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基于SBSE-GC-O-MS技术‘梅占’茶关键香气成分分析

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食品工业科技 2025年第2期46卷 271-279页

作者：欧晓西黄慧清李秋明余欣茹姜能宝林宏政郑玉成孙云福建农林大学园艺学院/茶学福建省高校重点实验室福建福州350002 尤溪县茶叶技术推广站福建三明353000 武夷学院茶与食品学院/茶叶福建省高校工程研究中心/武夷学院茶叶科学研究所福建武夷山354300

‘梅占’品种因其独特的品种特征香气深受人们的喜爱。为探究‘梅占’茶品种关键香气特征,本研究通过气相色谱-嗅闻-质谱联用(Gas Chromatography-Olfactory-Mass Spectrometry,GC-O-MS)技术对‘梅占’红茶、‘梅占’绿茶、‘梅占’乌... 详细信息

‘梅占’品种因其独特的品种特征香气深受人们的喜爱。为探究‘梅占’茶品种关键香气特征,本研究通过气相色谱-嗅闻-质谱联用(Gas Chromatography-Olfactory-Mass Spectrometry,GC-O-MS)技术对‘梅占’红茶、‘梅占’绿茶、‘梅占’乌龙茶三个茶类关键香气活性化合物进行鉴定和描述,同时结合香气活性值(Odor Activity Value,OAV)、香气特征影响值(Aroma Character Impact Value,ACI)和感官审评进行对比分析。感官审评结果表明‘梅占’红茶、‘梅占’绿茶、‘梅占’乌龙茶均具有明显的品种特征香气,其中‘梅占’红茶花香浓郁带甜香,‘梅占’绿茶花香清雅,嫩香持久,‘梅占’乌龙花香馥郁具奶香。偏最小二乘法(OPLS-DA)与OAV分析发现,芳樟醇、香叶醇、水杨酸甲酯、苯乙醇、茉莉内酯和吲哚是‘梅占’不同茶类香气差异的关键化合物。结合GC-O和OAV分析结果表明,芳樟醇、香叶醇、β-紫罗兰酮、茉莉酮等赋予了‘梅占’茶馥郁的花香、奶香等风味。通过本研究揭示了‘梅占’茶香气的化学基础,为研究‘梅占’茶特征香气形成机理提供了理论基础。

关键词： ‘梅占’茶搅拌棒吸附萃取气相色谱-嗅闻-质谱香气活性化合物香气活性值

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不同香型安溪黄金桂风味品质解析

食品科学 2025年第5期46卷 263-271页

作者：任卫威张宇航郑玉成陈文贤林宏政徐梦婷陈谢勇陈百文叶乃兴福建农林大学园艺学院农作物遗传育种与综合利用教育部重点实验室福建福州350002 武夷学院茶与食品学院福建武夷山354300 福建闻弦茶业有限公司福建安溪362400 福建省茶叶质量检测与技术推广中心福建福州350003

本研究采用感官评价、高效液相色谱、高效液相色谱-串联质谱及顶空固相微萃取-气相色谱-质谱对不同香型安溪黄金桂中的主要风味品质成分进行分析。结果表明,安溪黄金桂具有“芬芳四溢、味醇甘美”的特征,不同香型安溪黄金桂的感官品质... 详细信息

本研究采用感官评价、高效液相色谱、高效液相色谱-串联质谱及顶空固相微萃取-气相色谱-质谱对不同香型安溪黄金桂中的主要风味品质成分进行分析。结果表明,安溪黄金桂具有“芬芳四溢、味醇甘美”的特征,不同香型安溪黄金桂的感官品质各具特色,清香型黄金桂花果香清鲜持久、滋味鲜醇甘爽;浓香型黄金桂焙香浓郁有甜感、滋味浓醇甘爽。两种香型黄金桂共筛选出61种差异香气物质。基于气味活性值分析及香气特征影响(aroma character impact,ACI)值进一步分析,发现清香型黄金桂的甲基庚烯酮、水杨酸甲酯、正己醛和异戊醇的ACI值显著高于浓香型,推测上述物质为呈现清香、花香和果香的关键特征香气物质;浓香型黄金桂中的脱氢芳樟醇、桃金娘烯醇、2,5-二甲基-3-乙基吡嗪、2-乙酰基-3-甲基吡嗪、柠檬烯和藏红花醛ACI值显著高于清香型,推测上述物质为呈现烘焙香、花香和果香的关键特征香气物质。本研究初步探明了不同香型安溪黄金桂品质化学特征及其香气形成的物质基础,可为阐明安溪黄金桂风味品质特征提供科学依据。

