代谢组学解析遮阴对茶叶主要品质成分的影响

doi:10.3864/j.issn.0578-1752.2019.06.010

摘要/Abstract

摘要：

【目的】茶叶生产上常采用遮阴处理来提高其品质,然而,黑暗遮阴对茶叶品质的影响尚未清楚。本文重点研究黑暗遮阴对茶叶中主要品质成分的影响,以期更加详细了解遮阴与茶叶品质的关系。【方法】利用遮阳网对茶树进行中度（65.0%）、黑暗（99.7%）两个遮阴处理,不遮阴作为对照;采用紫外分光光度法检测总多酚、总氨基酸、总黄酮的含量,同时采用超高效液相色谱-四级杆-飞行时间质谱（UHPLC-Q-TOF/MS）对茶叶中的主要品质成分进行详细调查。【结果】与对照相比,中度遮阴显著降低了茶叶的总氨基酸、总黄酮含量（P<0.05）,轻微降低了总多酚含量,增加了酚氨比;黑暗遮阴显著降低了总氨基酸和总黄酮含量,显著增加了总多酚含量和酚氨比（P<0.05）。主成分分析（PCA）表明,两个遮阴处理明显改变了茶树叶片的代谢组。进一步鉴定得到了87个化合物,包括2个生物碱、18个氨基酸、12个儿茶素类、8个儿茶素二聚体类、19个黄酮（醇）糖苷、5个香气糖苷、6个核苷（酸）、9个酚酸、8个其他化合物;与对照相比,82个化合物在遮阴处理后出现显著差异（P<0.05）。遮阴后,生物碱含量显著增加;氨基酸呈现多样性变化,半数以上氨基酸含量显著下降;部分儿茶素类及二聚儿茶素类物质的含量在中度遮阴后显著降低,然而大部分儿茶素类和儿茶二聚体素类物质的含量却在黑暗遮阴后显著上升;绝大部分黄酮（醇）糖苷的含量在遮阴后出现显著下降,且遮阴程度越高,下降越多;大部分香气糖苷含量在遮阴后显著上升;大部分核苷（酸）含量在遮阴后显著降低;多数酚酸的含量在遮阴后显著上升。【结论】黑暗遮阴后,生物碱、儿茶素类及儿茶素二聚体类等物质含量显著上升,氨基酸含量显著下降,酚氨比显著上升,预示黑暗遮阴处理可能不利于提高茶叶的品质。

关键词: 茶叶, 遮阴, 代谢组学, 液质联用, 次生代谢

Abstract:

【Objective】Shading treatment is widely used to improve the quality of teas in tea yielding. However, the effects of dark shading on the quality of teas remain unclear. This study focused on the effects of dark shading on the main quality components in teas to understand the relationship between shading and tea quality in detail.【Method】Moderate (65.0%) and dark (99.7%) shading treatments were applied to tea plants by using black shading net, with non-shading as control. Ultraviolet spectrophotometry was employed to determine the contents of total polyphenols, total amino acids and total flavonoids, and ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was employed to investigate the quality components in tea leaves.【Result】Compared with the control group, moderate shading treatment significantly reduced the contents of total amino acids and total flavonoids (P<0.05), and slightly reduced the content of total polyphenols, and therefore increased the ratio of polyphenols to amino acids. Dark shading treatment significantly reduced the contents of total amino acids and total flavonoids, while significantly increased the contents of total polyphenols and the ratio of phenol to ammonia (P<0.05). Principal component analysis showed that the two shading treatments significantly changed the metabolite pattern in tea leaves. A total of 87 compounds were identified, including 2 alkaloids, 18 amino acids, 12 catechins, 8 dimeric catechins, 19 flavone glycosides and flavonol glycosides, 5 glycosidically bound volatiles (GBVs), 6 nucleosides and nucleotides, 9 phenolic acids, and 8 other compounds. The contents of 82 compounds in two shading groups showed significant differences comparing with the control (P<0.05). After shading, the contents of alkaloids significantly increased; amino acids showed various change trends, with the contents of more than half of amino acids significantly decreased. The contents of several catechins and dimeric catechins significantly decreased in moderate shading group, while the contents of most catechins and their dimers significantly increased in dark shading group. The content of most flavone glycosides and flavonol glycosides showed decreased trend along with the increase of shading degree. The contents of most GBVs significantly increased. The contents of most of nucleosides and nucleotides significantly decreased; the content of most phenolic acids significantly increased.【Conclusion】After dark shading treatment, the contents of alkaloids, catechins and dimeric catechins significantly increased, while the contents of amino acids significantly decreased, and therefore the ratio of phenol to ammonia significantly increased, which indicated that dark shading might not contribute to improve the tea quality.

