International Journal of

Molecular Sciences Article

Chemical Diversity, Biological Activity, and Genetic Aspects of Three Ocotea Species from the Amazon Joyce Kelly da Silva 1 , Rafaela da Trindade 1 , Edith Cibelle Moreira 2 , José Guilherme S. Maia 3 , Noura S. Dosoky 4 , Rebecca S. Miller 5 , Leland J. Cseke 5 and William N. Setzer 4, * 1 2 3 4 5

*

Programa de Pós-Graduação em Biotecnologia, Universidade Federal do Pará, 66075-900 Belém, Brazil; [email protected] (J.K.d.S.); [email protected] (R.d.T.) Instituto de Estudos em Saúde e Biológicas, Universidade Federal do Sul e Sudeste do Pará, 68501-970 Marabá, Brazil; [email protected] Programa de Pós-Graduação em Recursos Naturais da Amazônia, Universidade Federal do Oeste do Pará, 68035-110 Santarém, Brazil; [email protected] Department of Chemistry, University of Alabama in Huntsville, Huntsville, AL 35899, USA; [email protected] Department of Biological Sciences, University of Alabama in Huntsville, Huntsville, AL 35899, USA; [email protected] (R.S.M.); [email protected] (L.J.C.) Correspondence: [email protected]; Tel.: +1-256-824-6519

Academic Editors: Vincenzo De Feo, Laura De Martino and Carmen Formisano Received: 15 March 2017; Accepted: 10 May 2017; Published: 18 May 2017

Abstract: Ocotea species present economic importance and biological activities attributed to their essential oils (EOs) and extracts. For this reason, various strategies have been developed for their conservation. The chemical compositions of the essential oils and matK DNA sequences of O. caudata, O. cujumary, and O. caniculata were subjected to comparison with data from O. floribunda, O. veraguensis, and O. whitei, previously reported. The multivariate analysis of chemical composition classified the EOs into two main clusters. Group I was characterized by the presence of α-pinene (9.8–22.5%) and β-pinene (9.7–21.3%) and it includes O. caudata, O. whitei, and O. floribunda. In group II, the oils of O. cujumary and O. caniculata showed high similarity due amounts of β-caryophyllene (22.2% and 18.9%, respectively). The EO of O. veraguensis, rich in p-cymene (19.8%), showed minor similarity among all samples. The oils displayed promising antimicrobial and cytotoxic activities against Escherichia coli (minimum inhibitory concentration (MIC) < 19.5 µg·mL−1 ) and MCF-7 cells (median inhibitory concentration (IC50 ) ∼ = 65.0 µg·mL−1 ), respectively. The analysis of matK gene displayed a good correlation with the main class of chemical compounds present in the EOs. However, the matK gene data did not show correlation with specific compounds. Keywords: Lauraceae; volatile compounds; terpenes; matK gene; phylogenetic analysis

1. Introduction The genus Ocotea is not a monophyletic group of the Lauraceae, which includes about 400 species occurring mostly in tropical and subtropical regions (Central and South America, the West Indies, and Africa) [1,2]. These species present alternate penninerved leaves; inflorescenses thyrsopaniculate to botryoid. Flowers are trimerous, bisexual, polygamous, or unisexual; tepals equal, rarely persistent on the rim; nine fertile stamens, the third whorl with glands; anthers with four loculos; receptacle very small and deeply tubular; in male flowers, rudimentary ovary to absent; fruit and cupule extremely variable in size and shape [1]. It is a very variable genus morphologically, being the largest genus in the Neotropics, with 170 species occurring in Brazil [3,4]. The economic importance of Ocotea species in the Amazon region has been related to numerous applications such as the use of their wood in lightweight construction and luxury furniture [5]. Int. J. Mol. Sci. 2017, 18, 1081; doi:10.3390/ijms18051081

