1-甲基环丙烯处理对西洋梨常温贮藏的保鲜效果

为了探索西洋梨采后的常温保鲜方法,以“早红考密斯”为试材,研究了1-甲基环丙烯处理对西洋梨果实在20℃条件下生理代谢的影响。结果表明,在20℃贮藏条件下,1-MCP处理能明显延缓果实硬度的下降和色度的改变;抑制果实乙烯的合成,降低果实的呼吸速率,推迟乙烯、呼吸峰出现,并降低峰值。1-MCP处理与对照相比,乙烯释放高峰和呼吸高峰推迟6 d出现,同时降低了峰值,乙烯释放高峰和呼吸高峰分别仅为对照的69.6%和79.8%;1-MCP处理抑制了可溶性固形物含量和丙二醛含量的快速上升;在贮藏12 d时,果实的过氧化物酶、超氧化物歧化酶、过氧化氢酶活性分别为对照的 144.7%、113.5%、141.4%;另外,1-MCP还可以抑制果实的腐烂,降低果实腐烂率。因此,1-MCP处理可抑制西洋梨货架期的后熟衰老进程,有利于保持果实品质,提高贮藏效果。     

适宜1-MCP处理保持采后菠萝常温贮藏品质

为了探索1-MCP处理对采后菠萝生理及品质的影响,为菠萝贮藏保鲜措施提供理论依据。以‘巴厘’品种的菠萝果实为试材,采用适宜0.45μL/L体积分数的1-MCP对菠萝进行处理,置于25℃条件下贮藏,采用气相色谱定期测定乙烯释放量,并采用常规理化分析方法测定菠萝品质及相关生理指标。结果表明,1-MCP处理能延缓果实贮藏过程中乙烯的合成速率,与相同贮藏条件下的对照(未处理)果实相比,乙烯释放高峰推迟4 d;1-MCP处理可以延缓果实丙二醛(malondialdehyde,MDA)含量的快速升高,同时对脂氧合酶(lipoxygenase,LOX)酶活性起到抑制作用;与对照相比,1-MCP处理推迟了过氧化物酶(peroxidase,POD)、过氧化氢酶(catalase,CAT)等酶活性高峰的出现,并使POD、CAT、过氧化物歧化酶(superoxide dismutase,SOD)等保持较高的活性,可以有效延缓菠萝在贮藏期间的衰老进程,在贮藏14 d时,分别比对照高出22.30%、32.35%、36.67%,差异显著(P0.05);1-MCP还可减缓果实可滴定酸、维生素C等含量的下降,有助于保持果实的良好品质。1-MCP处理可抑制菠萝贮藏期的果实衰老进程,有利于保持果实品质,提高贮藏效果。研究结果将为菠萝贮藏保鲜措施提供参考。     

采收期结合1-MCP对苹果采后生理和贮藏品质的影响

为了探讨1-MCP处理对不同采收期‘维纳斯黄金’苹果的采后生理和贮藏品质的影响。研究了生长发育期为185 d（采收期Ⅰ）、192 d（采收期Ⅱ）、199 d（采收期Ⅲ）的3个采收期果实分别用浓度为0(CK)和1.0μL/L 1-MCP处理后,在常温（20±0.5）℃条件下采后生理和贮藏品质变化规律。结果表明,晚采果实的呼吸高峰和乙烯高峰较早采果实高,出现时间较早,与CK相比,1-MCP处理能显著降低3个采收期果实的乙烯释放速率和呼吸强度,明显抑制或延缓呼吸高峰和乙烯跃变高峰的出现时间。1-MCP处理对采收期Ⅰ和采收期Ⅲ果实的淀粉含量、淀粉酶活性与CK差异均不显著（P>0.05）,但1-MCP处理能保持3个采收期果实较高的硬度和原果胶含量、明显延缓可溶性果胶含量和PG酶（多聚半乳糖醛酸酶,Polygalacturonase）活性的上升,显著（P<0.05）抑制采收期Ⅱ果实贮藏13～25 d期间的淀粉酶活性上升,有效延缓淀粉转化。结果还表明,与采收期Ⅰ相比,采收期Ⅱ能维持‘维纳斯黄金’苹果较好的可溶性固形物、可滴定酸和维生素C等品质;与采收期Ⅲ相比,采收期Ⅱ能保持果实较高的硬度...     

