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Records with Subject: Biosystems
Showing records 101 to 125 of 204. [First] Page: 1 2 3 4 5 6 7 8 9 Last
Hollow and Solid Spherical Azithromycin Particles Prepared by Different Spherical Crystallization Technologies for Direct Tableting
Kui Chen, Baohong Hou, Hao Wu, Xin Huang, Fei Li, Yan Xiao, Jing Li, Ying Bao, Hongxun Hao
July 30, 2019 (v1)
Subject: Biosystems
Keywords: azithromycin, counter diffusion, immersion, powder property, spherical particles
Many drugs have a propensity for agglomeration, resulting in poor flowability. Spherical crystallization can be used to improve product properties including flowability and particle size. In this work, two methods were developed and utilized to successfully make two kinds of azithromycin spherical particles, namely solid and hollow spheres. The resultant product exhibited regular spherical shape, large particle size, narrow particle size distribution and excellent flowability. The formation mechanism of these different spherical crystals was investigated with the help of a particle vision microscope (PVM). The immersion mechanism and the counter diffusion mechanism were proposed as the formation mechanisms for solid and hollow spheres, respectively. The effects of crystallization parameters on the spherical crystallization processes were investigated systematically. Furthermore, the tablet properties were evaluated to verify that the spherical particles obtained in this work can be dir... [more]
Optimization of Ultrasound-Assisted Extraction on Antioxidative Activity of Malus toringoides Using Response Surface Methodology
Qiang Ye, Li Guo, Hongmei Liu, Yushi Liu, Cunyan Zhang, Cheng Peng, Zhiming Liu, Shan Huang, Bin Li
July 30, 2019 (v1)
Subject: Biosystems
Keywords: human umbilical vein endothelial cells, M.toringoides, protection rate, response surface methodology, ultrasonic-assisted extraction
Ultrasonic-assisted extraction (UAE) was optimized using response surface methodology (RSM) to maintain the cyto-protective activity of M.toringoides against oxidative stress. The optimal conditions for UAE were a 58 mL/g liquid-solid ratio, a 38 °C extraction temperature, an 85% solvent concentration, and a 19-min extraction time, which resulted in a protection rate of 54.57% against hydrogen peroxide-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). These results were comparable to the predicted value of 53.75%. The extracts showed excellent antioxidant activity, and phlorizin was detected in the dried leaves of Malus.toringoides. The highest yield of phlorizin (101.239 mg/g) was also obtained using these conditions. Taken together, these results showed that the method successfully integrated RSM and partial least squares regression methods to optimize M.toringoides extraction to yield the highest cyto-protective activity and effectively increase the yield... [more]
Simple Preparation of Diverse Neoagaro-Oligosaccharides
Fudi Lin, Jing Ye, Yayan Huang, Yucheng Yang, Meitian Xiao
July 30, 2019 (v1)
Subject: Biosystems
Keywords: agar, enzymatic hydrolysis, neoagaro-oligosaccharides, separation
A simple method for obtaining pure and well-defined oligosaccharides was established by hydrolyzing agar with β-agarase from Vibrio natriegens. The conditions for enzymolysis were optimized as follows: a temperature of 45 °C, a pH of 8.5, a substrate concentration of 0.3%, an enzyme amount of 100 U/g and an enzymolysis time of 20 h. Neoagaro-oligosaccharides with different degrees of polymerization were obtained by hydrolyzing agar with β-agarase for different lengths of time. After removing pigments using activated carbon and salts by dialyzing, the enzyme hydrolysis solution was separated with Bio-Gel P2 column chromatography. Neoagaro-oligosaccharides with different degrees of polymerization were acquired. By comparing with authentic standard substances, along with further confirmation by FTIR, MS and NMR, structures of the purified neoagaro-oligosaccharides were identified as neoagarobiose (NA2), neoagaroteraose (NA4), neoagarohexaose (NA6), neoagarooctaose (NA8), neoagaro-decaose... [more]
