Search

Mango fruit undergoes various physiochemical changes after its harvest that affect consumer acceptability. The present research work was carried out to evaluate the preservation effect of sodium nitroprusside (SNP) treatments on the postharvest quality of mango cv. Langra fruits at 12 ± 1°C for 35 days. The results revealed that SNP 1.0 mM treated fruits exhibited reduced weight loss (6.94%), decay incidence (8.05%), and activities of cell wall degrading enzymes like polygalacturonase and pectin methyl esterase in comparison to uncoated fruits on the last day of storage. Furthermore, the treatment maintained higher fruit firmness (56.77 N) along with fruit quality parameters like soluble solid content (16.24%), titratable acidity (0.20%), starch (4.99%), and, total flavonoid content (12.92 mg/100 g). Overall, SNP 1.0 mM combined with low-temperature storage was proved to be the most effective in extending the shelf life and preserving the quality characteristics of mango fruits. [ABSTRACT FROM AUTHOR]

SUMMARY Stylosanthes is an important forage legume in tropical areas with strong resistance to aluminum (Al) toxicity, though knowledge of mechanisms underlying this resistance remains fragmentary. We found that border‐like cells (BLCs) were constitutively produced surrounding the root tips of all 54 examined Stylosanthes guianensis genotypes, but not the Stylosanthes viscose genotype TF0140. In genotypic comparisons under Al conditions, the S. guianensis genotype RY#2 retained significantly more Al in BLCs and thereby showed higher relative root growth than TF0140. Formation of BLCs accompanied changes in cell wall pectin epitopes and differential expression of genes involved in pectin metabolism, including a polygalacturonase (SgPG1). The expression pattern of SgPG1 was consistent with the formation of BLCs in both RY#2 and TF0140. SgPG1 was localized in cell walls and exhibited high activities mediating demethyl‐esterified homogalacturonan degradation. Overexpressing SgPG1 changed cell wall pectin epitopes, enhanced BLCs production, and Al resistance in both Arabidopsis and Stylosanthes hairy roots. Furthermore, combining protein‐DNA binding assays in vitro and in vivo, a bHLH transcription factor SgbHLH19 was demonstrated to be the upstream regulator of SgPG1. Our study demonstrates that S. guianensis Al resistance mainly relies on BLCs, whose formation involves cell wall pectin epitope modification by SgPG1. [ABSTRACT FROM AUTHOR]

Agricultural crop yield losses and food destruction due to infections by phytopathogenic bacteria such as Burkholderia gladioli, which causes devastating diseases in onion, mushroom, corn, and rice crops, pose major threats to worldwide food security and cause enormous damage to the global economy. Biocontrol using bacteriophages has emerged as a promising strategy against a number of phytopathogenic species but has never been attempted against B. gladioli due to a lack of quantitative infection models and a scarcity of phages targeting this specific pathogen. In this study, we present a novel, procedurally straightforward, and highly generalizable fully quantitative ex planta maceration model and an accompanying quantitative metric, the ex planta maceration index (xPMI). In utilizing this model to test the ex planta virulence of a panel of 12 strains of B. gladioli in Allium cepa and Agaricus bisporus, we uncover substantial temperature-, host-, and strain-dependent diversity in the virulence of this fascinating pathogenic species. Crucially, we demonstrate that Burkholderia phages KS12 and AH2, respectively, prevent and reduce infection-associated onion tissue destruction, measured through significant (P < 0.0001) reductions in xPMI, by phytopathogenic strains of B. gladioli, thereby demonstrating the potential of agricultural phage biocontrol targeting this problematic microorganism. IMPORTANCE Agricultural crop destruction is increasing due to infections caused by bacteria such as Burkholderia gladioli, which causes plant tissue diseases in onion, mushroom, corn, and rice crops. These bacteria pose a major threat to worldwide food production, which, in turn, damages the global economy. One potential solution being investigated to prevent bacterial infections of plants is "biocontrol" using bacteriophages (or phages), which are bacterial viruses that readily infect and destroy bacterial cells. In this article, we demonstrate that Burkholderia phages KS12 and AH2 prevent or reduce infection-associated plant tissue destruction caused by strains of B. gladioli, thereby demonstrating the inherent potential of agricultural phage biocontrol. [ABSTRACT FROM AUTHOR]

The polygalacturonase inhibitory protein (CkPGIP1) of Cynanchum komarovii can effectively inhibit the activity of polygalacturonase (VdPG1) of Verticillium dahliae. To further enhance the disease resistance of CkPGIP1, this study started with site-directed mutagenesis of the disease-resistant protein CkPGIP1 to investigate its enhanced inhibitory effect on V. dahliae. Using overlapping extension polymerase chain reaction (PCR) technology, mutant variants T152VCkPGIP1, D202SCkPGIP1, and 1250KCkPGIPI of CkPGIPI were successfully obtained. The corresponding prokaryotic expression vectors were constructed for the induction expression and purification of 923 CkPGIPI and its mutant proteins. The inhibitory effect of the mutant proteins on VdPG1 was determined by 3,5-dinitrosalicylic acid (DNS) method and agarose radial diffusion method. The results of DNS assay showed that the mutant proteins effectively inhibited the activity of VdPG1 in a dose- dependent manner. Among them, the inhibitory effect of D202SCkPGIP1 on VdPG1 was most significant, followed by T152VCkPGIP1, and the inhibitory effect of 1250KCkPGIP1 was not obvious. The results of agarose radial diffusion were consistent with those of DNS assay. D202SCkGIP1-treated V. dahliae showed the most obvious decrease in the halo area of VdPG1, indicating that D202SCkPGIP1 had the most significant inhibitory activity. Further study revealed that the mutant proteins could inhibit the expansion of V. dahliae on cotton leaves, confirming that the key amino acid mutations in CkPGIP1 enhanced its inhibitory effect on V. dahliae. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) dry rot due to fungal infections causes the loss of a significant amount of potatoes. In this study, the antifungal effects of sunflower (Helianthus annuus L.) extracts against Fusarium sulphureum were investigated. The results of in vitro antifungal tests showed that all four sunflower extracts significantly inhibited the growth of F. sulphureum. Notably, the optimal inhibitory concentrations of ethyl acetate extract from sunflower disk (EESD), ethyl acetate extract from sunflower stalk (EESS), petroleum ether extract from sunflower disk (PESD) and petroleum ether extract from sunflower stalk (PESS) against F. sulphureum were 160 mg/mL, 160 mg/mL, 240 mg/mL, and 240 mg/mL, respectively. In addition, these extracts significantly inhibited the activities of polygalacturonase (PG), polymethyl-galacturonase (PMG), carboxymethyl cellulase (Cx), and β-glucosidase (β-Glu) secreted by F. sulphureum in three potato varieties: Longshu No.7, Longshu No.10 and Xindaping. These results provide a theoretical foundation for the biological control of potato dry rot. [ABSTRACT FROM AUTHOR]

In the last decade, the application of non-Saccharomyces yeasts in oenology as a natural tool to obtain wine diversification and higher quality has aroused great interest. In this work, three Metschnikowia pulcherrima strains, isolated from a vineyard, were characterised through the evaluation of their main oenological properties, antimicrobial activity, and specific enzymatic activities (β-glucosidase, β-lyase, polygalacturonase, and protease). The M. pulcherrima strains did not produce any inhibition against Saccharomyces cerevisiae, while they were able to exert an antimicrobial action against some unwanted bacteria and yeasts frequently present in grape must and potentially causing the alteration of wines. After this preliminary screening, M. pulcherrima AS3C1 has been selected to be used in the winemaking of red grape Vitis vinifera cv. Aglianico on a pilot scale. The effect of the sequential inoculation of M. pulcherrima AS3C1 with a commercial strain of S. cerevisiae was verified using for comparison a single inoculum with S. cerevisiae and a spontaneous fermentation. Our results showed a higher concentration of anthocyanins and catechins in wines obtained by the sequential inoculation of M. pulcherrima AS3C1 and S. cerevisiae. On the basis of the data obtained, M. pulcherrima AS3C1 possesses an enzymatic profile and some oenological properties that could contribute positively to the definition of the chemical composition of wines, suggesting its possible use for red winemaking processes. [ABSTRACT FROM AUTHOR]

