INTRODUCTION:

Uttarakhand is a part of the North-Western Himalayas and is located between 28°43'-31°27'N latitudes and 77^o34'–81^o02' E longitudes. The river Tons separates the state from Himachal Pradesh in the north-west, whereas the river Kali separates it from Nepal in the east. The greater Himalaya is the northern boundary of the state and is also the international border with China (Tibet). India in general and Himalayan region in particular is known for its biological richness and has always been a botanist’s paradise. Uttarakhand state encompasses an area of 53,485sq.Km., which accounts for nearly 15.5 percent of the total geographical area of Western Himalayas. Most of the northern parts of the state are covered by the high Himalayan ranges and glaciers, while the lower reaches are densely forested.

Presently, 95% raw materials required by pharmaceuticals and drug manufactures are collected from the wild and remote areas [1]. The climatic variations from subtropical to alpine have favored the growth of many aromatic plants. The genus Artemisia (family: Asteraceae) is a source of valuable drugs and essential oils because of its intricate chemical composition comprising several chemotypes. In our previous reports on chemical composition of various Artemisia species from different origins show the presence of phenyl alkynes (61.2%, 85.5%), viz. capillene 60.2% and 82.9% from aerial part and besides 1-phenyl-penta-2,4-diyne. Besides phenyl alkynes the leaf oil contained γ-terpinene (11.1%), p-cymene (4.5%), and (E)-ß-ocimene (4.4%), as major compounds from root reported Artemisia capillaris Thunb. syn. A. scoparia Waldst. and Kit. (family: Asteraceae) [2]. Chemical profile of the hydro distilled essential oil obtained from the aerial parts of Artemisia japonica Thunb. (Syn. Artemisia parviflora Buch-Ham. ex D. Don) from Kumaun Himalaya was dominated by linalool (27.5%), germacrene D (11.2%), (E)-ß-ocimene (6.5%), 1, 8-cineole (5.5%), (Z)-ß-ocimene (5.5%) [3]. Present communication author presenting chemical composition of aerial part of Artemisia nilagirica Clarke collected from Milam glacier.

MATERIAL AND METHODS:

Plant collection, identification and isolation of essential oils:

The fresh leaves of Artemisia nilagirica Clarke. were collected from Milam glacier (latitude 30.48° N, longitude 80.10° E and an altitude of 3400m) in 2008 from Uttrakhand, India. The plant material was authenticated from Botanical Survey of India, Dehradun. The voucher specimen (Phyto/Chem/05) has been deposited in the Phytochemistry laboratory of the Chemistry Department, Kumaun University, Nainital. Fresh leaves (1.5kg) were subjected to steam distillation using a copper electric still, fitted with spiral glass condensers for four hours. The distillates were saturated with NaCl and extracted with n-hexane and dichloromethane. The organic phase was dried over anhydrous sodium sulfate and the solvents were distilled off in a rotary vacuum evaporator at 30°C and the percentage oil content was calculated on the basis of fresh weight of plant materials. The crude oil was kept in a cool and dark place until further analyses.

GC and GC-MS analysis:

The oils were analyzed by using a Nucon 5765 gas chromatograph (Rtx-5 column, 30m ×0.32mm, FID), split ratio 1: 48, N2 flow of 4kg/cm2and on Thermo Quest Trace GC 2000 interfaced with MAT Polaris Q Ion Trap Mass spectrometer fitted with a Rtx-5 (Restek Corp.) fused silica capillary column (30m × 0.25mm; 0.25µm film coating). The column temperature was programmed 60 – 210°C at 3°C/min using He as carrier gas at 1.0mL/min. The injector temperature was 210°C, injection size 0.1µL prepared in hexane, split ratio 1:40. MS were taken at 70 eV with a mass range of 40 - 450 amu.

Identification of the components:

Identification of constituents were done on the basis of Retention Index (RI, determined with reference to homologous series of n-alkanes (C9-C₂₄), Polyscience Corp., Niles IL) under identical experimental condition), co injection with standards (Sigma and known essential oil constituents (standard isolates), MS Library search (NIST and WILEY), by comparing with the MS literature data [4]. The relative amounts of individual components were calculated based on GC peak area (FID response) without using correction factor.

RESULT AND DISCUSSION:

Chemical composition of essential oils of aerial parts of Artemisia nilagirica were analyzed and compared by using capillary GC and GC-MS. Essential oil yield was 0.90% (v/w). The GC and GC/MS analysis led to the identification of twenty constituents forming 86.3% of the total oil compositions. The identified constituents with their relative content and class composition are given in Table 1.