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Phytochemical studies reported the occurrence of benzylisoquinoline alkaloids, neolignans, catechins from leaves and bark of O. porosa [6,7]; aporphine alkaloids from leaves of O. macrophylla; flavonols from O. vellosiana; and eudesmane sesquiterpenoids from O. corymbosa [8–10]. The volatile chemical profiles of Ocotea species are characterized by high concentrations of phenylpropanoids and terpenoids (hydrocarbons or oxygenated) [11,12]. Many studies have been reported on the biological activities of Ocotea metabolites: the alkaloid reticuline isolated from extract of O. duckei showed potent central nervous system depressant action [13]. (−)-Caaverine, a noraporphine alkaloid isolated from O. lancifolia, has shown high antiprotozoal activity against Leishmania and Trypanosoma cruzi parasites [14]. The chloroform fraction obtained from an extract of fruits of O. puberula and the alkaloid dicentrine displayed antinociceptive effects [15]. The butanolides isolated from roots of O. macrocarpa showed good cytotoxic activities against the A2780 ovarian cell line [16]. The flavonoids of O. notata showed antimycobacterial activity and ability to inhibit NO production by macrophages [17]. The essential oil of O. quixos, rich in trans-cinnamaldehyde and methyl cinnamate, showed anti-inflammatory properties in vitro and in vivo models [18]. Studies on the chemical characteristics of the species O. caudata, O. cujumary, and O. caniculata are rare and important because Ocotea species are classified as threatened to extinction by the Brazilian List and the risk of extinction is increased due the reduction of genetic variability [19,20] so knowledge of the genetic diversity is necessary for our understanding of the factors that determine essential oil quantity and quality in these economically important species [21]. 2. Results and Discussion 2.1. Essential Oil Chemical Composition The essential oil (EO) of Ocotea species provided different yields and the higher yields were found in the leaf EO for all samples (0.7–0.8%) (Table 1). Table 1. Collection data and essential oil yield of the samples of Ocotea occurring in Caxiuanã National Forest, Amazon, Brazil. Species

Geographic Coordinate

Voucher

Plant Material

Sample

Oil Yield (%)

O. caudata

18.800

S W 51.0◦ 27.00 27.400

MG 216263

Leaves Branches

Cau-L Cau-B

0.7 0.1

O. cujumary

S 01.0◦ 44.00 14.100 W 51.0◦ 27.00 20.400

MG 216269

Leaves Branches

Cuj-L Cuj-B

0.8 0.5

O. caniculata

S 01.0◦ 44.00 14.100 W 51.0◦ 27.00 20.400

MG 216262

Leaves Branches

Can-L Can-B

0.7 0.2

01.0◦

44.00

The most representative compounds class was sesquiterpene hydrocarbons (56.3–82.0%) in all samples from Caxianuã Forest (Figure 1). The O. caudata oils showed different chemical profiles in the tissues; in the EO from leaves (Cau-L) the monoterpene hydrocarbons (21.5%) were present, while in the branches (Cau-B) there was a high accumulation of oxygenated sesquiterpenoids (35.9%). The EO of O. cujumary leaves (Cuj-L) showed higher concentrations of oxygenated sesquiterpenoids (25.8%) than branches (Cuj-B, 4.0%), which showed significant amounts of monoterpene hydrocarbons (22.7%) and fatty acid derivatives (34.6%). The O. caniculata oils showed amounts of phenylpropanoids, especially in the branches (Can-B, 15.5%). Seventy volatile components were identified, comprising approximately 95.1% of the total composition of the oils (Table 2).

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Figure 1. Distribution of compound classes in essential oils (Eos) of Ocotea species. Monoterpene Figure 1. Distribution compound monoterpenoids classes in essential oils (Eos) of Ocotea hydrocarbons species. Monoterpene hydrocarbons (MH), of Oxygenated (OM), Sesquiterpene (SH), hydrocarbons (MH), Oxygenated monoterpenoids (OM), Sesquiterpene hydrocarbons (SH), Oxygenated Oxygenated sesquiterpenoids (OS), Diterpenes (DT), Phenylpropanoids (PP), Alkanes, aldehydes, sesquiterpenoids (OS), O. Diterpenes Phenylpropanoids (PP), Alkanes, aldehydes, and leaves ketones(Whi(AAK). and ketones (AAK). floribunda(DT), leaves (Flo-L), O. veraguensis leaves (Ver-L), O. whitei O.L); floribunda leaves (Flo-L), O. veraguensis leaves (Ver-L), O. whitei leaves (Whi-L); * Literature data * Literature data [22]. Cau-L (O. caudata leaves); Cau-B (O. caudata bark); Cuj-L (O. cujimary leaves);[22]. Cau-L leaves); bark); Cuj-L (O. cujimary leaves); Cuj-B (O. cujimary bark); Cuj-B(O. (O.caudata cujimary bark);Cau-B Can-L (O. (O. caudata caniculata leaves); Can-B (O. caniculata bark). Can-L (O. caniculata leaves); Can-B (O. caniculata bark).

