低温贮藏能有效降低采后果蔬生理代谢活动、营养物质消耗、微生物侵染等,从而提高果蔬品质、延长贮藏期。然而,冷敏型果蔬对低温十分敏感,在低温下长期贮藏或在不适宜的低温下贮藏均会发生生理代谢障碍和伤害,最终表现为果蔬出现冷害症状,这大大降低了果蔬商品价值,造成巨大的经济损失。
采用外源化学物质处理能有效降低采后果蔬冷害的发生[1-2]。褪黑素(melatonin),又名N-乙酰-5-甲氧基色胺,是一种广泛分布在生物体内的吲哚胺类化合物,能在果蔬贮藏保鲜中发挥多种生理功能延缓其成熟衰老进程,是一种天然、高效、安全的化学保鲜剂[3]。褪黑素能延缓采后果蔬硬度下降[4]、促进抗坏血酸、花青素等抗氧化物质积累[5-6]、增加香气成分[7]、减少异味产生[8]、减轻黄化[9]和褐变发生[10]、抑制开伞[11]等,从而提高采后果蔬贮藏品质。越来越多的文献资料显示,褪黑素能提高果蔬低温贮藏下抗冷性,降低果蔬冷害的发生[12]。本文主要从果蔬细胞膜结构和功能、抗氧化能力、能量代谢、脯氨酸代谢、糖代谢等5个方面来综述褪黑素处理减轻果蔬冷害的机理,并分析了影响褪黑素减轻采后果蔬冷害的因素,以期为褪黑素减轻采后果蔬冷害提供理论依据。
1 褪黑素处理对采后果蔬冷害症状的影响
采后果蔬发生冷害主要表现为果皮或果肉褐变、果皮水渍状斑点或凹陷斑、果实硬度不正常增加、果实不能正常后熟软化、果实表面失去光泽、果蔬抗病性减弱等,这严重影响了果蔬的贮藏品质。表1列出了褪黑素处理浓度对各种果蔬冷害症状的影响。千春录[13]、CAO[14]、SHARAFI[15]、JANNATIZADEH[16]、何欢[17]、DU[18]等采用100 μmol/L褪黑素处理能有效减轻桃、甜樱桃、石榴、杏、李子等果实果肉褐变的冷害症状。胡苗等[19]采用100 μmol/L褪黑素处理能有效减轻猕猴桃果肉木质化的冷害症状。WANG等[20]和CHEN等[4]采用褪黑素处理能减轻香蕉、番石榴果皮褐变的冷害症状。LIU等[21]和WANG等[22]采用400 μmol/L褪黑素处理能减轻荔枝果皮褐变的冷害症状。KONG等[23]采用100 μmol/L褪黑素处理能减轻青椒果实斑点和果柄褐变的冷害发生。KEBBEH等[24]、BHARDWAJ等[25]、ALI等[26]、MADEBO等[27]采用100 μmol/L褪黑素处理能减轻芒果、西葫芦、黄瓜果实表皮褐变、凹陷、水渍状斑点等冷害症状,减轻冷害发生。由此可见,褪黑素对于减轻采后果蔬冷害症状具有较好效果。
表1 褪黑素处理浓度对果蔬冷害症状的影响
Table 1 Effects of melatonin treatment concentration on symptom of chilling injury of fruits and vegetables
序号处理浓度/(μmol/L)处理材料研究结果文献来源1100番石榴减轻果皮褐变及表面凹陷斑[4]2100黄瓜减轻黄瓜表皮出现的凹陷斑、水浸状斑点,减轻致病菌侵染冷害斑而出现腐烂[27]3100李子降低果肉褐变[18]4100芒果降低芒果果皮褐变、凹陷 [24-25]5100猕猴桃抑制猕猴桃果实木质素含量上升,延迟果实冷害发生时间[19]6100青椒减轻青椒果实斑点和青椒柄褐变[23]7100石榴降低石榴果皮褐变[16]8100桃抑制桃果实褐变[13-14]9100西葫芦减轻果实表皮凹陷斑、水渍状斑点,降低黄化和腐烂程度,延迟冷害症状的出现[26]10100杏降低杏果实褐变[17]11100樱桃降低果肉褐变和腐烂[15]12200香蕉减轻香蕉果皮褐变[20]13400荔枝抑制荔枝果皮变色,提高L∗值和花青素水平[21-22]
2 褪黑素处理对采后果蔬冷害症状的影响
2.1 褪黑素处理能维持采后果蔬细胞膜结构和功能
细胞膜是细胞生命活动的基础,采后果蔬细胞膜在低温胁迫下由液晶态转变为凝胶态,流动性变差、通透性增加,细胞膜结构和功能被破坏,细胞内电解质外渗,加剧果蔬冷害发生。表1列出了褪黑素处理对采后果蔬细胞膜的影响及其与冷害的关系。最早LEI等[28]研究发现,褪黑素可保持低温胁迫下胡萝卜悬浮细胞膜的完整性。WANG等[22]、贾乐[11]、苗萌[29]认为褪黑素处理能够抑制采后荔枝、香菇、苹果果实膜脂过氧化反应,维持其细胞膜结构和功能完整,提高其贮藏品质。丙二醛是果蔬细胞膜脂过氧化产物,其含量与果蔬冷害程度密切相关。JANNATIZADEH等[16]、KONG等[23]发现褪黑素处理能显著降低采后石榴、辣椒等丙二醛和H2O2积累,保持细胞膜完整性,减轻冷害发生。王锋等[30]将褪黑素与壳聚糖、ZnO制备成复合涂膜剂处理黄瓜果实,发现该复合处理能使黄瓜丙二醛含量维持在较低水平,减轻膜脂过氧化程度,降低冷害发生。由此可见,褪黑素能降低采后果蔬膜脂过氧化反应,维持细胞膜完整性,从而减轻冷害发生。
