Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
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Recent antibacterial agents from biomass derivatives: Characteristics and applications
Nissa Nurfajrin Solihat, Alif Faturahman Hidayat, R. A. Ilyas, Senthil Muthu Kumar Thiagamani, Nur Izyan Wan Azeele, Fahriya Puspita Sari, Maya Ismayati, Mohammad Irfan Bakshi, Zaharaddeen N. Garba, M. Hazwan Hussin, Witta Kartika Restu, Wasrin Syafii, Harits Atika Ariyanta, Widya Fatriasari
 doi: 10.1016/j.jobab.2024.02.002
[Abstract](0) [PDF 3807KB](0)
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Enhancing awareness of personal cleanliness and antibacterial resistance has intensified the antibacterial substance request on consumable products. Antibacterial agents that have been commercialized nowadays are produced from inorganic and non-renewable substances. This provides several drawbacks, particularly against health and environmental issues. Therefore, many scientists work on substituting fossil-fuel-based antibacterial agents with natural ones such as from biomass. Biomass derivatives, natural abundances of biopolymers in the world, amount to major compounds including polysaccharides (cellulose, hemicellulose, and chitosan) and polyphenol (tannin and lignin) substances which are capable to combat the growth of Gram-positive bacteria and Gram-negative bacteria. To date, no report focuses on a deep understanding of antibacterial properties derived from biomass and the internal and external factors effects. This work provides that gap because comprehensive knowledge is necessary before applying biomass to the products. The potency of biomass derivatives as antibacterial additives is also summarized. Basic knowledge of antibacterial characteristics to the application in products is highlighted in this review. Besides, the discussion about challenges and future perspectives is also delivered.
Biorenewable materials for water remediation: The central role of cellulose in achieving sustainability
Kirti Mishra, Samarjeet Singh Siwal, Thandiwe Sithole, Nirankar Singh, Phil Hart, Vijay Kumar Thakur
 doi: 10.1016/j.jobab.2023.12.002
[Abstract](10) [PDF 5889KB](0)
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As the population increases and manufacturing grows, greenhouse gas and other harmful emissions increase. Contaminated with chemicals such as dyes, pesticides, pharmaceuticals, oil, heavy metals or radionuclides, wastewater purification has become an urgent issue. Various technologies exist that can remove these contaminants from wastewater sources, but they often demand high energy and/or high cost, and in some cases produce contaminant laden sludge that requires safe disposal. The need for methods which are less capital intensive, less operationally costly and more environmentally friendly is suggested. Cellulose-based materials have emerged as promising candidates for wastewater treatment due to their renewability, low cost, biodegradability, hydrophilicity, and antimicrobial property. In this review article, we focussed on developing sustainable and biodegradable cellulose-based materials for wastewater treatment. This article deals with cellulose-based materials’ scope and their conversion into valuable products like hydrogel, aerogel, cellulose composites, and nanocellulose. The cellulose-based materials have no harmful environmental impact and are plentiful. The modified cellulose-based materials applying as membrane, adsorbent, sorbent, and beads to purify the wastewater were discussed. Finally, the challenges and future prospects of cellulose-based materials for wastewater treatment were considered, emphasizing their potential to be sustainable and eco-friendly alternatives to traditional materials used in wastewater treatment.
Study on the Mechanism and Law of Temperature, Humidity and Moisture Content on the Mechanical Properties of Molded Fiber Products
Zhiqiang Fua, Tong Zhao, Hu Wang, Jingyi Wei, Haozhe Liu, Liying Duan, Yan Wang, Ruixiang Yan
 doi: 10.1016/j.jobab.2024.04.003
[Abstract](0) [PDF 3563KB](0)
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The change of temperature, humidity and moisture content (MC) will lead to the change of mechanical properties of molded fiber products (MFP). However, it is difficult to decouple the effects of temperature, humidity and MC on the mechanical properties of MFP, and predict the mechanical properties of MFP during the use. In this study, the laws and mechanism of mechanical properties of MFP with ambient temperature, humidity and MC were studied. The results showed that the direct effect of temperature (20−70 ℃) on mechanical properties of MFP was insignificant, and the mechanical properties of MFP were mainly changed by MC. The MC was related to ambient temperature and humidity, and the relationship between the three could be described by the modified Guggenheim-Anderson-de Boer (GAB) model (20−70 ℃ and 30 %−90 % relative humidity). With the increase of MC, the elastic modulus and fracture strain was increased and decreased linearly, the yield strength and failure strength were presented GaussAmp laws, and the failure strain was presented asymptotic regressed distribution law. Two fracture modes of MFP, brittle fracture and ductile fracture, were revealed by the scanning electron microscopy of the mesoscopic fiber structure of sugarcane bagasse molded fiber products. The mathematical models and the changes of fiber structure were verified by wheat straw molded fiber products and waste paper molded fiber products. This study was contributed to understand the effects and mechanism of the change of temperature, humidity and MC on the mechanical properties of MFP.
Bacterial nanocellulose assembly into super-strong and humidity-responsive macrofibers
