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• β -galactosidase was immobilized on chitosan-coated magnetic nanoparticles. • Optimization of immobilization process was done for maximizing yield. • The immobilization increased the stability of enzyme preparation. • Kinetic constants of both free and immobilized enzyme preparations were determined. • Long-term bioconversion for production of lactulo-oligosaccharides was tested. β -Galactosidase was covalently immobilized on the chitosan-coated magnetic nanoparticles activated with glutaraldehyde. The effect of three factors including protein content, pH and time on the yield of immobilization was investigated, and the optimum values were 0.45 mg/ml, 4.9 and 4.9 h, respectively. The maximum yield of immobilization reached 98.8% in term of enzyme activity. The stability of β -galactosidase significantly was improved after immobilization from 2.5 days to over 6 days of half-life at 60 °C and was active in wider ranges of temperature (45–60 °C), and pH (4.0–5.5) compared to soluble form. The activity of immobilized enzyme remained 85% of origin after eight recycles (at 60 °C, pH 4.5 for 4 h). Different initial lactulose concentrations (0.58–2.34 M) were applied for synthesis of galactooligosaccharides. The maximum yield of galactooligosaccharides was 17% mol/mol at the initial lactulose concentration of 2.34 M at 36 h of reaction. It showed that both hydrolytic and trans-galactosylation activities of β -galactosidase remained well after immobilization. The kinetic model of immobilized enzyme was determined. These results revealed that immobilized enzyme on chitosan-coated magnetic nanoparticles has application potentials in the production of prebiotic lactulose-based galactooligosaccharides. [ABSTRACT FROM AUTHOR]

The commercial enzymatic preparation, Pectinex Ultra SP-L, was successfully immobilized on activated chitosan particles for production of lactulose-based galacto-oligosaccharide (LuOS). The main degrees of polymerization (DP) of LuOS produced in this bioreactor were DP3 and DP4. The immobilization yield in term of expressed activity and recovery activity were 71% and 36.05%, respectively. The optimum temperature (60° C) was not affected by immobilization process, while the optimum pH was shifted from pH 5.5 to pH 4.5. In addition, a thermal stability of the immobilized enzyme was better than th a t of free enzyme. The half-life time of hydrolytic activity increased from 2.5 days (free enzyme) to 14 days (immobilized enzyme). Hydrolytic KM values were 651.3 mM and 187.9 mM lactulose for free enzyme and immobilized enzyme, respectively. Furthermore, the immobilized enzyme showed high reusability. The yield of LuOS formation was more than 60% after 33 cycles of reuses. In the case of trans-galactosylation, a model with 8 reaction rates was build using five-step reaction pathways with different initial lactulose concentrations. This catalytic model was validated well for a long-term period (27 days). These results strongly support to develop a continuous bioconversion to synthesize functional food ingredients, prebiotic LuOS. [ABSTRACT FROM AUTHOR]

Poster: Physics track: Radiobiological and predictive modelling, and radiomics PO-1563: New voxel-based approach to study the relation of tumor location and survival in NSCLC (SAKK-16/00) D. Vuong, M. Bogowicz, J. Unkelbach, S. Hillinger, S. Thierstein, E.I. Eboulet, S. Peters, M. Pless, M. Guckenberger, S. Tanadini-Lang. [Extracted from the article]