磷脂酶D和脂氧合酶是果蔬中参与细胞膜脂质降解的主要脂质氧化酶,它们能降解采后果蔬细胞膜组成成分,破坏细胞膜结构的完整,与果蔬冷害发生密切相关。吕麟琳等[31]认为,1-甲基环丙烯能显著抑制香蕉李果实磷脂组分降解,保持较高的总磷脂含量,维持细胞膜结构的稳定,降低了冷害的发生。孔祥佳等[32]采用热空气处理可降低采后橄榄果实脂氧合酶活性,减少膜脂不饱和脂肪酸降解,维持细胞膜较好的结构和完整性,减轻冷害发生。WANG等[22]研究认为,褪黑素处理减轻荔枝冷害发生与其显著抑制荔枝果实磷脂酶D、脂肪酶和脂氧合酶的活性阻止磷脂酰胆碱水解有关。由此可见,抑制采后果蔬细胞膜组成成分的降解有利于减轻采后果蔬冷害的发生。果蔬细胞膜脂脂肪酸的组成包括不饱和脂肪酸(主要是油酸、亚油酸、亚麻酸等)和饱和脂肪酸(主要是棕榈酸和硬脂酸),其中不饱和脂肪酸的含量影响细胞膜的流动性,从而影响采后果蔬的冷害。果蔬细胞膜不饱和脂肪酸所占的比例越高,细胞膜的流动性越好,果蔬耐冷性也越强,果实发生冷害程度也越低[32-33]。CAO等[14]、WANG等[20]和BHARDWAJ等[25]发现,采用褪黑素处理桃、香蕉和芒果果实能维持果实较高的不饱和脂肪酸含量,减轻冷害发生。KONG等[23]研究表明,褪黑素处理甜椒能增加亚油酸与亚麻酸的比例,提高不饱和脂肪酸与饱和脂肪酸的比值,减少细胞膜结构损伤,缓解冷害发生。WANG等[22]采用褪黑素处理能维持采后荔枝较高的油酸、亚油酸、亚麻酸含量和较低的棕榈酸、硬脂酸含量,降低细胞膜通透性变化,减轻冷害发生。因此,褪黑素处理能维持果蔬细胞膜的结构和功能,有利于减轻果蔬冷害的发生。
2.2 褪黑素处理能提高采后果蔬抗氧化能力
采后果蔬在低温逆境胁迫下会产生大量活性氧,打破果蔬体内自由基生成和清除的动态平衡,引发膜脂过氧化反应,破坏细胞膜结构,导致果蔬冷害发生[34]。果蔬体内酶促和非酶促抗氧化系统的激活能提高果蔬抗氧化能力,清除过多的活性氧,降低果蔬细胞氧化伤害,减轻冷害发生。不同浓度的褪黑素处理能显著提高采后果蔬体内总酚、类黄酮、花色苷等抗氧化物质含量,增强超氧化物歧化酶(superoxide dismutase, SOD)、抗坏血酸过氧化物酶(ascorbate peroxidase,APX)、过氧化物酶(peroxidase, POD)、过氧化氢酶(catalase, CAT)、谷胱甘肽还原酶(glutathione reductase,GR)等抗氧化酶活性,提高果蔬抗氧化能力,延缓果蔬的衰老进程[35]。贾乐[11]、苗萌[29]研究认为,褪黑素处理可降低采后果蔬超氧阴离子生成速率及羟自由基生成能力,有助于清除果蔬体内活性氧。GAO等[36]认为褪黑素能提高镉胁迫下蘑菇体内SOD、CAT、POD活性及基因表达,对于镉诱导的氧化具有保护作用。SHARAFI等[15]研究认为,褪黑素处理能提高甜樱桃体内SOD、APX、POD、CAT等活性,增强酚类、类黄酮和花青素的积累,提高抗氧化能力。朱玲玲[37]发现,褪黑素处理提高青花菜抗氧化酶活性是由于提高了同工酶SODⅠ、SODⅡ、SODⅢ、PODⅠ、PODⅡ和CAT的活性。王蕾[38]发现褪黑素提高葡萄抗氧化酶活性与其在蛋白水平上提高SOD、POD、APX等抗氧化酶表达量有关。越来越多的研究表明,褪黑素减轻采后果蔬冷害的发生与诱导提高抗氧化能力有关[39]。胡苗[19]研究发现,褪黑素处理能显著提高猕猴桃果实0 ℃低温贮藏期间SOD、CAT、APX、GR等抗氧化酶活性,延缓果蔬后熟和衰老。RASTEGAR等[5]、ALI等[26]认为褪黑素处理降低石榴、西葫芦果实冷害发生与提高CAT、APX、POD和SOD活性有关。CAO等[14]研究表明,褪黑素处理上调了桃果实中参与抗氧化反应抗坏血酸-谷胱甘肽循环基因的表达,提升了抗坏血酸含量,增强了桃果实对冷胁迫的抗性。KONG等[23]研究认为,褪黑素处理能上调青椒CaSOD、CaPOD、CaCAT和CaAPX基因的转录水平而提高抗氧化能力,减轻冷害发生。SHANG等[40]认为褪黑素处理能提高蓝莓抗坏血酸、花青素和总酚含量,促进APX等抗氧化酶活性,诱导抗氧化基因VcAPX、VcGST和VcPAL表达量上调,提高了活性氧自由基清除能力,延缓冷害发生。因而,褪黑素处理减轻采后果蔬的冷害与抗氧化酶活性及基因表达、抗氧化物质含量有关。
2.3 褪黑素处理能调节采后果蔬能量代谢
果蔬的正常代谢过程需要能量来维持,很多文献表明褪黑素处理能提高采后果蔬能量代谢而提高果蔬贮藏品质[25,41]。TAN等[9]认为褪黑素处理能激活三磷酸腺苷酶和烟酰胺腺嘌呤二核苷酸激酶活性,导致大白菜三磷酸腺苷(adenosine triphosphate,ATP)和二磷酸腺苷(adenosine diphosphate,ADP)含量升高,保持较高的能量状态和能荷水平,延缓大白菜叶片黄化进程。朱玲玲等[37]发现褪黑素处理维持采后青花菜较高ATP、ADP及能荷水平与其显著降低糖酵解、三羧酸循环和磷酸戊糖呼吸途径的运行比例,提高交替氧化途径的运行比例有关。LI等[42]认为褪黑素处理保持双孢蘑菇较高ATP水平与提高复合物Ⅰ和Ⅲ活性,提高线粒体氧化磷酸化和效率有关。
