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Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department 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.)

Abstract Tea gray blight disease is a significant threat to the tea industry. In this study, a biological activity approach was utilized to investigate the efficacy of green fungicides from Magnolia officinalis stem bark against Neopestalotiopsis ellipsospora. The active compounds were isolated and purified, and their structures were elucidated. In vitro and in vivo activity screenings revealed that the n-hexane extract, which contained magnolol and honokiol, exhibited strong activity against N. ellipsospora, showing complete inhibition at 100 mg/L. The EC50 values of magnolol and honokiol were 5.11 and 6.09 mg/L, respectively. Mechanistically, magnolol was found to disrupt N. ellipsospora invasion by damaging the cell membrane, increasing permeability, and causing leakage of intracellular substances. Transcriptome analysis revealed that magnolol treatment downregulates membrane-related genes and leads to the enrichment of lipid metabolism pathway genes. This study revealed that magnolol inhibits N. ellipsospora growth by affecting lipid metabolism and compromising cell membrane integrity.

In this study, to investigate the effects of melatonin on pericarp browning in rambutan fruit, postharvest ‘Baoyan7’ rambutan fruit was immersed in melatonin solutions at varying concentrations for 15 min, air-dried, and then stored at 25 ℃ for 6 days. The results demonstrated that melatonin treatment at each concentration delayed browning and the decline in the chromaticity a* value of rambutan pericarp, with the most pronounced effect being observed at 0.125 mmol/L melatonin. Physiological and biochemical analyses showed that melatonin treatment at 0.125 mmol/L repressed the increase in relative conductivity (RC) and malondialdehyde (MDA) contents, while retarding the increase in lipoxygenase (LOX), lipase (LPS) and phospholipase D (PLD) activities in rambutan fruit during storage, thereby preserving the integrity of the cell membrane. In addition, treatment with 0.125 mmol/L melatonin increased the contents of nicotinamide adenine dinucleotide (NADH) and flavin dinucleotide (FADH2), enhanced the activities of energy metabolism-related enzymes including succinate dehydrogenase (SDH), cytochromic c oxidase (CCO), H+-ATPase and Ca2+-ATPase, and maintained high levels of adenosine triphosphate (ATP) and energy charge, thus improving cellular energy status. Moreover, this treatment enhanced γ-aminobutyric acid (GABA) content, and maintained high activities of glutamate decarboxylase (GAD) and GABA aminotransferase (GABA-T), thus contributing to enhanced cellular energy supply. These findings suggest that melatonin could retard postharvest browning and senescence in rambutan fruit by modulating membrane lipid and energy metabolisms.

Nitrogen is one of the most essential macronutrients for plant growth and its availability in soil is vital for agricultural sustainability and productivity. However, excessive nitrogen application could reduce the nitrogen use efficiency and produce environmental pollution. Here, we systematically determined the response in lipidome and metabolome in rapeseed during nitrogen starvation. Plant growth was severely retarded during nitrogen deficiency, while the levels of most amino acids were significantly decreased. The level of monogalactosyldiacyglycerol (MGDG) in leaves and roots was significantly decreased, while the level of digalactosyldiacylglycerol (DGDG) was significantly decreased in roots, resulting in a significant reduction of the MGDG/DGDG ratio during nitrogen starvation. Meanwhile, the levels of sulfoquinovosyl diacylglycerol, phosphatidylglycerol and glucuronosyl diacylglycerol were reduced to varying extents. Moreover, the levels of metabolites in the tricarboxylic acid cycle, Calvin cycle and energy metabolism were changed during nitrogen deficiency. These findings show that nitrogen deprivation alters the membrane lipid metabolism and carbon metabolism, and our study provides valuable information to further understand the response of rapeseed to nitrogen deficiency at the metabolism level. [ABSTRACT FROM AUTHOR]

ABSTRACTThe cell membrane forms a fundamental part of all living cells and participates in a variety of physiological processes, such as material exchange, stress response, cell recognition, signal transduction, cellular immunity, apoptosis, and pathogenicity. Here, we review the mechanisms and functions of the membrane structure (lipid components of the membrane and the biosynthesis of unsaturated fatty acids), membrane proteins (transmembrane proteins and proteins contributing to membrane curvature), transcriptional regulation, and cell wall components that influence the virulence and pathogenicity of filamentous fungi.

In order to investigate the effect of preharvest spraying of diethyl aminoethyl hexanoate (DA-6) on membrane lipid metabolism in ‘Kyoho’ grapes during postharvest storage, distilled water (control) and 50 mg/L DA-6 were used to spray grapes at the veraison stage. The grapes were harvested when they were ripe, stored at (0 ± 1) ℃ and relative humidity of 65%–70%, and evaluated for cell membrane related indicators of grape skin after 0, 20, 30, 40, 50, and 60 days. The results showed that compared with the control group, DA-6 treatment effectively inhibited the increase in the relative permeability of cell membrane during postharvest storage, maintained the activities of lipoxygense (LOX), lipase and phospolipase D (PLD), inhibited the decrease of phosphatidylcholine and phosphatidylinositol content and the increase of phosphatidyl acid content, and maintained a high relative content of unsaturated acids such as linoleic acid and linolenic acid as well as saturated fatty acids such as stearic acid, behenic acid, arachidic acid and palmitoleic acid, consequently maintaining the degree of unsaturation of fatty acids at a high level. Additionally, DA-6 treatment suppressed the expression of the LOX, Lipase, and PLD genes. In summary, preharvest spraying of 50 mg/L DA-6 can delay the senescence and prolong the storage period of ‘Kyoho’ grapes by effectively relieving the membrane lipid metabolism during storage.

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology 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.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department 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.)

Abstract The cold‐sensitive peach fruits are prone to chilling injury (CI). γ‐aminobutyric acid (GABA) has been confirmed to effectively improve peaches’ cold tolerance. This research aimed to probe the role of dynamic changes in membrane lipid metabolism in GABA‐mediated peaches’ cold tolerance and reveal the underlying mechanisms based on lipid metabolomics. GABA treatment improved peaches’ cold tolerance by reducing phosphatidic acid (PA) accumulation via inhibiting phospholipid degradation, attenuating PA biosynthesis, and maintaining higher phosphatidylcholine (PC) and phosphatidylethanolamine (PE) levels. Under chilling conditions, GABA treatment protected peaches against low‐temperature stress and delayed CI by maintaining higher PC and PE levels and enhancing the massive accumulation of diacylglycerol (DAG) and triacylglycerol (TAG). This study provides a novel mechanism regulating cold tolerance of postharvest peach fruits.

