scholarly journals Production of Carbohydrates from Cardoon Pre-Treated by Acid-Catalyzed Steam Explosion and Enzymatic Hydrolysis

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4288 ◽  
Author(s):  
Alessandro Bertini ◽  
Mattia Gelosia ◽  
Gianluca Cavalaglio ◽  
Marco Barbanera ◽  
Tommaso Giannoni ◽  
...  

Cardoon (Cynara cardunculus) is a promising crop from which to obtain oilseeds and lignocellulosic biomass. Acid-catalyzed steam explosion is a thermochemical process that can efficiently pre-treat lignocellulosic biomass. The drawback is the production of a high number of carbohydrate degradation products in the liquid fraction that could inhibit microbial growth. In this work, the lignocellulosic biomass of cardoon, gathered from a dedicated field, were used as the raw material for the production of fermentable monosaccharides by employing acid-catalyzed steam explosion. The raw material was pre-soaked with a dilute 1% (w/w) sulfuric acid solution and then subjected to steam explosion under three different severity conditions. The recovered slurry was separated into solid and liquid fractions, which were individually characterized to determine total carbohydrate and inhibitor concentrations. The slurry and the washed solid fraction underwent enzymatic hydrolysis to release glucose and pentose monosaccharides. By conducting the pre-treatment at 175 °C for 35 min and hydrolyzing the obtained slurry, a yield of 33.17 g of monosaccharides/100 g of cardoon was achieved. At the same conditions, 4.39 g of inhibitors/100 g of cardoon were produced.

2021 ◽  
Vol 9 ◽  
Author(s):  
Malte Jörn Krafft ◽  
Jens Berger ◽  
Bodo Saake

The utilization of agricultural products and residues for the production of value-added and biobased products is a highly relevant topic in present research. Due to the natural recalcitrance of lignocellulosic biomass against enzymatic degradation, pretreatments are important requirement for further processes. For the raw material in this study, corn stover (CS) as highly available agricultural residue and maize silage (MS) as model substrate for an ensiled agricultural product were pretreated by steam refining. However, after processing a liquid fraction and fibers are present. Subsequent to steaming the fiber fraction is well characterized. Nonetheless, in depth characterizations of the filtrates are also important for their subsequent utilization. Decreasing molar masses from 7,900 g/mol to 1,100 g/mol for CS filtrates and 100.000–12.900 g/mol for MS filtrates were determined with increasing severity. Due to their proven inhibitory effect on microorganisms weak acids, furans and phenolic compounds within the liquid phased were analyzed. Especially formic acid increases with increasing severity from 0.27 to 1.20% based on raw material for CS and from 0.07 to 0.23% based on raw material for MS. Further GC/MS measurements indicate, that up to 8.25% (CS filtrate) and 5.23% (MS filtrates) of the total peak area is related to inhibitory phenols. Considering the data, detoxification strategies are of non-negligible importance for filtrates after steam refining and should be considered for further research and process or parameter optimizations. An alternative may be the application of milder process conditions in order to prevent the formation of inhibitory degradation products or the dilution of the gained filtrates.


2008 ◽  
Vol 42 (2) ◽  
pp. 160-166 ◽  
Author(s):  
Encarnación Ruiz ◽  
Cristóbal Cara ◽  
Paloma Manzanares ◽  
Mercedes Ballesteros ◽  
Eulogio Castro

2018 ◽  
Vol 156 ◽  
pp. 03022 ◽  
Author(s):  
Diah Meilany ◽  
MTAP Kresnowati ◽  
Tjandra Setiadi

Biorefinery industry used lignocellulosic biomass as the raw material. Oil Palm Empty Fruit Bunch (OPEFB) is one of Indonesian potential lignocellulosic biomass, which consists of hemicellulose with xylan as the main component. Xylitol production via fermentation could use this xylan since it can be converted into xylose. However, the structure of OPEFB is such that hemicellulose is protected in a way that will hinder hydrolysis enzyme to access it. Considering that hemicellulose is more susceptible to heat than cellulose, a hydrothermal process was applied to pre-treat OPEFB before it was hydrolyzed enzymatically. The aim of the research is to map the effect of temperature, solid loading and time of pre-treatment process to obtain and recover as much as possible accessible hemicellulose from OPEFB. The results showed that temperature gave more significant effect than time and solid loading for glucose recovery of OPEFB residues. While xylose recovery varies greatly with temperature, but solid loading and time gave less significant effect.


