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1.
经10%高CO2预处理10天的富士苹果果实,在10℃贮藏150天后,果肉硬度大,失重率低,可溶性固形物含量较高,丙二醛含量和乙醇含量的增加受到抑制,乙烯高峰出现时间延迟,总酚含量达2.75mg/g,是对照组的1.4倍,果实品质得到较好的保持。5%CO2预处理10天的富士果实贮藏后期的乙醇含量较高;20%CO2预处理的富士果实在贮藏60天时CO2伤害果检出率达到32%。  相似文献   

2.
以富士苹果为试材,研究1-MCP和CO2高透性保鲜袋气调包装(MAP)对富士苹果贮藏品质的影响。结果表明:1-MCP和CO2高透性保鲜袋气调包装均能有效抑制富士苹果贮藏过程中呼吸强度的增加,减缓果实硬度、SSC和TA含量的下降,抑制果实失重率的增加。其中,1-MCP结合CO2高透性保鲜袋气调包装处理效果更佳,更好地保持果实的品质。  相似文献   

3.
变动气调贮藏保持大久保桃品质的研究   总被引:7,自引:0,他引:7  
研究了大久保桃在变动气调(Dynamic controlled atmosphere,DCA)、常规气调5%O2+10%CO2(Controlled atmosphere,CA)和普通冷藏(对照)条件下0~1℃贮藏70d及20℃货架3d后果实的生理变化、冷害症状和感官品质。结果表明,与对照相比,DCA和CA贮藏均能有效地减少果实的腐烂和褐变,保持果实硬度,减轻果肉组织伤害,降低果实冷敏感性,提高贮后品质;与CA贮藏相比,DCA处理效果更好。  相似文献   

4.
【目的】探索‘富士’苹果果实长期贮藏过程中的最适O_2/CO_2比例,为采后‘富士’苹果果实贮藏提供理论依据。【方法】以‘富士’苹果果实为材料,在(1±0.5)℃贮藏条件下,采用不同比例O_2/CO_2简易气调长期贮藏,测定不同贮藏条件下果实品质、相对电导率、丙二醛(MDA)、ATP、过氧化氢(H_2O_2)含量、超氧阴离子(O_2~-)生成速率、PLD、SOD、线粒体H~+-ATPase、线粒体Ca~(2+)-ATPase、SDH和CCO活性的指标,从膜脂代谢和能量代谢两个角度来分析不同比例O_2/CO_2简易气调过程中‘富士’果实发生CO_2伤害的原因。【结果】‘富士’苹果长期贮藏过程中,不同比例O_2/CO_2简易气调均可有效维持果实质量、硬度、可滴定酸含量、可溶性固形物含量;但当处理中O_2浓度小于10%、CO_2浓度大于5%时,果实发生CO_2伤害,果实中与能量产生相关的线粒体H~+-ATPase、线粒体Ca~(2+)-ATPase、SDH、CCO活性降低,ATP含量减小,同时SOD活性减弱,O_2~-、H_2O_2产生增加,PLD活性被激活,膜结构的完整性被破坏,褐变发生。【结论】‘富士’苹果果实长期贮藏过程中保鲜效果最好的是处理Ⅰ(3%CO_2+12%O_2+85%N_2),当O_2浓度小于10%、CO_2浓度大于5%时,细胞维持较低能量水平,膜脂过氧化严重,CO_2伤害发生。  相似文献   

5.
研究了‘富士’苹果分别在0.00、-0.02、-0.04、-0.06MPa的大气压下处理5min,1-MCP熏蒸24h,(-1±1)℃贮藏210d的品质变化。结果表明:1-MCP和减压处理可以减缓果肉硬度下降,可以有效抑制‘富士’苹果可滴定酸、可溶性固形物含量的下降,显著抑制果实乙烯释放量,显著降低呼吸速率,保持了其贮藏期的品质,延缓其衰老速率。在供试的5个负压条件中,以-0.06MPa压强处理效果最佳。  相似文献   

