Search Results (127)

The drying process plays a crucial role in enhancing the shelf life of food products by reducing moisture content. As climate change contributes to rising temperatures, alternative drying methods, such as solar drying, offer promising solutions for sustainable food preservation. This study investigates the solar drying of eggplant (Solanum melongena L.) slices, with a focus on the effect of salting pretreatment on drying efficiency. Eggplant slices were subjected to salting pretreatment for partial moisture removal prior to drying. Drying kinetics were monitored to construct the characteristic drying curve. The dried eggplant slices were evaluated for their proximate composition and rehydration capacity, as well as textural and thermal properties. The results showed that salting pretreatment significantly enhanced the solar drying process by accelerating moisture removal. Notably, water activity (aw) decreased significantly from 0.978 to 0.554 for the control sample and to 0.534 for the saltedsample. Significant differences were observed between the dried and salted dried slices, particularly in rehydration capacity, which decreased following salting. Additionally, the salted dried samples showedreductions in protein, carbohydrate, and potassium contents. In contrast, ash content and hardness increased as a result ofosmotic pretreatment. These findings suggest that while dry salting pretreatment effectively reduces solar drying time, it may adversely affect several nutritional and textural properties. Full article

Salt stress presents a major environmental constraint to global agricultural productivity and crop yield stability. Eggplant (Solanum melongena L.) is one of the most extensively cultivated Solanaceae crops worldwide, and the characterization of its germplasm for salt tolerance is essential to develop breeding programs to target its abiotic stress resilience. In this study, 200 mmol/L NaCl was identified as the initial screening concentration for the discrimination of salt tolerance levels in eggplant seedlings. Salt tolerance indices derived from 13 descriptors, including the plant height, stem diameter, and leaf number, were used to evaluate 165 germplasm resources (108 inbred lines and 57 commercial cultivars). These 165 germplasms were grouped into five groups, and six highly tolerant and eight highly sensitive germplasms were identified. Importantly, a stepwise multiple linear regression model incorporating the root surface area, leaf number, leaf water content, malondialdehyde content, and stem water content achieved 90.02% predictive accuracy, establishing a high-throughput screening protocol for germplasm selection. This systematic approach provides methodological advancements for precision breeding and identifies key physiological and morphological markers for salt tolerance improvement in eggplant. Full article

Soil salinity is a major constraint on crop cultivation, affecting millions of hectares of land and increasing drastically worldwide. Identifying sources of tolerance within the crops and their wild relatives is imperative. Recently, Solanum dasyphyllum L. has been identified as source of tolerance to drought for eggplant (S. melongena L.). In this article, the potential use of S. dasyphyllum as a source of tolerance to salinity is investigated through the characterization of young plants’ performance under three salt stress treatments, well water (control), as well as 200 mM and 400 mM NaCl. Biometric parameters such as leaf and radicular biomass, plant height, root length, and biochemical parameters—such as photosynthetic pigments, main ions accumulation, proline, total soluble sugars, malondialdehyde, total phenolics, flavonoids, and antioxidant enzymes’ activity—were quantified. The results showed a certain reduction in leaf and stem plant growth up to 60% in response to extreme salinity, while root biomass was maintained under mid-salt stress. Salt stress caused toxic ions to accumulate in plant organs, up to 1600 mmol g⁻¹ dry weight Na⁺ and a 2250 mmol g⁻¹ dry weight Cl⁻ in leaves under extreme salinity exposure. However, S. dasyphyllum maintained K⁺ levels at around 450 mmol g⁻¹ in leaves and roots and 750 mmol g⁻¹ in stems, indicating a mechanism related to ion transport to cope with ion toxicity. The biochemical response indicated osmotic adjustments and antioxidant activity without the need of activating antioxidant enzymes. S. dasyphyllum has proved to be a valuable genetic tool for new eggplant breeding programs regarding salt stress, with somewhat improved performance regarding biometric parameters and ion transport. Full article