关键词：安溪黄金桂香型滋味香气

Identification of PAL genes related to anthocyanin synthesis in tea plants and its correlation with anthocyanin content

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Horticultural Plant Journal 2022年第3期8卷 381-394页

作者： Xuejin Chen Pengjie Wang Mengya Gu Binghao Hou Churan Zhang yucheng zheng Yun Sun Shan Jin Naixing Ye College of Horticulture Fujian Agriculture and Forestry University/Key Laboratory of Tea Science in University of Fujian ProvinceFuzhou 350002China College of Horticulture Nanjing Agricultural UniversityNanjing 210095China

The phenylalanine ammonia-lyase(PAL)gene family in tea plants(Camellia sinensis L.)encodes the enzyme that catalyzes the first reaction of the phenylpropane metabolic *** present study aimed to characterize the PAL genes in tea plants,and get better insights on the CsPALs in anthocyanins *** CsPAL genes were identified and characterized in tea plants by bioinformatics *** analysis of CsPALs was conducted for its phylogenetic relationship,gene structure,chromosomal location,and protein conserved motifs based on tea plant *** cis-elements of CsPALs were responsive to light,abiotic stress,hormone,and MYB-binding ***,tissuespecific expression analysis showed that CsPAL4 was expressed preferentially in young leaves and *** analysis was performed in purple-leaf tea with anthocyanin components,and it was suggested that CsPAL4 was closely related with different anthocyanin accumulated,especially with cyanidin 3-O-galactoside,cyanidin 3-O-glucoside,and delphinidin ***,the putative upstream regulation factors CsMYBs(CsMYB59,CsARR1,CsSRM1,CsMYB101,and CsMYB52)and CsbHLHs(CsbHLH104,CsbHLH3,CsbIM1,CsTCP14,and CsPIF4)could bind to the promoter of CsPALs,thereby activating its *** study provides a theoretical basis for further research to elucidate the functions of the CsPAL genes.

关键词： Camellia sinensis Phenylalanine ammonia-lyase(PAL) Anthocyanin biosynthesis Expression pattern

Chromatin accessibility and translational Iandscapes of tea plants under chilling stress

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Horticulture Research 2021年第1期8卷 1458-1472页

作者： Pengjie Wang Shan Jin Xuejin Chen Liangyu Wu yucheng zheng Chuan Yue Yongchun Guo Xingtan Zhang Jiangfan Yang Naixing Ye College of Horticulture Fujian Agriculture and Forestry University/Key Laboratory of Tea Science in Universities of Fujian ProvinceFuzhou 350002China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China

Plants have evolved regulatory mechanisms at multiple levels to regulate gene expression in order to improve their cold ***,limited information is available regarding the stress response at the chromatin and translational ***,we characterize the chromatin accessibility,transcriptional,and translational landscapes of tea plants in vivo under chilling stress for the first *** stress signi ficantly affected both the transcription and translation levels as well as the translation efficiency of tea plants.A total of 3010 genes that underwent rapid and independent translation under chilling stress were observed,and they were signi ficantly enriched in the photosynthesis-antenna protein and phenylpropanoid biosynthesis pathways.A set of genes that were signi ficantly responsive to cold at the transcription and translation levels,including four(+)-neomenthol dehydrogenases(MNDs)and two(E)-nerolidol synthases(NESs)arranged in tandem on the chromosomes,were also *** detected potential upstream open reading frames(uORFs)on 3082 genes and found that tea plants may inhibit the overall expression of genes by enhancing the translation of uORFs under chilling *** addition,we identi fied distal transposase hypersensitive sites(THSs)and proximal THSs and constructed a transcriptional regulatory network for tea plants under chilling *** also identi fied 13 high-con fidence transcription factors(TFs)that may play a crucial role in cold *** results provide valuable information regarding the potential transcriptional regulatory network in plants and help to clarify how plants exhibit flexible responses to chilling stress.