Extended Utilization of Constraint-Based Metabolic Model in a Long-Growing Crop
Porntip Chiewchankaset, Saowalak Kalapanulak, Treenut Saithong
July 29, 2019 (v1)
Subject: Biosystems
Keywords: biomass components, biomass function, carbon flux prediction, cassava storage root model, constraint-based modeling, long-growing crop, model sensitivity, rMeCBM model, specific storage root growth rate, specific sucrose uptake rate
The constraint-based rMeCBM-KU50 model of cassava storage root growth was analyzed to evaluate its sensitivity, with respect to reaction flux distribution and storage root growth rate, to changes in model inputted data and constraints, including sucrose uptake rate-related data—photosynthetic rate, total leaf area, total photosynthetic rate, storage root dry weight, and biomass function-related data. These mainly varied within ±90% of the model default values, although exceptions were made for the carbohydrate (−90% to 8%) and starch (−90% to 9%) contents. The results indicated that the predicted storage root growth rate was highly affected by specific sucrose uptake rates through the total photosynthetic rate and storage root dry weight variations; whereas the carbon flux distribution, direction and partitioning inclusive, was more sensitive to the variation in biomass content, particularly the carbohydrate content. This study showed that the specific sucrose uptake rate based on the... [more]
Synthesis and Characterization of Natural Extracted Precursor Date Palm Fibre-Based Activated Carbon for Aluminum Removal by RSM Optimization
Alfarooq O. Basheer, Marlia M. Hanafiah, Mohammed Abdulhakim Alsaadi, Y. Al-Douri, M.A. Malek, Mustafa Mohammed Aljumaily, Seef Saadi Fiyadh
July 28, 2019 (v1)
Subject: Biosystems
Keywords: aluminum removal, Biomass, date palm fibre, Optimization, powder-activated carbon, wastewater treatment
The Powder-Activated Carbon (PAC) under optimum conditions from a new low-cost precursor Date Palm Fibre (DPF) biomass through a carbonization followed by KOH activation has been synthesized by response surface methodology (RSM) combined with central composite design (CCD). The special effects of activation temperature, time, and impregnation ratio on bio-PAC Aluminum (Al3+) removal and uptake capacity were examined. The optimum conditions for synthesized bio-PAC were found to be 99.4% and 9.94 mg·g−1 for Al3+ removal and uptake capacity, respectively at activation temperature 650 °C, activation time 1h and impregnation ratio 1. The optimum bio-PAC was characterized and analyzed using FESEM, FTIR, XRD, TGA, BET, and Zeta potential. RSM-CCD experimental design was used to optimize removal and uptake capacity of Al3+ on bio-PAC. Optimum conditions were found to be at bio-PAC dose of 5 mg with pH 9.48 and contact time of 117 min. Furthermore, at optimized conditions of Al3+ removal, kinet... [more]
An Improvement in Biodiesel Production from Waste Cooking Oil by Applying Thought Multi-Response Surface Methodology Using Desirability Functions
Marina Corral Bobadilla, Rubén Lostado Lorza, Rubén Escribano García, Fátima Somovilla Gómez, Eliseo P. Vergara González
July 26, 2019 (v1)
Subject: Biosystems
Keywords: biodiesel, Catalysis, multi-response surface methodology, waste cooking oil
The exhaustion of natural resources has increased petroleum prices and the environmental impact of oil has stimulated the search for an alternative source of energy such as biodiesel. Waste cooking oil is a potential replacement for vegetable oils in the production of biodiesel. Biodiesel is synthesized by direct transesterification of vegetable oils, which is controlled by several inputs or process variables, including the dosage of catalyst, process temperature, mixing speed, mixing time, humidity and impurities of waste cooking oil that was studied in this case. Yield, turbidity, density, viscosity and higher heating value are considered as outputs. This paper used multi-response surface methodology (MRS) with desirability functions to find the best combination of input variables used in the transesterification reactions to improve the production of biodiesel. In this case, several biodiesel optimization scenarios have been proposed. They are based on a desire to improve the biodies... [more]