Plant growth, nutrient uptake and fruit quality may be influenced by fertilization practices. A 64-day greenhouse pot experiment, with a 6X1 factorial, i.e., Solanum melongena L. (cv. ‘Lagkadas’) plants, grown on soil substrate and submitted to six fertilization treatments (Patent Kali, Ammonium Nitrate + Patent Kali, Tree Branch Chips, Poultry Manure, Tree Branch Chips + Poultry Manure, and non-fertilization—CONTROL) was conducted. The objectives were to investigate the impact of fertilization on: (i) plant growth, (ii) nutrition, (iii) photosystem II activity and (iv) fruit quality. The main results were the following: a) the highest total plant and fruit biomass values were recorded in poultry manure, followed by those in the ammonium nitrate + patent kali treatment; (b) in most cases, total plant macronutrient content was significantly higher in the poultry manure-treated plants; (c) the optimum and most balanced plant nutrition, fruit total phenolic and flavonoid contents and antioxidant activity levels were achieved in the poultry manure, tree branch chips + poultry manure and ammonium nitrate + patent kali treatments; (d) significant decline in the values of the maximum quantum yield of photosystem II, performance index and fruit quality was found in the tree branch chips and CONTROL plants. It was concluded that the kind of fertilization significantly influenced biomass, nutrient uptake, chlorophyll content and fluorescence, as well as fruit quality of Solanum melongena L. plants. Thus, it should be thoroughly investigated, towards substituting high fertilization rates by manure applications and improving fruit quality, with human health benefits. Full article

This is a pioneering study on the main drainage system in Gujranwala District, where untreated mixed wastewater is discharged and subsequently used for vegetable irrigation, leading to potential health and environmental risks. This study seeks to develop the spatial pattern of toxic metal accumulation in soil across an 11 km stretch of land used for vegetable cultivation. By using 90 samples of mixed wastewater and sludge, as well as 10 quadruplicate samples of rhizospheric soils and crops from ten vegetable fields, it was observed that the concentrations of Cr, Cu, Cd, Zn, Fe, Pb, Mg, and Ni in cauliflower (Brassica oleracea var. botrytis L.), coriander (Coriandrum sativum L.), radish (Raphanus sativus L.), mustard (Brassica juncea L.), spinach (Spinacia oleracea L.), meadow clover (Trifolium sp. L.), sorghum (Sorghum bicolour L.), garlic (Allium sativum L.), brinjal (Solanum melongena L.), and mint (Mentha L.) were beyond the permissible limits set by the FAO/WHO, 2001. The declining trend of the toxic metal concentrations in the effluent was Mg > Cr > Ni > Zn > Pb > Cd > Cu > Fe, and in sludge, soil, and plants, it varied in the order of Mg > Fe > Cr > Ni > Zn > Pb > Cd > Cu. Radish, mint, and brinjal had the highest quantities of toxic metals. The spatial pattern of toxic metals was determined by using proximity interpolation, Inverse Distance Weighted (IDW), the fine tuning of the interpolation characteristics, and the kriging of selected sample variograms. Toxic metals were found in the following order: plants > soil > sludge > effluents. The most prevalent cause of metal pollution was soil irrigation with polluted water. This study provides crucial information about the extent of contamination, which could help in the identification of public health risk, the assessment of environmental impacts, and also sustainable water management. Full article

Environmental sustainability is a crucial issue in modern agriculture and special attention needs to be paid to soil health preservation. Eggplant (Solanum melongena L.) cultivation implies the supply of relevant quantities of chemical fertilizers, since the crop has high nutrient requirements. This study investigated the combined effects of two common organic amendments—compost and digestate—and two types of biostimulant—a plant-based product and a microbe-based product—on fruit production and quality of eggplant, to highlight the potential synergistic effects of fertilization and biostimulation. The experiment was carried out in a Mediterranean greenhouse in the winter/spring period, assessing early and total marketable yield and fruit qualitative traits (firmness, color, nitrogen, ascorbic acid, carotenoid and phenol content, and antioxidant activity). Results showed that the fertilization strategy significantly influenced plant productivity, with digestate promoting the early fruitification and mineral fertilizers resulting in a higher total yield. Biostimulants, particularly the microbial type, improved the fruit quality in terms of carotenoid content and antioxidant activity. These findings highlight the potential benefits of combining organic amendments with biostimulants in eggplant cultivation, enhancing the economic value of the product through the increase in the early production and fruit nutraceutical value while realizing sustainable practices. Full article

