Chemical Composition of Ambrosia trifida Essential Oil and Phytotoxic Effect on Other Plants

This study aimed to identify the main components of an essential oil produced from leaves of Ambrosia trifida and to evaluate its potential allelopathic effect on seed germination and seedling growth of lettuce, watermelon, cucumber and tomato. The essential oil was obtained by hydrodistillation and characterized chemically by gas chromatography (GC) coupled with both mass spectrometry (MS) and flame ionization detector (FID). Total 69 compounds were identified, with limonene (20.7 %), bornyl acetate (15.0 %), borneol (14.7 %) and germacrene D (11.6 %) as the major components. The working solutions of the essential oil emulsified with Tween 20 and dissolved in distilled water were prepared at four concentration levels (0.01, 0.1, 0.5 % and 1 %, v/v). The results obtained showed that increase in essential oil concentration leads to decrease in seed germination, as well as shoot and radical length of lettuce, watermelon, cucumber and tomato. The obtained data revealed a highly significant effect (p lt 0.05) between control and 1 % and 0.5 % oil concentrations in all treatments. The essential oil of A. trifida exhibited more powerful phytotoxic effects on lettuce, watermelon and tomato than on cucumber regarding germination and early seedling growth.This is the peer-reviewed version of the article: Sarić-Krsmanović Marija, Gajić-Umiljendić Jelena, Radivojević Ljiljana, Rajković Miloš, Santrić Ljiljana, Đurović-Pejčev Rada, "Chemical Composition of Ambrosia trifida Essential Oil and Phytotoxic Effect on Other Plants" 17, no. 1 (2020):e1900508, [https://doi.org/10.1002/cbdv.201900508]

Phytochemical Diversity in Essential Oil of Vitex negundo L. Populations from India

Vitex negundo L., commonly known as the ‘Nirgundi’ has a long history of medicinal use in traditional and folk medicines for various diseases. To explore the diversity of the essential oil yield and composition of V. negundo, 23 populations were collected during spring season from the western Himalayan region. The essential oil yields varied from 0.06 to 0.10% in different populations of V. negundo. GC-FID, GC-MS, and statistical analysis of the leaf volatile oils showed significant phytochemical diversity. The volatiles of V. negundo were complex mixtures of 61 constituents, with sabinene (2.8-40.8%), viridiflorol (10.7%-23.8%), β-caryophyllene (5.3-21.4%), terpinen-4-ol (0.1-7.2%), epi-laurenene (2.2-5.9%), humulene epoxide II (0.5-4.6%), and abietadiene (0.1%-4.3%) as major constituents. Based on the distribution of major constituents, four groups were noticed by the multidimensional scaling and hierarchical average linkage cluster analyses. In conclusion, the yield and composition of the essential oils isolated from V. negundo varied considerably, depending on the origin

A New Source of Elemol Rich Essential Oil and Existence of Multicellular Oil Glands in Leaves of the Dioscorea

Dioscorea species is a very important food and drug plant. The tubers of the plant are extensively used in food and drug purposes owing to the presence of steroidal constituent’s diosgenin in the tubers. In the present study, we report for the first time that the leaves of Dioscorea composita and Dioscorea floribunda grown under the field conditions exhibited the presence of multicellular oil glands on the epidermal layers of the plants using stereomicroscopy (SM) and scanning electron microscopy (SEM). Essential oil was also isolated from the otherwise not useful herbage of the plant, and gas chromatographic-mass spectroscopy analysis revealed confirmation of the essential oil constituents. Out of the 76 compounds detected in D. floribunda and 37 from D. composita essential oil, major terpenoids which are detected and reported for Dioscorea leaf essential oil are α-terpinene, nerolidol, citronellyl acetate, farnesol, elemol, α-farnesene, valerenyl acetate, and so forth. Elemol was detected as the major constituent of both the Dioscorea species occupying 41% and 22% of D. Floribunda and D. composita essential oils, respectively. In this paper, we report for the first time Dioscorea as a possible novel bioresource for the essential oil besides its well-known importance for yielding diosgenin

Composition of a new chemotype of <i style="">Tanacetum nubigenum</i>

1922-1926(3R,6R)-Tetrahydro-6-ethenyl-2,2,6-trimethyl-4H-pyran-3-acetate [3R,6R)-linalool oxide acetate] 1 (69.37%) along with 2-hydroxy-4,6-dimethoxyacetophenone 2, (E)- and  (Z)-2-(2,4-hexadiynylidene)-1,6-dioxaspiro[4,4]non-3-ene 3 and 4, ß-eudesmol 5 and selin-11-en-4-ol 6 have been isolated from Tanacetum nubigenum Wall of Kumaon region of North Western Himalaya at an altitude of 3600-4300 m.  (3R,6R)-linalool oxide acetate 1 has not been reported in Tanacetum species or from any other natural source. Presence of compounds 1-6 and absence of previously reported chrysanthenol and related esters makes it a new chemotype within the genus Tanacetum

Chemical composition of Inula cuspidata C.B. Clarke

1249-1253Thymyl isobutyrate, thymol, thymyl isovalerate, 8α-hydroxy presilphiperfolene and intermedeol have been isolated from steam volatile extract of Inula cuspidata and identified from their spectral data, synthesis and chemical modification of major constituents. Sharp qualitative and quantitative variations among the constituents of leaf, flower and roots of Inula cuspidata are noticed

<span style="mso-bidi-language:HI">Chemical perspective of <i>Tagar‒</i>An<i> </i>Ayurvedic drug </span>

474-477Valeriana wallichii DC., commonly known as Tagar is an important ingredient of Ayurvedic recipes for the treatment of nervous unrest and emotional problems. Besides, roots provide commercially important essential oil used in perfumery. Morphologically it is a single species and is common in the Himalayan region (1220-2134 m) with no subspecies or varieties. The investigations, however, revealed the existence of chemically different forms (chemical races) within V. wallichii DC on the basis of chemical analysis of root extracts (essential oils and valepotriates) responsible for the activity. Chemotype-I is represented by maaliol (64.3%) while the type-II possesses patchouli alcohol (40.2%) in their essential oils. Interestingly, Charak and Sushruta Samhita have also documented the existence of two types of Tagar known as Pindtagar and Nata having medicinal properties. </span

Chemical investigation of the essential oil of Laggera crispata (Vahl) Hepper & Wood from India, Short communication

Hydrodistilled essential oil of the aerial parts of Laggera crispata (Vahl) Hepper & Wood, collected from the Kumaon region of the western Himalayas was analysed by gas chromatography and gas chromatography–mass spectrometry. Eighty constituents, accounting for 83.9 % of the total oil composition, were identified. The oil was mainly dominated by sesquiterpenoids (45.3 %) and benzenoid compounds (33.9 %). Among them, 2,5-dimethoxy-p-cymene (32.2 %), 10-epi-γ-eudesmol (14.7 %), β-caryophyllene (6.9 %) and caryophyllene oxide (5.4 %) were major components of the oil