scholarly journals Sugarcane Bagasse Hydrolysis Enhancement by Microwave-Assisted Sulfolane Pretreatment

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1703 ◽  
Author(s):  
Patricia Portero-Barahona ◽  
Enrique Javier Carvajal-Barriga ◽  
Jesús Martín-Gil ◽  
Pablo Martín-Ramos
Keyword(s):  
Reaction Time ◽  
Sugarcane Bagasse ◽  
Energy Savings ◽  
Enzymatic Saccharification ◽  
Reaction Medium ◽  
Value Added ◽  
Positive Influence ◽  
Industrial Applications ◽  
Combined Pretreatment ◽  
Total Reducing Sugars

Sugarcane bagasse is the major by-product of the sugarcane industry and, due to its abundant availability, it has been extensively studied for lignocellulosic bioconversion in the production of bioethanol and other value-added commercial products. In the study presented herein, a combined pretreatment using sulfolane, TiO2 and alkali microwave irradiation (MW-A) was assessed for the dissolution of lignin prior to enzymatic saccharification of holocellulose. Total reducing sugars (TRS) and saccharinic acid yields were investigated. The increase in NaOH concentration up to 5% and in temperature from 120 °C to 140 °C were found to have a positive influence on both yields. While increasing the reaction time from 5 to 60 min only led to an increase in TRS yield <2%, a reaction time of 30 min almost doubled the saccharinic acids production. TRS yields and saccharinic acid production were approximately 5% and 33% higher when the sulfolane-TiO2 reaction medium was used, as compared to MW-A in water, reaching up to 64.8% and 15.24 g/L of saccharinic acids, respectively. The proposed MW-A pretreatment may hold promise for industrial applications, given the good TRS yields obtained, and the associated enzyme and time/energy savings. The use of sulfolane-TiO2 reaction medium is encouraged if saccharinic acids are to be recovered too.

Pengaruh Intellectual Capital, Profitabilitas, Dan Leverage Terhadap Nilai Perusahaan Pada Perusahaan Sektor Properti, Real Estate, Dan Konstruksi Bangunan Yang Terdaftar Di Bursa Efek Indonesia

2018 ◽  
Vol 9 (2) ◽  
pp. 1-14
Author(s):  
Haryani Chandra ◽  
Hamfri Djajadikerta
Keyword(s):  
Real Estate ◽  
Intellectual Capital ◽  
Firm Value ◽  
Stock Price ◽  
Stock Exchange ◽  
Value Added ◽  
Simple Random Sampling ◽  
Positive Influence ◽  
Public Companies ◽  
Equity Ratio

Go public companies have main purpose to increase firm value consistently. Increased firm value can reflect the increase in the prosperity of shareholders. The purpose of this research is to determine whether intellectual capital, profitability, and leverage have an influence on firm value. This research is expected to help companies to determine the focus on managing the factors those have an influence towards firm value and help investors and potential investors to make investment decisions. This research is conducted on firms listed in property, real estate, and building construction sector in Indonesia Stock Exchange during 2010 until 2015. Samples are selected by simple random sampling method. The research method used is the regression analysis. Intellectual capital is measured by value added intellectual coefficient (VAIC), profitability is measured by return on assets (ROA), leverage is measured by debt- to-equity ratio (DER), and firm value is measured by the year-end closing stock price. The results showed that intellectual capital, profitability, and leverage have partially a significant positive influence on firm value. In addition, intellectual capital, profitability, and leverage have significant influence simultaneously on firm value. Keywords: firm value, intellectual capital, leverage, profitability

scholarly journals Valorization of sugarcane bagasse by chemical pretreatment and enzyme mediated deconstruction

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Vihang S. Thite ◽  
Anuradha S. Nerurkar
Keyword(s):  
Cell Wall ◽  
Sugarcane Bagasse ◽  
Structural Changes ◽  
Enzymatic Saccharification ◽  
Dry Weight ◽  
Gravimetric Analysis ◽  
Chemical Pretreatment ◽  
Cell Wall Degrading Enzymes ◽  
First Time ◽  
Soluble Components

