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Programmed cell death (PCD) is a genetically regulated process of cell suicide essential for plant development. The 'malate valve' is a mechanism that ensures redox balance across different subcellular compartments. In broccoli, the BomMDH1 gene encodes malate dehydrogenase in mitochondria, a critical enzyme in the 'malate circulation' pathway. This study investigates the functional role of BomMDH1 in malate (MA)-induced apoptosis in bright yellow-2 (BY-2) suspension cells. Findings revealed that transgenic cells overexpressing BomMDH1 showed enhanced viability under MA-induced oxidative stress compared to wild-type (WT) cells. Overexpression of BomMDH1 also reduced levels of reactive oxygen species (ROS), hydrogen peroxide (H 2 O 2), and malondialdehyde (MDA), while increasing the expression of antioxidant enzyme genes such as NtAPX , NtAOX1a , NtSOD , and NtMDHAR. Additionally, treatment with salicylhydroxamic acid (SHAM), a characteristic inhibitor of mitochondrial respiration, further improved the anti-apoptotic activity of BY-2 cells. Overall, these results highlighted the function of the BomMDH1 gene and the potential of SHAM treatment in mitigating oxidative stress in BY-2 suspension cells. • Malate treatment accelerated the yellowing process of broccoli. • Overexpressing BomMDH1 in BY-2 cells exhibited stronger cell viability. • Confirmed the effective role of SHAM in BY-2 suspension cells exposed to MA. [ABSTRACT FROM AUTHOR]

Dysregulation of vascular smooth muscle cell (VSMC) function leads to a variety of diseases such as atherosclerosis and hyperplasia after injury. However, antiproliferative drug targeting VSMC exhibits poor specificity. Therefore, there is an urgent to develop highly specific antiproliferative drugs to prevention and treatment VSMC dedifferentiation associated arteriosclerosis. Kanglexin (KLX), a new anthraquinone compound designed by our team, has potential to regulate VSMC phenotype according to the physicochemical properties. This project aims to evaluate the therapeutic role of KLX in VSMC dedifferentiation and atherosclerosis, neointimal formation and illustrates the underlying molecular mechanism. In vivo, the ApoE−/− mice were fed with high-fat diet (HFD) for a duration of 13 weeks to establish the atherosclerotic model. And rat carotid artery injury model was performed to establish the neointimal formation model. In vitro, PDGF-BB was used to induce VSMC dedifferentiation. We found that KLX ameliorated the atherosclerotic progression including atherosclerotic lesion formation, lipid deposition and collagen deposition in aorta and aortic sinus in atherosclerotic mouse model. In addition, The administration of KLX effectively ameliorated neointimal formation in the carotid artery following balloon injury in SD rats. The findings derived from molecular docking and surface plasmon resonance (SPR) experiments unequivocally demonstrate that KLX had potential to bind PDGFR-β. Mechanism research work proved that KLX prevented VSMC proliferation, migration and dedifferentiation via activating the PDGFR-β-MEK -ERK-ELK-1/KLF4 signaling pathway. Collectively, we demonstrated that KLX effectively attenuated the progression of atherosclerosis in ApoE-/- mice and carotid arterial neointimal formation in SD rats by inhibiting VSMC phenotypic conversion via PDGFR-β-MEK-ERK-ELK-1/KLF4 signaling. KLX exhibits promising potential as a viable therapeutic agent for the treatment of VSMC phenotype conversion associated arteriosclerosis. [ABSTRACT FROM AUTHOR]

The contribution of CpERD and CpRAB on cold resistance of zucchini fruit under high relative humidity (HRH) storage was studied. The results showed that higher accumulations of CpRAB and CpERD were associated with decreased chilling injury in zucchini. HRH storage maintained a higher level of CpDREB1–5 expression and further activated the transcription of CpRAB and CpERD. CpRAB and CpERD exhibited protective roles in lactate dehydrogenase activity in vitro and cell activity of transformed E.coli in vivo under stresses. In addition, CpRAB and CpERD physically interacted with the CpSOD1 and CpCAT2 of zucchini. The transient expression of CpRAB and CpERD maintained higher antioxidant activities in tobacco leaves under cold stress. Taken together, the results suggested that accumulations of CpRAB and CpERD under HRH storage enhanced the chilling resistance of zucchini fruit, which may be due to their potential protective function of enzyme activities under cold and oxidative stress. • High RH maintained higher CpRAB/ERD accumulation in zucchini. • CpRAB and CpERD physically interacted with CpSOD1 and CpCAT2. • CpRAB/ERD enhanced antioxidant activities in tobacco leaves under cold stress. • CpRAB/ERD maintained LDH activities in vitro under cold and oxidative stress. • CpRAB/ERD protected cell activity of transformed E.coli model under stress. [ABSTRACT FROM AUTHOR]

