Phytochemical Constituents of Genus Nepeta

Arif Hussain Bhat; Aparna Alia; Bharty Kumar; Sofi Mubashir

Phytochemical Constituents of Genus Nepeta

Arif Hussain Bhat^1*, Aparna Alia¹, Bharty Kumar¹ and Sofi Mubashir²

¹Department of Botany, MVM Government College, Bhopal, Madhya Pradesh, India

²Department of Chemistry, University of Kashmir, Hazratbal Srinagar, Jammu and Kashmir, India

*Corresponding Author:: Arif Hussain Bhat
Department of Botany
MVM Government College, Bhopal, Madhya Pradesh
India
Tel: +02551 220 099
Email: arifbhat96@gmail.com

Received date: 26/05/2018; Accepted date: 20/06/2018; Published date: 25/06/2018

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Abstract

Genus Nepeta (family Lamiaceae) is native to Europe, Asia, and Africa and they are commonly known as catmints. The essential oils of Nepeta genus are characterized by the presence of one or more of the nepetalactone isomers which are the biochemical markers of this genus. The major compounds present in the essential oils of different Nepeta species have been summarized in this review article.

Keywords

Nepeta, Phytochemical Constituents, Aromatic Constituents.

Introduction

Lamiaceae - the ‘mint family’-is cosmopolitan with Mediterranean as the chief centre of distribution. The family comprises a total of 180 genera and 3500 species. Harley et al. recognize 236 genera and 7200 species [1], and Heywood et al. assign 6900 species [2]. In India, the family is represented by 67 genera and 405 species distributed mainly in mountainous regions. The members of the family are characterized by the quadriangular stem, verticillaster inflorescence, bilipped flowers, gynobasic style, deeply 4-lobed ovary and aromatic nature. Kashmir Himalaya is located in the northwestern extreme of the Himalayan biodiversity hotspot and contributes nearly 20% species within just 2.15% of the total land area of entire Himalaya [3]. This region is a hub of medicinal and aromatic plants, most of which flourish in the sub-alpine/alpine mountainous region. Lamiaceae is widely used in traditional systems of medicine and horticulture. The genus is native to Europe, Asia, and Africa and they are commonly known as catmints. The essential oils of Nepeta genus are characterized by the presence of one or more of the nepetalactone isomers which are the biochemical markers of this genus. Several species of the genus Nepeta have interesting biological activities and are used in traditional system of medicine as laxative to treat dysentery, kidney and liver diseases and teeth troubles ;they are also used as diuretic, diaphoretic, vulnerary, antispasmodic, anti-asthmatic, tonic, febrifuge and sedative agents [4-7]. Several Nepeta species are also reported to reduce serum lipids and anti-inflammatory effects [8,9]. Most Nepeta species are rich in essential oils and various biologically active iridoids/monoterpene nepetalactones have been reported in several Nepeta species possessing diverse biological activities, viz., feline attractant, canine attractant, insect repellant and arthropod defense [10,11]. Some specific reports on medicinal properties of Labiates include antitumor and antiinflammatory activity [12], antioxidant activity [13], anticancer activity [14] and antibacterial activity [15]. In Kashmir Himalaya, Lamiaceae is the second largest gamopetalous family with 32 genera and 88 species.

The Key compounds [16] i.e., one or more of the nepetalactone isomers which are the biochemical markers of this genus, some major compounds present in the essential oils of few species and some major compounds present in few common Himalayan species are summarized in the tables (Tables 1-3) below:

Sr No	Species	Principal Compounds	Ref
1	N. sintenissii	4aβ,7α,7aα-nepetalactone; 1, 8-cineole; β-elemene/ β-elemol; (Z)-β-farnesene/farnesol; germacrene-D; α-terpineol/4-Terpineol; 4aα,7α,7aα-nepetalactone,	[17]
2	N. racemosa	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone; 4aα,7α,7aα-nepetalactone,	[18]
3	N. assurgens	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 1, 8-cineole; α-pinene/ β-pinene; O: α-terpineol/4-Terpineol; 4aα,7α,7aα-nepetalactone	[19]
4	N. cadmea	4aα,7α,7aα-nepetalactone; 4aα,7α,7aα-nepetalactone,	[20]
5	N. caesarea	4aα,7α,7aα-nepetalactone	[21,22]
6	N. cephalotes	4aα,7α,7aα-nepetalactone; 1, 8-cineole; α-pinene/ β-pinene; 4aα,7α,7aα-nepetalactone,	[23,24]
7	N. crassifolia	4aα,7α,7aα-nepetalactone; 4aα,7α,7aα-nepetalactone,	[25]
8	N. x faassenii	4aα,7α,7aα-nepetalactone; 4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone; 1, 8-cineole; germacrene-D; α-pinene/ β-pinene; 4aα,7α,7aα-nepetalactone,	[26]
9	N. govaniana	4aα,7α,7aα-nepetalactone; β-elemene/ β-elemol; germacrene-D;	[27]
10	N. mirzayanni	4aα,7α,7aα-nepetalactone; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide; 4aα,7α,7aα-nepetalactone,	[24]
11	N. persica	4aα,7α,7aα-nepetalactone; 4aα,7α,7aα-nepetalactone,	[28]
12	N. racemosa	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone;	[29]
13	N. teydea	4aα,7α,7aα-nepetalactone; α-pinene/ β-pinene; α-terpineol/4-Terpineol;	[30]
14	N. argolica ssp	4aα,7α,7aβ-nepetalactone; 4aα,7α,7aα-nepetalactone,	[31]
15	N. atlantica	4aα,7α,7aβ-nepetalactone; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide; (Z)-β-farnesene/farnesol; 4aα,7α,7aα-nepetalactone,	[32]
16	N. cataria	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone; 1, 8-cineole; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide; limonene/ linalool; 4aα,7α,7aα-nepetalactone,	[32-34]
17	N. coerulea	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone; 4aβ,7α,7aβ-nepetalactone;	[35]
18	N. granatensis	4aα,7α,7aβ-nepetalactone; 1, 8-cineole; α-pinene/ β-pinene; 4aα,7α,7aα-nepetalactone,	[32]
19	N. meyeri	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aα,7α,7aα-nepetalactone,	[36]
20	N. nuda	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 1, 8-cineole; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide;	[37,38]
21	N. nepetella	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone;	[35]
22	N. racemosa	4aα,7α,7aβ-nepetalactone;	[39]
23	N. rtanjensis	4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone; germacrene-D; α-pinene/ β-pinene; 4aα,7α,7aα-nepetalactone,	[40,41]
24	N. septemcrenata	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 1, 8-cineole; β-elemene/ β-elemol; limonene/ linalool; α-terpineol/4-Terpineol; 4aα,7α,7aα-nepetalactone,	[42]
25	N. transcaucasica	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; germacrene-D; 4aα,7α,7aα-nepetalactone,	[43]
26	N. tuberose	4aα,7α,7aβ-nepetalactone; 1, 8-cineole; 4aα,7α,7aα-nepetalactone,	[32]
27	N. bornmuelleri	4aβ,7α,7aα-nepetalactone; 1, 8-cineole; 4aα,7α,7aα-nepetalactone,	[24]
28	N. eremophila	4aβ,7α,7aα-nepetalactone; 1, 8-cineole; 4aα,7α,7aα-nepetalactone,	[44]
29	N. persica	4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone; α-pinene/ β-pinene;	[45]
30	N. saccharata	4aβ,7α,7aα-nepetalactone; germacrene-D; 4aα,7α,7aα-nepetalactone,	[46]
31	N. argolica	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone; 4aβ,7α,7aβ-nepetalactone;	[47]
32	N. grandiflora	4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aβ-nepetalactone;	[48]
33	N. kotschyi	4aβ,7α,7aβ-nepetalactone; 1, 8-cineole; 4aα,7α,7aα-nepetalactone,	[49]
34	N. crassifolia	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aβ,7α,7aα-nepetalactone; 4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone; 1, 8-cineole;	[50]
35	N. betonicifolia	4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone; 1, 8-cineole; germacrene-D; 4aα,7α,7aα-nepetalactone,	[46]
36	N. crassifolia	4aα,7α,7aα-nepetalactone; 4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone;	[34]
37	N. nuda	4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone; β-elemene/ β-elemol; germacrene-D;	[51]
38	N. angustifaliathe	nepetalactone/ epinepetalactone; 4aα,7α,7aα-nepetalactone,	[52]
39	N. cataria	nepetalactone/ epinepetalactone; 1, 8-cineole; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide; β-elemene/ β-elemol; (Z)-β-farnesene/farnesol; germacrene-D; limonene/ linalool; α-pinene/ β-pinene; α-terpineol/4-Terpineol; 4aα,7α,7aα-nepetalactone,	[53,59]
40	N. mahanensis	nepetalactone/ epinepetalactone; 1, 8-cineole; germacrene-D; 4aα,7α,7aα-nepetalactone,	[44]
41	N. nepetella	nepetalactone/ epinepetalactone;	[54]
42	N. tuberosa	5,9-dehydronepetalacone/(7R)-trans,trans-nepetalactone; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide;	[55]
43	N. cataria	5,9-dehydronepetalacone/(7R)-trans,trans-nepetalactone; 4aα,7α,7aα-nepetalactone,	[56]
44	N. ellptica	5,9-dehydronepetalacone/(7R)-trans,trans-nepetalactone;	[57]
45	N. parnassica	4aα,7α,7aα-nepetalactone; 4aα,7α,7aβ-nepetalactone; 4aα,7β,7aβ-nepetalactone/4aα,7β,7aα-nepetalactone; 1, 8-cineole; (E or Z) α or β-caryophyllene/ β-caryophyllene oxide; α-pinene/ β-pinene; α-terpineol/4-Terpineol; 4aα,7α,7aα-nepetalactone,	[58]
46	N. mussini	nepetalactone/ epinepetalactone;	[59]

