Organosolv lignin properties and their effects on enzymatic hydrolysis

Lignin plays a crucial role in enzymatic hydrolysis of lignocellulosic biomass. To evaluate the correlation between lignin properties and its effects on enzymatic hydrolysis, five organosolv lignins (OLs) were isolated from woody biomass, and their physico-chemical properties and structural features were characterized. The effects of OL addition on enzymatic hydrolysis of microcrystalline cellulose (pure cellulose) were assessed first, which showed their disparate effects. The addition of three OLs increased the 72 h hydrolysis yield by 7.4% to 10.1%, while the addition of other two OLs reduced the 72 h hydrolysis yield by 3.2% to 20.4%. A strong correlation between the enzyme distribution coefficient on lignins and the 72 h hydrolysis yields indicated that the enzyme-lignin interaction played a significant role in determining the lignin effects. More importantly, a correlation between lignin properties (hydrophobicity, zeta potential, and particle size) and the enzyme distribution coefficient was established. Identifying the key lignin properties will give insights to reduce the lignin inhibition by altering the lignin properties, thereby promoting enzymatic hydrolysis of lignocellulose.

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The Impact of Filler Geometry on Polylactic Acid-Based Sustainable Polymer Composites

Molecules ◽

10.3390/molecules26010149 ◽

2020 ◽

Vol 26 (1) ◽

pp. 149

Author(s):

Karol Leluk ◽

Stanisław Frąckowiak ◽

Joanna Ludwiczak ◽

Tomasz Rydzkowski ◽

Vijay Kumar Thakur

Keyword(s):

Polymer Composites ◽

Polylactic Acid ◽

Matrix Material ◽

Chemical Properties ◽

Precipitated Calcium Carbonate ◽

Cellulose Fibres ◽

Shape Factors ◽

Pure Cellulose ◽

Physico Chemical ◽

The Impact

Recently, biocomposites have emerged as materials of great interest to the scientists and industry around the globe. Among various polymers, polylactic acid (PLA) is a popular matrix material with high potential for advanced applications. Various particulate materials and nanoparticles have been used as the filler in PLA based matrix. One of the extensively studied filler is cellulose. However, cellulose fibres, due to their hydrophilic nature, are difficult to blend with a hydrophobic polymer matrix. This leads to agglomeration and creates voids, reducing the mechanical strength of the resulting composite. Moreover, the role of the various forms of pure cellulose and its particle shape factors has not been analyzed in most of the current literature. Therefore, in this work, materials of various shapes and shape factors were selected as fillers for the production of polymer composites using Polylactic acid as a matrix to fill this knowledge gap. In particular, pure cellulose fibres (three types with different elongation coefficient) and two mineral nanocomponents: precipitated calcium carbonate and montmorillonite were used. The composites were prepared by a melt blending process using two different levels of fillers: 5% and 30%. Then, the analysis of their thermomechanical and physico-chemical properties was carried out. The obtained results were presented graphically and discussed in terms of their shape and degree of filling.

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Synergistic effects of pH and organosolv lignin addition on the enzymatic hydrolysis of organosolv-pretreated loblolly pine

RSC Advances ◽

10.1039/c8ra00902c ◽

2018 ◽

Vol 8 (25) ◽

pp. 13835-13841 ◽

Cited By ~ 8

Author(s):

Chenhuan Lai ◽

Maobing Tu ◽

Qiang Yong ◽

Shiyuan Yu

Keyword(s):

Enzymatic Hydrolysis ◽

Loblolly Pine ◽

Synergistic Effects ◽

Organosolv Lignin ◽

Effects Of Ph ◽

Hydrolysis Of

The effect of ethanol organosolv lignin (EOL) on enzymatic hydrolysis was examined at pH 4.8–6.0.

