Bioresource Technology Reports最新文献

This study presents a comparative analysis of different kinetic models applied to the thermochemical pyrolysis of palm empty fruit bunch (PEFB). The kinetic parameters, particularly the activation energy, are determined through thermogravimetric analysis (TGA) of samples that underwent heating rates ranging from 10 to 50 °C/min. Image analysis of PEFB in a hot-stage microscope reveals an intriguing correlation between the observed shrinkage and the conversion rate (α) and indicates that significant physical and chemical transformations occurred within α between 0.2 and 0.8. The experimental data from TGA demonstrates good alignment with four distinct kinetic models. The Coast-Redfern model gives activation energies ranging from 60 to 134 kJ/mol for α between 0.2 and 0.8. In contrast, the Kissinger model and the isoconversion models, Kissinger-Akahira-Sunose and Ozawa-Flyn-Wall, show higher activation energy of 151, 156, and 157 kJ/mol, respectively. The findings underscore the significant impact of the selected kinetic model on determining kinetic parameters.

This work discusses the valorisation and efficacy of the acid-extracted collagenous proteins from leather buffing dust (LBD) on the corrosion inhibition of mild steel (MS) in 0.5 M H₂SO₄ solution using electrochemical analysis. The extract shows ~95 % inhibition efficiency at 1 wt% of raw LBD loading. The inhibitor interaction follows Langmuir adsorption isotherm, indicating monolayer adsorption through physisorption, leading to complex formation on the MS surface. Post-corrosion characterizations reveal film-forming nature of the inhibitor and the involvement of organic compounds in the complex protective layer formation on the MS in the corrosive media. In addition, surface study through an optical profilometer helps to understand the nature of the corroded MS. In summary, the LBD-H₂SO₄ extract is extremely capable in mitigating the corrosion of MS in H₂SO₄ solution, and the inhibition phenomenon is governed by a complex passive layer formation on the MS subjected to the corrosive media.

Green hydrogen is one of the alternative options to decarbonize the energy sector and limit the global temperature rise below 1.5 °C. Vietnam has various biomass resources, including agricultural and forestry by-products. However, this country has not had any research to evaluate the suitability of hydrogen production technologies using biomass sources in general and agricultural residues in particular with all relevant factors as a basis for investment and development. The paper assesses three green hydrogen production technologies from agricultural residue, including pyrolysis, gasification, and fermentation, by simultaneously applying the Strength Weakness Opportunity Threat (SWOT) analysis and Analytic Hierarchy Process (AHP). The hydrogen production technologies and agricultural residues in Vietnam are used as case studies. The obtained results on the weighting factors indicate that the economic indicator accounts for 50.7 %, followed by the technical indicator at 27.8 % and the environmental indicator at 21.5 %. Among the hydrogen production technologies, gasification is the most prioritized technology, at 43.3 %. The priorities of pyrolysis and fermentation are not considerably different, at 29.6 % and 27.1 %, respectively. Rice straw has the highest hydrogen production capacity with a total potential of about 50.43 billion m³ while the lowest total hydrogen production potential is cassava pomace with a value of 0.26 billion m³. Designing and simulating the hydrogen production process from agricultural waste using selected technologies will be studied in further work to finalize and verify the used assumptions, methods, and information in this study.

An anaerobic hybrid-photobioreactor (AnHPBR) was performed for biogas polishing during piggery wastewater treatment. AnHPBR was exposed to high (4.45 × 10⁵ lx) and low (450 lx) light intensities for growing purple and green sulfur phototrophs separately in each chamber of AnHBBR for soluble sulfide removals. Four phases of hydraulic retention times (HRT, h): 24, 48, 96, and 96 (with added sulfate) of piggery wastewater were operated consecutively for 351 days. Metagenomic analysis of the AnHPBR biomass confirmed that purple and green bacteria were 63–82 %, of which the species varied by HRT and sulfate loadings. In sum, 96 h HRT for AnHPBR presented the highest efficacies in removals of COD (92 %), sulfate (73 %), and sulfide (59 %). Its biogas contained high methane (75 %) and low hydrogen sulfide (0.3 %). Additionally, AnHPBR produced outflow biosolids with a stable sulfur content of 1.88 %.

Laccases are crucial for agro-waste delignification in sustainable practices. Considering the necessity for cost-effective laccase pretreatments in industrial applications, numerous efforts have been directed towards identifying potential enzyme inducers for increasing laccase production. This study explored corn steep liquor as a cost-effective laccase inducer in Pleurotus pulmonarius solid substrate fermentation of tender coconut fiber. Utilizing tender coconut fiber for laccase production offers dual benefits of fiber valorisation and enzyme synthesis sustainably. We investigated the impact of corn steep liquor on transcription of Lac1 gene in P. pulmonarius and on extracellular laccase activity. Adding 2 % CSL notably boosted laccase production (314.62 + 5.93 IU/mL) and increased Lac1 transcript levels by 5.6-fold compared to non-induced cultures. SEM analysis revealed improved delignification as a result of increased laccase production. Our findings suggest that corn steep liquor serves as an inducer for regulating laccase gene expression in P. pulmonarius, leading to increased extracellular laccase production.