To understand better the regulatory mechanism of the carotenoid accumulation, the expression profile of relevant carotenoid genes and metabolites were compared between two peach cultivars with different colors during fruit development. Meanwhile, the change pattern of carotenoid content and expression of carotenoid metabolic genes in peaches after harvest in response to blue light were also investigated. As compared to the yellow fleshed-cultivar ‘Jinli’, lower carotenoid levels were observed in skin and pulp in white peach cultivar ‘Hujing’, which might be explained by differentially expression of PpCCD4 gene. With respect to ‘Jinli’, the carotenoid accumulation during fruit development in fruit skin was partially linked with the transcriptional regulation of PpFPPS , PpGGPS , PpLCYB and PpCHYB . However, in the pulp, the accumulation might be also associated with the increased transcriptions of PpPDS , along with the above four genes. Blue light treatment induced carotenoid accumulation in ‘Jinli’ peaches during storage. In addition, the treated-fruit displayed higher expression of all the eight genes analysed with a lesser extent on PpCCD4 , which suggested that the much more increased carotenoid synthesis rate could result in the higher carotenoid content in blue light-treated fruit. The results presented herein contribute to further elucidating the regulatory mechanism of carotenoid accumulation in peach fruit. [ABSTRACT FROM AUTHOR]

The effect on hydroxyl radical ( OH) on cellular wall disassembly and aril breakdown in mulberry fruit was investigated in vitro and in vivo . The in vitro experiment showed OH induced total sugar and uronic acid released from the cell wall material of mulberries in a dose-dependent manner. Then the harvested mulberries were treated with 5 mM OH to find out its effect in vivo. The results suggested that the application of exogenous OH induced degradation of cellular wall polysaccharides, especially water soluble pectin (WSP) and hemicellulose, which was associated with the higher incidence of aril breakdown in OH-treated mulberries. Meanwhile, the results of gel permeation chromatography analysis further demonstrated that OH enhanced depolymerization and structural modifications of polysaccharides of mulberries during storage as experienced by the downshift in molecular mass of WSP and hemicellulose fractions. These results indicated that as a consequence of the enhanced degradation of cell wall polysaccharides, OH could increase the incidence of aril breakdown in harvested mulberry fruit during storage. [ABSTRACT FROM AUTHOR]

The effect of blue light exposure on sugar metabolism and cryptochrome gene expression in postharvest Chinese bayberry fruit was investigated. Results showed blue light treatment significantly increased the contents of sucrose, fructose, and glucose in bayberries during storage. Expression analysis revealed that transcripts of three sucrose phosphate synthase ( MrSPS1 , MrSPS2 , and MrSPS3 ) were markedly induced by blue light treatment throughout the storage period, but increases in expression of two acid invertase genes ( MrINV2 and MrINV3 ) were detected only at the beginning of storage. Meanwhile, a hexokinase gene ( MrHXK1 ) and two genes of cryptochrome ( MrCRY1 and MrCRY2 ) were isolated from bayberry fruit. The expression levels of MrHXK1 and MrCRY1 were up-regulated during blue light exposure only at the end of storage; however, significantly higher amounts of MrCRY2 transcripts were found in blue light exposed-fruit throughout the storage period. Results suggest that blue light treatment increases the sugar content in postharvest bayberries during storage by regulating the expression levels of genes involved in sugar metabolism. Additionally, the enhancement of transcripts of MrCRY1 and MrCRY2 might also be associated with the increase in sugar content in blue light exposed fruit. [ABSTRACT FROM AUTHOR]

