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82 result(s) for "Terpinyl acetate"
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A comparative study of essential oil components of selected promising small cardamom (Elettaria cardamomum (L.) Maton) landraces in Cardamom Hill Reserve (CHR) of South India
Elettaria cardamomum (L.) Maton originated in the evergreen forests of the Western Ghats of South India. In order to compare the percentage of essential oil and its components of selected small cardamom landraces, the study was conducted at the Indian Cardamom Research Institute, Myladumpara, Idukki Dt. of Kerala. Essential oil components of nine farmer's varieties such as Njallani Green Gold, Thiruthali, Panikulangara Green Bold No.1, Wonder Cardamom, Elarajan, Arjun, Pappalu, PNS Vaigai, Pachaikkai; and ICRI-5 as control were compared to evaluate the quality of genotypes. Essential oil content was significantly higher in Najllani Green Gold (9.18%), followed by Wonder Cardamom (8.36%). GC-MS profiling identified twenty-five compounds contributing to 90-93% of essential oil. The higher percentage of 1,8-cineole was observed in PNS Vaigai (38.04%) and the control ICRI-5 (38.99%), while Panikulangara Green Bold No.1 had the lowest percentage (24.30%). α- terpinyl acetate was higher (43.39%) in Panikulangara Green Bold No.1 followed by Thiruthali (39.21%), and was lowest in ICRI-5 (35.97%). Panikulangara Green Bold 1 had a higher percentage of α-terpineol, Geranyl acetate, Geraniol and Linalyl acetate than other genotypes. The percentage of sabinene was higher in Njallani Green Gold (7.56%), and in the genotype, Elarajan (5.46%) was lowest. Due to the medicinal and flavour-contributing properties, the essential oil components can be used in medicinal and food industries.  
Valorization of Monoterpene Hydrocarbon Fraction of Essential Oil to High-Value Oxygenated Monoterpenoids by Solvent-Free Catalytic Modification Using 1%Pd-β-Zeolite
Monoterpene hydrocarbons are the unwanted, off-smelling fractions in most of the essential oils. Due to the absence of functional groups in monoterpene hydrocarbons, it is difficult to solubilize in common solvents such as water, ethanol, etc. Hence, this fraction is removed from the essential oil in deterpenation process before their application in formulations. Pinene (α-,β-), the monoterpene hydrocarbons are found in most of the essential oils. In the present work, pinene isomers are esterified to valuable compounds such as terpinyl acetate, bornyl acetate and fenchyl acetate. They are widely used as fragrance ingredients in various food and cosmetic products with improved organoleptic profiles. Hence, a solvent-free process has been developed for the selective conversion of pinene to terpinyl acetate and bornyl acetate using 1%Pd-β-Zeolite (ZE) at room temperature (30 °C). The different percentage of Pd loading over β-ZE was studied on the transformation of α-pinene. It was attained 98% of conversion with the selectivity to 54.2% of terpinyl acetate, and 34.8% of bornyl acetate at 30 °C in 2 h using 1%Pd-β-ZE. Similarly, the synthesized catalyst (1%Pd-β-ZE) has been shown excellent activity for α-pinene esterification under the 50 psi N 2 at 50 °C to produce 83% selectivity towards bornyl acetate. The esterification of monoterpene hydrocarbons-rich essential oils (salaiguggul, guggul, black pepper, rosemary, and nutmeg) were carried out at 30 °C with 1%Pd-β-ZE for selective transformation to bornyl acetate, terpinyl acetate, and fenchyl acetate. Since the reactions are carried out without any additional use of organic solvents, hence, makes the overall process quite attractive. This study will help to develop an eco-friendly strategy for the valorization of bicyclic monoterpene hydrocarbons-rich essential oils. Graphical Abstract
Impact of Edaphic and Climatic Factors on Thymus pulegioides Essential Oil Composition and Potential Prevalence of Chemotypes
Intraspecific chemical polymorphism is characteristic of essential oil bearing Thymus pulegioides (Lamiaceae). Soil chemical composition and climatic conditions can influence not only quantitative and qualitative composition of essential oils, but also on prevalence of different chemotypes in space. The purpose of study was to determine the impact of edaphic and climatic factors on T. pulegioides essential oil composition and potential chemotypes prevalence. It were investigated 131 habitats of T. pulegioides in all ten climatic sub-districts of Lithuania. Essential oils were isolated by hydrodistillation and analysed by GC-FID and GC-MS. The content of humus was estimated by oxidation method, the content of mobile potassium (K2O) and mobile phosphorus (P2O5)—flame photometry using 0.2 M HCl solution, the soil pH—electrometrically and 15 elements of soil—by energy-dispersive X-ray fluorescence. The meteorological data (temperature, rainfall, photosynthetically active solar radiation and sunshine duration) were obtained from the meteorological bulletins. Results showed that humus in soil positively, manganese and cobalt—negatively influenced on the essential oil accumulation in T. pulegioides. Carvacrol was the most common compound in the essential oil of T. pulegioides; higher amounts of sulphur and mobile phosphorus, lower amounts of sodium in soil, higher rainfall in blooming period are favourable for this compound and for potential prevalence of carvacrol chemotype. Geraniol was frequent in the eastern and the central part of Lithuania, where the temperature in vegetation season is higher, and in soils characterised by higher and lower amounts of sodium and chlorine, respectively. Thymol, linalool and α-terpinyl acetate were rare. Edaphic and climatic conditions can differently influence on essential oil yield and chemical composition of species as well as on potential prevalence of different chemotypes of same species in space.