To investigate the effect of n-butanol on postharvest membrane lipid metabolism of Hami melon (Cucumis melo 'Hami'), the fruits were soaked in a 1.0% solution of n-butanol for 30 min with water as the control. Symptoms of chilling injury were observed regularly, and the indices related to permeability and membrane lipid metabolism of pericarp cells were measured. The results showed that treatment with n-butanol inhibited the increase in chilling injury index, membrane permeability, and malondialdehyde content of Hami melon fruits, promoted an increase in the contents of phosphatidyl alcohol and unsaturated fatty acids, such as linoleic acid, linolenic acid, oleic acid (except 14 d), and erucic acid (28–42 d), and decreased the content of saturated fatty acids, stearic acid (0–28 d), phosphatidic acid (except for 21 d), and the key enzymes of membrane lipid metabolism compared with the control. The activities of phospholipase D (PLD) and lipoxygenase (LOX) and the downregulation of the levels of expression CmPLD-β and CmLOX (42 d only) genes reduced the chilling injury index of Hami melon and alleviated the further expansion of chilling injury symptoms in the fruits. We also cloned the key gene of membrane lipid metabolism CmPLD-β, which was obtained by pre-transcriptome screening of the pericarp. We found that CmPLD-β of Hami melon had the closest affinity with cucumber (CsXP5), indicating that the CmPLD-β gene of Hami melon was functionally similar to that of cucumber. In addition, a two-fold alignment analysis of CmPLD-β and CmXP5 base sequences indicated that the base sequences of the two promoter regions differed from each other. [ABSTRACT FROM AUTHOR]

Cucumber fruit is very sensitive to chilling injury, which rapidly depreciates their commodity value. Herein, the effect of fucoidan treatment on cucumber under cold stress were investigated. Fucoidan treatment of cold-stored cucumber alleviated the occurrence of chilling injury, delayed weight loss, lowered electrolyte leakage and respiration rate, and retarded malondialdehyde accumulation. Different from the control fruit, fucoidan treated fruit showed a high level of fatty acid unsaturated content, fatty acid unsaturation, and unsaturation index and increased ω-FDAS activity, along with upregulated expression levels of CsSAD and CsFAD genes. Fucoidan reduced the phosphatidic acid content and membrane lipid peroxidation, lowered the phospholipase D (PLD) and lipoxygenase (LOX) activity, and downregulated the expression levels of CsPLD and CsLOX genes. Collectively, fucoidan treatment maintained the integrity of cell membrane in cold-stress cucumbers. The results provide a new prospect for the development of fucoidan as a preservative agent in the low-temperature postharvest storage of cucumbers. [ABSTRACT FROM AUTHOR]

The effects of γ-aminobutyric (GABA) on enzymatic browning, storage quality, membrane and reactive oxygen species (ROS) metabolism in fresh-cut stem lettuce were investigated. The results illustrated that GABA treatment delayed browning degree, polyphenol oxidase (PPO) activity and the expression of LsPPO. Meanwhile, higher chlorophyll and ascorbic acid contents were exhibited in GABA-treated stem lettuce, as well as the slower microbial propagation. Further investigation revealed that exogenous GABA application declined malondialdehyde content, electrolyte leakage and the enzyme activities of membrane metabolism, and the expression levels of related genes were also downregulated. In addition, GABA treatment scavenged ROS and strengthened the enzyme activities of ROS metabolism, as well as the expression levels of corresponding genes. Taken together, these findings implied that the repressed enzymatic browning and microbial propagation in GABA-treated stem lettuce were due to the inhibition of ROS accumulation, enhancement of membrane stability and increased resistance to oxidation. • Exogenous GABA inhibited the enzymatic browning of fresh-cut stem lettuce. • GABA treatment maintained the quality in fresh-cut stem lettuce. • GABA application inhibited the microbial propagation in fresh-cut stem lettuce. • GABA treated-fresh-cut stem lettuce exhibited higher membrane stability. • GABA treatment enhanced the antioxidant capacity in fresh-cut stem lettuce. [ABSTRACT FROM AUTHOR]

Postharvest fruit storage and quality is a severe concern for fruit producers, as consumer acceptability and market value are affected by quality attributes. Therefore, strategies to improve fruit quality during storage are crucial. In this study, we investigated the effects of melatonin (MT) treatment on postharvest fruit quality, ascorbate-glutathione metabolism, and membrane lipid metabolism in blueberries. Blueberries were treated with 300 μM of MT solution or distilled water (control) before harvest. After harvest, blueberries were stored at 4 °C and sampled every 4 days to analyze fruit quality parameters. MT treatment effectively reduced decay rate and weight loss rate in blueberry during storage and delayed the decrease in firmness, total soluble solids, titratable acid, anthocyanins, and flavonoids. It furthermore elevated the activities and gene expression of enzymes such as superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, dehydroascorbate reductase, and monodehydroascorbate reductase. Moreover, MT treatment promoted the accumulation of ascorbate–glutathione, NADP, NADPH, and glutathione, increased glutathione (GSH)/glutathione (GSSG) levels, enhanced antioxidant capacity, and decreased oxidized glutathione, H 2 O 2 , dehydroascorbic acid, and superoxide anion levels. Notably, MT treatment inhibited membrane lipid peroxidation in blueberries by inhibiting the mRNA levels and activities of lipoxygenase and phospholipase D. Conclusively, MT reduces blueberry decay during storage by modulating ascorbate–glutathione cycle and membrane lipid metabolism. • Melatonin reduces fruit decay in blueberries. • Melatonin delays the decline in TSS, TA, anthocyanin, and flavonoid content. • Melatonin increases the activity of antioxidant enzymes. • Melatonin enhances ascorbate–glutathione cycle activity. • Melatonin delays the process of membrane lipid metabolism. [ABSTRACT FROM AUTHOR]

To investigate the effect of n-butanol on postharvest membrane lipid metabolism of Hami melon (Cucumis melo ‘Hami’), the fruits were soaked in a 1.0% solution of n-butanol for 30 min with water as the control. Symptoms of chilling injury were observed regularly, and the indices related to permeability and membrane lipid metabolism of pericarp cells were measured. The results showed that treatment with n-butanol inhibited the increase in chilling injury index, membrane permeability, and malondialdehyde content of Hami melon fruits, promoted an increase in the contents of phosphatidyl alcohol and unsaturated fatty acids, such as linoleic acid, linolenic acid, oleic acid (except 14 d), and erucic acid (28–42 d), and decreased the content of saturated fatty acids, stearic acid (0–28 d), phosphatidic acid (except for 21 d), and the key enzymes of membrane lipid metabolism compared with the control. The activities of phospholipase D (PLD) and lipoxygenase (LOX) and the downregulation of the levels of expression CmPLD-β and CmLOX (42 d only) genes reduced the chilling injury index of Hami melon and alleviated the further expansion of chilling injury symptoms in the fruits. We also cloned the key gene of membrane lipid metabolism CmPLD-β, which was obtained by pre-transcriptome screening of the pericarp. We found that CmPLD-β of Hami melon had the closest affinity with cucumber (CsXP5), indicating that the CmPLD-β gene of Hami melon was functionally similar to that of cucumber. In addition, a two-fold alignment analysis of CmPLD-β and CmXP5 base sequences indicated that the base sequences of the two promoter regions differed from each other.