The involvement of ethylene gas in the ripening of peach fruit is a symbolic phenomenon that has a place in the history of research on plant hormones. It is well documented that fruit ripening is developmentally regulated and affected by environmental factors such as temperature and light. Blue light has been shown to induce pigment synthesis in postharvest fruit. However, information on its effect on fruit ripening is still limited. This study aimed to investigate the effect of light-emitting diode blue light treatment at 40 μmol m −2 s −1 on fruit ripening, ethylene biosynthesis and signalling in postharvest peaches during storage at 10 °C. Blue light exposure induced fruit ripening as expressed by the enhanced decline of fruit firmness and increases in skin colour parameters, which was associated with the increase in ethylene production because of the up-regulated expression of PpLOXs and ethylene biosynthetic genes such as PpACO1 and PpACS3 . Meanwhile, six genes in relation to ethylene perception and signalling were also investigated using real-time PCR. Among them, blue light treatment significantly inhibited expression of PpERS1 and enhanced transcript levels of PpEIN2 , PpEIL1, PpEIL2 and PpERF2 , which led to an induction ethylene signalling pathway and resulted in turn into the promotion of ethylene production and fruit softening in postharvest peaches. Compared to control fruit stored at darkness, higher expression level of ethylene biosynthetic and signalling genes in blue light exposed peaches could be beneficial for its ethylene production and consequently fruit ripening. [ABSTRACT FROM AUTHOR]

Blueberries are now the second most economically important soft fruit. However, they are highly perishable and susceptible to rapid spoilage. One of the main factors limiting postharvest life of blueberries is softening. The changes of fruit firmness, cell wall degrading enzymes and cell wall composition of ‘Brilliant’ blueberry ( Vaccinium ashei cv. Brilliant) were investigated in this study. The results showed fruit firmness declined concomitantly with the increase of the content of water soluble pectin (WSP) during storage paralleled by a decreasing amount of sodium carbonate soluble pectin (SSP), cellulose and hemicellulose. Blueberries stored at low temperature (5 °C) maintained higher fruit firmness than those stored at 10 °C, which was due to the lower WSP content and higher contents of SSP, cellulose and hemicellulose. Meanwhile, the lower activities of cell wall degrading enzymes such as polygalacturonase, cellulase, β-galactosidase and α-mannosidase in blueberries at 5 °C were associated with greater fruit firmness and lower WSP content as compared to those in fruit stored at 10 °C. [ABSTRACT FROM AUTHOR]

The effect of ethanol treatment on disease resistance against anthracnose rot in postharvest loquat fruit and its possible mechanism were investigated. Our data implied that treatment of loquat fruit with ethanol at 300 μl/l significantly inhibited the anthracnose rot caused by Colletotrichum acutatum and maintained the overall quality. Ethanol treatment suppressed activities of catalase and ascorbate peroxidase while increased superoxide dismutase activity in C. acutatum -inoculated loquat fruit, thus resulting in a higher level of H 2 O 2 , which might serve as a crucial role to activate disease resistance. Meanwhile, the activities of defense-related enzymes including phenylalanine ammonia-lyase, peroxidase, polyphenol oxidase, chitinase and β-1,3-glucanase were significantly enhanced by the ethanol treatment. In addition, 300 μl/l ethanol exhibited an effective antifungal activity against spore germination and mycelial growth of C. acutatum in vitro . Therefore, these results suggest that ethanol can inhibit anthracnose rot in postharvest loquat fruit, possibly via inhibiting pathogen growth directly and inducing disease resistance indirectly. [ABSTRACT FROM AUTHOR]

Effect of blue light-emitting diode light (470 nm) treatment on anthocyanin accumulation and expression of related genes in Chinese bayberry fruit was investigated. Bayberries hand-harvested when nearly 3/4 of the fruit turned red were exposed to blue light for 8 days at 10 °C. Anthocyanin accumulated in bayberries during storage, which can be drastically enhanced by blue light treatment. The blue light treatment also increased the expression of MrMYB1 and structural genes involved in anthocyanin biosynthesis such as MrCHI , MrF3H , MrF3′H , MrDFR1 , MrDFR2 and MrANS . These findings suggested that the induction of anthocyanin accumulation by blue light was associated with the increased expression of anthocyanin biosynthetic and regulatory genes. Our results suggested that blue light treatment may be a useful technique to enhance commercial and nutritional value of Chinese bayberry fruit. [ABSTRACT FROM AUTHOR]

Highlights: [•] ‘Qingzhong’ fruit experienced stronger disease resistance than ‘Fuyang’. [•] ‘Qingzhong’ fruit showed higher activities of antioxidant enzymes. [•] The resistant cultivar manifested higher contents of linolenic and linoleic acids. [•] Loquat disease resistance was due to antioxidant system and unsaturated fatty acids. [Copyright &y& Elsevier]

