Biocompounds from rapeseed oil industry co-stream as active ingredients for skin care applications.

OBJECTIVE: Despite the great number of substances produced by the skincare industry, very few of them seem to truly have an effect on the skin. Therefore, given the social implications surrounding physical appearance, the search for new bioactive compounds to prevent or attenuate skin ageing and enhance self-image is a priority of current research. In this context, being rich in valuable compounds, such as proteins, phenolics, lipids and vitamins, this study is focused on the potential activity of rapeseed press cake hydrolysates to be used as raw materials for skincare applications. METHODS: In this study, the protein-rich press residue from the rapeseed oil industry was converted enzymatically into short-chain biologically active peptides using four protease products with varying substrate specificity - Alcalase 2.4L FG, Protex 6L, Protamex and Corolase 7089. The antioxidant, anti-wrinkle and anti-inflammatory activities of the obtained hydrolysates were evaluated in vitro while their biocompatibility with human skin fibroblasts was tested. RESULTS: All hydrolysates were biocompatible with skin fibroblasts after 24 h of exposure, while the non-hydrolysed extract induced cell toxicity. Alcalase 2,4L FG and Protex 6L-obtained hydrolysates were the most promising extracts showing improved bioactivities suitable for skin anti-ageing formulations, namely antioxidant activity, inhibiting approximately 80% cellular reactive oxidative species, anti-inflammatory and anti-wrinkle properties, inhibiting around 36% of myeloperoxidase activity and over 83% of elastase activity. CONCLUSION: The enzymatic technology applied to the rapeseed oil industry costream results in the release of bioactive compounds suitable for skincare applications.

Multifunctional piezoelectric surfaces enhanced with layer-by-layer coating for improved osseointegration and antibacterial performance.

Implant failure is primarily caused by poor osseointegration and bacterial colonization, which demands readmissions and revision surgeries to correct it. A novel approach involves engineering multifunctional interfaces using piezoelectric polyvinylidene fluoride (PVDF) materials, which mimic bone tissue's electroactive properties to promote bone integration and provide antibacterial functionality when mechanically stimulated. In this study, PVDF films were coated with antibacterial essential oil nanoparticles and antibiofilm enzymes using a layer-by-layer (LBL) approach to ensure antibacterial properties even without mechanical stimulation. The experimental results confirmed the LBL build-up and demonstrated notable antibiofilm properties against Pseudomonas aeruginosa and Staphylococcus aureus while enhancing pre-osteoblast cell proliferation under mechanical dynamic conditions in a bioreactor that replicated the real-life environment of implants within the body. The findings highlight the potential of PVDF-coated surfaces to prevent biofilm formation and boost cell proliferation through the piezoelectric effect, paving the way for advanced implantable devices with improved osseointegration and antibacterial performance.

Comparative study of the efficiency of synthetic and natural mediators in laccase-assisted bleaching of eucalyptus kraft pulp.

The natural phenolic compounds syringaldehyde and vanillin were compared to the synthetic mediators 1-hydroxybenzotriazole, violuric acid and promazine in terms of boosting efficiency in a laccase-assisted biobleaching of eucalyptus kraft pulp. Violuric acid and 1-hydroxybenzotriazole revealed to be the most effective mediators of the bioprocess. Nevertheless, laccase-syringaldehyde system also improved the final pulp properties (28% delignification and 63.5% ISO brightness) compared to the process without mediator (23% and 61.5% respectively), in addition to insignificant denaturation effect over laccase. The efficiency of the biobleaching process was further related to changes in non-conventionally used optical and chromatic parameters of pulp, such as (L*), chroma (C*) and dye removal index (DRI) showing good correlation. Adverse coupling reactions of the natural phenolic mediators on pulp lignin were predicted by electrochemical studies, demonstrating the complexity of the laccase-mediator reaction on pulp.

Thermo-alkali-stable catalases from newly isolated Bacillus sp. for the treatment and recycling of textile bleaching effluents.

Three thermoalkaliphilic bacteria, which were grown at pH 9.3-10 and 60-65 degrees C were isolated out of a textile wastewater drain. The unknown micro-organisms were identified as thermoalkaliphilic Bacillus sp. Growth conditions were studied and catalase activities and stabilities compared. Catalases from Bacillus SF showed high stabilities at 60 degrees C and pH 9 (t1/2=38 h) and thus this strain was chosen for further investigations, such as electron microscopy, immobilization of catalase and hydrogen peroxide degradation studies. Degradation of hydrogen peroxide with an immobilized catalase from Bacillus SF enabled the reuse of the water for the dyeing process. In contrast, application of the free enzyme for treatment of bleaching effluents, caused interaction between the denaturated protein and the dye, resulting in reduced dye uptake, and a higher color difference of 1.3DeltaE* of dyed fabrics compared to 0.9DeltaE* when using the immobilized enzyme.