The production of lignocellulolytic enzymes from agricultural waste offers a sustainable and cost-effective approach. These enzymes, including cellulases, hemicellulases, and ligninases, decompose plant biomass into basic components. This review explores agricultural waste as a substrate, highlighting its abundance and potential for converting waste into resources. Various microorganisms, like fungi and bacteria, are evaluated for enzyme production adaptability. Different production processes, such as solid-state fermentation and submerged fermentation, are compared for efficiency and scalability. Pretreatment dismantles the raw material's structure, enhancing product yield despite increased energy consumption. Optimization strategies, including culture conditions and genetic engineering, improve enzyme production. Challenges in enzyme production from agricultural waste are addressed, with proposed solutions. The review also discusses diverse applications of lignocellulolytic enzymes, from biofuels to textiles, emphasizing environmental and economic benefits. It emphasizes agricultural waste's promise as a substrate for enzyme production, offering opportunities for sustainability and economic viability, and highlights future research directions.

Motivated by the urgent need to address dye-related environmental pollution, this study explores the green synthesis of silver nanoparticles (AgNPs) using Thunbergia grandiflora leaf extract for its simplicity, affordability, and eco-friendliness. UV–Vis spectroscopy reveals a distinctive signal at 441 nm, while Dynamic Light Scattering shows a zeta potential charge of −18.2 mV, indicating nanoparticle stability. The study demonstrates the catalytic activity of AgNPs in degrading industrial dyes Acid Red 88 and Methylene Blue, showcasing first-order kinetics with kinetic constants of 0.18 min⁻¹ and 0.14 min⁻¹, respectively. Moreover, Scanning Electron Microscopic images reveal predominantly spherical nanostructures, while X-ray diffractometry analysis portrays a face-centered crystalline structure. These findings underscore the potential of AgNPs synthesized from T. grandiflora leaf extract in nanoremediation efforts, offering a sustainable solution to the pressing challenge of dye-contaminated wastewater, thereby contributing to environmental protection.

A low energy-consuming system for greywater treatment was developed with a trickling filter (TF) followed by constructed wetlands (CWs). Roles of substrates, plants, and microorganisms were intentionally explored. TFs and CWs were filled with recycled foamed glass. Water spinach and parsley planted in the CWs provided additional value. Microorganisms in the system were characterized through carbon-utilization tests and 16S rRNA gene next-generation sequencing. In 5.5 months, TOC, TN, and TP removals from greywater were, respectively, 83.5, 85.5, and 92.1 %. TOC was removed in the TF at 22.6 g-C/m²/d. The CWs exhibited TN and TP removals at 0.44 g-N /m²/d and 0.19 g-P/m²/d. Water spinach was harvested at 792 g-wet/m²/week, accounting for 7.1 % and 12.6 % for TN and TP removals. Denitrification, microbial diversity, and carbon source utilization potentials were enhanced by water spinach. This is a sustainable wastewater treatment model by using recycled materials and edible plants.

Chromochloris zofingiensis was cultured with different carbon sources (carbonate/glucose/acetate/pyruvate) and light conditions (dark/blue/red) under heterotrophic, autotrophic, and mixotrophic conditions to evaluate its energy utilization efficiency in terms of biomass and carotenoid accumulation. Enhanced specific growth rates of 0.58 d⁻¹ and 0.51 d⁻¹ were observed under blue- and red-light mixotrophic conditions, respectively, which both exceeded the rate of 0.44 d⁻¹ obtained under heterotrophic conditions using a glucose-supplemented medium. The glucose medium showed superior cell synthesis compared to other carbon sources owing to its high utilization. Astaxanthin and neoxanthin accumulation were enhanced under mixotrophic conditions with blue-light. The energy efficiency for the synthesis of new cells was evaluated from a thermodynamic perspective. The efficiency was 1.1 to 2.1 % under autotrophic conditions, while 5.2 to 100 % was observed under heterotrophic conditions. Efficiencies in between were observed under mixotrophic conditions.

Deproteinization of shrimp waste (Litopenaeus vannamei) was achieved by biotechnological treatment using bacterial consortia. Five bacterial consortia (CB01, CB02, CB03, CB04 and CB05) were separately evaluated under a factorial design 2³, including the effect of temperature (25 and 35 °C), time (16 and 24 h) and volume of inoculum (2 and 6 mL × 10⁷ CFU/mL).

Bacterial consortium CB05 showed the highest deproteinization (DP) effect. The best response was achieved at 35 °C, 6 × 10⁷ CFU/mL, and 16 h of bioprocess. Protein content was reduced by 99.5 %.