低温胁迫下果蔬受到低温伤害会积累活性氧导致氧化损伤,阻碍能量合成的进程,引发能量供给不足,导致冷害发生。充足的能量供应有助于减轻果蔬低温胁迫伤害,降低果蔬冷害发生[43]。琥珀酸脱氢酶(succinate dehydrogenase,SDH)、细胞色素C氧化酶(cytochrome c oxidase,CCO)、H+-ATPase和Ca2+-ATPase是采后果蔬能量产生的重要酶类,提高这些酶活性能提高采后果蔬ATP供应和能荷水平,有利于减轻冷害发生[44]。DONG等[41]认为褪黑素处理能调节刺梨能量代谢,提高ATP和ADP含量而维持较好品质。JANNATIZADEH等[16]、LIU等[21]、BHARDWAJ等[25]采用褪黑素处理番茄、荔枝、芒果果实均能显著提高SDH、CCO、H+-ATPase和Ca2+-ATPase活性,增加ATP、ADP含量和能荷,保证细胞内能量供应,减轻果实冷害发生。WANG等[22]采用褪黑素处理荔枝果皮也得到了类似结果。由此可见,褪黑素可通过调控采后果蔬的能量代谢减轻采后果蔬冷害的发生。
2.4 褪黑素处理能调节采后果蔬脯氨酸代谢
脯氨酸是果蔬体内重要的渗透调节物质,能够响应采后果蔬的低温胁迫,果蔬体内脯氨酸含量与果蔬冷害密切相关[45]。ALI等[26]认为提高果蔬脯氨酸含量能增加果蔬低温耐受性,降低果蔬冷害。采用褪黑素处理桃[46]、南果梨[47]、黄瓜[27]、甜椒[23]等均能提高果蔬中脯氨酸含量,减轻冷害发生。1-吡咯琳-5-羧酸合成酶(delta-1-pyrroline-5-carboxylate synthase,P5CS)和鸟氨酸转移酶(ornithine amino transferase,OAT)是脯氨酸合成代谢过程中关键酶,脯氨酸脱氢酶(proline dehydrogenase,PDH)是脯氨酸分解代谢过程中关键酶[45],提高果蔬中P5CS和OAT活性,降低PDH活性,能维持果蔬较高脯氨酸含量,降低冷害发生,这在精氨酸处理木瓜[48]、茉莉酸甲酯处理枇杷[49]、丁香酚熏蒸处理青茄[50]的研究中已得到证实。ALI等[26]采用褪黑素处理西葫芦也得到了类似的结果。SUN等[47]、MADEBO等[27]、KEBBEH等[24]进一步研究表明,褪黑素处理提高果蔬脯氨酸含量与诱导提高OAT和P5CS基因的表达、降低PDH基因表达有关。AGHDAM等[51]认为褪黑素处理可上调番茄果实ZAT2/6/12基因表达,通过触发精氨酸通路活性而促进脯氨酸等物质积累,增强了番茄果实抗冷性。表2列出了褪黑素处理浓度对采后果蔬脯氨酸代谢的影响及其与冷害的关系,说明了褪黑素处理降低采后果蔬冷害的发生与脯氨酸代谢有关。
表2 褪黑素处理浓度对果蔬脯氨酸代谢的影响及其与冷害的关系
Table 2 Effects of melatonin treatment concentration on proline metabolism of fruits and vegetables and its relationship with chilling injury
序号处理浓度/(μmol/L)处理材料研究结果文献来源1100番茄上调ZAT2/6/12基因表达,通过触发精氨酸通路活性促进内源脯氨酸、多胺和NO积累,从而增强番茄果实抗冷性[51]2100黄瓜显著提高P5CS和OAT活性,抑制PDH活性,诱导CsOAT和CsP5CS基因表达,脯氨酸含量增加,增强黄瓜的抗冷性[27]3100梨促进P5CS和OAT活性,刺激脯氨酸积累,提高抗氧化能力,维护细胞膜完整性,提高抗冷性[47]4100芒果显著增加脯氨酸含量,降低芒果冷害发生。这些变化伴随着脯氨酸生物合成关键酶活性及其编码基因表达的增加,包括P5CS、P5CR、OAT、P5CS2、P5CR2和OAT3。同时,经褪黑素处理后芒果的PDH活性和PDH3表达量低于对照。褪黑素可调控脯氨酸代谢有助于增强芒果抗冷性[24]5100桃上调PpADC和PpODC基因表达和转录水平,抑制PpPDH表达,提升桃果脯氨酸含量,减轻冷害[46]6100甜椒增加甜椒脯氨酸含量,减轻冷害发生[23]7200西葫芦增加P5CS和OAT活性,降低PDH活性,增加脯氨酸积累,降低冷害发生[26]
2.5 褪黑素处理能调节采后果蔬糖代谢
褪黑素具有调节糖代谢的作用,可提高果实品质。刘建龙[52]研究发现,100 μmol/L褪黑素处理可提高早酥梨可溶性糖的含量,特别是蔗糖和山梨醇。胡容平等[53]研究得到150 μmol/L褪黑素处理能使葡萄中与蔗糖代谢相关的分解酶类活性高于合成酶类活性,促进蔗糖分解代谢,葡萄糖和果糖大量积累,提升葡萄果实品质。TAN等[9]认为100 μmol/L褪黑素处理能提高大白菜叶片可溶性糖含量,这与其调节葡萄糖-6-磷酸脱氢酶和6-磷酸葡萄糖酸脱氢酶活性上升有关。XIA等[6]和FAN[54]研究表明,褪黑素处理能提高葡萄和苹果果实可溶性糖含量,这主要是其抑制果实酸性转化酶和中性转化酶活性、增加蔗糖合成酶和蔗糖磷酸合成酶活性的结果。刘建龙[52]采用褪黑素处理梨果实也得出类似结论。