α-Terpinyl Acetate: Occurrence in Essential Oils Bearing Thymus pulegioides, Phytotoxicity, and Antimicrobial Effects
The aim of this study was to evaluate occurrence of T. pulegioides α-terpinyl acetate chemotype, as source of natural origin α-terpinyl acetate, to determine its phytotoxic and antimicrobial features. Were investigated 131 T. pulegioides habitats. Essential oils were isolated by hydrodistillation and analyzed by GC-FID and GC-MS. Phytotoxic effect of essential oil of this chemotype on monocotyledons and dicotyledons through water and air was carried out in laboratory conditions; the broth microdilution method was used to screen essential oil effect against human pathogenic microorganisms. Results showed that α-terpinyl acetate was very rare compound in essential oil of T. pulegioides: it was found only in 35% of investigated T. pulegioides habitats. α-Terpinyl acetate (in essential oil and pure) demonstrated different behavior on investigated plants. Phytotoxic effect of α-terpinyl acetate was stronger on investigated monocotyledons than on dicotyledons. α-Terpinyl acetate essential oil inhibited seeds germination and radicles growth for high economic productivity forage grass monocotyledon Poa pratensis, but stimulated seed germination for high economic productive forage legume dicotyledon Trifolium pretense. α-Terpinyl acetate essential oil showed high antimicrobial effect against fungi and dermatophytes but lower effect against bacteria and Candida yeasts. Therefore, T. pulegioides α-terpinyl acetate chemotype could be a potential compound for developing preventive measures or/and drugs for mycosis.
Development of biodegradable PLA composites and tangerine peel flour with improved toughness containing a natural-based terpenoid
The present work reports on the development of environmentally friendly, completely biodegradable wood plastic composites based on polylactide (PLA) and tangerine peel flour (TPF), plasticized by α-terpinyl acetate (TA). The TPF varied in the 10-30 wt% while the PLA to TA (wt%/wt%) was set to 4 (i. e., 25 wt% TA plasticizer was added with regard to the PLA wt%). The developed composites were processed by extrusion and injection molding. The composites presented excellent elongation at break, achieving values of 300% for the PLA+TA sample. Elongation at break values of 200% for the PLA composite with 10 wt% TPF and plasticized with TA were obtained. Those results were confirmed by the appearance of filament-like structures observed in field emission scanning electron microscopy images. Differential scanning calorimetry and dynamic mechanical thermal analysis revealed a remarkable decrease in the glass transition temperature of PLA as a result of the plasticizing effect of TA. Glass transition was reduced from 63 °C down to 41°C approximately. This implied an increase in the ductility of the material. The samples with TPF exhibited a dark brown color, making them perfect for wood plastic composite applications. Water contact angle results show that TA and TPF change the wetting properties of the obtained composites. A general decrease in the water contact angle was observed with the addition of TPF and TA. Finally, disintegration tests proved that the developed composites are fully biodegradable. All the samples except for neat PLA achieved 100% disintegration in controlled compost soil conditions after 5 weeks, while neat PLA reached complete disintegration in 6 weeks.
Content and Chemical Composition of Essential Oil from Cardamom (Elettaria cardamomum (L.) Maton)
This study was conducted to determine and compare the essential oil content and composition of eight samples of cardamom (Elettaria cardamomum). The yield of essential oils isolated by hydrodistillation from the dried fruits varied from 4 to 56 mL kg-1. Chemical analysis by gas chromatography coupled with mass spectrometry (GC/MS) revealed the presence of 21-48 compounds accounting for 98.88- 99.98 % of the total essential oils. Alpha-terpinyl acetate was the most abundant compound in all samples (35.99-62.28 %), followed by 1,8cineole (0.24-30.62 %), a-terpineol (2.18-16.75 96), linalool (0.81-7.25 %), and linalyl acetate (1.49-4.67 %). The radar plots easily distinguished cardamom samples. Multivariate principal component analysis (PCA) was used to evaluate the phytochemical diversity of the cardamom fruits. The results presented provide a first insight into the substantial differences in the yield and composition of the essential oil of commercially available cardamom fruits and underline the superior quality of the whole fruit compared to the powdered form.
