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Essential oil composition of Hypericum L. species from Southeastern Serbia and their chemotaxonomy

Essential oil composition of Hypericum L.species from

Southeastern Serbia and their chemotaxonomy

Andrija Smelcerovic a ,Michael Spiteller a ,*,Axel Patrick Ligon a ,

Zaklina Smelcerovic a ,Nils Raabe b

Institute of Environmental Research,University of Dortmund,Otto-Hahn-Str.6,44221Dortmund,Germany

Department of Statistics,University of Dortmund,Vogelpothsweg 87,44221Dortmund,Germany

Received 25March 2005;accepted 16September 2006

Abstract

The essential oils of the aerial parts of nine species of Hypericum (Hypericum barbatum ,Hypericum hirsutum ,Hypericum li-narioides ,Hypericum maculatum ,Hypericum olympicum ,Hypericum perforatum ,Hypericum richeri ,Hypericum rumeliacum and Hypericum tetrapterum ),collected from different locations in Southeast Serbia,were obtained by steam distillation and ana-lyzed by GC and GC e MS.The essential oils investigated were characterized by a high content of non-terpene compounds and a low content of monoterpenes.The contents of non-terpenes,monoterpenes and sesquiterpenes in oils of the species H.barbatum ,H.richeri and H.rumeliacum (section Drosocaprium )were similar and these oils were characterized by high contents of fatty acids.The oils of H.hirsutum and H.linarioides (section Taeniocarpium )contained a high percentage of n -nonane.There were similar-ities in contents of non-terpenes and sesquiterpenes in oils of species that belong to the section Hypericum (H.maculatum ,H.per-foratum and H.tetrapterum ).The oil of H.olympicum differed from others by higher terpene content.A comparison was also carried out of the chemical composition of the essential oils from ?ower,leaf and stem of H.perforatum and it revealed that the highest concentration of non-terpene compounds was found in the ?ower and stem oil,while a high concentration of sesqui-terpenes was characteristic for leaf oil.There were signi?cant differences in the concentrations of the same compounds in the es-sential oils of H.maculatum ,H.olympicum and H.perforatum ,collected in different years from the same location which could be explained by seasonal differences.All data were statistically processed with principal component analysis and cluster analysis.The main conclusion from the above data is that genetic and environmental factors both play a role in determining the composition of essential oils of the Hypericum species studied.ó2006Elsevier Ltd.All rights reserved.

Keywords:Hypericum barbatum ;Hypericum hirsutum ;Hypericum linarioides ;Hypericum maculatum ;Hypericum olympicum ;Hypericum perfo-ratum ;Hypericum richeri ;Hypericum rumeliacum ;Hypericum tetrapterum ;Essential oil composition

*Corresponding author.Tel.:t492317554080;fax:t492317554085.E-mail address:m.spiteller@infu.uni-dortmund.de (M.Spiteller).0305-1978/$-see front matter ó2006Elsevier Ltd.All rights reserved.doi:10.1016/j.bse.2006.09.012

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Biochemical Systematics and Ecology 35(2007)99e

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100 A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

1.Introduction

Hypericum L.is a genus of about400species,widespread in warm-temperature areas throughout the world and well represented in the Mediterranean area(Robson and Strid,1986).Plants of the genus Hypericum have tradition-ally been used as medicinal plants in various parts of the world(Yazaki and Okada,1994).Hypericum perforatum occupies a special position among the species of Hypericum.The chemical composition of H.perforatum oil has been the subject of many publications(Cakir et al.,1997;Baser et al.,2002;Osinska,2002;Schwob et al., 2002a;Mockute et al.,2003;Smelcerovic et al.,2004).The content of the oil depends on the origin of the plant. Thus,a-pinene was the most abundant component of the oil of H.perforatum from Turkey(61.7%)(Cakir et al., 1997)and b-caryophyllene of the oil from Uzbekistan(11.7%)(Baser et al.,2002).The two monoterpenes (a-and b-pinene)made up to70%of the leaf essential oil of H.perforatum from India(Weyerstahl et al.,1995). The H.perforatum oils from Lithuania have been classi?ed into three chemotypes:b-caryophyllene,caryophyllene oxide and germacrene D(Mockute et al.,2003).Considerable variation has already been reported in oil composition among different populations of H.perforatum from Serbia(Mimica-Dukic et al.,1997).The essential oil content of many other Hypericum species has been described:Hypericum androsaemum(Guedes et al.,2003),Hypericum brasiliense(Abreu et al.,2004),Hypericum coris(Schwob et al.,2002b),Hypericum dogonbadanicum(Sajjadi et al.,2001),Hypericum foliosum(Santos et al.,1999),Hypericum heterophyllum(Cakir et al.,2004),Hypericum hircinum(Bertoli et al.,2000),Hypericum hyssopifolium(Cakir et al.,2004),Hypericum lanceolatum(Vera et al., 1996),Hypericum linarioides(Cakir et al.,2005),Hypericum maculatum(Vasilieva et al.,2003),Hypericum perfo-liatum(Couladis et al.,2001),Hypericum richeri(Ferretti et al.,2005),Hypericum rumeliacum(Couladis et al., 2003),Hypericum scabrum(Cakir et al.,1997;Baser et al.,2002),Hypericum triquetrifolium(Bertoli et al., 2003).The?ora of Serbia lists19species of Hypericum(Josifovic,1972).Recently,the chemical composition has been determined of the essential oils of Hypericum atomarium(Gudzic et al.,2004),H.maculatum(Gudzic et al.,2002),Hypericum olympicum(Gudzic et al.,2001)and H.perforatum(Gudzic et al.,2001;Smelcerovic et al.,2004),all originating from Southeastern Serbia.

The objective of this study was to determine the essential oil composition of nine wild-growing species of Hyper-icum(H.barbatum,H.hirsutum,H.linarioides,H.maculatum,H.olympicum,H.perforatum,H.richeri,H.rumelia-cum and Hypericum tetrapterum)from the Southeastern region of Serbia and to examine their potential chemotaxonomic signi?cance.The chemical composition of oils obtained from?ower,leaf and stem of H.perforatum and of the oils of H.maculatum,H.olympicum and H.perforatum collected in years1998,2001and2003are also discussed.

2.Materials and methods

2.1.Plant material

Table1contains information concerning the species of Hypericum studied,the voucher numbers of the specimens deposited in the herbarium(Herbarium Moesicum Doljevac,Serbia and Montenegro),the site and date of collection, together with their taxonomic placement within sections of the genus Hypericum(Robson,1977).All the plant samples were collected at bloom stage.Dried and ground drug was steam distilled for2.5h using a Clevenger apparatus.

2.2.Identi?cation procedure

The oils were analyzed by analytical GC and GC e MS.Constituents were identi?ed by comparison of their reten-tion times with standards and/or their mass spectra with those from the NIST MS library(Version2.0a),Wiley MS library(Version6)and the literature(Adams,1989,1995).The fatty acids and their methyl esters were identi?ed by methylation of the essential oils.The solutions of essential oils in2-propanol were derivatized with trimethylsul-fonium hydroxide to yield the methyl esters of the fatty acids(V osman et al.,1998;Ishida et al.,1999).The coherence of the retention indexes of the analyzed compounds with the retention indexes obtained with a DB-5column(Adams, 1989,1995)constituted an additional criterion in the con?rmation of each compound.

2.2.1.Analytical GC

A Thermo Finnigan Trace Gas Chromatograph,equipped with a fused silica capillary column (DB-530m ?0.25mm ?0.25m m)and FID was used.The operating conditions were:temperature program,60e 320 C at 10 C/min and 320 C (4min);injector temperature,310 C;detector temperature,320 C;carrier gas helium (1mL/min);and split mode (1:25).

2.2.2.GC e MS

Analyses were performed on a Thermo Finnigan Trace Gas Chromatograph and Trace MS PLUS detector,equipped with a fused silica column (DB-530m ?0.25mm ?0.25m m);carrier gas helium (1mL/min)with the same temper-ature program as for the analytical GC.Ionization was performed at 70eV .Oil solutions were injected in two split modes (1:10and 1:20).2.3.Data analyses

All data were statistically analyzed using statistical Software R (Foundation for Statistical Computing,Vienna,Austria,2005,ISBN 3-900051-07-0).Analyses included principal component analysis and cluster analysis.2.3.1.Principal component analysis

A two-dimensional visualization of the position of the exemplars relative to each other was created by depicting the values of the ?rst two principal components.The principal components are the axes of that orthogonal projection for which the values of the ?rst axis have the highest possible variance,and those of the second have the second highest and so on (Hartung and Baerbel,1999).

2.3.2.Cluster analysis

For a clearer arrangement the compounds measured were grouped in a manner that assigned similar behaving,i.e.highly correlated compounds to the same groups.The hierarchical cluster analysis method ’’average linkage’’has been applied to achieve such a grouping (Buttler,2000).

Table 1

Species of Hypericum from Southeast Serbia studied Section a

Code b Plant species

V oucher number(HMD c )Collection period Locality

Drosocarpium Spach.

A 2003H.barbatum Jacq.705July 2003Rtanj

B 2003H.richeri Vill.

715August 2003Suva planina C 2003H.rumeliacum Boiss.717July 2003Rujan planina Hypericum

D 2003H.maculatum Crantz 711July 2003Stara planina D 2001H.maculatum Crantz.701June 2001Vlasina D 1998H.maculatum Crantz.

e July 1998Vlasina

E F2004Flower of H.perforatum L.728June 2004Pasina cesma E L2004Leaf of H.perforatum L.728June 2004Pasina cesma E S2004Stem of H.perforatum L.728June 2004Pasina cesma E 2003H.perforatum L.714July 2003Rujan planina E 2001H.perforatum L.703June 2001Rujan planina E 1998H.perforatum L.e July 1998Rujan planina

F 2003H.tetrapterum Fries.722August 2003Beljanica Taeniocarpium Jaub.et Spach.

G 2003H.hirsutum L.

708August 2003Suva planina H 2003H.linarioides Bosse.709August 2003Suva planina Olympia (Spach.)Nyman

I 2003H.olympicum L.713July 2003Rujan planina I 2001H.olympicum L.702June 2001Rujan planina I 1998

H.olympicum L.

July 1998

Rujan planina

a Taxonomic classi?cation according to Robson (1977).

b This is the code used for identifying samples studied in Tables 2e 4.c

Herbarium Moesicum Doljevac (Serbia and Montenegro).

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102 A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

3.Results and discussion

3.1.Essential oil composition of nine species of Hypericum

The compositions of the oils isolated from nine species of Hypericum are reproduced in Table2.The oils were complex mixtures of non-terpenes,monoterpenes and sesquiterpenes:98components were identi?ed in nine essential oils under study.

