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SummaryThe effect of Pichia membranefaciens on reducing post-harvest anthracnose rot caused by Colletotrichum acutatum in loquat fruit was investigated. Fruit were treated with different suspensions of P. membranefaciens before challenge with 1.0 105 spores ml–1 of C. acutatum, then incubated at 20°C for 6 d. The results showed that 1 108 colony-forming units (CFU) ml–1 of washed cell suspensions of the yeast provided better control of anthracnose rot than yeast in culture broth at the same concentration. Treatment with autoclaved cell cultures or culture filtrates did not prevent the incidence of disease. The concentration of a washed cell suspension of P. membranefaciens had a significant effect on the efficacy of controlling anthracnose rot in loquat fruit. At a concentration range from 1 106 to 1 109 CFU ml–1, the higher the concentration of the antagonist, the lower the incidence of the disease and the smaller the diameter of the lesions. In inoculated wounds of loquat fruit, populations of P. membra...

The influence of storage temperature on textural properties of Chinese bayberry fruit was investigated by using instrumental texture profile analysis (TPA). The fruit was harvested at ripe stage and stored at 20, 10 and 1C for 60 h, 5 and 14 days, respectively, and six textural parameters were measured. There was a decrease in fruit firmness, cohesiveness, springiness, resilience and chewiness, and an increase in adhesiveness during storage. Increased storage temperature resulted in accelerated decrease in fruit firmness, cohesiveness, springiness, resilience and chewiness, and an increase in adhesiveness. There was a significant correlation among the six TPA parameters. Low temperature inhibited the decrease of total soluble solids, total titratable acidity and increase of flesh pH value, thereby maintaining better taste quality. TPA parameters could be used as suitable indicators of fruit quality and storability, and low temperature storage is beneficial for delaying textural changes and maintaining the taste quality of Chinese bayberry fruit after harvest. PRACTICAL APPLICATIONS The research reported in this article is relevant and of interest to both researchers and industry. Because our results confirm that TPA is a reliable instrumental measurement for evaluating the textural quality and fruit softening of Chinese bayberry fruit during storage, the measurement of TPA parameters may have the potential to provide useful information for quality control in industry, and to serve as objective indicators of fruit quality and storability for postharvest researchers to develop more suitable handling, transportation and storage techniques of Chinese bayberry fruit. Moreover, our finding that low temperature storage was beneficial for delaying textural changes and maintaining the taste quality of Chinese bayberry fruit will help industry to determine the suitable temperature for storage of this fruit.

This study investigated the regulation of ascorbate acid (AsA) and glutathione metabolism and chilling tolerance by methyl jamonate (MeJA) in loquat fruit. The results showed that application of MeJA to loquat fruit inhibited the incidence of chilling injury manifested as internal browning (IB) and increased AsA and reduced glutathione (GSH) contents due to the inhibition of ascorbate oxidase activity and enhancement of monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase activities. Meanwhile, MeJA also enhanced activities of ascorbate peroxidase, glutathione peroxidase and glutathione-S-transferase. Our results suggested that MeJA can regulate the ascorbate and glutathione metabolism and has important roles in alleviating oxidative damage and enhancing chilling tolerance in loquat fruit.

Two cultivars of Chinese bayberry fruit cvs 'Dongkui' and 'Biqi' with five different ripening stages were used to investigate the relationship between anthocyanin biosynthesis and sugar metabolism during fruit development. The results showed that anthocynin accumulated with the increased ripening stage in both of the two cultivars of bayberries. As compared to 'Biqi' fruit, a higher level of anthocyanin content was observed in 'Dongkui' fruit due to the increased expression of anthocyanin biosynthetic and regulatory genes especially MrCHI, MrDFR1, MrANS, and MrMYB1. Meanwhile, 'Dongkui' fruit also experienced higher levels of soluble sugars including sucrose, glucose, and fructose and expression of genes such as MrSPS1, MrSPS2, MrSPS3, MrINV1, MrINV2, and MrINV3 involved in sugar metabolism. Correlation analysis showed anthocyanin content had a significant relationship with all the three soluble sugars in bayberry fruit. Therefore, our results suggested that the higher anthocyanin content in 'Dongkui' fruit might be associated with its increased levels of soluble sugars.

