The sustainable management of lignocellulosic agricultural waste has gained significant attention due to its potential for the production of valuable products. This paper provides an extensive overview of the valorization strategies employed to convert lignocellulosic agricultural waste into economically and environmentally valuable products. The manuscript examines the conversion routes employed for the production of valuable products from lignocellulosic agricultural waste. These include the production of biofuels, such as bioethanol and biodiesel, via biochemical and thermochemical processes. Additionally, the synthesis of platform chemicals, such as furfural, levulinic acid, and xylose, is explored, which serve as building blocks for the manufacturing of polymers, resins, and other high-value chemicals. Moreover, this overview highlights the potential of lignocellulosic agricultural waste in generating bio-based materials, including bio-based composites, bio-based plastics, and bio-based adsorbents. The utilization of lignocellulosic waste as feedstock for the production of enzymes, organic acids, and bioactive compounds is also discussed. The challenges and opportunities associated with lignocellulosic agricultural waste valorization are addressed, encompassing technological, economic, and environmental aspects. Overall, this paper provides a comprehensive overview of the valorization potential of lignocellulosic agricultural waste, highlighting its significance in transitioning towards a sustainable and circular bioeconomy. The insights presented here aim to inspire further research and development in the field of lignocellulosic waste valorization, fostering innovative approaches and promoting the utilization of this abundant resource for the production of valuable products.

Nowadays, it is urgent to produce in larger quantities and more sustainably to reduce the gap between food supply and demand. In a circular bioeconomy vision, insects receive great attention as a sustainable alternative to satisfy food and nutritional needs. Among all insects, Tenebrio molitor (TM) is the first insect approved by the European Food Safety Authority as a novel food in specific conditions and uses, testifying its growing relevance and potential. This review holistically presents the possible role of TM in the sustainable and circular solution to the growing needs for food and nutrients. We analyze all high value‐added products obtained from TM (powders and extracts, oils and fatty acids, proteins and peptides, and chitin and chitosan), their recovery processes (evaluating the best ones in technical and environmental terms), their nutritional and economical values, and their biological effects. Safety aspects are also mentioned. TM potential is undoubted, but some aspects still need to be discussed, including the health effects of substances and microorganisms in its body, the optimal production conditions (that affect product quality and safety), and TM capacity to convert by‐products into new products. Environmental, economic, social, and market feasibility studies are also required to analyze the new value chains. Finally, to unlock the enormous potential of edible insects as a source of nutritious and sustainable food, it will be necessary to overcome the cultural, psychological, and regulatory barriers still present in Western countries.

Chitin is the second most plentiful natural biomass after cellulose, with a yearly production of about 1 × 10¹⁰–1 × 10¹² tonnes. It can be obtained mainly from sea crustaceans' shells, containing 15–40% chitin. Full or partial deacetylation of chitin generates chitosan. Chitin and chitosan are used in several industrial sectors, as they exhibit high biocompatibility, biodegradability and several biological functions (e.g., antioxidant, antimicrobial and antitumoral activities). These biopolymers' market trends are destined to grow in the coming years, confirming their relevance. As a result, low-cost and industrial-scale production is the main challenge. Scientific literature reports two major technologies for chitin and chitosan recovery from crustacean waste: chemical and biological methods. The chemical treatment can be performed using conventional solvents, typically strong acid and alkaline solutions, or alternative green solvents, such as deep eutectic solvents (DESs) and natural deep eutectic solvents (NADESs). Biological methods use enzymatic or fermentation processes. For each route, this paper reviews the advantages and drawbacks in terms of environmental and economic sustainability. The conventional chemical method is still the most used but results in high environmental impacts. Green chemical methods by DESs and NADESs use low-toxic and biodegradable solvents but require high temperatures and long reaction times. Biological methods are eco-friendly but have limitations in the upscaling process, and are affected by high costs and long reaction times. This review focuses on the methodologies available to isolate chitin from crustaceans, providing a comprehensive overview. At the same time, it examines the chemical, biological and functional properties of chitin and its derivative, along with their most common applications. Consequently, this work represents a valuable knowledge tool for selecting and developing the most suitable and effective technologies to produce chitin and its derivatives.

