scholarly journals ENZYMATIC HYDROLYSIS OF SOLUBLE CELLULOSE DERIVATIVES AS MEASURED BY CHANGES IN VISCOSITY

1950 ◽  
Vol 33 (5) ◽  
pp. 601-628 ◽  
Author(s):  
Hillel S. Levinson ◽  
Elwyn T. Reese
Keyword(s):  
Enzymatic Hydrolysis ◽  
Intrinsic Viscosity ◽  
Reducing Sugars ◽  
Enzyme System ◽  
Molecular Size ◽  
Cellulose Hydrolysis ◽  
Reducing Sugar ◽  
Cellulose Derivatives ◽  
Enzyme Preparations ◽  
Hydrolysis Of

Observation of changes in fluidity is presented as a method for following the enzymatic hydrolysis of soluble cellulose derivatives. The activity of different cell-free enzyme preparations may be compared by this method, providing certain precautions are observed. In general, results obtained by use of the fluidity method are similar to those obtained using the reducing sugar technique, indicating that the same enzyme system is measured by the two methods. Changes in the DP of the substratum may be followed within certain limits of molecular size. Results indicate that a random splitting of CMC occurs during enzymatic hydrolysis, with a concomitant decrease in intrinsic viscosity and an increase in reducing sugars. Certain inadequacies of the cellulose-cellobiose-glucose theory, together with more recent findings, have led to the postulation of an alternate explanation of the mechanism of cellulose hydrolysis.

scholarly journals The effect of beta-glucosidase supplementation on enzymatic hydrolysis of cellulose in hydrothermally pretreated sugar beet shreds

2018 ◽  
pp. 1-9
Author(s):  
Mirjana Antov ◽  
Aleksandar Fistes
Keyword(s):  
Enzymatic Hydrolysis ◽  
Sugar Beet ◽  
Reducing Sugars ◽  
Cellulose Hydrolysis ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Untreated Material ◽  
Hydrolysis Of Cellulose ◽  
Beta Glucosidase ◽  
Hydrolysis Of

Sugar beet shreds were pretreated by hydrothermal procedure to investigate the effect of beta-glucosidase supplementation at different substrate loading on the rate of cellulose hydrolysis. Cellulose in the hydrothermally pretreated substrate was more efficiently hydrolyzed by enzymes than in untreated material, resulting in more than two times higher release of reducing sugars. In the investigated range of solids load, supplementation of fungal cellulases cocktail by beta-glucosidase increased production of reducing sugars from substrates, while 0.25 U/g was sufficient to achieve the highest effect under applied conditions.

scholarly journals Analysis of pretreatments of sugar beet shreds for bioethanol production in respect of cellulose hydrolysis and waste flows

2011 ◽  
pp. 223-230
Author(s):  
Darjana Ivetic ◽  
Vesna Vasic ◽  
Marina Sciban ◽  
Mirjana Antov
Keyword(s):  
Enzymatic Hydrolysis ◽  
Sugar Beet ◽  
Reducing Sugars ◽  
Cellulose Hydrolysis ◽  
Raw Material ◽  
Bioethanol Production ◽  
Lignin Removal ◽  
Chemical Pretreatments ◽  
Hydrolysis Of

This paper analyzes some chemical pretreatments of sugar beet shreds concerning generated waste flows and yield of reducing sugars obtained by enzymatic hydrolysis of pretreated material. Waste flows produced in pretreatments of sugar beet shreds originated from pectin and lignin removal from raw material. Suitability of substrates prepared in single and two-step pretreatment procedure for enzymatic hydrolysis was determined based on the yield of reducing sugars released by cellulase action on them, while different possibilities of processing of wastewaters were discussed based on the characteristic of waste flows.

