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- ItemKaskadennutzung von Lignocellulose : LX-Verfahren trifft auf B. coagulans(Heidelberg : Spektrum, 2020) Schroedter, Linda; Streffer, Friedrich; Streffer, Katrin; Unger, Peter; Venus, JoachimInvestigating alternatives for petrobased substrates, lignocellulose is an interesting yet complex feedstock that offers various possibilities for the design of new and sustainable chemical routes. The novel energy-saving LX-pretreatment was combined with thermophilic Bacillus coagulans. By this, corn straw was used in an innovative cascade obtaining biogas, lignin as well as polymerisable L-(+)-lactic acid of over 99 percents optical purity. © 2020, Die Autoren.
- ItemExploitation of Ultrasound Technique for Enhancement of Microbial Metabolites Production(Basel : MDPI AG, 2020) Behzadnia, Asma; Moosavi-Nasab, Marzieh; Ojha, Shikha; Tiwari, Brijesh K.Microbial metabolites have significant impacts on our lives from providing valuable compounds for nutrition to agriculture and healthcare. Ever-growing demand for these natural compounds has led to the need for smart and efficient production techniques. Ultrasound is a multi-applicable technology widely exploited in a range of industries such as chemical, medical, biotechnological, pharmaceutical, and food processes. Depending on the type of ultrasound employed, it can be used to either monitor or drive fermentation processes. Ultrasonication can improve bioproduct productivity via intensifying the performance of living organisms. Controlled ultrasonication can influence the metabolites' biosynthesis efficiency and growth rates by improvement of cell permeability as well as mass transfer and nutrient uptake rates through cell membranes. This review contains a summarized description about suitable microbial metabolites and the applications of ultrasound technique for enhancement of the production of these metabolites as well as the associated downstream processing.
- ItemA simple biorefinery concept to produce 2g-lactic acid from Sugar Beet Pulp (SBP): A high-value target approach to valorize awaste stream(Basel : MDPI AG, 2020) De Oliveira, Regiane Alves; Schneider, Roland; Lunelli, Betânia Hoss; Rossell, Carlos Eduardo Vaz; Filho, Rubens Maciel; Venus, JoachimLactic acid is a high-value molecule with a vast number of applications. Its production in the biorefineries model is a possibility for this sector to aggregate value to its production chain. Thus, this investigation presents a biorefinery model based on the traditional sugar beet industry proposing an approach to produce lactic acid from a waste stream. Sugar beet is used to produce sugar and ethanol, and the remaining pulp is sent to animal feed. Using Bacillus coagulans in a continuous fermentation, 2781.01 g of lactic acid was produced from 3916.91 g of sugars from hydrolyzed sugar beet pulp, with a maximum productivity of 18.06 g L-1h-1. Without interfering in the sugar production, ethanol, or lactic acid, it is also possible to produce pectin and phenolic compounds in the biorefinery. The lactic acid produced was purified by a bipolar membrane electrodialysis and the recovery reached 788.80 g/L with 98% w/w purity. © 2020 by the authors.
- ItemProduction of Lactic Acid from Carob, Banana and Sugarcane Lignocellulose Biomass(Basel : MDPI AG, 2020) Azaizeh, Hassan; Abu Tayeh, Hiba N.; Schneider, Roland; Klongklaew, Augchararat; Venus, JoachimLignocellulosic biomass from agricultural residues is a promising feedstock for lactic acid (LA) production. The aim of the current study was to investigate the production of LA from different lignocellulosic biomass. The LA production from banana peduncles using strain Bacillus coagulans with yeast extract resulted in 26.6 g LA·L-1, and yield of 0.90 g LA·g-1 sugars. The sugarcane fermentation with yeast extract resulted in 46.5 g LA·L-1, and yield of 0.88 g LA·g-1 sugars. Carob showed that addition of yeast extract resulted in higher productivity of 3.2 g LA·L-1·h-1 compared to without yeast extract where1.95 g LA·L-1·h-1 was obtained. Interestingly, similar LA production was obtained by the end where 54.8 and 51.4 g·L-1 were obtained with and without yeast extract, respectively. A pilot scale of 35 L using carob biomass fermentation without yeast extract resulted in yield of 0.84 g LA·g-1 sugars, and productivity of 2.30 g LA·L-1·h-1 which indicate a very promising process for future industrial production of LA.
