Review
Biotechnology & Applied Microbiology
Yufeng Yuan, Bo Jiang, Hui Chen, Wenjuan Wu, Shufang Wu, Yongcan Jin, Huining Xiao
Summary: Enzymatic hydrolysis of lignocellulose for bioethanol production has great potential, but the presence of lignin inhibits the process. Pretreatment methods can remove lignin and improve enzymatic digestibility. Researchers are focusing on exploring the relationship between lignin structure and lignin-enzyme interactions to enhance saccharification efficiency.
BIOTECHNOLOGY FOR BIOFUELS
(2021)
Review
Agricultural Engineering
Jitendra Kumar, Himanshu, Hemansi, Amanjot Kaur, Aayush Mathur
Summary: Global interest in lignocellulosic biorefineries has increased due to sustainable technological advancements. However, enzymatic hydrolysis in biorefinery operations faces challenges that limit cost-effectiveness.
BIORESOURCE TECHNOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Hui Chen, Bo Jiang, Chunyang Zou, Zhichao Lou, Junlong Song, Wenjuan Wu, Yongcan Jin
Summary: In this study, the interaction between lignin and cellulase was investigated using a carbohydrate-binding module (CBM) functionalized atomic force microscope tip. The results showed that sulfonated lignin (SL) had the strongest adhesion force to CBM, while other lignin samples had weaker adhesion forces. It was found that the primary mechanism by which SL promoted hydrolysis was by reducing the nonproductive adsorption of substrate lignin onto cellulase. The study also proposed a competitive adsorption mechanism to explain the effective promotion of enzymatic hydrolysis by SL in lignin-containing substrates.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Agricultural Engineering
Xiaoxue Zhao, Caoxing Huang, Wenqian Lin, Bin Bian, Chenhuan Lai, Zhe Ling, Qiang Yong
Summary: This study investigated the adsorption mechanism and structure-activity relationship between lignin and different cellulase domains using fluorescence spectroscopy and SDS-PAGE. It was found that endo-cellulase 6B had a higher affinity to lignin fractions, which was positively correlated to molecular weight. The adsorption between lignin fractions and endo-cellulase 6B was mainly driven by van der Waals and electrostatic forces, while hydrophobic force drove the adsorption of lignin fractions to CBM4A. The results demonstrated the critical role of lignin's structure in its adsorption with various cellulase domains.
BIORESOURCE TECHNOLOGY
(2022)
Article
Green & Sustainable Science & Technology
Cheng Cai, Chaofeng Zhang, Ning Li, Huifang Liu, Jun Xie, Hongming Lou, Xuejun Pan, J. Y. Zhu, Feng Wang
Summary: Hydrolyzing lignocellulose and transforming it into chemicals and fuels is an essential aspect of biorefining. Previously, lignin was believed to inhibit the enzymatic hydrolysis of lignocellulosic substrates. However, recent research has shown that under specific conditions, lignin can actually increase the sugar yield and act as an activator/promoter of enzymatic hydrolysis. Furthermore, lignin-based carriers have been developed to reduce the load and cost of cellulases.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Agricultural Engineering
Mohan Li, Yufeng Yuan, Yangsu Zhu, Bo Jiang, Wenjuan Wu, Shufang Wu, Yongcan Jin
Summary: The addition of sulfomethylated lignins in enzymatic hydrolysis significantly improved substrate digestibility and sugar yield. Competitive adsorption between cellulase, substrate lignin, and SLs was suggested as a mechanism for the observed effects.
BIORESOURCE TECHNOLOGY
(2022)
Article
Materials Science, Paper & Wood
Florian Csarman, Claudia Gusenbauer, Lena Wohlschlager, Gijs van Erven, Mirjam A. Kabel, Johannes Konnerth, Antje Potthast, Roland Ludwig
Summary: This study investigates the binding of cellulolytic enzymes onto biopolymers. Results show that the removal of N-glycans does not significantly affect the activity or binding tendency, but a slightly higher tendency for non-productive binding is observed on surfaces modified with different lignin fractions.
