Search Results (319)

This study evaluated the extraction efficiency of two Natural Deep Eutectic Solvents (NADESs), glycerol–urea (1:1) and citric acid–sorbitol (1:2), for recovering phenolic compounds from the different parts of the fruit (pulp, seed-containing pulp, seeds, and peel) of Opuntia robusta and Opuntia ficus-indica in comparison with 50% methanol. Phytochemical profiling was performed using ultra-high-performance liquid chromatography–high-resolution mass spectrometry, alongside antioxidant and enzyme inhibition assessments (acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-glucosidase, and α-amylase). Glycerol–urea performed similarly to methanol in extracting phenolic compounds with notable antioxidant properties. Peel extracts contained the highest levels of bioactive compounds, particularly phenolic acids (525.49 in O. robusta and 362.96 µg/g_DW in O. ficus indica). Enzyme inhibition varied across species and fruit parts, with extracts from both species inhibiting all targeted enzymes. Notably, this study provides the first evidence of tyrosinase inhibitory activity in O. robusta, which exhibited the strongest inhibition. Overall, these results emphasize the potential of cactus fruit extracts, particularly from O. robusta, for valorization, and support the use of NADESs as a sustainable and medium for extracting antioxidant compounds. Furthermore, the potential of fruit peel as waste with nutraceutical applications was demonstrated. Full article

Opuntia ficus-indica peel waste (OPW) accounts for approximately 50% of the fresh fruit weight, a relatively higher rate in comparison to other fruits, making it a particularly abundant and underutilized agricultural by-product. This study investigates Tunisian OPW through convective drying (50, 60, 75, and 85 °C) using four different pretreatments: no pretreatment (Fresh OPW), dipped peels in acetic acid solution (AA OPW), frozen and thawed peels (FZ OPW), and dipped–frozen combined pretreatment (AA-FZ OPW). The drying kinetic evaluation clearly demonstrated an increase in drying rate by lowering the required drying time for the various pretreatments and drying temperatures. This drying time decreased by 8.64–17.39%, 23.46–36.70%, and 28.39–39.45% for AA OPW, FZ OPW, and AA-FZ OPW, respectively, as compared to fresh OPW. The total phenolic and betalain contents, found in dried OPW, ranged from 7.87 ± 0.254 g GAE/100 g dw to 12.29 ± 0.421 g GAE/100 g dw and from 22.74 ± 2.34 mg/100 g dw to 59.86 ± 3.24 mg/100 g dw, depending on the drying temperature and pretreatment applied. This study employs thin-layer and artificial neural network (ANN) modelling, finding that both methods produce highly accurate moisture-ratio prediction during the drying process. The peels from Opuntia ficus-indica have considerable potential to be reused as functional ingredients. Full article

The escalating release of synthetic dyes from textile and allied industries has become a pressing global environmental issue due to their toxicity, persistence, and resistance to biodegradation. Among the various treatment strategies, adsorption has emerged as one of the most efficient, economical, and sustainable techniques for dye removal from aqueous environments. This review highlights recent advances in bio-derived adsorbents—particularly raw biomass powders, biochars, and activated carbons—developed from renewable waste sources such as agricultural residues, fruit peels, shells, and plant fibers. It systematically discusses adsorption mechanisms, the influence of process parameters, kinetic and thermodynamic models, and regeneration performance. Furthermore, the review emphasizes the superior adsorption efficiency and cost-effectiveness of biomass-derived carbons compared to conventional adsorbents. The integration of surface modification, magnetization, and nanocomposite formation has further enhanced dye uptake and reusability. Overall, this study underscores the potential of biomass-derived materials as sustainable alternatives for wastewater treatment and environmental remediation. Full article

