Amit Chauhan - Academia.edu (original) (raw)

Papers by Amit Chauhan

Natural Product Communications, 2012

The essential oil composition of the leaves, stem, flowers and roots of Ligusticopsis wallichiana... more The essential oil composition of the leaves, stem, flowers and roots of Ligusticopsis wallichiana (DC.) Pimenov & Kljuykov were analyzed by GC-FID and GC-MS methods. Forty-five constituents, forming 93.2%–97.8% of the oil compositions, were dominated by acetylenic (31.5%–92.8%) compounds and sesquiterpenoids (0.3%–44.4%). The leaf essential oil was mainly composed 3,5-nonadiyne (35.8%), β-selinene (20.9%), α-funebrene (10.1%) and ( Z)-falcarinol (6.1%). The stem oil was dominated by acetylenic compounds (73.8%) represented by 3,5-nonadiyne (67.8%) and ( Z)-falcarinol (5.7%). On the contrary, the major components of the flower essential oil were sesquiterpenoids (37.5%), such as germacrene D (16.6%), α-funebrene (7.4%), and acetylenic compounds (31.5%), such as ( Z)-falcarinol (21.0%) and 3,5-nonadiyne (10.0%). Monoterpenoids constituted 23.9% of the flower oil with limonene (19.9%) as the single major constituent. The essential oil of the roots was dominated by 3,5-nonadiyne (90.5%)...

Chemistry & biodiversity, Jan 21, 2017

Fish-mint (Houttuynia cordata Thunb.), belongs to family Saururaceae has long been used as food a... more Fish-mint (Houttuynia cordata Thunb.), belongs to family Saururaceae has long been used as food and traditional herbal medicine. The present study was framed to assess the changes occurring in the essential-oil composition of Houttuynia cordata during annual growth and to evaluate allelopathic, antibacterial, antifungal and antiacetylcholinesterase activities. The essential-oil content ranged from 0.06-0.14% and 0.08-0.16% in aerial-parts and underground-stem, respectively. The essential oils were analysed by GC-FID, GC-MS and NMR ((1) H & (13) C). Major constituents of aerial-parts oil was 2-undecanone (19.4-56.3%), myrcene (2.6-44.3%), ethyl decanoate (0.0-10.6%), ethyl dodecanoate (1.1-8.6%), 2-tridecanone (0.5-8.3%) and n-decanal (1.1-6.9%). However, major constituents of underground-stem oil were 2-undecanone (29.5-42.3%), myrcene (14.4-20.8%), sabinene (6.0-11.1%), 2-tridecanone (1.8-10.5%), β-pinene (5.3-10.0%) and ethyl dodecanoate (0.8-7.3%). Cluster analysis revealed that ...

Industrial Crops and Products, 2016

In this study, successfully domesticated Himalayan thyme (Thymus linearis Benth.) to the subtropi... more In this study, successfully domesticated Himalayan thyme (Thymus linearis Benth.) to the subtropical region of north India was evaluated for essential oil yield and chemical composition at different crop durations and harvests. The essential oil content, dry herb yield and essential oil yield varied from 1.64-2.79%, 44.11-52.40 q ha −1 , and 85.57-108.71 l ha −1 , respectively. The resulting essential oil was analysed using GC-FID and GC-MS. Altogether, forty-four constituents, representing 98.0-99.7% of the total oil composition were identified. Major constituents of the oil were thymol (34.3-67.3%), p-cymene (4.0-27.4%), ␥-terpinene (4.9-24.4%), thymyl acetate (0.6-5.2%), ␤-bisabolene (0.8-5.1%), thymol methyl ether (2.4-3.7%), ␣-terpinene (0.7-3.6%), (E)-caryophyllene (0.7-2.9%), 3-octanone (0.6-2.3%), ␣-thujene (0.3-2.3%), borneol (0.5-1.8%), carvacrol (0.9-1.5%), and cis-sabinene hydrate (0.4-1.3%). The essential oil of Himalayan thyme produced in this region fulfilled the criterion set by European Pharmacopeia for common thymes.