Investigation of Ethanol Production Potential from Lignocellulosic Material without Enzymatic Hydrolysis Using the Ultrasound Technique
Manoj Kandasamy, Ihsan Hamawand, Leslie Bowtell, Saman Seneweera, Sayan Chakrabarty, Talal Yusaf, Zaidoon Shakoor, Sattar Algayyim, Friederike Eberhard
July 26, 2019 (v1)
Subject: Biosystems
Keywords: bagasse, bioethanol, biofuel, Biomass, lignocellulose, pre-treatment
This research investigates ethanol production from waste lignocellulosic material (sugarcane bagasse). The bagasse was first pretreated using chemicals and ultrasound techniques. These pretreatment techniques were applied separately and combined. The pretreated bagasse was then fermented anaerobically for biofuel production without enzymatic hydrolysis. The results showed higher ethanol production than those reported in the literature. The maximum ethanol production of 820 mg/L was achieved with a combination of ultrasound (60 amplitude level, 127 W) and acid (3% H₂SO₄ concentration). The combination of two-step pretreatment such as an ultrasound (50 amplitude level, 109 W) with acid (3% H₂SO₄ concentration) and then an ultrasound with alkaline (23% NaOH concentration) generated 911 mg/L of ethanol.
Strategic Framework for Parameterization of Cell Culture Models
Pavlos Kotidis, Cleo Kontoravdi
July 25, 2019 (v1)
Subject: Biosystems
Keywords: cell culture modeling, Chinese hamster ovary cells, global sensitivity analysis, model validation, parameter estimation
Global Sensitivity Analysis (GSA) is a technique that numerically evaluates the significance of model parameters with the aim of reducing the number of parameters that need to be estimated accurately from experimental data. In the work presented herein, we explore different methods and criteria in the sensitivity analysis of a recently developed mathematical model to describe Chinese hamster ovary (CHO) cell metabolism in order to establish a strategic, transferable framework for parameterizing mechanistic cell culture models. For that reason, several types of GSA employing different sampling methods (Sobol’, Pseudo-random and Scrambled-Sobol’), parameter deviations (10%, 30% and 50%) and sensitivity index significance thresholds (0.05, 0.1 and 0.2) were examined. The results were evaluated according to the goodness of fit between the simulation results and experimental data from fed-batch CHO cell cultures. Then, the predictive capability of the model was tested against four different... [more]
Novel Deep Eutectic Solvent Based on Levulinic Acid and 1,4-Butanediol as an Extraction Media for Bioactive Alkaloid Rutaecarpine
Yue-Yue Si, Shi-Wei Sun, Kun Liu, Yang Liu, Hai-Lin Shi, Ke Zhao, Jin Wang, Wei Wang
July 25, 2019 (v1)
Subject: Biosystems
Keywords: deep eutectic solvents, indolopyridoquinazolinone alkaloid, rutaecarpin, Tetradium ruticarpum, Wuji Pill, Zuojin Pill
Deep eutectic solvents (DESs) are increasingly receiving interest as a new type of green and sustainable alternative to hazardous organic solvents. In this work, a novel DES based on levulinic acid (La) and 1,4-butanediol (Buta) as an extraction media was developed for extracting the bioactive alkaloid rutaecarpine from the unripe fruits of Tetradium ruticarpum. 24 different DESs consisting of choline chloride, betaine, sugar alcohols, organic acids, amides, and sugars were prepared and tailored to test their extraction efficiency. After initial screening, a hydrophilic DES composed of La and Buta with 1:0.5 molar ratio containing 25% water was tailored for the highest extraction efficiency, followed by the optimizations of molar ratio and water content. The interaction between the molecules of La-Buta DES was investigated by nuclear magnetic resonance spectroscopy in order to confirm its deep eutectic supermolecular structure feature. The extraction conditions were optimized by single... [more]