Postharvest harmful pathogenic infestation leads to rapid decay in longan fruit. Compared with P. longanae -infected longans, AEOW alleviated fruit disease severity and diminished the O 2 -. production rate and MDA content. It also increased APX, CAT, and SOD activities, delayed the decrease in the levels of GSH and AsA, as well as the reducing power and DPPH radical scavenging ability, which resulted in a decline in membrane lipid peroxidation in P. longanae -infected longans. Additionally, AEOW reduced LOX, lipase, PI-PLC, PC-PLC, and PLD activities, maintained higher levels of PC, PI, IUFA, USFAs, and U/S, while reducing levels of PA, DAG, SFAs, and CMP. These effects alleviated membrane lipid degradation and peroxidation in P. longanae -infected longans. Consequently, AEOW effectively maintained membrane integrity via improving antioxidant capacity and suppressing membrane lipid peroxidation. This comprehensive coordination of ROS and membrane lipid metabolisms improved fruit resistance and delayed disease development in longans. • AEOW reduced O 2 -. burst, MDA production, and CMP rise in P. longanae -infected longan. • AEOW treatment enhanced the antioxidation capacity of P. longanae -infected longan. • AEOW treatment lowered the membrane lipid peroxidation of P. longanae -infected longan. • AEOW reduced P. longanae -induced fruit disease through enhancing antioxidant system. • AEOW reduced P. longanae -induced fruit disease by maintaining cell membrane integrity. [ABSTRACT FROM AUTHOR]

Phospholipase D plays a critical regulatory role in the pathogenicity of filamentous fungi. However, the molecular mechanism of PLD regulating the pathogenicity of filamentous fungi has not been reported. In this research, the previously constructed TrPLD1 and TrPLD2 (TrPLDs) mutants were used as test strains. Firstly, the function of TrPLDs in Trichothecium roseum was studied. Then, the effects of TrPLDs on the pathogenicity of T. roseum and the quality of the inoculated apples were verified. The results suggested that the deletion of TrPLD1 delayed the spore germination of ΔTrPLD1 and inhibited germ tube elongation by down-regulating the expressions of TrbrlA , TrabaA and TrwetA. By down-regulating the extracellular enzyme-coding gene expressions, ΔTrPLD1 inhibited the degradation of apple fruit cell wall and the change of fatty acid content during infection, reduced the cell membrane permeability and malondialdehyde (MDA) content of apple fruit, thereby maintaining the integrity of fruit cell membrane, and reduced the pathogenicity of ΔTrPLD1 to apple and kept the quality of apple. However, ΔTrPLD2 did not have a significant effect on the infection process of apple fruit by the pathogen. • The deletion of TrPLD1 inhibited the expression of genes encoding extracellular enzymes of T. roseum. • The deletion of TrPLD1 slowed down the destruction of cell membrane integrity of T. roseum during infection. • The deletion of TrPLD1 reduced the pathogenicity of T. roseum on apple fruit. [ABSTRACT FROM AUTHOR]

Sweet sorghum has strong stress resistance and is considered a promising energy crop. In the present study, the effects of salt on the membrane lipid metabolism of two sweet sorghum inbred lines (salt-tolerant M-81E and salt-sensitive Roma) were analyzed. After treatment with 150 mM NaCl, higher levels of fresh weight and chlorophyll fluorescence, as well as lower levels of malondialdehyde (MDA) were found in salt-tolerant M-81E. Concomitantly, 702 and 1339 differentially expression genes (DEGs) in M-81E and Roma were identified in response to salt stress. We determined that most DEGs were related to glycerophospholipid metabolism, glycerolipid metabolism, and other membrane lipid metabolisms. Under NaCl treatment, the expression of the membrane-associated phospholipase A1 was down-regulated at the transcriptional level, along with an increased content of phosphatidylcholine (PC) in both cultivars. The inhibition of triacylglycerol (TAG) mobilization in M-81E delayed salt-induced leaf senescence. Furthermore, enhanced levels of glycerol-3-phosphate acyltransferase (GPAT) expression contributed to improved salt resistance in M-81E. The results of this study demonstrate membrane the role of lipid regulation in mediating salt-defensive responses in sweet sorghum and expand our understanding of the relationship between changes in membrane lipid content and salt resistance. [ABSTRACT FROM AUTHOR]

Mild stress could help cells to survive more severe environmental or pathophysiological conditions. In the current study, we investigated the cellular mechanisms which contribute to the development of stress tolerance upon a prolonged (0–12 h) fever-like (40 °C) or a moderate (42.5 °C) hyperthermia in mammalian Chinese Hamster Ovary (CHO) cells. Our results indicate that mild heat triggers a distinct, dose-dependent remodeling of the cellular lipidome followed by the expression of heat shock proteins only at higher heat dosages. A significant elevation in the relative concentration of saturated membrane lipid species and specific lysophosphatidylinositol and sphingolipid species suggests prompt membrane microdomain reorganization and an overall membrane rigidification in response to the fluidizing heat in a time-dependent manner. RNAseq experiments reveal that mild heat initiates endoplasmic reticulum stress-related signaling cascades resulting in lipid rearrangement and ultimately in an elevated resistance against membrane fluidization by benzyl alcohol. To protect cells against lethal, protein-denaturing high temperatures, the classical heat shock protein response was required. The different layers of stress response elicited by different heat dosages highlight the capability of cells to utilize multiple tools to gain resistance against or to survive lethal stress conditions. [ABSTRACT FROM AUTHOR]

Browning has been the primary limitation in eggplant processing. This study investigates the molecular mechanism underlying fresh-cut eggplant fruit browning by observing the physicochemical characteristics of browning-resistant ('F') and browning-sensitive ('36′) eggplant cultivars. Browning-related enzyme activity and gene expression (PPO, LOX, and PLD) were significantly higher in the '36′ eggplant, thereby enhancing the degree of browning, compared to the 'F' eggplant. The MDA content and O2− production rate progressively increased as browning increased, while the antioxidant capacity of the fruit decreased. The cutting injury significantly activated the expression of PAL, thereby inducing the accumulation of phenolic acids, while the PPO gene was significantly upregulated, which activated the activity of polyphenol oxidase. Our results showed that the oxidation of chlorogenic acids to chlorogenic quinones resulted in the occurrence of browning, which suggests chlorogenic acid as the main browning substrate in fresh-cut eggplant. [ABSTRACT FROM AUTHOR]

The cell membrane forms a fundamental part of all living cells and participates in a variety of physiological processes, such as material exchange, stress response, cell recognition, signal transduction, cellular immunity, apoptosis, and pathogenicity. Here, we review the mechanisms and functions of the membrane structure (lipid components of the membrane and the biosynthesis of unsaturated fatty acids), membrane proteins (transmembrane proteins and proteins contributing to membrane curvature), transcriptional regulation, and cell wall components that influence the virulence and pathogenicity of filamentous fungi.

