Evaluation of a bacterial single-cell protein in compound diets for rainbow trout (Oncorhynchus mykiss) fry as an alternative protein source

A 60-day trial was conducted in rainbow trout (Oncorhynchus mykiss) fry (initial weight = 2.5 ± 0.6 g) to evaluate the potential use of a bacterial single-cell protein (SCP) as an alternative protein source. Five experimental diets with different levels of fishmeal replacement (0, 25, 50, 75 and 100%) and no amino acid supplementation were tested. At the end of the trial, we found that fry fed diets, replacing 25 and 50% of fishmeal with bacterial SCP, were 9.1 and 21.8% heavier, respectively, than those fed the control diet (p 50%), which was associated to feed palatability. High levels of bacterial SCP (>50%) affected the muscular amino acid and fatty acid profiles, imbalances that were associated to their dietary content. The broken-line regression analysis using muscle DHA content and weight gain data showed that the maximum levels of fishmeal replacement by bacterial SCP were 46.9 and 52%, respectively.info:eu-repo/semantics/publishedVersio

Physicochemical and Biochemical Properties of Trypsin-like Enzyme from Two Sturgeon Species

This work aimed to determine the physicochemical and biochemical properties of trypsin from beluga Huso huso and sevruga Acipenser stellatus, two highly valuable sturgeon species. According to the results obtained from the methods of casein-zymogram and inhibitory activity staining, the molecular weight of trypsin for sevruga and beluga was 27.5 and 29.5 kDa, respectively. Optimum pH and temperature values for both trypsins were recorded at 8.5 and 55 °C by BAPNA (a specific substrate), respectively. The stability of both trypsins was well-preserved at pH values from 6.0 to 11.0 and temperatures up to 50 °C. TLCK and SBTI, two specific trypsin inhibitors, showed a significant inhibitory effect on the enzymatic activity of both trypsins (p 0.05). The results of our study show that the properties of trypsin from beluga and sevruga are in agreement with data reported in bony fish and can contribute to the clear understanding of trypsin activity in these primitive species.info:eu-repo/semantics/publishedVersio

Effect of Amino-Functionalization on Insulin Delivery and Cell Viability for Two Types of Silica Mesoporous Structures

Inorganic Mesoporous Structures Are a Class of Novel Biomaterials that Have Shown Practical Applications in Delivery of a Variety of Therapeutic Agents. in the Present Study, Two Mesoporous Structures Were Prepared, and the Effect of Surface Modification on their Insulin Delivery and in Vitro Cytotoxicity Was Evaluated. Morphological and Structural Characterizations of Silica Particles Were Accomplished by Different Analytical Techniques, Including Scanning Electron Microscopy, X-Ray Diffraction, Fourier Transform Infrared Spectroscopy (FTIR), and Brunauer–Emmett–Teller (BET) Surface Area Analyses. the Drug Loading Capacity and in Vitro Drug Release Behavior of Silica Structures Were Investigated under Simulated Gastrointestinal Conditions and Phosphate-Buffered Saline Solution using FTIR and UV–Vis Spectroscopy. in Vitro Cytotoxicity Evaluation Was Carried Out Via MTT Assay. Results Showed that the Morphology of MCM-41 Was Round, While SBA-15 Was Wheat Like, Both Possessed Almost Homogeneous Size Distribution. Also, Modification with Amine Did Not Influence the Morphology and Structure of the Particles. Both MCM-41 and SBA-15 Particles Were Found to Have Narrow Pore-Size Distributions of 2.8 and 6.8 Nm, Respectively. SBA-15 Particles Demonstrated a High Insulin Loading Capacity of About 15.1 %, While MCM-41 and Modified MCM-41 (MMCM-41) Were Observed to Load Virtually No Insulin at All. the Surface Modification by Amino Groups Resulted in Higher Insulin Loading and the Slower Rate of Release for Modified SBA-15 (MSBA-15) Compared to the Non-Modified SBA-15 (SBA-15). According to the Cytotoxicity Evaluation Results, All of the Samples Showed Cytotoxicity Grade 0–1, in a Concentration-Dependent Manner. Moreover, Insulin-Loaded MSBA-15 Particles Exhibited Higher Cell Viability Compared to the Others. It Was Concluded that Amine Modification of SBA-15 Could Result in Higher Loading and Extended Release of Insulin and More Cell Viability

Fabrication and Characterization of Methylprednisolone-Loaded Polylactic Acid/Hyaluronic Acid Nanofibrous Scaffold for Soft Tissue Engineering

Previous in vitro and in vivo studies have indicated that tissue engineering scaffolds, including Schwann cells, may improve axonal regeneration, particularly in combination with Methylprednisolone as an influential neuroprotective factor. The primary aim of this study was to design composite electrospun scaffolds based on polylactic acid (PLA)/ hyaluronic acid (HA) containing various percentages (0.05–2% (w/v)) of Methylprednisolone (MP) with suitable mechanical and chemical properties for soft tissue especially to promote nerve growth. For the first time, MP was implicated in a PLA/HA nanofibrous and its effect on fiber’s properties was scrutinized as a candidate for nerve tissue