Accelerating Biologics Manufacturing by Upstream Process Modelling
Martin Kornecki, Jochen Strube
July 25, 2019 (v1)
Subject: Biosystems
Keywords: biologics, manufacturing, Modelling, Monod kinetics, Process Intensification, upstream processing
Intensified and accelerated development processes are being demanded by the market, as innovative biopharmaceuticals such as virus-like particles, exosomes, cell and gene therapy, as well as recombinant proteins and peptides will possess no available platform approach. Therefore, methods that are able to accelerate this development are preferred. Especially, physicochemical rigorous process models, based on all relevant effects of fluid dynamics, phase equilibrium, and mass transfer, can be predictive, if the model is verified and distinctly quantitatively validated. In this approach, a macroscopic kinetic model based on Monod kinetics for mammalian cell cultivation is developed and verified according to a general valid model validation workflow. The macroscopic model is verified and validated on the basis of four decision criteria (plausibility, sensitivity, accuracy and precision as well as equality). The process model workflow is subjected to a case study, comprising a Chinese hamst... [more]
Development of Environmental Friendly Dust Suppressant Based on the Modification of Soybean Protein Isolate
Hu Jin, Wen Nie, Yansong Zhang, Hongkun Wang, Haihan Zhang, Qiu Bao, Jiayi Yan
July 25, 2019 (v1)
Subject: Biosystems
Keywords: analysis of dust suppression mechanism, dust suppressant, optimal concentration, performance characterization, soybean protein isolate modification
Aiming to further improve the dust suppression performance of the dust suppressant, the present study independently develops a new type of biodegradable environmentally-friendly dust suppressant. Specifically, the naturally occurring biodegradable soybean protein isolate (SPI) is selected as the main material, which is subject to an anionic surfactant, i.e., sodium dodecyl sulfonate (SDS) for modification with the presence of additives including carboxymethylcellulose sodium and methanesiliconic acid sodium. As a result, the SDS-SPI cementing dust suppressant is produced. The present study experimentally tests solutions with eight different dust suppressant concentrations under the same experimental condition, so as to evaluate their dust suppression performances. Key metrics considered include water retention capability, cementing power and dust suppression efficiency. The optimal concentration of dust suppressant solution is determined by collectively comparing these metrics. The exp... [more]
Synthesis of Porous Fe/C Bio-Char Adsorbent for Rhodamine B from Waste Wood: Characterization, Kinetics and Thermodynamics
Yao Zhang, Zhichao Lou, Chaochao Wang, Weikai Wang, Jiabin Cai
July 25, 2019 (v1)
Subject: Biosystems
Keywords: Adsorption, bio-char, Fe3C, kinetics, magnetic
In the past decades, dyes waste waters produced from industries have become a major source of environmental pollution causing the destruction of aquatic communities in the ecosystem and greatly threatened human health. Herein, a novel magnetic adsorbent was synthesized by carbonizing iron (III) 2,4-pentanedionate (Fe(acac)3) pre-enriched forestry waste wood at a pyrolysis temperature of 1000 °C. The characterization of the adsorbent conducted via SEM, EDS, VSM, XRD, XPS, and FT-IR spectroscopy. The adsorption trend followed the pseudo-second order kinetics model. The corresponding adsorption performance was efficient with an equilibrium time of only 1 min. Affect factors on the adsorption performance, such as adsorbent dosage, contact time and temperature, were investigated. The magnetic bio-char showed a high adsorption capacity and an efficient adsorption toward RhB, implying great potential application in the treatment of colored wastewaters.