High relative humidity (RH) cold room (RH: 98 ± 2%) controlled by a 'dry fog' system and normal cold room (RH: 74 ± 2%) were used to store zucchini fruit to investigate the regulation of high RH on chilling tolerance and sugar and ethanol metabolisms under cold stress. High RH storage inhibited chilling injury (CI) and maintained higher activities of sucrose synthase-synthesis and sucrose phosphate synthase and contents of glucose, fructose and sucrose in zucchini fruit. Meanwhile, high RH-stored fruit exhibited lower activities of hexokinase, phosphofructokinase, and pyruvate kinase as compared with the control. Besides, the accumulation of acetaldehyde and ethanol under cold stress was decreased by high RH storage together with the inhibition of the increase in activities of alcohol dehydrogenase, pyruvate decarboxylase and expressions of related genes. Taken together, high RH storage enhanced chilling tolerance in zucchini fruit by maintaining high levels of soluble sugars and inhibiting ethanol production. • Zucchini fruit stored under high RH showed increased chilling tolerance. • High RH storage maintained higher levels of soluble sugars in zucchini fruit. • High RH storage regulated the activities of enzymes related to glycolysis. • High RH storage inhibited the ethanol fermentation in zucchini fruit. [ABSTRACT FROM AUTHOR]

Highlights: [•] UV-C treatment delayed senescence in postharvest peach fruit. [•] UV-C decreased respiratory activity by inhibiting SDH and CCO activities. [•] UV-C treated fruit manifested better integrity of mitochondrial membrane. [•] Decreased respiratory activity by UV-C was attributed to senescence retardation. [•] The delay of senescence by UV-C was also due to the increased mitochondrial membrane integrity. [ABSTRACT FROM AUTHOR]

Highlights: [•] MeJA treatment induced disease resistance in postharvest loquat fruit. [•] MeJA treated fruit manifested higher contents of polyamines. [•] MeJA maintained higher levels of ATP. [•] MeJA induced disease resistance due to the increased polyamines and ATP. [ABSTRACT FROM AUTHOR]

Abstract: The relationship between chilling injury and sugar metabolism was investigated in loquat fruit stored at 1°C for 35days. No symptoms of chilling injury occurred in the fruit, of ‘Ninghaibai’ cultivar, during the whole storage whereas, in ‘Dahongpao’ fruit, severe chilling symptoms were observed after 20days of storage at 1°C. ‘Ninghaibai’ fruit had higher levels of glucose and fructose and higher activities of sucrose hydrolyzing enzymes, such as sucrose synthase-cleavage and invertase, than had ‘Dahongpao’. Furthermore, the chilling resistant ‘Ninghaibai’ fruit also showed higher activities of hexokinase and fructokinase, involved in hexose phoshorylation and sugar signal generation. These results suggest that the higher content of hexoses and activities of hexose sensors were likely part of the mechanism for chilling tolerance of loquat fruit. [Copyright &y& Elsevier]

Abstract: The effect of elicitors associated with host defence on betacyanin accumulation in Amaranthus mangostanus seedlings was investigated. Under the conditions of the experiments, betacyanin accumulation was generally enhanced by light. Methyl jasmonate (MeJA) treatment increased betacyanin synthesis in a concentration-dependent response. Seedlings treated with ethylene as 5mM Ethephon also had elevated levels of betacyanin. In contrast, salicylic acid (SA) and H2O2 treatments had no influence on betacyanin contents in light or dark. Combined MeJA with Ethephon or H2O2 had an additive effect on betacyanin accumulation in dark-grown seedlings. However, a decline was recorded in light-grown seedlings. Moreover, an antagonistic effect on betacyanin synthesis was found when MeJA and SA were added simultaneously. Our results indicate that betacyanin content in A. mangostanus seedlings can be upregulated by MeJA and ethylene. Both additive and antagonistic effects in regulating betacyanin synthesis in A. mangostanus seedlings were observed between MeJA and other elicitors. [Copyright &y& Elsevier]

Abstract: Loquat fruit were pretreated with 10μmoll−1 methyl jasmonate (MeJA) for 24h at 20°C and then stored at 1°C for 35days to investigate the effect of MeJA treatment on chilling injury (CI) and changes in the contents of proline and γ-aminobutyric acid (GABA). The control fruit exhibited severe flesh leatheriness, a specific CI symptom, after 21days of storage at 1°C, but it was reduced in MeJA-treated fruit. During the development of CI in fruit, proline and GABA accumulated with the storage time, while MeJA treatment enhanced the increases in proline and GABA contents. The MeJA-treated fruit exhibited higher activities of Δ1-pyrroline-5-carboxylate synthetase (P5CS), ornithine δ-aminotransferase (OAT) and glutamate decarboxylase (GAD), and lower proline dehydrogenase (PDH) activity than control during storage. These results suggest that the reduction in CI in loquat fruit by MeJA may be due to the increased proline and GABA contents. [Copyright &y& Elsevier]