Yadong Zhao, Zheng Yang, Rusen Zhou, Bin Zheng, Meiling Chen, Fei Liu, Wenhua Miao, Renwu Zhou, Patrick Cullen, Zhenhai Xia, Liming Dai, Kostya (Ken) Ostrikov
 doi: 10.1016/j.jobab.2024.03.005
[Abstract](0) [PDF 2776KB](0)
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Cellulose macrofibers (MFs) are gaining increasing interest as natural and biodegradable alternatives to fossil-derived polymers for both structural and functional applications. However, simultaneously achieving their exceptional mechanical performance and desired functionality is challenging and requires complex processing. Here, we reported a one-step approach using a tension-assisted twisting (TAT) technique for MF fabrication from bacterial cellulose (BC). The TAT stretches and aligns BC nanofibers pre-arranged in hydrogel tubes to form MFs with compactly assembled structures and enhanced hydrogen bonding among neighboring nanofibers. The as-prepared BC MFs exhibited a very high tensile strength of 1057 MPa and exceptional lifting capacity (over 340000 when normalized by their own weight). Moreover, due to the volume expansion of BC nanofibers upon water exposure, BC MFs quickly harvested energy from environmental moisture to untwist the bundled networks, thus generating a torsional spinning with a peak rotation speed of 884 r/(min·m). The demonstrated rapid and intense actuation response makes the MFs ideal candidates for diverse humidity-response-based applications beyond advanced actuators, remote rain indicators, intelligent switches, and smart curtains.
Evaluating mechanism of banana pseudo-stem retting using seawater: A cost-effective surface pre-treatment approach
Prince Hotor, Ahmed H. Hassanin, Osbert Akatwijuka, Mohamed A.H. Gepreel, Mitsuo Yamamoto, Yukie Saito, Ahmed Abdel-Mawgood
 doi: 10.1016/j.jobab.2024.04.002
[Abstract](0) [PDF 2055KB](0)
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Retting has been employed to extract natural fibers from agricultural wastes as a biological and cost-effective approach for centuries. With its global abundance, banana pseudo-stem is a promising agro-waste for lignocellulosic fiber extraction. In this study, fibers were extracted from the pseudo-stems after being pre-treated under four conditions using seawater at room temperature for up to 35 d Bacterial isolation from the fresh seawater sample and screening for ligninolytic ability were conducted. Bacterial load as well as laccase and manganese peroxidase enzyme activity profile assay during the retting duration were analyzed. Fourier transform infrared (FT-IR) and X-day diffraction (XRD) analyses were also examined for both pre-treated and untreated extracted fibers. The results shows that six out of the eight bacterial isolates had the ability to degrade lignin. The treatments (Raw stem + Raw seawater) and (Autoclaved stem + Raw seawater) recorded the highest viable bacterial load of 9.24 × 102 and 4.46 × 102 CFU, respectively, on the 14th day of the retting process. Additionally, the highest laccase and manganese peroxidase enzymes activity was recorded for (Raw stem + Raw seawater) and (Autoclaved stem + Raw seawater) treatments in the second to the third week. The FT-IR spectra of the pre-treated fibers revealed relative reductions in peaks attributed to polysaccharides and other amorphous substances for all retting conditions. The XRD diffractogram revealed that the crystallinity index (CI) of pre-treated fibers increased in all seawater retting treatment conditions. However, the CI for fibers pre-treated under enzymatic conditions were enhanced even after five weeks. Sequence analysis for selected bacterial isolates showed homology to sequences of Bacillus velezensis, Shewanella sp. L8–5, and Citrobacter amalonaticus and Bacillus subtilis j8 strain. From these findings, it was suggested that physical, biological, and chemical actions were collectively involved in the seawater retting process of banana pseudo-stems.
Exploring hemp seed hull biomass for an integrated C-5 biorefinery: Xylose and activated carbon
Sreesha Malayil, Luke Loughran, Frederik Mendoza Ulken, Jagannadh Satyavolu
 doi: 10.1016/j.jobab.2024.01.002
[Abstract](33) [PDF 2396KB](3)
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Large quantities of hemp hulls can be completely utilized for creation of value-added products (cost effective biofuels and biochemicals) through a biorefinery approach. A sustainable approach in making xylose, a low calorie sweetener and high surface area activated carbons (AC) for super capacitors, attracts interest. The AC when leveraged as a co-product from biorefinery process makes it more cost effective and, in this paper, we discuss the production of xylose and AC from hemp seed hull with methane sulphonic acid (MSA) hydrolysis. Xylose recovery with MSA hydrolysis was 25.15 g/L when compared to the traditional sulphuric acid (SA) hydrolysis of 19.96 g/L at the same acid loading of 1.8 %. The scanning electron microscope (SEM) images and Fourier transform infrared (FT-IR) spectra indicate partial delignification along with hemicellulose hydrolysis responsible for high xylose recovery. Post hydrolysis fibers were KOH activated and carbonized to make AC. The MSA hydrolyzed and KOH activated fiber produced pure, fluffier and finer particle AC with a drastic increase in surface area 1 452 m2/g when compared to SA hydrolyzed of 977 m2/g. These results indicate the potential of MSA in dilute acid hydrolysis of biomass for xylose recovery and production of high surface area activated carbon. From a production standpoint this can lead to increased use of sustainable low-cost agricultural biomass for making high surface area AC as components in supercapacitors.
Constructing Osteo-Inductive Bio-Ink for 3D Printing Through Hybridization of Gelatin with Maleic Acid Modified Bacterial Cellulose by Regulating Addition Volumes of Maleic Acid Solution