Key words: tea, shading, metabolomics, LC-MS, secondary metabolism

陈勤操,戴伟东,蔺志远,解东超,吕美玲,林智. 代谢组学解析遮阴对茶叶主要品质成分的影响[J]. 中国农业科学, 2019, 52(6): 1066-1077.

CHEN QinCao,DAI WeiDong,LIN ZhiYuan,XIE DongChao,LÜ MeiLing,LIN Zhi. Effects of Shading on Main Quality Components in Tea (Camellia Sinensis (L) O. Kuntze) Leaves Based on Metabolomics Analysis[J]. Scientia Agricultura Sinica, 2019, 52(6): 1066-1077.

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链接本文: https://www.chinaagrisci.com/CN/10.3864/j.issn.0578-1752.2019.06.010

https://www.chinaagrisci.com/CN/Y2019/V52/I6/1066

图/表 4

图1

表1

图2

表2

茶叶中鉴定到的化合物及其相对含量（峰面积,counts）"

编号 NO.	化合物 Compound	对照 CK	中度遮阴（M） Moderate shading	黑暗遮阴（D） Dark shading
	生物碱 Alkaloids
1	可可碱 Theobromine*	21601922±564017a	23610245±1235150b	31765707±910344c
2	咖啡碱 Caffeine*	81927164±669239a	84157969±833682b	92249135±626755c
	氨基酸 Amino acids
3	赖氨酸 Lysine*	415102±33333a	304636±13196b	287939±21857b
4	组氨酸 Histidine*	106521±2331a	114046±1501b	115505±4088b
5	精氨酸 Arginine*	1080777±17439a	411284±30083b	310232±11544c
6	谷氨酰胺 Glutamine*	11504894±248750a	9510890±228064b	8544787±165748c
7	天冬酰胺 Asparagine*	269010±4047a	330815±12527b	386838±12683c
8	天冬氨酸 Aspartic acid*	2471046±65470a	3061948±147858b	3511442±163262c
9	苏氨酸 Threonine*	508856±15011a	541787±29692a	658518±34367b
10	谷氨酸 Glutamic acid*	12341565±309155a	13270317±611986b	13439150±632674b
11	脯氨酸 Proline*	2645963±379642a	2440953±213986ab	2108482±62378b
12	哌啶酸 Pipecolic acid	3248531±142042a	2935336±171353b	1764292±38796c
13	缬氨酸 Valine*	2339386±101496a	2238141±130139a	1919611±60701b
14	焦谷氨酸 Pyroglutamic acid	1062221±57097a	811492±72660b	771975±48705b
15	茶氨酸 Theanine*	68360338±585955a	66479617±411838b	68385572±731671a
16	络氨酸 Tyrosine*	1786868±93078a	1549169±153847b	1106611±81550c
17	亮氨酸 Leucine*	1443868±81819a	1408718±79026a	1573454±70977b
18	异亮氨酸 Isoleucine*	3262703±121220a	3024099±132531ab	2798292±251013b
19	苯丙氨酸 Phenylalanine*	4853644±269826a	4666955±267358a	2267113±388453b
20	色氨酸 Tryptophan*	5472135±160789a	5984855±345522b	11062018±429397c
	儿茶素类物质 Catechins
21	没食子儿茶素 GC*	10739724±248150a	7266229±1746807b	6619543±177288b
22	表没食子儿茶素 EGC*	39500597±1284644a	37443505±1664176b	34546359±1417812c
23	儿茶素 C*	8415688±210799a	7060237±384357b	8382320±246267a
24	表没食子儿茶素没食子酸酯 EGCG*	29958037±706088a	30326483±808249a	34639578±1220789b
25	表没食子儿茶素-3,5-二没食子酸酯 EGC 3,5-digallate	273480±42970a	283272±48547a	1053013±139393b
26	没食子儿茶素没食子酸酯 GCG	972901±112326a	1030902±94020a	1425857±71356b
27	表儿茶素 EC*	19771924±1020879a	18019916±667293b	19623903±522374a
28	表没食子儿茶素-3- (3-O-甲基)没食子酸酯 EGCG3''Me*	120447±4955a	140818±4851b	199237±10846c
29	表儿茶素没食子酸酯 ECG*	18779724±793807a	17384430±501165a	24909140±1543699b
30	表阿夫儿茶精 Epiafzelechin*	734021±40623a	779426±44759a	632343±30136b
31	表没食子儿茶素-3-O (4-O-甲基)没食子酸酯 EGCG4''Me	172678±3694a	186962±6304b	117215±7432c
32	表阿夫儿茶精-3-没食子酸酯 Epiafzelechin 3-gallate	361261±14773a	417017±48019a	872386±74888b
	儿茶素二聚体类物质 Dimeric catechins
33	原花青素B3 Procyanidin B3	1456926±144947a	1318465±164090a	1777328±154439b
34	原花青素B5 Procyanidin B5	676231±36224a	607400±27511a	865820±81000b
35	原花青素B1 Procyanidin B1	12734590±529138a	11845963±653962a	14682473±1649024b
36	原花青素B2 Procyanidin B2*	3648511±97335a	3372480±218490b	4396056±133796c
37	原花青素C1 Procyanidin C1	442411±27557a	407848±31717a	576841±29677b
38	聚酯型儿茶素B Theasinensin B	2686283±501963a	2475063±384834a	2088193±324752a
39	聚酯型儿茶素A Theasinensin A	1078878±239782a	1060887±272465a	1853021±224828b
40	表儿茶素-4α-8-表儿茶素没食子酸酯 EC-(4alpha->8)-ECG	3126006±328977a	3187820±548213a	3992103±491254b
	黄酮（醇）糖苷 Flavone glycosides and flavonol glycosides
41	芹菜素 6,8-C-二葡萄糖苷 Apigenin 6,8-C-diglucoside*	1613798±56930a	1630940±131948a	777980±59120b
42	芹菜素 6-C-葡糖-8-C-阿拉伯糖苷 Apigenin 6-C-glucosyl-8-C-arabinoside	1660183±106041a	1503259±97807b	810637±78142c
