STUDY REGARDING THE OPTIMAL CONDITIONS FOR REDUCING SUGARS PRODUCTION FROM WHEAT STRAWS BY ENZYMATIC HYDROLYSIS

2017 ◽  
Vol 16 (10) ◽  
pp. 2347-2352
Author(s):  
Eufrozina Albu ◽  
Laura-Carmen Apostol
2013 ◽  
Vol 275-277 ◽  
pp. 1662-1665 ◽  
Author(s):  
Qiang Li ◽  
Juan Juan Fei ◽  
Xu Ding Gu ◽  
Geng Sheng Ji ◽  
Yang Liu ◽  
...  

This study aims to establish a natural cellulosic biomass pretreatment process using ionic liquid (IL) for efficient enzymatic hydrolysis and second generation bioethanol. The IL 1-Butyl-3-methylimidazolium Chloride/FeCl3 ([Bmim]Cl/FeCl3) was selected in view of its low temperature pretreatment ability and the potential of accelerating enzymatic hydrolysis, and it could be recyclable. The yield of reducing sugars from sugarcane residue pretreated with this IL at 80 oC for 1 h reached 46.8% after being enzymatically hydrolyzed for 24 h. Sugarcane residue regenerated were hydrolyzed more easily than that treated with water. The fermentability of the hydrolyzates, obtained after enzymatic saccharification of the regenerated sugarcane residue, was transformed into bioethanol using Candida shehatae. This microbe could absorb glucose and xylose efficiently, and the ethanol production was 0.38 g/g glucose within 30 h fermentation. In conclusion, the metal ionic liquid pretreatment in low temperature shows promise as pretreatment solvent for natural biomass.


2021 ◽  
Vol 6 (1) ◽  
pp. 156-164
Author(s):  
Jessica E. Guzmán-Pérez ◽  
◽  
Oscar J. Salinas-Luna ◽  
Ernesto Favela-Torres ◽  
Nohemi López-Ramírez ◽  
...  

Water hyacinth (Eichhornia crassipes) is considered a pernicious herb in many parts of the world due to its rapid growth. However, for its high content of cellulose and hemicellulose, it could be considered as raw material to produce fermentable sugars. In this work, the effect of sulfuric acid concentration by thermochemical pretreatment and enzymatic hydrolysis on the release of sugars from water hyacinth was evaluated. Initially, the effect of the sulfuric acid concentration from 1.5 to 9% at 120 ºC was evaluated. With 1.5%, the release of reducing sugars was 160 milligrams of reducing sugars per gram of dry matter (mg red-sug/g dm). After the thermochemical pretreatment, the enzymatic hydrolysis with the cellulase complex (NS22086) allowed obtaining a reducing sugars concentration up to 317 mg red-sug/g dm. These thermochemical and enzymatic approaches to recover reducing sugars from water hyacinth is promising and should be evaluated for bioprocess using reducing sugars as the main source of carbon, such as bioethanol production.


2018 ◽  
Vol 57 (31) ◽  
pp. 10105-10117 ◽  
Author(s):  
Mood Mohan ◽  
Narendra Naik Deshavath ◽  
Tamal Banerjee ◽  
Vaibhav V. Goud ◽  
Veeranki Venkata Dasu

2021 ◽  
Vol 5 (2) ◽  
pp. 289-294
Author(s):  
Zeenat Ibrahim Saulawa ◽  
Lawal Nura ◽  
Muntari Bala ◽  
Abdullahi A. Iman

The effectiveness of alkaline hydrogen peroxide as a suitable choice of pretreatment for the conversion of millet husk to reducing sugars using cellulase enzyme for hydrolysis and subsequent ethanol production was determined. The effects of three variables on reducing sugar production from millet husk were determined using one factor at a time (OFAT) method namely; peroxide concentration, pretreatment time and pretreatment temperature. From the results, it was observed that a significant (P<0.05) amount of reducing sugars were lost during pretreatment of millet husk. The untreated group which was only physically pretreated (milled) however yielded a significantly higher (P<0.05) reducing sugar concentration of 10.67mg/ml after enzymatic hydrolysis while the highest reducing sugar concentration of 4.82mg/ml was obtained using 0.375%v/v peroxide concentration for 60minutes at 250C. Therefore, pretreatment of biomass with alkaline hydrogen peroxide may be more suitable for feedstock with high lignin contents than millet husk.


