Search Results (186)

Gastric cancer remains a leading cause of cancer-related mortality worldwide. Citrus fruits are rich in polyphenols, exerting antioxidant and chemo-preventive activities, and lemon peel represents a valuable source of such bioactive compounds. Previous studies showed that Citrus limon peel extracts (LPE) inhibited the activity of some enzymes of the antioxidant system and reduced the interleukin-6-dependent invasiveness of gastric and colon cancer cells. In the present study, we have investigated the effects of LPE on the human gastric adenocarcinoma AGS and MKN-28 cells and on the activity of a crucial redox enzyme, catalase (CAT). Indeed, LPE significantly reduced the cell viability and clonogenic potential of the gastric cancer cells and induced morphological changes indicative of cytotoxicity. Moreover, LPE modulated the intracellular redox homeostasis by decreasing levels of the hydrogen peroxide-related reactive oxygen species (ROS) while increasing those of superoxide anions and decreasing levels of superoxide dismutases (SODs). Western blotting analysis revealed that LPE downregulated CAT, SOD-1, SOD-2, and monoamine oxidase A (MAO-A) protein expression level in both cell lines. Finally, the extract inhibited CAT activity in a dose-dependent manner (IC₅₀ = 0.008 ± 0.003 mg/mL; K_i = 0.012 ± 0.002 mg/mL). These findings indicate that LPE exerts cytotoxic and redox-modulating effects through the inhibition of antioxidant enzymes and the alteration of ROS balance. Therefore, the agro-industrial by-product LPE could be considered as a promising natural source of polyphenolic compounds with potential applications in the prevention and therapy of gastric cancer. Full article

Objectives: The purpose of this study is to compare the differences between lemon-derived exosome-like nanovesicles (LELNs) stored at −80 °C, −20 °C, and 4 °C for one month and freshly isolated LELNs, in terms of characterization and anti-inflammatory effects on periodontal ligament cells, aiming to identify suitable storage conditions for LELNs. Methods: Nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and micro bicinchoninic acid assay (BCA) were conducted to access the characterization differences. LPS-induced human periodontal ligament cells were used as an in vitro inflammatory model, and the changes in biological functions were examined by qRT-PCR and ELISA. Results: LELNs stored at −80 °C retained the highest particle and protein concentration and showed the least aggregation and heterogeneity in size on TEM images, while the average particle sizes shown by NTA were similar. And LELNs exhibited similar anti-inflammatory effects on periodontal ligament cells after one month of storage at −80 °C, −20 °C, and 4 °C. Conclusions: We found that LELNs can maintain in vitro anti-inflammatory ability when stored at either −80 °C, −20 °C, or 4 °C for one month, while storing at −80 °C maintains the concentration and uniform particle size best. Full article

The Citrus limon (L.) Burm. f. industry suffers significant losses due to fungal diseases. Therefore, this study aimed to evaluate the effectiveness of sodium benzoate (SB) and potassium sorbate (PS) on the incidence of fungal decay and fruit quality when used as preharvest treatments on Fino lemon trees over two consecutive seasons (2021–2023). Lower concentrations of SB and PS (0.1% and 0.5%) applied in one or two treatments successfully controlled fungal decay. On average, SB achieved a greater reduction in decay, ranging from 45% to 60%, compared to PS’s reduction of 25% to 50%. This approach minimised the negative impact on lemon fruit quality, in contrast to the highest doses (more than 1%) and the greatest number of applications (more than three times), which increased lemon susceptibility to decay. Furthermore, lemons treated with 0.5% SB twice enhanced antioxidant systems, showing a 35% increase in total phenolic content in the flavedo at harvest compared to the control. Consequently, the application of 0.5% SB twice at preharvest emerges as a promising and potential alternative to conventional fungicides for effective fungal decay control and maintenance of acceptable lemon quality traits during cold storage. Full article