Xucai Wang, Dengxian Wu, Wei Liao, Yaxuan Liu, Wenhui Pei, Jixian Wang, Jiayu Gu, Peng Wangb, Kai Lane, Caoxing Huanga
 doi: 10.1016/j.jobab.2024.04.001
[Abstract](0) [PDF 3481KB](0)
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Bacterial cellulose (BC) is an exopolysaccharide with unique properties that has been applied in various fields. However, the dense and intertwined nature of BC fibers limits its use in certain applications, including 3D printing scaffolds for bone regeneration. In this work, a controllable BC-based bio-ink for 3D printing was successfully prepared by modifying the neat BC through maleic acid (MA) treatment, aiming to promote bone tissue regeneration. To achieve homogeneous BC dispersions while preserving its crystalline and chemical properties, BC was modified by MA solution (60 %, w/V) with solid-liquid ratio from 1꞉5 to 1꞉50 (w/V) to obtain MABC dispersions. The analysis results from microstructure, chemical group, crystallinity, and wettability indicated that the BC/MA solution with ratio of 1꞉30 demonstrated the best pre-treatment performance to obtain MA-BC. Subsequently, by combining MA-BC with gelatin, we successfully formulated MA-BC-GEL gels with favorable rheological properties and compression modulus, which can be used as promising bio-inks for 3D bioprinting applications. In vitro tests demonstrated 1꞉30 MA-BC possessed excellent biocompatibility, a significant ability to express the alkaline phosphatase gene and osteogenic-related genes, and facilitated the formation of mineralized nodules. The utilization of this novel bio-ink in scaffold preparation for bone regeneration highlights the promising application of modified BC in bone tissue engineering field.
Selective activation of C-C bonds in lignin model compounds and lignin for production of value-added chemicals
Long Cheng, Shanyong Wang, Hailong Lu, Jun Ye, Junming Xu, Kui Wang, Jianchun Jiang
 doi: 10.1016/j.jobab.2024.02.001
[Abstract](0) [PDF 10425KB](0)
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Lignin is a rich renewable aromatic resource that can produce high-value-added chemicals. Lignin is regarded as one of the three major components of lignocellulosic biomass, which is composed of phenylpropane units connected by C–O bond and C–C bond. The cleavage of two chemical bonds is the main catalytic pathway in the production of chemicals and fuels from lignin. Although the cleavage of C–O converts lignin into valuable aromatic compounds and renewable carbon sources, selective depolymerization for C–C bonds is an important method to increase the yield of aromatic monomers. Therefore, in this review, we summarized the latest research trends on C–C bond selective cleavage in lignin and lignin model compounds, focusing on various catalytic systems, including hydrogenolysis, oxidate, photocatalysis, and electrocatalysis. By analyzing the current status of C–C bond breakage, the core issues and challenges related to this process and the expectations for future research were emphasized.
Starting materials, processes and characteristics of bio-based foams: A review
Xiaohan Wang, Jinwon Jang, Yanqun Su, Jingang Liu, Hongjie Zhang, Zhibin He, Yonghao Ni
 doi: 10.1016/j.jobab.2024.01.004
[Abstract](28) [PDF 1764KB](2)
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Biofoam products have attracted considerable attention lately because there is a growing demand for green/sustainable products. To this end, various biobased foams have either been developed or are currently in development, e.g., bio-based polyurethanes (PUs), polylactic acid (PLA), starch, and polyhydroxyalkanotates (PHAs). Indeed, significant progress has been made; however, challenges still persist, for example, biobased foam products have poor processability, inferior compatibility, thermal and strength properties. In this review, we focus on five biofoam products: namely bio-based PUs, PLA, starch, PHAs, and cellulose biofoam products, along with their properties and performance, as well as their manufacturing processes. Further efforts are still needed to unlock the full potential of these bio-based products and meet the goal of complementing and gradually replacing some of their fossil-based counterparts. Finally, the challenges, as well as arising opportunities of future research directions are discussed.
A Process Insight into Production of Ethyl Levulinate via A Stepwise Fractionation
Yan Ma, Hongxiao Wang, Ziyang Wu, Weihong Tan, Guodong Feng, Jianchun Jiang
 doi: 10.1016/j.jobab.2023.11.001
[Abstract](33) [PDF 2535KB](1)
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Ethyl levulinate (EL) is a key biomass-derived compounds due to its socio-economic benefits for the synthesis of commodity chemicals. Herein, we proposed an efficient one-step bamboo conversion to EL in ethanol, and a novel stepwise fractionation to purify EL and lignocellulose degradation products. A proton acid, due to its high catalytic efficiency, yielded 26.65% EL in 120 min at 200 °C. The productions of ethyl glucoside and 5-ethoxymethylfurfural were analyzed in terms of by-products formation. To the best of our knowledge, there is no single report on catalyst for one step synthesis of EL directly from bamboo, as well as a stepwise fractionation to purify EL. Due to similar physiochemical properties in each fraction, the platform molecules could broaden a new paradigm of bamboo biomass utilization for renewable energy and value-added biochemicals. In addition, glucose, ethyl glucoside, corn starch, and microcrystalline cellulose were also investigated as substrates, so that the reaction intermediates of this one-pot procedure were identified and a possible reaction mechanism was proposed.

