Search Results (81)

Background: There is a high demand for long-term postharvest storage of valuable perishables with high-quality preservation and minimal product loss due to decay and physiological disorders. Postharvest low-pressure storage (LPS) provides a viable option for many fruits. While recent studies have presented the details of technology, this pilot study presents the metabolomics changes due to the hypobaric storage of pomegranates as a model system. Methods: Nuclear magnetic resonance (NMR)-based metabolomics studies were performed on pomegranate fruit tissues, comparing fruit stored under LPS conditions versus the traditional storage system, with modified atmosphere packaging (MAP) as the control. The metabolomic changes in the exocarp, mesocarp, and arils were measured using ¹H NMR spectroscopy, and the results were analyzed using multivariate statistics. Results: Distinguishable differences were noted between the MAP and LPS conditions in fruit quality attributes and metabolite profiles. Sucrose levels in the aril, mesocarp, and exocarp samples were higher under LPS, while sucrose levels were reduced in MAP. In addition, alanine levels were more abundant in the mesocarp and exocarp samples, and ethanol concentration decreased in the exocarp samples, albeit less significantly. Conclusions: This pilot investigation shows the potential for using NMR as a valuable assessment tool for monitoring the performance of viable long-term storage conditions in horticultural commodities. Full article

In this study, the association between Neosilba batesi (Diptera: Lonchaeidae) and avocado fruits (Persea americana L.) was investigated. Fruits showing signs of rot and infested with Diptera larvae were collected from commercial orchards in the states of Michoacán and Jalisco, Mexico. N. batesi was identified in association with fruits from both trees and the ground at all sampling sites. Furthermore, a phylogenetic analysis based on the mitochondrial cytochrome c oxidase subunit I (COI) gene supported the morphological identification, showing >99% identity with records from Veracruz, and revealed distinct genetic lineages within the Neosilba genus. In a study within one Michoacán orchard, infested tree-borne fruits averaged 5.40 cm in length and 3.90 cm in width, with a mean of 9.61 larvae emerging per fruit. Females were observed to lay eggs in openings between the pedicel and the fruit, never piercing the exocarp. In contrast, on fallen fruit, they utilized existing wounds with exposed pulp. Infested avocados exhibit characteristic spots indicating the presence of internal larvae and generally detach from the tree. Larvae can feed on avocados in various stages of decomposition and may either emerge through wounds or pupate within the fruit. These findings support the opportunistic and saprophagous behavior associated with this fly species. Full article

Background: β-ketolipoyl coenzyme A synthase (KCS) is an essential limiting catalyst involved in carbon chain elongation during fatty acid biosynthesis, characterized by strict substrate specificity. C18:1 (oleic acid) plays a vital role in cell membranes and is essential for nutrient storage and stress defense. There are indications of significant accumulation and rapid synthesis of C18:1 during the early growth stages of Ginkgo biloba L. episperm. The KCS gene family in G. biloba has yet to be analyzed, and the role of KCS in oleic acid synthesis remains unexplored. Methods: In this study, this issue was investigated using transcriptomic and metabolomic data, bioinformatics analysis to screen a key gene from the KCS gene family, and dual validation using yeast and Arabidopsis thaliana expression systems to probe its function. Results: A total of 11 members of the GbKCS gene family were identified, and the dynamics of these genes were analyzed during exocarp development in the G. biloba genome. Among them, the gene designated GbKCS7 showed a highly direct association with the content of C18:1. Heterologous expression of GbKCS7 in yeast increased C18:1N12 and C18:1 content by 3.18-fold and 2.07-fold, respectively. Overexpression of GbKCS7 in Arabidopsis showed that C18:1 was increased by 27.70% and 31.43% in GbKCS7-OE-1 and GbKCS7-OE-2 strains, correspondingly, in juxtaposition to the non-transgenic plants. In addition, the content of VLCFAs increased to varying degrees. Conclusions: These outcomes offer important insights for investigating the role of KCS genes in fatty acid synthesis to further improve G.biloba resistance. Full article