The main compounds identified in O. caudata oils were bicyclogermacrene (29.6%), germacrene D (19.9%), β-caryophyllene (9.6%), α-pinene (9.8%),oils andwere β-pinene (9.7%) in the leaves (Cau-L) and δThe main compounds identified in O. caudata bicyclogermacrene (29.6%), germacrene cadinene (13.8%), germacrene D (8.9%), and α-muurulol (7.8%) in the branches (Cau-B). βD (19.9%), β-caryophyllene (9.6%), α-pinene (9.8%), and β-pinene (9.7%) in the leaves (Cau-L) Caryophyllene, germacrene-D, α-pinene, and β-pinene were the principal common constituents of and δ-cadinene (13.8%), germacrene D (8.9%), and α-muurulol (7.8%) in the branches (Cau-B). the EOs of leaves of Ocotea floribunda, O. holdridgeana, O. meziana, O. sinuata, O. tonduzii, O. valeriana, β-Caryophyllene, germacrene-D, α-pinene, and β-pinene were the principal common constituents of O. veraguensis, O. whitei, and two new undescribed Ocotea species [22]. the EOs of leaves of Ocotea floribunda, O. holdridgeana, O. meziana, O. sinuata, O. tonduzii, O. valeriana, In addition, these chemical compounds were identified in the leaves in other Lauraceae species. O. veraguensis, O. whitei, and two new undescribed Ocotea species [22]. The EO of leaves of Endlicheria arenosa was dominated by bicyclogermacrene (42.2%), germacrene D In addition, these chemical compounds were identified in the leaves in other Lauraceae species. (12.5%), and β-caryophyllene (10.1%) [23]. Similarly, the EO of Nectandra leucantha showed as the The EO of leaves of Endlicheria arenosa was dominated by bicyclogermacrene (42.2%), germacrene D main compounds bicyclogermacrene (28.4%), germacrene A (7.3%), α-pinene (6.6%), and β-pinene (12.5%), and β-caryophyllene [23].identified Similarly, the EO EOofofbranches Nectandra leucantha as the (4.6%) [24]. The sesquiterpene(10.1%) δ-cadinene in the was detectedshowed as the main main compounds bicyclogermacrene (28.4%), germacrene A (7.3%), α-pinene (6.6%), and β-pinene compound in EOs of leaf and bark of Beilschmiedia madang (17.0% and 20.5%, respectively) and was (4.6%) [24]. The in the EO of branches was detected as the main associated withsesquiterpene germacrene Dδ-cadinene in the oil of identified barks of Beilschmiedia glabra [25,26]. compound in EOs leaf andleaves bark of Beilschmiedia (17.0% and 20.5%, and was The EO of O.ofcujumary (Cuj-L) was richmadang in β-caryophyllene (22.2%)respectively) and caryophyllene associated with germacrene D in the oil of barks of Beilschmiedia glabra [25,26]. oxide (12.4%), followed by 2-tridecanone (7.3%) and δ-cadinene (6.6%). However, the EO of the The EO of O. cujumary leavesby (Cuj-L) was rich(30.0%), in β-caryophyllene (22.2%) caryophyllene branches (Cuj-B) was dominated 2-tridecanone limonene (20.5%), andand β-caryophyllene (8.1%). The occurrence fatty acid derivatives suchand as 2-tridecanone in Lauraceae speciesthe is not oxide (12.4%), followedofby 2-tridecanone (7.3%) δ-cadinene (6.6%). However, EOvery of the common. However, β-caryophyllene, caryophyllene oxide, and δ-cadinene were the main branches (Cuj-B) was dominated by 2-tridecanone (30.0%), limonene (20.5%), and β-caryophyllene compounds of the EOof oilfatty fromacid leaves of Cryptocarya [27]. in Lauraceae species is not very (8.1%). The occurrence derivatives such mandioccana as 2-tridecanone TheHowever, oils of O. caniculata showed caryophyllene predominance of sesquiterpenes of selinane andmain caryophyllane common. β-caryophyllene, oxide, and δ-cadinene were the compounds skeletons. In the leaves (Can-L), the main compounds were β-selinene (20.3%), β-caryophyllene of the EO oil from leaves of Cryptocarya mandioccana [27]. (18.9%), 7-epi-α-selinene (14.3%), andpredominance bicyclogermacrene (10.4%); in theofbranches selin-11The oils of O. caniculata showed of sesquiterpenes selinane(Can-B), and caryophyllane en-4-α-ol (20.6%), β-selinene (12.1%), 7-epi-α-selinene (9.0%), β-caryophyllene (7.1%), and the skeletons. In the leaves (Can-L), the main compounds were β-selinene (20.3%), β-caryophyllene phenylpropanoid (E)-asarone (8.8%) were identified. Interestingly, the leaf essential oil of O. foetens, (18.9%), 7-epi-α-selinene (14.3%), and bicyclogermacrene (10.4%); in the branches (Can-B), an endemic species of the Macronesian region (Canary Islands, Spain, and Madeira Islands, Portugal), selin-11-en-4-α-ol (20.6%), β-selinene (12.1%), 7-epi-α-selinene (9.0%), β-caryophyllene (7.1%), and the had very little concentration of monoterpenoids or sesquiterpenoids, but was rich in ethyl pphenylpropanoid (E)-asarone (8.8%) were identified. Interestingly, the leaf essential oil of O. foetens, coumarate [28]. an endemic species of the Macronesian region (Canary Islands, Spain, and Madeira Islands, Portugal), had very little concentration of monoterpenoids or sesquiterpenoids, but was rich in ethyl p-coumarate [28].

