Resource Recovery and Microbial Transformation of Organic Solid Waste

Dear Colleagues,

The dramatic increase in global organic solid waste (e.g., sewage sludge, food waste, agricultural residues) poses severe challenges to sustainable development and the green transition of agriculture. Microbial-driven biotransformation technologies, such as composting and fermentation, are pivotal for waste valorization, advancing the circular economy, and contributing to the "Dual Carbon" goals. This Special Issue focuses on microbial community succession, metabolic networks, and regulatory mechanisms of composting. The research aims to optimize process efficiency and enhance the value of end-products, thereby providing theoretical and technical support for building high-performance integrated "Waste-Agriculture-Environment" systems.

We sincerely welcome submissions spanning cross-disciplinary fields such as Environmental Science, Environmental Engineering, Agricultural Engineering, Microbiology, Agricultural Resource Utilization, Bioengineering, and Synthetic Biology. This Special Issue focuses on leveraging cutting-edge microbial technologies to address key bottlenecks in waste processing—including efficiency, product stability, and environmental risks—and to provide a scientific basis and practical case studies for large-scale engineering applications.

The themes encompassed by this section include, but are not limited to, the following:

1. Mining of Functional Microorganisms and Their Metabolic Interactions

• Isolation, screening, and functional identification of high-efficiency functional microorganisms (e.g., lignocellulose-degrading bacteria, thermophiles, psychrophiles, emission-reducing bacteria, heavy metal-immobilizing bacteria).
• Activity regulation and adaptive evolution mechanisms of key microbial enzyme systems (e.g., cellulase, hemicellulase, ligninase, protease).
• Metabolic interactions and synergistic degradation networks of microorganisms within complex waste systems (e.g., sewage sludge, solid waste, food waste, straw).

2. Optimization of Fermentation Processes and Directed Regulation of Products

• The relationship between microbial community dynamics and environmental factors (e.g., temperature, pH, C/N ratio, oxygen) during aerobic composting and anaerobic fermentation.
• Directed enhancement of microbial synthesis pathways for target products (e.g., humic acids, biogas, volatile fatty acids, protein feed).
• The transport, transformation, and biodegradation mechanisms of emerging contaminants (e.g., heavy metals, antibiotics, microplastics) during biological treatment processes.

3. Synthetic Microbial Consortia and Process Enhancement Technologies

• Rational design and functional validation of efficient Synthetic Microbial Consortia (SynComs) tailored for specific waste components.
• The regulatory effects of exogenous additives (e.g., biochar, montmorillonite, enzyme preparations) on microbial activity and the fermentation process.
• Application of intelligent sensing, the Internet of Things (IoT), and big data analytics for the intelligent monitoring of large-scale fermentation systems.

4. Agricultural and Environmental Effects of Waste-Derived Products and Risk Control

• Evaluation of the effects of matured compost, bio-organic fertilizers, and similar products on soil physicochemical properties, microbial community structure, and crop growth.
• Application potential of waste-based products in rehabilitating degraded soils (e.g., saline-alkali soil, compacted soil) and the associated microbial ecological feedback mechanisms.
• Risk assessment of environmental safety from agricultural waste application (e.g., heavy metal accumulation, antibiotic resistance gene dissemination) and research into safe threshold levels.

Dr. Jinling Cai
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Fermentation is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2100 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• organic solid waste
• microorganisms
• compost
• fermentation
• community succession
• resource recovery