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.

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.

New solutions are compulsorily needed to reconcile the enormous and ever-growing request for protein for human nutrition and, at the same time, reduce conventional meat production. This epochal challenge can find a valuable aid to a winning solution in insect rearing. The use of insects as feed and food, far from being a definitive solution to global food shortages, can offer new protein sources and perfectly fit circular economy precepts, yet more so when insects feed on by-products from the agri-food industry. In this scenario, Tenebrio molitor (TM) is a concrete alternative. Therefore, making its rearing more sustainable is a prime objective. In this paper, we evaluated the possibility of replacing usual plant sources of wet supplementation used in TM rearing with sustainable alternatives, including the cladodes of prickly pear (Opuntias ficus indica, OFI), to reduce the frequency of administration, thus minimizing related labor costs. The alternatives were tested for water content, dehydration, and shelf life to select the best-performing ones. On the selected matrices, we evaluated the preference of the larvae and their palatability because a matrix may be convenient and sustainable but not appreciated by consumers. The results showed that OFI cladodes have high moisture and a long shelf life and are appreciated by the larvae that prefer them to other matrices. Thus, OFI can replace the conventional wet source in TM rearing, at least in areas where this cactus grows wild and is not difficult to obtain.

The European Commission approval of some insect species for human consumption, starting with Tenebrio molitor (TM) in 2021, has drawn attention to the production of insect-derived protein flours and the sustainability of insect-rearing systems, particularly on a large scale. This has also highlighted the importance of utilizing byproducts, such as frass, and obtaining high-value-added products, such as biofertilizers. This study explored the potential for TM frass (TMF) to serve as a natural fertilizer for the cultivation of Canasta lettuce (Lactuca sativa var. capitata). Specifically, a series of tests was carried out to assess the efficacy of thermal treatment and to verify the trend of certain chemical and growth parameters as a function of the TMF percentage to be added to the potting soil. For this purpose, different percentages of both thermal-treated and untreated TMF and their effects on various growth parameters of Canasta lettuce were evaluated through pot trials. Furthermore, TMF was characterized by using scanning electron microscopy (SEM) to gain insights into its structural features and potential influence on soil–plant interactions. Our results show that heat treatment of TMF is essential to ensure plant survival, and at least in pots, TMF percentages above 5% of soil dry weight are not recommended. In our tests, the most suitable percentage was 4%.

The integration of sustainable insect rearing with green downstream processing is essential for the development of circular biorefineries. This study investigated the fractionation of Tenebrio molitor biomass obtained from larvae reared on diets containing agro-industrial by-products by bench-scale supercritical CO₂ (SC-CO₂) extraction. Larvae were reared on diets containing brewer’s spent grain (BSG), cocoa bean shell (CBS), or banana peel (BP). A preliminary process screening identified 40 °C and 200 bar as the most suitable extraction conditions, providing efficient fractionation under mild operating conditions. Lipid extraction yield depended on the initial composition of the insect meals, ranging from 6.47 ± 0.26% for BSG-derived biomass to 23.02 ± 1.52% for CBS-derived biomass. SC-CO₂ extraction simultaneously produced protein-enriched meals, increasing protein content up to 69.4 ± 0.7%, with protein enrichment ranging from 14.9% to 33.4%. The recovered oils exhibited a favorable fatty acid profile, with more than 72% unsaturated fatty acids, predominantly oleic and linoleic acids. These findings show that differences in the composition of insect biomass obtained under different rearing conditions are reflected in the yield and characteristics of the fractions recovered under identical extraction conditions. Integrating rearing substrate selection with SC-CO₂ extraction represents an effective strategy to produce high-value protein-enriched meals and oils from agro-industrial by-products, supporting the development of sustainable insect biorefineries.