2016 ◽  
Vol 15 (2) ◽  
pp. 133-141 ◽  
Author(s):  
Eva Ürgeová ◽  
Katarína Vulganová

Abstract AHyaluronic acid (HA) is part of the extracellular matrix of connective, epithelial and neural tissues, as well as the synovial fluid, skin, and cartilage. It is composed of repeating disaccharide units of D-glucuronic acid and N-acetyl glucosamine. Hyaluronic acid is used in abdominal surgery, ophthalmology, dermatology, rhinology; it is usable for the osteoarthritis treatment. The membranes of eggshell are a natural source of hyaluronic acid, collagen, glycosaminoglycan and collagenous proteins. In paper, we tested the possibility of extraction hyaluronic acid from the eggshell membranes by enzymatic hydrolysis. We identified optimal conditions of hydrolysis with trypsin at reaction temperature of 37 °C and pH 8; with pepsin at 40 °C and pH 3, as well as with papain at 60 °C and pH 7.5. The content of hyaluronic acid in samples was determined spectrophotometrically using the carbazole method. The experimental results showed a yield of ~ 4 -4.5 % hyaluronic acid per 1 g of dry eggshell membranes.


2021 ◽  
Author(s):  
SAHELI GHOSAL ◽  
JAYATI BHOWAL

Abstract The present study investigated the usefulness of flaxseed meals as a novel feedstock for the production of bioethanol. The proximate composition of the flaxseed meal was carried out before the pretreatment of the flaxseed meal. In this study, flaxseed meal was pretreated with dilute acid, alkali, and aqueous for disruption of lignocellulosic compounds. The acid pretreated flaxseed meal was used for enzymatic hydrolysis by different enzymes (cellulase, α-amylase, and cellulase combined with α-amylase) for better release of reducing sugar. The cellulose conversion to reducing sugar was significantly higher for acid pretreated flaxseed meals. After enzymatic hydrolysis with cellulase, cellulose conversions to reducing sugars were found to be significantly higher than those of α-amylase and cellulase combined with α-amylase. The bioethanol production was also investigated. The fermentation process was carried out by using baker’s yeast (Saccharomyces cerevisiae) with the acid pretreated flaxseed meal enzymatic hydrolyzate. Maximum ethanol production (0.11 g/l) was achieved from the fermented medium obtained from the acid pretreated flaxseed meal followed by enzymatic hydrolysis by using cellulase enzyme. The structural analysis of bioethanol was also investigated by FTIR.


2021 ◽  
Author(s):  
Si Lu ◽  
Qiong Wang ◽  
Xiaoman Wang ◽  
Cuiyi Liang ◽  
Juan Fu ◽  
...  

Abstract The efficient conversion of hemicellulose and cellulose in lignocellulosic biomass to reducing sugars remains as one major challenge for the development of biorefinery. In this work, corncob saccharification in the aqueous phase was realized efficiently via pretreatment by magnetic carbon-based solid acid (MMCSA) catalyst, combined with the subsequent in situ enzymatic hydrolysis (occurring in the same pretreatment system after MMCSA separation). Under the optimized pretreatment conditions (the ratio of corncob, catalyst and water is 1:1:20 (g:g:mL), 160°C for 20 min) and in situ enzymatic hydrolysis (cellulase loading of 20 FPU / g, 24 h), an xylose yield of 88.77% and an enzymatic digestibility of 91.24% were obtained, respectively. Compared with the traditional enzymatic process, the present in situ enzymatic system has advantages of reduced enzyme loading, water consumption, and improved saccharification efficiency. Thus, this study provides a more sustainable and effective method for the saccharification of hemicellulose and cellulose in the corncob to produce reducing sugars.


Author(s):  
María Laura Montoro ◽  
María Herrero ◽  
Arminda Mamaní ◽  
María Sardella ◽  
Martha Vallejo ◽  
...  

Abstract Melon is one of the main horticultural crops in the province of San Juan, Argentina. An excess of 20% of its production is not marketed for various reasons. To take advantage of this biomass, acid pretreatments (PA), acid combined with ultrasound (PAU), were applied to evaluate increases in the bioavailability of sugars for the production of 2G bioethanol. The results showed that under the optimal conditions of both pretreatments: concentration of 2% sulfuric acid, time of 30 minutes, the temperature of 55 °C and solid: liquid ratio11:1, followed by enzymatic hydrolysis using cellulase, hemicellulose and pectinase, increases of 111 and 576% are achieved in the content of fermentable sugars, compared to untreated melon. Acid pretreatment combined with ultrasound and enzymatically hydrolyzed, using cellulase, hemicellulase, and pectinase, turned out to be the best alternative in terms of increasing fermentable sugars, obtaining 38.99 mL of bioethanol per kg of melon.


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