Beyond Cotton and Polyester: An Evaluation of Emerging Feedstocks and Conversion Methods for the Future of Fashion Industry
Ryen M. Frazier, Keren A. Vivas, Ivana Azuaje, Ramon Vera, Alonzo Pifano, Naycari Forfora, Hasan Jameel, Ericka Ford, Joel J. Pawlak, Richard Venditti, Ronalds Gonzalez
 doi: 10.1016/j.jobab.2024.01.001
[Abstract](22) [PDF 2643KB](0)
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As the global population grows, the demand for textiles is increasing rapidly. However, this puts immense pressure on manufacturers to produce more fiber. While synthetic fibers can be produced cheaply, they have a negative impact on the environment. On the other hand, fibers from wool, sisal, fique, wood pulp (viscose), and man-made cellulose fibers (MMCFs) from cotton cannot alone meet the growing fiber demand without major stresses on land, water, and existing markets using these materials. With a greater emphasis on transparency and circular economy practices, there is a need to consider natural non-wood alternative sources for MMCFs to supplement other fiber types. However, introducing new feedstocks with different compositions may require different biomass conversion methods. Therefore, based on existing work, this review addresses the technical feasibility of various alternative feedstocks for conversion to textile-grade fibers. First, alternative feedstocks are introduced, and then conventional (dissolving pulp) and emerging (fibrillated cellulose and recycled material) conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of cellulose. It is important to note that for alternative feedstocks to be adopted on a meaningful scale, high biomass availability and proximity of conversion facilities are critical factors. In North America, soybean, wheat, rice, sorghum, and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods (pre-hydrolysis kraft, acid sulfite, soda, SO2-ethanol-water, and potassium hydroxide) or by emerging cellulose fibrillation methods. While dissolving pulp conversion is well-established, fibrillated cellulose methods could be beneficial from cost, efficiency, and environmental perspectives. Thus, the authors strongly encourage more work in this growing research area. However, conducting thorough cost and sustainability assessments is important to determine the best feedstock and technology combinations.