The non-terpene compounds made up the higher contribution(43.5%)in the essential oil of H.barbatum(Table2, code A2003).The content of two fatty acids(hexadecanoic and octadecadienoic)amounted to18.0%.The sesquiter-penes amounted to28.3%with hydrocarbons dominating(19.7%).The monoterpenes amounted to12.7%and the content of oxygenated monoterpenes was relatively low amounting to2.3%.

The sesquiterpenes made up the highest contribution(41.2%)in the essential oil of H.richeri(Table2,code B2003), and the oxygenated sesquiterpenes amounted to24.9%.The monoterpenes amounted to7.3%.

The content of three fatty acids(dodecanoic,tetradecanoic and hexadecanoic)amounted to27.0%in the essential oil of H.rumeliacum(Table2,code C2003).The sesquiterpene hydrocarbons amounted to26.5%and the content of oxygenated sesquiterpenes was7.7%.The monoterpene fraction was relatively small(4.2%).

The content of non-terpene compounds amounted to48.2%in the essential oil of H.maculatum(Table2,code D2003).The content of sesquiterpene hydrocarbons amounted to9.4%and the content of oxygenated sesquiterpenes was20.9%.

In the essential oil of H.perforatum(Table2,code E2003)the contents of non-terpenes,monoterpenes and sesqui-terpenes compounds amounted to44.1,19.8and23.4%,respectively.The oxygenated monoterpenes amounted to 1.9%.The sesquiterpenoid fraction contained the highest proportion of oxygenated compounds(17.8%).

In the essential oil of H.tetrapterum(Table2,code F2003)the contents of non-terpenes,monoterpenes and ses-quiterpenes amount to32.3,4.0and26.4%,respectively.The content of the hydrocarbons(11.6%)and oxygenated compounds(14.8%)was similar in the sesquiterpenoid fraction;while monoterpene hydrocarbons were not detected.

The major components in the essential oil of H.hirsutum(Table2,code G2003)were n-nonane and n-undecane amounting to52.3%.The sesquiterpene hydrocarbons amounted to7.9%and the oxygenated sesquiterpenes amounted to5.1%.A low content of monoterpenes(0.5%)and a high content of n-nonane(40.5%)were the charac-teristics of this sample.

In the essential oil of H.linarioides(Table2,code H2003)the content of non-terpenes,monoterpenes and sesqui-terpenes in the oil sample amounted to40.1%,18.2%and18.1%,respectively.Hydrocarbons(10.6%)and oxygenated compounds(7.5%)in the sesquiterpenoid fraction did not differ much.Hydrocarbons predominated in the monoter-penoid fraction(15.6%).

The sesquiterpenes formed the main fraction in the essential oil of H.olympicum(Table2,code I2003)that amounted to47.7%and the content of hydrocarbons(23.9%)and oxygenated compounds(23.8%)was almost iden-tical.The content of monoterpenes amounted to10.7%.

The content of the non-terpene and terpene compounds was similar in the majority of oils particularly those from

H.barbatum,H.linarioides,H.perforatum,H.rumeliacum and H.tetrapetrum.Terpenes made up the main fraction

(58.4%)in the oil of H.olympicum.The oil of H.hirsutum contained the lowest amount of terpene compounds (13.5%).

All oil samples exhibited a relative low content of monoterpenes.Their content ranged from0.5%(H.hirsutum)to 19.8%(H.perforatum).This was in agreement with previous data on the content of monoterpenes in Hypericum oils of Serbian origin(Mimica-Dukic et al.,1997;Gudzic et al.,2001,2002;Smelcerovic et al.,2004).

Diterpenes were found in only three oil samples in this study:H.richeri(1.8%)and H.rumeliacum(1.1%),and H.tetrapterum(0.1%)which contrasts to earlier results of the investigation of oils of Hypericum species from South-eastern region of Serbia that did not reveal the presence of any diterpenes at all(Gudzic et al.,2001,2002,2004;Smel-cerovic et al.,2004).

A great variability was found in the oil composition of species investigated in this work.Thus,n-nonane was the major component in H.hirsutum and H.maculatum oils,a-pinene in H.linarioides oil,germacrene D in H.olympicum oil,2-methyl-octane in H.perforatum oil and(E)-anethol in H.richeri oil.On the other hand,n-nonane was not found in H.olympicum and H.rumeliacum oils and a-pinene in H.tetrapterum oil.Germacrene D was found in

Table 2

Compositions of the essential oils of nine species of Hypericum (value given in %weight fraction)Constituents

Identi?ed by Drosocarpium

Hypericum

Taeniocarpium

Olympia A 2003B 2003C 2003D 2003E 2003F 2003G 2003H 2003I 20032-Methyl-octane 858a,b e 1.4e 1.220.5e e e 6.1n -Nonane 897a,b 3.07.9e 14.9 1.60.640.510.6e a -Pinene 941a,b 4.7 4.40.8 2.213.7e 0.211.5 4.6Camphene

953a 0.2e e e e e e 0.2e 3-Methyl-nonane 967a e 0.7e 1.0 2.0e e 0.60.1b -Pinene

982a,b 4.6 1.1 1.50.4 3.5e e 1.4 2.16-Methyl-5-hepten-2-one 984a e e e e e 1.5e 2.3e cis -Meta-mentha-2,8-diene 993a e e e e e e e 0.6e n -Decane 996a,b e e e e e e 0.7e e n -Octanal 999a,b e e e e e e 0.3e e Unknown 1026e e 0.60.50.5 1.3e e e 0.5Limonene 1034a,b 0.9e e e 0.4e e 1.5 1.1(Z )-b -ocimene 1045a e e e e 0.3e e 0.4e g -Terpinene 1062a e 0.6e 0.3e e e e e 2-Methyl-decane

1068a e e e e 1.7e e e 1.12,6-Dimethyl-3,5-heptanedione 1076a e e e e e 7.6e e e 2-Nonanone 1090a,b e e e e e e 1.0e e Methyl benzoate 1094a,b e 0.4e e e e e e e 2-Nonanol 1097a,b e e e e e e 1.7e e n -Undecane 1103a,b 2.9 2.00.9 5.90.8 1.511.8 3.80.9Linalool 1105a 1.00.40.4e 1.0 3.4e 2.6 1.1n -Nonanal

1107a,b e e e e e 0.10.6e e a -Campholenal

1133a e e e e 0.9e e e e 2,2,6-Trimethyl-hepta-3,5-diene 1161a e e e e e 0.9e e e n -Octanoic acid 1166a,c e e 0.5e e e e e e 4-Terpineol 1187a 0.40.40.50.6e 0.2e e 0.3a -Terpineol 1202a 0.90.2 1.00.4e 0.40.3e 0.6Dihydro carveol 1205a e 0.2e e e e e e e Geraniol

1256a e e e e e e e e 0.92-Methyl-dodecane 1261a 1.0e 0.6e 0.4e e e e n -Nonanoic acid 1269a,c 0.30.40.7e e 1.2 1.1e e 3-Undecanone 1283a e e e e e e 0.5e e (E )-anethole 1285a,b e 9.5e e 6.0e e e 2-Undecanone 1288a,b e e 0.20.5e e 1.6e e n -Tridecane

1293a,b 1.1e e e e e e e e (E ,E )-2,4-decadienal 1314a e e e e e e 0.9e e a -Cubebene 1350a e e 0.2e e e e e 0.1a -Longipinene 1355a 1.70.4 1.9e 0.2e 1.4e e n -Decanoic acid 1358a,c e e 0.40.3e 1.1e e 0.2n -Octadecanal 1361a e e e e e e 0.1e e a -Yalangene 1372a e e e 0.2e 0.7e e 0.1a -Copaene 1375a 1.00.40.60.30.2e 0.4e 0.5n -Dodecanal 1392a,b e e 2.10.6e 0.2e e e Unknown 1417e e e 1.1e e 15.5e e e b -Cedrene

1423a e e e 0.4e 1.6e e 1.4b -Caryophyllene 1424a,b 3.8 1.8 5.8 1.4 3.00.7e 0.6 1.3b -Copaene 1435a 0.7e e e e e e e e (Z )-b -farnesene 1442a 2.80.5 2.70.70.2e e 2.5 2.6a -Himachalene 1455a e 0.6e e e e e e e allo-Aromadrene 1460a 0.8 1.0 1.1e e e 3.80.6 1.510-epi -Italicene 1462a e 0.9e e 1.0e e e g -Muurolene 1473a 3.7 3.1 3.0 1.60.9 1.90.9 1.20.9g -Himachalene 1476a e 1.2e e e 1.3e e e Germacrene D 1479a e e 4.80.70.4e e e 7.6Unknown 1493e e e e e e 6.4e e e a -Muurolene 1496

0.8

1.4

0.2

0.3

1.7

(continued on next page )

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A.Smelcerovic et al./Biochemical Systematics and Ecology 35(2007)99e 113

Table2(continued)

Constituents RI Identi?ed

by Drosocarpium Hypericum Taeniocarpium Olympia A2003B2003C2003D2003E2003F2003G2003H2003I2003

d-Cadinene1514a0.5 2.1 1.3 1.10.3 1.20.70.8 2.3 Cadina-3,9-diene1520a 1.1 3.8 2.80.90.4 3.1e 1.9 3.9 Cadina-1,3,5-triene1528a 2.80.6e 1.9e0.10.7e e a-Bisabolene1536a0.8e e e e e e 2.7e Nerolidol1556a e 1.3e e 1.8e e e e n-Dodecanoic acid1562a,c 1.4e8.0 1.8e 1.3 1.3 1.3 1.6 3-Hexenyl-benzoate1570a0.7e e e0.6e e 1.00.5 Spathulenol1575a 3.7 1.1 1.97.09.8 2.6 2.9 2.5 6.9 Caryophyllene oxide1582a,b 2.17.1 2.4 1.5 2.9 3.2 2.0 1.7 1.0 Sesquiterpene C15H24O1592a e0.6e e e 1.3e e e Globulol1599a,b e9.40.68.00.3 6.1e e 5.5 12-Methyl-tridecanol1625a e e 2.3e 3.7e e e e 1,10-di-epi-Cubenol1633a e0.3e e e e e e e epi-a-Cubenol1635a0.3e e e e0.5e0.20.9 epi-a-Cadinol1644a0.50.20.80.7e0.30.20.90.4 epi-a-Muurolol1647a0.2 1.30.40.7e e e0.30.3 3,6-Pentadecadienal1651a e e e e e0.5e e 2.5 a-Cadinol1657a 1.3 3.6 1.6 3.0e0.8e0.5 6.1 Caryophylla-3(15),7-dienol(6)I1664a0.5e e e 1.7e e0.5e n-Tetradecanol1670a,b e e0.3e 2.8e e e e Caryophylla-3(15),7-dienol(6)II1682a e e e e 1.3e e e e a-Bisabolol1684a e e e e e e e0.9 2.7 Unknown1699e e 2.0e e e e e e e n-Tetradecanoic acid1748a,b,c0.30.87.3 1.40.4 1.1 1.3e0.5 Benzyl benzoate1769a,b 2.7e e 1.10.2e e 2.2 1.5 Hexahydrofarnesyl aceton1842a 2.70.7 1.50.80.90.90.6 3.90.7 n-Pentadecanoic acid1856a,b,c e e e e e0.1e e e n-Hexadecanol1873a,b e e e e 1.2e e e e n-Nonadecane1888a,b0.30.80.50.40.20.8e0.2e n-Hexadecanoic acid,