Geographical origins and varietal characteristics can significantly affect the quality of Citri Reticulatae Pericarpium (Chenpi), making rapid and accurate identification essential for consumer protection. To overcome the inefficiency and high cost of conventional detection methods, this study proposed a nondestructive approach that integrates hyperspectral imaging (HSI) with deep learning to classify Chenpi varieties and their geographical origins. Hyperspectral data were collected from 15 Chenpi varieties (citrus peel) across 13 major production regions in China using three dataset configurations: exocarp-facing-upward (Z), endocarp-facing-upward (F), and a fused dataset combining random orientations (ZF). Convolutional neural networks (CNNs) were developed and compared with conventional machine learning models, including partial least-squares discriminant analysis (PLS-DA), support vector machines (SVMs), and a multilayer perceptron (MLP). The CNN model achieved 96.39% accuracy for varietal classification with the ZF dataset, while the Z-PLSDA model optimized with second derivative (D2) preprocessing and competitive adaptive reweighted sampling (CARS) feature selection attained 91.67% accuracy in geographical origin discrimination. Feature wavelength selection strategies, such as CARS, simplified the model complexity while maintaining a classification performance comparable to that of the full-spectrum models. These findings demonstrated that HSI combined with deep learning could provide a rapid, nondestructive, and cost-effective solution for Chenpi quality assessment and origin traceability. Full article

Squid is rich in polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which exert various human health benefits. Pan-fried squid is a popular processed product beloved by consumers. However, the PUFAs of squid can be severely oxidized during thermal processing, which will result in the reduction in nutritional value and generation of harmful compounds like aldehydes. In this study, flavonoids extracted from coconut exocarp (CEF) and the metal ion chelating agent disodium ethylenediaminetetraacetate (EDTA-2Na) were used to inhibit lipid oxidation during the frying of squid, with the lipid oxidation level, the changes in fatty acid composition, and aldehyde concentrations being examined by gas chromatography mass spectrometry and high-performance liquid chromatography mass spectrometry. Results indicated that during pan-frying, the peroxide value, thiobarbituric acid value, and total oxidation value increased significantly, while the contents of EPA and DHA decreased significantly, and the concentrations of most aldehydes increased in a time- and temperature-dependent pattern. Both CEF and EDTA-2Na treatments inhibited these changes; comparatively, the CEF treatment was significantly better than that of EDTA-2Na. For instance, the CEF treatment inhibited the generation of HHE by 31.90%, 33.24%, and 19.73%, respectively, after pan-frying of squid at 180 °C for 6, 8, and 10 min, while the corresponding values for HNE were 22.65%, 18.96%, and 17.28% respectively. These results suggested that CEF can improve the oxidative stability of squid lipids during pan-frying and reduce the generation and accumulation of aldehydes and improve the security of processed squid products. Full article

Background: The PDX2 gene serves as a critical catalytic component in vitamin B6 (VB6) biosynthesis pathways and plays pivotal regulatory roles in plant growth. Methods: To investigate the metabolic regulation of PDX2 (GbPDX2) from Ginkgo biloba in VB6 biosynthesis during kernel development, we successfully cloned this gene and conducted systematic expression profiling through qRT-PCR across multiple tissues and developmental stages. Results: Bioinformatic characterization revealed that GbPDX2 contains a 765-bp coding sequence encoding a 254-amino acid polypeptide. The encoded protein displays typical hydrophilic properties (average hydrophobicity index: −0.32) and was predicted to be an unstable cytosolic protein (instability index: 45.7) lacking signal peptides or transmembrane domains with cytoplasmic localization. Phylogenetic analysis demonstrated that GbPDX2’s closest evolutionary relationship was with its ortholog in Picea sitchensis, which had an amino acid sequence similarity of 83.7% with spruce PsPDX2. Tissue-specific expression analysis revealed a gradient expression profile of Kernel > Exocarp > Leaves > Stems > Roots. The expression level in kernels was significantly higher than that in other tissues (19.7 times that in roots, 8.3 times that in stems, and 5.9 times that in leaves; p < 0.01), with peak transcript levels observed in mature kernels. HPLC quantification established a strong positive correlation between GbPDX2 expression dynamics and VB6 accumulation patterns during kernel maturation (r = 0.92, p < 0.01), and the peak period of VB6 reached 288.9 ± 7.1 μg/g. Conclusions: Our findings provide the first experimental evidence that GbPDX2 spatiotemporally regulates VB6 biosynthesis in ginkgo kernels, offering novel insights into the evolutionary adaptation of vitamin metabolism in gymnosperms. Full article