Blue light irradiation was applied to postharvest strawberry fruit to explore its influence on anthocyanin content and anthocyanin biosynthetic enzyme activities. Strawberry fruit was irradiated with blue light at 40 μmol m(-2) s(-1) for 12 days at 5 °C. The results indicated that blue light treatment improved total anthocyanin content in strawberry fruit during storage. Meanwhile, the treatment increased the activities of glucose-6-phosphate, shikimate dehydrogenase, tyrosine ammonia-lyase, phenylalanine ammonia-lyase, cinnamate-4-hydroxylase, 4-coumarate/coenzyme A ligase, dihydroflavonol-4-reductase, chalcone synthase, flavanone-3-β-hydroxylase, anthocyanin synthase, and UDP-glycose flavonoid-3-O-glycosyltranferase, which suggested that the enhancement of anthocyanin concentration by blue light might result from the activation of its related enzymes. Blue light might be proposed as a supplemental light source in the storage of strawberry fruit to improve its anthocyanin content.

The aim of this work is to investigate the effects of domestic cooking methods, including steaming, microwave heating, boiling and stir-frying on the nutritional quality of red cabbage. Compared with fresh-cut red cabbage, all cooking methods were found to cause significant reduction in anthocyanin and total glucosinolates contents. Moreover, steaming resulted in significantly greater retention of vitamin C and DPPH radical-scavenging activity, while stir-frying and boiling, two popular Chinese cooking methods, led to significant losses of total phenolic, vitamin C, DPPH radical-scavenging activity, and total soluble sugar as well as reducing sugars. Normally, red cabbage consumed fresh in salads could maintain the highest nutrition. However, considering the habits of Asian cuisine, it is recommended to use less water and less cooking time, such as steaming based on our present results, so as to retain the optimum benefits of the health-promoting compounds.

The effect of 3.0kJ/m(2) ultraviolet-C (UV-C) treatment on respiratory activity and mitochondrial membrane associated with fruit senescence in peach fruit stored at 20°C for 8days was investigated. UV-C treatment could reduce senescence development, as evidenced by higher fruit firmness due to inhibition of respiration rate via reducing succinic dehydrogenase and cytochrome C oxidase activity. Meanwhile, the activities of superoxide dismutase, catalase and ascorbate peroxidase in the UV-C-treated fruit were much higher than those in control fruit, resulting in lower levels of superoxide radicals (O2(-)) and hydrogen peroxide (H2O2). In addition, this treatment maintained a higher level of mitochondrial membrane fluidity and inhibited opening of mitochondrial permeability transition pore. Our results suggest that the induction of antioxidant enzymes to scavenge O2(-) and H2O2 by UV-C treatment was associated with the maintenance of mitochondrial membrane integrity, which also played an important role in senescence retardation in peach fruit.

The effect of methyl jasmonate (MeJA) on changes in polyamines content and energy status and their relation to disease resistance was investigated. Freshly harvested loquat fruit were treated with 10 μmol l(-1) MeJA and wound inoculated with Colletotrichum acutatum spore suspension (1.0 × 10(5) spores ml(-1)) after 24h, and then stored at 20 °C for 6 days. MeJA treatment significantly reduced decay incidence. MeJA treated fruit manifested higher contents of polyamines (putrescine, spermidine and spermine) compared with the control fruit, during storage. MeJA treatment also maintained higher levels of adenosine triphosphate, and suppressed an increase in adenosine monophosphate content in loquat fruit. These results suggest that MeJA treatment may inhibit anthracnose rot by increasing polyamine content and maintaining the energy status.

Loquat (Eriobotrya japonica Lindl.) is a subtropical evergreen tree whose fruit is consumed both fresh and processed. Loquat fruit is a good source of minerals and carotenoids, while the kernel is rich in protein and carbohydrates. It has been considered a non-climacteric fruit, but there is evidence that some cultivars have a ripening pattern similar to that of climacteric fruits. The fruit has a short postharvest life at ambient temperatures and is susceptible to physical and mechanical damage, loss of moisture and nutrients, and decay. Low-temperature storage extends the shelf life of loquat fruit, but some cultivars are severely affected by chilling injury and flesh browning during cold storage. Purple spot, browning and leatheriness are major postharvest disorders. The shelf life of loquat can be extended by modified or controlled atmosphere storage as well as by postharvest treatment with 1-methyl cyclopropene or methyl jasmonate.

