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Polypropylene crisper and 1-MCP delay the softening,lignification and transcription levels of related enzyme genes of golden needle mushrooms(Flammulina velutipes)

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Journal of Integrative Agriculture 2022年第1期21卷 249-260页

作者： WANG Wen-jun LI Yao LI Fu-hua zeng kai-fang MING Jian College of Food Science Southwest UniversityChongqing 400715P.R.China Research Center of Food Storage&Logistics Southwest UniversityChongqing 400715P.R.China

The fresh postharvest golden needle mushroom(Flammulina velutipes) sporocarp has a high moisture content and crisp texture, but it still has high physiological activity and respiration, leading to senescence and quality *** with 1-methylcyclopropene(1-MCP) and polypropylene(PP) crispers were used to study the changes of lignification and softening of F. velutipes during storage. The main findings were as follows: the crisper packaging could effectively prolong the storage time of F. velutipes;either the 1-MCP treatment, crisper packaging or the combination of the two treatments could significantly inhibit the accumulation of lignin and the decreases in the contents of cellulose and pectin, and had certain inhibitory effects on the activities of enzymes involved in lignification and softening including phenylalanine ammonia-lyase(PAL), cinnamyl alcohol dehydrogenase(CAD), cellulase(Cx), pectin methylesterase(PME) and polygalacturonase(PG). Among them, the inhibitory effect of the crisper packaging was higher than the 1-MCP treatment, while the combination of the two treatments was the best. The results of transmission electron microscopy(TEM) and scanning electron microscopy(SEM) showed that the crisper packaging in combination with the 1-MCP treatment could effectively maintain the integrity and stability of the F. velutipes cellular structure and inhibit the emergence of plasmolysis to prevent cell membrane rupture. The transcription levels showed that the crisper packaging and the combination of the 1-MCP treatment and crisper packing could effectively affect the expression of genes for enzymes related to lignification and softening of F. velutipes. In conclusion, 1-MCP and PP crispers could delay the lignification and softening of F. velutipes during storage.

关键词： Flammulina velutipes polypropylene crisper 1-MCP softening and lignification transcription levels

Effects of methionine treatment on storage quality and antioxidant activity of postharvest jujube fruit

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Journal of Integrative Agriculture 2023年第9期22卷 2893-2904页

作者： LIU Yao LEI Xing-meng GUO Yu-xiao YAO Shi-xiang zeng kai-fang College of Food Science Southwest UniversityChongqing 400715P.R.China Food Storage and Logistics Research Center Southwest UniversityChongqing 400715P.R.China National Citrus Engineering Research Center Chongqing 400712P.R.China

Jujube fruits usually suffer from physiological disorders or infectious diseases during storage,leading to quality deterioration,softening,or ***,this study aims to investigate the effect of methionine soaking treatment on the postharvest jujube fruit decay rate and storage *** treatment significantly reduced the decay rate of postharvest jujube fruit and effectively maintained fruit color and titratable *** treatment effectively delayed the decrease of firmness,soluble solids,ascorbic acid,and lignin contents in jujube *** treatment reduced the content of alanine and phenylalanine,and increased the content of glycine in jujube fruit,but displayed no significant effect on total amino acid *** addition,jujube fruits in the methionine treatment group had a higher total phenolic and flavonoid content and antioxidant capacity,both in free and bound *** with the control,methionine treatment also significantly increased the content of individual phenolic acid fractions(gallic acid,vanillic acid,and syringic acid)and flavonoid fractions(catechin,epicatechin,rutin)in free form as well as individual phenolic acid fractions in bound form(gallic acid and ferulic acid)in jujube ***,this study suggested that the methionine treatment could be used as a prospective preservative to reduce the postharvest decay of jujube fruit and alleviate its nutritional quality deterioration during cold storage at 4°C.