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Table 2. Chemical composition of essential oils of Ocotea species. RICalc , calculated retention index; RILit , literature retention index. Constituents E-2-Hexenal α-Thujene α-Pinene Camphene Sabinene β-Pinene Myrcene α-Phellandrene p-Cymene Limonene β-Phellandrene 1,8-Cineole γ-Terpinene α-Terpinolene α-Pinene oxide Linalool Borneol Terpinen-4-ol α-Terpineol Cuminal 2-Undecanol δ-Elemene α-Cubebene α-Ylangene α-Copaene β-Cubebene β-Bourbonene δ-Elemene Z-Caryophyllene β-Caryophyllene 2,5-Dimethoxy-p-cymene β-Copaene

RICalc

RILit

856 933 936 956 979 980 995 1009 1028 1030 1032 1033 1064 1089 1097 1104 1168 1178 1191 1238 1301 1340 1351 1373 1377 1392 1384 1392 1416 1421 1424 1428

854 931 932 953 976 974 991 1005 1026 1024 1031 1033 1062 1088 1095 1098 1165 1177 1189 1239 1301 1335 1345 1373 1374 1387 1387 1389 1408 1417 1424 1430

Cau-L

Cau-B

Cuj-L

Cuj-B

Can-L

Can-B

Flo-L *

9.8

2.1

22.5 1.7

9.7

1.8

2.2

21.3 0.7

2.1

1.8

20.5

2.7

Ver-L *

Whi-L *

1.1 0.2 0.7 0.1 0.1 0.3 1.1 1 19.8

0.8 12.7 0.3 7.3 0.5

1.1 4.0 1.3 0.1 0.1

0.1 1.7 0.1 0.2 0.2 0.1

2.0

2.2 2.0 0.8 1.0 1.6

2.0

4.6

0.8 5.1

2.2 0.1 0.1

1.5 9.6

1.2

2.5

0.7 0.4 0.3 22.2 0.4

8.1

1.3

0.1

0.8

1.1

0.8

0.3

0.1 0.7

0.1 0.3

18.9

7.1 0.9

2.5

2.3

15.2

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Table 2. Cont. Constituents β-Gurjunene α-trans-Bergamotene γ-Elemene α-Guaiene Aromadendrene Z-β-Farnesene Spirolepechinene α-Humulene Sesquisabinene Dehydroaromadendrane E-β-Farnesene allo-Aromadendrene trans-Cadina-1(6),4-diene γ-Selinene γ-Gurjunene γ-Muurolene Widdra-2,4(14)-diene Germacrene D β-Selinene Valencene cis-β-Guaiene trans-Muurola-4(14),5-diene 2-Tridecanone Viridiflorene Bicyclogermacrene α-Muurolene Germacrene A β-Bisabolene δ-Amorphene E,E-α-Farnesene γ-Cadinene 7-epi-α-Selinene

