Sequential coupling of enzymatic hydrolysis and fermentation platform for high yield and economical production of 2, 3‐butanediol from cassava by metabolically engineered Klebsiella oxytoca

2020 ◽  
Author(s):  
Panwana Khunnonkwao ◽  
Sirima S Jantama ◽  
Kaemwich Jantama ◽  
Claire Joannis‐Cassan ◽  
Patricia Taillandier
Keyword(s):  
Enzymatic Hydrolysis ◽  
Klebsiella Oxytoca ◽  
High Yield ◽  
Sequential Coupling

scholarly journals A Novel Inulin-Mediated Ethanol Precipitation Method for Separating Endo-Inulinase From Inulinases for Inulooligosaccharides Production From Inulin

2021 ◽  
Vol 9 ◽  
Author(s):  
Xin Li ◽  
Qiannan Zhang ◽  
Wei Wang ◽  
Shang-Tian Yang
Keyword(s):  
Enzymatic Hydrolysis ◽  
Aspergillus Niger ◽  
Functional Food ◽  
Degree Of Polymerization ◽  
Precipitation Method ◽  
High Yield ◽  
Process Conditions ◽  
Food Ingredients ◽  
Ethanol Precipitation ◽  
Novel Method

Inulin is a kind of polysaccharide that can be obtained various biomass. Inulooligosaccharides (IOS), a kind of oligosaccharides that can be obtained from inulin by enzymatic hydrolysis using inulinases, have been regarded as the functional food ingredients. Commercially available inulinases produced by natural Aspergillus niger contained both endo- and exo-inulinase activities. For IOS production from inulin, it is desirable to use only endo-inulinase as exo-inulinase would produce mainly the monosacchairde fructose from inulin. In the present study, a simple inulin-mediated ethanol precipitation method was developed to separate endo- and exo-inulinases present in natural inulinases. IOS production from inulin using the enriched endo-inulinase was then optimized in process conditions including pH and temperature, achieving a high yield of ∼94%. The resultant IOS products had a degree of polymerization ranging from 2 to 7. The study demonstrated a novel method for obtaining partially purified or enriched endo-inulinase for IOS production from inulin in an efficient process.

scholarly journals Production of Cellulosic Ethanol from Enzymatically Hydrolysed Wheat Straws

2020 ◽  
Vol 10 (21) ◽  
pp. 7638
Author(s):  
Vasile-Florin Ursachi ◽  
Gheorghe Gutt
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Cellulosic Ethanol ◽  
Raw Material ◽  
High Yield ◽  
Liquid Ratio ◽  
Hydrolysis Process ◽  
Pretreatment Conditions ◽  
Pretreated Wheat Straw ◽  
First Time

The aim of this study is to find the optimal pretreatment conditions and hydrolysis in order to obtain a high yield of bioethanol from wheat straw. The pretreatments were performed with different concentrations of sulphuric acid 1, 2 and 3% (v/v), and were followed by an enzymatic hydrolysis that was performed by varying the solid-to-liquid ratio (1/20, 1/25 and 1/30 g/mL) and the enzyme dose (30/30 µL/g, 60/60 µL/g and 90/90 µL/g Viscozyme® L/Celluclast® 1.5 L). This mix of enzymes was used for the first time in the hydrolysis process of wheat straws which was previously pretreated with dilute sulfuric acid. Scanning electron microscopy indicated significant differences in the structural composition of the samples because of the pretreatment with H2SO4 at different concentrations, and ATR-FTIR analysis highlighted the changes in the chemical composition in the pretreated wheat straw as compared to the untreated one. HPLC-RID was used to identify and quantify the carbohydrates content resulted from enzymatic hydrolysis to evaluate the potential of using wheat straws as a raw material for production of cellulosic ethanol in Romania. The highest degradation of lignocellulosic material was obtained in the case of pretreatment with 3% H2SO4 (v/v), a solid-to-liquid ratio of 1/30 and an enzyme dose of 90/90 µL/g. Simultaneous saccharification and fermentation were performed using Saccharomyces cerevisiae yeast, and for monitoring the fermentation process a BlueSens equipment was used provided with ethanol, O2 and CO2 cap sensors mounted on the fermentation flasks. The highest concentration of bioethanol was obtained after 48 h of fermentation and it reached 1.20% (v/v).