β-Glucosidase: microbial production and effect on enzymatic hydrolysis of cellulose

1977 ◽  
Vol 23 (2) ◽  
pp. 139-147 ◽  
Author(s):  
D. Sternberg ◽  
P. Vuayakumar ◽  
E. T. Reese
Keyword(s):  
Enzymatic Hydrolysis ◽  
Liquid Culture ◽  
Enzyme System ◽  
Microbial Production ◽  
Enzymatic Conversion ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Black Aspergilli ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of ◽  
Predominant Product

The enzymatic conversion of cellulose is catalyzed by a multiple enzyme system. The Trichoderma enzyme system has been studied extensively and has insufficient β-glucosidase (EC 3.2.1.21) activity for the practical saccharification of cellulose. The black aspergilli (A. niger and A. phoenicis) were superior producers of β-glucosidase and a method for production of this enzyme in liquid culture is presented. When Trichoderma cellulase preparations are supplemented with β-glucosidase from Aspergillus during practical saccharifications, glucose is the predominant product and the rate of saccharification is significantly increased. The stimulatory effect of β-glucosidase appears to be due to the removal of inhibitory levels of cellobiose.

scholarly journals Enzymatic hydrolysis of oil palm empty fruit bunch to produce reducing sugar and its kinetic Hidrolisis enzimatik tandan kosong kelapa sawit untuk menghasilkan gula pereduksi dan kinetikanya

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Vera BARLIANTI ◽  
Deliana DAHNUM ◽  
. MURYANTO ◽  
Eka TRIWAHYUNI ◽  
Yosi ARISTIAWAN ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Oil Palm ◽  
Volume Ratio ◽  
Enzyme Concentration ◽  
Reducing Sugar ◽  
Economic Feasibility ◽  
First Order ◽  
Empty Fruit Bunches ◽  
Hydrolysis Process ◽  
Hydrolysis Of

Abstrak Sebagai salah satu Negara penghasil minyak kelapa sawit mentah (CPO), Indonesia juga menghasilkan tandan kosong kelapa sawit (TKKS) dalam jumlah besar. TKKS terdiri dari-tiga-komponen utama, yaitu selulosa, hemiselulosa, dan lignin. Pengolahan awal TKKS secara alkalindi ikuti dengan hidrolisis TKKS secara enzimatik menggunakan kombinasi enzim selulase dan β-glukosidase akan menghasilkan gula-gula yang mudah difermentasi.  Penelitian ini bertujuan untuk mempelajari pengaruh konsentrasi substrat, kon-sentrasi enzim, dan suhu selama proses hidrolisis berlangsung.  Hasil yang diperoleh menunjukkan bahwa konsentrasi gula maksimum (194,78 g/L) dicapai pada konsentrasi TKKS 20% (b/v), konsentrasi campuran enzim yang terdiri dari selulase dan β-1,4 glukosidase sebesar 3,85% (v/v), dan suhu 50oC. Perbandingan antara selulase dan β-1,4 glukosidase adalah 5:1 dengan masing-masing aktivitas enzim sebesar 144.5 FPU/mL dan 63 FPU/mL. Hasil penelitian juga menunjukkan bahwa model kinetika yang sesuai untuk proses hidrolisis TKKS secara enzimatik adalah model kinetika Shen dan Agblevor dengan reakside aktivasi enzim orde satu.  Hasil ini mendukung studi kelayakan ekonomi dalam pemanfaatan TKKS untuk produksi bioetanol.AbstractAs one of the crude palm oil producers, Indonesia also produces empty fruit bunches (EFB)in large quantities. The oil palm EFB consist of cellulose, hemicellulose and lignin. Alkaline pretreatment of EFB, followed by enzymatic hydro-lysis of cellulose using combination of cellulase and β-glucosidase enzymes produce fermentable sugars. This paper reported the effects of substrate loading, enzyme concentration, and temperature of hydrolysis process on reducing sugar production. The  maximum  sugar  concentration (194.78 g/L) was produced at 50oC using 20% (w/v) EFB and 3.85% (v/v) mixed enzymes of cellulase and β-1,4 glucosidase in volume ratio of 5:1 (v/v), with enzyme activity of 144.5 FPU/mL and 63 FPU/mL, respectively. The results also showed that the suitable kinetic model for enzymatic hydrolysis process of oil palm EFB follow Shen and Agblevor model with first order of enzyme deactivation. These results support the economic feasibility study in utilization of EFB of oil palm for bioethanol production.    