Antifungal activity of bio-active cell-free culture extracts and volatile organic compounds (VOCs) synthesised by endophytic fungal isolates of Garden Nasturtium
Antimicrobial resistance in fungal pathogens (both human and plant) is increasing alarmingly, leading to massive economic crises. The existing anti-fungal agents are becoming ineffective, and the situation worsens on a logarithmic scale. Novel antifungals from unique natural sources are highly sought to cope sustainably with the situation. Metabolites from endophytic microbes are the best-fitted alternatives in this case. Endophytes are the untapped sources of ‘plants’ internal microbial population’ and are promising sources of effective bio-therapeutic agents. Fungal endophytes were isolated from Tropaeolum majus and checked for antifungal activity against selected plant and human pathogens. Bioactive metabolites were identified through chromatographic techniques. The mode of action of those metabolites was evaluated through various spectroscopic techniques. The production of antifungal metabolite was optimized also. In particular VOCs (volatile organic compounds) of TML9 were tested in vitro for their anti-phytopathogenic activity. Ethyl acetate (EA) extract of cell-free culture components of Colletotrichum aenigma TML3 exhibited broad-spectrum antifungal activity against four species of Candida and the major constituents reported were 6-pentyl-2H-pyran-2-one, 2-Nonanone, 1 propanol 2-amino. The volatile metabolites, trans-ocimene, geraniol, and 4-terpinyl acetate, produced from Curvularia lunata TML9, inhibited the growth of some selected phyto pathogens. EA extract hampered the biofilm formation, minimised the haemolytic effect, and blocked the transformation of Candida albicans (MTCC 4748) from yeast to hyphal form with a Minimum Fungicidal Concentration (MFC) of 200–600 µg mL −1 . Central carbohydrate metabolism, ergosterol synthesis, and membrane permeability were adversely affected and caused the lethal leakage of necessary macromolecules of C. albicans . Volatile metabolites inhibited the growth of phytopathogens i.e., Rhizoctonia solani , Alternaria alternata , Botrytis cinerea , Cercospora beticola , Penicillium digitatum , Aspergillus fumigatus , Ceratocystis ulmi , Pythium ultimum up to 89% with an IC 50 value of 21.3–69.6 µL 50 mL −1 and caused leakage of soluble proteins and other intracellular molecules. Citrusy sweet odor volatiles of TML9 cultured in wheat-husk minimised the infections of Penicillium digitatum (green mold), in VOC-exposed sweet oranges ( Citrus sinensis ). Volatile and non-volatile antifungal metabolites of these two T. majus endophytes hold agricultural and pharmaceutical interests. Metabolites of TML3 have strong anti-Candida activity and require further assessment for therapeutic applications. Also, volatile metabolites of TML9 can be further studied as a source of antifungals. The present investigational outcomes bio-prospects the efficacy of fungal endophytes of Garden Nasturtium.
Antimicrobial Activity of Selected Essential Oils against Selected Pathogenic Bacteria: In Vitro Study
The worldwide problem of infectious diseases has appeared in recent years, and antimicrobial agents are crucial in reducing disease emergence. Nevertheless, the development and distribution of multidrug-resistant (MDR) strains in pathogenic bacteria, such as Escherichia coli, Staphylococcus aureus, Salmonella Typhi and Citrobacter koseri, has become a major society health hazard. Essential oils could serve as a promising tool as a natural drug in fighting the problem with these bacteria. The current study aimed to investigate the antimicrobial effectiveness of tea tree (Melaleuca alternifolia (Maiden and Betche) Cheel), rosemary (Rosmarinus officinalis L.), eucalyptus (Eucalyptus obliqua L’Hér.), and lavender (Lavandula angustifolia Mill) essential oils. The antimicrobial properties of essential oils were screened against four pathogenic bacteria, E. coli, S. aureus, S. Tyhpi, and C. koseri, and two reference bacterial strains, while for the testing, the agar well diffusion method was used. Gas chromatography (GC) and gas chromatography–mass spectrometric (GC–MSD) analyses were performed on essential oils. The obtained results showed that M. alternifolia essential oil is the richest in terpinen-4-ol, R. officinalis and E. oblique essential oils in 1,8-cineole, and L. angustifolia essential oil in α-terpinyl acetate. In addition, the main bioactive compounds present in the essential oil of tea tree are rich in α-pinene (18.38%), limonene (7.55%) and γ-terpinene (14.01%). The essential oil of rosemary is rich in α-pinene (8.38%) and limonene (11.86%); eucalyptus essential oil has significant concentrations of α-pinene (12.60%), p-cymene (3.24%), limonene (3.87%), and γ-terpinene (7.37%), while the essential oil of lavender is rich in linalool (10.71%), linalool acetate (9.60%), α-terpinyl acetate (10.93%), and carbitol (13.05%) bioactive compounds, respectively. The obtained results from the in vitro study revealed that most of the essential oils exhibited antimicrobial properties. Among the tested essential oils, tea tree was discovered to demonstrate the strongest antimicrobial activity. The recorded MIC of S. Typhi was 6.2 mg/mL, 3.4 mg/mL of C. koseri, 3.1 mg/mL of E. coli, and 2.7 mg/mL of E. coli ATCC 25922, compared to M. alternifolia. Similarly, only S. aureus ATCC 25923 showed antimicrobial activity towards R. officinalis (1.4 mg/mL), E. oblique (2.9 mg/mL), and L. angustifolia (2.1 mg/mL). Based on the obtained results, it is possible to conclude that tea tree essential oil might be used as an ecological antimicrobial in treating infectious diseases caused by the tested pathogens.
