scholarly journals Essential Oil of Plectranthus tenuicaulis Leaves from Gabon, Source of (R),(E)-6,7-Epoxyocimene. An Unusual Chemical Composition within the Genus Plectranthus

2011 ◽  
Vol 6 (3) ◽  
pp. 1934578X1100600 ◽  
Author(s):  
Huguette Agnaniet ◽  
Abdelhamid Agrebi ◽  
Raphaël Bikanga ◽  
Thomas Makani ◽  
Jacques Lebibi ◽  
...  

Water distilled essential oils from leaves of Plectranthus tenuicaulis (Hook. f.) J. K. Morton collected in Gabon were analyzed using GC-FID and GC-MS. The main constituent, unusual within the genus Plectranthus, was isolated and formally identified as being the (+)-( R)-enantiomer of ( E)-6,7-epoxyocimene [( E)-myroxide]. This enantiomer, which represents about 75% of the essential oil, has been previously identified as a pheromone emitted by the male fruit-spotting bug Amblypelta nitida; this insect is responsible of destruction of most fruit crops in tropical and subtropical areas. The potential application of P. tenuicaulis essential oil in crop protection programs is discussed and the atypical chemical profile of the gabonese essential oil is compared with those previously reported in the genus Plectranthus (or Coleus).

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 988 ◽  
Author(s):  
Olga Kosakowska ◽  
Zenon Węglarz ◽  
Ewelina Pióro-Jabrucka ◽  
Jarosław L. Przybył ◽  
Karolina Kraśniewska ◽  
...  

Greek oregano and common oregano were compared in respect of the antioxidant and antibacterial activity of the corresponding essential oils and hydroethanolic extracts in relation with their chemical profile. The chemical composition of essential oils was determined by GC-MS and GC-FID, while extracts (phenolic acids and flavonoids fractions) were analyzed by HPLC-DAD. Based on given volatiles, the investigated subspecies represented two chemotypes: a carvacrol/γ-terpinene/p-cymene type in the case of Greek oregano and a sabinyl/cymyl type rich in terpinen-4-ol in common oregano. Within non-volatile phenolic compounds, rosmarinic acid appeared to dominate in both subspecies. Lithospermic acid B, chlorogenic acid and isovitexin were present only in Greek oregano extracts. However, the total content of flavonoids was higher in common oregano extracts. The essential oil and extract of Greek oregano revealed visibly stronger antibacterial activity (expressed as MIC and MBC) than common oregano, whereas the antioxidant potential (determined by DPPH, ABTS and FRAP) of these extracts was almost equal for both subspecies. In the case of Origanum plants, the potential application of essential oils and extracts as antiseptic and antioxidant agents in the food industry should be preceded by subspecies identification followed by recognition of their chemotype concerning both terpene and phenolics composition.


2015 ◽  
Vol 10 (4) ◽  
pp. 1934578X1501000
Author(s):  
Yu-Chang Su ◽  
Kuang-Ping Hsu ◽  
Eugene I-Chen Wang ◽  
Chen-Lung Ho

In this study, anti-mildew activities of the essential oils of the leaves, wood, twigs, flowers, and their constituents from Michelia compressa var. formosana were evaluated in vitro against 7 mildew fungi. The main compounds responsible for the anti-mildew activities were isolated and identified. The essential oils from the fresh leaves, wood, twigs, and flowers of M. compressa var. formosana were isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. The essential oil yield from the flowers was the highest, and the oils obtained from the 4 parts of the tree were composed mainly of sesquiterpenoids. The leaf oil consisted primarily of α-cadinol (18.9%) and germacrene D (18.5%); the twig oil's main constituent was α-cadinol (19.1%); the wood oil's major components were α-cadinol (25.7%) and β-eudesmol (20.2%); and the flower oil contained α-cadinol (11.4%). Comparing the anti-mildew activities of the oils suggested that wood oil was the most effective. Further fractionation of the wood oil produced α-cadinol, β-eudesmol, τ-cadinol, and elemol. The 4 compounds exhibit very strong anti-mildew activities, and these in descending order are α-cadinol, elemol, β-eudesmol, and τ-cadinol. For the anti-mildew activities of the wood oil, the active source compounds were determined to be α-cadinol, elemol, β-eudesmol, and τ-cadinol.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5476 ◽  
Author(s):  
Delmacia G. de Macêdo ◽  
Marta Maria A. Souza ◽  
Maria Flaviana B. Morais-Braga ◽  
Henrique Douglas M. Coutinho ◽  
Antonia Thassya L. dos Santos ◽  
...  