关键词： methionine jujube decay rate sensory quality nutritional value

Changes in phenolic content,composition,and antioxidant activity of blood oranges during cold and on-tree storage

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Journal of Integrative Agriculture 2022年第12期21卷 3669-3683页

作者： ZHAO Ji-chun AO Miao HE Xiao-qin LI Wei-zhou DENG Li-li zeng kai-fang MING Jian College of Food Science Southwest UniversityChongqing 400715P.R.China Research Center of Food Storage&Logistics Southwest UniversityChongqing 400715P.R.China

Citrus fruits are rich in phenolic compounds that possess several health ***,few studies have focused on the changes in phenolic compounds in citrus fruits during postharvest *** study dynamically monitored the phenolic content,components and antioxidant activity of‘Tarocco’blood oranges during a period of 12-week cold storage and on-tree storage,*** investigated the alteration mechanism of phenolic compounds in blood oranges by evaluating phenylpropanoid pathway-related enzyme activities and gene *** showed that flavanones were the main phenolic compounds in blood *** storage methods mainly stimulated the accumulation of phenolic acids to improve total phenolic content,which reached the maximum at week ***,blood oranges had a higher phenolic content and antioxidant activity under on-tree storage than cold ***,the enzyme activities and gene expression of the phenylpropanoid pathway demonstrated that the accumulation of phenolics in blood oranges during storage was highly related to the activation of the phenylpropanoid *** results demonstrate that on-tree storage is a potential approach for extending the supply period of blood orange from the perspective of phenolic compounds.

关键词： ‘Tarocco’blood orange polyphenol components antioxidant ability phenylpropanoid pathway on-tree storage

温州蜜柑和椪柑橘络主要矿质元素含量的比较分析

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光谱学与光谱分析 2017年第4期37卷 1250-1253页

作者：姚世响谢姣曾凯芳西南大学食品科学学院重庆400715 重庆市特色食品工程技术研究中心重庆400715

橘络是位于柑橘果实中果皮与内果皮之间的维管束系统,主要起着营养物质和水分在果肉与果皮间转运的功能。橘络不仅在柑橘果实采前发育和采后枯水病发生过程中起重要作用,还是一种重要的中药资源,具有多种功效。本研究对温州蜜柑和椪柑... 详细信息

橘络是位于柑橘果实中果皮与内果皮之间的维管束系统,主要起着营养物质和水分在果肉与果皮间转运的功能。橘络不仅在柑橘果实采前发育和采后枯水病发生过程中起重要作用,还是一种重要的中药资源,具有多种功效。本研究对温州蜜柑和椪柑橘络的外观形态与含水量进行分析,并利用火焰原子吸收光谱法对橘络的主要矿质元素(钾、钙、镁、铜、锌)含量进行测定,经过初步讨论,结果表明:(1)椪柑中橘络的含水量(63.57%±1.53%)显著低于温州蜜柑70.25%±0.24%,果肉含水量也呈现类似趋势。(2)橘络富含钾、钙、镁元素,浓度分别为:3 525~6 495,6 866~9 430,3 94~632mg·kg^(-1)干重;铜、锌元素含量分别为1.5~2.3和8.5~14.7mg·kg^(-1)干重。(3)橘络钾、钙、镁、锌元素含量在椪柑中明显高于温州蜜柑。本研究首次揭示了橘络矿质元素的含量特征,并发现矿质元素的含量变化与果实含水量具有相关性,为进一步研究枯水病的发生机理提供了重要借鉴;同时也为开发橘络这一宝贵的中药资源奠定了理论基础。

关键词：橘络矿质元素火焰原子吸收光谱法温州蜜柑椪柑

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期68卷 219-237页

作者： Xia JIANG Yanyan fang Xianlin zeng Jian SUN Jie CHEN National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

关键词： proximal operator random reshuffling inexact computation compressed sensing nonsmooth optimization

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生长期套袋对果实品质和贮藏特性的影响

包装工程 2008年第6期29卷 21-22,37页

作者：曾凯芳西南大学重庆400715

综述了生长期套袋处理对果实贮藏品质如色泽、风味、香气、硬度,以及对采后生理如乙烯合成、呼吸作用等方面的影响,还介绍了套袋处理对果实采后病害的控制。结果表明:生长期套袋处理可以降低果实采收后果面的锈斑发生率、促进果皮色泽... 详细信息

综述了生长期套袋处理对果实贮藏品质如色泽、风味、香气、硬度,以及对采后生理如乙烯合成、呼吸作用等方面的影响,还介绍了套袋处理对果实采后病害的控制。结果表明:生长期套袋处理可以降低果实采收后果面的锈斑发生率、促进果皮色泽的转黄、有效控制潜伏侵染和采后病害的发生;但对果实的后熟衰老以及贮藏品质影响不大。