生长调节剂处理对高州矮香蕉贮藏品质的影响

以高州矮香蕉为试材,研究了1-甲基环丙烯(1-MCP)和外源乙烯处理对香蕉贮藏品质的影响。结果表明,200nl/L 1-MCP处理可显著抑制香蕉可溶性糖和可溶性固形物含量上升,延缓果实硬度下降,从而延缓香蕉后熟进程;20μl/L外源乙烯对1-MCP处理果实的后熟进程影响不明显。     

1-MCP对冷藏花牛苹果生理活性及香气合成相关酶活性的影响

以花牛苹果为试材,研究了1-甲基环丙烯(1-MCP)处理对花牛苹果冷藏期间果实呼吸强度、乙烯释放速率及香气成分相关酶活性的影响。结果表明,1-MCP能够显著抑制冷藏期间花牛苹果果实呼吸强度和乙烯生成,推迟呼吸和乙烯释放高峰的出现,同时能够抑制花牛苹果香气合成的相关酶活性,从而延缓果实的后熟与衰老,有效保持花牛苹果贮藏期间的生理品质。冷藏120 d,果实LOX酶活性峰值较同期对照降低了21.6%;PDC酶活性于冷藏180 d时达到最大,较同期对照低了51.5%。1-MCP 处理降低了AAT酶活性峰值,但并未推迟峰值的来临。     

1-MCP和壳聚糖处理保持红枣贮藏品质及其机理研究

以新疆灰枣为试材,研究纸片型1-甲基环丙烯(1-methylcyclopropene,1-MCP)与壳聚糖(chitosan,COS)处理在(0±1)℃条件下对灰枣品质及相关酶活性的影响。结果表明:至贮藏90 d时,与对照(CK)相比,1-MCP+COS的腐烂率、失质量率分别降低53.4%、51.2%,可溶性固形物(total soluble solid, TSS)含量高出18.6%。抗氧化酶系统中的超氧化物歧化酶(superoxide dismutase, SOD)峰值水平提高58.2%,过氧化氢酶(catalase, CAT)峰值高出34.8%;贮藏结束时过氧化物酶(peroxidase, POD)活性是CK的1.98倍,抗坏血酸过氧化物酶(ascorbate peroxidase, APX)活性高出51.7%,差异显著(P0.05)。1-MCP、COS及1-MCP+COS处理均可不同程度地降低果实腐烂率、失质量率,保持较高的果实硬度和TSS含量,推迟呼吸高峰和乙烯释放速率高峰的到来并抑制丙二醛(malondialdehyde,MDA)的积累,抑制脂氧合酶(lipoxygenase, LOX)和多酚氧化酶(polyphenol oxidase, PPO)活性,显著提高抗氧化酶系统活性。其中1.50μL/L纸片型1-MCP与1%COS复合处理对保持果实贮藏品质、延缓果实衰老、延长货架期最有利。     

1-MCP和壳聚糖处理保持红枣贮藏品质及其机理研究

以新疆灰枣为试材,研究纸片型1-甲基环丙烯（1-methylcyclopropene,1-MCP）与壳聚糖（chitosan,COS）处理在（0±1）℃条件下对灰枣品质及相关酶活性的影响。结果表明：至贮藏90 d时,与对照（CK）相比,1-MCP＋COS的腐烂率、失质量率分别降低53.4%、51.2%,可溶性固形物（total soluble solid, TSS）含量高出18.6%。抗氧化酶系统中的超氧化物歧化酶（superoxide dismutase, SOD）峰值水平提高58.2%,过氧化氢酶（catalase, CAT）峰值高出34.8%;贮藏结束时过氧化物酶（peroxidase, POD）活性是CK的1.98倍,抗坏血酸过氧化物酶（ascorbate peroxidase, APX）活性高出51.7%,差异显著（P＜0.05）。1-MCP、COS及1-MCP+COS处理均可不同程度地降低果实腐烂率、失质量率,保持较高的果实硬度和TSS含量,推迟呼吸高峰和乙烯释放速率高峰的到来并抑制丙二醛（malondialdehyde, MDA）的积累,抑制脂氧合酶（lipoxygenase, LOX）和多酚氧化酶（polyphenol oxidase, PPO）活性,显著提高抗氧化酶系统活性。其中1.50 μL/L纸片型1-MCP与1% COS复合处理对保持果实贮藏品质、延缓果实衰老、延长货架期最有利。     

