Search Results (66)

There is a high demand for the development of new carriers for pharmaceutical forms for human, veterinary, and animal-feeding use. One of the solutions might be bioactive compound-loading pellets for animal forage. The aim of the work was to assess the physical and sensory properties of forage with the addition of onion peel and off-spec onions as a source of quercetin. The feed was prepared using an expanding process (thermal–mechanical expanding process). Quercetin content was evaluated in raw onion and in final-product feed mixture samples (before and after expanding, and pelleting). The obtained feed was subjected to sensory analysis, testing for expanded pellet uniformity, water absorption index (WAI), the angle of a slide, and antioxidant activity. The results confirmed a high recovery of the quercetin after the expanding process (approximately 80%), and a significantly reduced intensity of onion odor, which was confirmed compared to the non-expanded onion, which is beneficial. Furthermore, digital and optical microscopy were applied for structure analysis. Microscopic imaging results confirmed that the onion structures were visible in the whole length of feed material and analyzed cross-sections. The results can be an introduction to further research on developing products that use the expanding and pelleting process to exploit the peel and off-spec onions, as well as other waste raw materials. Full article

Synthetic plastic pollution represents a major global concern, driving the search for sustainable and biodegradable packaging alternatives. However, many biodegradable plastics suffer from inadequate mechanical performance. This study aimed to develop a biodegradable film based on cassava starch, incorporating onion peel powder (OPP), a byproduct rich in quercetin derivatives, as a reinforcing agent and plasticized with crude glycerol. A Central Composite Design (CCD), implemented using Minitab 19, was employed to investigate the effects of starch (60–80%) and OPP (0–40%) content on the mechanical properties and biodegradability of the resulting bioplastics. Three optimized formulations were identified according to specific performance criteria. The first formulation, containing 72.07% starch and 21.06% OPP, was optimized for maximum tensile strength while maintaining target values for elongation and biodegradability. The second, composed of 77.28% starch and 37.69% OPP, was optimized to enhance tensile strength and biodegradability while minimizing elongation. The third formulation, with 84.56% starch and 27.74% OPP, aimed to achieve a balanced optimization of tensile strength, elongation, and biodegradability. After a 30-day soil burial test, these formulations exhibited weight loss percentages of 31.86%, 29.12%, and 29.02%, respectively, confirming their biodegradability. This study optimized the mechanical and biodegradability properties of cassava starch-based bioplastics using statistical modeling. The optimized formulations show potential for application in sustainable food packaging. Full article

In this study, we evaluated the effect of onion peel extract (OPE), which is rich in phenolics and flavonoids, on the performance of high-gluten wheat flour and bread quality to meet consumer demand for functional bakery products. The addition levels of OPE were set at 0%, 0.25%, 0.5%, 0.75% and 1% (w/w), respectively, to analyze their effects on water/oil absorption capacity, falling number, and rheological properties (farinographic properties, tensile properties, dynamic rheological properties and gelatinization characteristics) of dough, as well as bread quality (antioxidant activity, texture, microstructure, specific volume and sensory evaluation). When the OPE addition level was 0.25% and 0.5%, the dough’s oil absorption capacity, farinographic properties, tensile properties, dynamic rheological properties, and gelatinization characteristics were all improved. Correspondingly, a more compact and ordered microstructure was observed in the dough. It was found that total phenolic content, total flavonoid content, and antioxidant capacity of bread significantly increased with the increase in the OPE addition level (p < 0.05). The texture analysis of the bread showed that the addition of OPE reduces the hardness and chewiness of bread, indicating that the texture of bread was easily accepted by consumers. In the sensory evaluation, when the addition level of OPE was 0.5%, the color and flavor of bread were improved, and the overall acceptability was relatively high. In conclusion, OPE has improved the texture characteristics and nutritional value of bread. It is recommended that the addition level of OPE in high-gluten wheat flour dough and bread be below 0.5%. Full article

Polyphenol-rich extracts derived from agricultural by-products exhibit promising antiviral properties. This study evaluated the antiviral potential of extracts from red onion peels, vineyard prunings, olive prunings and chicory leaves against human coronavirus HuCoV-229E. Subcritical water extraction and resin adsorption techniques were applied to produce the extracts. The extracts were further characterised for their bioactive content, and three out of four extracts showed a high polyphenol content (>200 mg/g). The antiviral activity was assessed through viral infectivity and replication inhibition assays in human MRC-5 host cells. The results indicate that chicory leaf and red onion peel extracts demonstrated significant antiviral effects, with effective concentrations (EC₅₀) of 61.43 µg/mL and 10.1 µg/mL, respectively. Olive pruning extract exhibited moderate activity, while vineyard pruning extract showed limited efficacy. These findings suggest that polyphenol-rich agricultural by-products could serve as sustainable sources for antiviral agents, warranting further investigation into their mechanisms of action and potential applications against other coronaviruses, including SARS-CoV-2. Full article