RICalc

RILit

1432 1436 1435 1439 1440 1443 1451 1455 1458 1460 1462 1463 1473 1477 1477 1476 1483 1484 1485 1493 1493 1491 1497 1493 1500 1499 1504 1509 1509 1510 1517 1517

1432 1432 1434 1439 1439 1440 1449 1452 1457 1460 1458 1461 1475 1470 1475 1478 1481 1484 1489 1491 1492 1493 1495 1496 1500 1500 1503 1505 1511 1508 1513 1520

Cau-L

Cau-B

Cuj-L

Cuj-B

Can-L

Can-B

Flo-L *

Ver-L *

Whi-L * 0.2 1.9 0.1

0.9 0.8 0.1

0.1 0.7 1.8

2.4

3.8

2.5

1.4 2.5

0.9 0.6 1.7 0.9

0.3

1.7

1.7

0.6 0.9 0.2 0.5 0.2 0.4 0.7

0.8 19.9

6.5 8.9

8.3

0.9 2.2 3.0 1.1 7.3

5.9

1.2 20.3

12.1

0.2 0.3 1.1

5.5

5.2 30.0 9.8 10.4

29.6 1.7

5.3 1.0

0.1 0.2

2

0.4

0.3 0.7

0.6 0.8

2.0

0.9

5.9 4.5

1.6

3.1 14.8

1.7 9.0

0.1

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Table 2. Cont. Constituents β-Cadinene cis-Calamenene δ-Cadinene trans-Cadina-1,4-diene α-Cadinene α-Calacorene Elemol Germacrene B E-Nerolidol β-Calacorene γ-Asarone Spathulenol Caryophyllene oxide Globulol Viridiflorol Carotol 6-Methoxyelemicin Guaiol Humulene epoxide II Z-Asarone 1,10-di-epi-Cubenol Junenol 1-epi-Cubenol Muurola-4,10(14)-dien-1β-ol epi-α-Cadinol allo-Aromadendrene epoxide Caryophylla-4(12),8(13)-dien-5β-ol α-Muurolol Cubenol

RICalc

RILit

1519 1523 1526 1532 1537 1542 1549 1558 1564 1564 1576 1579 1585 1592 1597 1586 1601 1597 1608 1625 1620 1620 1628 1628 1642 1632 1636 1642 1646

1518 1521 1522 1533 1538 1544 1549 1559 1561 1564 1572 1577 1582 1590 1592 1594 1595 1600 1608 1616 1618 1618 1627 1630 1638 1639 1639 1644 1645

Cau-L

1.4

Cau-B

13.8

Cuj-L

6.6 0.6

Cuj-B

4.7

Can-L

0.6

0.9 1.6

Can-B

3.9

Flo-L *

0.2

1.5

3.3

0.8 1.4

2.0

0.5 12.4

1.0 0.9

Whi-L *

0.7 0.6 0.4 0.2

0.6

0.4 2.5 0.5 6

8.5

2.0 0.9 1.2

2.7 6.3 1.2 1.0

4.0

5.2 1.7 3.4

3.0 3.8

1.4 0.6 0.4

3.3

2.0

0.5

3.3 1.4 3.2 7.8 2.2

0.9 1.5

3.7 0.2 0.1

0.2

0.7 0.4 1.4 1.0

Ver-L *

1.8

0.1 0.7 3.9

15.3

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Table 2. Cont. Constituents α-Cadinol Valerianol Selin-11-en-4α-ol 7-epi-α-Eudesmol Bulnesol 14-Hydroxy-(Z)-caryophyllene E-Asarone β-Sinensal E,E-Farnesylacetate Isohibaene Kaurene