Xinjiang is the main producing area of raisins and the largest green raisins production base in China. The browning of Thompson seedless grape raisin is extremely serious during the drying process, and has become the key issue in the development of Xinjiang raisin industry. Previous studies have shown that dehydration speed has a great impact on the browning of Thompson seedless grape, but few relevant mechanisms have been studied. Here, we demonstrate the effect of dehydration speed on lipid metabolism and its relation to the browning of the Thompson seedless grape during drying. Compared to slow dehydration treatment, rapid dehydration treatment of the Thompson seedless grape exhibited a lower degree of browning and activities of lipoxygenase (LOX), a higher index of unsaturated fatty acids and degree of unsaturated fatty acid. Moreover, the Thompson seedless grape treated with rapid dehydration resulted in a lower rate of superoxide anion production, hydrogen peroxide content, membrane permeability, and malondialdehyde content. These findings demonstrate that rapid dehydration inhibiting the browning of Thompson seedless grapes might be due to the inhibiting activities of LOX and the lower accumulation of reactive oxygen species. These activities can inhibit lipid peroxidation and slow the decomposition of unsaturated fatty acid in the membrane in Thompson seedless grapes, protecting the cellular membrane structural integrity, which may result in less contact of polyphenol oxidase with phenolic substrates and less enzymatic browning during drying. The results provide a theoretical basis for the application of rapid dehydration in drying Thompson seedless grapes. [ABSTRACT FROM AUTHOR]

Cucumber fruit is very sensitive to chilling injury, which rapidly depreciates their commodity value. Herein, the effect of fucoidan treatment on cucumber under cold stress were investigated. Fucoidan treatment of cold-stored cucumber alleviated the occurrence of chilling injury, delayed weight loss, lowered electrolyte leakage and respiration rate, and retarded malondialdehyde accumulation. Different from the control fruit, fucoidan treated fruit showed a high level of fatty acid unsaturated content, fatty acid unsaturation, and unsaturation index and increased ω-FDAS activity, along with upregulated expression levels of CsSAD and CsFAD genes. Fucoidan reduced the phosphatidic acid content and membrane lipid peroxidation, lowered the phospholipase D (PLD) and lipoxygenase (LOX) activity, and downregulated the expression levels of CsPLD and CsLOX genes. Collectively, fucoidan treatment maintained the integrity of cell membrane in cold-stress cucumbers. The results provide a new prospect for the development of fucoidan as a preservative agent in the low-temperature postharvest storage of cucumbers.

Banana fruit is a widely cultivated and economically important crop, and it is susceptible to mechanical damage. The effects of three different phospholipase D inhibitors (0.1% n-butanol, 0.05% 2-butanol, and 0.1% hexanal) on the cell membrane integrity and membrane lipid metabolism in wounding banana fruits during storage were investigated. The results indicated that wounded banana treated with phospholipase D inhibitors showed significant (p < 0.05) delay in the ripening and senescence process than the control group after a 9-day storage. Of the three PLD inhibitors, hexanal showed the best effect in maintaining firmness, suppressing the increase of total soluble solids (TSS) and respiration rate, and reducing malondialdehyde (MDA) content and cell membrane permeability of wounded banana fruits. Furthermore, hexanal more efficiently decreased the phospholipase D (PLD) and lipoxygenase (LOX) activities, lowered the contents of phosphatidic acid (PA) and diacylglycerol (DAG), and inhibited the reduction of phosphatidylcholine (PC) and phosphatidylinositol (PI) after 6 days of storage, compared to n-butanol or 2-butanol. These results demonstrate that application of hexanal treatment may be a reliable method to delay the senescence of harvested bananas subjected to mechanical wounding.

1‐MCP is an ethylene inhibitor which can delay the ripening and senescence of fruits and vegetables effectively. Pteridium aquilinum var. Latiusculum (PA) is one of the wild vegetables which is famous and nutrient in China. However, the mechanism of PA preservation treated with 1‐MCP has not been reported. Consequently, the effects of postharvest 1‐MCP treatment on the changes in quality, energy metabolism, and membrane lipid metabolism of PA were investigated in this study. The results indicated that 1‐MCP treatment could effectively inhibit the decreases in firmness, titratable acid (TA) content and the increases in weight loss rate, malondialdehyde (MDA) content, membrane permeability, and membrane lipid metabolism‐related enzymes in PA. The cellular energy charge (EC) and the levels of ATP, ATP/ADP, and ATP/AMP, the activities of energy metabolism‐related enzymes, NAD+, and NADH were maintained, and the decreases in unsaturated fatty acids and the ratio of unsaturated‐to‐saturated fatty acids in the membrane of PA cells were effectively retarded by 1‐MCP treatment. A positive correlation was observed between cellular ATP levels and the ratio of unsaturated‐to‐saturated fatty acids, while negative correlations were observed between the ratio of unsaturated‐to‐saturated fatty acids and both lipid peroxidation and membrane permeability. These results indicated that higher levels of energy status, unsaturated‐to‐saturated fatty acid ratios, and lipid metabolism in the membrane could preserve the membrane integrity of postharvest PA and effectively extend its shelf life. [ABSTRACT FROM AUTHOR]