1-MCP乙烯受体阻断剂对香蕉果实采后生理和品质的影响

1-甲基环丙烯(1-MCP)可以显著延迟香蕉果实软化，但1-MCP对综合食用品质变化的影响不甚清楚。该试验以国产品种广东高州矮香蕉为试材，用200 nL/L 1-MCP处理24 h后贮藏于20℃条件下，分析了1-MCP对香蕉综合品质的影响。结果表明：1-MCP处理显著地降低了香蕉果肉中可溶性糖和可溶性固形物含量的上升速率，延缓了果实硬度的下降。1-MCP能延缓香蕉果实的后熟进程，但并不会降低香蕉的综合食用品质。即使外源乙烯的加入也不能加快1-MCP处理后香蕉果实的后熟进程。     

不同处理对猕猴桃采后生理和细胞超微结构的影响

为探索采后猕猴桃果实软化衰老机制及摔制途径,以"秦美"猕猴桃为试材,研究了1 μL/L1-MCP(1-甲基环丙烯)处理和1μmol/L NO处理对其采后生理和细胞超微结构的影响.结果表明:1-MCP处理与对照相比,极显著地抑制了果实的变软,对果实可溶性固形物含量的增加没有显著影响,使果实保持较高的POD活性,推迟SOD和POD活性高峰的出现,但对POD和SOD活性大小变化的影响不显著,明显延缓了果肉细胞壁的分解和叶绿体的解体,比对照在(0±1)℃的贮藏时间延长了12 w.NO处理与对照相比,对果实变软、果实可溶性固形物含量增加、SOD和POD的活性变化有显著影响,对果肉细胞壁的分解和叶绿体的解体有一定延缓效果,比对照延长贮藏时间28 d.1μL/L 1-MCP对秦美猕猴桃的保硬和保绿效果优于1 μmil/l NO.     

1-甲基环丙烯对根用芥菜贮藏品质及抗氧化性的影响

为解决根用芥菜贮藏期失重和发芽的问题，本研究以光头芥为试验材料，对照组不做处理，处理组采用1.0、1.5和2.0μL·L^-1 1-甲基环丙烯(1-MCP)进行熏蒸，探究不同浓度1-MCP处理对低温贮藏条件下根用芥菜贮藏品质及抗氧化性的影响。结果表明，1-MCP处理可提高根用芥菜的低温贮藏品质并促进其抗氧化作用。与对照相比，不同浓度1-MCP处理有效抑制了根用芥菜的呼吸强度，提高了贮藏品质及抗氧化作用，其中1.0μL·L^-1 1-MCP对根用芥菜的失重率、发芽率和木质素含量的抑制作用显著高于其他处理组(P<0.05);1-MCP处理保持了较高的硬度和抗坏血酸含量、延缓了根用芥菜细胞破损和丙二醛(MDA)含量积累、抑制了脂氧合酶(LOX)和苯丙氨酸解氨酶(PAL)活性、减缓了过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性下降、提高了超氧化物歧化酶(SOD)和过氧化物酶(POD)活性，其中1.0μL·L^-1 1-MCP效果最优。本研究结果为根用芥菜的贮藏保鲜提供了理论依据。     

1- MCP和60Co-γ辐照处理对自发气调包装大五星枇杷贮藏品质的影响

为研究1-甲基环丙烯(1-MCP)熏蒸和⁶⁰Co-γ辐照处理对枇杷贮藏品质的影响,本研究以大五星枇杷为试验材料,对采后自发气调包装枇杷的腐烂指数、木质素、硬度、呼吸强度、乙烯生成速率、相对电导率、可滴定酸(TA)、可溶性固形物(TSS)以及苯丙氨酸解氨酶(PAL)、脂氧合酶(LOX)、多酚氧化酶(PPO)、过氧化物酶(POD)活性进行测定,研究6±0.5℃条件下1 μL·L^-1 1-MCP、1.5 kGy⁶⁰Co-γ、1 μL·L^-1 1-MCP+1.5 kGy ⁶⁰Co-γ不同处理对枇杷贮藏品质的影响。结果表明, 1-MCP和⁶⁰Co-γ复合处理效果最好,可延缓腐烂指数和木质素含量上升,维持果实硬度,降低果实呼吸强度、乙烯生成速率和相对电导率,保持果实TA和TSS含量,抑制PAL、LOX、PPO和POD活性的上升。在贮藏40 d时,1-MCP和⁶⁰Co-γ复合处理枇杷的腐烂指数仅为17.95%,而1-MCP组、⁶⁰Co-γ组、CK组分别为22.86%、25.72%和36.24%。因此,1-MCP和⁶⁰Co-γ复合处理对枇杷果实的贮藏效果最好。本研究结果为枇杷的贮藏保鲜提供了理论依据。     