Light quality is a fundamental factor in greenhouses, since different light wavelengths affect plant photosynthesis and photomorphogenesis differently, they thus affect crop growth and productivity. The aim of this study was to evaluate the effect of an experimental greenhouse cover film with UV-to-Red spectral shifting properties on photosynthesis, plant growth, fruit yield, and the quality of two crops spanning over a year-long cultural cycle: aubergines (Solanum melongena L.), as a spring–summer crop, followed by strawberries (Fragaria × ananassa Duch.), as an autumn–spring crop. Trials were carried out in a multispan greenhouse where two sectors were covered, each one with a different light diffusing polyethylene film: one sector was covered with a UV-to-Red photoluminescent film, doped with a blend of rare-earth elements partially converting the UV solar radiation into Red wavelengths, while a light diffusing polyethylene film was used as the control. At the physiological level, spectral shifting affected the chlorophyll fluorescence parameters related to the photochemistry of photosynthesis, which were found to be positively related to crop yield. Moreover, differential analysis of the fast Chlorophyll a fluorescence transients (or OJIP kinetics) showed that spectral shifting affected different steps of the plant photochemical metabolism. Full article

The homeodomain–leucine zipper (HD-zip) gene family plays a crucial role in plant development and stress responses. However, systematic identification studies of this gene family in eggplant are still lacking. In this study, we systematically identified 44 HD-zip genes in the eggplant genome database using bioinformatics methods and analyzed their expression levels under light and multiple hormones by RT-qPCR. The results show that members of the SmHD-zip gene family were classified into four groups (HD-zip I, II, III, and IV) based on the phylogenetic relationship. Cis-acting elements related to plant development, hormones, and stress were identified in the promoter regions of the SmHD-zip gene family. Furthermore, the expression of the SmHDZ2 gene was upregulated during the fruit development stage, while nine SmHD-zip genes exhibited downregulated expression patterns. Notably, some SmHD-zip genes were identified as key regulators of eggplant responses to light and multiple hormone signals. Overall, these findings not only provide valuable insights into the evolutionary and functional characteristics of eggplant HD-Zips but also suggest that HD-zip genes likely play a significant role in regulating fruit development and ripening by integrating light and multiple hormone signaling pathways. Therefore, this study laid the foundation for further research on eggplant quality. Full article

Background/Objectives: The skin, being the body’s outermost organ, plays a vital role in protecting against various external stimuli. Ultraviolet generates reactive oxygen species (ROS), promoting the secretion of matrix metalloproteinases (MMPs) and inducing collagen degradation. Many studies have been conducted to identify natural substances that can prevent or delay the harmful effects of UV. Methods: A wound healing assay, DCF-DA reactive oxygen species (ROS) assay, and JC-1 assay were performed to assess the effects of bio-converted eggplant peels (BEPs) on human dermal fibroblasts (HDFs). Western blot analysis was also conducted to understand the underlying mechanisms for their effects. Finally, hematoxylin–eosin staining and immunohistochemistry were also performed in animal studies. Results: Our study evaluated the antioxidant efficacy of BEPs fermented with Lactobacillus plantarum in hydrogen peroxide (H₂O₂)-HDFs and UVB-induced skin damage in hairless mice. We demonstrated that BEPs exhibited enhanced antioxidant properties compared to non-fermented eggplant peels (EPs). BEPs facilitated wound healing in H₂O₂-damaged HDFs, reduced ROS levels, and restored mitochondrial membrane potential. BEPs suppressed the phosphorylation of ERK, p38, and JNK as their underlying mechanism. We further demonstrated that dietary supplementation of BEPs also downregulated matrix metalloproteinase 1 (MMP1) expression and upregulated collagen I (COL1) in UVB-damaged hairless mice, indicating that BEPs were more effective compared to EPs. Conclusions: Our studies suggest that BEPs fermented with Lactobacillus plantarum hold significant potential as a protective agent for mitigating UVB-induced damage and promoting skin health. Full article