6.
以乔纳金苹果为试材,在不同气贮藏条件下进行试验,当未脱除贮藏环境中的乙烯时,以在1%CO2 1%O2条件下贮藏的果实硬度最大。在脱除乙烯条件下,5%CO2 3%O2气调处理的果实硬度明显高于未脱除乙烯的相同处理;在低氧和低二氧化碳气调(1%CO2 1%O2)贮藏条件下,贮后果实的硬度与乙烯的关系不大。果实贮前用2%的二氧化碳处理10天,然后在5%CO2 3%O2气调下贮藏,可以显著地延迟后熟。乔纳金苹果的果实对高CO2和低O2不敏感。贮前用高二氧化碳处理后在5%CO2 3%O2气调下贮藏,及低O2和低CO2(1%CO2 1%O2)贮藏乔纳金苹果效果最好。  相似文献   

7.
气调对比试验结果表明:气调贮藏可显著抑制富士苹果果实硬度的下降,减少内源乙烯含量,贮藏寿命达8 个月,并可保持其品质;富士苹果果肉褐变的主要原因是CO2 浓度的升高,降低O2 浓度加剧富士苹果CO2 伤害的程度;贮期过长、果实衰老也可导致富士苹果的果肉褐变;2 % CO2+ 5 % O2 是富士苹果气调贮藏的理想指标  相似文献   

8.
气调贮藏对富士苹果采后生理及果肉褐变的影响   总被引:12,自引:1,他引:11  
石建新  赵猛 《果树科学》1999,16(1):14-17
气调对比试验结果表明:气调贮藏可显著抑制富士苹果果实硬度的下降,减少内源乙一贮藏寿命达8个月,并可保持其品质,富士苹果果肉褐变的主要原因是CO2浓度的升高,降低O2浓度加剧富士苹果CO2伤害的程度;贮期过长,果实衰老也可导致富士苹果的果肉褐变;2%CO2+5%O2是富士苹果气调贮藏的理想指标。  相似文献   

9.
以低密度聚乙烯为主料,添加轻质碳酸钙、重质碳酸钙、大豆油等功能性辅料,自制CO2高透性保鲜膜,利用该保鲜膜对"富士"苹果进行自发气调贮藏,通过测定保鲜袋内气体成分变化、果实硬度、褐变指数、乙醇含量等指标,观察该保鲜膜对"富士"苹果的贮藏效果。结果表明:3种功能性辅料的添加总量为10%时,生产的保鲜膜性能达到"富士"苹果贮藏要求,可显著降低微环境中CO2浓度,保持果实的硬度、降低褐变指数和减少乙醇的积累,维持较好的果实品质。  相似文献   

10.
拮抗酵母菌(Rhodotorulaglutinis)在20~25℃的室温下生长较快,即使20%CO2亦不能抑制其生长,但菌落直径扩展速度与CO2浓度(0~20%)呈显著负相关(r=-0.8999~-0.9383)。R.glutinis在低温(1℃)条件下,对CO2较敏感,15%CO2浓度可以抑制该拮抗菌在低温下生长,但将其移到常温下培养2d后即可生长。另外,5%或15%CO2单独使用不能抑制Alternariaalternata(1×104个孢子/mL,15μL)在红灯樱桃果实上萌发,但可极显著地抑制其病斑在樱桃果实上的扩展速度。R.glutinis悬浮液(108cfu/mL)与5%或15%CO2结合使用则可完全抑制A.alternata在樱桃果实上生长。  相似文献   

11.
AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β-particles emission from 188Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by 188Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [3H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of 188Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from 188 Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G0/G1 arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.  相似文献   

12.
AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P<0.01). The ET content in plasma also decreased significantly by L-Arg(P<0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.  相似文献   

13.
多效唑对猕猴桃离体试管苗生长及内源激素的影响   总被引:18,自引:0,他引:18  
多效唑(PP333)处理猕猴桃试管苗,降低了其生长强度;植株体内的GA3、IAA和ZT含量下降,ABA的含量上升,乙烯释放率增加;并且能降低外源的GA3和IAA促进生长的作用,而外源的GA3和IAA又能不同程度地逆转多效唑的抑制作用,使植株恢复生长。  相似文献   

14.
AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.  相似文献   

15.
Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.  相似文献   

16.
The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.  相似文献   

17.
Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.  相似文献   

18.
AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.  相似文献   

19.
AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [3-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10-6-10-4 mmol/L) stimulated [3-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [3-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P<0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P<0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10-6-10-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P<0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl2 for 6 h induced an increase cellular MT content by 5.7-fold (P<0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P<0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.  相似文献   

20.
Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r 2) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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