L-phenylalanine (L-Phe) is an aromatic essential amino acid. Although postharvest L-Phe treatment can alleviate chilling injury (CI) of fruit by scavenging excessive reactive oxygen species (ROS), there are no reports on whether L-Phe spraying during fruit development affects the CI of harvested muskmelon by regulating membrane lipid metabolism. In this study, plants and fruit of muskmelon (cv. Manao) were sequentially sprayed with 8 mM L-Phe four times at the young fruit stage, early expansion stage, late expansion stage and mature stage. The effect of L-Phe spraying during fruit development on CI of harvested muskmelon fruit was studied and to the related mechanism of membrane lipid metabolism was investigated. The results showed that L-Phe sprays activated phospholipase A 2 (PLA 2) and increased the content of unsaturated fatty acids such as linoleic acid, linolenic acid and oleic acid, and improved the double bond index of unsaturated fatty acids (DBI) in harvested muskmelons during cold storage. L-Phe sprays inhibited the phospholipase C (PLC) and phospholipase D (PLD), increased the content of phosphatidylinositol (PI) and phosphatidylcholine (PC), but decreased the content of phosphatidic acid (PA) in harvested muskmelons during cold storage. In addition, L-Phe sprays inhibited lipoxygenase (LOX), reduced malondialdehyde (MDA) levels and cell membrane permeability, and effectively reduced the CI index of harvested muskmelons during cold storage. Taken together, L-Phe sprays during fruit development alleviated CI in harvested muskmelons by regulating membrane lipid metabolism. • L-Phe sprays during fruit development reduced CI in harvested muskmelons. • L-Phe sprays increased the content of unsaturated fatty acids by activating PLA 2. • L-Phe sprays increased PI and PC levels by inhibiting the PLC and PLD. • L-Phe sprays maintained cell membrane integrity in muskmelons during cold storage. [ABSTRACT FROM AUTHOR]

The quality deterioration of sweetpotatoes easily during postharvest storage owing to their high respiration rate and accumulation of reactive oxygen species (ROS). In this study, an edible coating (MCW) assembled using montmorillonite, chitosan, and whey protein isolate was fabricated to improve the postharvest quality of sweetpotatoes, and the regulatory mechanism of the edible coating treatment on sweetpotato quality has investigated. The results confirmed that edible coating treatment had a positive effect on maintaining the appearance, firmness, colour, and sensory quality of sweetpotatoes, especially in maintaining free water, starch and soluble protein content, inhibiting respiration rate and delaying weight loss of sweetpotatoes stored at 25 °C for 30 d. Meanwhile, this study illuminated the MCW coating regulates ROS metabolism by upregulating superoxide dismutase, ascorbate peroxidase, and glutathione reductase gene expression, resulting in lower O 2 −. content in postharvest sweetpotato. Furthermore, the relative expression of the genes encoding lipoxygenase, phospholipase C, and phospholipase D was downregulated by the edible coating treatment and contributed to lower enzyme activity, electrolyte leakage and malondialdehyde content, which further reduced the degree of membrane lipid peroxidation and effectively maintained the structure of plasma membrane and then protected the cell integrity of sweetpotato. Collectively, this study provides useful information at the transcriptional level that MCW coating can enhance the post-harvest quality of sweetpotatoes by regulating ROS and membrane lipid metabolism. [Display omitted] • An edible coating was developed to preserve the quality of sweetpotatoes. • MCW edible coating was relatively stable and capable of dispersion. • MCW coating improved postharvest quality of sweetpotatoes stored. • MCW coating has effectively regulated ROS and membrane lipid metabolism. [ABSTRACT FROM AUTHOR]

Methyl jasmonate (MeJA) is an important bioactive metabolite in fruits and vegetables that regulates various physiological processes. The effects of MeJA on pericarp browning in longan fruit and its underlying mechanism were investigated. Results showed that treatment with 100 μM MeJA substantially suppressed the development of pericarp browning in harvested longan fruit. Compared to untreated fruit, MeJA-treated fruit exhibited reduced cell membrane permeability during storage. Meanwhile, MeJA-treated fruit displayed lower levels of phosphatidic acid and higher content of phosphatidylcholine, phosphatidylinositol, phosphatidylglycerol, and phosphatidylethanolamine through suppressing the activities of key enzymes involved in membrane lipids metabolism, such as phospholipases, lipase and lipoxygenase. Furthermore, MeJA treatment enhances the energy status of the fruit, evidenced by elevated the levels of adenosine triphosphate and energy charge. This effect could be attributed to the enhanced activities of various energy metabolism enzymes. Overall, all results suggest that MeJA is a promising agent for inhibiting pericarp browning in longan fruit through modulation of membrane lipid and energy metabolisms. • Methyl jasmonate (MeJA) inhibits pericarp browning in longan fruit during storage. • MeJA treatment prevents the accumulation of phosphatidic acid in longan fruit. • MeJA treatment reduces the activity of enzymes involved in membrane lipid metabolism. • MeJA treatment maintains a higher energy status in longan fruit during storage. • MeJA treatment enhances the activities of energy metabolism enzymes in longan fruit. [ABSTRACT FROM AUTHOR]

Sweet sorghum has strong stress resistance and is considered a promising energy crop. In the present study, the effects of salt on the membrane lipid metabolism of two sweet sorghum inbred lines (salt-tolerant M-81E and salt-sensitive Roma) were analyzed. After treatment with 150 mM NaCl, higher levels of fresh weight and chlorophyll fluorescence, as well as lower levels of malondialdehyde (MDA) were found in salt-tolerant M-81E. Concomitantly, 702 and 1339 differentially expression genes (DEGs) in M-81E and Roma were identified in response to salt stress. We determined that most DEGs were related to glycerophospholipid metabolism, glycerolipid metabolism, and other membrane lipid metabolisms. Under NaCl treatment, the expression of the membrane-associated phospholipase A1 was down-regulated at the transcriptional level, along with an increased content of phosphatidylcholine (PC) in both cultivars. The inhibition of triacylglycerol (TAG) mobilization in M-81E delayed salt-induced leaf senescence. Furthermore, enhanced levels of glycerol-3-phosphate acyltransferase (GPAT) expression contributed to improved salt resistance in M-81E. The results of this study demonstrate membrane the role of lipid regulation in mediating salt-defensive responses in sweet sorghum and expand our understanding of the relationship between changes in membrane lipid content and salt resistance.

Mild stress could help cells to survive more severe environmental or pathophysiological conditions. In the current study, we investigated the cellular mechanisms which contribute to the development of stress tolerance upon a prolonged (0–12 h) fever-like (40 °C) or a moderate (42.5 °C) hyperthermia in mammalian Chinese Hamster Ovary (CHO) cells. Our results indicate that mild heat triggers a distinct, dose-dependent remodeling of the cellular lipidome followed by the expression of heat shock proteins only at higher heat dosages. A significant elevation in the relative concentration of saturated membrane lipid species and specific lysophosphatidylinositol and sphingolipid species suggests prompt membrane microdomain reorganization and an overall membrane rigidification in response to the fluidizing heat in a time-dependent manner. RNAseq experiments reveal that mild heat initiates endoplasmic reticulum stress-related signaling cascades resulting in lipid rearrangement and ultimately in an elevated resistance against membrane fluidization by benzyl alcohol. To protect cells against lethal, protein-denaturing high temperatures, the classical heat shock protein response was required. The different layers of stress response elicited by different heat dosages highlight the capability of cells to utilize multiple tools to gain resistance against or to survive lethal stress conditions.