Review
Biotechnology & Applied Microbiology
Yunzi Hu, Anshu Priya, Chao Chen, Cuiyi Liang, Wen Wang, Qiong Wang, Carol Sze Ki Lin, Wei Qi
Summary: Lignocellulosic biorefinery, as a potential strategy for sustainable production, faces challenges of low degradation efficiency and high enzyme dosage. This article provides a comprehensive review on this subject by discussing recent advances in substrate modification techniques, enzyme synergism mechanisms, and structure-activity interaction. Newly developed modeling and multi-omic analysis techniques for commercial enzyme preparations are introduced, offering possible avenues for achieving economic viability of lignocellulose bioconversion.
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
(2023)
Review
Biochemistry & Molecular Biology
Mohan Li, Bo Jiang, Wenjuan Wu, Shufang Wu, Yiqin Yang, Junlong Song, Mehraj Ahmad, Yongcan Jin
Summary: This article discusses optimization strategies for enzymatic hydrolysis using lignin, including lignin structural modification, enzyme engineering, and different additives. Water-soluble lignin can enhance the rate of enzymatic digestibility, but the mechanism of lignin-enzyme interaction remains unclear.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Biochemistry & Molecular Biology
Topi Haataja, Japheth E. Gado, Anu Nutt, Nolan T. Anderson, Mikael Nilsson, Majid Haddad Momeni, Roland Isaksson, Priit Valjamae, Gunnar Johansson, Christina M. Payne, Jerry Stahlberg
Summary: In this study, the hydrolysis characteristics of two model enzymes in the CBH family 7 were examined using enzyme kinetics, crystallographic structure determination, molecular dynamics simulations, and fluorometric binding studies. The results revealed that the strength of non-productive binding is a key determinant for the activity characteristics of these enzymes on different substrates.
Article
Engineering, Chemical
Hongyuan Wang, Lihong Zhao, Junli Ren, Beihai He
Summary: This study investigates the structural changes of alkali lignin induced by ozonation and examines the effect and mechanism of ozone-treated alkali lignin on Avicel enzymatic hydrolysis. The results show that ozone pretreatment increases the carboxyl and/or aldehyde groups and the negative zeta potential of alkali lignin, resulting in enhanced electrostatic repulsion with cellulase. The hydrophobic interaction is diminished, and the binding strength between cellulase and ozone pretreated alkali lignin is significantly lower than that of alkali lignin. The research aims to reduce non-productive adsorption and provides a green and feasible pretreatment process for the enzymatic hydrolysis of lignocellulose.
Article
Biochemistry & Molecular Biology
Yajing Liu, Jian Wang, Chengling Bao, Bing Dong, Yunhe Cao
Summary: This study investigated a novel endo-xylanase with potential applications in biomass hydrolysis. It was found that the enzyme showed high activity in degrading xylan from various biomass sources and synergized with cellulase to improve hydrolysis efficiency. The study demonstrated the potential of this enzyme in biofuel production.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Review
Biotechnology & Applied Microbiology
Qicheng Shi, Ahmed M. Abdel-Hamid, Zhanying Sun, Yanfen Cheng, Tao Tu, Isaac Cann, Bin Yao, Weiyun Zhu
Summary: The microbial decomposition and utilization of lignocellulosic biomass in plant tissues are driven by carbohydrate active enzymes (CAZymes), including carbohydrate-binding modules (CBMs), which assist in the recognition and depolymerization of complex substrates. This review provides a taxonomy and biological properties of CBMs, outlines their molecular mechanisms in enzymatic hydrolysis, and discusses their potential in industrial applications such as enzymatic pretreatment of lignocellulose.
BIOTECHNOLOGY ADVANCES
(2023)
Article
Agricultural Engineering
Qiang Xiong, Jie Qiao, Minghui Wang, Shuang Li, Xiujuan Li
Summary: This study investigated the effects of carboxylated and quaternized lignin (CQL) and hydroxymethylated lignin (HML) on enzymatic hydrolysis efficiency (EHE) of p-toluenesulfonic acid treated corn stover (PCS). The results showed that CQL enhanced EHE by forming CQL-I3-GL complexes with lower binding free energy, while HML decreased EHE due to overlapping binding sites with the carbohydrate binding domain of I3-GL, resulting in decreased enzyme activity. This research helps in understanding the impact of modified lignins on EHE and cellulase adsorption.
