2024, Vol. 9, No. 1

Display Method:
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
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
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
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
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
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
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
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
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
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.