1-MCP复合杀菌剂对西州蜜甜瓜常温贮藏品质的影响

为了探究不同保鲜剂复合杀菌剂对甜瓜的保鲜效果,以西州蜜甜瓜为试验材料,研究了抑霉唑硫酸盐、ClO₂、咪鲜胺、1-MCP、1-MCP复合抑霉唑硫酸盐和无菌水对甜瓜常温贮藏下品质的影响。结果表明,与对照无菌水相比,所有保鲜剂均可显著抑制甜瓜采后腐烂与失重,维持果实硬度和可溶性固形物含量,提升贮藏品质。1-MCP与1-MCP复合杀菌剂处理可显著抑制西州蜜果实的呼吸速率和乙烯释放速率,呼吸峰值较对照无菌水分别降低43.7%和37.5%,乙烯释放峰值较对照无菌水分别降低47.9%和53.7%,呼吸峰值和乙烯释放峰值出现时间均推迟3 d。其中1-MCP复合杀菌剂对果实可滴定酸和Vc含量保持效果显著,与对照无菌水相比,可滴定酸含量提高40.0%,Vc含量提高38.2%,对西州蜜甜瓜的保鲜效果最好。     

Relationships between respiration, ethylene, and aroma production in ripening banana

Mature green bananas were treated with the ethylene antagonist 1-methylcyclopropene (1-MCP) at intervals during the 24 h period after initiation of ripening with propylene. Following 1-MCP treatment, the fruits were ripened in either air or propylene while ethylene, carbon dioxide, and volatile production and composition were monitored at regular intervals. The application of 1-MCP significantly delayed and suppressed the onset and magnitude of fruit respiration and volatile production. The 1-MCP treatments also caused a quantitative change in the composition of the aroma volatiles, resulting in a substantial increase in the concentration of alcohols and a decrease in their related esters. The results showed that ethylene has a continuing role in integrating many of the biochemical processes that take place during the ripening of bananas.     

Influence of 1-methylcyclopropene on ripening,storage life,and volatile production by d'Anjou cv. pear fruit

d'Anjou cv. pear fruit (Pyrus communis L.) exposed at harvest to 0, 0.42, 4.2, or 42 micromol m(-)(3) 1-methylcyclopropene (1-MCP) for 12 h at 20 degrees C were stored at 1 degrees C for up to 8 months. After storage, half of the fruit was continuously exposed to ethylene (0.45 or 4-18 mmol m(-)(3)) for 7 days at 20 degrees C. All fruit treated with 1-MCP had lower respiration and ethylene production compared to untreated controls. Fruit quality changes were delayed following 1-MCP treatment, as was development of superficial scald and peel yellowing. The duration of 1-MCP-induced responses was dependent on 1-MCP treatment concentration. When 1-MCP-treated fruit began to ripen, softening and production of volatile compounds proceeded similar to that of untreated fruit. Post-storage ethylene exposure did not consistently stimulate ripening of fruit previously treated with 1-MCP. Efficacy of ethylene treatment depended on 1-MCP concentration and storage duration.     

1-Methylcyclopropene interactions with diphenylamine on diphenylamine degradation, alpha-farnesene and conjugated trienol concentrations, and polyphenol oxidase and peroxidase activities in apple fruit

1-Methylcyclopropene (1-MCP) is a new technology that is applied commercially to inhibit ethylene action in apple fruit, but its interactions with existing technologies such as diphenylamine (DPA) for control of superficial scald development in fruit during and after storage is unknown. To investigate possible interactions between 1-MCP and DPA, Delicious apples were untreated or treated with 2 g L(-1) DPA, and then with or without 1 microL L(-1) 1-MCP. Ethylene production and respiration rates of fruit were measured immediately following treatment, and fruit was stored at 0.5 degrees C for 12 weeks. Internal ethylene concentrations (IEC), alpha-farnesene and conjugated trienol (CTol) concentrations, activities of peroxidase and polyphenol oxidase (PPO), and DPA levels in the skin of the fruit were measured at intervals during storage. 1-MCP reduced the rate of DPA loss from peel tissue so that by 12 weeks of storage concentrations of the chemical were 25% higher than in untreated fruit. 1-MCP, with and without DPA, markedly inhibited ethylene production and respiration rates, maintained low IEC and alpha-farnesene and CTol concentrations, while DPA had little effect on these factors except inhibition of CTol accumulation. Treatment effects on peroxidase and PPO activities were inconsistent.     