Nucleophilic Amino Acids as a Renewable Alternative to Petrochemically-Derived Amines in Glycerol Epoxy Resins
Yunyi Liang, Yonghong Luo, Yingji Wu, Xiaona Li, Quyet Van Le, Jianzhang Li, Changlei Xia
 doi: 10.1016/j.jobab.2024.01.003
[Abstract](21) [PDF 2373KB](0)
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The standard epoxy resin curing agents revealed are from unsustainable petroleum-based sources, which produce poisonous exhaust when cured. Amino acids, a bio-based epoxy curing agent with amino and carboxyl groups, are another potential curing agent. Water-soluble epoxy resins cured with lysine (Lys), glutamic acid (Glu), leucine (Leu), and serine (Ser) as amino acids were investigated. The results showed that the water-soluble epoxy resin (glycerol epoxy resins, GER) was cured with Lys and Glu after reacting. Fourier transform infrared (FT-IR) spectroscopic analysis of the GER-Lys showed that the amino and carboxyl groups of Lys primarily reacted with the epoxy groups of GER. The elongation at break of Lys-cured GER (GER-Lys) cured at 70 ℃ with a molar ratio of 1꞉0.75 was 75.32%. The fact that elongations at break of GER-Lys (79.43%) were higher than those of GER-Glu (17.33%), respectively supports the decrease of crosslinking density by the amino acid-cured GER reaction. The potential of Lys and Glu alternatives for petrochemical amines is demonstrated and provides promising opportunities for industrial application.