Flaxseed lignans frequently feature in the literature. However, much remains to be discovered about the mechanisms underlying their functional and therapeutic properties. Furthermore, it is necessary to identify systems for lignan production and detoxification that are sustainable, cost-effective, easy to use, and scale up. These systems can address the needs of the nutraceutical, cosmetic, and pharmaceutical sectors and lead to competitive commercial products. This review analyzes the biological effects of lignans as anticancer, antioxidants, and modulators of estrogen activity. It also focuses on the most recent articles on lignan extraction methods that are sustainable and suitable as products for human consumption. Furthermore, the most up-to-date and relevant patents for lignan recovery are examined. The search and selection methodology for articles and patents was conducted using the most popular bibliographic and patent databases (e.g., Scopus, Pubmed, Espacenet). To the best of our knowledge, this is the first overview that details the patented technologies developed in the flaxseed lignans area in the last 10 years.

The projected growth of the global population to over 10 billion by 2080 necessitates groundbreaking sustainable agricultural solutions that enhance productivity while mitigating environmental impacts. Tenebrio molitor frass (TMF), derived from larval excrement and exuviae, has emerged as a promising organic fertilizer. Enriched with macro- and micronutrients, TMF enhances soil functions through microbial communities that promote nutrient cycling, decompose organic matter, and suppress soilborne pathogens. Additionally, functional compounds like chitin, cellulose, xylans, and lignin improve the soil structure, foster beneficial microbes, and activate natural plant defence responses. The synergy of microbial activity and bioactive compounds positions TMF as a valuable resource for enhancing plant growth and soil health. Its role as a nutrient source, biostimulant, and soil amendment aligns with circular economy principles by recycling agro-industrial by-products and reducing reliance on synthetic fertilizers. TMF also contributes to sustainable agriculture by improving soil fertility, microbial biodiversity, and plant stress resilience, while mitigating greenhouse gas emissions and nutrient runoff. Additionally, TMF-derived biochar offers the potential for environmental remediation as an effective adsorbent. Despite its advantages, TMF faces challenges in scalability, cost, and regulations, requiring advancements in processing, enrichment, and supportive policies to maximize its potential in sustainable farming.

Globally, the growing production of food commodities generates significant quantities of agroindustrial residues, most of which are untreated and disposed of as waste through either burning, dumping into the land, or unplanned landfilling, thereby causing environmental pollution, public health problems, and decreased soil organic matter and soil productivity. A literature review has been conducted on the current crop residue biomass valorization, analyzing raw material properties and the potential risks associated with its incorrect or absent management, as well as the major microbial fermentation strategies that are used for converting residual crops into valuable products. Approximately 2445.2 million tons of crop residues are produced worldwide. Microbial fermentation is an efficient way of managing residues that are rich in nutrients (e.g., nitrogen, phosphorus, and potassium) and converting them into single-cell proteins, antibiotics, enzymes, bioalcohols, polysaccharides, fine chemicals, and others, thereby supporting a circular bioeconomy. Although separate saccharification and fermentation (SHF) represent the predominant fermentation strategy, it requires considerable equipment costs and a long process time, which can lead to the formation of contaminations and inhibitors. Alternative conversion strategies, including simultaneous saccharification and fermentation (SSF), simultaneous saccharification and co-fermentation (SSCF), and consolidated bioprocessing (CBP), can reduce time and production costs, contaminations, and inhibitor formation, and enhance process yields. Nevertheless, combining hydrolysis and fermentation into a single phase results in non-optimal temperature and pH. This review discusses crop residue valorization through fermentation strategies, and provides a 360-degree view of the topic. After investigating the major types of crop residues and the potential environmental risks associated with their incorrect or absent management, it analyzes the key steps in the crop residue bioconversion process, and the most common microorganisms and microbial cultures. In addition, this review reports on various examples of crop residues being converted into industrial products and analyzes the main fermentation strategies (SHF, SSF, SSCF, and CBP), highlighting their strengths and weaknesses. As a matter of fact, fermentation strategies need to be compared for their benefits and disadvantages before being implemented on a large scale. In addition, the properties and availability of the raw materials, investment, and operating costs, the skilled workforce availability, sustainability, and the return on investment all need to be evaluated. Finally, the discussion focus on future outlooks and challenges.