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Optimization of olive pomace enzymatic hydrolysis for fermentable sugar production

Nutrition & Food Science ◽

10.1108/nfs-03-2016-0038 ◽

2016 ◽

Vol 46 (6) ◽

pp. 778-790 ◽

Cited By ~ 2

Author(s):

Ghassan Abo Chameh ◽

Fadi Kheder ◽

Francois Karabet

Keyword(s):

Enzymatic Hydrolysis ◽

Ph Value ◽

Maximum Yield ◽

Olive Pomace ◽

Mixing Rate ◽

Content Type ◽

Hydrolysis Yield ◽

Pretreatment Time ◽

Hydrolysis Conditions ◽

Hydrolysis Of

Purpose The purpose of this paper was to find out the appropriate enzymatic hydrolysis conditions of alkali pretreated olive pomace (OP) which enable maximum yield of reducing sugar. Design/methodology/approach The commercial enzymatic preparation (Viscozyme® L) was used for the hydrolysis of OP. The effects of pretreatment, time, temperature, pH, enzyme quantity and substrate loading on the hydrolysis yield were investigated. Findings This study showed that enzymatic hydrolysis of OP using Viscozyme® L can be successfully performed at 50°C. Alkaline pretreatment step of OP prior the enzymatic hydrolysis was indispensable. The hydrolysis yield of alkaline pretreated OP was 2.6 times higher than the hydrolysis yield of untreated OP. Highest hydrolysis yield (33.5 ± 1.5 per cent) was achieved after 24 h using 1 per cent (w/v) OP load in the presence of 100 μl Viscozyme® L at 50°C and pH 5.5 with mixing rate of 100 rpm (p = 0.05). Originality/value Reaction time, temperature, pH value and enzyme quantity were found to have a significant effect on enzymatic hydrolysis yield of alkali pretreated of OP. Although high-solid loadings of OP lowered the hydrolysis yield, it produced higher concentration of reducing sugars, which may render the OP conversion process more economically feasible.

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Lactose-free Dulce de leche: compositional characterization, browning and texture profile

Journal of Dairy Research ◽

10.1017/s0022029921000820 ◽

2021 ◽

pp. 1-5

Author(s):

Caroline Barroso dos Anjos Pinto ◽

Isis Rodrigues Toledo Renhe ◽

Carolina Carvalho Ramos Viana ◽

Ítalo Tuler Perrone ◽

Luiz Fernando Cappa de Oliveira ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Chemical Characteristics ◽

High Demand ◽

Free Products ◽

Texture Profile ◽

Physico Chemical ◽

Texture Parameters ◽

Reaction Texture ◽

Hydrolysis Of ◽

Compositional Characterization

Abstract Our objective was to elaborate lactose-free Dulce de leche (DL) and evaluate the influence of the hydrolysis of this sugar on the attributes of the products. Fluid milk used was divided into two portions and, in one of them, enzymatic hydrolysis of lactose was carried through. Next, the homogenization of milk was performed at 20 MPa. Four different treatments were studied. The final products were evaluated in relation to their composition and physico-chemical characteristics. The main results show that the homogenized lactose-free DL obtained a higher concentration of free 5-Hydroxymethylfurfural (HMF) (133.77 ± 3.42 μmol l−1). Consequently, browning was more intense due to Maillard Reaction. Texture parameters were higher (1611.00 ± 598.78 g hardness and 19.52 ± 2.46 g gumminess) when compared to the homogenized traditional product (28.45 ± 1.16 μmol l−1 free HMF, 437.17 ± 279.3 g hardness, and 406.20 ± 311.69 g gumminess). Lactose-free products are in high demand by consumers; however, the results of this work highlight the challenges to properly control the browning and the texture parameters of DL.

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Enzymatic sugar production from elephant grass and reed straw through pretreatments and hydrolysis with addition of thioredoxin-His-S

Biotechnology for Biofuels ◽

10.1186/s13068-019-1629-y ◽

2019 ◽

Vol 12 (1) ◽

Cited By ~ 4

Author(s):

Xianqin Lu ◽

Can Li ◽

Shengkui Zhang ◽

Xiaohan Wang ◽

Wenqing Zhang ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Pennisetum Purpureum ◽