Effect of various aromatic compounds with different functional groups on enzymatic hydrolysis of microcrystalline cellulose and alkaline pretreated wheat straw
Yufeng Yuan, Xinyu Guo, Bo Jiang, Wenjuan Wu, Tingwei Zhang, Michael Sweeney, Mehraj Ahmad, Yongcan Jin
 doi: 10.1016/j.jobab.2023.12.006
[Abstract](20) [PDF 2401KB](1)
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Low molecular aromatic compounds are detrimental to the enzymatic hydrolysis of lignocellulose. However, the specific role of their functional groups remains unclear. Here, a series of nine aromatic compounds as additives were tested to understand their effect on the hydrolysis yield of microcrystalline cellulose (MCC) and alkaline pretreated wheat straw. Based on the results, the inhibition of aldehyde groups on MCC was greater than that of carboxyl groups, whereas for the alkaline pretreated wheat straw case, the inhibitory effect of aldehyde groups was lower than that of carboxyl groups. Increased methoxyl groups of aromatic compounds reduced the inhibitory effect on enzymatic hydrolysis of both substrates. Stronger inhibition of aromatic compounds on MCC hydrolysis was detected in comparison with the alkaline pretreated wheat straw, indicating that the substrate lignin can offset the inhibition to a certain extent. Among all aromatic compounds, syringaldehyde with one aldehyde group and two methoxyl groups improved the glucan conversion of the alkaline pretreated wheat straw.