The main objective of this study was to monitor apricot development and ripening through gene expression analysis of key candidate genes using the RT-qPCR technique. Eight apricot cultivars were selected to analyze phenological and genetic patterns from pre-ripening stages through to postharvest. In addition, 19 selected genes were analyzed in the contrasting cultivars 'Cebas Red' and 'Rojo Pasión' in different stages (two preharvest stages S1 and S2, one harvest stage S3, and two postharvest stages S4 and S5). This pool of genes included genes related to fruit growth and ripening, genes associated with fruit color, and genes linked to the fruit's nutraceutical aspects. Among the studied genes, Polygalacturonase (PG), Pectin methylesterase (PME), Aminocyclopropane-1-carboxylate synthase (ACS), and Myo-inositol-1-phosphate synthase (INO1) were directly related to fruit maturation and quality. Significant differential expression was observed between the cultivars, which correlated with variations in firmness, shelf life, and sensory characteristics of the apricots. 'Rojo Pasión' displayed high levels of PG, associated with rapid maturation and shorter postharvest shelf life, whereas 'Cebas Red' exhibited lower levels of this gene, resulting in greater firmness and extended shelf life. Genes CCD4, CRTZ, and ZDS, related to carotenoids, showed varied expression patterns during growth and postharvest stages, with higher levels in 'Rojo Pasión'. On the other hand, Sucrose synthase (SUSY) and Lipoxygenase (LOX2) were prominent during the postharvest and growth stages, respectively. Additionally, GDP-L-galactose phosphorylase (VTC2_5) was linked to better postharvest performance. This research provides valuable insights for future breeding initiatives aimed at enhancing the quality and sustainability of apricot cultivation. [ABSTRACT FROM AUTHOR]

The ‘Okitsu No. 58’ citrus variety is highly prone to fruit cracking, which jeopardizes yield and results in economic losses. In this study, we investigated the impacts of spraying 5 distinct concentrations (0.1, 0.2, 0.3, 0.4, and 0.5 g/L) of chelated calcium (Ca) or silicon (Si) fertilizers at the young fruit stage (60-90 days after flowering, DAF) on fruit cracking and quality in the citrus variety ‘Okitsu No. 58’. The results showed either Ca or Si fertilizer treatments reduced fruit cracking. We found that all Ca and partial Si treatments (0.4 and 0.5 g/L) significantly promoted the accumulation of Ca content in the peel. Notably, Ca or Si treatments significantly reduced polygalacturonase (PG) activity and inhibited the production of water-soluble pectin (WSP) in the peel. Additionally, Ca or Si treatments elevated the superoxide dismutase (SOD) activity and decreased the malondialdehyde (MDA) content of the peels. Changes in these parameters likely contributed to strengthening the durability of peel cell wall constituents, thus enhancing the fruit’s resistance to fruit cracking. Overall, except for the C3 (0.3 g/L of Ca), Ca or Si fertilizers contributed to fruit conventional quality, mainly in terms of higher soluble sugars (SS) and SS/TA (titratable acid). Therefore, our findings will provide a reference for the prevention and control of citrus fruit cracking and the development of new fertilizers. [ABSTRACT FROM AUTHOR]

In this work, the effects of high-voltage electrostatic field (HVEF) on enzyme activities and appearance of stored Musa sapientum were investigated as well as the intensity of spotting by Digital Image Analysis (DIA). By applying HVEF at 6 kV cm-1 during 7.5 minutes, color features on their surface after day 4, maintained stable values (R ≥ 191, G ≥ 165, L* ≥ 82, and b* ≥ 41), while control samples had lower figures of these parameters. Enzyme activities (expressed as Umg protein-1), for pectinmethylesterase in peel, HVEF treatments induced values ≤ 9 Umg-1, while control ≥ 16 Umg-1; polygalacturonase in peel; HVEF samples had activities ≤ 120 Umg-1 at days 6 and 8, while control samples ≥ 211 Umg-1; and, in pulp, after day 4, HVEF brought activities ≤ 37 Umg-1 while control samples were ≥ 71 Umg-1. Polyphenoloxidase, activities for treated samples were enhanced (in the peel, HVEF samples ≥553 Umg -1 and control ones ≤425 Umg-1; and for pulp, HVEF induced activities ≥979 Umg-1 while control ≤717 Umg -1). These results did not impact negatively in the spotting on the surface of the fruits. Results suggested that HVEF can extend the shelf life of M. sapientum. [ABSTRACT FROM AUTHOR]

Fruit splitting is a prevalent physiological disorder that has a significant impact on Daisy mandarin fruit production, posing challenges to farmers in terms of productivity and economic viability. Despite its impact, no prior research on fruit splitting in Daisy mandarin has been conducted. This study aimed to assess the effect of fruit splitting on quality, morphological characteristics, biochemical composition and nutrient content in Daisy mandarin. In 2022, a comprehensive analysis was conducted on both split and healthy Daisy mandarin fruits, budded on Rough lemon rootstock, to investigate their morphological characteristics, biochemical characteristics, mineral content and cell wall components. Additionally, the study examined the activity of cell wall-degrading enzymes, such as peroxidase (POD), cellulase (Cx) and polygalacturonase (PG). The Results indicated that split fruits exhibited larger fruit size and weight and increased water content in both the fruits and peel compared to healthy fruits. However, split fruits had thinner peel thickness and lower peel content. The peels of split fruits also contained higher level of total soluble sugars, amino acids, and proline content. Furthermore, the peels of split fruits displayed much higher activity of cell wall-degrading enzymes than those of healthy fruits. The nutrient analysis of the split fruits revealed a decrease in boron, calcium and potassium content in the peel compared to healthy fruits. The study provides crucial insights into the mechanisms underlying fruit splitting, identifying biochemical and physiological differences between split and healthy fruits. These findings offer valuable information for developing strategies to mitigate fruit splitting, enhancing fruit quality and reducing economic losses for citrus growers. Future research should explore the genetic and environmental factors contributing to fruit splitting and investigate potential interventions to improve nutrient management and fruit integrity in Daisy mandarin cultivation. [ABSTRACT FROM AUTHOR]

In this work, the application of pectinase enzymes to clarify glucose syrups produced from corn fiber was studied. The enzymatic activity and kinetic parameters of the pectinase enzyme used were quantified. A specific activity of 5,528 U/mg protein, a maximum rate of 19151 U/mL, and a Michaelis-Menten constant of 1,656 mg/mL were obtained. The syrup was prepared by hydrolyzing corn fiber at 50°C and 180 rpm, and a central composite design was performed for the clarification step to find the optimal conditions of enzyme-substrate ratio and agitation. The syrup was heated to a temperature of 50°C, and an enzyme substrate ratio between 2.5 to 4.5 U/mL of syrup and agitation, varying between 215 to 285 rpm, was applied. The conditions to maximize the clarification of corn fiber syrup were determined to be an enzyme substrate ratio of 3.716 U/mL syrup and agitation of 267 rpm. These conditions were validated by taking the syrup from clarity of 65.8% to 88.1%, demonstrating that the methodology used presents advantages in the syrup clarification process. A physicochemical characterization of the corn fiber used to prepare the syrups was carried out, which presented a content of 12.90%, 23.33%, 13.4%, and 0.36% of cellulose, hemicellulose, lignin and pectin, respectively. [ABSTRACT FROM AUTHOR]