The present study reports the variation in the essential oils (EOs) composition from needles and ... more The present study reports the variation in the essential oils (EOs) composition from needles and scale leaves of Pinus halepensis, Cupressus sempervirens and Juniperus phoenicea which collected from three different altitudes at Al-Jabel Al-Akhdar area, Libya. The impact of the altitude on the quantity and quality of EOs was studied. In addition, the antibacterial activity was evaluated using microdilution broth assay technique. The results showed that the highest percentages of the EOs yield were found in P. halepensis with 0.41, 0.60, and 0.43% for the altitudes of 125m (I), 391m (II), and 851m (III), respectively, while the lowest percentages of the yield were found in J. phoenicea, with 0.15, 0.07, and 0.18% at altitudes of I, II, and III, respectively. Based on P. halepensis EOs analyses using GC/MS, 35 components have been detected, which represents 89.92, 91.56, and 86.44% for the altitudes of I, II and III, respectively. Furthermore, high percentages from the components of α-pinene, β-pinene, α-terpineol and caryophyllene were identified at the three tested altitudes. For C. sempervirens EOs, 33 components were identified representing 84.94, 93.37 and 99.48% for levels I, II and III, respectively. The highest percentages of the EOs components in this species were α-pinene, terpinen-4ol and α-terpiny acetate at the three tested elevations. However, the detected main components in J. phoenecea EOs were α-pinene, α-myrcene, α-terpinyl acetate and γterpinene. The highest antibacterial activity was observed for the oils from P. halepensisat and J. phoenicea at altitude I against the Agrobacterium tumefaciens, Erwinia carotovora, Corynebacterium fascians and Pseudomonas solanacearum. While the EOs extracted from scale leaves of C. sempervirens obtained from trees growing at level II were the most active against the tested bacteria. The results of this work revealed the impacts of the environmental conditions on the EOs composition which affected significantly in its quantitative and qualitative performances. Consequently, their biological activities were varied considerably. Moreover, the obtained data offer the opportunity to choose EOs with preferential compound for pharmaceutical, pesticides, perfume and food industries in such important region in Libya.

A field study was conducted in the temperate climate (Western Himalayan region of Kumau) of India... more A field study was conducted in the temperate climate (Western Himalayan region of Kumau) of India to study the effects of different nitrogen and phosphorus levels (0, 50, 100, 150 kg ha -1 of nitrogen and 40, 60, 80 kg ha -1 of phosphorus) on growth, herb yield, spike yield, oil yield, essential oil quality, and output per unit of fertilizer on clary sage (Salvia sclarea L.). Efforts were made to elucidate the economics of N application through marginal analysis. Observations revealed that growth, and yield attributes increased with increasing levels of N and P fertilizers. The marginal profit earned per dollar invested on N fertilizer application varied with treatments, and at N100 kg ha -1 plus P60 kg ha –1 earned maximum profit $ 1.33. The quality of essential oil was not influenced by fertilizer application and acceptable in aroma industry. It is suggested that further research should be done under different environmental conditions.

Journal of Essential Oil Bearing Plants, 2012

ABSTRACT Coleus aromaticus Benth. collected from mid hill and foot hill regions of northern India... more ABSTRACT Coleus aromaticus Benth. collected from mid hill and foot hill regions of northern India was investigated for essential oil composition using gas chromatography (GC-FID) and gas chromatography- mass spectrometry (GC-MS). A total of forty-four constituents representing 85.9- 98.9 % of the oil composition were identified. Major components of these oils were thymol (57.7-66.4 %), γ-terpinene (5.8- 11.7 %), p-cymene (4.1-14.2 %), (E)-caryophyllene (2.6-3.6 %), caryophyllene oxide (1.3-1.5 %), and 1- octen-3-ol (1.0-1.8 %). The thymol content was higher in foot hills as compared to mid hills.

2014 Recent Advances in Engineering and Computational Sciences (RAECS), 2014

ABSTRACT

Tribology International, 2010

Thermohydrodynamic study for the analysis of elliptical journal bearings has been presented in th... more Thermohydrodynamic study for the analysis of elliptical journal bearings has been presented in the present work for three different grade oils commercially available. Finite difference method has been adopted for numerical solution of the Reynolds and Energy equation. ...