methyl ester

1907a,c e0.20.40.3e e e e e

n-Hexadecanoic acid1968a,b,c8.0 6.211.79.2 4.0 4.1 3.1 2.6 6.5 Ethyl hexadecanonate1981a e e e e e e e e e n-Eicosane1993a,b e0.10.30.1e0.2e0.1e Kaurene2071a e e e e e0.1e e e (Z,Z)-9,12-octadecadienoic acid,

methyl ester

2091a,c e e e e e0.1e e e n-Heneicosane2099a 1.00.5 1.20.60.60.70.10.80.2 (E)-phytol2111a,b e 1.8 1.1e e e e e e (Z,Z)-9,12-octadecadienoic acid2146a,c10.0 2.4 1.3 1.1e0.70.8 3.3 1.7 (Z,Z,Z)-9,12,15-octadecatrienoic acid,methyl

ester

2158a 1.9 1.0 2.8 3.5e0.70.10.30.7

n-Docosane2199a,b0.5e0.20.1e t e0.1t

n-Tricosane2304a0.60.40.60.60.40.20.20.70.6 n-Tetracosane2399a,b t e0.10.1e e0.20.10.1 n-Pentacosane2504a0.60.40.50.50.30.10.2 1.00.4 n-Hexacosane2597a,b0.1e0.1e e e e0.2e n-Heptacosane2706a 1.60.3e0.60.4t0.2 2.40.5 n-Octacosane2797a,b0.2e e e t e0.30.4e n-Nonacosane2902a 2.60.70.7 1.6 1.40.10.4 2.2 1.9 Total84.589.786.382.988.684.783.176.487.2 RI?calculated retention indices.

a?identi?cation based on comparison of mass spectra.

b?retention time identical to authentic compounds.

c?identi?cation based on methylation.

t?less than0.1%.

The codes are given in Table1.

104 A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

H.maculatum ,H.olympicum ,H.perforatum and H.rumeliacum oils,2-methyl-octane in H.maculatum ,H.olympi-cum ,H.perforatum and H.richeri oils and (E )-anethol in H.richeri and H.tetrapterum oils.

The oils studied had 11common components.All nine oil samples contained spathulenol and caryophyllene oxide;this is in agreement with the literature report on essential oils of H.perforatum growing wild in ten habitats in Lith-uania (Mockute et al.,2003).

It is interesting that there were also signi?cant differences in the oil composition of samples collected from the same location (Tables 1and 2;locality Suva planina,codes B 2003,G 2003and H 2003;and locality Rujan planina,codes C 2003,E 2003and I 2003),which suggest that genetic factors play a role in determining the oil composition.Our results are in agreement with the previous study of H.olympicum and H.perforatum oils (Gudzic et al.,2001)https://www.wendangku.net/doc/e04500825.html,positions of the ?ower,leaf and stem oils of Hypericum perforatum

The composition of oils isolated from ?owers (code F F2004),leaves (code F L2004)and stems (code F S2004)of H.perforatum ,are presented in Table 3.Signi?cant differences were observed in the chemical composition of oils of various parts of the plant.

The non-terpene compounds were the major fraction of the oil obtained from ?owers and they amounted to 44.4%.A high content of sesquiterpenes (73.8%)and low content of non-terpenes (10.6%)characterized the leaf oil.The con-tent of non-terpene in the stem oil amounted to 50.4%.

The chemical composition of the leaf essential oil of H.perforatum investigated in this study differed from the leaf essential oil of H.perforatum originating from India (Weyerstahl et al.,1995).a -Pinene was the major component of the leaf oil from India (67.3%),while its content in the leaf oil from Southeastern Serbia was considerably lower (1.2%).Germacrene D was the main component in the leaf oil from Southeastern Serbia,which was not the case of the leaf oil from India.On the other hand,there were similarities in the composition of leaf oil of H.perforatum investigated in this study and the oils of H.perforatum from Lithuania (Mockute et al.,2003).All these oils were char-acterized by high contents of b -caryophyllene,germacrene D and caryophyllene oxide.

3.3.Variability of chemical compositions of oils of Hypericum maculatum,Hypericum olympicum and Hypericum perforatum collected in years 1998,2001and 2003

Published data are available on the essential oil compositions of H.maculatum ,H.olympicum and H.perforatum ,collected in 1998(Gudzic et al.,2001,2002)and in this study the composition of oils of the same species from the same locations collected in 2001and 2003were determined so that a comparison was possible over a longer period of time.The results are summarized in Table 4and the signi?cant differences in the amounts of the same compound in samples from different years are evident.

A high content of the sesquiterpenes (61.0%)characterized the H.maculatum oil of the year 1998(Gudzic et al.,2002).The content of non-terpenes compounds were relatively high in the H.maculatum oils of years 2001(56.0%)and 2003(48.2%).There were 11common components in H.maculatum oils collected in different years.

Sesquiterpenes were the main fraction of the H.olympicum oils and amounted to 47.7%,74.5%and 56.0%in the oils collected in 2003,2001and 1998,respectively.The major component in the H.olympicum oil of the year 1998was (E )-anethole (30.7%)(Gudzic et al.,2001).It was not found in the H.olympicum oils of years 2001and 2003.These samples contained 18common components.

2-Methyl-octane was the main constituent of the H.perforatum samples collected in years 2003(20.5%)and 1998(13.1%),while its content in the H.perforatum sample of the year 2001was lower (3.1%).a -Pinene and b -pinene amounted to 17.2%in the oil of the year 2003,while their content in oils of the years 2001and 1998was 3.8%and 2.2%,respectively.There were 18common components in H.perforatum oils.

The differences in the oil composition of samples collected from the same species and the same location,in dif-ferent years,might be explained by seasonal differences because the samples were collected at different dates.3.4.Chemotaxonomic signi?cance of the oils obtained from Hypericum species

An examination of Table 2reveals de?nite chemotaxonomic similarities and differences among the nine species.The contents of non-terpenes,monoterpenes and sesquiterpenes in oils of the species H.barbatum ,H.richeri and

105

A.Smelcerovic et al./Biochemical Systematics and Ecology 35(2007)99e 113

106 A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

Table3

Compositions of the?ower,leaf and stem essential oils of Hypericum perforatum(value given in%weight fraction)

Constituents RI Identi?ed by E F2004E L2004E S2004 2-Methyl-octane858a,b27.3 1.8e

n-Nonane897a,b 1.3e0.1 a-Pinene941a,b15.2 1.20.1 3-Methyl-nonane967a0.90.3e

b-Pinene982a,b 3.4 1.00.4 a-Terpinene1019a e0.2e Unknown1026e e0.50.3 b-Phellandrene1034a e0.3e (Z)-b-ocimene1045a 2.70.3e

g-Terpinene1062a e0.6e

2-Methyl-decane1068a 1.5e e 2,6-Dimethyl-3,5-heptanedione1076a e e 2.4 n-Undecane1103a,b0.6e 1.2 Linalool1105a0.10.9 1.0 4-Terpineol1187a0.50.9e

a-Terpineol1202a0.30.4e Dihydro carveol1205a e0.4e Carvone1245a e e 1.2 (Z)-anethole1250a e e0.2 2-Methyl-dodecane1261a0.6e e (E)-anethole1285a,b e e25.0 d-Elemene1342a e 1.7e

a-Cubebene1350a0.10.50.2 n-Octadecanal1361a0.2e e

a-Yalangene1372a0.10.1e

a-Copaene1375a0.4 1.10.5 b-Bourbonene1383a e 1.1e Unknown1417e e e 5.2 b-Caryophyllene1424a,b 5.0 5.5 2.4 b-Copaene1435a e 1.6e Aromadendrene1439a e 2.8e (Z)-b-farnesene1442a 3.2 3.50.6 allo-Aromadrene1460a e 2.00.4 10-epi-Italicene1462a e e0.5 n-Dodecanol1470a,b e 1.4e

g-Muurolene1473a 1.6 4.3 2.1 a-Bergamotene1475a e11.5e

g-Himachalene1476a0.9e 2.3 Germacrene D1479a 1.710.0e Unknown1493e e e 2.7 a-Muurolene1496a e0.9e

d-Cadinene1514a0.8 3.2 1.0 Cadina-3,9-diene1520a 1.4 4.7 1.9 Cadina-1,3,5-triene1528a0.20.30.1 Nerolidol1556a 1.5 1.9 1.5 3-Hexenyl-benzoate1570a 1.00.7e Spathulenol1575a 3.8 3.4 3.5 Caryophyllene oxide1582a,b 1.6 6.8 2.9 Sesquiterpene C15H24O1592a e0.7 1.2 Globulol1599a,b0.30.9 3.5 Humulene epoxide II1619a e 1.2e

12-Methyl-tridecanol1625a 4.3e 2.1 epi-a-Cubenol1635a e 2.60.3 epi-a-Cadinol1644a0.70.2e 3,6-Pentadecadienal1651a e e0.2 a-Cadinol1657a 1.1 1.1 1.9 n-Tetradecanol1670a,b 2.1 5.1e

a-Bisabolol1684a e0.2e

H.rumeliacum (section Drosocaprium )were similar and they were characterized with high contents of fatty acids.The oils of H.hirsutum and H.linarioides (section Taeniocarpium )contained a high percentage of n -nonane.There were similarities in contents of non-terpenes and sesquiterpenes in oils of species that belong to the section Hypericum (H.maculatum ,H.perforatum and H.tetrapterum ).The oil of H.olympicum (section Olympia )differed from others by higher terpene content.

Principal component analysis revealed that there were signi?cant differences among the compositions of the essen-tial oils of the nine species of Hypericum under study (Fig.1a),the compositions of the essential oils from ?ower,leaf and stem of H.perforatum (Fig.1b),and the compositions of the essential oils of H.maculatum ,H.olympicum and H.perforatum ,collected in different years from the same location (Fig.1c).The greatest similarity between the essential oil content and the sectional botanical classi?cation (Robson,1977)is observed for the Drosocaprium section (oils of H.barbatum (code A 2003),H.richeri (code B 2003)and H.rumeliacum (code C 2003)).The oils of H.hirsutum (code G 2003)and H.perforatum (code E 2003)are clearly distant from the oils of other seven species investigated (Fig.1a).The greatest similarity between the essential oils contents for different years between the three species investigated (H.maculatum ,H.olympicum and H.perforatum )is observed by H.perforatum (codes E 2003,E 2001,E 1998)(Fig.1c).