RICalc

RILit

1652 1654 1657 1658 1662 1666 1683 1699 1843 1922 2034

1652 1656 1658 1662 1666 1666 1675 1699 1843 1923 2034

Cau-L

Cau-B

Cuj-L

Cuj-B

Can-L

2.2 6.8 3.1

Can-B

Flo-L *

Ver-L *

Whi-L *

1.8

1.5

1.8

20.6 4.2 29.5

2.3

1.5

0.9 3.6

2.1 8.8 0.6 10.1 0.7 34.0

RICalc = based on DB-5ms capillary column and alkane standards (C8-C32). RILit = based on Adams library. * Literature data (Takaku et al., 2007 [22]).

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ordertotodifferentiate differentiate between between the cluster analysis InInorder the analyzed analyzedOcotea Ocoteasamples, samples,a ahierarchical hierarchical cluster analysis usingthe thechemical chemicalconstituents constituents was was carried dendrogram is shown in Figure 2. 2. using carriedout outand andthe theresulting resulting dendrogram is shown in Figure According to these results, the samples were grouped in two main groups with similarity of 46.6%. According to these results, the samples were grouped in two main groups with similarity of 46.6%. GroupI Iisischaracterized characterized by by oils oils from from O. which present high Group O. caudata, caudata, O. O.whitei, whitei,and andO.O.floribunda, floribunda, which present high amounts of α-pinene (9.8–22.5%) and β-pinene (7.3–21.3%). A higher similarity (74.1%) was found amounts of α-pinene (9.8–22.5%) and β-pinene (7.3–21.3%). A higher similarity (74.1%) was found with with O. caudata and O. whitei due the proportions of α-pinene, β-pinene, and β-caryophyllene (see O. caudata and O. whitei due the proportions of α-pinene, β-pinene, and β-caryophyllene (see Table 2). Table 2). The main compound of O. floribunda oil was the diterpene kaurene (34.0%) and it decreased The main compound of O. floribunda oil was the diterpene kaurene (34.0%) and it decreased its its similarity level. Group II includes O. cujumary, O. caniculata, and O. veraguensis oils, the samples similarity level. Group II includes O. cujumary, O. caniculata, and O. veraguensis oils, the samples Cuj-L Cuj-L and Can-L present similar amounts of β-caryophyllene (22.2% and 18.9%, respectively). A and Can-L present similar amounts of β-caryophyllene (22.2% and 18.9%, respectively). A lower lower similarity was found in sample Ver-L, which was rich in bulnesol (29.0%) and p-cymene similarity (19.8%). was found in sample Ver-L, which was rich in bulnesol (29.0%) and p-cymene (19.8%).

Figure Linkageand andCorrelation CorrelationCoefficient Coefficient Distance. * Literature Figure2.2.Dendrogram Dendrogramwith with Complete Complete Linkage Distance. * Literature datadata (Takaku et al., 2007 [21]). (Takaku et al., 2007 [21]).