Onions (Allium cepa L.) are widely consumed worldwide and are recognized for their high content of bioactive compounds with potential health benefits. This study investigates the nutritional and phytochemical properties of three onion varieties—Tropea red onion, red onion, and yellow onion—analyzed in their whole form as well as in their peel and pulp. An innovative drying system was employed to assess its impact on the retention of bioactive compounds. The results highlight significant differences in nutrient composition among varieties and onion parts. The peel exhibited the highest concentrations of proteins, phenolic compounds, flavonoids, and antioxidants, followed by the whole onion and pulp. Tropea red onion stood out for its superior antioxidant capacity, vitamin C content, and phenolic acid levels, reinforcing its potential for functional food applications. This study also revealed that mineral content, particularly calcium, potassium, and sulfates, varied across onion varieties, influencing their nutritional and health-promoting properties. These findings support the valorization of onion byproducts for their bioactive potential and sustainability in the food industry. The data emphasize the need for further research on innovative processing techniques that enhance the bioavailability and effectiveness of onion-derived health-promoting compounds. Full article

Enteric greenhouse gas (GHG) emissions represent a major challenge in livestock production, contributing significantly to global methane output. Various strategies have been explored to mitigate these emissions, including dietary modifications, feed additives, and genetic improvements. In the present study, the focus was on onion peel (OP), a byproduct of the onion processing industry that has shown promise as a natural feed supplement with potential methane-reducing properties. We evaluated the effect of different inclusion levels of OP at 2.5% (OP2.5), 5% (OP5), 7.5% (OP7.5), and 10% (OP10) on the in vitro fermentation of two diets: a total mixed ration referred to as high concentrate (HC), and corn silage referred to as high forage (HF). A 48 h batch culture experiment using a 2 × 3 × 5 factorial arrangement was conducted to assess total gas production (GP), methane (CH₄), carbon dioxide (CO₂), ammonia (NH₃), and hydrogen sulfide (H₂S) concentrations, and nutrient degradability. Measurements were taken at 6 h, 24 h, and 48 h of incubation. Significant additive × diet interactions were observed for most of the parameters. The HC diet produced more gas but less CH₄, CO₂, NH₃, and H₂S compared to the HF diet (p < 0.05). At 24 h of incubation, the OP at all levels increased CH₄, CO₂, NH₃, and H₂S concentrations in the HF diet (p < 0.05). The OP2.5 treatment had the lowest (quadratic effect, p < 0.05) degradable dry matter (dDM) in the HC diet, while the OP linearly (p < 0.001) increased degradable acid detergent fiber (dADF) in both diets. The lowest total volatile fatty acids (VFA) and acetate (quadratic effect, p = 0.027) were observed with the OP5 treatment in the HC diet, while OP5, OP7.5, and OP10 had lower total VFA concentration in the HC diet. At 48 h of incubation, the OP7.5 treatment increased (p < 0.05) GP and CH₄ and CO₂ production in the HC diet. However, the OP5 treatment had the lowest CH₄ production (quadratic effect, p = 0.027) in the HF diet. The highest dDM was observed with OP7.5 treatment (quadratic effect, p = 0.038) in the HC diet with lower values noted at different inclusion levels in the HF diet. Inclusion of OP had no effect on total VFA, and individual VFA in both diets. In conclusion, OP supplementation is more suitable for HF diets than HC diets. A 5% inclusion level is recommended to decrease ruminal CH₄production and improve nutrient degradability. Full article