- ItemExperimental evaluation and application of genetic programming to develop predictive correlations for hydrochar higher heating value and yield to optimize the energy content(Amsterdam [u.a.] : Elsevier, 2022) Marzban, Nader; Libra, Judy A.; Hosseini, Seyyed Hossein; Fischer, Marcus G.; Rotter, Vera SusanneThe hydrothermal carbonization (HTC) process has been found to consistently improve biomass fuel characteristics by raising the higher heating value (HHV) of the hydrochar as process severity is increased. However, this is usually associated with a decrease in the solid yield (SY) of hydrochar, making it difficult to determine the optimal operating conditions to obtain the highest energy yield (EY), which combines the two parameters. In this study, a graph-based genetic programming (GP) method was used for developing correlations to predict HHV, SY, and EY for hydrochars based on published values from 42 biomasses and a broad range of HTC experimental systems and operating conditions, i.e., 5 ≤ holding time (min) ≤ 2208, 120 ≤ temperature (°C) ≤ 300, and 0. 0096 ≤ biomass to water ratio ≤ 0.5. In addition, experiments were carried out with 5 pomaces at 4 temperatures and two reactor scales, 1 L and 18.75 L. The correlations were evaluated using this experimental data set in order to estimate prediction errors in similar experimental systems. The use of the correlations to predict HTC conditions to achieve the maximum EY is demonstrated for three common feedstocks, wheat straw, sewage sludge, and a fruit pomace. The prediction was confirmed experimentally with pomace at the optimized HTC conditions; we observed 6.9 % error between the measured and predicted EY %. The results show that the correlations can be used to predict the optimal operating conditions to produce hydrochar with the desired fuel characteristics with a minimum of actual HTC runs.
- ItemEvaluation of Sonocatalytic and Photocatalytic Processes Efficiency for Degradation of Humic Compounds Using Synthesized Transition-Metal-Doped ZnO Nanoparticles in Aqueous Solution(New York, NY [u.a.] : Hindawi, 2021) Maleki, Afshin; Seifi, Mehran; Marzban, NaderThe existence of a humic substance in water causes the growth of microorganisms and reduces the quality of water; therefore, the removal of these materials is crucial. Here, the ZnO nanoparticles doped using transition metals, copper (Cu) and manganese (Mn), were used as an effective catalyst for photocatalytic removal of humic substances in an aqueous environment under ultraviolet, visible light, and light-emitting diode irradiations. Also, we study the effect of the sonocatalytic method. A solvothermal procedure is used for doping, and the Cu- and Mn-doped ZnO nanocatalyst were characterized by means of FTIR, XRD, AFM, SEM, and EDAX analyses. We investigate the effect of operational variables, including doping ratio, initial pH, catalyst dose, initial HS content, and illuminance on the removal efficiency of the processes. The findings of the analyses used for the characterization of the nanoparticles illustrate the appropriate synthesis of the Cu- and Mn-doped ZnO nanocatalysts. We observe the highest removal efficiency rate under acidic conditions and the process efficiency decreased with increasing solution pH, when we tested it in the range of 3–7. Photocatalytic decomposition of HS increases with a rise in catalyst dose, but an increase in initial HS content results in decreasing the removal efficiency. We observe the highest photocatalytic degradation of humic acid while using the visible light, and the highest removal efficiency is obtained using Cu.ZnO. The Cu.ZnO also shows better performance under ultraviolet irradiation compared to other agents.