采后果蔬糖代谢与冷害的发生密切相关,低温胁迫下果蔬中糖类物质可通过参与调节渗透压、稳定细胞膜、抗氧化等提高果蔬对低温胁迫的抵抗力,降低冷害发生。陈克明等[55]认为桃果实采后低温贮藏期间果糖损失可能是加剧果实冷害发生的重要原因。采用茉莉酸甲酯处理桃果实能显著增加可溶性糖含量,提高果实耐冷性,减少冷害发生[56]。ZHAO等[57]研究发现,近冰温贮藏能显著降低油桃果实蔗糖代谢相关酶活性,维持较高的己糖激酶和果糖激酶活性,减轻油桃果实冷害发生。吴雪霞等[58]研究表明,褪黑素处理可显著提高茄子幼苗蔗糖合成酶活性,降低酸性转化酶、中性转化酶和蔗糖磷酸合成酶活性,提高茄子幼苗可溶性糖、蔗糖、果糖含量,提高逆境胁迫能力。徐利伟等[59]研究发现,褪黑素处理能抑制桃果实蔗糖代谢相关酶基因PpSPS3、PpSPP1、PpSUS1、PpSUS5、PpHK1、PpFK1和PpFK3的表达,提高蔗糖合成相关酶基因PpSPS1、PpSPS2、PpSUT1和PpNI1的表达水平,维持桃果实较高的蔗糖和葡萄糖含量,提高桃的抗冷性,减轻冷害症状。由此可见,褪黑素处理能调节低温下采后果蔬糖代谢也是其减轻冷害的原因之一。
3 影响褪黑素处理减轻采后果蔬冷害的因素
3.1 果蔬种类
果蔬种类不同则褪黑素处理对其冷害的控制效应也不同。对于桃[13]、杏[17]、李[18]、芒果[24-25]、青椒[23]、西葫芦[26]等冷敏型果蔬,褪黑素处理能降低果蔬果皮和果肉褐变、抑制果皮凹陷、水渍状斑点的形成,减轻冷害发生。对于猕猴桃[19]等褪黑素则能抑制木质素升高,降低其冷害发生时的木质化程度。对于大白菜[9]、黄瓜[27]等含叶绿素的果蔬,褪黑素能抑制其叶绿素降解,减轻果蔬黄化发生。由此可见,褪黑素处理控制采后果蔬冷害发生的表现不尽相同,这与果蔬种类不同有关。
3.2 处理浓度
褪黑素浓度是影响采后果蔬冷害控制效应的重要因素,褪黑素处理浓度不同对采后果蔬冷害的缓解效应不同。很多研究认为控制采后果蔬较为理想的褪黑素处理浓度为100 μmol/L,这在采后桃[13-14]、石榴[16]、杏[17]、李子[18]、芒果[23-24]、青椒[23]、西葫芦[26]、黄瓜[27]等果实中已得到证实。然而减轻香蕉[20]、荔枝[21-22]果实冷害的最适宜褪黑素处理浓度却分别为200和400 μmol/L,这说明果蔬种类不同控制其冷害发生的最适宜褪黑素处理浓度也不同。
3.3 与其他冷害控制措施的联用
多种保鲜措施联用能增强其对采后果蔬保鲜效果,提高贮藏品质[60-61]。很多文献资料也表明,褪黑素与其他冷害控制措施联用会协同增加其对果蔬冷害的控制效应,减轻冷害发生。例如,朱芹[62]发现褪黑素联合热处理对水蜜桃冷害抑制效果最好,贮藏(35+3) d时对照组、热处理组、褪黑素处理组水蜜桃冷害指数分别比联合处理组提高27%、16.3%和12.7%。骆思铭[63]研究表明,褪黑素复合甜菜碱处理能更好地控制黄瓜冷害症状,处理组黄瓜冷害指数比对照组低36%。LIN等[64]研究认为,褪黑素联合乙醇处理对于减轻苦瓜冷害症状更有效,且能将苦瓜冷害症状延迟4 d出现。MEDINA-SANTAMARINA等[65]认为褪黑素和1-MCP联用能协同增加西葫芦的耐冷性,西葫芦贮藏9 d后仍然表现出较高耐冷性。JIAO等[66]也研究发现,采用褪黑素联合1-甲基环丙烯处理能降低甜柿冷害,复合处理的甜柿低温贮藏70 d后,其冷害指数分别比褪黑素、1-MCP单独处理降低89.77%和61.98%。由此可见,将褪黑素和其他冷害控制措施联用对于降低采后果蔬冷害发生更为有效。
4 结论
综上所述,褪黑素作为一种新型果蔬保鲜剂,具有安全、高效、环境友好等优点,对果蔬采后贮藏过程中冷害的发生具有调控作用,应用前景广阔。褪黑素能够维持细胞膜结构和功能、诱导提高果蔬的抗氧化能力、增强果蔬脯氨酸代谢、能量代谢及糖代谢等而降低果蔬冷害的发生。虽然褪黑素减轻采后果蔬冷害已有一定的研究,但还处于初级阶段,研究尚不深入,建议未来可从以下方面开展深入研究:
(a)大多数文献报道的是褪黑素单独使用对果蔬冷害的调控作用,虽然在一定程度上能减轻果蔬冷害的发生,但是整体调控效果不尽如人意,不能同时解决采后果蔬低温贮藏中冷害、褐变、腐烂等多种问题,且大多数研究只是在实验室条件下的研究,并没有进行推广和使用。很多资料表明复合处理可激活采后果蔬体内多种抗冷防御机制,增强果蔬抗冷性,明显提高果蔬冷害的防控效果。今后应着重考虑将物理、化学、生物等多种技术与褪黑素处理相结合,充分发挥其协同效应,增强其对果蔬冷害的调控效果,开发出适合生产实际、能大规模应用的果蔬冷害防控新技术,这是今后研究的重要方向。
(b)目前研究主要集中在褪黑素对采后果蔬冷害相关指标调控的生理层面,对于分子层面上的机理研究报道较少,尤其是褪黑素介导采后果蔬低温胁迫的应答机制、果蔬响应褪黑素的耐冷相关基因挖掘、褪黑素与果蔬体内信号分子之间相互作用机制、褪黑素介导果蔬低温胁迫下信号传导等方面鲜有研究。随着现代研究技术的不断创新,转录组学、代谢组学和蛋白组学越来越广泛地应用于果蔬冷害分子机制的研究,后续可通过多组学技术相结合深入研究褪黑素降低采后果蔬冷害发生的关键代谢通路、信号传导途径、关键调控基因等,进一步从分子层面深入揭示褪黑素降低采后果蔬冷害的机制。