The bioactive components present in onion peel powder are a promising factor in preventing/treating obesity. Overweight/obesity causes metabolic changes, which can lead to leptin resistance in the central nervous system (CNS) and, thus, to structural and functional changes in the brain. Objectives: The presented study focused on evaluating the influence of a diet supplemented with onion peel powder on the immunoexpression of leptin receptors (LepRs) in the hippocampus in obese rats and the potential anti-obesity role of the onion in the brain. Methods: To induce obesity, the animals were given a high-energy chow containing lard and sucrose. Onion skin powder was used to modify the standard and high-energy diets (10.5 g per rat/week) of Wistar rats in a 14-week experiment followed by a brain IHC study. Results: The effect of the onion diet on the expression of neuronal LepRs and astrocytes in the hippocampus was analyzed. Obese animals receiving onion in the diet showed significant growth in the average number of immunoreactive LepR (LepR-IR) neurons (p = 0.00108) and their average size (p = 0.00168) in the CA1 field of the hippocampus. Meanwhile, in obese rats not given onion peel powder, a significant increase in the average density of astrocytes was observed (p < 0.0001). Conclusions: The increased density of astrocytes in the hippocampus of obese animals can probably have a beneficial effect on brain changes in overweight individuals. The inclusion of onion in the diet of overweight/obese individuals may lead to increased hippocampal neuroplasticity, manifested by changes in the immunoexpression of LepRs. It can be speculated that the observed changes have a protective effect on the CNS structures during obesity, but this undoubtedly requires further research. Full article

This study provides a comprehensive analysis of the composition of onion peels, tomato peels, and pistachio green hulls, with a focus on their structural and bioactive compounds. Onion peels, regardless of cultivar, were found to be rich in quercetin and its derivatives, along with other flavonoids and pectin. Tomato peels emerged as a notable source of naringenin (0.52 mg/g in ethanol extract) and rutin (0.24 mg/g in water extract) and showed an unexpectedly high lignin content, comprising nearly 50% of their structural components. Pistachio green hulls demonstrated a high extractive content (63.4 g/100 g), 73% of which were water-soluble. Protocatechuic acid, rutin, and quercetin derivatives were the dominant phenolic compounds in the water extract, while luteolin was most abundant in the ethanol extract. Regarding structural composition, tomato peels and pistachio green hulls shared similarities, exhibiting a high lignin content (53.4% and 33.8%, respectively) and uronic acids (10–15%). In contrast, onion peels were characterized by high levels of glucans (around 38%) and galacturonic acid (33%). The insights from this study pave the way for the design of sustainable and efficient extraction processes, enabling the sequential recovery of valuable bioactive compounds and promoting the valorization of these agro-industrial by-products. Additionally, onion and tomato peels were evaluated as sources of pectin using two extraction methods: conventional acid water extraction and subcritical water extraction. The results revealed significant differences in the pectin composition (53–68% galacturonic acid) and degree of esterification (79–92%) compared to commercial pectin (72.8% galacturonic acid and 68% esterification), highlighting the influence of the raw material and extraction method on the final properties of pectin. Full article

In this study, polyphenols in the crude extract (CE) from red onion peel were recovered by macroporous resin, and their antioxidant and anti-inflammatory activities were evaluated. Among the four resins screened (SP850, XAD2, XAD7HP, and XAD16N), XAD7HP showed the highest desorption and recovery ratios, and it was used to optimize polyphenol recovery through single-factor experiments. The optimal conditions were established as 1 g resin, pH 4, 25 °C, 7 h for adsorption, followed by desorption with 70% ethanol for 1 h at 25 °C. These conditions achieved 85.00% adsorption ratio, 87.10% desorption ratio, and 20.9% yield of the macroporous resin-recovered extract (MRE) from the CE. HPLC analysis revealed that rosmarinic acid, quercetin, and myricetin were major compounds in the MRE, with the content of these compounds higher (about 7-fold) compared to the CE, confirming enhanced recovery of polyphenols by macroporous resin. Moreover, FT-IR and ¹H-NMR analysis confirmed the successful recovery of these polyphenol compounds in the MRE. Furthermore, the MRE displayed significantly improved antioxidant activities (DPPH, ABTS, and FRAP) and anti-inflammatory activities (inhibition of nitric oxide synthesis and reactive oxygen species production) compared to the CE. In summary, our findings suggest that macroporous resin can effectively recover polyphenol compounds from red onion peel extract and enhance their biological activities. Full article