BIORESOURCE TECHNOLOGY
(2021)
Article
Forestry
Malik Owais Ullah Awan, Akhtar Iqbal, Muhammad Imtiaz Rashid, Usman Irshad, Farhan Hafeez, Farid Ullah, Muhammad Irshad, Gabrijel Ondrasek, Ivan Mustac, Rashid Nazir
Summary: The diversified Galiyat forests in the Lower Himalayas possess a potential source of lignocellulose degrading bacteria, with cellulose degraders, xylanase producers, and laccase producers identified among the isolates. These bacteria showed diversity in terms of their taxonomic classification and their ability to degrade different lignocellulosic components.
Article
Materials Science, Paper & Wood
Sathish Kumar Mudedla, Maisa Vuorte, Elias Veijola, Kaisa Marjamaa, Anu Koivula, Markus B. Linder, Suvi Arola, Maria Sammalkorpi
Summary: Enzymatic cleavage of glycocidic bonds is an important method to refine lignocellulosic biomass. This study explored the effects of oxidation defects on the structure and water interactions of cellulose {100} surface, showing that even single oxidations reduce connections within cellulose crystal and enhance water interactions. The findings also revealed different levels of soluble glucose fragments released during LPMO enzyme treatment on different cellulose species, indicating the significance of understanding enzymatic oxidation effects on cellulose nanocrystals and cleavage of soluble products.
Article
Agricultural Engineering
Sara Ceccherini, Jenni Rahikainen, Kaisa Marjamaa, Daisuke Sawada, Stina Gronqvist, Thad Maloney
Summary: The study compares the effects of endoglucanase and lytic polysaccharide monooxygenase on bleached softwood Kraft pulp, finding that a combination of enzymes results in the largest changes, improving properties such as fibrillation and fines content.
INDUSTRIAL CROPS AND PRODUCTS
(2021)
Article
Chemistry, Multidisciplinary
Riin Kont, Ville Pihlajaniemi, Klaus Niemela, Silja Kuusk, Kaisa Marjamaa, Priit Valjamae
Summary: This study evaluated the dynamics of H2O2 in the liquid fractions of different biomasses using an LPMO-based detection tool, revealing that H2O2 acts as an intermediate in the oxidation of compounds in the liquid fractions, with its formation rate higher than its accumulation rate. The liquid fractions of different biomasses have varying effects on the formation of H2O2 and the enzymatic degradation of cellulose.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2021)
Article
Materials Science, Paper & Wood
Anna Kalliola, Petteri Kangas, Iris Winberg, Tapio Vehmas, Hanna Kyllonen, Juha Heikkinen, Outi Poukka, Katariina Kemppainen, Pauliina Sjogard, Lauri Pehu-Lehtonen, Tiina Liitia
Summary: This paper presents a concept of alkali-O-2 oxidation process for producing lignin dispersants in a feasible manner at a kraft pulp mill. The process uses O-2 gas to increase the anionic charge of lignin, resulting in oxidised lignin that can be used as a concrete plasticiser or versatile dispersant. The integrated process simplifies lignin recovery, reduces the need for fresh alkali, and enables the recirculation of sodium and sulphur back to the chemical cycle.
NORDIC PULP & PAPER RESEARCH JOURNAL
(2022)
Article
Energy & Fuels
Anna S. Borisova, Ville Pihlajaniemi, Riin Kont, Klaus Niemela, Taru Koitto, Atte Mikkelson, Priit Valjamae, Kristiina Kruus, Kaisa Marjamaa
Summary: This study investigates the inhibitory effect of soluble phenolics in hydrothermal pretreatment liquor on Trichoderma reesei enzymes. Cellobiohydrolases were found to be the most sensitive to phenolics inhibition, while xylanases and endoglucanases could mitigate the inhibitory effect. The addition of lytic polysaccharide monooxygenase was found to relieve the negative effect of phenolics, and the hydrolytic activity of commercial enzyme cocktail Cellic Ctec2 was enhanced in the presence of low concentrations of phenolics.
BIOMASS CONVERSION AND BIOREFINERY
(2022)
Article
Materials Science, Paper & Wood
Kaisa Marjamaa, Jenni Rahikainen, Marika Karjalainen, Natalia Maiorova, Ulla Holopainen-Mantila, Matthieu Molinier, Nina Aro, Heli Nygren, Atte Mikkelson, Anu Koivula, Kristiina Kruus
Summary: This study investigated the parameters affecting the efficiency of LPMO in oxidative modification of cotton linters and softwood kraft fibres. The results showed that temperature and pH affected the stability and efficacy of the enzyme. The oxidative enzymatic treatment facilitated fibre dissolution and degradation of fibre surface structures, preventing swelling.