Low temperature, weak light, and the combination of low temperature and weak light can have an impact on the growth, development, and quality of eggplants. The color of the eggplant peel is affected by the anthocyanin content. To better understand the influence of low temperature, weak light, and the combination of low temperature and weak light on the regulation of anthocyanins in the eggplant peel, four treatments were carried out on the eggplants, respectively: low temperature (18/13 °C, 250 μmol/(m²·s)), weak light intensity (WL, 25/20 °C, 120 μmol/(m²·s)), low temperature combined with weak light intensity (LW, 18/13 °C, 120 μmol/(m²·s)), and the control (CK, 25/20 °C, 250 μmol/(m²·s)). The effects of low temperature and weak light on the anthocyanin content in various parts of the eggplant were analyzed, and transcriptome analysis was performed on the eggplant peel under the treatments of low temperature, weak light, and the combination of low temperature and weak light using RNA sequencing. The anthocyanin content in eggplants increased under low temperature and the combination of low temperature and weak light treatments, while it decreased under weak light. KEGG analysis showed that three pathways, namely phenylpropanoid biosynthesis, flavonoid biosynthesis, and anthocyanin biosynthesis, were involved in the anthocyanin biosynthesis of eggplants. Pearson correlation coefficients indicated that the anthocyanin content in the eggplant peel under low temperature and the combination of low-temperature and weak-light treatments was significantly correlated with SmPAL, Sm4CL, SmCYP73A100, SmCHS, SmCHI, F3H, DFR, ANS, and 3GT, and also significantly correlated with MYB, bHLH, and AP2/ERF. Under low-temperature and the combination of low-temperature and weak-light stress, the anthocyanin content increased due to the significant down-regulation of 3GT. Full article

Peel glossiness is an important commercial trait of eggplant (Solanum melongena L.). In this study, two eggplant-inbred lines with different levels of peel glossiness were used to identify genes related to peel glossiness. Paraffin section analysis showed that increased wax thickness and wrinkles on the wax surface of eggplant peels decreased glossiness. Differential gene expression related to eggplant peel glossiness was analyzed by comparing the transcriptomes of eggplant peels with different gloss levels and at different developmental stages. The results identified 996 differentially expressed genes (DEGs), including 502 upregulated and 494 downregulated genes, possibly related to eggplant peel glossiness. GO enrichment and KEGG enrichment analyses revealed that the DNA replication pathway (GO:0003688, GO:0006270) and the photosynthesis pathway (map00195) were downregulated and thus may be associated with reduced eggplant peel glossiness. Expression level analysis of eggplant peels with different glossiness levels revealed that a C2H2 transcription factor gene, two ERF transcription factor genes, one long-chain acyl-CoA synthetase gene, and four wax- or cutin-related genes may be associated with the glossiness of eggplant fruit peels. These findings will help guide future genetic improvements in eggplant peel glossiness. Full article

Eggplant (Solanum melongena L.) is a widely cultivated vegetable belonging to the family Solanaceae. However, it is highly susceptible to yield reduction owing to soil-borne diseases caused by bacterial wilt (BW) (Ralstonia solanacearum L.). Therefore, understanding the mechanism of bacterial wilt resistance in eggplant is helpful for genetic improvement to create cultivars with strong bacterial wilt resistance. In this study, we conducted a comparative analysis of transcriptomics from eggplant varieties of different genotypes following infection with R. solanacearum. Transcriptome analysis revealed the majority of differentially expressed genes (DEGs) primarily implicated in pathways such as the MAPK signaling pathway, plant hormone signal transduction, and plant–pathogen interactions, as determined using Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The expression profiles of hormone pathway genes suggest that salicylic acid, ethylene, and jasmonic acid may play significant roles in conferring bacterial wilt resistance. DEGs from the leaves, roots, and stems were partitioned into 14 modules. Among these, the black module exhibited the strongest correlation with target traits and 16 hub genes were identified using gene co-expression network analysis. Subsequently, seven hub genes were selected for validation using RT-qPCR, and the results were consistent with the RNA-seq data. Notably, upon gene annotation, a significant proportion of the hub genes were annotated as heat shock proteins (HSPs) or heat shock transcription factors (HSFs). These findings offer valuable insights for advancing research on the molecular genetic mechanisms through which HSPs/HSFs contribute to bacterial wilt resistance in eggplant. Full article