Table 1: Chemical composition of essential oil of aerial parts of Artemisia nilagirica Clarke from Uttrakhand, India

Sr. No	RI _Exp.	RI _Lit.	Name of Compound	Percentage	*Identification
1.	935	932	alpha-Pinene	1.2	RI, MS
2.	971	969	Sabinene	1.5	RI, MS
3.	997	1001	(3E) Hexenyl acetate	0.6	RI, MS
4.	1001	1004	(3Z)-Hexenyl acetate	0.8	RI, MS
5.	1018	1020	p-Cymene	0.5	RI, MS
6.	1025	1026	1,8-Cineole	1.2	RI, MS
7.	1054	1056	Artemisia ketone	55.07	RI, MS
8.	1100	1102	Perillene	3.2	RI, MS
9.	1127	1128	(Z) Epoxy ocimene	1.2	RI, MS
10.	1134	1137	€ Epoxy ocimene	0.6	RI, MS
11.	1167	1165	Borneol	0.7	RI, MS
12.	1238	1239	Carvone	1.4	RI, MS
13.	1408	1407	Longifolene	0.9	RI, MS
14.	1424	1417	ß-Caryophyllene	6.5	RI, MS
15.	1436	1448	(Z)- ß-Farnesene	0.7	RI, MS
16.	1459	1455	€-ß-Farnesene	0.4	RI, MS
17.	1484	1484	Germacrene D	5.8	RI, MS
18.	1492	1492	(Z)-ß-Guaine	0.4	RI, MS
19.	1493	1501	ß-Himachallene	0.3	RI, MS
20.	1497	1503	€-ß-Guaine	0.3	RI, MS
21.	1518	1513	γ-Cadinene	0.2	RI, MS
22.	1676	1684	Germacra-4,5,10-trien-1-a-ol	2.1	RI, MS
Total				86.3

Chemical constituents of essential oil composition of aerial parts of Artemisia nilagirica was dominated by artemisia ketone (55.07%), ß-caryophyllene (6.5%), germacrene D (5.8%), perillene (3.2%). It has been noted that artemisia ketone is present in high percentage in it with some other compounds. In previous report from other studies showed that essential oils composition of the aerial parts of Artemisia nilagirica (Clarke) Pamp. var. septentrionalis Pamp. in different seasons viz. spring, summer, rainy, autumn and winter seasons under foot hills agroclimatic conditions, the major constituents identified were artemisia ketone (38.3%-61.2%), chrysanthenone (1.5%-7.7%), germacrene D (3.1%-6.8%), ß-caryophyllene (1.9%-6.8%), germacra-4,5,10-trien-1-a-ol (1.9%-4.9%) and artemisia alcohol (1.4%-3.6%) were present [5]. Another report showed that the plant collected from Kagguchi village Western Ghats, contains major components in A. nilagirica essential oil, α-thujone (34.24%) is the major compound followed by γ- curcimene (11.40%), α- caryophyllene (9.97%), lavundulol (4.03%) and germacrene (3.81%) [6]. Essential oil of A. nilagirica from northern hilly areas of India which contained forty three compounds, out of which, α-thujone (36.35%) is the major compound followed by β-thujone (9.37%), germacrene (6.32%), 4-terpineol (6.31%), camphene (5.47%), β-caryophyllene (5.43%) and borneol (4.12%) to those obtained by Sati et al. [7]. In comparison to previous studies very few components to some extent were present, but there percentage is varying in this report. This shows that the essential oil composition of aromatic plants vary with altitude and temperature variation.

CONCLUSIONS:

The genus Artemisia (Family: Asteraceae) is a source of valuable drugs and essential oils because of its intricate chemical composition comprising several chemotypes. The reported compounds showed very good antimicrobial, antioxidant and other biological activities. Thus, the essential oil of Artemisia nilagirica also will help in cosmetic industry to develop new drugs and products and its production by cultivation in large will become a source of employments in Uttrakhnad also.

ACKNOWLEDGMENTS:

The author is grateful to the Head, Department of Chemistry, Kumaun University, Nainital for GC-MS analysis. Also thankful to BSI, Dehradun for the identification of the plant.

REFERNCES:

1. Kehimkar I (2000). In: Common Indian Wild Flowers. Bombay Natural Historical Society. Oxford University Press.

2. Joshi RK, Padalia RC, Mathela CS (2010). Phenyl alkynes rich essential oil of Artemisia capillaris Natural Product Communication 5: 816-817.

3. ^{Joshi RK (2015). Volatile oils composition of
Artemisia japonica Thunb.
from} ^{Western
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96-97.}

4. Adams RP (2007). Identification of essential oil components by gas chromatography/mass spectroscopy, Allured Publishing Corporation, Carol Stream, IL, USA.

5. Padalia RC, Verma RS, Chauhan A, Chanotiya CS (2014). Seasonal Variation in Essential oil Composition of Artemisia nilagirica var. septentrionalis from Foot Hills of Western Himalaya. Rec. Nat. Prod 8 (3): 281-285.

6. Kishmu Lingan (2018). Antifungal Activity of Artemisia Nilagirica Essential Oil from the Western Ghats Nilgiris against Food Borne Fungi. J Appl Microbiol Biochem. Vol.2 No.2:6.

7. Sati SC, Sati N, Ahluwalia V, Walia S, Sati OP (2013) Chemical composition and antifungal activity of Artemisa nilagirica essential oil growing in northern hilly areas of India. Nat Prod Res 27: 45-48.

Received on 15.05.2020 Modified on 09.06.2020

Asian J. Pharm. Ana. 2020; 10(4):182-184.

DOI: 10.5958/2231-5675.2020.00033.2