Medicinal plants play a crucial role in the search for components that are capable of neutralizing the multiple mechanisms of fungal resistance. Psidium salutare (Kunth) O. Berg is a plant native to Brazil used as both food and traditional medicine to treat diseases and symptoms such as stomach ache and diarrhea, whose symptoms could be related to fungal infections from the genus Candida. The objective of this study was to investigate the influence of seasonal variability on the chemical composition of the Psidium salutare essential oil, its antifungal potential and its effect on the Candida albicans morphogenesis. The essential oils were collected in three different seasonal collection periods and isolated by the hydrodistillation process in a modified Clevenger apparatus with identification of the chemical composition determined by gas chromatography coupled to mass spectrometry (GC/MS). The antifungal assays were performed against Candida strains through the broth microdilution method to determine the minimum fungicidal concentration (MFC). Fungal growth was assessed by optical density reading and the Candida albicans dimorphic effect was evaluated by optical microscopy in microculture chambers. The chemical profile of the essential oils identified 40 substances in the different collection periods with γ-terpinene being the predominant constituent. The antifungal activity revealed an action against the C. albicans, C. krusei and C. tropicalis strains with an IC50 ranging from 345.5 to 2,754.2 µg/mL and a MFC higher than 1,024 µg/mL. When combined with essential oils at sub-inhibitory concentrations (MIC/16), fluconazole had its potentiated effect, i.e. a synergistic effect was observed in the combination of fluconazole with P.salutare oil against all Candida strains; however, for C. albicans, its effect was reinforced by the natural product in all the collection periods. The results show that the Psidium salutare oil affected the dimorphic transition capacity, significantly reducing the formation of hyphae and pseudohyphae in increasing concentrations. The results show that P. salutare oil exhibits a significant antifungal activity against three Candida species and that it can act in synergy with fluconazole. These results support the notion that this plant may have a potential use in pharmaceutical and preservative products.


2013 ◽  
Vol 8 (2) ◽  
pp. 1934578X1300800
Author(s):  
Igor Jerković ◽  
Maja Marasović ◽  
Zvonimir Marijanović ◽  
Kroata Hazler Pilepić ◽  
Željan Maleš ◽  
...  

The aerial parts of Hypericum richeri Vill. subsp. grisebachii (Boiss.) Nyman were collected from two different locations in Croatia and subjected to hydrodistillation. GC/FID and GC/MS analysis of the isolated essential oils revealed 64 compounds representing 94.7% and 98.2% of the total oils. Predominant constituents in both samples were: germacrene D (10.9%; 6.0%), bicyclogermacrene (4.7%; 3.5%), α-pinene (6.8%; 6.9%), β-pinene (8.1%; 5.1%), decanoic acid (4.5%; 6.8%), β-caryophyllene (3.3%; 7.5%), δ-cadinene (7.0%; 4.4%), spathulenol (6.0%; 9.5%) and tetracosane (3.1%; 5.8%). Comparison of both samples revealed similarity in the chemical composition with minor fluctuations of constituent percentages. The chemical profile of Croatian oils was in general similar to those reported for other geographic areas regarding major mono- and sesquiterpene constituents. However, spathulenol, 5-cadinene and bicyclogermacrene were more abundant in Croatian oils. The presence of decanoic acid (4.5%; 6.8%) in Croatian oils was the major difference between acids and fatty acids derivatives. Higher abundance of alkanes (particularly tetracosane and docosane) was also noticed.


Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 636
Author(s):  
Nadjiya Merad ◽  
Vanessa Andreu ◽  
Slimane Chaib ◽  
Ronaldo de Carvalho Augusto ◽  
David Duval ◽  
...  