2.2.Antimicrobial Antimicrobialand andCytotoxic Cytotoxic Activities Activities 2.2. Allessential essential oils oils displayed displayed high antimicrobial inhibitory All antimicrobialactivity activityagainst againstE.E.coli coli(minimum (minimum inhibitory −1 ).−1Cau-L concentration(MIC) (MIC) < 19.5 µg·mL ). Cau-L Cuj-L showed notable activity against S. concentration < 19.5 µg·mL andand Cuj-L oils oils showed notable activity against S. epidermis epidermis and B. cereus (Table 3). It is not obvious what component(s) are responsible for the activity and B. cereus (Table 3). It is not obvious what component(s) are responsible for the activity against E. coli. against E. coli.oil Most essential oilshow components show only marginal activity this The organism. The Most essential components only marginal activity against this against organism. antibacterial antibacterial activities against the other bacteria are consistent with the activities of the essential oil activities against the other bacteria are consistent with the activities of the essential oil components components (Table 3).hand, On the hand,activity the cytotoxic activity against MCF-7 cells didvariation not display (Table 3). On the other theother cytotoxic against MCF-7 cells did not display in the variation in the median inhibitory concentration (IC50) values among all samples with an average of −1 median inhibitory concentration (IC50 ) values among all samples with an average of 63.0 µg·mL 63.0 µg·mL−1 (Table 3). The main compounds germacrene D, bicyclogermacrene, β-caryophyllene, α(Table 3). The main compounds germacrene D, bicyclogermacrene, β-caryophyllene, α-pinene, pinene, β-pinene, caryophyllene oxide, β-selinene, 7-epi-α-selinene have been reported as β-pinene, caryophyllene oxide, β-selinene, 7-epi-α-selinene have been reported as antimicrobial and antimicrobial and cytotoxic [29–33]. The observed cytotoxicities of some of the essential oil cytotoxic [29–33]. The observed cytotoxicities of some of the essential oil components are consistent components are consistent with the cytotoxicities of the essential oils themselves (Table 3). with the cytotoxicities of the essential oils themselves (Table 3). The EOs of leaves of Endlicheria arenosa, which are rich in bicyclogermacrene (42.2%), germacrene The EOsand of leaves of Endlicheria arenosa, whichthe aresame rich in (42.2%), germacrene D D (12.5%), β-caryophyllene (10.1%), showed ICbicyclogermacrene 50 value against Escherichia coli [23]. The (12.5%), and β-caryophyllene (10.1%), showed the same IC value against Escherichia coli7-[23]. 50 amounts of α-pinene EO from the leaves of Ruilopezia bracteosa (Asteraceae), with higher (24.3%), The EO from the(9.1%), leavesand of Ruilopezia bracteosa (Asteraceae), with activity higher amounts of α-pinene (24.3%), epi-α-selinene β-pinene (8.5%), showed antibacterial against Gram-positive and 7-epi-α-selinene (9.1%), and β-pinene (8.5%), showed antibacterial activity against Gram-positive and Gram-negative bacteria [34]. Gram-negative bacteria [34]. Terpenoids from plant oils prevent tumor cell proliferation through necrosis or induction of Terpenoids from plant oils cell proliferation through necrosis or induction apoptosis [35]. Germacrene D is prevent reported tumor as cytotoxic against cervical carcinoma (HeLa), leukemia of (HL-60), [35]. colonGermacrene carcinoma (HCT), breast adenocarcinoma (SKBr), and melanoma βapoptosis D is reported as cytotoxic against cervical carcinoma(A2058) (HeLa),[36]. leukemia Caryophyllene and caryophyllene oxide displayed activity against several tumor cells such as breast (HL-60), colon carcinoma (HCT), breast adenocarcinoma (SKBr), and melanoma (A2058) [36]. cancer (MCF-7), colon cancer (HCT-116), anddisplayed human prostate [37,38]. Thetumor valuescells of ICsuch 50 of as β-Caryophyllene and caryophyllene oxide activity(PC-3) against several breast cancer (MCF-7), colon cancer (HCT-116), and human prostate (PC-3) [37,38]. The values of IC50

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bicyclogermacrene, α-pinene, and β-pinene against MCF-7 cells were 19.0, 30.7, and 80.2 µg/mL, respectively [24,39]. of bicyclogermacrene, α-pinene, and β-pinene against MCF-7 cells were 19.0, 30.7, and 80.2 µg/mL, respectively Table 3. [24,39]. Antimicrobial and cytotoxic activities of Ocotea essential oils and some major essential oil components. MIC, minimum inhibitory concentration; IC50, median inhibitory concentration. Table 3. Antimicrobial and cytotoxic activities of Ocotea essential oils and some major essential oil −1) IC50 (μg·mL−1) MIC (μg·mL components. MIC, minimum inhibitory concentration; IC50 , median inhibitory concentration. Material

P. aer Can-L 1250.0 Material Cau-L 1250.0 P. aer Cuj-L 1250.0 Can-L 1250.0 α-Pinene 625 Cau-L 1250.0 Cuj-L 1250.0 β-Pinene 1250 α-Pinene 625 Limonene 1250 β-Pinene 1250 β-Caryophyllene 1250 Limonene 1250 β-Caryophyllene 1250 α-Humulene 1250 α-Humulene 1250 Germacrene D 1250 Germacrene D 1250 Caryophyllene oxide 1250 Caryophyllene oxide 1250 Gentamicin control 1.22 Gentamicin control 1.22 Tingenone control