Abstract: The effect of 1-methylcyclopropene (1-MCP) on senescence and quality maintenance of green bell pepper fruit was investigated. To explore the optimum concentration of 1-MCP to delay senescence, pepper fruit were treated with 0.5, 1.0 or 1.5μLL−1 1-MCP and then stored for 10d at 20°C. The results showed that the application of 1-MCP at 1.0μLL−1 was most effective in delaying senescence, manifested as chlorophyll degradation and increase in weight loss. 1-MCP treated peppers had higher levels of chlorophyll, protein and vitamin C and lower respiration rates and ethylene production compared with that in control peppers. In addition, 1-MCP enhanced activities of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase and levels of polyamines including putrescine, spermidine and spermine. These results suggested that the delaying senescence of green bell pepper by 1-MCP treatment is associated with enhanced antioxidant enzyme activities and polyamine contents. [Copyright &y& Elsevier]

Abstract: Peach fruit were immersed in 5mM γ-aminobutyric acid (GABA) solution for 10min at 20°C and then stored at 1°C for 5weeks to investigate the effect of GABA treatment on chilling injury (CI), antioxidant enzymes and energy status in peach fruit. The results showed that GABA treatment significantly inhibited CI incidence of peaches and enhanced activities of antioxidant enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase, glutathione peroxidase, glutathione S-transferase, monodehydroascorbate reductase and dehydroascorbate reductase. The treatment also increased contents of adenosine triphosphate and adenosine diphosphate, but lowered adenosine monophosphate content, which resulted in a higher level of energy charge in treated fruit. These results indicated that GABA increased chilling tolerance of peach fruit through enhancing its enzymatic antioxidant system and maintaining energy status in peach fruit. [Copyright &y& Elsevier]

Abstract: Two cultivars of loquat fruit with contrasting chilling resistance were stored at 1°C for 35days to investigate the relationship between chilling injury and fatty acid composition and its antioxidant system. No symptoms of chilling injury occurred in the fruit of ‘Qingzhong’ cultivar during the whole storage, whereas in ‘Fuyang’ fruit, chilling injury increased sharply after 21days of storage at 1°C. ‘Qingzhong’ fruit had lower levels of superoxide radical and H2O2, in addition to lower lipoxygenase activity, but higher membrane lipid unsaturation and higher activities of superoxide dismutase and catalase than ‘Fuyang’. Furthermore, the chilling resistant ‘Qingzhong’ fruit also showed higher activities of antioxidant enzymes involved in ascorbate–glutathione cycle and higher levels of ascorbate acid and reduced glutathione. These results suggest that the higher membrane lipid unsaturation and the more efficient antioxidant system were both beneficial in enhancing resistance of loquat fruit to chilling injury. [Copyright &y& Elsevier]

Abstract: The effect of ultrasound (40kHz, 10min) and salicylic acid (SA, 0.05mM) either separately, or combined on blue mold caused by Penicillium expansum in peach fruit was investigated. The results showed that the application of SA alone could reduce blue mold, while the use of ultrasound had no effect. Our results also revealed that SA combined with ultrasound treatment was more effective in inhibiting fungal decay during storage than the SA treatment alone. The combined treatment increased the activities of defense enzymes such as chitinase, β-1,3-glucanase, phenylalanine ammonia-lyase, polyphenol oxidase and peroxidase, which were associated with higher disease resistance induced by the combined treatment. Furthermore, the combined treatment did not impair the quality parameters of peach fruit after 6days of storage at 20°C. These results suggested that the combination of ultrasound and SA treatment may be a useful technique to reduce blue mold in peach fruit. Industrial relevance: This paper investigates the effect of ultrasound combined with SA on decay incidence of peach fruit. The results presented demonstrate that the effect of the combined treatment on the disease resistance and fruit quality should be considered by processors prior to its adoption as a preservation technique. [Copyright &y& Elsevier]

Abstract: The effects of Chinese bayberry fruit extract (CBFE) ingestion on hepatic and colonic oxidative stress and 1,2-dimethylhydrazine (DMH)-induced intestinal aberrant crypt foci (ACF) development in rats were investigated. Rats were administered DMH (35mg/kg body weight) and were supplemented with CBFE (50 or 500mg/kg body weight every day) for 16weeks. Results showed that DMH consumption induced intestinal ACF development and adenoma or adenocarcinoma formation, which were significantly reduced with CBFE supplement. The CBFE treatments increased reduced glutathione levels and activities of superoxide dismutase, catalase and glutathione reductase, in both hepatic and colonic tissues; however, the activities of glutathione-S-transferase and glutathione peroxidase were inhibited. These results indicate that CBFE, rich in phenolic compounds, effectively inhibits DMH-induced ACF and colonic tumour development by alleviating oxidative stress. [ABSTRACT FROM AUTHOR]