Table 1. Species which contained nepetalactone as principal constituents.

Species Name	Major compounds with percentage
N. atlantica	4aa,7a,7a-nepeta1actone (71.4%)	dihydronepetalactone (45) (3.1%)	3-caryophyllene (8.2%)	farnesol (48) (2.5%)	a-curcumene (50) (1.3%)
N. cataria	4aa,7a,7a-nepeta1actone (77.4%)	dihydronepetalactone (5.0%)	terpinene (46) (4.2%)	limonene (4.1%)	Thymol (1.3%)
N. granatensis	4aa,7a,7a-nepeta1actone (39.4%)	eucalyptol (1 ,8-cineole) (24.0%)	a-pinene (6.3%)	a-phellandrene (49) (5.8%)	p-cymene (51) (3.8%)
N. tuberose	4aa,7a,7a-nepeta1actone (76.8%)	dihydronepetalactone (5.9%)	menthol (47) (1.6%)	a-pinene (1.3%)	eucalyptol (1 ,8-cineole)(1 .2%)

Table 2. Major compounds present in the essential oils of few Nepeta species.

Species Name	Major compounds with percentage
N. clarkei	a-guaiene (82) (10.0%); germacrene D (13.0%); fl-sesquiphellandrene (22.0%) indodial -monoenol acetate diastereomers (25.3%)
N. discolor	p-cymene (9.8%); fl-caryophyllene (18.6%); 1,8-cineole (25.5%)
N. elliptica	(7R)-trans, trans-nepetalactone (83.4%)
N. erecta	isoiridomyrmecin (66.7%)
N. govaniana	pregeijerene (20.7%); isoiridomyrmecin (35.2%)
N. leucophylla	iridodial dienol diacetate (83) (7.8%); dihydroiridodial diacetate (84) (18.2%) indodial J-monoenol acetate (25.4%)

Table 3. Major compounds present in some common Himalayan Nepeta species.

Conclusion

The composition of the essential oil has been varying according the region, soil type and environmental condition from where the plant species have been collected [60,61]. It has been found from the literature that the most of species growing in the Himalayas region have compounds other than nepetalactone as major constituents in their essential oils as compare to the species growing in other part of the world (Iran, Tehran, Serbia, Egypt, Turkey, Brazil, USA etc.), which have both nepetalactone along with its derivatives and other than nepetalactone compounds as the major ingredient of their essential oils. The essential oil isolated from different plant parts viz. stem, leaves, flowers (fresh or dry) collected at different age and vegetative cycle stage have no major effect on the composition of the oil. It has been also found from the literature that the oil of different species of Nepeta have been mostly isolated from aerial parts mainly collected during full flowering stage with hydro distillation using Clevenger type apparatus gives good results. For the sustainable growth and development, a gradual shift from the use of synthetic drugs and agrochemicals to the natural ones have been witnessed as the latter have proven to be non-toxic, cheap and easily available. Active ingredients isolated from genus Nepeta has been reported to show wide array of biological activity in medicinal and agriculture field. Depending upon the multiple uses of secondary metabolites obtained from genus Nepeta, their structure-activity relationship and activity screening goes unabated. The present review would be supportive in the enhancement of today’s research in the development of new biologically potent compounds derived from plants which would find many applications in medicinal and agricultural fields.

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