Fruit softening is a prominent attribute governing both longevity on shelves and commercial worth. Polygalacturonase (PG) plays a major role in strawberry fruit softening. However, the PG gene family in strawberry has not been comprehensively analyzed. In this study, 75 FaPG genes were identified in the octoploid strawberry genome, which were classified into three groups according to phylogenetic analysis. Subcellular localization prediction indicated that FaPGs are mostly localized to the plasma membrane, cytoplasm, and chloroplasts. Moreover, the expression of FaPGs during strawberry development and ripening of 'Benihoppe' and its softer mutant was estimated. The results showed that among all 75 FaPGs, most genes exhibited low expression across developmental stages, while two group c members (FxaC_21g15770 and FxaC_20g05360) and one group b member, FxaC_19g05040, displayed relatively higher and gradual increases in their expression trends during strawberry ripening and softening. FxaC_21g15770 was selected for subsequent silencing to validate its role in strawberry softening due to the fact that it exhibited the highest and most changed expression level across different developmental stages in 'Benihoppe' and its mutant. Silencing FxaC_21g15770 could significantly improve strawberry fruit firmness without affecting fruit color, soluble solids, cellulose, and hemicellulose. Conversely, silencing FxaC_21g15770 could significantly suppress the expression of other genes related to pectin degradation such as FaPG-like, FaPL, FaPME, FaCX, FaCel, FaGlu, FaXET, and FaEG. These findings provide basic information on the FaPG gene family for further functional research and indicate that FxaC_21g15770 plays a vital role in strawberry fruit softening. [ABSTRACT FROM AUTHOR]

The addition of pectinase enzymes during the maceration stage of grape skins in order to improve the extraction yields and color of red wines is a common practice in many wineries. The objective of this work was to study in depth the changes that occurred in the aminoacidic, volatile, and phenolic compositions of Cabernet Sauvignon wines fermented with a Saccharomyces cerevisiae strain genetically modified with the gene encoding for endopolygalacturonase (PGU1) in transcriptional fusion with the promoter of the phosphoglycerate kinase (PGK1) gene, both from S. cerevisiae origin. A higher yield extraction of wine was obtained in wines fermented with the modified strain (PW), increasing by around 6.1% compared to the control wine (CW). Moreover, there was a 40% decrease in the malic acid content in the PW, thus suggesting that this modified yeast could be investigated as a malic acid-reducing agent. There were slight differences in other aroma volatile compounds studied as well as in the phenolic content. However, there was a considerable increase in the amino acid content in the PW. [ABSTRACT FROM AUTHOR]

This study aimed to isolate a fungal strain capable of producing acidophilic and thermostable polygalacturonase. In this study, the fungal isolate was isolated from decaying tomatoes. Based on the colony characteristics, microscopic and morphological observations, the isolated fungal pathogen has been identified as Aspergillus niger. The isolated fungus was used in solid-state fermentation to produce an acidic polygalacturonase enzyme. The enzyme was then purified using ammonium sulphate precipitation and column chromatography, and its activity was assayed by measuring the releasing sugar group from citrus pectin using a 3, 5-dinitrosalicylic acid (DNSA) reagent assay. The crude extract obtained from solid-state fermentation had an activity of 94.6 U/mL. Ammonium sulphate precipitation increased the enzyme's specific activity from 6.89 U/mg to 12.42 U/mg. Sephadex G-200 was used to purify the enzyme 3.58 times, and its specific activity was determined to be 24.66 U/mg. The Sephacryl S-100 column achieved a final fold purification of 9.93 times and a specific activity of 68.41 U/mg. The purified enzyme performed best when polygalacturonic acid was used as a substrate. The enzyme's optimum temperature and pH were 55°C and 5, respectively. CaCl2 was found to be the best chelating ion for the enzyme. This enzyme is recommended for use in a variety of industrial applications as the enzyme was found to be stable at acidic pH and high temperature. [ABSTRACT FROM AUTHOR]

Mealy peaches are dry and flavorless, which reduces their consumer acceptance. A deeper understanding of the mechanism underlying mealiness is crucial to enhancing peach fruit quality. In this study, comparative profiling was conducted on CP13, CP14, CM, and RM peaches. Sensory evaluation indicated that CP13 and CM are non-mealy clingstone and freestone peaches, respectively, and CP14 and RM are mealy freestone peaches. Both CP13 and CP14, identified as stony hard (SH) peaches, exhibited minimal ethylene release, whereas CM and RM, identified as melting flesh (MF) peaches, released high amounts of ethylene during the ripening process. Scanning electron microscopy (SEM) microstructure observation indicated that cells in the flesh tissue of mealy peaches, CP14 (SH) and RM (MF), were intact and separated, with large intercellular spaces and irregular arrangements. The main factor that promotes mealiness is differences in pectin metabolism, which impact cell wall composition. The fluctuations in polygalacturonase (PG) and pectin methylesterase (PME) activity between mealy and non-mealy peaches were the main factor contributing to mealiness. However, the changes in cell wall metabolism that caused these fluctuations did not have a clear direction. Using transcriptome analysis and weighted gene co-expression network analysis (WGCNA), we were able to identify forty differentially expressed genes (DEGs) that are associated with mealy patterns. Among these DEGs, genes encoding PG were significantly upregulated in mealy peaches (CP14 and RM) compared to non-mealy peaches (CP13 and CM). PpPG1 was the main effector gene for mealiness, while PpPG2, PpEGase2, PpEXP1, PpEXP3, PpAGP2, PpIAA4, and PpABA2 were identified as candidate genes regulating peach mealiness. These findings provide a solid experimental basis for understanding the textual distinctions between mealy and non-mealy peaches. [ABSTRACT FROM AUTHOR]

Abstract Rapeseed (Brassica napus L.), accounts for nearly 16% of vegetable oil, is the world’s second produced oilseed. However, pod shattering has caused significant yield loses in rapeseed production, particularly during mechanical harvesting. The GH28 genes can promote pod shattering by changing the structure of the pod cell wall in Arabidopsis. However, the role of the GH28 gene family in rapeseed was largely unknown. Therefore, a genome-wide comprehensive analysis was conducted to classify the role of GH28 gene family on rapeseed pod shattering. A total of 37 BnaGH28 genes in the rapeseed genome were identified. These BnaGH28s can be divided into five groups (Group A-E), based on phylogenetic and synteny analysis. Protein property, gene structure, conserved motif, cis-acting element, and gene expression profile of BnaGH28 genes in the same group were similar. Specially, the expression level of genes in group A-D was gradually decreased, but increased in group E with the development of silique. Among eleven higher expressed genes in group E, two BnaGH28 genes (BnaA07T0199500ZS and BnaC06T0206500ZS) were significantly regulated by IAA or GA treatment. And the significant effects of BnaA07T0199500ZS variation on pod shattering resistance were also demonstrated in present study. These results could open a new window for insight into the role of BnaGH28 genes on pod shattering resistance in rapeseed.

Social Impact Statement Tomato fruit is an important and popular commodity producing $95.62 billion worldwide. Tomato fruit losses in the supply chain vary between 25% and 42% depending on the production area and the availability of postharvest technologies. For many decades, conventional tomato breeding programs have focused on extending the shelf‐life of fresh‐market varieties. However, in many instances, consumer‐based quality traits were not considered a priority. Consumers are now demanding safe, nutrient‐rich, high‐flavor, and convenient fruit. Here, we demonstrate the use of gene editing to improve fruit shelf‐life and positively impact quality, which can help significantly reduce tomato fruit losses and meet consumer expectations. Summary Finding alternative ways to extend tomato fruit shelf‐life without reducing the quality is critical to ensure the accessibility and likeability of this commodity worldwide. Improving fruit firmness in tomato fresh‐market varieties directly impacts their shelf‐life potential. We simultaneously knocked out two pectin‐degrading enzymes, polygalacturonase (SlPG2a) and pectate lyase (SlPL), key for tomato fruit softening. We expected this gene‐editing approach to result in longer‐lasting fruit without negatively impacting consumer‐based quality attributes. By generating the double clustered regularly interspaced short palindromic repeats (CRISPR) knockout PGPL, we evaluated the combined functions of SlPG2a and SlPL on fruit quality, including shelf‐life attributes like firmness and water loss, fruit marketability, and disease incidence. We also assessed additional attributes impacting consumer acceptance, such as taste and aroma. We revealed that the enzymes SlPG2a and SlPL act additively, significantly impacting fruit firmness and shelf‐life, with the double CRISPR knockout PGPL outperforming the wild‐type fruit. Additionally, fruit quality traits, such as sugar: acid ratio, aroma volatiles, and skin color, were improved or not affected in the double CRISPR knockout PGPL compared to the wild‐type. The discoveries of this research provide new insights into the influence of pectin backbone degradation on fruit physiology and postharvest quality, which can be used in crop improvement programs to make fruit more resilient in the supply chain without compromising quality.