Abstract: The effect of benzo-thiadiazole-7-carbothioic acid S-methyl ester (BTH), at 0.2g/l, on antioxidant enzymes, radical-scavenging activity and decay development in strawberry (Fragaria×ananassa Duch.) fruit, was investigated. The results showed that BTH treatment enhanced the activities of antioxidant enzymes, including superoxide dismutase, ascorbate peroxidase, and glutathione reductase. The treatment increased the contents of phenolic and anthocyanin in strawberry fruit, as well as radical-scavenging capacity, expressed as 1,1-diphenyl-2-picrylhydrazyl and superoxide radical values and reducing power. The treatment also decreased the development of decay compared to control fruit. These results indicated that BTH might increase the disease resistance of strawberry fruits by enhancing their antioxidant systems and their free radical-scavenging capabilities. [ABSTRACT FROM AUTHOR]

Abstract: The feasibility of 0.2gl−1 benzo-thiadiazole-7-carbothioic acid S-methyl ester (BTH) to improve the efficacy of Pichia membranefaciens in controlling postharvest blue mould decay in peach fruit was investigated. Our results showed that biocontrol activity of P. membranefaciens against blue mould caused by Penicillium expansum in peach fruit could be enhanced by addition of 0.2gl−1 BTH. The combination of P. membranefaciens and BTH resulted in a more effective control of blue mould than individual treatment of P. membranefaciens or BTH alone. The combined treatment had a synergistic effect on the induction of superoxide dismutase, catalase, ascorbate peroxidase, chitinase and β-1,3-glucanase activities, which induced stronger disease resistance in fruit than BTH or yeast alone, and resulted in a lower lesion diameter and disease incidence of blue mould decay in peaches. Furthermore, the combined treatment did not impair the quality parameters including fruit firmness and contents of total soluble solids, titratable acidity and vitamin C of peach fruit after 6days of storage at 20°C. These results suggested that the use of BTH may be an effective method to improve the biological activity of P. membranefaciens. [Copyright &y& Elsevier]

Abstract: The effect of heat treatment (38°C, 12h in air) and salicylic acid (SA, 1mM) either separately or combined, on internal browning (IB) in cold-stored peach fruit (Prunus persica Batsch) was investigated. The results showed that heat combined with SA treatment was the most effective method of alleviating IB in peach fruit during cold storage at 0°C. The activities of antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were significantly induced, while lipoxygenase activity was decreased by heat combined with an SA treatment. In addition, the combined treatment increased the levels of polyamines including putrescine, spermidine and spermine. These results suggest that the combination of heat and SA treatment may be a useful technique to alleviate IB in cold-stored peach fruit and the reduction in IB by the combined treatment may be due to the induction of antioxidant enzymes and increase in polyamine levels. [ABSTRACT FROM AUTHOR]

Abstract: The potential enhancement of Pichia membranifaciens by ammonium molybdate (NH4Mo) to control blue mould caused by Penicillium expansum on peach fruit was investigated. Combining P. membranifaciens at 1×108 cell/ml with 1mM NH4Mo provided a more effective control of blue mould rot than applying the yeast or NH4Mo alone. Addition of 1mM NH4Mo significantly increased the growth of P. membranifaciens in peach wounds, but did not affect the population in nutrient yeast dextrose broth medium. The in vitro experiment showed that the combined treatment inhibited spore germination and germ tube elongation of P. expansum in comparison with the treatment of P. membranifaciens or NH4Mo alone. Moreover, P. membranifaciens, NH4Mo, and the combination of them did not impair the quality parameters including fruit firmness and content of total soluble solids, titratable acidity and vitamin C of peach fruit after 6days of storage at 20°C. These results suggested that the use of NH4Mo is a useful approach to improve the efficacy of P. membranifaciens for postharvest disease control in peach fruit. [Copyright &y& Elsevier]

