Background: The olive stone, a primary by-product of olive oil extraction, is mainly composed of a lignified shell and inner seed. It represents a substantial portion of the olive industry's biomass waste, contributing over 40 Mt annually. While typically regarded as waste, olive stones contain a variety of nutrients and bioactive compounds like lipids, proteins, phenolic compounds, and minerals found in the seed, as well as fibers in the shell. These elements hold significant value across multiple sectors, including food, energy, and agriculture. These phenolic compounds and nutrients provide notable antioxidant, anti-inflammatory, chemopreventive, and antimicrobial effects, supporting health and disease prevention. Scope and approach: This review explores the sustainable utilization of olive stone by-products, highlighting their potential to contribute to human health and environmental sustainability. It discusses the practical applications of olive stones in various domains, from functional ingredients in food products and pharmaceuticals to renewable energy sources and soil-enhancing agricultural inputs. Key findings and conclusions: Olive stones, particularly olive seeds, are rich in dietary fiber (47.6 %), lipids (30.4 %), proteins (13.5 %), and phenolic compounds (8.10 %), especially n & uuml;zhenide, n & uuml;zhenide 11-methyl oleoside and methoxyn & uuml;zhenide, and demonstrate a range of health-promoting properties. Additionally, they are shown to benefit metabolic health by combating disorders such as diabetes, hyperlipidemia, obesity, and car- diovascular and neurodegenerative diseases while also protecting organ functions like those of the liver and kidneys. The review underscores the promise of olive stone by-products as a sustainable, health-benefiting resource in circular economy practices within the olive oil industry.

A green process was devised to effectively extract cellulose from recycled rice straw waste, subsequently ethylating and modifying it into ethyl cellulose (EC), and ultimately blending the EC with ethanol to obtain biodegradable films. The optimal process conditions at each stage were investigated. An assessment was conducted on the crystallinity and thermal stability of rice straw cellulose (RSC), the degree of substitution of EC, and the biodegradability and mechanical properties of EC-ethanol films. The results demonstrated the following: The optimal process conditions resulted in a 95.73 % yield of extracted RSC, a type I crystalline structure, a 31.20 % increase in relative crystallinity, and thermal stability with a main weight loss peak at 340 C-degrees. Under ideal ethylation conditions, the EC production reached 79.60 %, while the degree of substitution ranged from 2.0 to 2.5. After being landfilled in soil for 100 days, the EC-ethanol films degraded at rates of 6.77 %, 4.78 %, and 3.13 % (film concentrations were 0.02, 0.04, and 0.06 g/mL (w/v, EC/ethanol), respectively). Based on the analysis of the films' FT-IR and SEM images, it was concluded that the EC-ethanol films exhibit favorable biodegradability. Moreover, the tensile strength of 0.04 g/mL film reaches up to 44.60 MPa. Hence, the EC-ethanol films in this research could be an environmentally friendly and sustainable alternative to plastic films.