Food waste and food waste by-products have gained considerable attention in recent years. Based on the principles of circular economy, these materials can be used for the preparation of novel and biodegradable packaging materials for food preservation. Among the matrices that have been well exploited, poly-lactic acid (PLA) comprises a key material to be fortified with food waste by-products, as shown by numerous studies in the recent literature. In this context, the aim of the present review was to provide an overview of the literature on the most recent trends in the use of PLA and food waste by-products to prepare films for the shelf-life extension of foods of animal or plant origin. The results showed that the use of PLA packaging films fortified with food waste by-products of plant or animal origin has greatly expanded in the last 20 years. The application of these novel packaging materials to foods has led to considerable shelf-life extension and stability. However, there is still a gap in the use of specific food waste by-products of plant origin, such as peels, seeds, or gels (i.e., onion peels, grape seed extract, grape pomace, prickly pear cladode gel) or animal food waste by-products (i.e., whey, collagen, gelatin), to prepare PLA-based packaging films. The present review, which comprises the thematic issue of an ongoing doctoral study, examines trends and challenges with regard to this topic that have not been extensively studied. Full article

The present article focuses on the characterization of the new biocomposites of poly(butylene succinate) (PBS) with fillers of plant origin such as onion peels (OP) and durum wheat bran WB (Triricum durum) subjected to composting and artificial aging. The susceptibility to fungal growth, cytotoxicity and antibacterial properties were also examined. The biodegradation of the samples was investigated under normalized conditions simulating an intensive aerobic composting process. It was shown that the tested natural fillers significantly accelerate the biodegradation process of the composition (after 90 days mass loss of PBS 7%) and that the samples with WB degrade much faster (corresponding mass loss 86%) than those containing OP (corresponding mass loss 21%). The remains of the samples after composting were subjected to chemical structure analysis (FTIR), and their thermal properties were determined using differential scanning calorimetry (DSC). It was shown that the degree of crystallinity of PBS and composites increased with the increasing time of composting. In the case of pure PBS, this increase was a maximum of 31.5%, for biocomposite with OP 31.1% and for those containing WB 21.2%. FTIR results showed that cleavage of polymer chains by hydrolysis took place during composting. The tested samples were also subjected to artificial aging under conditions simulating solar radiation and were sprayed with water. After artificial aging, the significant changes in the color of the samples as well as the porosity of their surface was noted, which was mainly due to the effect of photodegradation of both the used OP and WB fillers. Additionally, FTIR analysis indicated that samples were degraded by photooxidation processes. The ability of fungi to grow on the surface of the samples was also tested. The results demonstrate the possibility of using the developed biocomposite materials as a carbon source for the growth of fungi. The antibacterial tests showed that samples containing OP exhibited strong antibacterial properties regardless of their wt.% content. Additionally, a cytotoxicity test was performed on a BJ cell line, demonstrating that none of the tested biocomposites were cytotoxic. Moreover, those with the addition of WB statistically significantly supported the viability of both fibroblast and bacteria cells, showing their biological safety but lack of antibacterial activity. Full article

This study investigated the survival and growth of Salmonella in onion extracts and bulbs. The inhibition or retardation of Salmonella growth by extracts of red, white, and yellow onions was tested against the onion germplasm and exposure to different light spectra during curing. Separately, survival of Salmonella Newport was tested on red, white, and yellow onion bulbs on the external and internal onion layers with a syringe and needle. Onions exposed to blue, red, and white LED light during curing produced extracts with variable antimicrobial effects (p < 0.05), with those exposed to blue light showing the strongest inhibitory effect on red and white onions only. In survival studies, Salmonella inoculated on the outer scale was reduced by 1.2, >2.7, and >2.4 logs on red, white, and yellow onions, respectively, within 3 days, whereas it grew by 2.4, 2.6, and 2.8 logs inside red, white, and yellow onion bulbs, respectively, over 18 days. In separate trials, the outer layer again did not support the survival of Salmonella Newport. The a_w increased significantly from 0.51 to 0.58 in the outer scales and 0.96 to 0.98 for the fourth inner scales. Despite being rich in antimicrobial polyphenols, tissue integrity and water content may still promote Salmonella growth in onions. Full article

This paper presented an extended double-subsegment discrete Fourier transform (DS-DFT) algorithm as a tool for the fine spectral estimation of high-noise environments, which was previously effective in low-noise scenarios, and as such, its application to the analysis of noisy signals observed by a satellite-based interferometer was investigated. The observation of satellite-borne Doppler asymmetric spatial heterodyne spectroscopy (DASH) was first simulated to obtain the signals of low- and high-noise levels; then, a practical criterion to classify noise levels in the interferograms based on the DS-DFT results was introduced and validated by calculating the SNR. For high-noise signals, DS-DFT remains robust by employing phase differences and amplitude ratios for fine frequency estimation. Full article