43	芹菜素 6-C-阿拉伯糖-8-C-葡萄糖苷 Apigenin 6-C-arabinoside-8-C-glucoside	1496711±129603a	1518132±151862a	788376±65889b
44	槲皮素三葡萄糖苷1 Quercetin triglucoside1	1612840±57495a	1363996±78280b	580505±25067c
45	槲皮素二葡萄糖苷 Quercetin diglucoside	67381±3565a	55609±3754b	107029±9284c
46	槲皮素三葡萄糖苷2 Quercetin triglucoside2	1084804±46160a	1141132±51278a	638989±30546b
47	杨梅酮 3-葡萄糖苷 Myricetin 3-glucoside	18182085±616935a	12072654±310669b	3589507±251769c
48	牡荆素 Vitexin (Apigenin 8-C-glucoside)*	765594±51330a	782206±55471a	271503±22369b
49	异牡荆素 Isovitexin (Apigenin 6-C-glucoside)*	1181313±24234a	979750±147049b	233632±18079c
50	槲皮素 3-半乳糖苷Quercetin 3-O-galactoside*	1099792±11518a	506247±12394b	143146±3610c
51	槲皮素 3-葡萄糖酰芸香糖苷 Quercetin 3-O-glucosylrutinoside	14979656±3750206a	8112166±2330341b	3161317±67104c
52	芦丁 Rutin (Quercetin 3-rutinoside)*	2164395±550873a	1090625±197167b	198801±14635c
53	异槲皮苷 Isoquercitrin (Quercetin 3-glucoside)*	17026726±301235a	7759338±124311b	1851133±23502c
54	山奈酚 3-半乳糖酰芸香糖苷 Kaempferol 3-galactosylrutinoside	7541465±350174a	7835962±171382a	4825756±137690b
55	山奈酚 3-葡糖酰芸香糖苷 Kaempferol 3-glucosylrutinoside	7016794±174776a	5664808±182475b	1898898±51123c
56	山奈酚 3-半乳糖苷 Kaempferol 3-O-galactoside*	23176288±330927a	20712077±535708b	7805419±171856c
57	山奈酚 3-芸香糖苷 Kaempferol 3-O-rutinoside*	2816105±37743a	1598996±83538b	483109±13085c
58	山奈酚 3-葡萄糖苷 Kaempferol 3-O-glucoside*	5081721±116589a	3529878±58811b	936048±18986c
59	山奈酚 3-阿拉伯糖苷 Kaempferol 3-O-arabinoside*	1525796±41047a	1362198±34642b	469329±16088c
	香气糖苷 Glycosidically bound volatiles
60	苯甲基樱草糖苷 Benzyl primeveroside	355943±33789a	418331±21363b	457889±16047c
61	苯乙基樱草糖苷 Phenylethyl primeveroside	303228±36908a	670857±67252b	2026015±184020c
62	顺-3-己烯基樱草糖苷 cis-3-Hexenyl b-primeveroside	115287±8765a	129325±6209b	219121±11667c
63	芳樟醇氧化物樱草糖苷 Linalool oxide primeveroside	2152086±267169a	2604541±163205b	972995±35694c
64	芳樟基樱草糖苷 Linalyl primeveroside	142195±5721a	232484±9465b	256285±15269c
	核苷（酸） Nucleosides and nucleotides
65	腺嘌呤核苷二磷酸 ADP	289424±11725a	241159±17959b	233107±15448b
66	腺嘌呤核苷酸 AMP	2320655±155694a	2183139±147428a	1661637±77320b
67	(S)-5'-脱氧-5' -（甲基亚磺酰基）腺苷 (S)-5'-Deoxy-5'-(methylsulfinyl)adenosine	3129086±882862a	2919162±1223813a	1980296±688545a
68	腺苷 Adenosine*	11518652±412666a	10370580±354834b	8366365±330059c
69	鸟苷 Guanosine*	2390845±190284a	2035461±70401b	1463535±89231c
70	5'-甲硫腺苷 5'-Methylthioadenosine	3089992±571947a	3567162±597102a	3150748±579503a
	酚酸 Phenolic acids
71	茶没食子素 Theogallin*	25899247±573438a	31559584±533807b	50027889±838726c
72	木麻黄素 Strictinin*	1774131±71441a	1958248±182106a	3045129±305136b
73	4-香豆酰奎宁酸 4-Coumaroylquinic acid	1490324±342313a	1610962±50961a	1667523±402289a
74	绿原酸 Chlorogenic acid*	951977±26554a	1163181±36488b	1210987±22284c
75	二没食子葡萄糖苷 Digalloylglucose	54447±5062a	65531±4727b	136856±7065c
76	3-O-p-香豆酰奎宁 3-O-p-Coumaroylquinic acid	5148816±226499a	5686498±191820a	4357076±794521b
77	鲁米诺酸 Lucuminic acid	393779±42713a	428757±27110a	180194±17712b
78	咖啡酰莽草酸 Caffeoylshikimic acid	124053±3716a	71765±2542b	0±0c
79	2''-O-反式香豆酰紫云英苷2''-O-trans-p-Coumaroylastragalin	315833±14488a	427880±10136ab	481791±180927b
	其他 Others
80	胆碱磷酸 Phosphocholine	996444±32181a	1102106±31318b	2057178±51259c
81	甘油磷酸胆碱 Glycerophosphocholine	3593165±298005a	1005165±240471b	689645±68058c
82	N-乳酰乙醇胺 N-Lactoyl ethanolamine	1479644±40550a	1231846±44941b	956384±48087c
83	茶氨酸葡萄糖苷 Theanine glucoside	1570632±195849a	1325741±40281b	1732060±143831a
84	1-乙基-5-羟基-2-吡咯烷酮1-Ethyl-5-hydroxy-2-pyrrolidinone*	2415457±132124a	2761946±73300b	2371416±94210a
85	泛酸 Pantothenic acid	307404±16208a	262262±7379b	236161±10922c
86	二氢猕猴桃内脂 Dihydroactinidiolide	199672±27481a	226319±14022b	135856±6966c
87	N, N'-二环己基脲 N,N'-Dicyclohexylurea	3100145±55344a	3096187±43286a	3041915±59904a