Background: Vendor-independent Monte Carlo (MC) dose calculation (IDC) for patient-specific quality assurance of multi-leaf collimator (MLC) based CyberKnife treatments is used to benchmark and validate the commercial MC dose calculation engine for MLC based treatments built into the CyberKnife treatment planning system (Precision MC).Methods: The benchmark included dose profiles in water in 15 mm depth and depth dose curves of rectangular MLC shaped fields ranging from 7.6 mm × 7.7 mm to 115.0 mm  × 100.1 mm, which were compared between IDC, Precision MC and measurements in terms of dose difference and distance to agreement. Dose distributions of three phantom cases and seven clinical lung cases were calculated using both IDC and Precision MC. The lung PTVs ranged from 14 cm3 to 93 cm3. Quantitative comparison of these dose distributions was performed using dose-volume parameters and 3D gamma analysis with 2% global dose difference and 1 mm distance criteria and a global 10% dose threshold. Time to calculate dose distributions was recorded and efficiency was assessed.Results: Absolute dose profiles in 15 mm depth in water showed agreement between Precision MC and IDC within 3.1% or 1 mm. Depth dose curves agreed within 2.3% / 1 mm. For the phantom and clinical lung cases, mean PTV doses differed from - 1.0 to + 2.3% between IDC and Precision MC and gamma passing rates were > =98.1% for all multiple beam treatment plans. For the lung cases, lung V20 agreed within ±1.5%. Calculation times ranged from 2.2 min (for 39 cm3 PTV at 1.0 × 1.0 × 2.5 mm3 native CT resolution) to 8.1 min (93 cm3 at 1.1 × 1.1 × 1.0 mm3), at 2% uncertainty for Precision MC for the 7 examined lung cases and 4-6 h for IDC, which, however, is not optimized for efficiency but used as a gold standard for accuracy.Conclusions: Both accuracy and efficiency of Precision MC in the context of MLC based planning for the CyberKnife M6 system were benchmarked against MC based IDC framework. Precision MC is used in clinical practice at our institute. [ABSTRACT FROM AUTHOR]

Pig shoulder bones, by‐products from the meat industry, are rich in protein and could be used to produce high amino acid products for food processing. In this study, after formulating the bone soup by heating it in water, we optimized the hydrolyzing process of the bone soup using three commercial enzymes (Flavourzyme, Protamex, and Alcalase). Alcalase hydrolysis gained the highest soluble protein recovery efficiency of 70.45% at the optimum condition, including hydrolysis temperature of 56°C, hydrolysis time of 138 min, and E/S ratio of 2.3%. The Alcalase hydrolysate achieved the peptide average molecular weight of 532 Da. In terms of nutritional value, the amino acid content gradually increased from the samples hydrolyzed with Alcalase, Flavourzyme, and Protamex (15.96, 16.60, and 20.71 mg/ml, respectively). However, the hydrolysate using Alcalase was the most favorable sample in sensory evaluation. Novelty Impact Statement: Optimized soluble protein recovery of amino acids and peptides via enzymatic hydrolysis is essential to attain the highest possible nutritional value from raw materials like pig bone. Besides, thermal pretreatment and fat removal were implemented to identify soluble protein recovery efficiency (SPRE) precisely. [ABSTRACT FROM AUTHOR]

Background: Careful selection of malignant pleural mesothelioma (MPM) patients for curative treatment is of highest importance, as the multimodal treatment regimen is challenging for patients and harbors a high risk of substantial toxicity. Radiomics—a quantitative method for image analysis—has shown its prognostic ability in different tumor entities and could therefore play an important role in optimizing patient selection for radical cancer treatment. So far, radiomics as a prognostic tool in MPM was not investigated. Materials and methods: This study is based on 72 MPM patients treated with surgery in a curative intent at our institution between 2009 and 2017. Pre-treatment Fluorine-18 fluorodeoxyglucose (FDG) PET and CT scans were used for radiomics outcome modeling. After extraction of 1404 CT and 1410 FDG PET features from each image, a preselection by principal component analysis was performed to include only robust, non-redundant features for the cox regression to predict the progression-free survival (PFS) and the overall survival (OS). Results were validated on a separate cohort. Additionally, SUVmax and SUVmean, and volume were tested for their prognostic ability for PFS and OS. Results: For the PFS a concordance index (c-index) of 0.67 (95% CI 0.52–0.82) and 0.66 (95% CI 0.57–0.78) for the training cohort (n = 36) and internal validation cohort (n = 36), respectively, were obtained for the PET radiomics model. The PFS advantage of the low-risk group translated also into an OS advantage. On CT images, no radiomics model could be trained. SUV max and SUV mean were also not prognostic in terms of PFS and OS. Conclusion: We were able to build a successful FDG PET radiomics model for the prediction of PFS in MPM. Radiomics could serve as a tool to aid clinical decision support systems for treatment of MPM in future. [ABSTRACT FROM AUTHOR]