Abstract After chemical pretreatment, improved amenability of agrowaste biomass for enzymatic saccharification needs an understanding of the effect exerted by pretreatments on biomass for enzymatic deconstruction. In present studies, NaOH, NH4OH and H2SO4 pretreatments effectively changed visible morphology imparting distinct fibrous appearance to sugarcane bagasse (SCB). Filtrate analysis after NaOH, NH4OH and H2SO4 pretreatments yielded release of soluble reducing sugars (SRS) in range of ~0.17–0.44%, ~0.38–0.75% and ~2.9–8.4% respectively. Gravimetric analysis of pretreated SCB (PSCB) biomass also revealed dry weight loss in range of ~25.8–44.8%, ~11.1–16.0% and ~28.3–38.0% by the three pretreatments in the same order. Release of soluble components other than SRS, majorly reported to be soluble lignins, were observed highest for NaOH followed by H2SO4 and NH4OH pretreatments. Decrease or absence of peaks attributed to lignin and loosened fibrous appearance of biomass during FTIR and SEM studies respectively further corroborated with our observations of lignin removal. Application of commercial cellulase increased raw SCB saccharification from 1.93% to 38.84%, 25.56% and 9.61% after NaOH, H2SO4 and NH4OH pretreatments. Structural changes brought by cell wall degrading enzymes were first time shown visually confirming the cell wall disintegration under brightfield, darkfield and fluorescence microscopy. The microscopic evidence and saccharification results proved that the chemical treatment valorized the SCB by making it amenable for enzymatic saccharification.

scholarly journals Extraction of sugarcane bagasse arabinoxylan, integrated with enzymatic production of xylo-oligosaccharides and separation of cellulose

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Leila Khaleghipour ◽  
Javier A. Linares-Pastén ◽  
Hamid Rashedi ◽  
Seyed Omid Ranaei Siadat ◽  
Andrius Jasilionis ◽  
...  
Keyword(s):  
Sugarcane Bagasse ◽  
Sugar Content ◽  
Value Added ◽  
Apparent Molecular Weight ◽  
Bacillus Halodurans ◽  
Glycoside Hydrolase Family ◽  
High Concentration ◽  
Enzymatic Production ◽  
Successful Separation ◽  
Ft Ir

AbstractSugarcane processing roughly generates 54 million tonnes sugarcane bagasse (SCB)/year, making SCB an important material for upgrading to value-added molecules. In this study, an integrated scheme was developed for separating xylan, lignin and cellulose, followed by production of xylo-oligosaccharides (XOS) from SCB. Xylan extraction conditions were screened in: (1) single extractions in NaOH (0.25, 0.5, or 1 M), 121 °C (1 bar), 30 and 60 min; (2) 3 × repeated extraction cycles in NaOH (1 or 2 M), 121 °C (1 bar), 30 and 60 min or (3) pressurized liquid extractions (PLE), 100 bar, at low alkalinity (0–0.1 M NaOH) in the time and temperature range 10–30 min and 50–150 °C. Higher concentration of alkali (2 M NaOH) increased the xylan yield and resulted in higher apparent molecular weight of the xylan polymer (212 kDa using 1 and 2 M NaOH, vs 47 kDa using 0.5 M NaOH), but decreased the substituent sugar content. Repeated extraction at 2 M NaOH, 121 °C, 60 min solubilized both xylan (85.6% of the SCB xylan), and lignin (84.1% of the lignin), and left cellulose of high purity (95.8%) in the residuals. Solubilized xylan was separated from lignin by precipitation, and a polymer with β-1,4-linked xylose backbone substituted by arabinose and glucuronic acids was confirmed by FT-IR and monosaccharide analysis. XOS yield in subsequent hydrolysis by endo-xylanases (from glycoside hydrolase family 10 or 11) was dependent on extraction conditions, and was highest using xylan extracted by 0.5 M NaOH, (42.3%, using Xyn10A from Bacillus halodurans), with xylobiose and xylotriose as main products. The present study shows successful separation of SCB xylan, lignin, and cellulose. High concentration of alkali, resulted in xylan with lower degree of substitution (especially reduced arabinosylation), while high pressure (using PLE), released more lignin than xylan. Enzymatic hydrolysis was more efficient using xylan extracted at lower alkaline strength and less efficient using xylan obtained by PLE and 2 M NaOH, which may be a consequence of polymer aggregation, via remaining lignin interactions.

scholarly journals Effects of a Twin-Screw Extruder Equipped with a Molten Resin Reservoir on the Mechanical Properties and Microstructure of Recycled Waste Plastic Polyethylene Pellet Moldings

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1058
Author(s):  
Hikaru Okubo ◽  
Haruka Kaneyasu ◽  
Tetsuya Kimura ◽  
Patchiya Phanthong ◽  
Shigeru Yao
Keyword(s):  
Mechanical Properties ◽  
Mechanical Performance ◽  
Value Added ◽  
Industrial Applications ◽  
Twin Screw Extruder ◽  
Screw Extruder ◽  
Polymer Properties ◽  
Wide Range ◽  
Twin Screw ◽  
Recycled Plastics