To analyze the effectiveness ofvolar locking compression plate (LCP) and radial styloid process plate for the treatment of type C fractures of the distal radius.Between May 2010 and May 2011, 24 cases of type C fractures of the distal radius were treated, including 8 males and 16 females with an average age of 52 years (range, 23-73 years). Injury was caused by falling in 20 cases and by traffic accident in 4 cases. All were fresh closed fractures. The locations were the left side in 15 cases and the right side in 9 cases. According to AO typing, there were 16 cases of type C2 and 8 cases of type C3. The preoperative palmar tilt angle ranged from 60 to 25 degrees (mean, -45.3 degrees); the preoperative ulnar inclination angle ranged from 16 to 13 degrees (mean, 8.2 degrees); and the preoperative radial length shortening was 8-18 mm (mean, 12 mm). The time from injury to operation was 3-10 days (mean, 5.2 days).All operation incisions healed primarily. All patients were followed up 9-16 months (mean, 13.5 months). The healing time of fracture was 8-12 weeks (mean, 10.2 weeks). The articular surface was smooth and the radial length was recovered. The postoperative palmar tilt angle ranged from 8 to 15 degrees (mean, 12.3 degrees); the postoperative ulnar inclination angle ranged from 18 to 26 degrees (mean, 22.3 degrees). No loss of reduction, refracture, or carpal tunnel syndrome occurred during follow-up. The average range of motion of the wrist was 45.3 degrees (range, 30-70 degrees) in dorsal extension, was 50.2 degrees (range, 26-78 degrees) in palmar flexion, was 13.5 degrees (range, 8-25 degrees) in radial inclination, was 23.6 degrees (range, 15-32 degrees) in ulnar inclination, was 65.7 degrees (range, 35-90 degrees) in pronation, and was 72.5 degrees (range, 20-90 degrees) in supination at last follow-up. According to the wrist function by Gartland-Werley scoring, the results were excellent in 12 cases, good in 8 cases, and fair in 4 cases; and the excellent and good rate was 83.3%.Treatment of type C fractures of the distal radius with volar LCP and radial styloid process plate can reconstruct normal anatomic structures and get good functional recovery.

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 5 mM 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. (C) 2012 Elsevier Ltd. All rights reserved.

The effects of salicylic acid (SA; 1 mmol L(-1)) and ultrasound treatment (40 kHz, 10 min) either separately or combined on the chilling injury (CI) in cold-stored peach fruit ( Prunus persica Batsch cv. Baifeng) were investigated. The results showed that SA treatment alone alleviated CI during storage. Ultrasound alone had no influence, but when it was combined with SA, it resulted in greater inhibition of CI than SA alone. The activities of antioxidant enzymes, such as catalase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase, were induced by a combination of SA with ultrasound. In addition, the combined treatment also increased the endogenous SA concentrations in peaches. These results suggested that the induced tolerance against CI by the combination of ultrasound and SA treatment in cold-stored peach fruit was related to the induction of antioxidant enzymes and the increase in the SA concentration.

The effect of the yeast antagonist Pichia membranaefaciens for control of green mould decay caused by Penicillium citrinum or Verticicladiella abietina and natural decay in postharvest Chinese bayberries (Myrica rubra Seib & Zucc.), and the possible mechanisms were investigated. The results showed that 1 x 10 9 colony-forming units (CFU)/ml of washed cell suspensions of the yeast provided better control of green mould decay than yeast in culture broth at the same concentration. Treatment with cell-free culture filtrates or autoclaved cell cultures had little effect on disease incidence. The concentration of a washed cell suspension of P. membranaefaciens had a significant effect on efficacy in controlling disease incidence. At a concentration range from 1 × 10 6 to 1 × 10 9 CFU/ml, the higher the concentration of the antagonist, the lower was the incidence of the disease. In the inoculated wounds of Chinese bayberries, populations of P. membranaefaciens increased by approximately 145- and 41-fold, respectively, after incubation at 20°C for 2 day or at 1°C for 8 day. P. membranaefaciens significantly induced activities of two defence-related enzymes chitinase and β-1, 3-glucanase in Chinese bayberries. The in vitro experiment showed that spore germination and germ tube elongation of the two pathogens were markedly inhibited by washed cell suspensions of P. membranaefaciens. In addition, P. membranaefaciens significantly reduced natural decay in Chinese bayberries. These results indicate that P. membranaefaciens can effectively reduce fruit decay possibly by directly inhibiting pathogen growth and indirectly by inducing disease resistance. Thus, we suggest that P. membranaefaciens has potential as a biocontrol agent to control fruit decay in Chinese bayberries during postharvest storage.