Production with a High Yield of Bacterial Cellulose Nanocrystals by Enzymatic Hydrolysis

2019 ◽  
Vol 19 (03) ◽  
pp. 1950015
Author(s):  
Ricardo Brandes ◽  
Leticia de Souza ◽  
Claudimir Carminatti ◽  
Derce Recouvreux
Keyword(s):  
Enzymatic Hydrolysis ◽  
Bacterial Cellulose ◽  
Cellulose Nanocrystals ◽  
Primary Objective ◽  
High Yield ◽  
Low Density ◽  
Enzymatic Method ◽  
Citrate Buffer ◽  
Cellulose Hydrogel ◽  
Time Required

Bacterial cellulose nanocrystals are highly crystalline structures with nanoscopic scale dimensions that have received increased attention in the nanocomposites area. Its properties, such as large surface area, low density, mechanical strength and ease of modification, are attractive to the preparation many kinds of nanomaterials applied multifunctional in various fields. Besides, the cellulose nanocrystals are from abundant and renewable sources that are biodegradable. An altemative method is to obtain bacterial cellulose nanocrystal by enzymatic hydrolysis because it is, less expensive, it does not use chemicals and it requires much less energy. In this sense, the primary objective of this study was to produce bacterial cellulose using glycerol as a carbon source and isolate nanocrystals from bacterial cellulose using the enzymatic hydrolysis. This study also investigated the yield of nanocrystals depending on the weight of the bacterial cellulose hydrogel, keeping constant some enzymes. The study shows us that the enzymatic method has the best performance when using cellulose hydrogel 2[Formula: see text]g to 40[Formula: see text][Formula: see text]L cellulase enzyme (endoglucanase) and 1[Formula: see text]mL of citrate buffer. Also, it was observed that the yield of nanocrystals decrease with increasing time required for the hydrolysis.

scholarly journals Production of high yield sugars from Kappaphycus alvarezii using combined methods of chemical and enzymatic hydrolysis

2014 ◽  
Vol 42 ◽  
pp. 309-315 ◽  
Author(s):  
Faiqah Abd-Rahim ◽  
Helmi Wasoh ◽  
Mohd Rafein Zakaria ◽  
Arbakariya Ariff ◽  
Rizal Kapri ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Kappaphycus Alvarezii ◽  
High Yield ◽  
Combined Methods

Comprehensive utilization strategy of cellulose in a facile, controllable, high-yield preparation process of cellulose nanocrystals using aqueous tetrabutylphosphonium hydroxide

2021 ◽  
Author(s):  
Fangchao Cheng ◽  
Panpan Zhao ◽  
Tulong Ouyang ◽  
Jianping Sun ◽  
Yiqiang Wu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Cellulose Nanocrystals ◽  
High Yield ◽  
Utilization Rate ◽  
Preparation Process ◽  
Comprehensive Utilization ◽  
High Utilization ◽  
Hydrolysis Of ◽  
Utilization Strategy

Tetrabutylphosphonium hydroxide treatment of cellulose enabled facile, controllable, high-yield preparation of cellulose nanocrystals and effective enzymatic hydrolysis of cellulosic residue, resulting in a high utilization rate of more than 95%.

scholarly journals Ultrafast synthesis of isoquercitrin by enzymatic hydrolysis of rutin in a continuous-flow microreactor

2015 ◽  
Vol 80 (7) ◽  
pp. 853-866 ◽  
Author(s):  
Jun Wang ◽  
Gong An ◽  
Shuangshuang Gu ◽  
Hongsheng Cui ◽  
Xiangyang Wu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Continuous Flow ◽  
Biological Activities ◽  
Batch Reactor ◽  
Maximum Yield ◽  
Enzymatic Reaction ◽  
High Yield ◽  
Flow Microreactor ◽  
Wide Range ◽  
Hydrolysis Of