Study on Mass Transfer Kinetics of Sugar Extraction from Sweet Sorghum Biomass via Diffusion Process and Ethanol Yield Using SSF
Nana Baah Appiah-Nkansah, Jun Li, Ke Zhang, Meng Zhang, Donghai Wang
July 17, 2019 (v1)
Subject: Biosystems
Keywords: bioethanol, diffusion, ethanol fermentation, kinetic model, mass transfer, sweet sorghum juice
Sweet sorghum juice, a potential bioethanol feedstock, can be incorporated into the dry-grind ethanol process to improve sugar utilization efficiency, thereby enhancing ethanol yields. The juice is normally obtained by pressing the stalk through roller mills in tandem. Juice extraction by this process is known to be labor intensive, less efficient, and susceptible to considerable fermentable sugar loss due to microbial activities when stored at room temperature. Sweet sorghum juice extraction via diffusion has recently been proposed to improve sugar recovery efficiency. In this study, extraction kinetics based on the optimized diffusion parameters (8% grain loading, 85 °C, and 120 min) were determined to describe the mass transfer of sugars in sweet sorghum biomass during the diffusion process. Diffusion parameters obtained from previous studies were used to extract free sugars and convert them into ethanol using granular starch hydrolyzing enzymes (GSHE) and traditional enzymes. Ethan... [more]
A Glucose-Dependent Pharmacokinetic/ Pharmacodynamic Model of ACE Inhibition in Kidney Cells
Minu R. Pilvankar, Hui Ling Yong, Ashlee N. Ford Versypt
July 11, 2019 (v1)
Subject: Biosystems
Keywords: benazepril, diabetic kidney disease, diabetic nephropathy, PK/PD, podocytes, renin-angiotensin system
Diabetic kidney disease (DKD) is a major cause of renal failure. Podocytes are terminally differentiated renal epithelial cells that are key targets of damage due to DKD. Podocytes express a glucose-stimulated local renin-angiotensin system (RAS) that produces angiotensin II (ANG II). Local RAS differs from systemic RAS, which has been studied widely. Hyperglycemia increases the production of ANG II by podocyte cells, leading to podocyte injury. Angiotensin-converting enzyme (ACE) is involved in the production of ANG II, and ACE inhibitors are drugs used to suppress elevated ANG II concentration. As systemic RAS differs from the local RAS in podocytes, ACE inhibitor drugs should act differently in local versus systemic contexts. Experimental and computational studies have considered the pharmacokinetics (PK) and pharmacodynamics (PD) of ACE inhibition of the systemic RAS. Here, a PK/PD model for ACE inhibition is developed for the local RAS in podocytes. The model takes constant or dyn... [more]
High Nitrate and Phosphate Ions Reduction in Modified Low Salinity Fresh Water through Microalgae Cultivation
Ahmad Rozaimee Mustaffa, Ku Halim Ku Hamid, Mohibah Musa, Juferi Idris, Roslina Ramli
July 11, 2019 (v1)
Subject: Biosystems
Keywords: biodiesel, Carbon Dioxide, fresh water, low salinity, nitrate ions, phosphate ions, Spirogyra sp., Tetraspora sp.
The treatment of nitrate and phosphate ions in fresh water such as streams, rivers, lakes, reservoirs, and wetlands through biological treatment has been getting more crucial and popular in recent years. This paper reports the reduction of nitrate and phosphate ions in modified low salinity fresh water via the cultivation of a microalgae strain, e.g., Tetraspora sp. and Spirogyra sp. The low salinity fresh water (9054 to 9992 ppm) was modified with the addition of organic fertiliser (VermiCompost Tea) and used as the cultivation medium to grow microalgae. The microalgae strains were grown under controlled conditions in an indoor laboratory for 14 days. The initial concentrations of nitrate and phosphate ions in the modified fresh water sample were 1.17 mg/L and 0.10 mg/L, respectively. The reduction of nitrate and phosphate ions associated with the effect of cultivation of Tetraspora sp. and Spirogyra sp. in ambient air (0.03% of CO2) and 15% of CO2 was investigated. In ambient air, th... [more]
Effect of the Freeze-Drying Process on the Physicochemical and Microbiological Properties of Mexican Kefir Grains
Alicia Águeda Conde-Islas, Maribel Jiménez-Fernández, Denis Cantú-Lozano, Galo Rafael Urrea-García, Guadalupe Luna-Solano
July 11, 2019 (v1)
Subject: Biosystems