BACKGROUND: ‘Hami’ melon is susceptible to softening during postharvest storage at ambient temperature, which enhances postharvest deterioration and limits transportation and storage. To look for a method of softening control, the effect of 1-methylcyclopropene (1-MCP) on regulating postharvest softening of ‘Hami’ melon fruit was investigated. RESULTS: 1-MCP treatment at 1 µL L−1 significantly reduced ethylene production and maintained higher levels of fruit firmness. It also markedly inhibited the accumulation of 1-aminocyclopropane-1-carboxylic acid (ACC) and maintained lower activities of ACC synthase and ACC oxidase. In addition, 1-MCP treatment reduced the activities of fruit-softening enzymes such as pectin methyl esterase, polygalacturonase, endo-1,4-β-glucanase and β-galactosidase. CONCLUSION: 1-MCP was effective in suppressing ethylene production and delaying fruit softening in ‘Hami’ melon by decreasing the activities of ethylene biosynthesis enzymes and inhibiting fruit-softening enzymes. Copyright © 2011 Society of Chemical Industry

Chilling injury (CI) limits the storage period and shelf-life of red-fleshed loquat fruit (Eriobotrya japonica Lindl.), which leads to a remarkable loss after cold storage. To develop an effective technique to reduce CI, the effects of a 38 degrees C heat treatment in air for 5 h, plus storage at 1 degrees C for 35 days, on internal browning (IB) and membrane fatty acid composition of the loquat cv. Jiefangzhong were investigated.Heat treatment delayed the occurrence of IB and inhibited the increase of IB index in 'Jiefangzhong' loquat fruit. Heat treatment maintained lower levels of electrolyte leakage and malondialdehyde content, and inhibited the increases in phospholipase D and lipoxygenase activities compared with the control fruit. Meanwhile, heat treatment inhibited the increases in palmitic, stearic and oleic acid levels and delayed the decreases in linoleic and linolenic acid contents, thus maintaining higher unsaturated/saturated fatty acid ratio than the control.These results suggest that the reduction of IB in chilled loquat fruit by heat treatment might due to maintenance of membrane integrity and higher unsaturated/saturated fatty acid ratio.

The effect of benzo-thiadiazole-7-carbothioic acid S-methyl ester (BTH) at 0.2 g L(-1) on anthocyanin content and the enzymes involved in its metabolism such as glucose-6-phosphate dehydrogenase (G6PDH), shikimate dehydrogenase (SKDH), tyrosine ammonia lyase (TAL), phenylalanine ammonia lyase (PAL), cinnamate-4-hydroxylase (C4H), 4-coumarate/coenzyme A ligase (4-CL), and dihydroflavonol 4-reductase (DFR) in strawberry (Fragaria x ananassa Duch.) fruit was investigated in this study. The result showed that BTH treatment gave higher levels of anthocyanin in strawberries during 10 days of storage at 1 degrees C. Meanwhile, the treatment also increased the activities of G6PDH, SKDH, TAL, PAL, C4H, and DFR. These results indicated that the increase in anthocyanin content by BTH might result from the activation of its related enzymes. These data are the first evidence that BTH induces enzyme activities related to anthocyanin metabolism in strawberry fruit after harvest.

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 degrees C for 1-3h, and then stored at 20 degrees C for 3d or at 1 degrees C for 12d to investigate the optimum condition of hot air treatment (HAT) for inhibiting decay development. Results demonstrated that HAT at 48 degrees 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, beta-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.