Each year, increasing amounts of plastic waste are generated, causing environmental pollution and resource loss. Recycling is a solution, but recycled plastics often have inferior mechanical properties to virgin plastics. However, studies have shown that holding polymers in the melt state before extrusion can restore the mechanical properties; thus, we propose a twin-screw extruder with a molten resin reservoir (MSR), a cavity between the screw zone and twin-screw extruder discharge, which retains molten polymer after mixing in the twin-screw zone, thus influencing the polymer properties. Re-extruded recycled polyethylene (RPE) pellets were produced, and the tensile properties and microstructure of virgin polyethylene (PE), unextruded RPE, and re-extruded RPE moldings prepared with and without the MSR were evaluated. Crucially, the elongation at break of the MSR-extruded RPE molding was seven times higher than that of the original RPE molding, and the Young’s modulus of the MSR-extruded RPE molding was comparable to that of the virgin PE molding. Both the MSR-extruded RPE and virgin PE moldings contained similar striped lamellae. Thus, MSR re-extrusion improved the mechanical performance of recycled polymers by optimizing the microstructure. The use of MSRs will facilitate the reuse of waste plastics as value-added materials having a wide range of industrial applications.

scholarly journals Optimization of Synthetic Media Composition for Kluyveromyces marxianus Fed-Batch Cultivation

Fermentation ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 62
Author(s):  
Konstantins Dubencovs ◽  
Janis Liepins ◽  
Arturs Suleiko ◽  
Anastasija Suleiko ◽  
Reinis Vangravs ◽  
...  
Keyword(s):  
Kluyveromyces Marxianus ◽  
Reaction Medium ◽  
Value Added ◽  
Batch Cultivation ◽  
Batch Processes ◽  
Biomass Growth ◽  
High Cell ◽  
Media Composition ◽  
Fed Batch ◽  
Fed Batch Cultivation

The Kluyveromyces marxianus yeast recently has gained considerable attention due to its applicability in high-value-added product manufacturing. In order to intensify the biosynthesis rate of a target product, reaching high biomass concentrations in the reaction medium is mandatory. Fed-batch processes are an attractive and efficient way how to achieve high cell densities. However, depending on the physiology of the particular microbial strain, an optimal media composition should be used to avoid by-product synthesis and, subsequently, a decrease in overall process effi-ciency. Thus, the aim of the present study was to optimise the synthetic growth medium and feeding solution compositions (in terms of carbon, nitrogen, phosphorous, magnesium, and calcium concentrations) for high cell density K. marxianus fed‑batch cultivations. Additionally, the biomass yields from the vitamin mixture and other macro/microelements were identified. A model predictive control algorithm was successfully applied for a fed-batch cultivation control. Biomass growth and substrate consumption kinetics were compared with the mathematical model predictions. Finally, 2‑phenylethanol biosynthesis was induced and its productivity was estimated. The determined optimal macronutrient ratio for K. marxianus biomass growth was identified as C:N:P = 1:0.07:0.011. The maximal attained yeast biomass concentration was close to 70 g·L-1 and the 2-PE biosynthesis rate was 0.372 g·L−1·h−1, with a yield of 74% from 2-phenylalanine.

scholarly journals The Influence of R&D Intensity on Financial Performance: The Mediating Role of Human Capital in the Semiconductor Industry in Taiwan

2020 ◽  
Vol 12 (12) ◽  
pp. 5128
Author(s):  
Tsung-Chun Chen ◽  
Yenchun Jim Wu
Keyword(s):  
Human Capital ◽  
Financial Performance ◽  
Capital Investment ◽  
Performance Metrics ◽  
Intangible Assets ◽  
Semiconductor Industry ◽  
Value Added ◽  
Positive Influence ◽  
High Tech ◽  
The Relationship

Knowledge transfer is a strategy used by high-tech companies to acquire new knowledge and skills. Knowledge can be internally generated or externally sourced. The access to external knowledge is a quick fix, but the risks associated with reliance on external sources are often overlooked. However, not acquiring such knowledge is even riskier. There have been a slew of litigations in the semiconductor industry in recent years. The acquisition and assurance of intangible assets is an important issue. This paper posits that internal R&D should take into consideration the knowledge intensity and capital investment in the industry. This study focuses on the relationship between intangible assets and financial performance. It sourced the 2004 to 2016 financial data of semiconductor companies in Taiwan for panel data modeling and examined case studies for empirical validation. This study found that the higher the R&D intensity (RDI) in the value-added component of human capital, the better the financial performance of the company. RDI has a positive influence on the accumulation of human capital and financial performance metrics, and such influence is deferred. Meanwhile, human capital is a mediating factor in the relationship between RDI and financial performance. RDI is integral to the semiconductor industry’s pursuit of business sustainability.