Isoquercitrin is a rare flavonol glycoside with a wide range of biological activities and is a key synthetic intermediate for the production of enzymatically modified isoquercitrin. In order to establish an ultrafast bioprocess for obtaining isoquercitrin, a novel continuous flow biosynthesis of isoquercitrin using the hesperidinase-catalyzed hydrolysis of rutin in a glass-polydimethylsiloxane (PDMS) microreactor was first carried out. Using the developed microchannel reactor (200?m width, 50?m depth, and 2 m length) with one T-shaped inlet and one outlet, the maximum yield of isoquercitrin (98.6%) was achieved in a short time (40 min) under the following optimum conditions: rutin concentration at 1 g L-1, hesperidinase concentration at 0.1 g mL-1, reaction temperature at 40?C, and a flow rate at 2 ?L min-1. The activation energy value Ea of the enzymatic reaction was 4.61 kJ mol-1, and the reaction rate and volumetric productivity were approximately 16.1-fold and 30% higher, respectively, than those in the batch reactor. Thus, the use of a continuous-flow microreactor for the enzymatic hydrolysis of rutin is an efficient and simple approach to achieve a relative high yield of isoquercitrin.

Preparation of N-Acetyl-D-Glucosamine by Enzymatic Hydrolysis of Amorphous Chitin

2010 ◽  
Vol 160-162 ◽  
pp. 1362-1365 ◽  
Author(s):  
Hong Zhu ◽  
Qiong Hou
Keyword(s):  
Enzymatic Hydrolysis ◽  
High Yield ◽  
Hydrolysis Of ◽  
Amorphous Chitin

Several crude enzymes including cellelase Tv, hemicellulase and lipase, papain as well as cellulase Ac were examined for the effective production of N-acetyl-D-glucosamine (GlcNAc) from amorphous α-chitin. Among the tested crude enzymes, cellulase Tv was found to be the most effective for directly degrading amorphous α-chitin to GlcNAc. High yield of GlcNAc was achieved by choosing the optimum hydrolytic conditions at pH 4.5 and 37°C. By gradually adding, in three tantamount cases, the amount of cellulase Tv to amorphous α-chitin, the yield of GlcNAc reach 55.0%.

A Review: Klebsiella pneumoniae, Klebisellaoxytoca and Biotechnology

2021 ◽  
Vol 26 (3) ◽  
pp. 2567-2586
Author(s):  
CATERINA TOMULESCU ◽  
◽  
MIȘU MOSCOVICI ◽  
IRINA LUPESCU ◽  
ROXANA MĂDĂLINA STOICA ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Genetic Manipulation ◽  
Klebsiella Oxytoca ◽  
Cost Effective ◽  
Biochemical Properties ◽  
High Yield ◽  
Natural Environments ◽  
Klebsiella Species ◽  
Bulk Chemicals ◽  
Plant Growth Promoting Activities

Biotechnology, molecular biology and genetic engineering, and bioprospecting play a crucial role in our common future, enabling industrially important microorganisms to ensure sustainable products (fuels, chemicals, pharmaceuticals, food, drug delivery systems, medical devices etc.) and new bioeconomic opportunities. Biotechnological applications are able to provide cost-effective green alternatives to conventional industrial processes, which are currently affecting the nature and biodiversity. Klebsiella species are among the well-studied microbes both in medicine field, as ones of the most resilient opportunistic pathogens, and in industry, due to their promising biochemical properties, and their potential as better hosts than other microorganisms, for i.e. in genetic manipulation. Klebsiella oxytoca and Klebsiella pneumoniae are ubiquitously found in natural environments, but also as commensals in the human gut, and associated with a high-resistance to the first-line antibiotics. However, these specific strains are continuously isolated and studied for different industrial purposes (i.e. bulk chemicals and biofuels production, medical diagnosis, nanoparticles and exopolysaccharides synthesis, plant growth promoting activities, bioremediation and biodegradation agents etc.), and scientific results regarding their biotechnological potential could generate big impact for global bioeconomy development. Recently, research in synthetic biology gained a lot of attention, and new techniques highlight ways to reprogramme these microbial cells in view of high-yield or high-quality new chemicals obtainment. Therefore, some scientific research niches are emerging in biotechnology, and unknown metabolic pathways and genes are identified and further studied, to provide alternative solutions to the global challenges.

Sign in / Sign up

Export Citation Format

Share Document