[1] LUKATKIN A, 
A, BOBINAS 
, et al.Chilling injury in chilling-sensitive plants:A review[J].Zemdirbyste-agriculture, 2012, 99:111-124.
[2] ZHANG W L, JIANG H T, CAO J K, et al.Advances in biochemical mechanisms and control technologies to treat chilling injury in postharvest fruits and vegetables[J].Trends in Food Science &Technology, 2021, 113:355-365.
[3] WANG S Y, SHI X C, WANG R, et al.Melatonin in fruit production and postharvest preservation:A review[J].Food Chemistry, 2020, 320:126642.
[4] CHEN H B, LIN H T, JIANG X J, et al.Amelioration of chilling injury and enhancement of quality maintenance in cold-stored guava fruit by melatonin treatment[J].Food Chemistry:X, 2022, 14:100297.
[5] RASTEGAR S, HASSANZADEH KHANKAHDANI H, RAHIMZADEH M.Effects of melatonin treatment on the biochemical changes and antioxidant enzyme activity of mango fruit during storage[J].Scientia Horticulturae, 2020, 259:108835.
[6] XIA H, SHEN Y Q, DENG H H, et al.Melatonin application improves berry coloration, sucrose synthesis, and nutrient absorption in ‘Summer Black’ grape[J].Food Chemistry, 2021, 356:129713.
[7] 杜天浩, 周小婷, 朱兰英, 等.褪黑素处理对盐胁迫下番茄果实品质及挥发性物质的影响[J].食品科学, 2016, 37(15):69-76.DU T H, ZHOU X T, ZHU L Y, et al.Effect of melatonin treatment on tomato fruit quality and volatile compounds under salt stress[J].Food Science, 2016, 37(15):69-76.
[8] 王晶, 洪敏, 冯雨, 等.外源褪黑素对‘爱媛38号’柑橘品质和乙醇代谢的影响[J].食品与发酵工业, 2019, 45(21):147-154.WANG J, HONG M, FENG Y, et al.Effects of exogenous melatonin treatment on fruit quality and ethanol metabolism of ‘Aiyuan 38’ Citrus[J].Food and Fermentation Industries, 2019, 45(21):147-154.
[9] TAN X L, FAN Z Q, ZENG Z X, et al.Exogenous melatonin maintains leaf quality of postharvest Chinese flowering cabbage by modulating respiratory metabolism and energy status[J].Postharvest Biology and Technology, 2021, 177:111524
[10] GAO H, LU Z M, YANG Y, et al.Melatonin treatment reduces chilling injury in peach fruit through its regulation of membrane fatty acid contents and phenolic metabolism[J].Food Chemistry, 2018, 245:659-666.