The dendrogram obtained by cluster analysis of the volatile metabolites of the nine species of Hypericum under study (Fig.2)suggest the existence of eight clusters (clusters I e VIII),representing principally compounds from oils of eight species (I e H.perforatum ;II e H.linarioides ;III e H.tetrapterum ;IV e H.barbatum ;V e H.rume-liacum ;VI e H.hirsutum ;VII e H.richeri ;VIII e H.olympicum ).The oil of H.maculatum alone does not form a separate cluster because it contains only two compounds whose content is highest in this species (4-terpineol and (Z ,Z ,Z )-9,12,15-octadecatrienoic acid,methyl ester).The dendrogram contains a relative range between 0.50and 0.65where no clusters are merged which suggests that the groups of characteristic compounds from oils of eight spe-cies were clearly distinguished.The species H.barbatum and H.rumeliacum belong to the section Drosocaprium ,and their clusters (IV and V)are merged in the dendrogram.No other relationship can be established between the cluster-merging and sectional botanical classi?cation (Robson,1977).

Table 3(continued )Constituents

RI Identi?ed by E F2004E L2004E S2004n -Tetradecanoic acid 1748a,b,c 0.2e 0.8Benzyl benzoate

1769a,b

0.60.3e n -Pentanoic acid,eugenyl ester 1832a e e 3.4Hexahydrofarnesyl aceton 1842a 0.40.20.6n -Pentadecanoic acid 1856a,b,c e e 0.5n -Hexadecanol

1873a,b

0.3e e Butanoic acid,2-methyl-,4-methoxy-2-(3-methyloxiranyl)phenyl ester 1882a e e 0.3n -Nonadecane

1888a,b e e 0.2n -Hexadecanoic acid 1968a,b,c 1.70.58.1Kaurene

2071a e e 0.3(Z ,Z )-9,12-octadecadienoic acid,methyl ester 2091a,c e e 0.3n -Heneicosane

2099a 0.1e 0.9(Z ,Z )-9,12-octadecadienoic acid

2146a,c

0.3e 2.1(Z ,Z ,Z )-9,12,15-octadecatrienoic acid,methyl ester 2158a 0.3e 1.6n -Tricosane 2304a t t 0.1n -Pentacosane 2504a 0.10.10.2n -Heptacosane 2706a 0.2e e n -Nonacosane 2902

a 0.40.20.1Total

91.0

91.1

88.4

RI ?calculated retention indices.

a ?identi?cation based on comparison of mass spectra.

b ?retention time identical to authenti

c compounds.c ?identi?cation base

d on methylation.t ?less than 0.1%.

The codes are given in Table 1.

107

A.Smelcerovic et al./Biochemical Systematics and Ecology 35(2007)99e 113

Table4

Variability of the essential oils compositions of Hypericum maculatum,Hypericum olympicum and Hypericum perforatum,collected in different years(value given in%weight fraction)

Constituents RI Identi?ed

by H.maculatum H.perforatum H.olympicum

D2003D2001D1998E2003E2001E1998I2003I2001I1998

2-Methyl-octane858a,b 1.229.9e20.5 3.113.1 6.1 2.7e n-Nonane897a,b14.9 3.2 1.1 1.60.4 1.4e e e Tricyclene e e e e 1.3e e e e e0.7 a-Pinene941a,b 2.212.1e13.7 2.8e 4.6 1.2e 2,5,6-Trimethyl-hepta-1,3,6-

triene

e e e e e e e e e e0.2 3-Methyl-nonane967a 1.0 3.8e 2.00.9e0.10.8e b-Pinene982a,b0.4 2.70.5 3.5 1.0 2.2 2.1 1.40.3 Myrcene e e e e e e e0.3e e0.1 n-Decane e e e e e e0.2e e e a-Phellandrene e e e e e e e e e e t

a-Terpinene e e e e e e e e e e t Unknown1026e0.5e e 1.3 1.0e0.50.3e p-Cymene e e e e0.8e e0.8e e t Limonene1034a,b e0.50.20.4e e 1.10.50.3 1,8-Cineole1036a e e0.5e0.5e e e e (Z)-b-ocimene1045a e e e0.3e e e0.2e (E)-b-ocimene e e e e e e e0.3e e0.2 g-Terpinene1062a0.3e0.4e e e e e e 2-Methyl-decane1068a e 5.3e 1.7 2.97.9 1.1 1.0e Fenchone e e e e e e e e e e0.5 Terpinolene e e e e0.2e e e e e e p-Cymenene e e e e e e e0.2e e e n-Undecane1103a,b 5.9 3.38.20.8 1.7 3.90.90.50.3 Linalool1105a e0.2e 1.0e e 1.1e e a-Thujone e e e e0.4e e e e e e a-Campholenal1133a e0.3e0.9e0.1e e e 2-Nonanol e e e e e e e0.4e e e (E)-Pinocarveol e e e e0.2e e0.4e e e Pinocarvone e e e e0.2e e0.1e e e g-Terpineol e e e e e e e e e e t

4-Terpineol1187a0.60.1 1.9e e0.50.3e e p-Cumene-8-ol e e e e e e e0.2e e e a-Terpineol1202a0.40.30.4e e0.30.6e e Myrtenal e e e e0.6e e e e e e Myrtenol e e e e0.3e e t e e e Estragole e e e e e e e e e e0.5 Cuminyl aldehyde e e e e0.2e e e e e e Carvone e e e e e e e0.1e e 4.2 Geraniol1256a e e e e e t0.9e e 2-Methyl-dodecane1261a e 2.8e0.4 5.0 4.5e0.1e (E)-anethole e e e e0.1e e0.1e e30.7 2-Undecanone1288a,b0.5e e e e e e e e n-Tridecane1293a,b e 1.00.6e 1.3 1.3e e e a-Cubebene1350a e e 1.4e e e0.1 2.1 1.3 a-Longipinene1355a e0.4e0.20.30.4e e e n-Decanoic acid1358a,c0.3e e e e e0.2e e a-Yalangene1372a0.2e0.8e e e0.10.30.6 a-Copaene1375a0.30.3 2.70.20.80.20.5 2.8 2.7 b-Bourbonene e e e e 1.0e e0.2e e0.1 b-Cubebene1388a e e0.1e e e e 1.20.7 n-Dodecanal1392a,b0.6e e e e e e e e a-Gurjunene e e e e 1.6e e e e e0.1 b-Cedrene1423a0.4e e e 1.0e 1.4e e b-Caryophyllene1424a,b 1.4 6.97.6 3.0 2.714.2 1.3 2.4 2.1 b-Copaene1435a e0.2e e e e e 3.8e 108 A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

Table 4(continued )Constituents

Identi?ed by H.maculatum H.perforatum H.olympicum D 2003D 2001D 1998E 2003E 2001E 1998I 2003I 2001I 1998b -Gurjunene e e e e 1.7e e 0.2e e 1.1Aromadendrene e e e e 0.7e e e e e e (Z )-b -farnesene 1442a 0.7 2.2e 0.2 5.8e 2.6 2.6e a -Himachalene 1455a e 0.40.4e e 0.4e e e a -Patchoulene

e e e e e e e e e e 0.5Bicyclosesquiphellandrene e e e e e e e e e e 1.8a -Caryophyllene 1458a e e 1.3e e 0.4e 2.00.3b -Farnesene e e e e 10.0e e 3.2e e 12.4allo-Aromadrene 1460a e e e e e e 1.5 2.9e a -Acoradiene e e e e 0.3e e e e e e g -Muurolene 1473a 1.60.6 5.20.9 5.6 3.50.916.17.5g -Himachalene 1476a e 0.5e e e e e e e Germacrene D 1479a 0.7e e 0.4e e 7.6 1.3 4.3Eremophyllene e e e e 1.9e e e e e 0.7a -Muurolene 1496a 0.2e 1.4e e e 1.7 3.4 1.5a -Farnesene e e e e e e e 0.1e e 0.5g -Cadinene e e e e 4.2e e 0.5e e 4.2g -Bisabolene e e e e e e e e e e t Calamenene e e e e 1.2e e e e e 0.4d -Cadinene

1514a 1.1e 7.20.3 2.70.5 2.312.68.7Cadina-3,9-diene 1520a 0.90.5e 0.4e e 3.910.00.7Cadina-1,4-diene e e e e 0.2e e e e e 0.7Cadina-1,3,5-triene 1528a 1.9e e e 2.0e e 1.5e Muurola-4,9-diene e e e e e e e e e e 0.7a -Calacorene e e e e 0.6e e e e e 0.3Germacrene B e e e e e e e e e e 0.7b -Calacorene e e e e 0.1e e e e e t Nerolidol

1556a e 1.20.8 1.8 3.80.8e e e n -Dodecanoic acid 1562a,c 1.8e e e e e 1.6e e 3-Hexenyl-benzoate 1570a e e e 0.60.60.50.50.9e Spathulenol

1575a 7.0 3.1 1.49.88.7 4.5 6.9 1.50.4Caryophyllene oxide 1582a,b 1.5 3.1 2.5 2.9 2.2e 1.00.5e Globulol 1599a,b 8.00.1 3.40.30.5e 5.50.4e Viridi?orol

e e e e 0.3e e e e e e Humulene epoxide II e e e e 0.2e e 4.2e e e 12-Methyl-tridecanol 1625a e 2.1e 3.77.5e e e e epi -a -Cubenol 1635a e e e e e 0.70.90.50.1a -Elemene e e e e e e e e e e t epi -a -Cadinol 1644a 0.7e 0.4e 0.5e 0.4 2.00.2epi -a -Muurolol 1647a 0.7e e e 0.2e 0.30.5t 3,6-Pentadecadienal 1651a e e e e e e 2.5e e a -Cadinol

1657a 3.0e 0.2e 1.5e 6.1 3.50.5Caryophylla-3(15),7-dienol (6)I 1664a e e e 1.7e e e e e n -Tetradecanol

1670a,b e 1.4e 2.87.5 4.1e e e Caryophylla-3(15),7-dienol (6)II 1682a e e e 1.30.2e e e e a -Bisabolol

1684a

e e e e e e 2.70.60.2n -Tetradecanoic acid 1748a,b,c 1.4e e 0.4e e 0.5e e Benzyl benzoate

1769a,b 1.1e e 0.20.40.1 1.5e e Hexahydrofarnesyl aceton 1842a 0.80.9e 0.9 1.9e 0.70.5e n -Hexadecanol 1873a,b e 0.4e 1.2 1.10.4e 0.4e n -Nonadecane

1888a,b 0.40.2e 0.20.20.2e e e n -Hexadecanoic acid,methyl ester

1907a,c 0.3e e e e e e e e n -Hexadecanoic acid 1968a,b,c 9.2 1.1e 4.0 2.7e 6.5e e n -Eicosane 1993a,b 0.1t e e 0.1e e e e n -Heneicosane

2099a 0.60.4e 0.60.5e 0.2t e (Z ,Z )-9,12-octadecadienoic acid

2146

a,c

1.1

1.7e

e (continued

on next

page )

109

A.Smelcerovic et al./Biochemical Systematics and Ecology 35(2007)99e 113

Table 4(continued )Constituents

Identi?ed by H.maculatum H.perforatum H.olympicum D 2003D 2001D 1998E 2003E 2001E 1998I 2003I 2001I 1998(Z ,Z ,Z )-9,12,15-octadecatrienoic acid,methyl ester 2158a 3.5e e e e e 0.7e e n -Docosane 2199a,b 0.1t e e t e t e e n -Tricosane 2304a 0.60.1e 0.40.3e 0.60.2e n -Tetracosane 2399a,b 0.1e e e e e 0.1t e n -Pentacosane 2504a 0.5t e 0.30.2e 0.4t e n -Heptacosane 2706a 0.6t e 0.40.2e 0.50.2e n -Octacosane 2797a,b e e e t e e e e e n -Nonacosane 2902

1.60.1e 1.40.6e 1.9 1.1e Total

82.9

91.7

78.9

88.6

82.9

77.6

87.2

86.5

94.0

RI ?calculated retention indices.

a ?identi?cation based on comparison of mass spectra.

b ?retention time identical to authenti

c compounds.c ?identi?cation base

d on methylation.t ?less than 0.1%.