Keywords: freeze-drying, kefir grains, operating parameters, probiotic, properties
The purpose of this study was to investigate how the properties of Mexican kefir grains (MKG) are affected by the operating parameters used in the freeze-drying process. The factors investigated were the freezing time (3−9 h), freezing temperature (−20 to −80 °C), pressure (0.2−0.8 mbar), and lyophilization time (5−20 h). The maximum range of change and one-way analysis of variance showed that lyophilization time and freezing time significant affects (p < 0.05) the response variables, residual moisture content and water activity, and pressure had a significant effect on the color difference and survival rate of probiotic microorganisms. The best drying conditions were a freezing time of 3 h, a freezing temperature of −20 °C, a pressure of 0.6 mbar, and a lyophilization time of 15 h. Under these conditions, we obtained a product with residual moisture content below 6%, water activity below 0.2, and survival rates above 8.5 log cfu per gram of lactic acid bacteria and above 8.6 log fo... [more]
Water−Organic Solvent Extraction of Phenolic Antioxidants from Brewers’ Spent Grain
Antonio Zuorro, Annalaura Iannone, Roberto Lavecchia
July 11, 2019 (v1)
Subject: Biosystems
Keywords: brewers’ spent grain, phenolic compounds, solvent extraction, waste valorization
Brewers’ spent grain (BSG) is the most abundant by-product of the brewing process. BSG is currently disposed of or used as a supplement for animal feed, although it contains significant amounts of bioactive compounds of great interest to the pharmaceutical, cosmetic and food sectors. In this study we investigate the feasibility of using a simple solvent extraction procedure to recover phenolic antioxidants from BSG. Acetone−water and ethanol−water mixtures were used as extraction solvents. Phenolic extracts obtained by treatment of BSG with the two solvent systems were characterized in terms of total phenolics and antioxidant activity. For both systems, the extraction yield was maximum at 60% (v/v) organic solvent concentration. At all solvent compositions, mixtures containing acetone provided higher extraction yields. As suggested by the strong correlation between the antioxidant activity of BSG extracts and their phenolic content, the antioxidant capacity of the extracts can be mainl... [more]
Effects of Caustic Extraction on Properties of Viscose Grade Dissolving Pulp
Cindy Friebel, Robert H. Bischof, Gabriele Schild, Karin Fackler, Ireen Gebauer
July 5, 2019 (v1)
Subject: Biosystems
Keywords: caustic extraction, cellulosic fibres, dissolving pulp, pulp, textile fibres, viscose, wood
Viscose, a cellulose-based commodity fibre, is produced by pulping and bleaching of wood, yielding a high quality “dissolving pulp” which is then spun. During pulping and bleaching, effective hemicellulose extraction is required to allow fibre production. We present a design of experiments (DoE) approach to optimise caustic extraction in a total chlorine free (TCF) bleaching sequence (O-CE-Z-P) of beech wood sulphite pulp. Temperature and sodium hydroxide concentration were varied to identify highest xylan extraction yield, and a maximum xylan removal of 83% was achieved at 20 °C and 120 g/L NaOH. Additionally, caustic extraction conditions were derived from the DoE model that led to pulps with high yield, high alpha cellulose content or uniform cellulose molecular weight distribution. Pulps from verification experiments exhibited good reactivity in viscose application tests. Hence, the presented O-CE-Z-P bleaching sequence can be considered as suitable for integrated viscose fibre pro... [more]
Mechanistic Models of Inducible Synthetic Circuits for Joint Description of DNA Copy Number, Regulatory Protein Level, and Cell Load
Lorenzo Pasotti, Massimo Bellato, Davide De Marchi, Paolo Magni
July 5, 2019 (v1)
Subject: Biosystems
Keywords: bottom-up design, cell load, copy number, inducible promoter, mathematical modeling, mechanistic model, synthetic biology