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Commentary
Cellulose sub-nanometric ribbons: A new generation of nanocellulose and platform for biomaterials
Shaomin Kang, Yang Zhao, Junlong Song, Huining Xiao
2024, 9(1): 1-2.   doi: 10.1016/j.jobab.2023.09.002
[Abstract](33) [PDF 250KB](4)
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Review
Nanotechnology approaches towards biodeterioration-resistant wood: A review
Ayyoob Arpanaei, Qiliang Fu, Tripti Singh
2024, 9(1): 3-26.   doi: 10.1016/j.jobab.2023.09.001
[Abstract](36) [PDF 4969KB](2)
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Wood can be a suitable alternative to energy-intensive materials in various applications. Nevertheless, its susceptibility to weathering and decay has significantly hindered the broad adoption of the most commercially significant wood species. While current solutions do tackle certain challenges, they often come with disadvantages like high costs, environmental risks, and/or inefficiencies. Nanotechnology-based methods can be employed to mitigate these weaknesses and create durable, sustainable wood materials. In this review, we delve into cutting-edge advancements in the development of biodeterioration-resistant wood through innovative nanotechnology approaches. These methods usually involve the application of nanomaterials, either possessing biocidal properties or serving as carriers for biocides. We systematically describe these approaches and compare them to conventional wood modification methods. Additionally, this review provides a brief overview of the prevalent biodeteriorating organisms and their mechanisms of action, which notably impact the development and choice of a suitable strategy for wood modification/treatment. Given the requirements of biodeteriorating organisms for growth and wood degradation, it is expected that the new nanotechnology-based approaches to enhance wood durability may provide innovative broad-spectrum biocidal nanosystems. These systems can simultaneously induce alterations in the physicochemical properties of wood, thereby constraining the availability of the growth requirements. These alterations can efficiently inhibit the biodeterioration process by decreasing water absorption, restricting access to the wood components, and reducing void spaces within the wood structure. Finally, this review highlights the new opportunities, challenges, and perspectives of nanotechnology methods for biodeterioration-resistant wood, through which some techno-economic, environmental and safety aspects associated with these methods are addressed.
Recent development and challenges in enhancing fire performance on wood and wood-based composites: A 10-year review from 2012 to 2021
Charles Michael Albert, Kang Chiang Liew
2024, 9(1): 27-42.   doi: 10.1016/j.jobab.2023.10.004
[Abstract](28) [PDF 1233KB](2)
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Due to their durability, versatility, and aesthetic value, wood and wood-based composites are widely used as building materials. The fact that these materials are flammable, however, raises a major worry since they might cause fire hazards and significant loss of life and property. The article investigates the variables that affect fire performance as well as the various fire-retardant treatments and their mechanisms. The current developments and challenges in improving the fire performance of wood and wood-based composites treated with fire-retardant materials are summarized in this paper. Nanoparticles, organic chemicals, and densification are some recent developments in fire-retardant treatments that are also emphasized. Key points from the review are summarized, along with potential areas for further research and development.
Research Article
The Pichia pastoris enzyme production platform: From combinatorial library screening to bench-top fermentation on residual cyanobacterial biomass
Korbinian Sinzinger, Ulrike Obst, Samed Güner, Manuel Döring, Magdalena Haslbeck, Doris Schieder, Volker Sieber
2024, 9(1): 43-57.   doi: 10.1016/j.jobab.2023.12.005
[Abstract](36) [PDF 3137KB](1)
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The demand for industrial enzymes is continually rising, fueled by the growing need to shift towards more sustainable industrial processes. However, making efficient enzyme production strains and identifying optimal enzyme expression conditions remains a challenge. Moreover, the production of the enzymes themselves comes with unavoidable impacts, e.g., the need to utilize secondary feedstocks. Here, we take a more holistic view of bioprocess development and report an integrative approach that allows us to rapidly identify improved enzyme expression and secretion conditions and make use of cyanobacterial waste biomass as feed for supporting Pichia pastoris fermentation. We demonstrate these capabilities by producing a phytase secreted by P. pastoris that is grown on cyanobacterium hydrolysate and buffered glycerol-complex (BMGY) medium, with genetic expression conditions identified by high-throughput screening of a randomized secretion library. When our best-performing strain is grown in a fed-batch fermentation on BMGY, we reach over 7 000 U/mL in three days.
Adsorption of pharmaceutical pollutants on ZnCl2-activated biochar from corn cob: Efficiency, selectivity and mechanism
Christian F. Varela, L. C. Moreno-Aldana, Yazmin Yaneth Agámez-Pertuz
2024, 9(1): 58-73.   doi: 10.1016/j.jobab.2023.10.003
[Abstract](22) [PDF 2877KB](2)