Holzforschung ◽  
2020 ◽  
Vol 74 (5) ◽  
pp. 469-475
Author(s):  
Yinling Zhao ◽  
Shengling Xiao ◽  
Jinquan Yue ◽  
Dingyuan Zheng ◽  
Liping Cai

AbstractIn this study, poplar chemi-mechanical pulp was used as a raw material to investigate the effect of enzymatic hydrolysis lignin (EHL) content on the tensile strength and hydrophobicity of molded fiber materials (MFMs). The tensile strength and hydrophobic properties of the fabricated MFMs with different EHL contents were evaluated, and changes in their microstructure, chemical structure, and thermal stability were characterized via scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric (TG) analysis, respectively. Results show that under the experimental conditions used herein, the addition of EHL could increase the tensile strength and surface water contact angle of MFMs up to 20.3 MPa and 95.0°, respectively. The SEM observations indicate that the addition of EHL expanded the contact area between the EHL and fibers, thereby reducing the holes between fibers. The FTIR and TG analyses indicated that hot-pressing degraded EHL to form small molecular substances and improved the reaction with aldehydes produced via carbohydrate degradation, improving both the inter-fiber bonding strength and hydrophobicity of the MFM surface.


Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4552 ◽  
Author(s):  
Merve Nazli Borand ◽  
Asli Isler Kaya ◽  
Filiz Karaosmanoglu

Pressure, temperature, and retention time are the most studied parameters in steam explosion pretreatment. However, this work aimed to fix these parameters and to evaluate the influences of several less investigated steam explosion parameters on the saccharification yield in hydrolysis. In this study, firstly, pinewood samples smaller than 200 µm were treated with steam explosion at 190 °C for 10 min. The variable parameters were biomass loading, N2 pressure, and release time. Steam-exploded samples were hydrolyzed with the Trichoderma reesei enzyme for saccharification for 72 h. The sugar content of the resultant products was analyzed to estimate the yield of sugars (such as glucose, xylose, galactose, mannose, and arabinose). The best glucose yield in the pulp was achieved with 4 g of sample, N2 pressure of 0.44 MPa, and short release time (22 s). These conditions gave a glucose yield of 97.72% in the pulp, and the xylose, mannose, galactose, and arabinose yields in the liquid fraction were found to be 85.59%, 87.76%, 86.43%, and 90.3%, respectively.


Energies ◽  
2018 ◽  
Vol 11 (4) ◽  
pp. 886 ◽  
Author(s):  
Rafał Łukajtis ◽  
Piotr Rybarczyk ◽  
Karolina Kucharska ◽  
Donata Konopacka-Łyskawa ◽  
Edyta Słupek ◽  
...  

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3653 ◽  
Author(s):  
Robert Balan ◽  
Andrzej Antczak ◽  
Simone Brethauer ◽  
Tomasz Zielenkiewicz ◽  
Michael H. Studer