Biogas and methane generated from the anaerobic digestion (AD) of organic waste present a highly effective alternative to fossil fuels. The study assessed using dragon fruit peel (DFP) as a co-substrate to enhance chicken manure (CM) biodegradability and stabilize the AD process for methane during co-digestion. The biochemical methane potential assays were conducted at mono-controls (CM and DFP) and co-digestion at CM-75:DFP-25, CM-50:DFP-50, and CM-25:DFP-75. Compared to the controls, mono-digestion produced 103.3 mL/g of volatile solids (VSs) of CM and 34.6 mL/g VS of DFP, while all treatment groups of co-digestion exhibited an increase in methane production. The highest yield was 180.3 mL/g VS at CM-25:DFP-75 (74.6% and 421.1% increase relative to mono-digestions of CM and DFP, respectively), followed by 148.3 mL/g VS at CM-50:DFP-50 (43.6% higher than CM) and 116.7 mL/g VS at CM-75:DFP-25 (13% higher than CM). Process stability at the optimal DFP co-substrate ratio (CM-25:DFP-75) was confirmed by total volatile fatty acid (VFA) conversion, as below 0.5 g/L VFAs were observed at the end of incubation, indicating highly acceptable performance. The relative abundance of Bacteroidetes and Bacillota in the treatment groups was higher as compared to the control reactors, correlating with enhanced substrate hydrolysis and VFA production. Moreover, the enrichment of acetoclastic methanogens Methanosarcina and Methanosaeta in co-digesters at CM-25:DFP-75 was associated with the efficient degradation of acetic acid and propionic acid, which aligns with the observed increase in methane yield. The study enhances the understanding of DFP as a co-substrate for optimizing methane recovery from AD of CM. Full article

Packaging plays a crucial role in extending the shelf life of fresh fruits and vegetables, thereby preserving their quality characteristics throughout the supply chain. Packaging systems treated with natural compounds can replace synthetic packaging systems. This study aimed to evaluate the potential application of active cardboard packaging (ACP) in preserving fruit quality and extending its shelf life. We observed the effect of cardboard packaging containing Punica granatum peel extract (PPGE) and Rumex crispus root extract (RRCE) on the shelf life of strawberries, tomatoes, and table grapes. In vitro and in vivo tests demonstrated the ability of RRCE + PPGE (group A) and PPGE (group B), once incorporated into the packaging at a concentration of 8%, to create a system capable of inhibiting microbial growth, thus prolonging the freshness and marketability of the fruit. Conventional packaging (group C) was taken as control. Strawberry groups A and B showed disease severity (DS) values of 55.9 and 51.8%, significantly lower than the 87.7% found in group C. Similar findings were observed in table grapes and datterini tomatoes. Quality was also assessed by measuring the surface color of homogenized strawberries, grapes and tomatoes, using a spectrophotometer. In strawberries, after 4 days, the colorimetric values in groups A and B were 26.86 and 34.50, respectively, much higher than the 13.99 recorded in untreated strawberries (group C). In table grapes and datterini tomatoes, the same results as those obtained in strawberries were confirmed. This study offers a novel approach to extending the shelf life of fruits and vegetables. We believe this technology, in addition to being an excellent bioactive packaging solution capable of reducing losses and improving quality in the fruit supply chain, is also economically viable since PPGE is derived from pomegranate processing waste and RRCE is obtained from the roots of a weed. Full article

Plum peel is a major by-product of plum processing and a rich source of nutrients and bioactive compounds. This study aimed to optimize a black plum peel spread formulated with apple puree (20–40%) and plum puree (10–30%) using response surface methodology (RSM). Increasing apple puree up to 30% reduced acidity, firmness, cohesiveness, and consistency while improving sourness and overall acceptability. At 40%, apple puree decreased total acceptability and sourness while slightly increasing texture parameters. Increasing plum puree up to 20% lowered acidity, firmness, consistency, cohesiveness, viscosity, and sourness, but further increases to 30% reversed these effects. Both apple and plum purees enhanced antioxidant capacity in a concentration-dependent manner. The interaction between apple and plum purees notably affected the viscosity of the spread. Overall, plum puree had the strongest influence on texture and color, while apple puree primarily affected sensory acceptance. The optimal formulation was 32.01% apple puree and 28.16% plum puree (R² = 0.999). Developing a spread from black plum peel demonstrates a sustainable strategy for upcycling fruit-processing waste into nutritious, high-value products. This approach reduces environmental impact, supports circular food production, and creates new opportunities for functional spreads in the health-oriented food markets. Full article