Abstract: The effect of hot air treatment (HAT) on reducing natural fungal decay and green mould decay caused by Leptographium abietinum on postharvest Chinese bayberry fruit and the possible mechanisms were investigated. Freshly harvested Chinese bayberry fruit were firstly pretreated with hot air at 36–60°C for 1–3h, and then stored at 20°C for 3d or at 1°C for 12d to investigate the optimum condition of hot air treatment (HAT) for inhibiting decay development. Results demonstrated that HAT at 48°C for 3h was the most effective in reducing natural decay without impairing quality. This treatment also enhanced the resistance of Chinese bayberry fruit against green mould rot caused by L. abietinum and reduced the severity of the disease. The activities of defense-related enzymes including chitinase, β-1, 3-glucanase, peroxidase and polyphenol oxidase were significantly enhanced by HAT. In addition, the in vitro experiment showed that HAT significantly inhibited spore germination, germ tube elongation and mycelial growth of L. abietinum. These results indicate that HAT can effectively reduce fruit decay possibly by directly inhibiting pathogen growth and indirectly inducing disease resistance. [Copyright &y& Elsevier]

Abstract: The effects of ultrasound treatment on fruit decay and physiological quality of strawberry fruit were investigated. Freshly harvested strawberries were treated with 0, 25, 28, 40 or 59kHz ultrasound at 20°C for 10min and then stored at 5°C for 8days. The results showed that 40kHz ultrasonic treatment significantly reduced decay incidence and numbers of microorganism. Ultrasound treatment also inhibited the decrease of firmness and maintained significant higher levels of total soluble solids (TSS), total titratable acidity (TA) and vitamin C. Treatments with 25 and 28kHz ultrasound had no significant effects on fruit decay and quality deterioration of strawberry fruit. Thus, ultrasound treatment has potential to extend shelf-life and maintain quality in strawberry fruit. [Copyright &y& Elsevier]

Abstract: Freshly harvested strawberry fruit were treated at ultrasonic powers from 250 to 450W at a constant frequency of 40kHz for different times (5–15min). Response surface methodology (RSM) based on a two factors three level central composite design was applied to optimize ultrasonic treatments on decay incidence, microbial population and quality maintenance of strawberries. According to response surface analysis, the optimal treatment parameters were an ultrasonic power of 250W and treatment time of 9.8min. Decay incidence and quality parameters of strawberries treated at the determined optimum conditions were compared with a water treatment during storage for 8d at 5°C. An ultrasonic treatment was found to be effective in inhibiting decay incidence and preserving quality in strawberries, and these results suggest that such a treatment may provide an alternative for extending shelf-life and maintaining quality of strawberry fruit. [Copyright &y& Elsevier]

Abstract: Loquat fruit were pretreated with 10μM methyl jasmonate (MeJA) for 24h at 20°C, and then stored at 1°C for 35days to investigate the effect of MeJA treatment on cell wall modification in relation to chilling injury. Loquat fruit developed chilling injury, manifested as increased fruit firmness and internal browning, decreased extractable juice during storage. These chilling injury symptoms were significantly reduced by MeJA treatment. MeJA also markedly delayed the increases in lignin, alcohol insoluble residues, hemicellulose and cellulose. Meanwhile, the MeJA-treated fruit exhibited significantly lower activities of phenylalanine ammonia lyase, peroxidase, polyphenol oxidase and higher polygalacturonase activity than the control during storage. The levels of water- and CDTA-soluble pectins in MeJA-treated fruit were also significantly higher than that in the control. These results suggest that the reduction in chilling injury by MeJA may be due to inhibited lignin accumulation and enhanced cell wall polysaccharides solubilisation. [Copyright &y& Elsevier]

Abstract: Loquat fruit were pre-treated with 10μmol/l methyl jasmonate (MeJA) for 24h at 20°C, and then stored at 1°C for 35days to investigate the effect of MeJA treatment on chilling injury and changes in the antioxidant system. Loquat fruit developed chilling injury, manifested as increased fruit firmness, decreased extractable juice rate and internal browning during storage. These chilling injury symptoms were significantly reduced by MeJA treatment. MeJA also markedly delayed the increases in O2 − production rate and H2O2 content. Meanwhile, the MeJA-treated fruit exhibited significantly higher activities of superoxide dismutase, catalase and ascorbate peroxidase, and lower activity in lipoxygenase than control fruit during the storage. The ratio of unsaturated/saturated fatty acid in MeJA-treated fruit was also significantly higher than that in control fruit. These results suggest that the reduction in chilling injury by MeJA may be due to enhanced antioxidant enzyme activity and higher unsaturated/saturated fatty acid ratio. [Copyright &y& Elsevier]