In situ chitosan gelation initiated by atmospheric plasma treatment.

This work reports on the feasibility of atmospheric dielectric barrier discharge (DBD) plasma as a novel synthetic pathway for the liquid phase gelation of chitosan. The DBD plasma chitosan gelation process did not significantly alter the chemical structure of the biopolymer as confirmed by FTIR study. However, the oxidation processes and local heating effect associated with the solvent evaporation during the plasma treatment could provoke both reaction of chitosan degradation and the cleavage of ß-1-4-glycosidic linkages with the concomitant generation of aldehyde groups able to crosslink via Schiff-base with amino groups from other chitosan molecules. Shear viscosity measurements suggested the formation of chitosan fragments of lower molecular weight after the plasma treatment of 1% (w/v) chitosan and fragments of higher molecular weight after the plasma treatment of 2% (w/v) chitosan. The crosslinking density of hydrogels generated during the in situ DBD plasma chitosan gelation process increased as a function of the treatment time and concentration of chitosan. As of consequence of the increase of the cross-linking density, the equilibrium swelling ratio and water content decreased significantly.

Spontaneous rosette formation in patients with oral cancer.

The percentage of "total" E-rosettes was studied in the peripheral blood of 38 untreated patients with squamous cell carcinoma of the oral cavity, performing the test at 4 degrees C and at 20 degrees C. At 4 degrees C the quantity of the E-rosettes was higher than at 20 degrees C. The mean value of E-rosettes was strongly reduced only in 17 of these patients with metastases in the regional lymph nodes when compared with a group of 40 normal individuals as well as with the group of remaining 21 patients with localized cancer (P less than 0.001), whatever the temperature of testing. The mean percentage of 20 degrees C E-rosettes was significantly higher in patients with localized disease than in the 22 normal donors (50.2 +/- 3.0% vs 41.8 +/- 2.0%, P less than 0.01) but in favour of 4 degrees C E-rosettes the difference was not significant (57.3 +/- 2.8% vs 54.2 +/- 2.9%). Thus there was a clear correlation between changes of the T cell level and the clinical stage of the disease.

Decolorization and detoxification of textile dyes with a laccase from Trametes hirsuta.

Trametes hirsuta and a purified laccase from this organism were able to degrade triarylmethane, indigoid, azo, and anthraquinonic dyes. Initial decolorization velocities depended on the substituents on the phenolic rings of the dyes. Immobilization of the T. hirsuta laccase on alumina enhanced the thermal stabilities of the enzyme and its tolerance against some enzyme inhibitors, such as halides, copper chelators, and dyeing additives. The laccase lost 50% of its activity at 50 mM NaCl while the 50% inhibitory concentration (IC(50)) of the immobilized enzyme was 85 mM. Treatment of dyes with the immobilized laccase reduced their toxicities (based on the oxygen consumption rate of Pseudomonas putida) by up to 80% (anthraquinonic dyes). Textile effluents decolorized with T. hirsuta or the laccase were used for dyeing. Metabolites and/or enzyme protein strongly interacted with the dyeing process indicated by lower staining levels (K/S) values than obtained with a blank using water. However, when the effluents were decolorized with immobilized laccase, they could be used for dyeing and acceptable color differences (DeltaE*) below 1.1 were measured for most dyes.

Immobilization of catalases from Bacillus SF on alumina for the treatment of textile bleaching effluents.

A catalase preparation from a newly isolated Bacillus sp. was covalently immobilized on silanized alumina using glutaraldehyde as crosslinking agent. The effect of the coupling time of the enzyme-support reaction was determined in terms of protein recovery and immobilization yield and a certain balance point was found after which the activity recovery decreased. The activity profile of the immobilized catalase at high pH and temperature was investigated. The immobilized enzyme showed higher stabilities (214 h at pH 11, 30 degrees C) at alkaline pH than the free enzyme (10 h at pH 11, 30 degrees C). The immobilized catalase was inhibited by anionic stabilizers or surfactants added to the hydrogen peroxide substrate solution.