Chemical composition and herbicidal, antifungal, antibacterial and molluscicidal activities of essential oils from Choukzerk, Eryngium triquetrum, and Alexander, Smyrnium olusatrum, from western Algeria were characterized. Capillary GC-FID and GC/MS were used to investigate chemical composition of both essential oils, and the antifungal, antibacterial, molluscicidal and herbicidal activities were determined by % inhibition. Collective essential oil of E. triquetrum was dominated by falcarinol (74.8%) and octane (5.6%). The collective essential oil of S. olusatrum was dominated by furanoeremophilone (31.5%), furanodiene+curzurene (19.3%) and (E)-β-caryophyllene (11%). The E. triquetrum oil was tested and a pure falcarinol (99%) showed virtuous herbicidal and antibacterial activities against potato blackleg disease, Pectobacteriumatrosepticum, and Gram-negative soil bacterium, Pseudomonas cichorii (85 and 100% inhibition, respectively), and high ecotoxic activity against brine shrimp, Artemia salina, and the freshwater snail, Biomphalaria glabrata, with an IC50 of 0.35 µg/mL and 0.61 µg/mL, respectively. Essential oil of S. olusatrum showed interesting antibacterial and ecotoxic activity and good herbicidal activity against watercress seeds, Lepidium sativum (74% inhibition of photosynthesis, 80% mortality on growth test on model watercress), while the furanoeremophilone isolated from the oil (99% pure) showed moderate herbicidal activity. Both oils showed excellent antifungal activity against Fusarium. Both oils and especially falcarinol demonstrated good potential as new biocontrol agents in organic crop protection.


2006 ◽  
Vol 1 (5) ◽  
pp. 1934578X0600100 ◽  
Author(s):  
Walber H. F. Ribeiro ◽  
Jackson N. Vasconcelos ◽  
Angela M. C. Arriaga ◽  
Maria C. F. de Oliveira ◽  
Manoel Andrade-Neto ◽  
...  

The essential oils obtained by hydrodistillation of the leaves, stems, and shoots of Tephrosia toxicaria Pers (Papilionaceae) were analyzed using GC and GC/MS. Germacrene D was the major component (20.7-33.3 %) of the oils of leaves and shoots, whereas spathulenol was the main constituent (42.3%) of the stem oil. The essential oils from the leaves and stems, when tested for activity against mosquito larvae (Aedes aegypti), gave LC 50 values of 81.3 ± 2.9 and 63.1 ± 1.0 ppm, respectively.


2020 ◽  
Vol 71 (7) ◽  
pp. 307-315
Author(s):  
Mihaela Bogdan ◽  
Simona Bungau ◽  
Delia Mirela Tit ◽  
Lucian Copolovici ◽  
Tapan Behl ◽  
...  

In this research, the variations in the chemical composition of the Lavandula angustifolia Mill. essential oil, the Romanian variety Moldoveanca 4, obtained from the same culture, in the same harvesting and extraction conditions, during the years 2016-2018, representing the years 2-4 of culture. Lavandula angustifolia Mill. flowers were supplied from an ecological-crops from N-E Romania and the essential oils were obtained by hydro distillation of freshly harvested flowers. To determine the chemical composition, the essential oil was semi-quantitatively analysed by using gas chromatography coupled with mass spectrometry (GC-MS). In all the samples, 30 organic compounds were identified, linalool and linalyl acetate being in similar concentrations (23.51-27.39% for linalool and 26.60-40.66% for linalyl acetate). Changes in chemical composition were observed in 2017 and 2018. Also, in 2017 was determined an increase in the quantity of linalyl acetate (from 26.60 to 40.66 %), and a slight decrease in linalool content; in 2018, the concentration in linalyl acetate remained approximately the same as in 2017 (38.03 versus 40.66 %) and there was an increase in linalool compared to the previous years (27.39 %, compared to 23.51 % in 2017 and 26.22 % in 2016). The chemical composition of the essential oils obtained from flowers of Lavandula angustifolia L., Moldoveanca 4 variety, showed substantial changes of the chemical profile describing the compounds during the analysed three years, as was determined by GC-MS analyses.


2018 ◽  
Vol 16 (S1) ◽  
pp. S155-S163 ◽  
Author(s):  
S. Mehalaine ◽  
O. Belfadel ◽  
T. Menasria ◽  
A. Messaili