Browning has been the primary limitation in eggplant processing. This study investigates the molecular mechanism underlying fresh-cut eggplant fruit browning by observing the physicochemical characteristics of browning-resistant (‘F’) and browning-sensitive (‘36′) eggplant cultivars. Browning-related enzyme activity and gene expression (PPO, LOX, and PLD) were significantly higher in the ‘36′ eggplant, thereby enhancing the degree of browning, compared to the ‘F’ eggplant. The MDA content and O2− production rate progressively increased as browning increased, while the antioxidant capacity of the fruit decreased. The cutting injury significantly activated the expression of PAL, thereby inducing the accumulation of phenolic acids, while the PPO gene was significantly upregulated, which activated the activity of polyphenol oxidase. Our results showed that the oxidation of chlorogenic acids to chlorogenic quinones resulted in the occurrence of browning, which suggests chlorogenic acid as the main browning substrate in fresh-cut eggplant.

The lack of ability to control post-ripening softening is a bottleneck that affects the economic efficiency of 'Cuixiang' kiwifruit. This study investigated the softening mechanisms of fruit texture and microstructural changes during post-ripening at room temperature and established a kinetic model to predict and validate shelf life. The starch content of 'Cuixiang' decreased, total soluble solid (TSS) and sugar–acid ratio (SAR) increased, and the texture gradually became softer during post-ripening. Microstructural changes reflected starch fragmentation and disintegration, cell structure collapse, plasmolysis, and intensified mitochondrial vacuolization and cell-wall degradation during post-ripening. Changes in cell wall polysaccharide fractions and the evolution of cell membrane lipid metabolism indicated that post-ripening was accompanied by cellulose and hemicellulose degradation. In addition, pectin components transformed into water-soluble pectin, and oxidative stress across the cell membrane caused membrane damage and rupture, increasing membrane permeability. A zero-order kinetic model of firmness was selected to accurately and reliably predict the shelf life of 'Cuixiang' kiwifruit. • Ultrastructural changes of the pulp tissue were characterized by SEM and TEM. • Starch degradation led to loss of cell turgor pressure and reduced fruit hardness. • Cell wall degradation and aggravated membrane lipid metabolism led to fruit softening. • Zero-order kinetic model of firmness exactly predicted the shelf life of 'Cuixiang'. • Lay a theoretical foundation for controllable postharvest softening of 'Cuixiang'. [ABSTRACT FROM AUTHOR]

Early sowing has been extensively used in high-latitude areas to avoid drought stress during sowing; however, cold damage has become the key limiting factor of early sowing. To relieve cold stress, plants develop a series of physiological and biochemical changes and sophisticated molecular regulatory mechanisms. The biomembrane is the barrier that protects cells from injury as well as the primary place for sensing cold signals. Chilling tolerance is closely related to the composition, structure, and metabolic process of membrane lipids. This review focuses on membrane lipid metabolism and its molecular mechanism, as well as lipid signal transduction in peanut (Arachis hypogaea L.) under cold stress to build a foundation for explicating lipid metabolism regulation patterns and physiological and molecular response mechanisms during cold stress and to promote the genetic improvement of peanut cold tolerance.

Background: Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cell carcinoma and is characterized by a dysregulation of changes in cellular metabolism. Altered lipid metabolism contributes to ccRCC progression and malignancy. Method: Associations among survival potential and each gene ontology (GO) term were analyzed by univariate Cox regression. The results revealed that membrane lipid metabolism had the greatest hazard ratio (HR). Weighted gene co-expression network analysis (WGCNA) was applied to determine the key genes associated with membrane lipid metabolism. Consensus clustering was used to identify novel molecular subtypes based on the key genes. LASSO Cox regression was performed to build a membrane lipid metabolism–based signature. The random forest algorithm was applied to find the most important mutations associated with membrane lipid metabolism. Decision trees and nomograms were constructed to quantify risks for individual patients. Result: Membrane lipid metabolism stratified ccRCC patients into high- and low-risk groups. Key genes were identified by WGCNA. Membrane lipid metabolism–based signatures exhibited higher prediction efficiency than other clinicopathological traits in both whole cohort and subgroup analyses. The random forest algorithm revealed high associations among the membrane lipid metabolism–based signature and BAP1, PBRM1 and VHL mutations. Decision trees and nomograms indicated high efficiency for risk stratification. Conclusion: Our study might contribute to the optimization of risk stratification for survival and personalized management of ccRCC patients. [ABSTRACT FROM AUTHOR]

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Early sowing has been extensively used in high-latitude areas to avoid drought stress during sowing; however, cold damage has become the key limiting factor of early sowing. To relieve cold stress, plants develop a series of physiological and biochemical changes and sophisticated molecular regulatory mechanisms. The biomembrane is the barrier that protects cells from injury as well as the primary place for sensing cold signals. Chilling tolerance is closely related to the composition, structure, and metabolic process of membrane lipids. This review focuses on membrane lipid metabolism and its molecular mechanism, as well as lipid signal transduction in peanut (Arachis hypogaea L.) under cold stress to build a foundation for explicating lipid metabolism regulation patterns and physiological and molecular response mechanisms during cold stress and to promote the genetic improvement of peanut cold tolerance. [ABSTRACT FROM AUTHOR]

Chitooligosaccharide (COS), a degradation product of chitosan, can reduce chilling injury (CI) in postharvest fruit by increasing antioxidant enzyme activity. However, whether preharvest COS spray alleviates CI in muskmelon fruit after harvest by regulating membrane lipid metabolism and increasing antioxidant enzyme activity has not been reported. In this study, muskmelon plants and fruit were sprayed with 2 mL L−1 of COS at four developmental stages: young fruit, early enlargement, late enlargement, and mature stage. The expression of key genes involved in membrane lipid metabolism, fatty acid content, phospholipid component content and antioxidant enzyme activity in muskmelon fruit were measured, and the CI symptoms and index of the fruit were observed during cold storage. The results illustrated that the preharvest COS spray up-regulated the expression of CmPLA 2 , promoted the release of unsaturated fatty acids, and increased the value of the double bond index (DBI). However, the spray down-regulated the expression of CmPLC and CmPLD , increased the levels of phosphatidylcholine (PC) and phosphatidylinositol (PI), and decreased the levels of phosphatidic acid (PA). COS spray increased superoxide dismutase (SOD) and catalase (CAT) activity, decreased O 2 -· and H 2 O 2 levels, maintained cell membrane permeability, and decreased MDA levels in fruit during chilling. In addition, the spray reduced peroxidase (POD) activity and alleviated fruit pericarp browning during cold storage. Taken together, preharvest COS spray alleviated CI in muskmelon fruit by stimulating membrane lipid metabolism and improving the activities of antioxidant enzymes. • Chitooligosaccharide (COS) spray reduced chilling injury in harvested muskmelons. • COS activated membrane lipid metabolism in muskmelons during cold storage. • COS increased antioxidant enzyme activities and reduced ROS levels. • COS maintained cell membrane integrity in muskmelons during cold storage. [ABSTRACT FROM AUTHOR]