This study aimed to characterize carotenoid profiles and unravel the genetic mechanisms underlying flesh color variation in white and yellow-fleshed peaches, with a focus on the hybrid cultivar ‘ZY29’ derived from two white-fleshed parents (‘Yulu’ and ‘Hujing Honey Dew’). Using UPLC-APCI-MS/MS, we quantified carotenoids in the pericarp (exocarp) and flesh (mesocarp) of parental and hybrid fruits. Results showed that ‘ZY29’ accumulated significantly higher levels of β-carotene and lutein compared to its white-fleshed parents. Transcriptome analysis revealed upregulation of carotenoid biosynthesis genes (PSY, LCYB, and ZDS) and downregulation of the carotenoid cleavage gene CCD4 in ‘ZY29’, explaining enhanced carotenoid accumulation. Integrative metabolome-transcriptome analysis identified core regulatory networks associated with metabolic shifts, including transcription factors (MYB and WRKY). These findings provide novel insights into the molecular basis of yellow flesh formation in peaches, offering potential targets (PSY and LCYB) and metabolic markers (β-carotene and lutein) for breeding nutritionally enriched cultivars. These findings contribute to a better understanding of the genetic factors and parental regulatory mechanisms involved in the formation of yellow flesh color in peaches. Our results have important implications for breeding new peach varieties with desirable color and nutritional qualities and may provide valuable insights for future research in this area. Full article

Corozo (Bactris guineensis H.E. Moore) is a fruit from the Colombian Caribbean region valued for its thermostable anthocyanins, which are responsible for its characteristic reddish colour. This study aimed to evaluate the physicochemical, structural, and functional properties for an intelligent and biodegradable film design based on a polyvinyl alcohol (PVOH) matrix incorporating a Corozo extract rich in anthocyanins, with potential applications in food packaging. Anthocyanins were extracted from Corozo fruit and evaluated throughout a central composite design (CCD) for the effects of three variables—extraction time (t), temperature (T), and solvent concentration (CS). A quadratic model (R² = 0.9586) demonstrated that the exocarp (peel) was the most effective source of anthocyanins. The best conditions were a 1:16.66 solid-to-solvent ratio at 50 °C for 75 min, yielding 38.65 mg EC₃G/L. PVOH films were formulated using Corozo anthocyanin extract (CAE), which was characterised for the total anthocyanin content. Characterisation of the films revealed that the incorporation of Corozo-derived phenolic compounds did not cause significant (p < 0.05) changes in structural or water interaction properties compared to those of the control sample. Full article

The marketability of fresh granadilla (Passiflora edulis) fruit is significantly reduced by oxidation reactions occurring in its exocarp, which is not directly linked to the organoleptic quality of its arils. However, organic means of mitigating this are not topical in research. This study investigated the potency of moringa (Moringa oleifera)-based coating to preserve antioxidant compounds in granadilla. Physiologically mature fruit of equal size were assigned to a completely randomized design experiment at the North-West University Farm Laboratory. The fruit samples were coated with 2% xanthan gum (commercial coating), 2% moringa, or 2% rosemary coating and kept at shelf-life conditions (25 ± 2 °C; 40 ± 5%RH) for 5 weeks while sampling at weekly intervals. Correlations between the measured parameters were confirmed prior to regression analysis. Significant (p < 0.05) differences were observed in weekly changes in the exocarp pH, total antioxidant compounds (TAO), tartaric acid (TA), malic acid (MA), and citric acid (CA). At the end of storage, the moringa- and xanthan-coated fruit had the highest exocarp pH (7.8) and TAO (0.87 mg/g). Moringa-coated fruit had higher TA and MA (6.0 and 5.36 µg/g, respectively) as well as a significantly higher CA (0.51 µg/g) preserved than the other coatings. Strong correlations between MA and TAO (r > 0.82), as well as TA and TAO (r > 0.86), indicated the potency of developing TAO estimation models using multivariate data from the organic acids. Pre-processed data regression models were developed but were limited by the amount of data collected. Models developed similarly can be used for sustainable TAO assessment as a latent variable to minimize toxic waste that results from wet chemistry analyses. Full article