Rapeseed (Brassica napus L.), accounts for nearly 16% of vegetable oil, is the world's second produced oilseed. However, pod shattering has caused significant yield loses in rapeseed production, particularly during mechanical harvesting. The GH28 genes can promote pod shattering by changing the structure of the pod cell wall in Arabidopsis. However, the role of the GH28 gene family in rapeseed was largely unknown. Therefore, a genome-wide comprehensive analysis was conducted to classify the role of GH28 gene family on rapeseed pod shattering. A total of 37 BnaGH28 genes in the rapeseed genome were identified. These BnaGH28s can be divided into five groups (Group A-E), based on phylogenetic and synteny analysis. Protein property, gene structure, conserved motif, cis-acting element, and gene expression profile of BnaGH28 genes in the same group were similar. Specially, the expression level of genes in group A-D was gradually decreased, but increased in group E with the development of silique. Among eleven higher expressed genes in group E, two BnaGH28 genes (BnaA07T0199500ZS and BnaC06T0206500ZS) were significantly regulated by IAA or GA treatment. And the significant effects of BnaA07T0199500ZS variation on pod shattering resistance were also demonstrated in present study. These results could open a new window for insight into the role of BnaGH28 genes on pod shattering resistance in rapeseed. [ABSTRACT FROM AUTHOR]

Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization. Our previous work confirmed that Camellia oleifera can produce natural 2n pollen, and it is possible to induce the 2n pollen formation by high temperature treatment. This study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced 2n pollen formation in C. oleifera. We found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45 °C with 4 h at the prophase I stage of the pollen mother cells (PMCs). Meanwhile, high temperature significantly decreased the yield and fertility of 2n pollen. Through the observation of meiosis, abnormal chromosome and cytological behaviour was discovered under high-temperature treatment, and we confirmed that the formation of 2n pollen is caused by abnormal cell plate. Based on weighted gene co-expression network analysis, fifteen hub genes related to cell cycle control were identified. After male flower buds were exposed to heat shock, polygalacturonase gene (CoPGX3) was significantly upregulated. We inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin, which leads to an abnormal cell plate. Furthermore, abnormal cytokinesis resulted in the formation of dyads and triads, and PMCs divided to produce 2n pollen. Our findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of C. oleifera. [ABSTRACT FROM AUTHOR]

The postharvest softening and corresponding quality deterioration of blueberry fruits are crucial factors that hinder long-distance sales and long-term storage. Cold plasma (CP) is an effective technology to solve this, but the specific mechanism of delaying fruit softening remains to be revealed. Here, this study found that CP significantly improved blueberry hardness. Physiological analysis showed that CP regulated the dynamic balance of reactive oxygen species (ROS) to maintain hardness by increasing antioxidant content and antioxidant enzyme activity, resulting in a 12.1% decrease in the H2O2 content. Transcriptome analysis revealed that CP inhibited the expression of cell wall degradation-related genes such as the pectin hydrolase gene and cellulase gene, but up-regulated the genes of the ROS-scavenging system. In addition, the resistance genes in the MAPK signaling pathway were also activated by CP in response to fruit ripening and softening and exhibited positive response characteristics. These results indicate that CP can effectively regulate the physiological characteristics of blueberries at a genetic level and delay the softening process, which is of great significance to the storage of blueberries. [ABSTRACT FROM AUTHOR]

Social Impact Statement: Tomato fruit is an important and popular commodity producing $95.62 billion worldwide. Tomato fruit losses in the supply chain vary between 25% and 42% depending on the production area and the availability of postharvest technologies. For many decades, conventional tomato breeding programs have focused on extending the shelf‐life of fresh‐market varieties. However, in many instances, consumer‐based quality traits were not considered a priority. Consumers are now demanding safe, nutrient‐rich, high‐flavor, and convenient fruit. Here, we demonstrate the use of gene editing to improve fruit shelf‐life and positively impact quality, which can help significantly reduce tomato fruit losses and meet consumer expectations. Summary: Finding alternative ways to extend tomato fruit shelf‐life without reducing the quality is critical to ensure the accessibility and likeability of this commodity worldwide. Improving fruit firmness in tomato fresh‐market varieties directly impacts their shelf‐life potential. We simultaneously knocked out two pectin‐degrading enzymes, polygalacturonase (SlPG2a) and pectate lyase (SlPL), key for tomato fruit softening. We expected this gene‐editing approach to result in longer‐lasting fruit without negatively impacting consumer‐based quality attributes.By generating the double clustered regularly interspaced short palindromic repeats (CRISPR) knockout PGPL, we evaluated the combined functions of SlPG2a and SlPL on fruit quality, including shelf‐life attributes like firmness and water loss, fruit marketability, and disease incidence. We also assessed additional attributes impacting consumer acceptance, such as taste and aroma.We revealed that the enzymes SlPG2a and SlPL act additively, significantly impacting fruit firmness and shelf‐life, with the double CRISPR knockout PGPL outperforming the wild‐type fruit. Additionally, fruit quality traits, such as sugar: acid ratio, aroma volatiles, and skin color, were improved or not affected in the double CRISPR knockout PGPL compared to the wild‐type.The discoveries of this research provide new insights into the influence of pectin backbone degradation on fruit physiology and postharvest quality, which can be used in crop improvement programs to make fruit more resilient in the supply chain without compromising quality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Chemistry & Biotechnology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pectinase, a kind of hydrolase, mainly contains polygalacturonase, pectinase, and pectin lyase, which can hydrolyze pectin to generate galacturonide and is widely used in industry. At present, pectinase's activity is still relatively low. Hyperactive pectinase was produced with solid-phase fermentation and a tray bioreactor using the novel strain Aspergillus sp. CM96 in this study. This pectinase's activity can reach 17,000 U·g−1 after fermentation with a tray bioreactor, an increase of 86% compared to that obtained using flask liquid fermentation. The pectinase was purified and its characteristics were explored. Additionally, during pectinase fermentation, the activities of protease, glucanase, and cellulase were also determined to reach 7000, 8000, and 3000 U·g−1. The enzyme mixture was used to improve substrate digestion efficiency in 144 Soviet white pigs after adding a 0.05% cocktail enzyme for 38 days. The results showed that the average daily gain (ADG) increased by 139.41 ± 1.04 g·day−1, while the average daily feed intake (ADFI) and the feed conversion rate (FCR) decreased by 19.82 ± 1.64 g·day−1 and 0.07 ± 0.01 in 38 days, which indicated that the addition of hyperactive pectinase from the strain CM96 can increase nutrient digestibility and improve feed efficiency. [ABSTRACT FROM AUTHOR]

In this work, the application of pectinase enzymes to clarify glucose syrups produced from corn fiber was studied. The enzymatic activity and kinetic parameters of the pectinase enzyme used were quantified. A specific activity of 5,528 U/mg protein, a maximum rate of 19151 U/mL, and a Michaelis-Menten constant of 1,656 mg/mL were obtained. The syrup was prepared by hydrolyzing corn fiber at 50°C and 180 rpm, and a central composite design was performed for the clarification step to find the optimal conditions of enzyme-substrate ratio and agitation. The syrup was heated to a temperature of 50°C, and an enzyme substrate ratio between 2.5 to 4.5 U/mL of syrup and agitation, varying between 215 to 285 rpm, was applied. The conditions to maximize the clarification of corn fiber syrup were determined to be an enzyme substrate ratio of 3.716 U/mL syrup and agitation of 267 rpm. These conditions were validated by taking the syrup from clarity of 65.8% to 88.1%, demonstrating that the methodology used presents advantages in the syrup clarification process. A physicochemical characterization of the corn fiber used to prepare the syrups was carried out, which presented a content of 12.90%, 23.33%, 13.4%, and 0.36% of cellulose, hemicellulose, lignin and pectin, respectively.