[11] 贾乐. 褪黑素处理对香菇采后自溶的影响及转录组分析[D].金华:浙江师范大学, 2021.JIA L.Effect of melatonin treatment on postharvest autolysis of lentinus edodes and transcriptome analysis[D].Jinhua:Zhejiang Normal University, 2021.
[12] ZE Y, GAO H J, LI T T, et al.Insights into the roles of melatonin in maintaining quality and extending shelf life of postharvest fruits[J].Trends in Food Science &Technology, 2021, 109:569-578.
[13] 千春录, 朱芹, 高姗, 等.外源褪黑素处理对采后水蜜桃冷藏品质及冷害发生的影响[J].江苏农业学报, 2020, 36(3):702-708.QIAN C L, ZHU Q, GAO S, et al.Effects of exogenous melatonin treatment on cold storage quality and chilling injury of postharvest peach fruit[J].Jiangsu Journal of Agricultural Sciences, 2020, 36(3):702-708.
[14] CAO S F, SHAO J R, SHI L Y, et al.Melatonin increases chilling tolerance in postharvest peach fruit by alleviating oxidative damage[J].Scientific Reports, 2018, 8(1):806.
[15] SHARAFI Y, JANNATIZADEH A, FARD J R, et al.Melatonin treatment delays senescence and improves antioxidant potential of sweet cherry fruits during cold storage[J].Scientia Horticulturae, 2021, 288:110304.
[16] JANNATIZADEH A.Exogenous melatonin applying confers chilling tolerance in pomegranate fruit during cold storage[J].Scientia Horticulturae, 2019, 246:544-549.
[17] 何欢, 刘昭雪, 张亚琳, 等.外源褪黑素通过调控活性氧代谢减轻采后杏果实冷害[J].食品科学, 2022, 43(5):168-174.HE H, LIU Z X, ZHANG Y L, et al.Exogenous melatonin ameliorates postharvest chilling injury of apricot fruit by modulating reactive oxygen species metabolism[J].Food Science, 2022, 43(5):168-174.
[18] DU H Y, LIU G T, HUA C M, et al.Exogenous melatonin alleviated chilling injury in harvested plum fruit via affecting the levels of polyamines conjugated to plasma membrane[J].Postharvest Biology and Technology, 2021, 179:111585.
[19] 胡苗. 采后褪黑素处理对‘华优’猕猴桃果实冷害和成熟衰老的影响[D].杨凌:西北农林科技大学, 2018.HU M.Effect of melatonin treatment on postharvest fruit chilling injury and senescence in ‘Hua You’ Kiwifruit[D].Yangling:Northwest A &F University, 2018.
[20] WANG Z Q, PU H L, SHAN S S, et al.Melatonin enhanced chilling tolerance and alleviated peel browning of banana fruit under low temperature storage[J].Postharvest Biology and Technology, 2021, 179:111571.
[21] LIU G S, ZHANG Y X, YUN Z, et al.Melatonin enhances cold tolerance by regulating energy and proline metabolism in Litchi fruit[J].Foods, 2020, 9(4):454.
[22] WANG T, HU M J, YUAN D B, et al.Melatonin alleviates pericarp browning in Litchi fruit by regulating membrane lipid and energy metabolisms[J].Postharvest Biology and Technology, 2020, 160:111066.
[23] KONG X M, GE W Y, WEI B D, et al.Melatonin ameliorates chilling injury in green bell peppers during storage by regulating membrane lipid metabolism and antioxidant capacity[J].Postharvest Biology and Technology, 2020, 170:111315.
[24] KEBBEH M, DONG J X, HUAN C, et al.Melatonin treatment alleviates chilling injury in mango fruit ‘Keitt’ by modulating proline metabolism under chilling stress[J].Journal of Integrative Agriculture, 2023, 22(3):935-944.
[25] BHARDWAJ R, AGHDAM M S, ARNAO M B, et al.Melatonin alleviates chilling injury symptom development in mango fruit by maintaining intracellular energy and cell wall and membrane stability[J].Frontiers in Nutrition, 2022, 9:936932.
[26] ALI S, NAWAZ A, NAZ S, et al.Exogenous melatonin mitigates chilling injury in zucchini fruit by enhancing antioxidant system activity, promoting endogenous proline and GABA accumulation, and preserving cell wall stability[J].Postharvest Biology and Technology, 2023, 204:112445.
[27] MADEBO M P, LUO S M, WANG L, et al.Melatonin treatment induces chilling tolerance by regulating the contents of polyamine, γ-aminobutyric acid, and proline in cucumber fruit[J].Journal of Integrative Agriculture, 2021, 20(11):3060-3074.
[28] LEI X Y, ZHU R Y, ZHANG G Y, et al.Attenuation of cold-induced apoptosis by exogenous melatonin in carrot suspension cells:The possible involvement of polyamines[J].Journal of Pineal Research, 2004, 36(2):126-131.
[29] 苗萌. 外源褪黑素处理对‘青香蕉’苹果虎皮病发生的影响[D].泰安:山东农业大学, 2021.MIAO M.Effects of exogenous melatonin on superficial scald of ‘White Winter Pearmain’ apple[D].Taian:Shandong Agricultural University, 2021.
[30] 王锋, 赵旗峰, 张晓萍, 等.壳聚糖-纳米ZnO-褪黑素复合涂膜对黄瓜冷害的影响及其机制研究[J].食品与发酵工业, 2022, 48(9):201-207.WANG F, ZHAO Q F, ZHANG X P, et al.Effect of chitosan-nano-ZnO-melatonin composite coating on cucumber chilling injury and mechanism[J].Food and Fermentation Industries, 2022, 48(9):201-207.