Accurate predictive mathematical models are urgently needed in synthetic biology to support the bottom-up design of complex biological systems, minimizing trial-and-error approaches. The majority of models used so far adopt empirical Hill functions to describe activation and repression in exogenously-controlled inducible promoter systems. However, such equations may be poorly predictive in practical situations that are typical in bottom-up design, including changes in promoter copy number, regulatory protein level, and cell load. In this work, we derived novel mechanistic steady-state models of the lux inducible system, used as case study, relying on different assumptions on regulatory protein (LuxR) and cognate promoter (Plux) concentrations, inducer-protein complex formation, and resource usage limitation. We demonstrated that a change in the considered model assumptions can significantly affect circuit output, and preliminary experimental data are in accordance with the simulated ac... [more]
Biomaterial Implants in Abdominal Wall Hernia Repair: A Review on the Importance of the Peritoneal Interface
Verónica Gómez-Gil, Gemma Pascual, Juan M. Bellón
June 10, 2019 (v1)
Subject: Biosystems
Keywords: abdominal wall, hernia recurrence, hernia repair, omentum, peritoneal adhesions, peritoneum, polypropylene, surgical mesh
Biomaterials have long been used to repair defects in the clinical setting, which has led to the development of a wide variety of new materials tailored to specific therapeutic purposes. The efficiency in the repair of the defect and the safety of the different materials employed are determined not only by the nature and structure of their components, but also by the anatomical site where they will be located. Biomaterial implantation into the abdominal cavity in the form of a surgical mesh, such as in the case of abdominal hernia repair, involves the contact between the foreign material and the peritoneum. This review summarizes the different biomaterials currently available in hernia mesh repair and provides insights into a series of peculiarities that must be addressed when designing the optimal mesh to be used in this interface.
Accelerating Biologics Manufacturing by Modeling or: Is Approval under the QbD and PAT Approaches Demanded by Authorities Acceptable without a Digital-Twin?
Steffen Zobel-Roos, Axel Schmidt, Fabian Mestmäcker, Mourad Mouellef, Maximilian Huter, Lukas Uhlenbrock, Martin Kornecki, Lara Lohmann, Reinhard Ditz, Jochen Strube
June 10, 2019 (v1)
Subject: Biosystems
Keywords: biologics, continuous bioprocessing, manufacturing, Modelling, modular plants, Process Intensification, Renewable and Sustainable Energy
Innovative biologics, including cell therapeutics, virus-like particles, exosomes, recombinant proteins, and peptides, seem likely to substitute monoclonal antibodies as the main therapeutic entities in manufacturing over the next decades. This molecular variety causes a growing need for a general change of methods as well as mindset in the process development stage, as there are no platform processes available such as those for monoclonal antibodies. Moreover, market competitiveness demands hyper-intensified processes, including accelerated decisions toward batch or continuous operation of dedicated modular plant concepts. This indicates gaps in process comprehension, when operation windows need to be run at the edges of optimization. In this editorial, the authors review and assess potential methods and begin discussing possible solutions throughout the workflow, from process development through piloting to manufacturing operation from their point of view and experience. Especially,... [more]
Relationship Between MiRKAT and Coefficient of Determination in Similarity Matrix Regression
Xiang Zhan
June 8, 2019 (v1)
Subject: Biosystems
Keywords: coefficient of determination R2, fraction of variance explained, microbiome association analysis, MiRKAT, similarity matrix regression
The Microbiome Regression-based Kernel Association Test (MiRKAT) is widely used in testing for the association between microbiome compositions and an outcome of interest. The MiRKAT statistic is derived as a variance-component score test in a kernel machine regression-based generalized linear mixed model. In this brief report, we show that the MiRKAT statistic is proportional to the R 2 (coefficient of determination) statistic in a similarity matrix regression, which characterizes the fraction of variability in outcome similarity, explained by microbiome similarity (up to a constant).