Genipin-crosslinked gelatin hydrogel incorporated with PLLA-nanocylinders as a bone scaffold: Synthesis, characterization, and mechanical properties evaluation

Nowadays, despite remarkable progress in developing bone tissue engineering products, the fabrication of an ideal scaffold that could meet the main criteria, such as providing mechanical properties and suitable biostability as well as mimicking the bone extracellular matrix, still seems challenging. In this regard, utilizing combinatorial approaches seems more beneficial. Here, we aim to reinforce the mechanical characteristics of gelatin hydrogel via a combination of Genipin-based chemical cross-linking and incorporation of the poly l-lactic acid (PLLA) nanocylinders for application as bone scaffolds. Amine-functionalized nanocylinders are prepared via the aminolysis procedure and incorporated in gelatin hydrogel. The nanocylinder content (0, 1, 2, 3, and 4 wt) and cross-linking density (0.1, 0.5, and 1 wt/vol) are optimized to achieve suitable morphology, swelling ratio, degradation rate, and mechanical behaviors. The results indicate that hydrogel scaffold cross-linking by 0.5 wt of Genipin shows optimized morphological feathers with a pore size of around 300 to 500 μm as well as an average degradation rate (40.09 ± 3.08) during 32 days. Besides, the incorporation of 3 wt PLLA nanocylinders into the cross-linked gelatin scaffold provides an optimized mechanical reinforcement as compressive modulus, and compressive strength show a 4- and 2.6-fold increase, respectively. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicates that the scaffold does not have any cytotoxicity effect. In conclusion, gelatin composite reinforced with 3 wt PLLA nanocylinders cross-linked via 0.5 wt/vol Genipin is suggested as a potential scaffold for bone tissue engineering applications. © 2020 John Wiley & Sons Lt

Effects of vaccination on acute-phase protein response in broiler chicken.

Broiler chickens experience an acute-phase response (APR) through vaccination, which reflects the innate immunity and stress related to immunization. It is also considered that APR can modulate adaptive immunity and response to infection. As biomarkers for APR, assessing the acute-phase proteins (APPs) function and their levels in response to immunization is of great value for vaccine design, development and administration. In this study, the heterophils/lymphocyte (H/L) ratio and the level of APPs was evaluated in broilers with three different Newcastle disease (ND) vaccination regimens. Inactivated ND vaccine (IND) was administered by the intramuscular route. Live attenuated strains, Lasota and Vitapest, was administered by ocular routes. H/L ratio, serum amyloid A (SAA) and alpha-1 acid glycoprotein (AGP) were measured before and after two rounds of vaccination on days 10 and 21. In a comparison between the three vaccines, H/L ratio in IND group significantly increased to 3 fold (1.48 ± 0.41) after the first vaccination while the Lasota and Vitapest showed a milder response. The concentration of SAA increased after 24h by 1.8-fold in IND group (0.116 ± 0.015 mg/L) and 2-fold in Lasota group (0.14 ± 0.002 mg/L). Significant changes were found in Vitapest group after 48h post vaccination (0.113 ± 0.016 mg/L). Elevation pattern of AGP, 24 hours after first vaccination in IND (3.5-fold) and Vitapest (2.5-fold) was different from Lasota in which the peak was reached after 48 hours (2.9-fold). Except for IND group, no significant changes in SAA and AGP concentrations were detected after the second vaccination. A significant positive correlation between SAA values at day 22 and HI titers at day 28 (r = 0.998, P≤0. 0.005) was found. According to these results, different types of ND vaccines can cause different patterns of acute phase responses. Assessment of stress and level of acute-phase proteins can be used for prediction of immune response outcomes in vaccine design and development

Effect of Gamma Irradiation on Structural and Biological Properties of a PLGA-PEG-Hydroxyapatite Composite

Gamma irradiation is able to affect various structural and biological properties of biomaterials In this study, a composite of Hap/PLGA-PEG and their ingredients were submitted to gamma irradiation doses of 25 and 50 KGy. Various properties such as molecular weight (GPC), thermal behavior (DSC), wettability (contact angle), cell viability (MTT assay), and alkaline phosphatase activity were studied for the composites and each of their ingredients. The results showed a decrease in molecular weight of copolymer with no change in the glass transition and melting temperatures after gamma irradiation. In general gamma irradiation can increase the activation energy ΔH of the composites and their ingredients. While gamma irradiation had no effect on the wettability of copolymer samples, there was a significant decrease in contact angle of hydroxyapatite and composites with increase in gamma irradiation dose. This study showed an increase in biocompatibility of hydroxyapatite with gamma irradiation with no significant effect on cell viability in copolymer and composite samples. In spite of the fact that no change occurred in alkaline phosphatase activity of composite samples, results indicated a decrease in alkaline phosphatase activity in irradiated hydroxyapatites. These effects on the properties of PLGA-PEG-hydroxyapatite can enhance the composite application as a biomaterial