[31] 吕麟琳, 程顺昌, 高超, 等.1-MCP对冷胁迫‘香蕉李’磷脂组分和冷害影响研究[J].包装工程, 2019, 40(17):1-7.LYU L L, CHENG S C, GAO C, et al.Effects of 1-MCP on phospholipid components and chilling injury of ‘banana plums’ under cold stress[J].Packaging Engineering, 2019, 40(17):1-7.
[32] 孔祥佳, 林河通, 郑俊峰, 等.热空气处理诱导冷藏橄榄果实抗冷性及其与膜脂代谢的关系[J].中国农业科学, 2012, 45(4):752-760.KONG X J, LIN H T, ZHENG J F, et al.Hot-air treatment induced chilling tolerance of cold-stored Chinese olive fruits and its relation to the metabolism of membrane lipids[J].Scientia Agricultura Sinica, 2012, 45(4):752-760.
[33] 张婷, 车凤斌, 潘俨, 等.哈密瓜果实耐冷性与细胞膜脂肪酸的关系[J].园艺学报, 2015, 42(12):2421-2428.ZHANG T, CHE F B, PAN Y, et al.Relationship between chilling tolerance and membrane fatty acids of Hami melon[J].Acta Horticulturae Sinica, 2015, 42(12):2421-2428.
[34] LIANG S M, KUANG J F, JI S J, et al.The membrane lipid metabolism in horticultural products suffering chilling injury[J].Food Quality and Safety, 2020, 4(1):9-14.
[35] 宋聪慧, 郭水欢, 史小强, 等.褪黑素调控果蔬采后保鲜研究进展[J].食品科学, 2023, 44(3):228-236.SONG C H, GUO S H, SHI X Q, et al.Research progress on the regulatory effect of melatonin on postharvest preservation of fruits and vegetables[J].Food Science, 2023, 44(3):228-236.
[36] GAO Y, WANG Y, QIAN J, et al.Melatonin enhances the cadmium tolerance of mushrooms through antioxidant-related metabolites and enzymes[J].Food Chemistry, 2020, 330:127263.
[37] 朱玲玲, 胡花丽, 罗淑芬, 等.褪黑素调控呼吸代谢及抗氧化活性延缓采后青花菜衰老[J].农业工程学报, 2018, 34(3):300-308.ZHU L L, HU H L, LUO S F, et al.Melatonin delaying senescence of postharvest broccoli by regulating respiratory metabolism and antioxidant activity[J].Transactions of the Chinese Society of Agricultural Engineering, 2018, 34(3):300-308.
[38] 王蕾. 外源褪黑素调控采后葡萄酚类物质代谢机制研究[D].杭州:浙江大学, 2020.WANG L.Study on the regulation of phenolic compounds of grape in response to exogenous melatonin[D].Hangzhou:Zhejiang University, 2020.
[39] WANG P, YIN L H, LIANG D, et al.Delayed senescence of apple leaves by exogenous melatonin treatment:Toward regulating the ascorbate-glutathione cycle[J].Journal of Pineal Research, 2012, 53(1):11-20.
[40] SHANG F Z, LIU R L, WU W J, et al.Effects of melatonin on the components, quality and antioxidant activities of blueberry fruits[J].LWT, 2021, 147:111582.
[41] DONG B Y, YAO Q P, ZHU D Q, et al.Exogenous melatonin maintains quality of postharvest Rosa roxburghii fruit by modulating reactive oxygen species metabolism and energy status[J].Scientia Horticulturae, 2022, 304:111346.
[42] LI L, KITAZAWA H, ZHANG X H, et al.Melatonin retards senescence via regulation of the electron leakage of postharvest white mushroom (Agaricus bisporus)[J].Food Chemistry, 2021, 340:127833.
[43] PAN Y G, ZHANG S Y, YUAN M Q, et al.Effect of Glycine betaine on chilling injury in relation to energy metabolism in Papaya fruit during cold storage[J].Food Science &Nutrition, 2019, 7(3):1123-1130.
[44] 李美玲, 林育钊, 王慧, 等.能量状态在果蔬采后衰老中的作用及其调控研究进展[J].食品科学, 2019, 40(9):290-295.LI M L, LIN Y Z, WANG H, et al.Recent advances in the role and regulation of energy status in senescence of harvested fruits and vegetables[J].Food Science, 2019, 40(9):290-295.
[45] 张林, 陈翔, 吴宇, 等.脯氨酸在植物抗逆中的研究进展[J].江汉大学学报(自然科学版), 2023, 51(1):42-51.ZHANG L, CHEN X, WU Y, et al.Research progress of proline in plant stress resistance[J].Journal of Jianghan University (Natural Science Edition), 2023, 51(1):42-51.
[46] CAO S F, SONG C B, SHAO J R, et al.Exogenous melatonin treatment increases chilling tolerance and induces defense response in harvested peach fruit during cold storage[J].Journal of Agricultural and Food Chemistry, 2016, 64(25):5215-5222.
[47] SUN H J, LUO M L, ZHOU X, et al.Influence of melatonin treatment on peel browning of cold-stored “Nanguo” pears[J].Food and Bioprocess Technology, 2020, 13(8):1478-1490.
[48] HUANG Q, SONG H L, PAN Y G, et al.Exogenous arginine enhances the chilling tolerance in postharvest Papaya fruit by regulating arginine and proline metabolism[J].Journal of Food Processing and Preservation, 2021, 45(10):e15821.
[49] CAO S F, CAI Y T, YANG Z F, et al.MeJA induces chilling tolerance in loquat fruit by regulating proline and γ-aminobutyric acid contents[J].Food Chemistry, 2012, 133(4):1466-1470.