关键词：套袋果实品质贮藏特性

采后壳聚糖处理对果实-病原菌互作中形态结构的影响

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食品科学 2013年第11期34卷 305-310页

作者：张璐曾凯芳西南大学食品科学学院重庆400716 西南大学国家食品科学与工程实验教学中心重庆400716

壳聚糖是天然多糖中唯一的碱性多糖,具有许多特殊的理化性质和生理功能,在果蔬采后保鲜中有广阔的应用前景。壳聚糖在控制采后果蔬病害中发挥作用,是壳聚糖-果实-病原菌三方交互作用的结果,壳聚糖在形态结构、生理、生化各个水平上,对果... 详细信息

壳聚糖是天然多糖中唯一的碱性多糖,具有许多特殊的理化性质和生理功能,在果蔬采后保鲜中有广阔的应用前景。壳聚糖在控制采后果蔬病害中发挥作用,是壳聚糖-果实-病原菌三方交互作用的结果,壳聚糖在形态结构、生理、生化各个水平上,对果实-病原菌互作产生影响。形态结构的变化最能直观地反映三者的相互作用,形态结构水平的研究为生理生化水平的研究奠定基础,因此本文从形态结构的角度,综述采后壳聚糖处理对病原菌侵入果实组织后形态变化的影响,以及对受侵染果实的果皮细胞结构、物质成分变化的影响,探讨壳聚糖和采后果实、病原菌的互作关系,为进一步揭示壳聚糖的作用机理,及壳聚糖在采后果蔬病害控制上的进一步研究和应用提供理论依据。

关键词：壳聚糖病原菌果实互作形态结构

猕猴桃果实抗氧化活性物质及其在贮藏中的变化

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食品工业科技 2010年第8期31卷 393-395页

作者：杨丹曾凯芳西南大学食品科学学院重庆400715 重庆市特色食品工程技术研究中心重庆400716

猕猴桃果实营养丰富,含有多种抗氧化活性物质,包括酚类物质、维生素C、类胡萝卜素和维生素E,其中对抗氧化活性影响最大的是酚类物质和维生素C。本文概述了猕猴桃果实主要的抗氧化活性物质在贮藏过程中的变化,在不同的贮藏条件下,猕猴桃... 详细信息

猕猴桃果实营养丰富,含有多种抗氧化活性物质,包括酚类物质、维生素C、类胡萝卜素和维生素E,其中对抗氧化活性影响最大的是酚类物质和维生素C。本文概述了猕猴桃果实主要的抗氧化活性物质在贮藏过程中的变化,在不同的贮藏条件下,猕猴桃中抗氧化活性物质变化不同,但延缓后熟的贮藏条件基本都能延缓活性物质的降解。

关键词：猕猴桃果实抗氧化活性物质贮藏条件变化

膜醭毕赤酵母与壳聚糖复合处理对柑橘果实防御酶及防御物质的影响

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食品科学 2014年第10期35卷 212-217页

作者：彭茹张璐曾凯芳西南大学食品科学学院重庆400715 农业部农产品贮藏保鲜质量安全风险评估实验室(重庆) 重庆400715

研究膜醭毕赤酵母与壳聚糖复合处理对柑橘果实防御酶和防御物质的影响。采用损伤接种与无损伤浸泡复合液两种处理方式,分别研究经复合处理后果实防御酶和防御物质在7 d和28 d贮藏期内的变化。结果显示:与对照果实相比,复合液接种处理果... 详细信息

研究膜醭毕赤酵母与壳聚糖复合处理对柑橘果实防御酶和防御物质的影响。采用损伤接种与无损伤浸泡复合液两种处理方式,分别研究经复合处理后果实防御酶和防御物质在7 d和28 d贮藏期内的变化。结果显示:与对照果实相比,复合液接种处理果实中的苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)、多酚氧化酶(PPO)、几丁质酶、β-1,3葡聚糖酶(GLU)等防御酶在贮藏期内活性增加明显,其中以PAL、POD、GLU 3种防御酶最为明显,在贮藏第3天时均达到最大值;复合液浸泡处理果实中的PAL、POD、几丁质酶活性和木质素含量的增加较为明显,在贮藏第14天时达到最大值。结果表明,膜醭毕赤酵母与壳聚糖复合处理能够诱导柑橘果实中防御酶活性和防御物质含量的升高,从而起到提高果实抗病性的效果。防御酶在果实贮藏前期发挥较关键的抗病作用,而酚类、木质素等防御类物质则在贮藏后期发挥抗病作用。

关键词：诱导抗病性防御酶防御物质柑橘果实