It is well known that food waste, especially perishable fruits, is one of the pressing issues worldwide, and as much as 50% of harvested fruits are wasted in developing countries as a result of poor preservation methods. Other traditional options such as plastic films or chemical preservatives are harmful to the environment and to our health. In this work, the limitations are overcome through the fabrication of an innovative camellia saponin/sodium alginate (CS/SA) composite hydrogel film that not only recycles agricultural waste but also improves fruit protection. CS/SA films were prepared by ionic crosslinking with CaCl₂ with different CS content (0–10% w/v, corresponding to 0–3.1 wt% in air-dried films). Detailed SEM, FTIR, XRD and rheological studies indicated that CS addition led to a gradual microstructural densification, stronger intermolecular interactions (involving hydrogen bonding and electrostatic complexation) and superior viscoelasticity, with the best performance at 8% CS (2.5 wt% in dried film). Mechanical tests confirmed that the stable CS/SA film showed higher tensile strength (152 kPa) and compressive strength (353 kPa) than pure SA (10 kPa) with a relatively low Young’s modulus (0.82 MPa) and high elongation at break (116.33%), which could be easily peeled off from fruit surfaces—an essential benefit of this over stiff chitosan/alginate composites. Structure: The composite film exhibited lower porosity (103.2%), reduced moisture content (94.7%), a controlled swelling ratio (800%) and improved barrier property with a water vapor permeability of 1.3 $\times {10}^{-6}$ g·m⁻¹·s⁻¹·kPa⁻¹ and an oxygen permeability of 1.9 × cm³$·\mathsf{\mu }$m·m⁻²·d⁻¹·kPa⁻¹. The 8% CS film showed very strong antioxidant activity (86% DPPH scavenging). Results of application tests on bananas and strawberries indicated that the ripening process was delayed by the CS/SA coatings, the decay rate was decreased from 99.9% (uncoated control) to 55.6% after 9 days, the weight loss was reduced to 29.3%, and the fruit’s firmness and titratable acidity were maintained. This degradable, multifunctional hydrogel film has the potential to be a sustainable measure to simultaneously mitigate food waste, valorize agricultural byproducts, and protect the environment, which could offer substantial benefit for enhancing global food security as well as fruit shelf life. Full article

Lead (Pb) pollution in wastewater is an immense problem for public health and the environment because it persists in the water bodies for a long period of time. Over the past years, many different techniques of Pb remediation have been discovered to eliminate Pb pollution. This systematic review analyzed the major findings of Pb removal from wastewater using microbial biosorption, agro-waste- and fruit peel-based adsorbents, plant-assisted phytoremediation, engineered biochars, clay and natural minerals, and nanomaterials. Each of these methods is critically reviewed in terms of removal efficiency, limitations, cost-effectiveness, how it works, how well it eliminates the problem, environmental compatibility, regeneration potential, and scalability, as supported by recent experimental and case studies. This review provides a comprehensive comparison of all the remediation methods in one framework. It also shows the potential of the integrated and hybrid systems, a combination of biological and high-technology material-based strategies, to reach high-performance Pb remediation in the long run. Therefore, the study aims to assist policymakers, environmental engineers, and researchers who are interested in finding a sustainable solution to Pb contamination by providing a comparative overview of the existing and recently developed remediation methods. Full article

Citrus fruits are among the most important global crops, with annual production exceeding 160 million tons. Processing produces significant waste, mainly peels, seeds, and pulp, which can make up to fifty percent of the fruit’s mass. This review critically examines innovative ways to valorize these byproducts. Recent research shows that peels, seeds, and pulp can be converted into high-value materials, including biocomposites and biomaterials, marking a shift from traditional uses like animal feed and biogas production. Notable innovations include smart packaging, pectin-based wound dressings, and biodegradable polymers for sustainable electronics. Advanced green extraction methods, such as deep eutectic solvents, have achieved extraction yields over 85% for flavonoids. Additionally, multifunctional biorefineries processing citrus and olive residues have increased biogas yields by 38–42%. The review explores emerging applications in nanotechnology, nutraceuticals, biodegradable polymers, and functional coatings, all aligned with principles of circular economy and green chemistry. These advances suggest that citrus waste can play a significant role in sustainability efforts and new market development. The review also discusses barriers to adoption, including scalability challenges, regulatory limits, and consumer acceptance, from both global and regional viewpoints. Full article