Abstract Chlorophyll degradation is an important physiological process and is essential for plant growth and development. However, how chlorophyll degradation is controlled at the cellular and molecular level remains largely elusive. Pectin is a main component of the primary cell wall, and polygalacturonases (PGs) is a group of pectin-hydrolases that cleaves the pectin backbone and release oligogalacturonide. Whether and how PGs affect chlorophyll degradation metabolism and its association with ethylene (ETH) have not been reported before. Here, we report a novel function of PG in a mutant ‘high chlorophyll content1’ hcc1, which displayed a decrease in growth and yield. Our morphological, biochemical and genetic analyses of hcc1, knockout lines and complementation lines confirm the function of HCC1 in chlorophyll degradation. In hcc1, the PG activity, ETH content and D-galacturonic acid (D-GA) was significantly decreased and showed an increase in the thickness of the cell wall. Exogenous application of ETH and D-GA can increase ETH content and induce the expression of HCC1, which further can successfully induce the chlorophyll degradation in hcc1. Together, our data demonstrated a novel function of HCC1 in chlorophyll degradation via the ETH pathway.

The plant-parasitic nematodes are considered as one of the most destructive pests, from which the migratory and sedentary endoparasitic plant parasitic nematodes infect more than 4000 plant species and cause over $100 billion crop losses annually worldwide. These nematodes use multiple strategies to infect their host and to establish a successful parasitism inside the host such as cell-wall degradation enzymes, inhibition of host defense proteins, and molecular mimicry. In the present study, the main parasitism-associated gene families were identified and compared between the migratory and sedentary endoparasitic nematodes. The results showed that the migratory and sedentary endoparasitic nematodes share a core conserved parasitism mechanism established throughout the evolution of parasitism. However, genes involved in pectin degradation and hydrolase activity are rapidly evolving in the migratory endoparasitic nematodes. Additionally, cell-wall degrading enzymes such as GH45 cellulases and pectate lyase and peptidase and peptidase inhibitors were expanded in the migratory endoparasitic nematodes. The molecular mimicry mechanism was another key finding that differs between the endoparasitic and sedentary parasitic nematodes. The PL22 gene family, which is believed to play a significant role in the molecular mechanisms of nematode parasitism, has been found to be present exclusively in migratory endoparasitic nematodes. Phylogenetic analysis has suggested that it was de novo born in these nematodes. This discovery sheds new light on the molecular evolution of these parasites and has significant implications for our understanding of their biology and pathogenicity. This study contributes to our understanding of core parasitism mechanisms conserved throughout the nematodes and provides unique clues on the evolution of parasitism and the direction shaped by the host. [ABSTRACT FROM AUTHOR]

Polygalacturonase-inhibiting proteins (PGIPs) interact with pathogen-derived polygalacturonases to inhibit their virulence-associated plant cell wall-degrading activity but stimulate immunity-inducing oligogalacturonide production. Here we show that interaction between Phaseolus vulgaris PGIP2 (PvPGIP2) and Fusarium phyllophilum polygalacturonase (FpPG) enhances substrate binding, resulting in inhibition of the enzyme activity of FpPG. This interaction promotes FpPG-catalyzed production of long-chain immunoactive oligogalacturonides, while diminishing immunosuppressive short oligogalacturonides. PvPGIP2 binding creates a substrate binding site on PvPGIP2-FpPG, forming a new polygalacturonase with boosted substrate binding activity and altered substrate preference. Structure-based engineering converts a putative PGIP that initially lacks FpPG-binding activity into an effective FpPG-interacting protein. These findings unveil a mechanism for plants to transform pathogen virulence activity into a defense trigger and provide proof of principle for engineering PGIPs with broader specificity. [ABSTRACT FROM AUTHOR]

Bacterial isolates collected from the environment were screened for pectinolytic activity, and a strain with the highest activity was selected and identified as Bacillus subtilis Mz‐12. The presence of pectin hydrolase, lyase, and esterase activities was confirmed. Pectinase was purified and characterized. Enzyme production was optimized with respect to temperature, pH, and growth medium. Enzyme stability and activity were characterized under different temperatures and pH values. The results showed that this strain was capable of producing high yields of pectinase in commercial medium (Pharmamedia) 24.6 U/mL compared to other media. The purified pectinase of 22.3 kDa produced was constitutive in nature. The isolated enzyme from this strain displayed a wide range of temperature and pH stability, with the optimal activity observed at pH 9.0 and 50°C. These results indicate that the B. subtilis Mz‐12 strain is a favorable candidate for industrial enzyme production. The use of Pharmamedia is reported for first time for pectinase production. [ABSTRACT FROM AUTHOR]

A dynamic plant architecture is the basis of plant adaptation to changing environments. Although many genes regulating leaf rolling have been identified, genes directly associated with water homeostasis are largely unknown. Here, we isolated a rice mutant, dynamic leaf rolling 1 (dlr1), characterized by ‘leaf unfolding in the morning-leaf rolling at noon-leaf unfolding in the evening’ during a sunny day. Water content was decreased in rolled leaves and water sprayed on leaves caused reopening, indicating that in vivo water deficiency induced the leaf rolling. Map-based cloning and expression tests demonstrated that an A1400G single base mutation in Oryza sativa Polygalacturonase 1 (OsPG1)/PHOTO-SENSITIVE LEAF ROLLING 1 (PSL1) was responsible for the dynamic leaf rolling phenotype in the dlr1 mutant. OsPG1 encodes a polygalacturonase, one of the main enzymes that degrade demethylesterified homogalacturonans in plant cell walls. OsPG1 was constitutively expressed in various tissues and was enriched in stomata. Mutants of the OsPG1 gene exhibited defects in stomatal closure and decreased stomatal density, leading to reduced transpiration and excessive water loss under specific conditions, but had normal root development. Further analysis revealed that mutation of OsPG1 led to reduced pectinase activity in the leaves and increased demethylesterified homogalacturonans in guard cells. Our findings reveal a mechanism by which OsPG1 modulates water homeostasis to control dynamic leaf rolling, providing insights for plants to adapt to environmental variation. [ABSTRACT FROM AUTHOR]

The cost of enzyme is high due to mostly pure carbon and nitrogen sources. Thus, there is a still need for exploring alternative feedstock to enhance enzyme production and reduce the cost. In this study, proportions of apple pomace, orange peels, and hazelnut shells were formulated by the extreme vertices mixture design (EVMD) method in an attempt to enhance co-production of bacterial pectinase and cellulase enzymes in comparison to production medium with single feedstock. Bacillus subtilis was grown in fermentation media containing acid-pretreated feedstock and minerals at initial pH of 7.0 and 30°C for 72 h. Analysis of results from EVMD resulted in a mix of 20% apple pomace, 30% orange peels, and 50% hazelnut shells as optimal, which provided 8.27 U/mL of pectinase and 0.5 U/mL of cellulase under experimentation. These results implied 40% increase in pectinase but no change in cellulase production compared to the pectinase (5.93 U/mL) and cellulase (0.49 U/mL) obtained with hazelnut shell hydrolysate medium. It was also found that hazelnut shells gave slightly higher pectinase than apple pomace and orange peel media. This study proves the use of food processing wastes in mixed form rather than separate feedstock for enhancing pectinase production. [ABSTRACT FROM AUTHOR]

