heating treatment (100°C for 240 min) and after gastrointestinal digestion simulation. In addition, alcalase-CSGH was incorporated into turkey meat sausage to determine its effect on lipid oxidation during 35 days of storage period. At 0.5 mg/g, alcalase-CSGH delayed lipid oxidation monitored by TBARS and conjugated diene up to 10 days compared to vitamin C. The results reveal that CSGHs could be used as food additives possessing both antioxidant activity and functional properties

Design of Gelatin Pouches for the Preservation of Flaxseed Oil during Storage

International audienceFlaxseed oil (FO) is composed mainly of polyunsaturated fatty acids that are very sensitive to oxidation induced by oxygen, temperature, and light. To overcome this problem, gelatin-based films containing glucose are crosslinked via the Maillard reaction (MR) at 120 °C and used for the conception of pouches in which the FO was packaged. The prepared pouches, as well as the oil alone, are incubated at 50 °C for 21 days. The results show that the peroxide index of the oil stored in the gelatin-based pouches is almost stable and decreases on the 21st day. The specific extinction coefficients prove a more pronounced degradation of the non-package oil (control). In addition, the results of thiobarbituric acid reactive substances (TBARs) test reveal higher values in the control, with a tendency to continuously increase up until the 21st day. However, the oil stored in the pouches reveals less TBARs content, decreasing with oxidation time. The non-heated glucose-supplemented pouches showed the best results, suggesting a moderate and gradual development of the MR at 50 °C. The application of pouches based on gelatin films seems to be an effective and interesting tool for protecting FO against lipid oxidation, acting as perfectly biodegradable and sustainable containers for small doses

Bioactive films based on cuttlefish (Sepia officinalis) skin gelatin incorporated with cuttlefish protein hydrolysates: Physicochemical characterization and antioxidant properties

International audienceThe objective of this study was to apply cuttlefish (Sepia officinalis) skin protein isolate (CSPI) and hydrolysates (CSPH), using commercial Savinase® and Purafect® enzymes, as bioactive additives in the elaboration of gelatin-based films. CSPH and CSPI enriched films were colored and exhibited a higher UV-barrier properties compared to gelatin film. In addition, compared to CSPI added film, an increase of the glass transition temperature by 20 % and 4 %, respectively, for Purafect and Savinase hydrolysates enriched films was noted. However, elongation at break decreased significantly for CSPH incorporated films by 2.5-fold. The tensile strength was reduced by 28.2 % and 44.4 % for Purafect and Savinase hydrolysates added films, respectively. Furthermore, a decrease of water contact angle by 45 % and 51 % for films added with Purafect and Savinase hydrolysates, respectively, was displayed compared to gelatin film. Interestingly, CSPH enriched films also displayed higher antioxidant potential than control gelatin films evaluated by several in vitro assays

Composite bioactive films based on smooth-hound viscera proteins and gelatin: Physicochemical characterization and antioxidant properties

International audienceThe bioconversion of fish by-products through the development of biodegradable films offers the possibility to their valorization and, on the other side, to decrease the use of synthetic packaging, responsible for several ecological problems due to their non-biodegradability. Thus, in the present study, blend films (Bl-F) and bilayer films (Bi-F) based on commercial bovine gelatin (CBG) and smooth-hound viscera proteins, incorporated or not with sulfated polysaccharides (SP) or smooth-hound peptides (SHP) with molecular weight below 1 kDa, were successfully made using the casting method. Results of the scanning electron microscopy micrographs showed that the two biopolymers were compatible. Moreover, the mechanical properties analyses revealed that films based on the smooth-hound viscera proteins possessed higher tensile strength (TS) but lower elongation at break (EAB), compared to the gelatin film, where Bl-F were mechanically stronger and less deformable than Bi-F. Based on the differential scanning calorimetry analyses, Bl-F have the highest glass transition temperature (Tg) (63–67 °C), confirming their glassy character at room conditions. In addition, Bl-F were found more effective on preventing moisture transfer, in a 30–84% relative humidity differential, than Bi-F, though the SHP addition slightly reduced the water vapor barrier efficiency. The analysis of surface properties demonstrated that all films possessed hydrophobic surface. Interestingly, SHP and SP addition greatly enhanced the antioxidant property of the films allowing them to be successfully used for food industries as bioactive packaging materials