Mal secco disease (MSD), caused by Plenodomus tracheiphilus, poses a serious threat to Citrus limon production across the Mediterranean Basin. This study investigates the potential of high-resolution WorldView-3 imagery for detecting early-stage MSD symptoms in lemon orchards through the integration of three pansharpening algorithms(Gram–Schmidt, NNDiffuse, and Brovey) with two machine learning classifiers (Random Forest and Support Vector Machine). The Brovey-based fusion combined with Random Forest yielded the best results, achieving 80% overall accuracy, 90% precision, and 84% recall, with high spatial reliability confirmed by 10-fold cross-validation. Spectral analysis revealed that Brovey introduced the largest radiometric deviation, particularly in the NIR band, which nonetheless enhanced class separability between healthy and symptomatic crowns. These findings demonstrate that moderate spectral distortion can be tolerated, or even beneficial, for vegetation disease detection. The proposed workflow—efficient, transferable, and based solely on visible and NIR bands—offers a practical foundation for satellite-driven disease monitoring and precision management in Mediterranean citrus systems. Full article

Vegetation in residential areas plays a crucial role in biodiverse and sustainable cities as it enhances biological diversity, environmental quality, and the human well-being of city residents. However, the distribution of vegetation among these areas is often unequal, leading to disparities in access to its benefits. To promote a more biodiverse and environmentally just city, we investigated how woody plants (trees, shrubs and vines) vary with socioeconomic level in residential streetscapes of Santiago de Chile. Across the city, we sampled woody plants in 120 plots (11 m radius) located in residential streetscapes of three socioeconomic levels: low, medium, and high. A total of 557 woody plants were identified and measured. Of these, only 9.7% corresponded to native species, whereas 90.3% were introduced species. Wealthier residential areas had higher species richness and abundance of woody plants, as well as plants with greater structural size (revealed by height and crown area). In addition, we found that the composition of woody plants differed among socioeconomic levels: Liquidambar styraciflua, Platanus x hispanica, and Pittosporum tobira were more abundant in high socioeconomic areas; Prunus cerasifera, Citrus limon, and Ailanthus altissima were more abundant in medium socioeconomic areas; Robinia pseudoacacia, Acer negundo, and Schinus areira were more abundant in low socioeconomic areas. Our research highlights that woody plant diversity, abundance, structure, and composition vary with socioeconomic level in residential streetscapes. Key insights for reducing these inequalities and achieve a more environmentally just city include: (a) governance and equity-based investment; (b) prioritizing local native species; (c) promoting the use of non-tree woody plants; and (d) empowering communities through capacity building and stewardship. Full article

In the present study, the essential oils (EOs) of peels and leaves from the new limonime lime, ‘Eugene’ hybrid, were analyzed for the first time and compared with those of its parental plants, Citrus latifolia var. latifolia (Persian lime) and Citrus × limon cv. Zambetakis (lemon). This hybrid represents the first successful cross between these two species, exhibiting distinctive features such as aroma and shape. GC-MS analysis identified a total of 30 and 44 metabolites in the hybrid’s peel and leaf EOs, respectively. Limonene was the predominant volatile in both peels and leaves across all genotypes. In the peel EOs, the monoterpenes γ-terpinene, β-pinene, and geranial were among the most abundant compounds. In contrast, the leaf EOs showed differences between genotypes: the hybrid and Persian lime had similar volatile profiles dominated by geranial, neral, and neryl acetate, while β-pinene was only detected in lemon. Additionally, the total phenolic content and DPPH radical scavenging activity of the methanolic extracts of peels and leaves were evaluated, and revealed that lemon extracts were richer in phenolic compounds and with higher antioxidant activity compared to those of hybrid and Persian lime. Overall, the development of improved Greek varieties like the ‘Eugene’ hybrid holds significant potential to enrich the genetic diversity of Greek Citrus germplasm and broaden the commercial portfolio of citrus fruits with unique and desirable traits. Full article

The COVID-19 pandemic has renewed global interest in medicinal plants as accessible sources of prophylactic and supportive therapies. Ethnobotanical research provides an important foundation for developing plant-based medicines with preventive and therapeutic potential. This study aimed (1) to investigate the distribution and indications for the use of medicinal plants in the prevention and relief of COVID-19-related symptoms among the Bulgarian population, and (2) to identify culturally significant species with potential for further development as antiviral agents. A total of 513 respondents from different regions and demographic groups in Bulgaria were interviewed. Their knowledge regarding the use of medicinal plants for COVID-19 prevention or treatment was quantitatively assessed using ethnobotanical indices: relative frequency of citation (RFC), informant consensus factor (FIC), fidelity level (FL), and use value (UV). Participants reported 45 species belonging to 43 genera and 23 families. The highest RFC and UVs were recorded for Matricaria chamomilla L., Tilia sp., Thymus vulgaris L., Zingiber officinale Roscoe, Mentha sp., Citrus x limon (L.) Osbeck, Rosa canina L., and Sideritis scardica Griseb. Culturally significant species identified were Thymus vulgaris L., Matricaria chamomilla L., Tilia sp., Mentha sp., Sideritis scardica Griseb, Zingiber officinale Roscoe, and Citrus x limon (L.) Osbeck. This ethnobotanical survey in Bulgaria documents culturally important medicinal plants that may have potential applications in prophylaxis and complementary therapy for COVID-19. Full article