Agri-food residues have accumulated globally at unprecedented scales, generating environmental pressures and resource inefficiencies, a core problem addressed in this review, while simultaneously representing rich, underutilized reservoirs of health-promoting phytochemicals. This review synthesizes recent advances (2016–2025) in the green extraction, characterization, and biological validation of phytochemicals from plant-based residues, including polyphenols, flavonoids, carotenoids, alkaloids, and dietary fibers from key sources such as grape pomace, citrus peels, coffee silverskin, pomegranate peel, cereal brans, and tropical fruit by-products. Emphasis is placed on sustainable extraction methods: ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), supercritical CO₂ extraction (SFE), and natural deep eutectic solvents (NADES), which enable efficient recovery while minimizing environmental impact. In vitro, in vivo, and clinical studies demonstrate that residue-derived compounds exert antioxidant, anti-inflammatory, metabolic-regulating, and prebiotic effects, contributing to health in general and gut microbiota modulation. Integrating these bioactives into functional foods and nutraceuticals supports sustainable nutrition and circular bioeconomy goals by reducing food waste and promoting health-oriented valorization. Regulatory advances, including approvals from the European Food Safety Authority (EFSA) and the U.S. Food and Drug Administration (FDA) for ingredients such as olive phenolics, citrus flavanones, and coffee cascara, further illustrate increasing translational readiness. The convergence of green chemistry, biorefinery design, and nutritional science positions agri-food residues as pivotal resources for future health-promoting and environmentally responsible diets. Remaining challenges include scaling cost-effective green processes, harmonizing life cycle assessment protocols, expanding toxicological datasets, and conducting longer-term clinical trials to support safe and evidence-based commercialization. Full article

Agricultural and agro-industrial waste, produced in vast quantities worldwide, presents both environmental and economic challenges. Microbial valorization offers a sustainable solution, with bacterial cellulose (BC) emerging as a high-value product due to its purity, strength, biocompatibility, and biodegradability. This review highlights recent advances in producing BC from agricultural and agro-industrial residues via optimized fermentation processes, including static and agitated cultivation, co-cultivation, stepwise nutrient feeding, and genetic engineering. Diverse wastes such as fruit peels, sugarcane bagasse, cereal straws, and corn stover serve as cost-effective carbon sources, reducing production costs and aligning with circular bioeconomy principles. Advances in strain engineering, synthetic biology, and omics-guided optimization have significantly improved BC yield and functionalization, enabling applications in food packaging, biomedicine, cosmetics, and advanced biocomposites. Process innovations, including tailored pretreatments, adaptive evolution, and specialized bioreactor designs, further enhance scalability and product quality. The integration of BC production into circular bioeconomy models not only diverts biomass from landfills but also replaces petroleum-based materials, contributing to environmental protection and resource efficiency. This review underscores BC’s potential as a sustainable biomaterial and identifies research directions for overcoming current bottlenecks in industrial-scale implementation. Full article