Commercial Application ◽

Hydrolysis Lignin ◽

Cellulose Content ◽

Sugar Production ◽

Elephant Grass ◽

Reed Straw ◽

Hydrolysis Yield ◽

Hydrolysis Of

Abstract Background The bioconversion of lignocellulose to fermentable C5/C6-saccharides is composed of pretreatment and enzymatic hydrolysis. Lignin, as one of the main components, resists lignocellulose to be bio-digested. Alkali and organosolv treatments were reported to be able to delignify feedstocks and loose lignocellulose structure. In addition, the use of additives was an alternative way to block lignin and reduce the binding of cellulases to lignin during hydrolysis. However, the relatively high cost of these additives limits their commercial application. Results This study explored the feasibility of using elephant grass (Pennisetum purpureum) and reed straw (Phragmites australis), both of which are important fibrous plants with high biomass, no-occupation of cultivated land, and soil phytoremediation, as feedstocks for bio-saccharification. Compared with typical agricultural residues, elephant grass and reed straw contained high contents of cellulose and hemicellulose. However, lignin droplets on the surface of elephant grass and the high lignin content in reed straw limited their hydrolysis performances. High hydrolysis yield was obtained for reed straw after organosolv and alkali pretreatments via increasing cellulose content and removing lignin. However, the hydrolysis of elephant grass was only enhanced by organosolv pretreatment. Further study showed that the addition of bovine serum albumin (BSA) or thioredoxin with His- and S-Tags (Trx-His-S) improved the hydrolysis of alkali-pretreated elephant grass. In particular, Trx-His-S was first used as an additive in lignocellulose saccharification. Its structural and catalytic properties were supposed to be beneficial for enzymatic hydrolysis. Conclusions Elephant grass and reed straw could be used as feedstocks for bioconversion. Organosolv and alkali pretreatments improved their enzymatic sugar production; however, the increase in hydrolysis yield of pretreated elephant grass was not as effective as that of reed straw. During the hydrolysis of alkali-pretreated elephant grass, Trx-His-S performed well as additive, and its structural and catalytic capability was beneficial for enzymatic hydrolysis.

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Physico-chemical pretreatment and enzymatic hydrolysis of cotton stalk for ethanol production by Saccharomyces cerevisiae

Bioresource Technology ◽

10.1016/j.biortech.2017.07.123 ◽

2017 ◽

Vol 244 ◽

pp. 71-77 ◽

Cited By ~ 12

Author(s):

Anita Singh ◽

Somvir Bajar ◽

Narsi R. Bishnoi

Keyword(s):

Saccharomyces Cerevisiae ◽

Enzymatic Hydrolysis ◽

Ethanol Production ◽

Chemical Pretreatment ◽

Cotton Stalk ◽

Physico Chemical ◽

Hydrolysis Of

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Tryptic phosphopeptides from whole casein. II. Physicochemical properties related to the solubilization of calcium

Journal of Dairy Research ◽

10.1017/s0022029900028776 ◽

1989 ◽

Vol 56 (3) ◽

pp. 335-341 ◽

Cited By ~ 89

Author(s):

Rafael Berrocal ◽

Serge Chanton ◽

Marcel A. Juillerat ◽

Blaise Favillare ◽

Jean-Claude Scherz ◽

...

Keyword(s):

Binding Sites ◽

Calcium Phosphates ◽

Chemical Properties ◽

Sodium Caseinate ◽

Ph Values ◽

Physico Chemical ◽

Casein Phosphopeptides ◽

Hydrolysis Of ◽

Phosphate Solutions ◽

Tryptic Hydrolysis

SummaryCasein phosphopeptides (GPP) were produced by tryptic hydrolysis of sodium caseinate and further purified by precipitation and chromatography on QAE-Sephadex A-25. Their physico-chemical properties were compared with the properties of an enzymically dephosphorylated equivalent preparation (DPP). Binding of Ca2+ to the peptides was measured using a Ca selective electrode and was found to increase with pH and to show 1/1 stoicheiometry Ca/Porg in CPP at pH 6·5 a.nd 7·6. Klotz plots indicated equivalent binding sites at these two pH values, but some heterogeneity was seen at pH 3·5. In contrast, DPP did not bind significant amounts of Ca2+.CPP effectively inhibited the formation of insoluble calcium phosphates at different Ca/P ratios. The effective CPP concentration was 10 mg/1 and complete stability of calcium phosphate solutions was obtained at about 100 mg/1. This stabilizing effect was dependent on the presence of organic P.

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