Citrus fruit cultivation and processing are constantly rising due to the increasing market demand and diverse utilization potentials. This generates large quantities of residues, predominantly composed of citrus peels. This study aimed to evaluate six different citrus peels using rapid and/or nondestructive instrumental analytical techniques such as ATR-FTIR spectroscopy, spectrophotometric assays, image textural analysis and physicochemical parameter determination. Image textural features managed to discriminate citrus peels based on their structure uniformity, which was found increased in lemon (C. limon) and yellow grapefruit (C. paradisi), whereas clementine (C. clementina) and red grapefruit (C. paradisi) images exhibited an increased non-uniformity of the structure. Physicochemical parameters provided insights into the quality characteristics of citrus peels, while their high ascorbic acid content seems to enhance their antioxidant activity. The obtained results from phenolic and flavonoid content determination indicated a high concentration of polyphenols in the peels, which is aligned with the ATR-FTIR spectra absorption bands. Furthermore, the spectrophotometric assays’ strong correlation suggests that the antioxidant activity of citrus peels is mainly attributed to polyphenols. Ultimately, a chemometric model was employed to provide a comprehensive understanding of the analytical methods’ interactions. Hence, citrus peels’ significant biochemical and, consequently, economic value can be highlighted, underscoring the importance of further research. Full article

The growing demand for fresh-cut fruit requires innovative preservation strategies to counteract rapid quality deterioration, particularly in lemon (Citrus limon (L.) Burm. f.), which is highly susceptible to flesh browning and loss of sensory traits. Manna, a natural exudate obtained from Fraxinus angustifolia, is traditionally used in the Mediterranean area and is known to be rich in bioactive compounds such as polyphenols, minerals (e.g., calcium), and antioxidants. This study aimed to evaluate the effectiveness of manna as a natural preservative on fresh-cut lemon slices (cv. Zagara Bianca) from two different flowerings, primofiore (yellow fruit) and verdello (green fruit), harvested at the same time. Treatments with different manna solutions (5%, 10%, and 15%) were applied, and physicochemical parameters, nutraceutical content, and sensory traits (flavor and acidity perception) were evaluated at harvest and after 3, 6, and 12 days of storage at 5 °C with 85% RH. The results showed distinct effects depending on the maturity stage, but in all cases, manna treatments modulated the respiration rate, reduced weight loss, modified acidity perception, and improved nutraceutical content. In green lemon slices, treatment with 15% manna helped to maintain nutraceutical stability, sustained antioxidant activity, and reduced quality degradation, ensuring a balanced lemon flavor perception. In yellow lemon slices, treatment with 15% manna led to an increase in total soluble solids and a modified taste perception, resulting in a less pronounced freshness compared with the control. Overall, manna proved to be a natural coadjuvant capable of limiting oxidative processes and slowing tissue senescence, while simultaneously enhancing the nutraceutical properties of fresh-cut lemon slices. Full article

Carbon quantum dots (CQDs) are photoluminescent nanomaterials (<10 nm) with excellent hydrophilicity, biocompatibility, and low cytotoxicity, making them attractive for biological applications. However, their use in aquaculture nutrition has remained largely unexplored. This study investigated the effects of dietary CQDs on zebrafish (Danio rerio), a model organism with approximately 70% genetic homology with humans. CQDs were synthesized hydrothermally from unripe Citrus limon and characterized by UV–visible (UV-Vis) spectroscopy, UV–vis transillumination, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), Fourier-transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectroscopy. Zebrafish were fed diets containing varying CQD concentrations, and growth performance, condition factor (K), hematological parameters, enzymatic activity, and tissue morphology were assessed. Feeds supplemented with 2 mL CQDs produced significant improvements in growth and biochemical indicators without adverse effects. Hematological and enzymatic profiles remained within normal ranges, and histological examination revealed no morphological abnormalities, indicating the absence of toxicity. These findings suggest that citrus-derived CQDs can enhance zebrafish growth and maintain physiological health, thereby supporting their potential as safe functional feed additives in aquaculture. This approach may open new opportunities for the application of CQDs in sustainable fish farming and the broader food industry. Full article