The pomegranate, a widely consumed fruit, produces large quantities of waste, mainly from its peel. Pomegranate peels (PPs) contain high amounts of antioxidant compounds, such as polyphenols, flavonoids, and anthocyanins, which can be isolated from them and used for the benefit of humans and the environment. In the present work, a study of recovery of these compounds by ultrasound-assisted extraction (UAE) was carried out, whose parameters were optimized. The optimal results were a total polyphenol content of 195.55 mg gallic acid equivalents/g, total flavonoid content of 74.78 mg rutin equivalents/g, total anthocyanin content of 992.87 μg cyanidin 3-O-glucoside equivalents/g, and ascorbic acid content of 15.68 mg/g, while the antioxidant activity determined through ferric-reducing antioxidant power and DPPH assays was 2366.89 and 1755.17 μmol ascorbic acid equivalents/g, respectively. In parallel, an artificial intelligence (AI)-based framework was developed to model and predict antioxidant and phytochemical responses from UAE parameters. Six machine learning models were implemented on the experimental dataset, with the Random Forest (RF) regressor consistently achieving the best predictive accuracy. Partial dependence analysis revealed ethanol concentration as the dominant factor influencing outcomes, while ultrasonic power and extraction time exerted comparatively minor effects. Although dataset size limited model generalizability, the RF model reproduced experimental outcomes within experimental variability, underscoring its suitability for predictive extraction optimization. These findings demonstrate the complementary role of machine learning in accelerating antioxidant compound recovery research and its potential to guide future industrial-scale applications of AI-assisted extraction. Full article

The utilization of proper fermentation techniques is a widely recognized, efficacious approach in animal husbandry for enhancing the feed quality. However, research on vegetable waste, particularly that of roots, stems, leaves, fruits, and peels, has been rarely reported. To this end, the present study was carried out to examine the impact of vegetable leaf fermentation on growth performance, immune function, antioxidant levels, intestinal morphology, and microbial composition in sheep. Fifty-four male sheep (Oula) with an average age of 6 months and an average body weight of (21.53 ± 2.03) kg were randomly divided into three treatment groups, with six replicates each. The groups were fed with a basal diet (CON), 30% commercial fermented concentrate (CFC), and 30% vegetable leaf fermented concentrate (VFC). The results showed that compared to the CON group, both the commercial fermented concentrate and the vegetable leaf fermented concentrate improved the final weight (8.93%), average daily gain (30.67%), and dry matter intake of the sheep (1.62%). VFC increased the serum T-AOC (34.45%) and significantly increased the activities of serum and liver GSH-PX (10.95%). Meanwhile, the addition of vegetable leaf fermented concentrate increased the levels of serum IgA (63.21%), IgG (73.06%), and IgM (69.41%). VFC increased the villus height of the jejunum by 87.4% and the ileum by 185.5% and improved the villus height/crypt depth (V/C) ratio of the duodenum and ileum. CFC can also increase the villus height of the duodenum and jejunum, but has no effect on the morphology of the ileum. In addition to its other regulatory effects, VFC can further improve the richness and diversity of the rumen microbial community in sheep, with a notable enhancement in the relative abundance of key phyla, including Bacteroidetes, Ascomycota, Zygomycota, Chytridiomycota, and Basidiomycota. At the same time, the relative abundance of Succinivibrio was reduced. It can thus be concluded that the vegetable leaf fermented concentrate improves the growth performance and intestinal health of sheep. Full article

Polyphenols have gained significant attention in recent decades due to their protective role against cancer, diabetes, obesity, osteoporosis, neurodegenerative, and cardiovascular diseases. This study explored the influence of radiation time, microwave power, and sample-to-solvent ratio on the microwave-assisted extraction of polyphenols from Pithecellobium dulce fruit peels. Extraction efficiency, antioxidant activity, and anti-cholesterol activity were optimised using both response surface methodology (RSM) and artificial neural networks combined with a genetic algorithm (ANN-GA). The ANN-GA model exhibited higher predictive accuracy (R² = 0.9805–0.9813) and lower statistical error compared to quadratic RSM models (R² = 0.9566–0.9767). Under optimised conditions, ANN-GA yielded 244.35 mg/g total polyphenols, 92.51% antioxidant activity, and 73.96% anti-cholesterol activity, outperforming RSM (242.35 mg/g, 92.18%, and 73.26%, respectively). These findings demonstrate the scientific novelty of ANN-GA as a more robust and reliable tool than RSM for process optimisation. Moreover, the study highlights the practical application of utilizing P. dulce fruit peels as a low-cost, natural source of health-promoting bioactives. Importantly, this work presents a broader impact by providing a sustainable strategy for waste valorisation into nutraceutical and pharmaceutical products. Full article