Tribology International, 2011

A comparative study based on the thermal performance of elliptical and offset-halves journal bear... more A comparative study based on the thermal performance of elliptical and offset-halves journal bearings has been carried out by solving energy equation while assuming Parabolic Temperature Profile Approximation across the fluid film for faster computation of temperatures. Investigation for the rise in oil film temperatures, thermal pressures, load capacity, and power loss for three commercially available grade oils have been

National Academy Science Letters, 2013

Variations in the essential oil composition of Laggera crispata (Vahl) Hepper & Wood due to plant... more Variations in the essential oil composition of Laggera crispata (Vahl) Hepper & Wood due to plant parts (leaf, flower, stem, and root) was assessed using gas chromatography (GC/FID) and gas chromatography-mass spectrometry. A total of 57 constituents, representing 86.39-93.55 % of the total oil compositions were identified. Major components of these essential oils were 2,5dimethoxy-p-cymene (22.28-75.55 %), 10-epic -eudesmol (0.51-21.93 %), linalool (0.03-9.84 %), caryophyllene oxide (0.35-7.97 %), a-humulene (1.40-6.20 %), eudesm-7(11)-en-4-ol (0.03-4.13 %), p-menth-3,8-diene (0.0-4.10 %), 7-epi-a-eudesmol (0.0-4.01 %), and (E)caryophyllene (1.06-3.88 %). Comparative results showed considerable variations in the quantitative and qualitative essential oil composition of L. crispata due to plant parts. Leaf essential oil was dominated by oxygenated sesquiterpenes (49.69 %), while the flower, stem, and root essential oils were characterised by higher amount of benzenoid compounds (49.81-64.41; 63.67 and 76.95 %, respectively). 2,5-dimethoxy-p-cymene, the most abundant constituent was noticed to be higher in root essential oil whilst it was recorded lowest in leaf essential oil. Moreover, the flower and stem essential oils were more closely related, while the leaf and root displayed more organ specific composition.

Natural Product Research, 2011

The leaf and root essential oil composition of Boenninghausenia albiflora Reichb and Meissner (fa... more The leaf and root essential oil composition of Boenninghausenia albiflora Reichb and Meissner (family: Rutaceae), collected from Uttarakhand, India, was analysed by capillary gas chromatography and gas chromatography-mass spectrometry. The major constituents identified in the leaf essential oil were β-myrcene, (Z)-β-guaiene, (Z)-β-ocimene and β-caryophyllene, whereas bicyclogermacrene, α-terpinyl acetate, geijerene and β-copaene-4α-ol were identified as the major constituents of the root essential oil. This is the first time that the chemical compositions of leaf and root essential oils of B. albiflora have been investigated in detail. The results show significant qualitative and quantitative variations in leaf and root oil composition.

Natural Product Research, 2013

Hydrodistilled essential oil of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;... more Hydrodistilled essential oil of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;Nutmeg Geranium&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; (Pelargonium × fragrans Willd.), grown in foothills of northern India was analysed by capillary gas chromatography (GC/flame ionisation detector (FID)) and GC-mass spectrometry (GC/MS). A total of 51 constituents, representing 90.2% of the total oil composition were identified. The oil was mainly dominated by monoterpenoids (58.4%), followed by sesquiterpenoids (19.4%), and phenyl propanoids (10.1%). Major constituents of the essential oil were fenchone (10.7%), methyl eugenol (9.9%), α-pinene (9.4%), α-thujene (7.6%), limonene (6.4%), spathulenol (4.7%), sabinene (4.3%), linalool (4.2%), (E)-caryophyllene (4.2%), terpinen-4-ol (3.2%), β-pinene (2.9%), caryophyllene oxide (2.2%) and bicyclogermacrene (2.1%). This is the first report on essential oil composition of Nutmeg Geranium oil grown in India.