The codes are given in Table 1

Fig.1.Principal component analysis of the volatile metabolites of nine species of Hypericum under study (a),the volatile metabolites from ?ower,leaf and stem of H.perforatum (b),and the volatile metabolites of H.maculatum ,H.olympicum and H.perforatum ,collected in different years from the same location (c).The codes are given in Table 1.

110

A.Smelcerovic et al./Biochemical Systematics and Ecology 35(2007)99e 113

Fig.2.Dendrogram obtained by cluster analysis of the volatile metabolites of nine species of Hypericum under study.111

A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

112 A.Smelcerovic et al./Biochemical Systematics and Ecology35(2007)99e113

The dendrogram obtained by cluster analysis of the volatile metabolites from?ower,leaf and stem of H.perforatum revealed that clusters representing the volatile metabolites from leaf and stem are?rst merged each other and then with clusters representing the volatile metabolites from?owers.

Dendrogram obtained by cluster analysis of the volatile metabolites of H.maculatum,H.olympicum and H.per-foratum,collected in different years from the same location,revealed that many merged clusters and individual sam-ples are not obviously separated.This result could be explained by the postulate,which indeed could be also the main conclusion of this present study that both genetic and environmental factors play a role in determining the composition of essential oils of the Hypericum species studied.

A detailed study has been performed on the secondary metabolite contents of the nine species of Hypericum under study,originating from Serbia and the F.Y.R.Macedonia(Smelcerovic and Spiteller,2006).The conclusion from the data above is that a stronger correlation exists between Robson’s sectional classi?cation(Robson,1977)and the hy-pericin and hyperforin contents of the nine Hypericum species(Smelcerovic and Spiteller,2006)in contrast to a rather low correlation with essential oil composition.Naphthodianthrones and phloroglucinol derivatives are characteristic for Hypericum species and they represent excellent chemotaxonomical markers.A phytochemical analysis and ge-netic characterisation of H.barbatum,H.hirsutum,H.linarioides,H.maculatum,H.rumeliacum and H.tetrapterum has been performed recently,showing that a correlation exists between secondary metabolite contents(hypericin, pseudohypericin,hyperforin,hyperoside and quercitrin),RAPD(random ampli?cation of polymorphic DNA)data and Robson’s sectional classi?cation among the six Hypericum species from Serbia(Smelcerovic et al.,2006). Acknowledgements

We thank Prof.Dr.N.Randjelovic,Faculty of Occupation Safety Nis,Serbia,for taxonomic identi?cation of the plant material and Prof.Dr.J.Jovanovic for critical reading of the manuscript.The Alexander von Humboldt Foun-dation,Bonn,Germany,supported the work through a fellowship to A.Smelcerovic.

References

Abreu,I.N.,Reis,M.G.,Marsaioli,A.J.,Mazzaefera,P.,2004.Essential oil composition of Hypericum brasiliens choise.Flavour Fragrance J.19, 80e82.

Adams,R.P.,1989.Identi?cation of Essential Oils by Ion Trap Mass Spectroscopy.Academic Press,San Diego.

Adams,R.P.,1995.Identi?cation of Essential Oil Components by Gas Chromatography/Mass Spectrometry.Allured Publ.Corp.,Carol Stream. Baser,K.H.C.,Oze,T.,Nuriddinov,H.R.,Demirci,A.B.,2002.Essential oils of two Hypericum species from Uzbekistan.Khim.Prir.Soedin.38, 54e57.

Bertoli,A.,Pistelli,L.,Morelli,I.,Spinelli,G.,Manichini,F.,2000.Constituens of Hypericum hircinum oils.J.Essent.Oil Res.12,617e620. Bertoli,A.,Menichini,F.,Mazzetti,M.,Spinelli,G.,Morelli,I.,2003.V olatile constituents of the leaves and?owers of Hypericum triqetrifolium Tuura.Flavour Fragrance J.18,91e94.

Buttler,G.,2000.Cluster analyse.In:V oss,W.(Ed.),Taschenbuch der Statistik.Fachbuchverlag Leipzig,Leipzig.

Cakir,A.,Duru,M.E.,Harmandar,M.,Ciriminna,R.,Passannanti,S.,Piozzi,F.,https://www.wendangku.net/doc/e04500825.html,parison of the volatile oils of Hypericum scabrum L.

and Hypericum perforatum L.from Turkey.Flavour Fragrance J.12,285e287.

Cakir,A.,Kordali,S.,Zengin,H.,Hirata,T.,https://www.wendangku.net/doc/e04500825.html,position and antifungal activity of essential oils isolated from Hypericum hysso?lium and Hypericum heterophyllum.Flavour Fragrance J.19,62e68.

Cakir,A.,Kordali,S.,Kilic,H.,Kaya,E.,2005.Antifungal properties of essential oils and crude extracts of Hypericum linarioides.Biochem.Syst.

Ecol.33,245e256.

Couladis,M.,Baziou,P.,Petrakis,P.V.,Harvala,C.,2001.Essential oil of Hypericum perfoliatum L.growing in different locations in Greece.

Flavour Fragrance J.16,204e206.

Couladis,M.,Chinou,I.B.,Tzakou,O.,Petrakis,P.V.,https://www.wendangku.net/doc/e04500825.html,position and antimicrobial activity of the essential oil of Hypericum rumeliacum subsp.apollinis(Boiss.&Heldr.).Phytother.Res.17,152e154.

Ferretti,G.,Maggi,F.,Tirillini,B.,2005.Essential oil composition of Hypericum richeri Vill.from Italy.Flavour Fragrance J.20,295e298. Gudzic,B.,Dordevic,S.,Palic,R.,Stojanovic,G.,2001.Essential oils of Hypericum olympicum L.and Hypericum perforatum L.Flavour Fra-grance J.16,201e203.

Gudzic,B.,Djokovic,D.,Vajs,V.,Palic,R.,Stojanovic,G.,https://www.wendangku.net/doc/e04500825.html,position and antimicrobial activity of the essential oil of Hypericum mac-ulatum Crantz.Flavour Fragrance J.17,392e394.

Gudzic,B.,Dordevic,S.,Nedeljkovic,J.,Smelcerovic,A.,2004.Essential oil composition of Hypericum atomarium Boiss.Chem.Ind.58,413e 415.

Guedes,A.P.,Amorim,L.R.,Vicente,A.M.S.,Ramos,G.,Fernandes-Ferriera,M.,2003.Essential oils from plants and in vitro shoots of Hyper-icum androsaemum L.J.Agric.Food Chem.51,1399e1404.

Hartung,J.,Elpelt,B.,1999.Multivariate Statistik.Oldenbourg Verlag,Mu ¨nchen.

Ishida,Y .,Wakamatsu,S.,Yokoi,H.,Ohtani,H.,Tsuge,S.,https://www.wendangku.net/doc/e04500825.html,positional analysis of polyunsaturated fatty acid oil by one-step thermally

assisted hydrolysis and methylation in the presence of trimethylsulfonium hydroxide.J.Anal.Appl.Pyrol.49,367e 376.Josifovic,M.(Ed.),1972,Flora of Serbia,vol.3.SANU,Belgrade.

Mimica-Dukic,N.,Ivancev-Tumbas,I.,Igic,R.,Popovic,M.,Gasic,O.,1997.The content and composition of essential oil of Hypericum per-foratum L.from Serbia.Pharm.Pharmacol.Lett.7,26e 28.

Mockute,D.,Bernotiene,G.,Juzdentiene,A.,2003.V olatile compounds of the aerial parts of wild St.John’s wort (Hypericum perforatum L.)

plants.Chemija 14,108e 111.

Osinska,E.,https://www.wendangku.net/doc/e04500825.html,parative study on essential oil content and its composition of different ecotypes of St.Johns wort (Hypericum perforatum

L.).Herba Pol.48,174e 177.

Robson,N.K.B.,1977.Studies in the genus Hypericum L.(Guttiferae)I.Infrageneric classi?cation.Bull.Br.Mus.Nat.Hist.(Bot.)5,293e 355.Robson,N.K.B.,Strid,A.,1986.Hypericum L.In:Strid,A.(Ed.),Mountain Flora of Greece,vol.1Cambridge University Press,Cambridge,pp.

594e 608.

Sajjadi,S.E.,Rahiminezhad,M.R.,Mehregan,I.,Poorassar,A.,2001.Constituents of essential oil of Hypericum dogonbadanicum Assadi.J.Es-sent.Oil Res.13,43e 44.

Santos,P.A.G.,Figueiredo,A.C.,Barroso,J.G.,Pedro,L.G.,Schefer,J.J.C.,https://www.wendangku.net/doc/e04500825.html,position of the essential oil of Hypericum foliosum Aiton

from ?ve Azorean islands.Flavour Fragrance J.14,283e 286.

Schwob,I.,Bessiere,J.M.,Viano,J.,https://www.wendangku.net/doc/e04500825.html,position of the essential oils of Hypericum perforatum L.from southeastern France.C.R.Bi-ologies 325,781e 785.

Schwob,I.,Bessiere,J.M.,Dherbomez,M.,Viano,J.,https://www.wendangku.net/doc/e04500825.html,position and antimicrobial activity of the essential oil of Hypericum coris .Fi-toterapia 73,511e 513.

Smelcerovic,A.,Mimica-Dukic,N.,Djordjevic,S.,2004.Essential oil composition of Hypericum perforatum L.ssp angustifolium from South

Serbia.J.Essent.Oil Bear.Plants 7,275e 278.

Smelcerovic,A.,Spiteller,M.,2006.Phytochemical analysis of nine Hypericum L.species from Serbia and the F.Y .R.Macedonia.Pharmazie 61,

251e 252.