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The occurrence of pharmaceuticals in water bodies and drinking water poses risks for the environment and human health, thus it is necessary to study methodologies that allow the efficient removal of these contaminants. In this work, corn cob-derived biochar was obtained by ZnCl2-activation, and subsequent carbonization at 700 °C. The effect of contact time, temperature, pH, and initial concentration on the adsorption capacity of acetaminophen (ACE) and amoxicillin (AMX) was determined through batch experiments. In addition, the kinetics, isotherms, and thermodynamics parameters were determined. The activated biochar exhibited a maximum adsorption capacity of 332.08 mg/g for ACE and 175.86 mg/g for AMX. The adsorption kinetics and adsorption isotherm of ACE corresponded to the pseudo-second order and Langmuir model, respectively. Meanwhile, pseudo-first-order kinetics and the Freundlich isotherm model were well-fitted to AMX adsorption. The ACE and AMX co-adsorption had a synergistic effect on AMX but an antagonistic effect on ACE removal, achieving a maximum adsorption capacity of 193.51 and 184.58 mg/g, respectively. On the other hand, fixed-bed column experiments showed that the adsorption capacity depends on the influent concentration, and the breakthrough curve fits the Thomas and Yoon-Nelson model. The mechanism adsorption studies showed that surface interactions (hydrogen bonding formation and n-π interactions) are the main driving forces for the adsorption process, and pore filling is the rate-limiting step. In this way, the prepared biochar exhibits a high potential for the adsorption of pharmaceutical compounds from water.
Development of sustainable thermal insulation based on bio-polyester filled with date pits
Amal Mlhem, Thomas Teklebrhan, Evenezer Bokuretsion, Basim Abu-Jdayil
2024, 9(1): 74-89.   doi: 10.1016/j.jobab.2023.12.004
[Abstract](25) [PDF 3983KB](2)
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Date palm pit (DPP)-filled poly (-hydroxybutyrate) (PHB) composites were prepared, evaluated, and characterized to determine their thermal insulation ability. Thermal conductivity values ranged between 0.086 and 0.100 W/(m·K). At a maximum filler concentration (50% (w)), the specific heat capacity and thermal diffusivity were 1 183 J/(kg·K) and 0.068 9 mm2/s, respectively. The DPP increased the thermal stability, and the highest compressive strength obtained was 80 MPa at 30% filler content. The PHB-DPP composites exhibited promising water absorption (less than 6%) and tensile strength (6-14 MPa). Date-pit-based PHB composites could be used in sustainable building engineering and cleaner production.
In situ biosynthesis of bacterial cellulose hydrogel spheroids with tunable dimensions
Bianjing Sun, Ping Wang, Jingang Zhang, Jianbin Lin, Lingling Sun, Xiaokun Wang, Chuntao Chen, Dongping Sun
2024, 9(1): 90-101.   doi: 10.1016/j.jobab.2023.12.003
[Abstract](64) [PDF 3800KB](6)
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Bacterial cellulose (BC) hydrogel spheroid plays a significant role in diverse fields due to its spatial 3D structure and properties. In the present work, a series of BC spheroids with controllable size and shape was obtained via an in situ biosynthesis. Crucial factors for fabricating BC spheroid including inoculum concentration of 1.35 × 103 CFU/mL, shaking speeds at 100 r/min, and 48-96 h incubation time during the biosynthetic process, were comprehensively established. An operable mechanism model for tuning the size of BC spheroids from 0.4 to 5.0 mm was proposed with a fresh feeding medium strategy of dynamic culture. The resulting BC spheroids exhibit an interactive 3D network of nanofibers, a crystallinity index of 72.3 %, a specific surface area of 91.2 m2/g, and good cytocompatibility. This study reinforces the understanding of BC spheroid formation and explores new horizons for the design of BC spheroids-derived functional matrix materials for medical care.
Structure and mechanical properties of windmill palm fiber with different delignification treatments
Changjie Chen, Pengfei Xu, Xinhou Wang
2024, 9(1): 102-112.   doi: 10.1016/j.jobab.2023.12.001
[Abstract](30) [PDF 2672KB](7)
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The removal of lignin from natural cellulose fibers is a crucial step in preparing high-performance materials, such as compressed high-toughness composites. This process can eliminate non-cellulosic impurities, create abundant compressible pores, and expose a greater number of active functional groups. In this study, biomass waste windmill palm fiber was used as the raw material to prepare holocellulose fibers through various chemical treatments. The structure, chemical composition, Fourier transform infrared spectroscopy analysis, X-ray diffraction analysis, thermal properties, and mechanical properties, particularly fatigue performance, were studied. The sodium chlorite treated fiber had the highest crystallinity index (61.3%) and the most complete appearance structure. The sodium sulfite treated fiber had the highest tensile strength (227.34 ± 52.27) MPa. Hydroxide peroxide treatment removed most of the lignin and hemicellulose, increasing the cellulose content to 68.83% ± 0.65%. However, all the chemical treatments decreased the thermal property of the fibers.
Improving antioxidant activities of water-soluble lignin-carbohydrate complex isolated from wheat stalk through prolonging ball-milling pretreatment and homogeneous extraction
Di Xie, Zhulan Liu, Yunfeng Cao, Sheng-I Yang, Chen Su, Mi Li
2024, 9(1): 113-125.   doi: 10.1016/j.jobab.2023.11.002
[Abstract](21) [PDF 2043KB](3)
Abstract:
Water-soluble lignin-carbohydrate complex (LCC) rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and lignin. However, the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still uncertain. Herein, structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations (4, 6, 8 h), extraction pathways (homogeneous and heterogeneous), and isolation routines (water extracts and residues after water extraction). Their structures were characterized by wet chemistry, chromatography and spectroscopies. Antioxidant activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate (RDPPH). Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble LCCs. Specifically, prolonging ball-milling duration to 8 hours and homogeneous extraction can enhance their antioxidant activity through releasing more phenolic structures and promoting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance, respectively. As a result, the RDPPH of water-soluble LCCs reaches up to 97.35%, which is associated with the arabinan content with statistical significance (P < 0.05). This study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.
Current Issue

Year 2024 Vol. 9 No.1

Table of Contents

CN32-1890/S7

ISSN 2369-9698

J. Bioresour. Bioprod.

Quarterly

Started in 2016

Editor-in-chief
Huining Xiao, Prof.

University of New Brunswick, Canada

 

Jianchun Jiang, Prof.

Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry, China