Peach (Prunus persica (L.) Batsch) fruit are susceptible to chilling injury that is often manifested as browning of the internal flesh. As the ethylene antagonist, 1-methylcyclopropene (1-MCP) is an important contributor to resist chilling stress during peach (Prunus persica (L.) Batsch) storage at low temperatures, but the molecular mechanism of it is still elusive. The study examined in detail the effects of two concentrations (1 and 2 μL·L−1) of 1-MCP on alleviating chilling injury (CI) of postharvest peach fruit stored at 4 ± 0.5°C. The results showed that although all treatments relieved CI, treatment with 1 μL·L−1 more effectively alleviated CI symptoms of postharvest peach fruit than 2 μL·L−1. The internal browning (IB) and weight loss were significantly inhibited by 1 μL·L−1 1-MCP. Lower concentration of 1-MCP maintained normal softening by decreasing the gene expression of expansin (Exp) 1,3, polygalacturonase (PG) 3, and pectate lyase (PLY) 1, 2, 3 and increased the content of soluble sugar during the whole storage period. Meanwhile, the activities of polygalacturonase, pectinmethylesterase (PME), and endo-1,4-β-glucanase (EGase) were reduced by lower concentration of 1-MCP. Our results demonstrate that 1-MCP inhibited CI by suppressing the degradation of cell wall. This study provides a theoretical basis for revealing that 1-MCP alleviates chilling injury in peach fruit. [ABSTRACT FROM AUTHOR]

The high susceptibility of raspberries to softening restricts the development of the raspberry industry. The primary causes of fruit softening are the breakdown of components linked to the cell wall and the destruction of the cell wall structure itself. Polygalacturonase (PG), a key enzyme that catalyzes pectin degradation, plays a critical role in fruit softening. However, there are currently limited studies on the mechanism of PG genes in raspberry fruit softening. In this study, a PG gene, RiPG2, was isolated from raspberry (Rubus idaeus L.). 'Polka' fruits and tomato plants overexpressing RiPG2 were obtained by Agrobacterium tumefaciens-mediated leaf disc transformation to elucidate the role of RiPG2 in fruit softening. The total length of the RiPG2 gene is 1185 bp, and the gene encodes a total of 394 amino acids. The GFP fusion protein was expressed at the chloroplast under laser confocal microscopy, indicating that the RiPG2 protein is localized to the chloroplasts. Phenotypic analysis revealed that the fruit firmness of three strains was considerably less than that of controls, but PG enzyme activity was increased. Overexpression of RiPG2 altered the content of cell wall components, with an increase in water-soluble pectin (WSP) and ion-bound pectin (ISP) but a decrease in protopectin, cellulose, hemicellulose, and covalently bound pectin (CSP). In addition, RiPG2 positively regulated the expression of cell wall metabolism-related genes such as SlEXP1, SlTBG4, SlXTH5, and SlPL. These results suggest that the RiPG2 gene regulates the structure and composition of the cell wall and acts synergistically with other cell wall metabolism-related genes to promote fruit softening. This study provides a new candidate gene for molecular breeding to improve raspberry firmness. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chlorophyll degradation is an important physiological process and is essential for plant growth and development. However, how chlorophyll degradation is controlled at the cellular and molecular level remains largely elusive. Pectin is a main component of the primary cell wall, and polygalacturonases (PGs) is a group of pectin-hydrolases that cleaves the pectin backbone and release oligogalacturonide. Whether and how PGs affect chlorophyll degradation metabolism and its association with ethylene (ETH) have not been reported before. Here, we report a novel function of PG in a mutant 'high chlorophyll content1' hcc1, which displayed a decrease in growth and yield. Our morphological, biochemical and genetic analyses of hcc1, knockout lines and complementation lines confirm the function of HCC1 in chlorophyll degradation. In hcc1, the PG activity, ETH content and D-galacturonic acid (D-GA) was significantly decreased and showed an increase in the thickness of the cell wall. Exogenous application of ETH and D-GA can increase ETH content and induce the expression of HCC1, which further can successfully induce the chlorophyll degradation in hcc1. Together, our data demonstrated a novel function of HCC1 in chlorophyll degradation via the ETH pathway. [ABSTRACT FROM AUTHOR]

The demand for pectinases in the global market has been on the rise in recent years due to their significant biotechnological uses. The present study involves the characterization of a crude alkaline pectinase from Bacillus halodurans LBW 5117 and the demonstration of its bioscouring potential. The enzyme was an endo polygalacturonase (PGase LBW 5117) that was brown and had a slight fermentation odor. It exhibited an activity of 0.21 U/ml and retained 67, 90.5, 95.2, and 95.2 % of this activity after 1 year of storage at -20, 4, 20, and 30 °C, respectively. Its operational pH and temperature ranged between 10.2 - 11.0 (optimum, 10.5) and 45 - 57 oC (optimum 50 °C), respectively. Metal ions e.g., K+, Ca2+, Mg2+, Fe3+, Cu2+, Na+, Mn2+, and Zn2+ either stimulated or did not significantly affect its activity at 1 mM. The enzyme retained only 15 % of its activity after 8 h of incubation at 50 °C, but this improved to 200 % in the presence of 1.5 mM Ca2+ and 0.05 mM Tween 20. The enzyme was cellulase-free and hydrolyzed pectin in an endo-manner. Moreover, when used under the established optimized operating conditions, it degraded and eliminated pectin (and other non-cellulosic hydrophobic impurities that adhere to it) from woven cotton (weight loss = 0.68 %) and produced a more hydrophilic fabric with improved wettability for water (drop test = 10 sec) and dye (capillary rise test = 28 mm after 30 min). This result shows that PGase LBW 5117 possesses good operational properties, potentially making it a good bioscouring agent. It is, however, recommended that the bioscouring process be optimized, and its effectiveness be compared with that of standard bio-and/or chemical-scouring process(es). [ABSTRACT FROM AUTHOR]

Polygalacturonase (PG) is one of the largest families of hydrolytic enzymes in plants. It is involved in the breakdown of pectin in the plant cell wall and even contributes to peel cracks. Here, we characterize PGs and outline their expression profiles using the available reference genome and transcriptome of Akebia trifoliata. The average length and exon number of the 47 identified AktPGs, unevenly assigned on 14 chromosomes and two unassembled contigs, were 5399 bp and 7, respectively. The phylogenetic tree of 191 PGs, including 47, 57, 51, and 36 from A. trifoliata, Durio zibethinus, Actinidia chinensis, and Vitis vinifera, respectively, showed that AktPGs were distributed in all groups except group G and that 10 AktPGs in group E were older, while the remaining 37 AktPGs were younger. Evolutionarily, all AktPGs generally experienced whole-genome duplication (WGD)/segmental repeats and purifying selection. Additionally, the origin of conserved domain III was possibly associated with a histidine residue (H) substitute in motif 8. The results of both the phylogenetic tree and expression profiling indicated that five AktPGs, especially AktPG25, could be associated with the cracking process. Detailed information and data on the PG family are beneficial for further study of the postharvest biology of A. trifoliata. [ABSTRACT FROM AUTHOR]

Rhizopus delemar, an opportunistic fungal pathogen, causes a highly fatal disease, mucormycosis. Spore germination is a crucial mechanism for disease pathogenesis. Thus, exploring the molecular mechanisms of fungal germination would underpin our knowledge of such transformation and, in turn, help control mucormycosis. To gain insight into the developmental process particularly associated with cell wall modification and synthesis, weighted gene co-expression network analysis (WGCNA) was performed including both coding and non-coding transcripts identified in the current study, to find out the module of interest in the germination stages. The module-trait relationship identified a particular module to have a high correlation only at the resting phase and further analysis revealed the module to be enriched for protein phosphorylation, carbohydrate metabolic process, and cellular response to stimulus. Moreover, co-expression network analysis of highly connected nodes revealed cell wall modifying enzymes, especially those involved in mannosylation, chitin-glucan crosslinking, and polygalacturonase activities co-expressing and interacting with the novel lncRNAs among which some of them predicted to be endogenous target mimic (eTM) lncRNAs. Hence, the present study provides an insight into the onset of spore germination and the information on the novel non-coding transcripts with key cell wall–related enzymes as potential targets against mucormycosis. [ABSTRACT FROM AUTHOR]