The use of biological methods to control plant diseases has garnered attention due to their eco-friendly and economically viable nature. Trichoderma spp. are the most ubiquitous fungal saprophytes that can often grow as opportunistic symbionts, are eco-friendly, and are not reported to exert any environmental hazard. Soil-borne pathogens can significantly impact the yield of chilli and tomato crops. The study was conducted to explore the impact of various salts (NaCl, MgCl₂, CaCl₂, and KCl) and their concentrations (1%, 5%, 10%, and 15%) on the mycelial growth and sporulation of Trichoderma viride followed by its mass multiplication on diverse organic substrates like wheat seeds, wheat husks, mungbean seeds, maize seeds, rice seeds, pea seeds, sorghum seeds, banana peel, apple peel, pomegranate peel, citrus peel, tomato waste, chilli waste, spinach waste, cabbage waste, potato peel, onion peel, cucumber peel, carrot peel, used black tea leaves, used green tea leaves, poultry waste, and cow and goat dung. The study assessed the biocontrol potential of Trichoderma viride against important soil-borne pathogens in chilli (Pythium aphanidermatum, Phytophthora capsici, and Fusarium oxysporum) and tomato (Pythium aphanidermatum, Phytophthora infestans, and F. oxysporum) cropping in the pot and field experiments using saline and alkaline soils. Seed treatment with T. viride significantly enhanced the germination rates of both chilli and tomato crops, with sorghum being the most conducive substrate for mass-multiplying T. viride. The results revealed that lower salt concentrations minimally affected T. viride growth, while higher concentrations hampered both growth and sporulation. Optimal disease control and plant height were observed at a 20 mg concentration of T. viride, consequently applied in vivo using various application methods, i.e., seed treatment, root dip, irrigation, and mixed treatments (all the methods like seed treatment, root dip method, and irrigation method applied together) to manage soil-borne pathogens. Particularly, T. viride application through irrigation and mixed treatments demonstrated strong efficacy. These findings underscore the potential of T. viride application in saline and alkaline soils to manage soil-borne pathogens like Pythium, Phytophthora spp., and Fusarium spp. This study lays the foundation for the practical application of biocontrol agents, like T. viride, in Pakistani agricultural conditions. Moreover, there is a need for further exploration into the genetic mechanisms involved in disease inhibition and plant growth promotion, along with understanding the impact of T. viride on the metabolic pathways of host plants. Full article

The current study evaluated the effect of combining mannan oligosaccharide (MOS) and onion peel (OP) on ruminal in vitro total gas (GP), greenhouse gas emissions, dry matter and fiber fraction digestibility, partitioning factor (PF₂₄; mg degradable DM per mL gas), microbial mass, and volatile fatty acids using two dietary substrates: high forage (HF) and high concentrate (HC) diets. The study was arranged as a 2 × 2 × 6 factorial design with two dietary substrates, two time points (6 and 24 h), and six treatments. The treatments included a control group with no MOS or OP administration and groups administered with 2% of a mixture containing MOS and OP in the following ratios: 1:0 (MOS), 0:1 (OP), 1:1 (MOS:OP), 1:2 (MOS:2OP), and 1:3 (MOS:3OP). No significant diet × treatment interactions were observed for any of the measured parameters. However, treatments decreased (p < 0.05) the undegraded portion of HC, and treatment × substrate interactions were significant (p < 0.05) for PF₂₄ and microbial mass. The treatments in the HC diet produced higher GP (p < 0.001) at 6 h compared to the treatments in the HF diet. Administration of MOS:2OP to the HC diet increased GP at 24 h of incubation, while the lowest GP was observed with the OP in the HF diet. The administration of MOS, OP, and MOS:2OP to the HC diet decreased methane production at 24 h of incubation. Additionally, MOS:2OP and MOS:3OP increased (p < 0.001) degradable acid detergent fiber (dADF) in the HC diet at 6 h of incubation. Both OP and MOS:3OP decreased the degradability of acid detergent lignin in the HC diet (p < 0.001). The OP also resulted in the lowest DM disappearance (p < 0.001) at 24 h of incubation in the HF diet, while the MOS:3OP had the highest dADF. At the end of incubation, the highest productions of total volatile fatty acids and acetate were observed (p = 0.002) with the MOS:OP administration in the HC diet, whereas the lowest values were observed with MOS and OP administration to the HF diet. The inclusion of mannan oligosaccharide and onion peel combinations as additives improved substrate (HC and HF) fermentation, leading to higher GP and volatile fatty production, and modulated fiber degradability by improving the breakdown of acid detergent fiber and acid detergent lignin. Full article