Comparative Study of Chemical Composition and Antioxidant Activity of Essential Oils and Crude Extracts of Four Characteristic Zingiberaceae Herbs
The ginger family (Zingiberaceae) includes plants that are known worldwide to have a distinctive smell and taste, which are often used as spices in the kitchen, but also in various industries (pharmaceutical, medical, and cosmetic) due to their proven biological activity. The aim of this study was to investigate and compare the chemical composition and antioxidant activity (AA) of essential oils (EOs) of four characteristic ginger species: Elettaria cardamomum L. Maton (cardamom), Curcuma Longa L. (turmeric), Zingiber Officinale Roscoe (ginger), and Alpinia Officinarum Hance (galangal). Furthermore, the total phenolic content (TPC) and AA of crude extracts obtained after using ultrasound-assisted extraction (UAE) and different extraction solvents (80% ethanol, 80% methanol and water) were evaluated. A total of 87 different chemical components were determined by GC-MS/MS in the EOs obtained after hydrodistillation, 14 of which were identified in varying amounts in all EOs. The major compounds found in cardamom, turmeric, ginger, and galangal were α-terpinyl acetate (40.70%), β-turmerone (25.77%), α-zingiberene (22.69%) and 1,8-cineol (42.71%), respectively. In general, 80% ethanol was found to be the most effective extracting solvent for the bioactivities of the investigated species from the Zingiberaceae family. Among the crude extracts, ethanolic extract of galangal showed the highest TPC value (63.01 ± 1.06 mg GA g−1 DW), while the lowest TPC content was found in cardamom water extract (1.04 ± 0.29 mg GA g−1 DW). The AA evaluated by two different assays (ferric-reducing antioxidant power-FRAP and the scavenging activity of the cationic ABTS radical) proved that galangal rhizome is the plant with the highest antioxidant potential. In addition, no statistical difference was found between the AA of turmeric and ginger extracts, while cardamom rhizome was again inferior. In contrast to the crude extracts, the EOs resulted in significantly lower ABTS and FRAP values, with turmeric EO showing the highest AA.
A closer look at sex pheromone autodetection in the Oriental fruit moth
Female moths emit sex pheromone to attracts males, and although they are not attracted to their own sex pheromone, they appear to detect it as it affects their behavior. In order to elucidate the mechanism of pheromone “autodetection” we compared responses of olfactory receptor neurons (ORNs) of male and female Grapholita molesta , a species with reported pheromone autodetection. Two concentrations of the major ( Z 8-12:Ac) and minor ( E 8-12:Ac) sex pheromone components, a plant-volatile blend containing methyl salicylate, terpinyl acetate and ( E )-β-farnesene, and the male-produced hair-pencil (i.e., courtship) pheromone (ethyl trans-cinnamate) were tested in 45 male and 305 female ORNs. Hierarchical cluster analysis showed radically different peripheral olfactory systems between sexes that could be linked to their specific roles. In males 63% of the ORNs were tuned specifically to the major or minor female sex pheromone components, and 4% to the plant volatile blend, while the remaining 33% showed unspecific responses to the stimulus panel. In females 3% of the ORNs were specifically tuned to the male hair-pencil pheromone, 6% to the plant volatile blend, 91% were unspecific, and no ORN was tuned their own sex pheromone components. The lack of sex pheromone-specific ORNs in females suggests that they are not able to discriminate pheromone blends, and thus pheromone autodetection is unlikely in this species. We discuss our results in the context of the methodological limitations inherent to odor stimulation studies.