Smelcerovic,A.,Verma,V .,Spiteller,M.,Ahmad,S.M.,Puri,S.C.,Qazi,G.N.,2006.Phytochemical analysis and genetic characterisation of six

Hypericum species from Serbia.Phytochemistry 67,171e 177.

Vasilieva,R.,Georgieva,V .,V ojnova,J.,Milkova,Ts,2003.GC e MS study on the essential oils of Bulgarian Hypericum maculatum Crantz and

Hypericum perforatum L.C.R.Acad.Bulg.Sci.56,71e 74.

Vera,R.R.,Chane-Ming,J.,Fraisse,D.J.,1996.Essential oils of Hypericum lanceolatum Lam.from Reunion.Riv.Ital.EPPOS 7,639e 644.V osman,K.,Klein,E.,Weber,N.,1998.S-methyl derivatives from thiol compounds by the pyrolytic reaction with trimethylsulfonium hydroxide.

Lipids 33,1037e 1041.

Weyerstahl,P.,Splittgerber,U.,Marschall,H.,Kaul,V .K.,1995.Constituents of the leaf essential oil of Hypericum perforatum L.from India.

Flavour Fragrance J.10,365e 370.

Yazaki,K.,Okada,T.,1994.Medicinal and Aromatic Plants VI.In:Bajaj,Y .P.S.(Ed.),Biotechnology in Agriculture and Forestry,vol.26.

Springer-Verlag,Berlin,pp.167e 178.

113

A.Smelcerovic et al./Biochemical Systematics and Ecology 35(2007)99e 113

小学生作文批改方法及步骤

小学生作文批改方法及步骤公司内部档案编码：[OPPTR-OPPT28-OPPTL98-OPPNN08]

5看文章的中心是否鲜明、集中。以上五点是写文章最低的要求。学生经过三四篇文章的批文实践，就能够掌握这几条要求了。修改后，组员再次阅读自己修改后的作文，最后抄写在课堂作文本上。第三步：各小组互改互评作文互改互评课上，各小组间交换作文。同样，在组长的带领下，对四本作文进行一一阅读、批改。 1、各小组互改的操作方法： ①格式是否正确。打开作文一看正确，拿出红笔，写上批语，格式正确；不正确的要批语指出，并修改出正确格式。比如：书信、建议书等等格式。格式不正确扣2分。 ②页面是否整洁。希望学生批改别人作文指出书面不整洁或书写不工整时，下次自己写作文也要注意，达到自己教育自己的目的。 ③修改错别字。将错字在原文处打下标记，写上正确的字。这样使粗心的同学也认真起来，批改的时候，手里抱着大字典，唯恐漏掉了错别字。发现错别字，每两个扣1分，最多扣5分。10个以上也不再多扣。 ④修改病句或语句不通。挑出病句划上横线，写出病因在何处，再在文中进行修改，每处病句减1分，减至5分，不再多减。 ⑤标点符号有明显错误。强调句号、引号、叹号、问号的使用。明显错误的地方，有一处扣1分，超过5分不再多扣。以上五条在组内时基本就解决完成，小组互换后只是再次检查并作扣分处理，一般经过第一次组内处理都比较好。

composition

3） Attention, please! I’ve something to tell you. Professor Jackson—an English disabled person will come to our school to give us a lecture from 2 to 4 o’clock on the afternoon of April 25 in Room 302, the No. 3 teaching building. His lecture is about how he smoothed away all sorts of difficulties he had met. When he was eight years old, he lost his left leg and right arm in an accident. He struggled in his life and managed to look after himself. He also achieved great success in his work. After the lecture we will have a discussion in groups on how to encourage disabled people, how to help them and how to learn from Professor Jackson. Thank you. 4) Of all the teachers, Mr Moore is the one who impresses me most. Though he is 34, he looks very young for his age. And he’s one of the most popular teachers in our school. Compared with other teachers, Mr Moore pays more attention to his way of teaching. He tries various ways to make his classes lively and interesting. In his opinion, we should not only know “what”, but also understand “why”. So, instead of giving us answers immediately, he encourages us to think by ourselves whenever he puts forward questions. With his help, we’ve learned how to analyze and settle problems. What a wonderful world of “why” he leads us to! He is such a learned person that we all admire him very much. 5） Welcome to our school. I feel it an honour to have the chance to tell you something about our school class. We have one hour activities from 4:20 to 5:20 in the afternoon. Some students read books in the reading room; some have sports on the playground; some sing songs in the theater; some learn to operate computers in the lab and others take part in their group work about different subjects. The majority are most interested in sports and computers. We hope that we can have less homework and moretime to join the activities. We are also looking forward to more visits and tour trips. Thank you. 6）Dear editor, In some places in our country the surroundings is worsening with the air filled with heavy smoke, many mountains turning deserted and rivers polluted. Waste is scattered here and there. So I strongly suggest that the government take effective measures to stop this.

小学生作文批改方法及步骤

小学生作文批改方法及步骤 Company number：【WTUT-WT88Y-W8BBGB-BWYTT-19998】

小学生作文批改方法及步骤第一步：学生自改作文学生在练习本上写完自己的作文后，自己阅读、修改自己的作文。但是，学生个人修改，往往“只缘身在此山中”，而且限于水平，文章中的毛病，作者常常自己看不出来。首先要求学生对自己的作文进行复看审核，查找出标点、错别字以及不通顺的句子，并进行改正。接着从题意、中心、内容、感情、结构、语言等方面来一个“回头望”，多问几个“是什么”或“怎么样”，对自己的作文进行从点到面，实事求是的评价。最后，对文章再次阅读，寻找出自己本次作文的最大亮点，或指出今后作文中应该改进的地方，在这样的自我修改，自我反思的过程中，学生的写作能力也在不断提高着。正如叶圣陶先生所说：“批改固教者之要务，然须进一步想，必使学生能自改其文，或文成达而竟不须改，乃有济也。” 第二步：小组内互改作文组内成员都完成作文后，在组长的带领下，针对每一个组员的作文进行一一的共同阅读，共同修改。修改时要注意： 1格式是否正确。 2找出错别字。将错字在原文处打下标记，在后面写上正确的字。 3找出病句。挑出病句划上横线，修改正确。 4标点符号。强调句号、引号、叹号、问号的使用。 5看文章的中心是否鲜明、集中。以上五点是写文章最低的要求。学生经过三四篇文章的批文实践，就能够掌握这几条要求了。修改后，组员再次阅读自己修改后的作文，最后抄写在课堂作文本上。第三步：各小组互改互评作文互改互评课上，各小组间交换作文。同样，在组长的带领下，对四本作文进行一一阅读、批改。在以前的作文批改中，我首先对所有学生的作文通览一遍，找出其中具有代表性的文章，在作文课上和学生一起进行批改。同时，注意向学生介绍规范性的批改符号，讲解具体的批改方法，从点到面，对典型作文进行全方位的改评。这样做，不但使学生学到了别人作文的长处，起到取长补短，互相促进的作用，而且也使学生学到了作文修改的方法。 1、各小组互改的操作方法： ①格式是否正确。打开作文一看正确，拿出红笔，写上批语，格式正确；不正确的要批语指出，并修改出正确格式。比如：书信、建议书等等格式。格式不正确扣2分。 ②页面是否整洁。希望学生批改别人作文指出书面不整洁或书写不工整时，下次自己写作文也要注意，达到自己教育自己的目的。酌情扣2—3分。

小学生作文的指导方法和要求

小学生作文的指导方法和要求以写人物为例说明：（引）写人，是小学作文训练的基本功之一。在记叙文中，人和事是不可分的，关键是看题目如何要求。要求写事的题目，文中的人要为事服务；要求写人的题目，文中的事必须为人服务。写人为主的记叙文，就是要通过一件或几件事，来表现人物一种或多种品质。写人的继续文，叙事不要求完整；记事的记叙文，虚实要求完整，而且要贯穿文章始终。（一）通过一件事来写人通过一件事来写人，通常是表现人物的一种品质或性格的一个方面。为了刻画人物，对所写人物必须进行必要的外貌、语言、动作、心理等方面的描写。但是，从以事写人这个角度来说，最好是选择一件最能反映此人某一特点的事，并把这件事写好。在写事情的时候，要选择典型的事例。所谓典型，就是能集中反映中心思想的事，能够表现人物的好思想、好品质、美好情感的事。对小学生来说，选择典型事例，要着眼于小事，选择那些最能反映深刻意义的小事。这样的事表面上看，都是普普通通的凡人小事，但是其中却蕴涵着深刻的意义，这就是我们常说的“小中见大”。（二）通过几件事写人可以分成两种情况：以是用几件事表现某个人的一种品质；二是用几件事表现某个人的多种品质。要注意：用几件事写人，这些事可以是完整的，作者必须把事情发生的时间、地点、人物、事件（起因、经过、结果），一一交代清楚，也可以是不完整的，只着重于某几点进行叙述。更多的是在一篇文章中，有的事详写；有的事略写；有的事要求写得比较完整，有的事要求写得比较简单。通过几件事写人，同样要对人物进行必要的外貌、行动、语言、心理的描写。（三）学会刻画人物写人的文章要会在叙事的过程中，对最能表现人物思想感情、性格特点的外貌、语言、动作、心理活动等方面进行描写，也就是学会刻画人物。 1.外貌描写也叫肖像描写，是通过对人物的容貌、神情、衣着、姿态、语调、外貌特征的描写。来揭示人物性格的一种方法。人物的的外貌和人物内心世界密切的联系，具体说：通过外貌描写，使人物的形象更丰满，能给读者留下深刻印象；通过外貌描写，揭示人物的身份；通过外貌描写，展示人物在特定场合的内心世界；通过外貌描写，表现人物性格、精神面貌和思想品质。总之，外貌描写要和表现人物特点、突出文章的中心思想紧密配合。外貌描写要传神，

中考 Composition：一模冲刺作文话题之友情

中考Composition：一模冲刺作文话题之友情作文评分标准中考作文一般从内容、语言、组织结构这三方面进行评分（总分20分）：（一）内容（满分8） 7-8分：内容切题，意思连贯，表达清楚、完整。 5-6分：内容基本切题，意思大致连贯，表达基本清楚、但不够完整。 2-4分：内容不够切题，意思不够连贯，表达不够清楚、有些离题。 0-1分：文不对题，表达不清。（二）语言（满分8）词数：每少5个单词扣0.5分，以此类推。只写出个别单词、词不成句不给分。拼写：每处错误扣0.5分，同一错误不重复计数。语法：每处错误扣0.5分，同一语法错误不重复扣分。标点符号、大小写：每两处错误扣0.5分，但扣分总和不超过1分。（三）组织结构（满分4）内容充实，上下文连贯，用语规范，表达准确，无语法错误；词汇和句型句式运用恰当，多见好句型和习惯表达用语者，可给3-4分。内容充实，不写废话，上下文连贯，用语规范，表达准确，无或少见语法错误；词汇和句型句式运用恰当，多见好句型和习惯表达用语者，可给2分。一般情况下，内容和语言累计得分在15分以上者（含），方可得到1-2分组织结构分。内容和语言在15分以下者，如文中有值得肯定的好的句型和表达，可酌情考虑给1分组织结构分。通篇句型句式单一、词汇贫乏者，即使无语法错误，一般也不予给组织结构分。

