Legumes as food ingredient: characterization, processing, and applications

Editores: Jiménez-López, José Carlos (CSIC); Clemente, Alfonso (CSIC

Insights into SusCD-mediated glycan import by a prominent gut symbiont

In Bacteroidetes, one of the dominant phyla of the mammalian gut, active uptake of large nutrients across the outer membrane is mediated by SusCD protein complexes via a “pedal bin” transport mechanism. However, many features of SusCD function in glycan uptake remain unclear, including ligand binding, the role of the SusD lid and the size limit for substrate transport. Here we characterise the β2,6 fructo-oligosaccharide (FOS) importing SusCD from Bacteroides thetaiotaomicron (Bt1762-Bt1763) to shed light on SusCD function. Co-crystal structures reveal residues involved in glycan recognition and suggest that the large binding cavity can accommodate several substrate molecules, each up to ~2.5 kDa in size, a finding supported by native mass spectrometry and isothermal titration calorimetry. Mutational studies in vivo provide functional insights into the key structural features of the SusCD apparatus and cryo-EM of the intact dimeric SusCD complex reveals several distinct states of the transporter, directly visualising the dynamics of the pedal bin transport mechanism

CARBOHYDRATE POLYMERS

Levan production in batch and continuous fermentation systems by Zymomonas mobilis B-14023 was investigated. The culture medium used in both of the fermentation systems contained sucrose and various organic nitrogen sources. Maximum concentration of levan was produced with yeast extract among the nitrogen sources tested. Response surface methodology was used to investigate the effects of three factors on the concentration of levan in batch cultures of Z. mobilis. Maximum levan concentration was 40.2 g/L and this concentration was reached at the optimum levels of process variables, which were 299.1 g/L initial substrate concentration, 42.3 h incubation time, and initial pH 6.0. Continuous fermentation experiments were done in packed bed bioreactor using Ca-alginate immobilized Z. mobilis cells. The highest levan concentration (31.8 +/- 0.21 g/L) was obtained at a dilution rate of 0.14 h(-1) while maximum volumetric productivity (6.556 g/(Lh)) was obtained at a dilution rate of 0.22 h(-1). Increasing the dilution rate resulted in decreased levan and increased residual sugar concentrations. (C) 2013 Elsevier Ltd. All rights reserved

Natural red pigment production by monascus purpureus in submerged fermentation systems using a food industry waste: Brewer's spent grain

This paper studies the production of natural red pigments by Monascus purpureus CMU001 in the submerged fermentation system using a brewery waste hydrolysate, brewer's spent grain (BSG). The chemical, structural and elemental characterization of the BSG was performed with Van-Soest method, Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), respectively. The lignocellulosic structure of BSG was hydrolyzed with a dilute sulfuric acid solution (2% (w/v)) followed by detoxification with Ca(OH)2. Maximum red pigment production (22.25 UA500) was achieved with the following conditions: 350 rpm shake speed, 50 mL fermentation volume, initial pH of 6.5, inoculation ratio of 2% (v/v), and monosodium glutamate (MSG) as the most effective nitrogen source. Plackett-Burman design was used to assess the significance of the fermentation medium components, and MSG and ZnSO47H2O were found to be the significant medium variables. This study is the first study showing the compatibility of BSG hydrolysate to red pigment production by Monascus purpureus in a submerged fermentation system. © 2019 MDPI Multidisciplinary Digital Publishing Institute. All rights reserved.Ege Üniversitesi: 16-MÜH-031 16-MUH-031ammonia, which increased the pH of the fermentation broth. Author Contributions: Conceptualization, Y.G.; Methodology, S.S. and Y.G.; Validation, Y.G. and S.S.; Data Curation, S.S. and Y.G.; Writing-Original Draft Preparation, S.S.; Writing-Review and Editing, Y.G. 4. Conclusions Funding: This research was funded by the EGE UNIVERSITY SCIENTIFIC RESEARCH PROJECT FOUNDATION, 16-MÜH-031.Monascus pigments have received worldwide attention for their multiple health benefits; they appear to have anti-mutagenic, anti-cancer, anti-obesity, anti-inflammation, anti-diabetes, and Acknowledgments: We appreciate Ege University Scientific Research Project Fund (Project No: 16-MUH-031) cholesterol-lowering mechanisms. This research article is the first on the evaluation of hydrolyzed for supporting this research. The researchers are thankful to Professor Saisamorn Lumyong for providing the and detoxified brewer’s spent grain for red pigment production by Monascus purpureus in submerged Perendeci and Laboratory of Environmental Biotechnology of Akdeniz University for opening their laboratory and supporting the Van Soest analysis and Huriye Goksungur for proofreading the manuscript. -