The genus Citrus consists of Tangerines (Citrus × reticulata), Mandarins (Citrus × reticulata), Oranges (Citrus × sinensis), Grapefruits (Citrus maxima), Lemons (Citrus × limon), and other citrus fruits. This study investigated the effects of 74 different citrus species and harvesting time on the quality of citrus dark tea using Hubei green brick tea as the raw material. Oranges (Citrus × sinensis) were found to outperform other species in improving the quality of citrus dark tea. Additionally, the impact of orange harvesting time (August to December) on the quality of orange dark tea was investigated by using the Peach leaf orange with the highest sensory score as the subject of the study. Results revealed that harvesting time can considerably impact the flavor quality of orange dark tea, but not its infusion color or scent. Specifically, the orange dark tea processed with September-harvested Peach leaf orange exhibited a strong fruity scent, a sweet and smooth flavor, and a harmonious tea and fruit aroma. With the delay of harvesting time, a downtrend was observed in the content of soluble proteins, flavonoids, hesperidin, synephrine, and limonin, as well as total volatile components, with the largest decrease in synephrine and flavonoids. However, the polysaccharide content increased in the peel of Peach leaf orange. Functional analysis revealed that the delay of harvesting time can diminish the inhibitory capacity of orange-dark tea on α-glucosidase and α-amylase. Organoleptic quality and physiological activity analysis demonstrated September as the optimal time for harvesting Peach leaf oranges for processing orange dark tea. Full article

Halophilic isolates were screened to mitigate postharvest losses caused by citrus canker disease in lemon fruits. Among all isolates, SWIS03, isolated from the Sambhar Salt Lake in Rajasthan, India, exhibited the highest exopolysaccharide production, with good stability and antibacterial activity against Xanthomonas citri. Isolate SWIS03 was identified as halophilic Bacillus licheniformis DET601. It produced a very high EPS content in optimized sterilized seawater-based minimal media fortified with 2.5% sucrose and 0.3% beef extract, which was purified through repeated deproteinization and Sephadex G-75 chromatography. HPTLC analysis of composition check indicated the presence of glucose, mannose, and galactose. FTIR analysis also confirmed the presence of sugar and bound water, as well as the presence of hydroxyl, amine, amide, and methyl groups. Rheological characterization revealed a pseudoplastic nature, making it suitable for uniform coating. EPS was reported to have bioactive properties, including antioxidant activity (84.7 ± 1.75% DPPH scavenging potential), antimicrobial activity against human pathogens, and a noncytotoxic nature, which are essential for use in edible coatings. The effect of EPS coating formulation on healthy lemon fruits resulted in shelf-life extension of up to 26.6 ± 1.14 days and 18.0 ± 1.41 days at 4 °C and 30 °C in coated lemons, respectively, as demonstrated by physiological parameters such as % weight loss, firmness, titratable acidity, and shelf life of lemons. Also, EPS coating preserved the quality of fruits in terms of phenolic compounds and Vitamin C content, and reduced lipid peroxidation during storage. Biocontrol potential of halophilic EPS coating on lemon fruits revealed an 86.50% and 68.64% reduction in % disease incidence compared to uncoated fruits at 4 °C and 30 °C, respectively. Similarly, a significantly lower disease incidence (46.80% at 4 °C and 67.03% at 30 °C) was also reported compared to paraffin-coated (positive control) lemons. Consequently, halophilic Bacillus licheniformis DET601 EPS is an effective coating material for citrus fruits to prevent canker disease in post-harvest settings for agricultural and food industry applications. Full article

Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus (CLas), is the most devastating disease threatening global citrus production. Although no commercial citrus varieties exhibit complete HLB resistance, genotype-specific tolerance variations remain underexplored. This study conducted a comparative transcriptomic profiling of six commercially citrus cultivars in South China, four susceptible cultivars (C. reticulata cv. Tankan, Gongkan, Shatangju, and C. sinensis Osbeck cv. Newhall), and two tolerant cultivars (C. limon cv. Eureka; C. maxima cv Guanxi Yu) to dissect molecular mechanisms underlying HLB responses. Comparative transcriptomic analyses revealed extensive transcriptional reprogramming, with tolerant cultivars exhibiting fewer differentially expressed genes (DEGs) and targeted defense activation compared to susceptible genotypes. The key findings highlighted the genotype-specific regulation of starch metabolism, where β-amylase 3 (BAM3) was uniquely upregulated in tolerant varieties, potentially mitigating starch accumulation. Immune signaling diverged significantly: tolerant cultivars activated pattern-triggered immunity (PTI) via receptor-like kinases (FLS2) and suppressed ROS-associated RBOH genes, while susceptible genotypes showed the hyperactivation of ethylene signaling and oxidative stress pathways. Cell wall remodeling in susceptible cultivars involved upregulated xyloglucan endotransglucosylases (XTH), contrasting with pectin methylesterase induction in tolerant Eureka lemon for structural reinforcement. Phytohormonal dynamics revealed SA-mediated defense and NPR3/4 suppression in Eureka lemon, whereas susceptible cultivars prioritized ethylene/JA pathways. These findings delineate genotype-specific strategies in citrus–CLas interactions, identifying BAM3, FLS2, and cell wall modifiers as critical targets for breeding HLB-resistant cultivars through molecular-assisted selection. This study provides a foundational framework for understanding host–pathogen dynamics and advancing citrus immunity engineering. Full article

This research analyzes the innovative development of carnauba wax coatings enriched with essential oils (EOs: lemon, orange, grapefruit, clove, oregano, and cinnamon) or fruit by-products (FBPs: avocado, tomato, carrot, orange, lemon, and grapefruit) to improve postharvest preservation of organic oranges and lemons. Six EOs and six FBPs were evaluated for total phenolic content (TPC) and in vitro antifungal activity against Penicillium digitatum. Based on results, grapefruit, oregano, and clove EOs were selected for lemons, while avocado, orange, and grapefruit FBPs were selected for oranges. An in vivo test at 20 °C for 15 days with carnauba wax coatings assessed antifungal performance. Clove EO and avocado FBP showed strong in vitro inhibition and consistent hyphal suppression (~100 and ~82%, respectively). In vivo, coatings with grapefruit EO and avocado FBP significantly reduced fungal decay and sporulation (~75%) in lemons and oranges, respectively. Coated fruits also retained weight losses by ~25% compared to uncoated ones. These findings suggest that phenolic-rich natural extracts, especially from agro-industrial residues like avocado peels, offer a promising and sustainable strategy for postharvest citrus disease control. Further studies should test coating effectiveness in large-scale trials under refrigeration combined with other preservation strategies. Full article

Dried lemon slices (LSs) have become increasingly popular as a healthful beverage when infused in hot water. This study examined the effects of freeze drying (FD), hot air drying (HAD), heat pump drying (HPD), and far-infrared drying (FID) on the quality of dried LSs and their brewed beverages. The results show that FD-LSs and their corresponding beverages have the most appealing appearance and maximum levels of ascorbic acid (2.47 and 0.80 mg/g, respectively), synephrine (8.15 and 0.94 mg/g, respectively), and the overwhelming majority of natural and available phenolic compounds, as well as the strongest antioxidant activity, although numerous volatile compounds in FD-LSs were in the lowest abundances. HPD-LSs exhibited similar trends to FD-LSs but contained the peak concentrations of limonene (2258.87 μg/g), γ-terpinene (704.19 μg/g), β-pinene (502.92 μg/g), and α-pinene (188.91 μg/g), which were the four most abundant volatile compounds in dried LSs. Additionally, active ingredients in HPD-LSs generally featured relative high levels of available amounts. In contrast, HAD- and FID-LSs typically displayed unfavorable coloration and low retention levels of natural and available active ingredients. Consequently, FD and HPD demonstrate superior suitability for the commercial-scale production of dried LSs. Full article