• Crude enzyme preparation from Bifidobacterium has glycosyltransylation activities. • Gluco - and galactooligosaccharides are formulated in bioconversion on bisubstrates. • Two new types of oligosaccharides were synthetized using crude enzyme preparation. • One new type of galactooligosaccharide has high prebiotic potential. Oligosaccharides especially prebiotics take high attention in the development of foods because of their physiological properties in human health. They are generally synthetized enzymatically via transferases or hydrolases from mold or bacteria. The fact is that such oligosaccharides synthetized by probiotic bacteria, should be utilized by these microorganisms. This study focused on the production of oligosaccharides with prebiotic potential by crude enzyme preparation from bifidobacteria. Both monosubstrates and bisubstrates systems together with TLC and HPLC techniques, were applied. The crude enzyme preparation has different hydrolase activities such as α-glucosidase (2U/mL), β-glucosidase (0.3 U/mL), α-galactosidase (1.2 U/mL), β-galactosidase (0.4 U/mL), β-fructosidase (11.5 U/mL). Additionally, it also has transglycosylation activities on lactose, lactulose, maltose and sucrose substrates. Two or three types of oligosaccharides were detected. The glycosyltransferase activity peaked at 45 °C, pH 6.6 and 30 g/100 mL substrate concentration. Significant high amount of oligosaccharides were formed in the case of lactose:sucrose combination than others. Both glucooligosaccharides and galactooligosaccharides are detected in the reaction mixtures of bisubstrate. When the lactose is present, the galactosyltransferation is predominated. One-one new types of oligosaccharides were detected in the reaction mixture of bioconversion. Among newly synthetized oligosaccharides, the fraction namely OS4 was utilized by probiotic bifidobacteria only. In conclusion, new types of galacto- and glucooligosaccharides with high prebiotic potentials were synthetized by the crude enzyme from probiotic Bifidobacterium strains. [ABSTRACT FROM AUTHOR]

• New conductive polymers composites were successfully synthetized and characterised. • Conditions for fabrication of conductive hydrogels were optimised and validated. • Bacteria cells were immobilised into composites and new bio-anode was formed. • Application of new bio-anode improved both power density and stability of the MFC. The electrical conducting bacterial cellulose/polyaniline (BC/PANI) based composites were synthesized over in situ polymerization of aniline onto BC with ammonium-persulphate (APS) and chloride hexahydrate of iron (III) as oxidant (FeCl 3 ·6H 2 O). The conductivity of synthesized BC was improved in the presence of a titanium-dioxide (TiO 2) coating. The conductivity of BC/PANI/TiO 2 /APS was 3.7 S/m compare 2.9 S/m and 2.67 S/m with BC/PANI/TiO 2 /FeCl 3 ·6H 2 O and BC/PANI/APS, respectively. Moreover, when using the BC/PANI/TiO 2 /APS as anode with the immobilization of Shewanella xiamenensis , an improved efficiency of microbial fuel cell was observed. The power-density maximized 38.89 W/m3 with BC/PANI/TiO 2 /APS anode compared with 2.57 W/m3 in the case of bare BC anode. These results will serve as a good base for the development of compact microbial fuel cell with high power density. [ABSTRACT FROM AUTHOR]

The deinking ability of chitosan-based particles in the pretreatment of recycling paper was studied. All these polymers were able to adsorb carbon black as ink pigment. Amount of adsorbents, contact time, solution pH and temperature were optimized to estimate maximum sorption capacity of polymers. The optimum condition of carbon black adsorption was achieved using chitosan-coated Ca-alginate beads at 30 min, 35 °C, pH 6.5 and 220 rpm of agitation speed. The adsorption capacity was more than 80%. Packed-bed reactor filled with chitosan-coated alginate beads was conducted and operated under the optimal conditions. More than 95% of ink was adsorbed onto carriers after 20 h. Saccharification with industrial enzyme preparation of deinked paper pulp was carried out and sugars released were converted into ethanol. The results of alcoholic fermentation confirmed the success of the deinking process. Our results are very promising in the development of pretreatment technology to enhance the efficiency of the utilization of recycling paper. [ABSTRACT FROM AUTHOR]

Poster: Physics track: Radiobiological and predictive modelling, and radiomics PO-1571: Radiomics for prediction of metastatic melanoma patient survival after immunotherapy H. Gabrys, L. Basler, S. Hogan, M. Pavic, M. Bogowicz, D. Vuong, S. Tanadini-Lang, R. Förster, M. Huellner, R. Dummer, M. Guckenberger, M.P. Levesque. [Extracted from the article]