[50] 黄琦辉, 蔺凯丽, 黄琦, 等.丁香酚熏蒸对青茄采后冷害和脯氨酸代谢的影响[J].核农学报, 2018, 32(5):907-915.HUANG Q H, LIN K L, HUANG Q, et al.Effect of eugenol fumigation on chilling injury and proline metabolism in green eggplant[J].Journal of Nuclear Agricultural Sciences, 2018, 32(5):907-915.
[51] AGHDAM M S, LUO Z S, JANNATIZADEH A, et al.Employing exogenous melatonin applying confers chilling tolerance in tomato fruits by upregulating ZAT2/6/12 giving rise to promoting endogenous polyamines, proline, and nitric oxide accumulation by triggering arginine pathway activity[J].Food Chemistry, 2019, 275:549-556.
[52] 刘建龙. 外源褪黑素对梨果实发育、采后品质和抗轮纹病的影响及其调控机制研究[D].杨凌:西北农林科技大学, 2019.LIU J L.Effects of exogenous melatonin on pear fruit development, postharvest quality and resistance to ring rot and its regulation mechanism[D].Yangling:Northwest A &F University, 2019.
[53] 胡容平, 范中菡, 董义霞, 等.褪黑素对葡萄果实品质的影响[J].北方园艺, 2022(4):39-44.HU R P, FAN Z H, DONG Y X, et al.Effects of melatonin on fruit quality of grape[J].Northern Horticulture, 2022(4):39-44.
[54] FAN Y T, LI C Y, LI Y H, et al.Postharvest melatonin dipping maintains quality of apples by mediating sucrose metabolism[J].Plant Physiology and Biochemistry, 2022, 174:43-50.
[55] 陈克明, 陈伟, 杨震峰.桃果实采后可溶性糖和果胶类物质的变化与低温冷害的关系[J].核农学报, 2013, 27(5):647-652.CHEN K M, CHEN W, YANG Z F.The relationship between the changes in souble sugars and pectins contents and chilling injure of postharvest peach fruit[J].Journal of Nuclear Agricultural Sciences, 2013, 27(5):647-652.
[56] ZHAO Y Y, SONG C C, BRUMMELL D A, et al.Jasmonic acid treatment alleviates chilling injury in peach fruit by promoting sugar and ethylene metabolism[J].Food Chemistry, 2021, 338:128005.
[57] ZHAO H D, JIAO W X, CUI K B, et al.Near-freezing temperature storage enhances chilling tolerance in nectarine fruit through its regulation of soluble sugars and energy metabolism[J].Food Chemistry, 2019, 289:426-435.
[58] 吴雪霞, 张圣美, 张爱冬, 等.外源褪黑素对高温胁迫下茄子幼苗光合和生理特性的影响[J].植物生理学报, 2019, 55(1):49-60.WU X X, ZHANG S M, ZHANG A D, et al.Effect of exogenous melatonin on photosynthetic and physiological characteristics of eggplant seedlings under high temperature stress[J].Plant Physiology Journal, 2019, 55(1):49-60.
[59] 徐利伟, 岑啸, 李林香, 等.外源褪黑素对低温胁迫下桃果实蔗糖代谢的影响[J].核农学报, 2017, 31(10):1963-1971.XU L W, CEN X, LI L X, et al.Effect of exogenous melatonin on sucrose metabolism in peach fruit exposed to low temperature stress[J].Journal of Nuclear Agricultural Sciences, 2017, 31(10):1963-1971.
[60] ZHAO H Y, WANG L, BELWAL T, et al.Chitosan-based melatonin bilayer coating for maintaining quality of fresh-cut products[J].Carbohydrate Polymers, 2020, 235:115973.
[61] 张皓波, 吴喜庆, 杨蕊, 等.褪黑素结合气调包装处理对黄牛肝菌保鲜效果影响[J].食用菌学报, 2023, 30(3):68-80.ZHANG H B, WU X Q, YANG R, et al.Effects of melatonin combined with MAP treatment on preservation of Boletus flavus[J].Acta Edulis Fungi, 2023, 30(3):68-80.
[62] 朱芹. 外源褪黑素和热处理对冷藏水蜜桃冷害发生的影响[D].扬州:扬州大学, 2020.ZHU Q.Effect of exogenous melatonin and heat treatment on chilling injury of peach[D].Yangzhou:Yangzhou University, 2020.
[63] 骆思铭. 甜菜碱复合褪黑素处理对黄瓜保鲜效果的研究[D].南京:南京农业大学, 2019.LUO S M.Effect of Glycine betaine combined with melatonin treatment on the preservation of cucumber fruits[D].Nanjing:Nanjing Agricultural University, 2019.
[64] LIN X X, WANG L, HOU Y Y, et al.A combination of melatonin and ethanol treatment improves postharvest quality in bitter melon fruit[J].Foods, 2020, 9(10):1376.
[65] MEDINA-SANTAMARINA J, SERRANO M, RUIZ-ARACIL M C, et al.A synergistic effect based on the combination of melatonin with 1-methylcyclopropene as a new strategy to increase chilling tolerance and general quality in zucchini fruit[J].Foods, 2022, 11(18):2784.
[66] JIAO X, DENG B, ZHANG L X, et al.Melatonin and 1-methylcyclopropene improve the postharvest quality and antioxidant capacity of ‘youhou’ sweet persimmons during cold storage[J].International Journal of Fruit Science, 2022, 22(1):809-825.