The effects of methyl jasmonate (MeJA) on postharvest decay and antioxidant capacity in harvested Chinese bayberry fruit were investigated. Chinese bayberries were treated with 0, 1, 10, 100, or 1000 micromol L(-1) MeJA at 20 degrees C for 6 h and then stored at 0 degrees C for 12 days. MeJA at 10 micromol L(-1) was most effective in reducing fruit decay; quality parameters including pH value, total soluble solids, and titratable acidity were not significantly affected by MeJA treatment. Fruit treated with 10 micromol L(-1) MeJA exhibited significantly higher phenylalanine ammonia-lyase activity and higher levels of total phenolics, flavonoids, and anthocyanins as well as individual phenolic compounds than control. These fruits also maintained significantly higher antioxidant activity as measured by scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl, superoxide, and hydroxyl radicals and by the reducing power test compared to the control. These results indicate that MeJA can effectively reduce fruit decay and improve antioxidant capacity of Chinese bayberry fruit.

The influence of high O(2) atmosphere on postharvest decay, quality, total phenolic, total anthocyanin contents, antioxidant enzymes activity, and antioxidant activity of Chinese bayberry fruit was investigated. Freshly harvested Chinese bayberry fruits were placed in jars and ventilated continuously with air or with 80 and 100% O(2) for up to 12 days. Samples were randomly selected initially and at 3-days interval during storage. The fruit exposed to high O(2) was resistant to decay, had high levels of total soluble solids, titratable acidity and ascorbic acid contents, and also reduced the increment of pH value. High O(2) treatment was less stressful as reflected by having the significantly lower malonaldehyde contents and higher catalase, ascorbic acid peroxidase, and peroxidase activities during storage. Both 80% and 100% O(2) treaments had also retained the bioactive contents and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity during storage. These results indicate that elevated O(2) levels may improve the ability of the antioxidative defense mechanism in Chinese bayberry and result in a better control of fruit decay.

Hypersensitive-induced reaction (HIR) proteins, which are members of the proliferation, ion and death (PID) superfamily, have been shown to be involved in the defense responses of several plant species. In this study, three HIR-like genes from soybean, designated as GmHIR1, GmHIR3 and GmHIR4, were cloned and characterized. They each contained four introns and five exons and shared conservative structure of genomic organization. The deduced polypeptide sequences of GmHIRs share high degrees of similarity with HIR proteins of other species. However, QRT-PCR analysis indicated that the expression levels in different tissues were not the identical. The expression of GmHIRs were rapidly induced by Phytophthora sojae infection in the resistant genotype, while induction was very weak in the susceptible genotype. In addition, the expression of these genes were also repressed by hydrogen peroxide (H2O2) treatment. Promoter analysis indicates that several defenseresponsive elements are present in the GmHIR promoter. To our knowledge, this is the first report on molecular cloning and initial characterization of HIR-like genes in soybean. This study may help elucidate soybean disease resistance, which would enhance efforts to control soybean Phytophthora root and stem rot disease.

OBJECTIVE: To observe the expression and cellular localization of interleukin-8 (IL-8) mRNA and protein in the area of xenogenic bone implant. METHODS: The bovine cancellous bone granules were implanted into the thigh muscles of mice. The samples were taken 4, 7, 14 and 21 days after implantation. IL-8mRNA and protein in the site of implant were assayed by in situ hybridization and immunocytochemical techniques. RESULTS: The expression of IL-8mRNA and protein were observed in all specimens 4, 7, 14 and 21 days after implantation. IL-8mRNA was expressed mainly by the neutrophils, monocytes, macrophages and fibroblasts at 7th day post-implantation. Some mesenchymal cells, multinucleated giant cells, vascular endothelial cells and smooth muscle cells also expressed IL-8mRNA in the area of xenogenic bone implant at 14th and 21st days. Immunocytochemical studies demonstrated the same results as that of in situ hybridization. CONCLUSIONS: Many different kinds of cells express IL-8mRNA and secret IL-8 in the area of xenogenic bone implant, suggesting that IL-8 may play an important role in local immunity of xenogenic bone graft.