Comparison of Three Deoxidation Agents for Ozonated Broths Used in Anaerobic Biotechnological Processes
Ewelina Pawlikowska, Jaroslaw Domanski, Piotr Dziugan, Joanna Berlowska, Weronika Cieciura-Wloch, Krzysztof Smigielski, Dorota Kregiel
May 16, 2019 (v1)
Subject: Biosystems
Keywords: deoxidation, iron sulfate, Metschnikowia sp., ozonation, ultrasound
Anaerobic fermentation of organic compounds is used in many biotechnological processes and has been the subject of much research. A variety of process conditions and different growth media can be used to obtain microbial metabolites. The media must be free from contamination before fermentation. Sterilization is most often achieved by applying heat or other treatments, such as ozonation. Sterilization of liquid media using ozone can be very beneficial, but this method introduces high concentrations of residual oxygen, which inhibit anaerobic processes. Deoxidation is therefore necessary to remove the oxygen from ozonated broths. This study evaluates the effectiveness of three deoxidation agents for two kinds of fermentation media based on malt or molasses: ultrasound, iron(II) sulfate, and Metschnikowia sp. yeast. The time needed for deoxidation varied, depending on the kind of broth and the deoxidation agent. In general, the dynamics of oxygen removal were faster in malt broth. A comp... [more]
Integrated Hydrolysis of Mixed Agro-Waste for a Second Generation Biorefinery Using Nepenthes mirabilis Pod Digestive Fluids
Nkosikho Dlangamandla, Seteno Karabo Obed Ntwampe, Justine Oma Angadam, Elie Fereche Itoba-Tombo, Boredi Silas Chidi, Lukhanyo Mekuto
May 16, 2019 (v1)
Subject: Biosystems
Keywords: agro-waste, biorefinery, carboxylesterases, cellulases, Nepenthes mirabilis, total reducing sugars, xylanase, β-glucosidase
To sustainably operate a biorefinery with a low cost input in a commercial setting, the hydrolysis of lignocellulosic biomass must be undertaken in a manner which will impart environmental tolerance while reducing fermenter inhibitors from the delignification process. The challenge lies with the highly recalcitrant lignin structure, which limits the conversion of the holocelluloses to fermentable total reducing sugars (TRS). Due to these challenges, sustainable and innovative methods to pre-treat biomass must be developed for delignocellulolytic operations. Herein, Nepenthes mirabilis digestive fluids shown to have ligninolytic, cellulolytic and xylanolytic activities were used as an enzyme cocktail to hydrolyse mixed agro-waste constituted by Citrus sinensis (orange), Malus domestica (apple) peels, cobs from Zea mays (maize) and Quercus robur (oak) yard waste. The digestive fluids contained carboxylesterases (529.41 ± 30.50 U/L), β-glucosidases (251.94 ± 11.48 U/L) and xylanases (36.0... [more]
Effect of Supercritical Fluid Extraction Process on Chemical Composition of Polianthes tuberosa Flower Extracts
Javier C. Fragoso-Jiménez, Ernesto Tapia-Campos, Mirna Estarron-Espinosa, Rodrigo Barba-Gonzalez, Ma. Claudia Castañeda-Saucedo, Gustavo A. Castillo-Herrera
May 16, 2019 (v1)
Subject: Biosystems
Keywords: chemical composition, Polianthes tuberosa, supercritical fluid extraction
Supercritical fluid extracts from flowers of Polianthes tuberosa var. double were ob tained using carbon dioxide as a solvent. Yield extract obtained was 2.5%. The effects of the pressure process (18 MPa, 28 MPa, and 38 MPa) and temperature process (313 K, 323 K, and 333 K) on the volatile composition of tuberose flowers extracts were evaluated, and a significant variation in chemical composition was found. Characteristic compounds of tuberose as methyl isoeugenol, benzyl benzoate, methyl anthranilate, pentacosene, and heptacosene were obtained mainly at 18 MPa and 333 K process conditions, and could be used in the perfume or fragrance industry. Components such as geraniol, farnesol, and methyl eugenol were also obtained, these extracts could be used in the development of cosmeceutical products. This work allowed to identification of the chemical composition profile and evaluation of the changes in tuberose extracts due to the extraction process.
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