• DNP accelerated the breakdown development in the pulp of P. longanae -infected longan. • DNP raised membrane lipid-degrading enzymes activities in P. longanae -infected longan. • DNP promoted the degradation of pulp PC, PI, and UFSAs in P. longanae -infected longan. • DNP accelerated the damage of pulp membrane structure in P. longanae -infected longan. • ATP reduced P. longanae -induced pulp breakdown by lowering membrane lipid metabolism. This study aimed to illustrate how DNP and ATP affected the pulp breakdown occurrence in P. longanae -infected longan and their relationship with the membrane lipid metabolism. Compared with P. longanae -inoculated samples, the pulp of DNP-treated P. longanae -infected longan exhibited higher cellular membrane permeability, breakdown index, activities of PI-PLC, PLD, PC-PLC, LOX, and lipase, and values of SFAs, PA, and DAG, while lower levels of PI, PC, USFAs, IUFA and U/S. However, the opposite findings were observed in ATP-treated P. longanae -infected longan. The data manifested that DNP-increased the pulp breakdown occurrence in P. longanae -inoculated samples was due to the elevated MLDEs activities that reduced the contents of phospholipids (PI, PC) and USFAs, disrupting the cell membrane structures. Nevertheless, ATP decreased the pulp breakdown occurrence in P. longanae -inoculated samples, which was ascribed to the reduced MLDEs activities that raised phospholipids (PI, PC) and USFAs contents, thus maintaining the cell membrane structures. [ABSTRACT FROM AUTHOR]

• HPC has a delaying effect on the production of postharvest CI in green peppers. • HPC treatment enhanced the antioxidant enzymes gene expression and reduced lipase activity. • The relative expression levels of CaNAC1 was suppressed after HPC treatment. Green bell peppers (Capsicum annuum L.) are subject to chilling harm when being stored and transported. In the current study, the effect of hydroxypropyl cellulose (HPC) on chilling injury (CI) of green peppers stored at 4 °C for 8 d and then moved to 20 °C for 3 d to simulate shelf life was examined. Results exhibited that the HPC treatment greatly reduced the CI of green pepper, decreased the degradation of chlorophyll and ascorbic acid, controlled the buildup of malondialdehyde (MDA), and decreased the level of relative conductivity, relative to untreated controls, all of which reflect a decreased level of injury. HPC increased the activities and gene expressions of antioxidant enzymes, including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX), resulting in lower levels of reactive oxygen species (ROS) in the stored peppers. The major enzymes involved in membrane lipid metabolism were controlled by HPC, which also regulated their gene expressions. These findings demonstrate that the use of HPC on harvested green peppers is a viable strategy for enhancing their tolerance to chilling temperatures and functions through its ability to activate the antioxidant system in green pepper and modify membrane lipid metabolism. [ABSTRACT FROM AUTHOR]

• CA-g-CS/PLA regulates essential genes to maintain the quality of A. bisporus. • CA-g-CS/PLA retards cell membrane damage and elongation in A. bisporus. • CA-g-CS/PLA promotes the activation of MAPK signalling pathway in A. bisporus. In this study, the self-developed caffeic acid-grafted-chitosan/polylactic acid (CA-g-CS/PLA) film was applied to the preservation of Agaricus bisporus , and the potential mechanism of retarding its quality loss through regulation of essential genes was further explored. The results of transcriptome analysis showed that CA-g-CS/PLA packaging could regulate essential genes involved in membrane lipid metabolism and energy metabolism to delay the decrease in unsaturated fatty acids, energy loss and reactive oxygen species (ROS) accumulation by decreasing the respiration rate of A. bisporus. In addition, the expression of SHO1 and wis1 related to mitogen-activated protein kinase (MAPK) signalling in the CA-g-CS/PLA group of A. bisporus was increased, which indicated that the osmotic balance could be better maintained. Therefore, CA-g-CS/PLA packaging could improve the quality of postharvest A. bisporus by regulating the essential genes related to the pathway of membrane lipid metabolism, energy and ROS metabolism, and MAPK signalling transduction. [Display omitted] [ABSTRACT FROM AUTHOR]

Cold storage is the primary postharvest technology used to maintain fruit quality and is generally employed to prolong the storage life of ‘Nanguo’ pears ( Pyrus ussuriensis Maxim). However, pericarp browning gradually appeared when ‘Nanguo’ pears were kept at 20 °C after storage for 120 and 180 d at 0 °C. In this study, changes in the browning substrate and activity of key enzyme, membrane permeability, and the extent of membrane lipid peroxidation were investigated. Changes in the activity and gene expression of enzymes involved in the membrane lipid metabolism pathway were also studied. Significantly higher polyphenol oxidase (PPO) activity and lower total phenolic content were observed in fruit when browning occurred. Fruit kept for 180 d in cold storage showed a significant increase in membrane permeability and malondialdehyde (MDA) content compared to fruit stored for 60 and 120 d. This increase occurred late in cold storage and was maintained during subsequent shelf life. The activity of lipoxygenase (LOX) was remarkably increased and levels of PuPLD and PuLOX transcripts were markedly up-regulated during cold storage. During shelf life after cold storage, when pericarp browning occurred, the activities of phospholipase D (PLD) and LOX were significantly higher and expressions of PuPLD and PuLOX were significantly increased. These results indicated that the severity of pericarp browning during shelf life is related to the duration of cold storage. Pericarp browning resulted from membrane damage, possibly due to expression of PuPLD and PuLOX . [ABSTRACT FROM AUTHOR]