Jellyfish are economically important organisms in diverse countries, carnivorous organisms that consume various prey (crustaceans, mollusks, bivalves, etc.) and dissolved carbohydrates in marine waters. This study was focused on detecting and quantifying the activity of digestive glycosidases from the cannonball jellyfish (Stomolophus sp. 2) to understand carbohydrate digestion and its temporal-spatial variation. Twentythree jellyfish gastric pouches were collected in 2015 and 2016 in the Gulf of California in three localities (Las Guásimas, Hermosillo, and Caborca). Nine samples were in intra-localities from Las Guásimas. Chitinase (Ch), β-glucosidase (β-glu), and β-N-acetylhexosaminidase (β-NAHA) were detected in the gastric pouches. However, cellulase, exoglucanase, α-amylase, polygalacturonase, xylanase, and κ-carrageenase were undetected. Detected enzymes showed halotolerant glycolytic activity (i = 0-4 M NaCl), optimal pH, and temperature at 5.0 and 30-50 ℃, respectively. At least five β-glucosidase and two β-N-acetylhexosaminidase were detected using zymograms; however, the number of proteins with chitinase activity is not precise. The annual variation of cannonball jellyfish digestive glycosidases from Las Guásimas between 2015-2016 does not show significant differences despite the difference in phytoplankton measured as chlorophyll α (1.9 and 3.4 mg/m³, respectively). In the inter-localities, the glycosidase activity was statistically different in all localities, except for β-Nacetylhexosaminidase activity between Caborca and Hermosillo (3,009.08 ± 87.95 and 3,101.81 ± 281.11 mU/g of the gastric pouch, respectively), with chlorophyll α concentrations of 2.6, 3.4 mg/m³, respectively. For intra-localities, the glycosidase activity did not show significant differences, with a mean chlorophyll α of 1.3 ± 0.1 mg/m³. These results suggest that digestive glycosidases from Stomolophus sp. 2 can hydrolyze several carbohydrates that may belong to their prey or carbohydrates dissolved in marine waters, with salinity over-0.6MNaCl and diverse temperature (4-80 ℃) conditions. Also, chlorophyll α is related to glycosidase activity in both seasons and inter-localities, except for chitinase activity in an intra-locality (Las Guásimas). [ABSTRACT FROM AUTHOR]

The addition of pectinase enzymes during the maceration stage of grape skins in order to improve the extraction yields and color of red wines is a common practice in many wineries. The objective of this work was to study in depth the changes that occurred in the aminoacidic, volatile, and phenolic compositions of Cabernet Sauvignon wines fermented with a Saccharomyces cerevisiae strain genetically modified with the gene encoding for endopolygalacturonase (PGU1) in transcriptional fusion with the promoter of the phosphoglycerate kinase (PGK1) gene, both from S. cerevisiae origin. A higher yield extraction of wine was obtained in wines fermented with the modified strain (PW), increasing by around 6.1% compared to the control wine (CW). Moreover, there was a 40% decrease in the malic acid content in the PW, thus suggesting that this modified yeast could be investigated as a malic acid-reducing agent. There were slight differences in other aroma volatile compounds studied as well as in the phenolic content. However, there was a considerable increase in the amino acid content in the PW.

Fruit softening is a prominent attribute governing both longevity on shelves and commercial worth. Polygalacturonase (PG) plays a major role in strawberry fruit softening. However, the PG gene family in strawberry has not been comprehensively analyzed. In this study, 75 FaPG genes were identified in the octoploid strawberry genome, which were classified into three groups according to phylogenetic analysis. Subcellular localization prediction indicated that FaPGs are mostly localized to the plasma membrane, cytoplasm, and chloroplasts. Moreover, the expression of FaPGs during strawberry development and ripening of ‘Benihoppe’ and its softer mutant was estimated. The results showed that among all 75 FaPGs, most genes exhibited low expression across developmental stages, while two group c members (FxaC_21g15770 and FxaC_20g05360) and one group b member, FxaC_19g05040, displayed relatively higher and gradual increases in their expression trends during strawberry ripening and softening. FxaC_21g15770 was selected for subsequent silencing to validate its role in strawberry softening due to the fact that it exhibited the highest and most changed expression level across different developmental stages in ‘Benihoppe’ and its mutant. Silencing FxaC_21g15770 could significantly improve strawberry fruit firmness without affecting fruit color, soluble solids, cellulose, and hemicellulose. Conversely, silencing FxaC_21g15770 could significantly suppress the expression of other genes related to pectin degradation such as FaPG-like, FaPL, FaPME, FaCX, FaCel, FaGlu, FaXET, and FaEG. These findings provide basic information on the FaPG gene family for further functional research and indicate that FxaC_21g15770 plays a vital role in strawberry fruit softening.

Mealy peaches are dry and flavorless, which reduces their consumer acceptance. A deeper understanding of the mechanism underlying mealiness is crucial to enhancing peach fruit quality. In this study, comparative profiling was conducted on CP13, CP14, CM, and RM peaches. Sensory evaluation indicated that CP13 and CM are non-mealy clingstone and freestone peaches, respectively, and CP14 and RM are mealy freestone peaches. Both CP13 and CP14, identified as stony hard (SH) peaches, exhibited minimal ethylene release, whereas CM and RM, identified as melting flesh (MF) peaches, released high amounts of ethylene during the ripening process. Scanning electron microscopy (SEM) microstructure observation indicated that cells in the flesh tissue of mealy peaches, CP14 (SH) and RM (MF), were intact and separated, with large intercellular spaces and irregular arrangements. The main factor that promotes mealiness is differences in pectin metabolism, which impact cell wall composition. The fluctuations in polygalacturonase (PG) and pectin methylesterase (PME) activity between mealy and non-mealy peaches were the main factor contributing to mealiness. However, the changes in cell wall metabolism that caused these fluctuations did not have a clear direction. Using transcriptome analysis and weighted gene co-expression network analysis (WGCNA), we were able to identify forty differentially expressed genes (DEGs) that are associated with mealy patterns. Among these DEGs, genes encoding PG were significantly upregulated in mealy peaches (CP14 and RM) compared to non-mealy peaches (CP13 and CM). PpPG1 was the main effector gene for mealiness, while PpPG2, PpEGase2, PpEXP1, PpEXP3, PpAGP2, PpIAA4, and PpABA2 were identified as candidate genes regulating peach mealiness. These findings provide a solid experimental basis for understanding the textual distinctions between mealy and non-mealy peaches.

Fresh blackberry fruits have easily perishable tissue and therefore have a very short postharvest storage life, although customers and marketers desire a longer shelf life. The ever-increasing demand of the world population for residue-free functional foods has motivated scientists to investigate environmentally friendly methodologies for the quality extension of perishable products like fresh blackberries. The present study was performed to determine the influences of UV-C treatment and chitosan coating on the extension of postharvest bioactive compounds and the marketable quality of fresh blackberry (Rubus fructicosus L.) fruits. Organically produced 'Jumbo' blackberry fruits were sorted into four equal groups for postharvest treatments: (a) untreated berries as a control, (b) UV-C irradiation for 5 min at 254 nm, (c) coating with 1% chitosan, and (d) UV-C + chitosan. After these treatments, blackberry fruits were stored in polypropylene cups of 12 × 15 cm at 1 ± 0.5 ℃ and 85% relative humidity for 14 days. Blackberries were sampled on the first day (day 0) and the 4th, 7th, 10th, and 14th days during cold storage. At the end of the 14-day storage period, the greatest weight loss was determined in control fruits (3.04%) while the lowest was found for UV-C irradiation + chitosan coating (1.59%). The activity of the polygalacturonase enzyme was significantly restricted by all treatments with the highest effect of UV-C + chitosan treatment, which also provided the best visual quality during storage. UV-C + chitosan was also the best treatment for delaying the changes in soluble solid content, titratable acidity, L*, C*, h°, antioxidants, ascorbic acid, and total anthocyanins. Overall, the findings revealed that postharvest chitosan coating at 1% concentration following UV-C irradiation at 254 nm for 5 min could be proposed as an effective, safe, healthy, ecofriendly, and sustainable strategy for extending the bioactive compounds and marketable quality of fresh blackberry fruits. [ABSTRACT FROM AUTHOR]