关键词： stress chilling landscape

Effects of Cooling Rate on High-temperature Mechanical Properties of A356 Alloys

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稀有金属材料与工程 2011年第S3期40卷 63-68页

作者： Zhang Kai, Sun yucheng, Wang Suolin, zheng Hongliang, Xu Rongfu, Tian Xuelei Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061, China Shandong Univ Key Lab Liquid Solid Struct Evolut & Proc Mat Minist Educ Jinan 250061 Peoples R China

High temperature mechanical properties of A356 alloy castings under different solidification cooling rates have been studied and the influence of cooling rates on secondary dendrite arm spacing (SDAS) and mechanical properties has been discussed. To get different cooling rates, three different types of mold—green sand, green sand with chill and permanent mold, were used to pour castings which would subsequently be machined into tensile test and metallographic specimens. The temperature curves of castings’ solidification in three different mold were recorded using thermal couples, which would be used to calculate their corresponding cooling rates. Tensile tests were carried out at 20, 200, 300, 400 and 500 ℃ and then mechanical properties, such as tensile strength, yield strength, elongation, of specimens from different mold types at different test temperatures were obtained. And SDAS of different specimens were measured using optical metallographic photos. From integrated analysis of all those results, following conclusions could be reached. The relationship between SDAS and cooling rates is negative, and the quantitative relationship has been obtained through data fitting analyzing. Generally speaking, tensile strength and yield strength decease as the temperature elevates while elongation behaves in the contrary trend. Through the regression analysis of SDAS, mechanical properties and temperature, the relationship among them is obtained, which makes quantitative prediction of A356 alloy’s mechanical properties at different temperatures with different solidification cooling rates be possible.

关键词： A356 alloy high temperature mechanical properties cooling rate SDAS

Genetic basis of high aroma and stress toleranee in the oolong tea cultivar genome

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Horticulture Research 2021年第1期8卷 1256-1270页

作者： Pengjie Wang Jiaxin Yu Shan Jin Shuai Chen Chuan Yue Wenling Wang Shuilian Gao Hongli Cao yucheng zheng Mengya Gu Xuejin Chen Yun Sun Yuqiong Guo Jiangfan Yang Xingtan Zhang Naixing Ye College of Horticulture Fujian Agriculture and Forestry University/Key Laboratory of Tea Science in Universities of Fujian Province350002 FuzhouChina Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural Sciences518120 ShenzhenChina Center for Genomics and Biotechnology Fujian Provincial Key Laboratory of Haixia Applied Plant Systems BiologyKey Laboratory of GeneticsFujian Agriculture and Forestry University350002 FuzhouChina

Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the *** several chromosome-level tea plant genomes have been published,they collapsed the two haplotypes and ignored a large number of allelic variations that may underlie important biological functions in this ***,we present a phased chromosome-scale assembly for an elite oolong tea cultivar,"Huangdan",that is well known for its high levels of *** on the two sets of haplotype genome data,we identi fi ed numerous genetic variations and a substantial proportion of allelic imbalance related to important traits,including aroma-and stress-related *** genomics revealed extensive structural variations as well as expansion of some gene families,such as terpene synthases(TPSs),that likely contribute to the high-aroma characteristics of the backbone parent,underlying the molecular basis for the biosynthesis of aroma-related chemicals in oolong *** results uncovered the genetic basis of special features of this oolong tea cultivar,providing fundamental genomic resources to study evolution and domestication for the economically important tea crop.