分类作文提纲一、话题：友情二、写作思路及结构： 1. 在审题时，学生要注意描写友情时，内容不能太空洞，而是要通过实例来突出某一项品质，或者对自己的影响等；以及朋友是通过哪些具体的方法帮助自己。 2. 注意使用连接词以及高级词汇，使文章逻辑清晰，内容充实；用具体的实例支撑我的观点。最后进行总结； 3. 围绕友谊可以给出一些建议或者保持友谊的秘诀。三、高频词：happiness，precious，friendship,colorful, meaningful,problems, comfort, regard, discuss, important,charming, smile, success, confident, responsibility, In my opinion,Independence,brave,encourage, experiences,succeed, difficulties, unforgettable, friendly, suggestions, helpful,understand, unbelievable, disappointed,difficult, boring, improve 四、高频短语：get ready for,learn about, by ourselves, as often as possible, face our future life,give up , make friends, get on well with,make efforts, at that time, believe in themselves, make some mistakes, makegreat progress, try my best to, communicate with, look forwards to, have someproblems with, deal with, stop them from doing it, as soon as possible, have anunforgettable experience, increase our knowledge 五、高频句型：

小学作文修改的步骤及方法

小学作文修改的步骤及方法修改作文的步骤及方法建始县实验小学姜灿俊指导作文修该是贴近学生习作实际的一次指导。学生是习作讲评的主人。为了发挥学生的主体，增强训练意识, 我尝试了以下教学方法。一.佳作展示，激发兴趣一一乐评大教育家孔子说过，'‘知之者不如好之者，好之者不如乐之者。”激发学生的兴趣，是作文教学的良好开端。为了刺激学生的表达欲望，调动学生参与的积极性，推岀四大版块“榜上有名”"佳作亮相” “片断欣赏” “出谋划策”。在“片断欣赏”让学生有感情地朗读同学的好词佳句，并配上柔和的音乐，创造一种轻松愉悦的氛围，也使学生获得成功体验，为习作的讲

评创设良好情境。二.教师对上次作文的修改进行评价、 1、精选点评，范评引路一一会评最有价值的知识是方法。为了解决这堂课的重点，让学生掌握如何修改作文的方法，我先选择一篇优秀习作，让学生欣赏、剖析，并指点写作秘诀。这使得学生在接下来的讲评、修改中有个范本。接着我采用知识迁移的的方法，让学生评析“病”例。有了之前的佳作范评，学生对“病”文的剖析就能胸有成竹。通过剖析典型作文，使学生知道什么样的作文是佳作，懂得“佳”在何处，“病”文“病”在哪里，更认识到平时要注意观察，展开联想，真情实感，遣词造句才能使作文表达更生动具体。这对学生自我评价习作有很大启发，对学生准确评价自己的习作，恰当修改自己的作文有很强的指导意义。 2、合作评改，培养能力——会改

只评不改的作文讲评课是"纸上谈兵”的空洞说教，只有让学生动手修改习作，学生才会有深切的体会，真正的领悟。叶圣陶先生说：“教师只给些引导和指点，该怎么改让学生自己去考虑去决定。”于是我给学生创设空间，通过小组合作和集体改文实践，学生在合作评改中互动交流，互相补充，循序渐进地培养了学生对自己作文进行修改的能力，达到举一反三、触类旁通的目的。三指导修改教师交代本次作文修改的重点内容，回忆本次作文的要求。指导作文修改： 1、组内评改：可以让学生先说说本次作文的要求，根据习作要求确定评改要点，然后在小组内进行作文评改，并选出组内的优秀作文。 2、全班评改：即“佳作”和“病文”评改。老师选出、二篇好文章和写得不理想的文章，师生根据本次作文的要求，针对字、词、句等进行逐一评改;

作文的具体步骤及方法

作文的具体步骤及方法小学生的语言积累还处于初级阶段，如何写作文，如何写好作文成为他们很大的一个障碍，所以如何提高质量成了他们很关注的问题。一、作文教学的序列目前国内正在实验的作文教学序列，主要有以下三种： (一)以统编教材为基础的作文教学序列统编教材的作文扣除安排在教材的“基础训练”中，与阅读教学结合穿插进行。一可分三个阶段： 1、一年级.为中年级写片断做准备阶段。通过看图说话、写话、回答问题等形式训练学生说写一句完整的话、几话连贯的话，同时学写请假条、留言条、简单的日记等应用文。 2、三年级，由说话写话向命题作文过渡阶段。要求能写记人记事和状物的简短的记叙文，要求内容具体，条理比较清楚，语句比较通顺，会用标.点，同时学写板报稿、决心书、通知等应用文。 3、四、五年级，命题作文综合训练阶段。进行记叙文写作方法和作文能力的各项训练，使学生作文逐步做到思想健康、中心明确、内容具体、条理清楚、语句通顺。同时进行一般书信、读书笔记、会议记录等应用文教学。 (二)以景山学校实验教材为基础的作文教学序列该校实行“读写结合，以作文为中心安排语文教学”，以名家名篇为典范，严格进行写作训练。一、二年级在集中大量识字的同时，突出字词句的训练进行大量造句、抄书、听写句子和段落、看图写诗写片断、写日记等练习。同时引导学生留心观察和反映周围的人、本、秆境，养成观察习惯，积累写作素材。这样，到二年级下学期，“绝大多数学生就能在教师指导下，写出三、四百字的短文，为下一段作文启蒙打好基础。三年级是作文启蒙阶段。主要采取“放胆文”的形式，把文章“写开”、“写顺”。从三年级下学期起，就指导学生围绕中，用逻辑思维去选择和组织生活中那些生动、形象、具体的材料，要使文章内容具体，叙述细致生动。四年级是掌握规律，严格训练阶段，教会学生如何写人、记事、状物等。五年级是运用规律，提高作文水平阶段，训练学生能写出夹叙夹议央抒情的儿童小品。

修改作文的步骤与方法

修改作文的步骤与方法第一步是过判断关，就是在通读文章的基础上，对主题（中心）是否突出，观点（态度）是否鲜明，所选材料是否典型，结构是否合理，层次是否清楚，详略是否得当六个方面作出判断，对要修改的文章获得总体认识；第二步是过推敲关，就是在确认文章总体框架的基础上对字、词、句、标点符号的运用作出推敲，进行修改；第三步是过润色关，就是对通过修改后的文章，再作润色。只要教师不厌其烦地强调修改步骤，学生修改作文的良好习惯就会迅速形成，修改能力也就会很快提高。无论选用哪种方法，均须从两个大的方面去努力。①是指导学生以多角度多层次多方位的思维观去思考修改的重点与方法。②是指导学生脚踏实地地进行逐字、逐词、逐句、逐层的分析修改。这样指导，不仅使学生在修改中懂得了修改方法的取舍，而且学会了运用作文批改术语评点修改作文的方法。第一步：符号示意法。所谓符号示意法，就是教师在浏览学生作文时，遵循着正确的衡文标准，顺手划下符号，以符号指导学生修改。这种批改方法，既可以把教师从繁琐的作文批改中解放出来，又可以引导学生自己动手修改文章。第二步：自改自评法。自改中，学生感到最困难的是：将内容进一步深化。这是学生修改中的障碍，教师在眉批中要善于提出问题，解开结症，插上路标，在他们感知、感受的基础上加以感情的点化，使他们再回到经历过的事件中去，再体验、再消化，以至在认识上迅速得到突破，主题自然地得到升华。文章自改后，再仔细阅读品味，并写下只言片语的感受，即自评。这种自评不要求全面，只要求真切，防止自评流于形式，或成为学生写作的累赘。第三步：自评自讲法。学生自改自评后的文章交给教师，教师根据学生的自改自评情况，选出典型，当面加以辅导，让受辅导者在班上作自评自讲。这样不仅提高了该生对作文的认识，培养了口头表达能力，强化了写作兴趣，而且也交流了写作与修改的经验，同学们听来感到亲切，易于接受。与此同时，将产生一种羡慕感、追求感。学生的自改、自评、自讲的过程，是学生作文逐渐自我完善的过程，教师要把握这一过程的规律，认真培养学生自改自评的习惯，提高学生自改的能力，使他们的文章逐渐达到“理真情切而意达”的境地。

composition作文

八年级英语上册作文复习资料 1.有很多同学早晨上学不吃早餐，这是一个不好的习惯，对身体有很大的危害。请根据提示写一篇短文，指出不吃早餐的危害。提示1.不吃早餐对身体有害 2.不吃早餐会影响上午听课。 Every morning, we have to go to school very early, so many of us don?t have breakfast. It?s very bad for our health. In the morning we usually have four clas ses. It?s a long time before lunch. If we don?t eat anything for breakfast, we may feel hungry and we can?t listen to the teacher carefully. We need energy very much while we are growing. I really think that we should have a good breakfast. 2 . How to keep healthy If we want to keep our bodies healthy, we must have a good habit. We should get up and go to bed early and sleep at least eight hours every day. Do more exercise, such as walking, swimming, playing balls and so on. We should also eat healthy food—more fruit and vegetables and less meat. If you don?t feel well, you?d better see a doctor at once. And we should wash our hands before meals and drink enough boiled water every day. It?s necessary for our health. We should not throw litter about, keep long fingernails and smoke etc. It?s also very important. 3. 从饮食，睡眠和运动几方面谈谈怎样可以保持身体健康。

composition英语作文

My favourite city My favorite city is Beijing, the capital of our country.It is in the north of China. There are more than 15 million people in Beijing, which makes the city crowded. I like eating dumplings and ducks there because they’re

very delicious. If you go to Beijing, you can visit many museums, palaces and parks there. In a word, Beijing is the most attractive city in my eye. My favorite indoor activity Of all the indoor activities,doing some

reading is my favorite. ( My favorite is doing sth.) I have got a habit of reading almost every evening before going to bed. ( I am used to reading something for 30 minutes). In my view, reading can not only enrich my knowledge, but also broaden my