Kiwifruits are often exposed to various temperature fluctuations (TFs) during postharvest transportation and storage. To evaluate the effect of TFs on the qualities of kiwifruits during storage, kiwifruits were stored at 2 °C, 2 °C or 5 °C (TF2 °C–5 °C, alternating every 12 h), 2 °C or 7 °C (TF2 °C–7 °C, alternating every 12 h) for 3 d before long time storage at 2 °C. Observations revealed that kiwifruits stored at a constant 2 °C showed the lowest loss of weight and vitamin C because of minimized ethylene production and respiratory rate compared with that of TF2 °C–5 °C and TF2 °C–7 °C. Moreover, the results of RT-qPCR verified that the expression levels of genes encoding polygalacturonase, β-galacturonidase, and pectin methylesterase were significantly increased by the treatment of TF. Hence, TF accelerated the degradation of cell walls, softening, translucency, and relative conductivity of the flesh of kiwifruits. In addition, the impact of TF2 °C–7 °C on kiwifruits was more significant relative to TF2 °C–5 °C. The present study provides a theoretical basis for kiwifruit during cold storage. [ABSTRACT FROM AUTHOR]

The aim of the study was to develop a biotechnological approach for the green recovery of chlorophyll from spinach, to be used as a natural food colorant. The plant matrix was characterized in terms of cell wall polysaccharide composition, and a tailored enzymatic mix based on cellulase (40%) xylanase (41%) and polygalacturonase (19%) was formulated. The process variables (temperature (°C), time (h), enzyme mix dose (U/g), zinc concentration (ppm), and buffer/substrate ratio (B/S)) and their interactions were studied by response surface methodology. The overlay plot made it possible to identify the process conditions (T: 25 °C, Zn: 150 ppm e B/S: 17.5, t: <2 h and enzyme mix dose between 12 and 45 U/g) to maximize the amount of chlorophyll, and concurrently, the quality of the green color of the extract. Finally, the novel colorant was applied in the production of a real food. [ABSTRACT FROM AUTHOR]

Cold plasma (CP) is a green and efficient preservation technology, but its effect on preventing the postharvest softening of fruits and vegetables is still unclear, and the effects of different CP intensities on the postharvest softening of winter jujubes (Ziziphus jujuba Mill. cv. Dongzao) have been little studied. In this study, we investigated the effects of different CP intensities (0 kV, 40 kV, and 80 kV) on the postharvest storage quality of winter jujubes and the activities of key enzymes related to softening during storage. The results showed that compared with the control group, the contents of firmness, total soluble solids (TSS), titratable acidity (TA), and vitamin C (VC) in the CP treatment group were higher and the respiratory intensity and weight loss rate were lower. In addition, CP treatment can also inhibit the degradation of protopectin and cellulose and the accumulation of soluble pectin. Moreover, CP treatment inhibited the activities of polygalacturonase (PG), pectin methyl esterase (PME), 3α-L-arabinoside (α-L-Af), 4β-galactosidase (β-gal), cellulase (Cx), and β-glucosidase (β-Glu). This shows that CP treatment has a positive effect on the preservation of winter jujubes, and the preservation effect of the 80 kV treatment was better than that of the 40 kV treatment. This provides a certain basis for cold plasma treatment in the preservation of winter jujubes. [ABSTRACT FROM AUTHOR]

Papaya (Carica papaya L.) is a climacteric fruit, and its quality will rapidly decrease after ripening. Hence, the storage life of its fruit is short. D-limonene is a terpene compound in citrus essential oil and has antibacterial and antioxidant properties. The addition of D-limonene in edible coating can delay volatilization, prevent microorganism and pathogen invasion, decrease water loss, inhibit softening, decrease gas exchange, and extend the storage life of fruits. In this study, 0.25%, 0.5%, and 1% D-limonene nanoemulsion coatings were used for post-harvest immersion treatment of "Tainung No. 2" papayas and its effects on appearance, chlorophyll content, respiration rate, ethylene production, pectin methylesterase, polygalacturonase activity, decay loss, firmness, total soluble solid, titratable acidity, ascorbic acid, and total plate count were investigated. After the papayas were treated with 0.5% D-limonene nanoemulsion coating, polygalacturonase and pectin methylesterase activities decreased, fruit firmness was maintained, and ascorbic acid content was high. On the last day of storage, polygalacturonase and pectin methylesterase activities were 0.01 and 0.02 U/kg FW lower than the control group, respectively; firmness was higher than the control group by 1.75 N, and ascorbic acid content was higher than the control group by 31.97 mg/100 g FW. On Day 2, the treatment showed delay in total soluble solid accumulation and chlorophyll degradation, consequently delaying the color change in fruits. The coating decreased decay loss by 40% on Day 2, decreased respiration rate by 97.0 mg CO2 kg−1 h−1, and ethylene production by 5.7 µL kg−1 h−1 on Day 2. Simultaneously, the coating decreased the total plate count and resulted in a good appearance. Fruits coated with a 1% D-limonene nanoemulsion coating showed defects in color change. In summary, 0.5% D-limonene nanoemulsion coating delayed "Tainung No. 2" papaya ripening and decreased microbial infection, consequently extending its storage life. [ABSTRACT FROM AUTHOR]

Understanding the essential role of ethylene release in the long-distance transportation of climacteric fruits, like mangoes, is crucial. This study aimed to investigate the relationship between ethylene release and the postharvest ripening of mangoes. The research employed innovative ripening sachets to control the ripening process, specifically focusing on extending shelflife and enhancing quality. Dashehari mangoes exposed to ripening sachets releasing 100 ppm of ethylene exhibited improved quality attributes. The 6th day post-treatment recorded the highest total soluble solids (TSS) at 17.37 °B and the lowest acidity at 0.23%. Ascorbic acid content and firmness were measured at 22.50 mg 100 gm-1 and 2.63 kg cm-2, respectively. Polygalacturonase activity in mango pulp (11.80,08.56 U mL-1 min-1) and peel (34.00, 20.30 U mL-1 min-1) peaked on the 4th and 6th day, respectively. The peel colour L* value increased from 2nd to 6th day after treatment, whereas the a* and b* values increased from 2nd to 4th day and the a* and b* values gradually decreased on 6th day in all the treatments except T4. The study suggests that ripening sachets have the potential to effectively regulate mango ripening and preserve fruit quality for an extended period. [ABSTRACT FROM AUTHOR]

In plants, polygalacturonase-inhibiting proteins (PGIPs) play critical roles for resistance to fungal disease by inhibiting the pectin-depolymerizing activity of endopolygalacturonases (PGs), one type of enzyme secreted by pathogens that compromises plant cell walls and leaves the plant susceptible to disease. Here, the interactions between PGIPs from Phaseolus vulgaris (PvPGIP1 and PvPGIP2) and PGs from Aspergillus niger (AnPG2), Botrytis cinerea (BcPG1 and BcPG2), and Fusarium moniliforme (FmPG3) were reconstituted through a yeast two hybrid (Y2H) system to investigate the inhibition efficiency of various PvPGIP1 and 2 truncations and mutants. We found that tPvPGIP2_5-8, which contains LRR5 to LRR8 and is only one-third the size of the full length peptide, exhibits the same level of interactions with AnPG and BcPGs as the full length PvPGIP2 via Y2H. The inhibitory activities of tPvPGIP2_5-8 on the growth of A. niger and B. cinerea were then examined and confirmed on pectin agar. On pectin assays, application of both full length PvPGIP2 and tPvPGIP2_5-8 clearly slows down the growth of A. niger and B. cinerea. Investigation on the sequence-function relationships of PGIP utilizing a combination of site directed mutagenesis and a variety of peptide truncations suggests that LRR5 could have the most essential structural feature for the inhibitory activities, and may be a possible target for the future engineering of PGIP with enhanced activity. This study highlights the potential of plant-derived PGIPs as a candidate for future in planta evaluation as a pest control agent.