Gene duplication, as a prevalent phenomenon in the tree of life, provides a potential substrate for evolution. However, its role in the Aurantioideae remains unclear. In this study, we systematically identified, for the first time, a comprehensive landscape of five types of gene duplication in the genomes of 26 species within Aurantioideae, focusing on dissecting the duplication patterns, their potential evolutionary significance, and their impact on gene function and expression. Our results showed that the tandem duplication (TD) was a predominant duplication type and confirmed a shared ancient whole-genome duplication (γWGD) event within Aurantioideae. Ka/Ks indicated that all duplication types are under purifying selection pressure, with TD and proximal duplication (PD) undergoing rapid functional divergence. Gene Ontology (GO) enrichment analysis revealed functional specialization among different duplication types, collectively contributing to genome evolution. In addition, comparing the gene expression differentiation of the five gene duplication types between the outer and inner pericarps of Citrus maxima ‘Huazhouyou’, it was found that the proportion of gene expression differentiation in the exocarp was generally higher, suggesting tissue-specific functional roles for duplicated genes in the peel. Furthermore, gene conversion events revealed that Citrus sinensis and Citrus maxima ‘Huazhouyou’ experienced more gene conversion events, supporting that C. sinensis originated through hybridization with C. maxima as the maternal parent. Finally, the comparative analysis of gene families among 26 species in Aurantioideae revealed that small gene families (1–3 members) accounted for a substantial proportion in all species, indicating a lack of recent large-scale genome duplication events in this subfamily. These findings fill a gap in the understanding of gene duplication in Aurantioideae and provide a theoretical foundation for exploring the evolutionary mechanisms and breeding improvements within this group. Additionally, our study offers new insights into the contribution of gene duplication to functional diversification and ecological adaptation in other plants. Full article

Fluorescence imaging has emerged as a powerful tool for detecting surface damage in fruits, yet its application to vegetables such as green bell peppers remains underexplored. This study investigates the fluorescent characteristics of minor mechanical damage, specifically 5 × 5 mm cuts in the exocarp of green bell peppers, which conventional digital imaging techniques fail to classify accurately. Chlorophyll fluorescence imaging was combined with machine learning algorithms—including logistic regression (LR), artificial neural networks (ANN), random forests (RF), k-nearest neighbors (kNN), and the support vector machine (SVM) to classify damaged and sound fruit. The machine learning models demonstrated a high classification accuracy, with calibration and prediction accuracies exceeding 0.86 and 0.96, respectively, across all algorithms. These results underscore the potential of fluorescence imaging as a non-invasive, rapid, and cheaper method for assessing mechanical damage in green bell peppers, offering valuable applications in quality control and postharvest management. Full article