• AEW inhibited longan pulp breakdown through regulating membrane lipid metabolism. • AEW inhibited activities of PLD, lipase and LOX, and the expressions of related genes. • AEW reduced the degradations of membrane phospholipids and unsaturated fatty acids. • AEW retained structural and functional integrity of the cell membrane in longan pulp. This study investigated the effect of acidic electrolyzed water (AEW) on the inhibition of pulp breakdown of postharvest longan fruit. The harvested longan fruit were immersed in AEW (pH 2.5 and available chlorine concentration 80 mg L−1) for 10 min, then air-dried and stored at 25 °C. It was revealed that the AEW treatment reduced the cell membrane permeability and breakdown incidence of pulp by modulating membrane lipid metabolism. Compared to the untreated fruit, AEW treatment significantly suppressed the activities of lipoxygenase (LOX), lipase, and phospholipase D (PLD), down-regulated the expression of DlPLD1, DlPLD2, Dllipase1, Dllipase2, DlLOX1 and DlLOX2 , and reduced the hydrolysis of phosphatidylinositol (PI) and phosphatidylcholine (PC) and the accumulation of phosphatidic acid (PA). In addition, a lower saturated fatty acids (SFAs) proportion, but a higher unsaturated fatty acids (USFAs) proportion, the index of unsaturated fatty (IUFA), and unsaturated to saturated fatty acids ratio (U/S) were found in AEW-treated longan fruit. These findings indicated that AEW treatment inhibited the activities of membrane lipid metabolism-related enzymes (LOX, lipase, and PLD) and their expressions of associated genes, and altered the cell membrane lipid composition, which was conductive to maintaining the integrity of cell membrane, ultimately alleviating the progress of pulp breakdown in harvested longan fruit. Consequently, AEW treatment may be a reliable method to reduce the occurrence of pulp breakdown and improve the storability of harvested longan fruit. [ABSTRACT FROM AUTHOR]

Leaf yellowing has become an important limiting factor for harvested pak choi, affecting its commodity quality and market value. Our previous results showed that in stay-green pak choi, nye , an SGR mutant likely prolongs its shelf life. To uncover the mechanism of the SGR mutation underlying extended shelf life, nye and its near isogenic line (nye-) harboring the SGR allele were used to conduct the postharvest analysis. Compared with nye- , nye exhibited delayed leaf yellowing and weight loss, prolonged shelf life, and maintained high –a* value and Fv/Fm during shelf life. High chlorophyll content and integral membrane structure were observed in nye , which likely contributed to delayed postharvest yellowing. The membrane integrity of nye was well maintained, manifested as a low level of electrolyte leakage and malondialdehyde (MDA). The increased accumulation of phospholipids and glycolipids, high degree of fatty acid unsaturation, and downregulated activities and gene expression of lipoxygenase （LOX）and phospholipase D （PLD）proved that less severe membrane lipid metabolism occurred in nye. These factors may be the key to delaying postharvest yellowing and extending shelf life. Our findings will contribute to the development of a new method to delay postharvest yellowing and maintain the shelf life and commercial value of leafy vegetables by using the SGR gene. • The SGR mutation prolongs shelf life of pak choi. • Retardation of chlorophyll degradation is a critical factor for long shelf life. • Membrane lipid composition, structural integrity, function contribute to shelf life. [ABSTRACT FROM AUTHOR]

[Display omitted] • Caffeic acid grafted chitosan/polylactic acid (CA-g-CS/PLA) was used for packaging. • The Agaricus bisporus packaged by CA-g-CS/PLA showed more complete cell morphology. • CA-g-CS/PLA slowed the decline in lipid unsaturation and phospholipids. • The activities and expression of phospholipid degrading enzymes were inhibited. In this study, the film assembled by caffeic acid-grafted-chitosan/polylactic acid (CA-g-CS/PLA) was used for packaging postharvest Agaricus bisporus , and its effects on postharvest quality of Agaricus bisporus by regulating membrane lipid metabolism were investigated. The results showed that compared to traditional polyethylene packaging, the cell morphology of Agaricus bisporus packaged by CA-g-CS/PLA demonstrated a more complete structure due to its lower permeability, higher fluidity and stronger ability to maintain free water. Meanwhile, CA-g-CS/PLA packaging could effectively delay the decrease rate of unsaturation value and phospholipids of Agaricus bisporus during storage. In addition, the activities and expression levels of lipoxygenase (LOX), phospholipase C (PLC) and phospholipase D (PLD) in Agaricus bisporus packaged with CA-g-CS/PLA were inhibited, while those of glycerol-3-phosphate acyltransferase (GPAT) and sphingomyelin synthase (SMS) were promoted. Therefore, CA-g-CS/PLA packaging could enhance the postharvest quality of Agaricus bisporus by regulating membrane lipid metabolism, which has great application potential in the field of new intelligent packaging. [ABSTRACT FROM AUTHOR]

• 24-Epibrassinolide (EBR) treatment alleviates chilling injury of peach fruit. • EBR treatment enhances chilling tolerance by regulating membrane lipid metabolism. • EBR treatment upregulates the gene expression of PpCBF5. • PpCBF5 negatively regulates the transcriptions of PpPLD and PpLipase. 24-Epibrassinolide plays an important role in regulating abiotic stress, which may enhance cold resistance of fruits and vegetables. C-repeat binding factor (CBF) has a rapid response to cold stress and is a crucial transcription factor for cold signal pathway. This study investigated the potential effect of EBR treatment on membrane lipid metabolism and the possible regulation mechanism of PpCBF5 to membrane lipid metabolism in peach fruit. The results showed that EBR treatment effectively suppressed the increase in activities and gene expression of phospholipase D, lipoxygenase and lipase, inhibited the hydrolysis of phosphatidylcholine and phosphatidylinositol to pohosphatidic acid, reduced the malondialdehyde content, and enhanced unsaturated fatty acids contents, thus alleviated the membrane lipid peroxidation and maintained the stability of cell membrane. In addition, the results of molecular assays in vivo, including dual luciferase reporter assay, in vivo bioluminescence imaging, yeast one hybrid and transient overexpression assay, showed that PpCBF5 negatively regulated the transcription of PpPLD and PpLipase. In conclusion, EBR treatment enhanced chilling tolerance of peach fruit through regulating membrane lipid metabolism and PpCBF5 might act as a crucial regulatory factor on membrane lipid metabolism. [ABSTRACT FROM AUTHOR]

• Ethylene alleviates CI of banana. • Ethylene inhibits MabHLH060/183 expression. • MabHLH060/183 target the promoters of PA formation genes. Chilling injury (CI) of banana represents a serious problem constraining postharvest preservation in the industry. Application of ethylene was found to efficiently attenuate CI of banana, however, the mechanism of which remains to be investigated. Here, we found that application of ethrel could ameliorate the CI of banana, as evidenced by lower CI index, electrolytic leakage and malondialdehyde content. Meanwhile, expression of phosphatidic acid (PA) formation genes MaPLDδ1 , MaPLDδ5 and MaDGK2 , as well as two transcriptional regulators MabHLH060 and MabHLH183 was significantly increased with the progression of CI, but decreased under ethrel treatment. MabHLH060 and MabHLH183 were shown to locate in nucleus and have transactivation ability. Importantly, these two transcriptional regulators MabHLH060/183 recognized the E-box elements in the promoters of MaPLDδ1 , MaPLDδ5 and MaDGK2 , and promoted their transcription. Together, these findings suggest that ethylene-alleviated CI of banana may involve the MabHLH060/183 module in modulating the expression of PA formation genes. [ABSTRACT FROM AUTHOR]