Steam explosion is a well-known process to pretreat lignocellulosic biomass in order to enhance sugar yields in enzymatic hydrolysis, but pretreatment conditions have to be optimized individually for each material. In this study, we investigated how the results of a pretreatment optimization procedure are influenced by the chosen reaction conditions in the enzymatic hydrolysis. Beechwood was pretreated by steam explosion and the resulting biomass was subjected to enzymatic hydrolysis at glucan loadings of 1% and 5% employing either washed solids or the whole pretreatment slurry. For enzymatic hydrolysis in both reaction modes at a glucan loading of 1%, the glucose yields markedly increased with increasing severity and with increasing pretreatment temperature at identical severities and maximal values were reached at a pretreatment temperature of 230 °C. However, the optimal severity was 5.0 for washed solids enzymatic hydrolysis, but only 4.75 for whole slurry enzymatic hydrolysis. When the glucan loading was increased to 5%, glucose yields hardly increased for pretreatment temperatures between 210 and 230 °C at a given severity, and a pretreatment temperature of 220 °C was sufficient under these conditions. Consequently, it is important to precisely choose the desired conditions of the enzymatic hydrolysis reaction, when aiming to optimize the pretreatment conditions for a certain biomass.


2019 ◽  
Vol 11 (11) ◽  
pp. 6179-6188
Author(s):  
Bárbara Ribeiro Alves Alencar ◽  
Fernanda Leitão Vaz ◽  
Adauto Gomes Barbosa Neto ◽  
Katia Aparecida Aquino ◽  
Everardo Valadares de Sa Barretto Sampaio ◽  
...  

2018 ◽  
Vol 5 (1) ◽  
pp. 350
Author(s):  
Siti Maemunah ◽  
Achmad Ali S

Bio ethanol is a very attractive fuel source for communities or even countries that wish to be self-sustainable and not reliant on foreign resources. A variety of feedstock materials may be used to produce ethanol, such as glucose or starchy material (cassava, corn, etc.), by preparing it with a hydrolysis pre-treatment to form glucose. The enzymatic hydrolysis of starch requires at least two different enzymes such as α-amylase for liquefaction process and maltase for saccharification process. The main objective of this research is to produce sub-merged culture enzyme from Aspergillus sp that contained α-amylase and maltase enzymes in sufficient quantity to convert starch which is contained in cassava powder to form glucose. Aspergillus niger CCL 74 ITB and Aspergillus oryzae CCL ITB were cultivated in sub-merged culture. The main raw material of the medium had been varied between vinase from molasse and cake from peanut. Sub-merged culture from Aspergillus niger CCL74 ITB in the vinase medium gave higher a-amylase and maltase activities, compare to sub­ merged culture from A. oryzae CCL ITB. Using vinase from molasse gave higher enzymes yield than using medium from peanut cake.Keywords: α-amylase and Maltase, Sub-merged culture of Aspergillus niger. Aspergillus oryzae AbstrakBahan bakar hayati seperti bioetanol merupakan bahan bakar ramah lingkungan yang potensial dalam mengurangi impor BBM Indonesia. Rute utama pembuatan bioetanol adalah viafermentasi bahan berkarbohidrat. Bahan berkarbohidrat yang potensial dikembangkan di Indonesia dalam produksi bioetanol adalah singkong. Proses konversi pati dalam singkong menjadi etanol biasanya dilakukan melalui proses enzimatik yaitu proses likuefaksi oleh enzim α-amilase, proses sakarifikasi oleh enzim maltase dan fermentasi. Tujuan penelitian ini adalah mendapatkan kultur jamur Aspergillus sp. yang menghasilkan enzim α-amilase dan maltase dalam kuantitas memadai yang akan digunakan sebagai sumber enzim penghidrolisis pati dalam singkong. Jenis jamur yang digunakan Aspergillus niger CCL 74 ITB dan Aspergillus oryzae CCL ITB. Bahan baku utama medium divariasikan antara vinase dan bungkil kacang tanah. Kultur Aspergillus niger CCL74 ITB memberikan aktivitas a-amilase dan maltase yang lebih tinggi dibandingkan dengan kultur Aspergillus oryzae CCL ITB. Penggunaan vinase memberikan hasil yang lebih baik dibandingkan dengan medium bungkil kacang tanah dalam produksi kedua enzim.Kata Kunci: Enzim α-amilase, Glukoamilase, Aspergillus niger.  Aspergillus oryzae


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