Article
Materials Science, Paper & Wood
Minna Vikman, Olesya Fearon, Anna Kalliola
Summary: Lignin can be converted into a water-soluble form through alkali-O-2 oxidation, increasing its biodegradability. The oxidized lignins exhibited higher biodegradation in soil and aquatic environments compared to reference lignins. This improvement is due to the altered chemical structure of the oxidized lignin, which makes it more accessible to microbial degradation.
Article
Green & Sustainable Science & Technology
Emanuela Calcio Gaudino, Giorgio Grillo, Silvia Tabasso, Livio Stevanato, Giancarlo Cravotto, Kaisa Marjamaa, Ville Pihlajaniemi, Anu Koivula, Nina Aro, Jaana Uusitalo, Jarmo Ropponen, Lauri Kuutti, Pauliina Kivinen, Heimo Kanerva, Alexander Arshanitsa, Lilija Jashina, Vilhelmine Jurkjane, Anna Andersone, Thomas Dreyer, Gerhard Schories
Summary: This paper reports the dominant physical effects of ultrasound (US) pretreatment on improving delignification of wheat straw. The study demonstrates that ultrasound pretreatment can effectively increase the yield of soluble sugars by making the cellulose more susceptible to enzymatic hydrolysis. The results show that ultrasound pretreatment has advantages over steam explosion pretreatment in terms of environmental impact and cost-benefit analysis.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Green & Sustainable Science & Technology
Neethi Rajagopalan, Iris Winberg, Olesya Fearon, Giuseppe Cardellini, Tiina Liitia, Anna Kalliola
Summary: Bio-based products can reduce dependency on fossil-based raw materials and contribute to sustainability goals. The introduction of the alkali-O-2 oxidation process for producing lignin dispersants shows promising results in terms of environmental benefits compared to synthetic products. However, the kraft pulping process still has negative impacts on the environment.
Article
Materials Science, Paper & Wood
Elisa Sponla, Jenni Rahikainen, Antje Potthast, Stina Gronqvist
Summary: The sustainability of regenerated cellulosic fibres can be improved by using paper grade pulp instead of dissolving pulp, but adjusting the molar mass distribution (MMD) is necessary for good solubility and spinnability. Enzymatic treatments were used to adjust the MMD of softwood and eucalyptus kraft pulps, and it was found that eucalyptus pulp required a higher dose of endoglucanase compared to softwood pulp. Combining xylanase with endoglucanase reduced the required endoglucanase dose for eucalyptus pulp, indicating that xylan inhibited the enzymatic treatment. The different processabilities of the pulps were attributed to differences in cellulose accessibility and hemicellulose composition and localization.
Article
Materials Science, Paper & Wood
Elisa Sponla, Simo Hannula, Taina Kamppuri, Ulla Holopainen-Mantila, Irina Sulaeva, Antje Potthast, Ali Harlin, Stina Gronqvist, Jenni Rahikainen
Summary: In this study, regenerated fibers were spun from hemicellulose-rich pulps using a superbase ionic liquid, and it was found that pulp pretreatment was critical for achieving good mechanical properties in the regenerated fibers.
Article
Agricultural Engineering
Hanna Kyllonen, Anna S. Borisova, Juha Heikkinen, Petri Kilpelainen, Jenni Rahikainen, Christiane Laine
Summary: This study aimed to refine and concentrate tannins extracted from softwood bark using membrane filtration, and enzymatic hydrolysis was used to separate bark sugars from bark phenols. The results showed that nanofiltration at alkaline pH successfully concentrated bark phenols, and enzymatically liberated sugars were effectively permeated through the membrane.
INDUSTRIAL CROPS AND PRODUCTS
(2023)
Article
Biotechnology & Applied Microbiology
Miriam Kellock, Jenni Rahikainen, Anna S. Borisova, Sanni Voutilainen, Anu Koivula, Kristiina Kruus, Kaisa Marjamaa
Summary: This study investigated the effect of enzymatically isolated lignin on the hydrolysis of xylan by four glycoside hydrolase family 11 xylanases. It was found that lignin isolated from steam pretreated spruce decreased the hydrolysis yields of xylan, and the degree of inhibition varied among different xylanases. The thermostable xylanases exhibited higher tolerance to lignin, and the presence of N-glycans in the catalytic domain of Xyl40 increased its lignin tolerance. The findings suggest that the thermal stability of xylanases and the structural features contribute to their activity on the lignin surface.
BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS
(2022)
Article
Biotechnology & Applied Microbiology
Thore Bach Thomsen, Tobias S. Radmer, Anne S. Meyer
Summary: Plastic pollution, particularly from PET, is a significant environmental challenge. This study investigates the enzyme kinetics of PET degradation and finds that the degree of crystallinity (X-C) has a substantial impact on the enzymatic reaction rate. The mobile amorphous fraction (X-MAF) is a better descriptor for the rate of enzymatic degradation. The longer lag phase observed with increased X-C is proposed to be due to increased substrate entanglement density and unproductive enzyme binding to the crystalline regions of PET.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Purna Bahadur Poudel, Dipesh Dhakal, Jong Cheol Lee, Jae Kyung Sohng
Summary: Methylation plays important roles in various biological processes, and this study characterized the function of ThnM3 in regioselective modifications of 1,8-dihydroxynaphthalene.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Feng Song, Ivan Birukou, Mark Bednarcik, Scott Young
Summary: In this study, a highly sensitive and specific method using ultra performance liquid chromatography (UPLC) was developed to measure the enzymatic activity of APH4 in plants. The method exhibited good precision and accuracy, and was validated for use with samples from different sources.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Yuan Rao, Wei Zhuang, Jinle Liu, Ting Tang, Zhi Wang, Hanjie Ying
Summary: This study describes a mild and versatile strategy to immobilize glucose oxidase (GOD) on carboxyl-activated metal-organic framework (MOF) through DNA-directed immobilization technology. The immobilized GOD showed enhanced stability and catalytic activity, making it a potential candidate for applications in biocatalysis and biotechnology.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Julen Ordenana Manso, Martin B. Nielsen, Eva Balaguer Moya, Juliana P. Sandri, Celina K. Yamakawa, Solange I. Mussatto
Summary: This study focuses on the development of an enzymatic cocktail for the conversion of corn fiber into monosaccharides. The results reveal that the recalcitrance and unique chemical composition of corn fiber require a tailored enzymatic cocktail for degradation, and attention should also be given to the pretreatment step.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Cuixia Zhou, Guangcheng Yang, Panpan Meng, Weishuai Qin, Yanyan Li, Zhenxian Lin, Wei Hui, Huitu Zhang, Fuping Lu
Summary: Bacillus licheniformis 2709 is an important industrial producer of alkaline protease (AprE), and this study identified the UP elements of the aprE gene and demonstrated the lack of significant effect of CggR, FruR, and YhcZ transcription factors on aprE expression. Enhanced aprE expression and enzyme activity were achieved by deleting a negative regulatory factor binding site in the genome. These findings provide valuable insights into the high-level production of proteins in other Bacillus species.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Xinqi Xu, Tianheng Chen, Lian Xu, Juan Lin
Summary: In this study, laccase was immobilized on modified magnetic nanoparticles, improving the enzyme's thermostability and efficiency for polymerization of phenols.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Handan Ustukarci, Gul Ozyilmaz, Ali Tuncay Ozyilmaz
Summary: A biofilm layer called biofouling is formed over time by organic molecules and microorganisms on solid surfaces immersed in a liquid medium. This study focused on the antifouling performance of polyaniline (PANI) and investigated the immobilization of hydrolytic enzymes in PANI coatings. The results showed that the alpha-amylase-containing film exhibited the highest antifouling activity. Surface properties and biofilm composition were analyzed to support these findings.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)
Article
Biotechnology & Applied Microbiology
Mariana Ortiz-Sanchez, Juan Camilo Solarte-Toro, Pablo Jose Inocencio-Garcia, Carlos Ariel Cardona Alzate
Summary: This study evaluated the sustainability of biorefineries using orange peel as a raw material. By applying the concept of biorefineries and experimental data, it was found that steam distillation and polyphenolic compound extraction can improve the process performance, resulting in higher yields of different products. The integrated utilization of orange peel in biorefineries showed a high sustainability index.
ENZYME AND MICROBIAL TECHNOLOGY
(2024)