scholarly journals The utilization of the mesoporous Ti-SBA-15 catalyst in the epoxidation of allyl alcohol to glycidol and diglycidyl ether in the water medium

2015 ◽  
Vol 17 (4) ◽  
pp. 23-31 ◽  
Author(s):  
Agnieszka Wróblewska ◽  
Edyta Makuch ◽  
Małgorzata Dzięcioł ◽  
Roman Jędrzejewski ◽  
Paweł Kochmański ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Reaction Time ◽  
Allyl Alcohol ◽  
Water Solution ◽  
Reaction Medium ◽  
Diglycidyl Ether ◽  
Molar Ratio ◽  
Water Medium ◽  
Catalyst Content ◽  
Allyl Alcohol Epoxidation

Abstract This work presents the studies on the optimization the process of allyl alcohol epoxidation over the Ti-SBA-15 catalyst. The optimization was carried out in an aqueous medium, wherein water was introduced into the reaction medium with an oxidizing agent (30 wt% aqueous solution of hydrogen peroxide) and it was formed in the reaction medium during the processes. The main investigated technological parameters were: the temperature, the molar ratio of allyl alcohol/hydrogen peroxide, the catalyst content and the reaction time. The main functions the process were: the selectivity of transformation to glycidol in relation to allyl alcohol consumed, the selectivity of transformation to diglycidyl ether in relation to allyl alcohol consumed, the conversion of allyl alcohol and the selectivity of transformation to organic compounds in relation to hydrogen peroxide consumed. The analysis of the layer drawings showed that in water solution it is best to conduct allyl alcohol epoxidation in direction of glycidol (selectivity of glycidol 54 mol%) at: the temperature of 10–17°C, the molar ratio of reactants 0.5–1.9, the catalyst content 2.9–4.0 wt%, the reaction time 2.7–3.0 h and in direction of diglycidyl ether (selectivity of diglycidyl ether 16 mol%) at: the temperature of 18–33°C, the molar ratio of reactants 0.9–1.65, the catalyst content 2.0–3.4 wt%, the reaction time 1.7–2.6 h. The presented method allows to obtain two very valuable intermediates for the organic industry.

scholarly journals Catalytic valorization of hardwood for enhanced xylose-hydrolysate recovery and cellulose enzymatic efficiency via synergistic effect of Fe3+ and acetic acid

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Kaixuan Huang ◽  
Lalitendu Das ◽  
Jianming Guo ◽  
Yong Xu
Keyword(s):  
Acetic Acid ◽  
Synergistic Effect ◽  
Paper Industry ◽  
Enzymatic Saccharification ◽  
Value Added ◽  
Lewis Acid Site ◽  
Aqueous Acetic Acid ◽  
Xylan Degradation ◽  
Hydrolysis Process ◽  
Xylonic Acid

Abstract Background Poplars are considered suitable dedicated energy crops, with abundant cellulose and hemicellulose, and huge surplus biomass potential in China. Xylan, the major hemicellulosic component, contributes to the structural stability of wood and represents a tremendous quantity of biobased chemicals for fuel production. Monomeric xylose conversion to value-added chemicals such as furfural, xylitol, and xylonic acid could greatly improve the economics of pulp-paper industry and biorefinery. Acetic acid (HAc) is used as a friendly and recyclable selective catalyst amenable to xylan degradation and xylooligosaccharides production from lignocellulosic materials. However, HAc catalyst usually works much feebly at inert woods than agricultural straws. In this study, effects of different iron species in HAc media on poplar xylan degradation were systematically compared, and a preferable Fe3+-assisted HAc hydrolysis process was proposed for comparable xylose-hydrolysate recovery (XHR) and enzymatic saccharification of cellulose. Results In presence of 6.5% HAc with 0.17–0.25 wt% Fe3+, xylose yield ranged between 72.5 and 73.9%. Additionally, pretreatment was effective in poplar delignification, with a lignin yield falling between 38.6 and 42.5%. Under similar conditions, saccharification efficiency varied between 60.3 and 65.9%. Starting with 100 g poplar biomass, a total amount of 12.7–12.8 g of xylose and 18.8–22.8 g of glucose were harvested from liquid streams during the whole process of Fe3+-HAc hydrolysis coupled with enzymatic saccharification. Furthermore, the enhancement mechanism of Fe3+ coupled with HAc was investigated after proof-of-concept experiments. Beechwood xylan and xylose were treated under the same condition as poplar sawdust fractionation, giving understanding of the effect of catalysts on the hydrolysis pathway from wood xylan to xylose and furfural by Fe3+-HAc. Conclusions The Fe3+-assisted HAc hydrolysis process was demonstrated as an effective approach to the wood xylose and other monosaccharides production. Synergistic effect of Lewis acid site and aqueous acetic acid provided a promising strategy for catalytic valorization of poplar biomass.