表2

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	对照CK	中度遮阴（M）Moderate shading	黑暗遮阴（D）Dark shading
总多酚 Total polyphenols (%)	9.99±0.4a	9.77±0.71a	12.75±0.57b
总氨基酸 Total amino acids (%)	4.63±0.14a	4.20±0.05b	4.33±0.06b
总黄酮 Total flavonoids (%)	3.28±0.17a	2.17±0.06b	1.46±0.14c
酚氨比Ratio of polyphenols to amino acids	2.16±0.05a	2.33±0.17a	2.95±0.17b
没食子酸Gallic acid (mg?g^-1)	3.78±0.22a	4.51±0.29b	4.63±0.11b
表没食子儿茶素 EGC (mg?g^-1)	14.93±0.37a	13.49±0.08b	10.56±0.34c
儿茶素 C (mg?g^-1)	4.19±0.13a	3.99±0.03b	8.24±0.08c
表没食子儿茶素没食子酸酯EGCG (mg?g^-1)	29.12±3.86a	28.35±2.7a	53.38±6.08b
表儿茶素EC (mg?g^-1)	6.42±0.05a	5.58±0.07b	5.64±0.12b
表儿茶素没食子酸酯ECG (mg?g^-1)	2.19±0.63a	1.79±0.37a	5.69±1.12b
咖啡碱Caffeine (mg?g^-1)	26.93±0.87a	28.88±0.08b	39.4±0.19c
含水率Moisture content (%)	78.67±0.13a	80.15±0.28b	80.85±0.25c