作文审题步骤及方法

作文审题步骤及方法一、复旧导入上节课我们了解了作文训练一般包括五种能力的训练，看看同学们还记得吗？学生回答。对。有审题能力、立意能力、谋篇能力、表现能力、修辞能力。(ppt展示) 今天我们主要是进行审题能力的训练。作文审题分标题式命题作文审题、情景式命题作文审题、话题式作文审题、材料式命题作文命题、综合式作文审题。（课件展示）今天，我们就进行标题式命题作文审题能力的训练。（出示课件）。标题式作文的审题，看似容易，其实要真正正确、准确、明确地弄清题意，并非易事。因为文章的命题越具体，限制就必然越多越死。题中无闲字。如果一个字，一个词忽略了，弄错了，势必造成不同程度的文不对题，“偏离题意”，甚至“严重偏离题意”。那要怎样才能正确、准确、明确地分析题意呢？二、展示本节课的任务和目的通过教学，了解命题式作文的审题方法，会审题，写一篇完整的文章。三、授课过程（一）知识汇集。审题定义：审，审查，了解，斟酌，审题即写文章前仔细了解题目的含义、要求。审题，是作文的第一步。（二）、审题方法知识解析第一步：审命题的标题。 1、单词类。相对说，这类命题比较好审，只要咬文嚼字弄清词语的含义就可以了。例如：98年全国高考作文《习惯》，什么是“习惯”，词典的释义说：“习惯是指在长时期逐渐养成的，一时不容易改变的行为、倾向和社会风尚”。根据这一解释考虑，无论写一个人的某种爱好、习性，还是一个地区、一个名族、一个国家的某种传统作法、认识、习俗，都符合题意。应该注意的是，除了词的本义，还要想到它的引申义或比喻义，也就是我们平时所说的弦外之意。例如：《绿叶》《桥》《春风》等一些题目的比喻义远远大于词义的本身，以《春风》为例，它就是借用“春风送暖”的特性，给处于困难、危难之中的人或事送去的关爱、呵护、帮助。不能单纯地谈自然界之风，就偏离了题意。 2、短语类。这类命题大致有偏正、动宾、并列几种。 ①偏正结构，关键词多在偏的部分。如：《绿色的童年》，“童年”是思考的关键，选取事件一定得是童年，然后再考虑事件的性质必须是“绿色”的，也就是说必须是具有生命力旺盛、健康、纯净等特点。 ②动宾结构。其关键词多是动词。如《改造我们的学习》，题旨就是“改造”，而“学习”是改造的对象，。 ③并列结构。如：《索取与奉献》，重点在让我们阐述人生的意义在于奉献而不是索取，绝不能单纯的议论什么是“索取”、什么是“奉献”。再如，《勤奋和成功》是因果关系，《知识与能力》是相关关系，《欢乐与痛苦》是相反关系，《自尊与自强》是递进关系，只要抓住了这种关系及转化，就是抓住了主题。 3、句子类，这类题目一般是一个比较复杂的句子。审题时要抓住主谓部分的中心词或者

Composition 英语作文

Composition – description 1. 描写人物外貌和性格特征的常用词语： tall 高的，short 矮的，fat 胖的，thin瘦的，black/ blond hair 黑色的、金色的头发, big / bright eyes 大大的、明亮的眼睛，b rave 勇敢的，beautiful 美丽的，clever 机警的，ugly丑陋的，lovely可爱的，talkative健谈的，easy-going好相处的，angrily生气的， sad 难过的，happy 高兴的，excited 兴奋的，pleased 高兴的，satisfied 满意的，angry 生气的，worried 担心的，disappointed 失望的，terrified 恐惧的， friendly 友好的，smart 伶俐的，polite礼貌的， friendly友好的，foolish愚蠢的，cute可爱的，one-year-old一岁大的， be like grapes像葡萄一样的，hard-working勤劳的， honest诚实的， anxious 焦虑的，eager急切的，good-looking 长得好看的 ugly-looking 长得难看的 wise 明智的，funny-looking 长相滑稽的 ordinary-looking 长相一般的lazy 懒惰的white-haired 白头发的 warm-hearted 热心肠的healthy 健康的kind-hearted 好心的 absent-minded 心不在焉的diligent 勤奋的bad-tempered 脾气不好的 near-sighted 近视眼的far-sighted 远视眼的 pretty 漂亮的naughty 淘气的curious 好奇的，easy-going 温和宽容的 lovely 可爱的 bright 聪明的humorous 幽默的 funny 滑稽的silent 沉默的attractive 有吸引力的杏眼：almond-shaped ，小而亮的眼睛：beadlike ，美丽的: b eautiful ，大的: big/large 明亮的: bright ，眼珠突出的: bulging ，离的很近的: close-set ，深陷的: deep-socketed/deep-sunken ，梦幻般的: dreamy ，呆滞的: glazed，柔和的: gentle ，呆板的: fishlike ，凹陷的: hollow/sunken ，远视的: longsighted/farsighted ，近视的：myopic/shortsighted ，眼梢上斜的: oblique ，老花眼的: presbyopic，圆的: round ，性感的: sexy ，锐利的: sharp ，斜的: slanting ，细长的: slitty ，小的: small/tiny ，明亮的: starry，水汪汪的: watery，分的很开的: wide-spaced ，肿胀的：swollen，水灵灵的: dewy ，斜视眼的: squint， 2. 日常活动： have/ take a bath 洗澡，make the bed 整理床铺，take photos拍照， keep quiet保持安静，kick shuttlecock t踢毽子，skip跳绳， play with 玩耍，have interest in= be interested in 对。。。感兴趣， be tired of 对。。。感到厌倦、厌烦，grow up长大， make friends 交朋友，play the piano弹钢琴，go shopping逛街，购物，chat on line上网聊天，listen to music 听音乐，be fond of 喜欢， play computer games玩电脑游戏，hate 憎恨 be crazy about 对------极度喜欢enjoy 喜欢， lose interest in 对------失去兴趣

cet4 composition samples-英语作文范文赏析

How Do students Spend Their Summer Vacations In the past, summer vacations meant an escape from the academic life and a restoration to freedom. Most students enjoyed their rights of leisure to the ultimate extent. Summer vacation were made up of endless activities such as visiting friends, watching TV, fishing, touring and occasional help of housework of chores. However, the trend has changed. Currently, students are fully occupied during the summer vacation. Some are busy attending various skill training courses, trying to obtain a driving license, pass language competence tests, or challenge computer qualification tests, while others are busy seeking part-time jobs to experience an adult world. On the whole, they want to be well equipped for students to accumulate enough skills and experiences for a bright prospect but leisure-time cannot be ignored, even be omitted. Therefore, we’d better arrange summer vacations in a more flexible way. Recreation Recreations are an important part of people’s life. For example, after hours of attentive study, students feel like having a football game to relax their nerves. Workers, too, find it very satisfying to sit in front of a TV set for an hour or two when they come back from a day’s tiring work. Besides, recreations serve as a pleasing way for the retired people to pass their excessive time. Everywhere you go, you will find that during their spare time, people are engaged in recreational activities of one kind or another. Generally speaking, there are two kinds of recreations: physical activities and intellectual activities. Physical activities, on the one hand, keep one fit and develop team spirit. Basketball is a n example. On the other hand, intellectual activities such as playing chess and reading novels can train one’s brains and provide temporary escape from one’s troubles. In my opinion, there should be a balance between the two forms of activities. This is because physical activities are necessary for good health while intellectual activities are beneficial to one’s mind. Therefore, in order to make his life enjoyable, one should go in for both kinds of pastimes. A Letter to Harvard University and Apply for Administration into the MBA Program Dear Sirs, I graduated two years ago from the Department of International Trade at the University of International Business and Economics, the leading institution of business education in the people' s Republic of China. I am now applying for admission into the MBA program of your university next fall, that is, after I finish three years of being an employee in the branch company of SONY in Beijing. It is my great pleasure to have taken international trade as my major as China is expanding its trade with foreign countries. I earnestly hope I will have an opportunity to pursue graduate study at Harvard University which has a high reputation for its business education. My TOEFL score is 650 and GRE is 2038. Please send me an application form and information regarding your scholarships and assistantships.

作文修改的方法与形式

作文修改的方法与形式 A【方法】一、【减分法】要求学生从以下10个方面着手修改作文，每个方面最多扣五分。 1.格式是否正确。比如：标题是否写在第一行正中，每段开头是否空2格，是否分小段来写，应用文自身的格式遵守没有。如果格式不正确，酌情扣分。 2.卷面是否整洁。比如书写是否工整、规范，文面是否清楚、干净，有无涂抹，有无巫巴，有无破损。如果文面不整洁，酌情扣分。 3.错别字几个。发现错别字，要将错别字在原处打上叉叉，改正过来，并且写到批语中。每个错别字扣一分，本项最多扣五分。 4.有几处病句。凡病句，都要在下面画上横线，写出病因是什么，再在后面批语中，写清病句几处。每个减一分，本项最多扣五分。 5.标点符号有几处错误。发现标点符号有明显错误的地方，改正过来，一处扣一分，超出五处，不再多扣。 6.看文章的中心是否鲜明，集中。中心鲜明是说，作者赞成什么，反对什么，应该旗帜鲜明，不要模楞两可。中心集中是说，一篇文章只有一个中心，不能多中心。中心不集中通常表现在：①扣题不紧；②偏题，离题，跑题；③笔墨不集中，行文过散；④思路不明确，内容前后衔接不紧密。如果中心不鲜明，集中，酌情扣分。 7.看表达方式。主要看其是否符合文章体裁的要求，记叙文以记叙为主，说明文以说明为主，议论文以议论为主。一篇文章应该有明确的体裁，不能写成这也不像，那也不像的东西。（除此之外，还要看其是否符合作文指导的要求。）如果表达方式不符合文体要求，酌情扣分。 8.看文章的选材。这条批语提三点要求：⑴选材是否围绕中心。⑵选材是否符合生活实际。 ⑶选材是否具有典型性。 9.看文章的结构。也提三点要求：⑴层次段落是否清晰。⑵过渡是否自然。⑶开头和结尾是否照应。 10．看语言是否简练，通顺，准确。语言不简练，重复罗嗦，酌情扣分。语言不通顺，不是指有病句，而是指句与句之间衔接不连贯，也酌情扣分。二、【三过目修改法】 “三过目”修改法：第一遍以最快速度浏览全文，了解文章全貌，边看边找出错别字。第二遍逐句逐段仔细修改，写上眉批、旁批。第三遍以一目十行的速度扫视一遍，检查批阅情况，写好总评。三、【欣赏式批改法】除指出作文中明显的错误外，着重仔细寻找作文中的亮点，进行表扬。 B【形式】一、自改：学生完成作文后，随即自己进行修改。一般用“三过目修改法”和“减分法”。二、互改：同组对子间互相交换作文修改。一般用“欣赏法”和“减分法”。三、组改：同组学生一般以3人小组（abc搭配）为单位，一位书写好的学生执笔，另两名学生参与讨论，共同完成对3篇作文的修改。一般采用“减分法”和“欣赏法”。 C【注意】 1、修改的过程也是学习研究和再创作的过程，务必认真仔细，努力提高自己的写作水平。 2、要有改动的痕迹，比如：“错别字”打上叉叉，病句下面画横线，多余的词句用删除号，补充的词句用补充号。要有旁批或眉批，总评。