This study examines the potential of natural biostimulants to mitigate environmental stress and enhance growth, yield, and quality in eggplant (Solanum melongena L., cv. Black Beauty) grown in loamy sand soil. Eggplants were treated with foliar applications of ascorbic acid (AA) at 300 mg/L, chitosan (Ch) at 200 mg/L, and moringa oil (MO) at 1000 mg/L as natural biostimulants. Results indicated significant increases in plant height, branch number, leaf chlorophyll content, fruit count, and total yield per feddan (0.42 ha) with the AA, Ch, and MO treatments compared to untreated controls. Treated plants also displayed enhanced fruit characteristics, including increased weight, diameter, length, and size. Biochemical analyses revealed elevated levels of fruit dry matter, ascorbic acid content, total phenols, flavonoids, and antioxidant activity. Untreated plants, in contrast, showed significantly lower values across all measured parameters, indicating higher susceptibility to environmental stressors and reduced growth and fruit quality. These findings underscore the effectiveness of AA, Ch, and MO as biostimulants in enhancing eggplant growth, yield, and fruit quality under loamy sand conditions. Furthermore, the use of biostimulants could be extended to other crops, offering a sustainable approach to improving food security and sustainability in agricultural practices. Full article

Eggplant is a vegetable grown worldwide, and due to quality standards, large amounts of biomass are generated after harvest. Biomass is considered a source of bioactive compounds with antioxidant properties. Therefore, this research aimed to evaluate the bioaccessibility (BA) and antioxidant capacity of microencapsulated alkaloids from eggplant fruit biomass. Eggplant biomass was collected, and the total alkaloid content, antioxidant capacity (TEAC, FRAP, and ORAC), and alkaloid profile (UPLC/MS) were determined before and after the in vitro digestion of encapsulated and non-encapsulated alkaloids. In vitro digestion significantly reduced the total alkaloid content and antioxidant capacity of alkaloid-rich extracts. Microencapsulation increased the bioaccessibility of alkaloid-rich extracts threefold, and the antioxidant capacity increased by up to 50%. The antioxidant capacity of digested microcapsules increased, and their bioaccessibility was higher than that of non-encapsulated alkaloids. Solamargine and solasonine decreased by 17 and 15% BA, respectively, during in vitro digestion; however, microencapsulation protected these alkaloids during in vitro digestion and enhanced their content. This study demonstrates that microencapsulation is a feasible option to protect alkaloids and preserve their antioxidant capacity during gastrointestinal digestion, as well as to give added value to eggplant plant biomass. Full article

This study investigated the effects of grafting on eggplant growth, yield, and disease resistance, with a focus on microbial dynamics in the rhizosphere. Eggplant scions were grafted onto rootstocks of wild eggplant and tomato, with self-rooted eggplants serving as controls. Greenhouse experiments were conducted over an eight-month growing period, using standard field practices such as film mulching and integrated water–fertilizer management. High-throughput sequencing was used to analyze the biological properties and microbial community of the rhizosphere soil. Results showed that plants grafted onto ‘Huimei Zhenba’ and ‘Torvum’ rootstocks yielded up to 36.89% more than self-rooted controls, achieving yields of 4619.59 kg and 4399.73 kg per 667 m², respectively. The disease incidence of bacterial wilt was reduced to as low as 3.33% in the ‘Huimei Zhenba’ treatment, compared to 55.56% in non-grafted controls. Additionally, grafted plants exhibited increased stem diameter and chlorophyll content, with the TL/HM combination reaching 54.23 ± 3.17 SPAD units. The enhanced microbial biomass of carbon, nitrogen, and phosphorus, particularly in the TL/HM treatment (377.59 mg/kg, 28.31 mg/kg, and 36.30 mg/kg, respectively), supports a more nutrient-rich rhizosphere environment. Moreover, soil enzyme activities, such as β-glucosidase and phosphatase, were significantly higher in grafted plants, enhancing nutrient cycling and potentially increasing resistance to pathogens. Overall, grafted eggplants demonstrated enhanced soil microbial biomass, enzyme activity, and a more diverse microbial community, which are critical factors contributing to the improved yield and disease resistance observed in grafted crops. Full article