Lubrication Science, 2011

This work presents theoretical and experimental investigations on offset-halves bearing to access... more This work presents theoretical and experimental investigations on offset-halves bearing to access the temperature rise at oilbush interface with three different grade commercial oils namely Mak 2T, Hydrol 68 and Mak Multigrade at different loads. The Reynolds equation ...

Journal of the Science of Food and Agriculture, 2014

BACKGROUND: Aegle marmelos (L.) Correa is a sacred medicinal and nutraceutical tree of India. The... more BACKGROUND: Aegle marmelos (L.) Correa is a sacred medicinal and nutraceutical tree of India. The present study planned to explore the chemotypic and seasonal variability of the leaf essential oil of A. marmelos from north India for proper industrial utilization. RESULTS: The essential oil yield varied from 0.37% to 0.80% in leaves of A. marmelos populations. Analysis of the essential oils by gas chromatography and gas chromatography-mass spectrometry, and the subsequent classification by statistical analysis showed three types of chemical compositions for A. marmelos with significant variations in their terpenoid compositions. Major components of the essential oils were limonene (31.0-90.3%), α-phellandrene (<0.05-43.5%), (E)-β-ocimene (0.7-7.9%), α-pinene (<0.05-7.5%), (E)-caryophyllene (0.5-5.3%), β-elemene (<0.05-4.2%) and germacrene B (0.0-3.3%). In addition to this, essential oil of a locally growing A. marmelos population was also investigated for seasonal variations. The essential oil yield in this population varied from 0.37% to 0.82% during different seasons. Major constituents, namely α-phellandrene (35.8-49.8%), limonene (24.7-34.3%), (E)-β-ocimene (4.2-10.0%) and α-pinene (6.0-8.0%), showed considerable variations due to season of collection. CONCLUSIONS: The growing location and harvesting season had a close relation to yield and quality of A. marmelos leaf essential oil. The results obtained are of significance for determining a suitable time for harvesting A. marmelos leaves.

Journal of Essential Oil Research, 2010

The essential oils obtained from Artemisia capillaris at different stages of flowering were analy... more The essential oils obtained from Artemisia capillaris at different stages of flowering were analyzed by GC and GC/MS. The main components of this oil were capillene, γ-terpinene, eugenol, limonene, p-cymene, myrcene and α-pinene. Capillene (40.1%), α-pinene (2.4%) and p-cymene (2.5%) were higher in the oil obtained from plants collected during full bloom stage, while γ-terpinene (24.6%) and eugenol (15.0%) were the main components of the oil from the seed setting stage. Characteristic of the oil was the presence of the rarely occurring compounds like capillene and norcapillene.

Industrial Crops and Products, 2013

Cymbopogon distans (Nees ex Steud.) Wats is a perennial aromatic grass growing wild in the temper... more Cymbopogon distans (Nees ex Steud.) Wats is a perennial aromatic grass growing wild in the temperate Himalayan region. In order to find new ecological areas for its commercial cultivation, an attempt has been made to introduce this plant to the subtropical region. In the present study, successfully domesticated lemon-scented strain of C. distans was evaluated for their essential-oil yield and chemical composition throughout the year. The essential-oil yields observed in the initial two years were 3.85 ± 0.22 mL/plant/year. The essential-oil content varied from 0.34 ± 0.05 to 0.44 ± 0.04% in different seasons. A total of thirty-eight constituents, representing 85.5-94.7% of the total oil compositions were identified using gas chromatography (GC) and GC-mass spectrometry (GC-MS) methods. Geraniol (10.7-20.8%), neral (15.0-18.0%), geranyl acetate (16.0-22.7%), geranial (19.7-24.7%), and limonene (1.9-6.1%) were identified as the major constituents of the essential-oil. Besides seasonal changes, variations in the essential-oil composition were also noticed between the first and second harvests of the plant.

Archives of Agronomy and Soil Science, 2009

The objective of this study was to determine the effect of intercropping of fodder crops on growt... more The objective of this study was to determine the effect of intercropping of fodder crops on growth and yield attributes of the essential oil-yielding multi-harvest aromatic plant geranium (Pelargonium graveolens L. Her. ex. Ait) under field conditions during 2005 2007. In addition ...