Reducing sugar loss in enzymatic hydrolysis of ethylenediamine pretreated corn stover

2017 ◽  
Vol 224 ◽  
pp. 405-410 ◽  
Author(s):  
Wen-Chao Li ◽  
Xia Li ◽  
Lei Qin ◽  
Jia-Qing Zhu ◽  
Xiao Han ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Corn Stover ◽  
Reducing Sugar ◽  
Pretreated Corn Stover ◽  
Hydrolysis Of ◽  
Sugar Loss

scholarly journals Effect of Subsequent Dilute Acid and Enzymatic Hydrolysis on Reducing Sugar Production from Sugarcane Bagasse and Spent Citronella Biomass

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Robinson Timung ◽  
Narendra Naik Deshavath ◽  
Vaibhav V. Goud ◽  
Venkata V. Dasu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Sugarcane Bagasse ◽  
Crystallinity Index ◽  
Sem Analysis ◽  
Reducing Sugar ◽  
Dilute Acid Pretreatment ◽  
Crystalline Cellulose ◽  
Dilute Acid ◽  
Acid Pretreatment ◽  
Hydrolysis Of

This work was aimed at investigating the effect of process parameters on dilute acid pretreatment and enzymatic hydrolysis of spent citronella biomass (after citronella oil extraction) and sugarcane bagasse on total reducing sugar (TRS) yield. In acid pretreatment, the parameters studied were acid concentration, temperature, and time. At the optimized condition (0.1 M H2SO4, 120°C, and 120 min), maximum TRS obtained was 452.27 mg·g−1and 487.50 mg·g−1for bagasse and citronella, respectively. Enzymatic hydrolysis of the pretreated biomass usingTrichoderma reesei26291 showed maximum TRS yield of 226.99 mg·g−1for citronella and 282.85 mg·g−1for bagasse at 10 FPU, 50°C, and 48 hr. The maximum crystallinity index (CI) of bagasse and citronella after acid pretreatment obtained from X-ray diffraction analysis was 64.41% and 56.18%, respectively. Decreased CI after enzymatic hydrolysis process to 37.28% and 34.16% for bagasse and citronella, respectively, revealed effective conversion of crystalline cellulose to glucose. SEM analysis of the untreated and treated biomass revealed significant hydrolysis of holocellulose and disruption of lignin.

PRETREATMENT OF MILLET HUSK USING ALKALINE HYDROGEN PEROXIDE TO ENHANCE ENZYMATIC HYDROLYSIS FOR REDUCING SUGAR PRODUCTION

2021 ◽  
Vol 5 (2) ◽  
pp. 289-294
Author(s):  
Zeenat Ibrahim Saulawa ◽  
Lawal Nura ◽  
Muntari Bala ◽  
Abdullahi A. Iman
Keyword(s):  
Hydrogen Peroxide ◽  
Enzymatic Hydrolysis ◽  
Reducing Sugars ◽  
Reducing Sugar ◽  
Sugar Concentration ◽  
Sugar Production ◽  
Alkaline Hydrogen Peroxide ◽  
Pretreatment Time ◽  
Pretreatment Temperature ◽  
Reducing Sugar Concentration

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.

Blending of cellulolytic enzyme preparations from different fungal sources for improved cellulose hydrolysis by increasing synergism

RSC Advances ◽  
2014 ◽  
Vol 4 (84) ◽  
pp. 44726-44732 ◽  
Author(s):  
Mukund Adsul ◽  
Bhawna Sharma ◽  
Reeta Rani Singhania ◽  
Jitendra Kumar Saini ◽  
Ankita Sharma ◽  
...  
Keyword(s):  
Wheat Straw ◽  
Cellulose Hydrolysis ◽  
Cellulolytic Enzyme ◽  
Enzyme Preparations ◽  
Fungal Enzyme ◽  
Enzyme Cocktail ◽  
Different Types ◽  
Hydrolysis Of

A prepared enzyme cocktail from different fungal enzyme preparations increases the hydrolysis of avicel/wheat straw by increasing synergism between the same or different types of cellulases.

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