- ItemTowards efficient production of highly optically pure d-lactic acid from lignocellulosic hydrolysates using newly isolated lactic acid bacteria(New York, NY [u.a.] : Elsevier, 2022) Alexandri, Maria; Hübner, Dennis; Schneider, Roland; Fröhling, Antje; Venus, JoachimThis study presents the production of D-lactic acid with high enantiomeric purity using lignocellulosic hydrolysates from newly isolated lactic acid bacterial (LAB) strains. Six strains, 4 heterofermentative and 2 homofermentative, were investigated for their ability to grow and produce lactic acid on sugar beet pulp (SBP) hydrolysates, containing a mixture of hexose and pentose sugars. Among the strains tested, three were isolates designated as A250, A257 and A15, all of which belonged to the genus Leuconostoc. Only strain A250 could be reliably identified as Leuconostoc pseudomesenteroides based on cluster analysis of Maldi-ToF spectra. All strains produced D-lactic acid in the presence of SBP hydrolysates, but with varying optical purities. The homofermentative strains achieved higher D-lactic acid optical purities, but without assimilating the pentose sugars. Co-cultivation of the homofermentative strain Lactobacillus coryniformis subsp. torquens DSM 20005 together with the heterofermentative isolate A250 led to the production of 21.7 g/L D-lactic acid with 99.3 % optical purity. This strategy enabled the complete sugar utilization of the substrate. Nanofiltration of the SBP hydrolysate enhanced the enantiomeric purity of the D-lactic acid produced from the isolates A250 and A15 by about 5 %. The highest D-lactic acid concentration (40 g/L) was achieved in fed-batch cultures of A250 isolate with nanofiltered SBP, where optical purity was 99.4 %. The results of this study underline the feasibility of a novel isolate as an efficient D-lactic acid producer using lignocellulosic hydrolysates.
- ItemIdentification and molecular analysis of interaction sites in the MtSEO-F1 protein involved in forisome assembly(New York, NY [u.a.] : Elsevier, 2020) Rose, Judith; Visser, Franziska; Müller, Boje; Senft, Matthias; Groscurth, Sira; Sicking, Kevin F.; Twyman, Richard M.; Prüfer, Dirk; Noll, Gundula A.Forisomes are large mechanoprotein complexes found solely in legumes such as Medicago truncatula. They comprise several “sieve element occlusion by forisome” (SEO-F) subunits, with MtSEO-F1 as the major structure-forming component. SEO-F proteins possess three conserved domains –an N-terminal domain (SEO-NTD), a potential thioredoxin fold, and a C-terminal domain (SEO-CTD)– but structural and biochemical data are scarce and little is known about the contribution of these domains to forisome assembly. To identify key amino acids involved in MtSEO-F1 dimerization and complex formation, we investigated protein-protein interactions by bimolecular fluorescence complementation and the analysis of yeast two-hybrid and random mutagenesis libraries. We identified a SEO-NTD core region as the major dimerization site, with abundant hydrophobic residues and rare charged residues suggesting dimerization is driven by the hydrophobic effect. We also found that ~45% of the full-length MtSEO-F1 sequence must be conserved for higher-order protein assembly, indicating that large interaction surfaces facilitate stable interactions, contributing to the high resilience of forisome bodies. Interestingly, the removal of 62 amino acids from the C-terminus did not disrupt forisome assembly. This is the first study unraveling interaction sites and mechanisms within the MtSEO-F1 protein at the level of dimerization and complex formation. © 2018
- ItemPrimarily tests of a optoelectronic in-canopy sensor for evaluation of vertical disease infection in cereals(New York, NY : Wiley, 2022) Dammer, Karl-Heinz; Schirrmann, MichaelBACKGROUND: Health scouting of crops by satellite, airplanes, unmanned aerial (UAV) and ground vehicles can only evaluate the crop from above. The visible leaves may show no disease symptoms, but lower, older leaves not visible from above can do. A mobile in-canopy sensor was developed, carried by a tractor to detect diseases in cereal crops. Photodiodes measure the reflected light in the red and infrared wavelength range at 10 different vertical heights in lateral directions. RESULTS: Significant differences occurred in the vegetation index NDVI of sensor levels operated inside and near the winter wheat canopy between infected (stripe rust: 2018, 2019 / leaf rust: 2020) and control plots. The differences were not significant at those sensor levels operated far above the canopy. CONCLUSIONS: Lateral reflectance measurements inside the crop canopy are able to distinguish between disease-infected and healthy crops. In future mobile in-canopy scouting could be an extension to the common above-canopy scouting praxis for making spraying decisions by the farmer or decision support systems. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.