Abstract: The beneficial effect of 2% CaCl2 (w/v) on the antagonistic yeast Pichia membranifaciens for control of anthracnose rot caused by Colletotrichum acutatum in postharvest loquat fruit (Eriobotrya japonica L.) and the possible mechanisms involved were investigated. The results showed that treatment with P. membranifaciens at 1×108 CFU ml−1 or 2% CaCl2 alone both resulted in significantly smaller lesion diameter and lower disease incidence of anthracnose rot on loquat fruit wounds compared with the controls. The biocontrol activity of P. membranifaciens on the disease was enhanced by the addition of 2% CaCl2, the combined treatment of P. membranifaciens with CaCl2 resulted in a remarkably improved control of the disease in comparison with the treatment of P. membranifaciens or CaCl2 alone. P. membranifaciens in combination with CaCl2 induced higher activities of two defense-related enzymes chitinase and β-1,3-glucanase in loquat fruit than applying the yeast or CaCl2 alone. The in vitro experiment showed that the addition of 2% CaCl2 in the suspensions of P. membranifaciens significantly inhibited spore germination and germ tube elongation of C. acutatum than the yeast or CaCl2 alone. However, adding CaCl2 did not significantly influence the population of P. membranifaciens in NYDB medium or fruit wounds. These results suggest that CaCl2 could improve the biocontrol activity of P. membranifaciens on anthracnose rot in loquat fruit. It is postulated that the improved control of the disease is directly because of the higher inhibitory effect on pathogen growth and indirectly because of the enhanced disease resistance in loquat fruit by the combination treatment. [Copyright &y& Elsevier]

The effect of methyl jasmonate (MeJA) on reducing anthracnose rot caused by Colletotrichum acutatum infection in postharvest loquat fruit (Eriobotrya japonica L. cv. Jiefangzhong) and the possible mechanisms involved were investigated. Freshly harvested loquat fruit were treated with 10μmol/L MeJA at 20°C for 24h. Both the treated and the untreated fruit were artificially wounded and inoculated with Colletotrichum acutatum spore suspension (1.0×105 spores/mL) 1 day after the treatment, and then incubated at 20°C for 6 days. Treatment of loquat fruit with MeJA resulted in significantly lower disease incidence and smaller lesion diameters than in control fruit. MeJA treatment significantly inhibited activities of catalase (CAT) and ascorbate peroxidase (APX) while superoxide dismutase (SOD) activity was not significantly affected in early infection, thus resulting in a higher level of H2O2 in the earlier period of incubation. The enhanced H2O2 generation by MeJA treatment might serve as a signal to induce resistance against C. acutatum infection. However, MeJA treatment inhibited the increase in phenylalanine ammonia-lyase (PAL), polyphenoloxidase (PPO) and peroxidase (POD) activities and lignin content, indicating that lignification is not the major defense mechanism against anthracnose rot in loquat fruit. The in vitro experiment showed that MeJA significantly inhibited spore germination, germ tube elongation and mycelial growth of C. acutatum. These results suggest that MeJA treatment can effectively inhibit anthracnose rot caused by C. acutatum in postharvest loquat fruit. It is postulated that the control of the disease is directly because of the inhibitory effect of MeJA on pathogen growth, and indirectly because of the induced disease resistance triggered by enhanced H2O2 levels. [Copyright &y& Elsevier]

• Near-saturated relative humidity storage alleviated chilling injury in zucchini. • NSH storage maintained lower activities of lipoxygenase and phospholipase D. • NSH-fruit manifested higher membrane lipid unsaturation during cold storage. • Chilling tolerance in NSH-fruit was related to a higher level of energy status. To investigate the effect of relative humidity (RH) on chilling injury (CI), zucchini fruit were stored in cold rooms (4 ± 0.4 ℃) with different RHs (near-saturated RH [NSH] with 96–100% and normal RH with 72–76% served as control). Storage in NSH delayed weight loss and CI, maintained firmness and skin color. Higher antioxidant enzyme activities and greater scavenging capacities of free radicals were found in NSH-fruit than in the control fruit. The decrease of the unsaturated fatty acids was delayed in NSH-fruit due to lower activities of related membrane lipid degrading enzymes as compared to the control fruit. NSH-fruit also maintained higher activities of energy metabolism-associated enzymes than control fruit, leading to high levels of adenosine triphosphate (ATP). Taken together, we attributed the alleviation of CI by NSH storage to its enhancement of antioxidant capacities and its effect on maintaining higher energy status in zucchini fruit. [ABSTRACT FROM AUTHOR]