Using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) technology in multiple reaction monitoring mode, a widely targeted metabolomics approach was employed to identify metabolites in five tissues (exocarp, endocarp, segment membrane, pulp, and seeds) of the Shatian pomelo fruit. The differences in metabolite composition and abundance among different tissues were analyzed using multivariate statistical analysis methods. The results showed that a total of 1722 metabolites were identified from the five tissues of the Shatian pomelo, including 413 flavonoids and 277 amino acids and their derivatives. Flavonoid metabolites accumulate the most abundantly in the exocarp and seeds, while amino acids and their derivatives are primarily accumulated in the exocarp and pulp. A total of 649 key differential metabolites were screened, including flavonoids, amino acids, and their derivatives, indicating the presence of tissue-specific accumulation of metabolites in the Shatian pomelo. This study systematically investigated the metabolite distribution in different tissue parts of the Shatian pomelo, and validated the feasibility of widely targeted metabolomics technology in pomelo quality analysis. It provided a theoretical reference for metabolic research on the Shatian pomelo and other citrus fruits, and offered a theoretical basis for the efficient utilization of pomelo resources. Full article

PIWI, from the German word Pilzwiderstandsfähig, meaning “fungus-resistant”, refers to grapevine cultivars bred for resistance to fungal pathogens such as Erysiphe necator (the causal agent of powdery mildew) and Plasmopara viticola (the causal agent of downy mildew), two major diseases in viticulture. These varieties are typically developed through traditional breeding, often crossbreeding European Vitis vinifera with American or Asian species that carry natural disease resistance. This study investigates the transcriptional profiles of exocarp tissues in mature berries from four PIWI grapevine varieties compared to their elite parental counterparts using RNA-seq analysis. We performed RNA-seq on four PIWI varieties (two red and two white) and their noble parents to identify differential gene expression patterns. Comprehensive analyses, including Differential Gene Expression (DEGs), Gene Set Enrichment Analysis (GSEA), Weighted Gene Co-expression Network Analysis (WGCNA), and tau analysis, revealed distinct gene clusters and individual genes characterizing the transcriptional landscape of PIWI varieties. Differentially expressed genes indicated significant changes in pathways related to organic acid metabolism and membrane transport, potentially contributing to enhanced resilience. WGCNA and k-means clustering highlighted co-expression modules linked to PIWI genotypes and their unique tolerance profiles. Tau analysis identified genes uniquely expressed in specific genotypes, with several already known for their defense roles. These findings offer insights into the molecular mechanisms underlying grapevine resistance and suggest promising avenues for breeding strategies to enhance disease resistance and overall grape quality in viticulture. Full article

The pequi (Caryocar brasiliense) fruit peel, despite being frequently discarded, has a high content of bioactive compounds, and therefore has a high nutritional value. The present study aimed to explore the bioactivities in the pequi peel, particularly their potential health benefits at the level of antioxidant activity. The exploitation of this fruit could also present significant economic benefits and applications of pequi by-products would represent a reduction in waste, having a positive impact on the environment. Phenolic compounds present in the pequi exocarp and external mesocarp were identified by paper spray mass spectrometry (PS-MS) and quantified by HPLC. The total phenolic content (TPC) along with the amount of 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), and the amount of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) were also determined in peel extracts. Epicatechin was the most abundant phenolic compound found, followed by the caffeic, salicylic, and gallic acids. In addition, fingerprinting revealed compounds related to several beneficial health effects. In short, the results obtained were encouraging for potential applications of pequi peel in the field of functional foods. Full article

The maturation of Arabica coffee fruits is influenced by both endogenous and external factors. The stage of fruit maturation affects the chemical composition of the beans, which in turn impacts the quality of the coffee beverage. During maturation, the fruit peel changes colour from green to red (cherry), signalling the optimal harvest time and suggesting high fruit quality. However, the degree of redness can vary, indicating different levels of maturity. This study aimed to explore the variation in soluble sugar accumulation in relation to the redness of coffee fruit tissues. We classified ripe fruits into six ripeness categories based on the intensity of the red colour of the epicarp, measured using a colourimeter. We analysed total soluble sugar, sucrose, and starch in three parts: coat (exocarp + mesocarp), coat juice (obtained by squeezing the coat), and beans. Our findings reveal that the variation in sugar in the endosperm does not correspond to changes in the coat, suggesting separate regulation of sugar accumulation, particularly sucrose, which is crucial for coffee quality. Our data indicate that there is no transfer of sucrose and reducing sugars from the red coat to the bean. Full article