高压静电场处理对红元帅苹果采后品质的影响

该研究利用自制的高压静电场保鲜实验台产生的-50 kV/m和-100 kV/m高压静电场处理红元帅苹果，贮藏过程中每4d测定1次果实呼吸强度、内源乙烯释放量、果实硬度和可溶性固形物含量变化，并在贮藏结束时，对果实品质进行感官评定。实验结果表明：高压静电场处理使红元帅苹果的乙烯释放高峰推迟4 d，乙烯释放高峰值显著低于对照，并且使果实呼吸跃变推迟8 d。高压静电场处理苹果，在20℃条件下贮藏24 d，果实硬度和可溶性固形物含量显著高于对照，果实新鲜程度、脆性、硬度、粉性、甜味和苹果味等感官指标显著比对照好（p<0.01)，表明高压静电场处理对保持红元帅苹果的采后品质具有显著作用。     

不同采收期对苹果常温贮藏品质和衰老的影响

以通辽地区的‘塞外红’苹果为试材,研究了生长发育期在116~134 d内的3个采收期果实常温(20±1)℃贮藏品质和软化衰老的变化,以确定‘塞外红’苹果的最佳采收成熟度和适宜采收期。结果表明,随着采收期的推迟,果实硬度逐渐降低,可溶性固形物和可滴定酸含量逐渐升高,种子颜色逐渐变褐到全褐。随着贮藏时间的延长,3个采收期果实的硬度、维生素C和可滴定酸含量均逐渐下降,从采收到贮藏结束,采期Ⅰ果实的硬度一直保持最高,采期Ⅱ保持了果实较高的维生素C和可滴定酸含量,采期Ⅲ果实的可溶性固形物含量SSC一直保持最高。结果还表明,采期Ⅰ的果实常温贮藏期间虽然具有较高的原果胶和纤维素含量,而且抑制了可溶性果胶的生成,推迟了果实多聚半乳糖醛酸酶PG活性和纤维素酶活性高峰,延缓了果实呼吸高峰和乙烯释放高峰的出现时间,但果实的外观色泽、口感和风味相对较差;采期Ⅲ的果实丙二醛和乙醇含量积累较多,果实衰老快。综合分析,采期Ⅱ的‘塞外红’苹果具有良好的内在品质、外观色泽和贮运性能。因此,建议通辽地区‘塞外红’苹果的采收期以9月5—10日为宜(可适当晚采1~2 d),采收成熟度参考标准为:果实生长发育天数123~128 d、果肉硬度11.0~11.5 kg/cm^2、SSC≥16.5%、种子的颜色3/4左右变褐、淀粉染色为4.5级左右。     

Impact of suppression of ethylene action or biosynthesis on flavor metabolites in apple (Malus domestica Borkh) fruits

To understand the role of ethylene in regulating the overall flavor of apple fruits, ethylene production or action was reduced using transgenic apple trees suppressed for ACC-synthase or ACC-oxidase enzyme activity or by the addition of 1-methylcyclopropene (1-MCP), an ethylene action inhibitor. Flavor components were differentially regulated in response to the suppression of both ethylene biosynthesis and action. Headspace analysis of aroma production, an ethylene-associated event, showed a reduction in ester and alcohol production in the ethylene-suppressed lines and in the apples treated with 1 microL L(-1) 1-MCP for 20 h at 20 degrees C. However, no major differences were observed in the concentrations of aldehyde volatiles. Other flavor metabolites that showed an ethylene-dependent pattern were organic acids and sugars. Malic acid degradation was significantly reduced under ethylene-suppressed conditions, showing a recovery after the fruit was exposed to ethylene. Sucrose and fructose concentrations were influenced by suppression or enhancement of ethylene. Total phenolics as well as individual phenolic compounds showed an ethylene-dependent regulation only in response to the suppression of ethylene biosynthesis, but not when ethylene action was inhibited.