关键词： sinensis cultivar elite

Rapid inactivation of human respiratory RNA viruses by deep ultraviolet irradiation from light-emitting diodes on a high-temperatureannealed AlN/Sapphire template

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Opto-Electronic Advances 2023年第9期6卷 31-43页

作者： Ke Jiang Simeng Liang Xiaojuan Sun Jianwei Ben Liang Qu Shanli Zhang Yang Chen yucheng zheng Ke Lan Dabing Li Ke Xu State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Virology College of Life SciencesWuhan UniversityWuhan 430072China Institute for Vaccine Research Animal Biosafety Level 3 LaboratoryWuhan UniversityWuhan 430072China

Efficient and eco-friendly disinfection of air-borne human respiratory RNA viruses is pursued in both public environment and portable *** AlGaN-based deep ultraviolet(DUV)light-emission diode(LED)has high practical potentials because of its advantages of variable wavelength,rapid sterilization,environmental protection,and ***,whether the emission wavelength has effects on the disinfection as well as whether the device is feasible to sterilize various respiratory RNA viruses under portable conditions is ***,we fabricate AlGaN-based DUV LEDs with different wavelength on high-temperature-annealed(HTA)AlN/Sapphire templates and investigate the inactivation effects for several respiratory RNA *** AlN/AlGaN superlattices are employed between the template and upper n-AlGaN to release the strong compressive stress(SCS),improving the crystal quality and interface *** LEDs with the wavelength of 256,265,and 278 nm,corresponding to the light output power of 6.8,9.6,and 12.5 mW,are realized,among which the 256 nm-LED shows the most potent inactivation effect in human respiratory RNA viruses,including SARS-CoV-2,influenza A virus(IAV),and human parainfluenza virus(HPIV),at a similar light power density(LPD)of~0.8 mW/cm2 for 10 *** results will contribute to the advanced DUV LED application of disinfecting viruses with high potency and broad spectrum in a portable and eco-friendly use.

关键词： AlGaN DUV LED superlattice SARS-CoV-2 influenza A virus

Lyocell纤维生产过程泄爆原因分析与对策

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上海纺织科技 2023年第6期51卷 42-45页

作者：郑玉成中纺院绿色纤维股份公司河南新乡453000

Lyocell纤维生产过程的安全控制是生产难点,易引起泄爆。对Lyocell纤维生产过程中纤维素/NMMO/水三元体系稳定性机理进行了分析,结合生产实践经验对稳定剂的使用和生产过程中的安全控制进行了分析。结果表明:生产过程要重视温度和铁、... 详细信息

Lyocell纤维生产过程的安全控制是生产难点,易引起泄爆。对Lyocell纤维生产过程中纤维素/NMMO/水三元体系稳定性机理进行了分析,结合生产实践经验对稳定剂的使用和生产过程中的安全控制进行了分析。结果表明:生产过程要重视温度和铁、铜离子的控制,PG和HA需要混合使用,要采取措施降低NMMO的分解,纺丝液制备和输送过程应该严格控制。

关键词： Lyocell纤维泄爆稳定剂铁铜离子温度分解

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海枣曲霉糖苷酶类的化学组成

微生物学报 1989年第6期29卷 432-438页

作者：曾宇成张树政中国科学院微生物研究所

本文测定的海枣曲霉糖苷酶均为糖蛋白,含糖量分别为:地衣多糖酶7.7%,木聚糖酶X-Ⅱ 5.8%,木聚糖酶X-Ⅲ 3.3%,β-半乳糖苷酶14.3%,β-葡萄糖苷酶16.1%,β-木糖苷酶15.5%。这几个酶的氨基酸组成有较大差异,但也有共同特点,即都含有较多酸... 详细信息

本文测定的海枣曲霉糖苷酶均为糖蛋白,含糖量分别为:地衣多糖酶7.7%,木聚糖酶X-Ⅱ 5.8%,木聚糖酶X-Ⅲ 3.3%,β-半乳糖苷酶14.3%,β-葡萄糖苷酶16.1%,β-木糖苷酶15.5%。这几个酶的氨基酸组成有较大差异,但也有共同特点,即都含有较多酸性与羟基氨基酸,含His,Met较少。将这些酶的氨基酸组成作成星状图,结果这些酶的星状图互不相同,只有β-葡萄糖苷酶和β-木糖苷酶的星状图之间有一定的相似性。比较海枣曲霉糖苷酶和其他来源的糖苷酶的氨基酸组成的星状图。发现不同来源的同一种酶都有不同程度的相似性,且相似程度与产生菌之间的亲缘关系有很大的相关性。

关键词：海枣曲霉糖苷酶化学组成