scholarly journals One-Pot Ionic Liquid-Mediated Bioprocess for Pretreatment and Enzymatic Hydrolysis of Rice Straw with Ionic Liquid-Tolerance Bacterial Cellulase

2022 ◽  
Vol 9 (1) ◽  
pp. 17
Author(s):  
Malinee Sriariyanun ◽  
Nichaphat Kitiborwornkul ◽  
Prapakorn Tantayotai ◽  
Kittipong Rattanaporn ◽  
Pau-Loke Show
Keyword(s):  
Ionic Liquid ◽  
Saline Soil ◽  
Enzymatic Saccharification ◽  
Value Added ◽  
Specific Enzyme ◽  
One Pot ◽  
The One ◽  
Hydrolysis Of ◽  
Bacterial Cellulase ◽  
Value Added Products

Ionic liquid (IL) pretreatment of lignocellulose is an efficient method for the enhancement of enzymatic saccharification. However, the remaining residues of ILs deactivate cellulase, therefore making intensive biomass washing after pretreatment necessary. This study aimed to develop the one-pot process combining IL pretreatment and enzymatic saccharification by using low-toxic choline acetate ([Ch][OAc]) and IL-tolerant bacterial cellulases. Crude cellulases produced from saline soil inhabited Bacillus sp. CBD2 and Brevibacillus sp. CBD3 were tested under the influence of 0.5–2.0 M [Ch][OAc], which showed that their activities retained at more than 95%. However, [Ch][OAc] had toxicity to CBD2 and CBD3 cultures, in which only 32.85% and 12.88% were alive at 0.5 M [Ch][OAc]. Based on the specific enzyme activities, the sugar amounts produced from one-pot processes using 1 mg of CBD2 and CBD3 were higher than that of Celluclast 1.5 L by 2.0 and 4.5 times, respectively, suggesting their potential for further application in the biorefining process of value-added products.

scholarly journals Optimization of Metal Ions in Sugarcane Bagasse Fermenting Medium for the Production of Streptokinase by Streptococcus equisimilis

2021 ◽  
Vol 9 (2) ◽  
pp. 24-30
Keyword(s):  
Metal Ions ◽  
Sugarcane Bagasse ◽  
Specific Activity ◽  
Gel Filtration ◽  
Value Added ◽  
Cost Effective ◽  
Fermentation Medium ◽  
Exchange Chromatography ◽  
Sds Page ◽  
The Cost

Streptokinase is a fibrinolytic enzyme and a product of β-hemolytic Streptococci strains. This enzyme is used as a medication to break down clots in some cases of heart disease. Streptococcus equisimilis, a species of group C Streptococci, is widely used for the production of streptokinase by fermentation technology. In this study, the sugarcane bagasse fermentation medium was optimized for metal ions (KH2PO4, MgSO4.7H2O, CaCO3 and NaHCO3) at various levels to attain the maximal production of streptokinase. Sugarcane bagasse was used due to its profuse availability and as an ideal substrate for microbial processes for the manufacturing of value-added products. The results showed that maximal streptokinase production was found at 0.04% KH2PO4, 0.04% MgSO4.7H2O, 0.15% NaHCO3 and 0.04% CaCO3. Finally, the optimized medium resulted in 84.75 U/mg specific activity and 74.5% recovery. The purification process was carried out simultaneously using ammonium sulfate precipitation, ion-exchange chromatography, and gel filtration. Finally, a purified sample of streptokinase was run on SDS-PAGE and resolute 47 kDa molecular weight. The use of β-hemolytic Streptococci to obtain streptokinase is not free from health risks and is related to anaphylaxis. This study provides a way forward for the cost-effective ways to obtain streptokinase for the treatment of thrombosis.

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