The present study was carried out to determine, for the first time, the chemical composition and antibacterial activity of essential oils derived from the aerial parts of three aromatic plants Thymus algeriensis Boiss & Reut, Rosmarinus officinalis L., and Salvia officinalis L. growing under semiarid conditions. The essential oils were chemically analyzed and identified by gas chromatography (GC) and GC/ mass spectrometry (GC/MS) and their antimicrobial activity was individually evaluated against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using both agar disk diffusion and agar dilution methods. The major constituents of Thymus algeriensis essential oil were identified as camphor (13.62%), 1,8-cineol (6.00%), borneol (5.74%), viridiflorol (4.00%), and linalool (3.93%). For Rosmarinus officinalis essential oil, 48 compounds were characterized, of which the main constituents were camphor (17.09%), Z-β-ocimene (10.88%), isoborneol (9.68%), α-bisabolol (7.89%), and borneol (5.11%). While, Salvia officinalis essential oil was characterized by β-thujone (16.44%), followed by viridiflorol (10.93%), camphor (8.99%), 1,8-cineol (8.11%), trans-caryophyllene (5.85%), and α-humulene (4.69%) as the major components. Notably, results from antibacterial screening indicated that Thymus algeriensis and Salvia officinalis essential oils exhibited a strong inhibitory effect against both Escherichia coli and Staphylococcus aureus compared to Rosmarinus officinalis essential oil. Further, less activity was recorded against Pseudomonas aeruginosa for the three tested essential oils.


2020 ◽  
Vol 10 (3) ◽  
pp. 272-278
Author(s):  
Ardalan Pasdaran ◽  
Satyajit D. Sarker ◽  
Lutfun Nahar ◽  
Azadeh Hamedi

Background: The essential oil from the Acantholimon genus have been an integral part of the traditional food additive in Middle East. Most of the plants in Acantholimon genus have not been studied scientifically. The aim of this study is to investigate the chemical composition, antibacterial, insecticidal and anti-oxidant activities of three Acantholimon species including Acantholimon atropatanum, A. gilliatii and A. tragacanthium. Method: The essential oils of the aerial parts were extracted by hydrodistillation. Chemical constitutions were identified by gas chromatography- mass spectroscopy technique, also their toxicities were assessed against the two important grain products pests, Oryzeaphilus mercator and Tribolium castaneum. Antibacterial activity was assessed against the three foodborne bacteria that include Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus based on the disc diffusion assay. Free-radical-scavenging property was identified based on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Results: 2-hexahydrofarnesyl acetone was the main compound in A. gilliatii and A. tragacanthium, whilst farnesyl acetone, heptacosane and germacrene D were the principal components of A. atropatanum essential oil. These oils exhibited 40-90% mortality of O. mercator and/or T. castaneum at a dose of 12 μl/l air after 48h of exposure, and exhibited significant free-radicalscavenging property (RC50 = 3.7 × 10-3 - 8.3 × 10-3 mg/ml). The oils of A. tragacanthium and A. gilliatii showed a weaker antibacterial activity compared to A. atropatanum. Conclusion: A. atropatanum, A. gilliatii and A. tragacanthium essential oils had significant insecticidal and anti-oxidant properties. They also showed week to moderate antibacterial activity against P. aeruginosa and S. aureus.


Author(s):  
Mansureh Ghavam ◽  
Afsaneh Afzali ◽  
Maria Manconi ◽  
Gianluigi Bacchetta ◽  
Maria Letizia Manca

Abstract Background Essential oil of Rosa × damascena Herrm. is one of the most valuable and important raw materials for the flavor and fragrance industry. The cultivation of this plant has ancient origins, and Kashan was one of the first mountainous regions of Iran dealing with the cultivation of R. × damascena. In this study, both chemical composition and antimicrobial activity of different rose essential oils obtained from five mountainous areas of Kashan region (Maragh, Qamsar, Sadeh, Javinan, and Kamoo) has been investigated along with the influence of the environmental conditions on these properties. Results Results showed that yield and chemical composition of essential oils obtained from Rosa × damascena were significantly affected by the collection area. In particular, the yield of oils varied from ~0.08 to ~0.132% and citronellol (36.70-9.18%), geraniol (12.82-0.47%), nonadecane (22.73-10.36%), heneicosane (31.7-11.43%), and 1-nonadecene (6.03-3.93%) have been detected as main compounds in all the plants collected, but at different concentrations depending on the collection area. The best fragrance and the highest yield were found in the oil from Kamoo area. Similarly to the chemical composition, the antimicrobial activity of the essential oils was affected by their origin, and essential oil obtained from plants collected from Kamoo area disclosed the highest antibacterial and antifungal efficacy. Its inhibition halos were 17.33±0.58 mm against Aspergillus brasiliensis, 15.67±0.58 mm against Staphylococcus aureus, and 12.33±0. 58 mm against Streptococcus pyogenes. Essential oils of R. damascena were also effective against Gram-negative Pseudomonas aeruginosa and they had a MIC value of 62.50 μg/mL irrespective of the collection area (except the oil from Javinan area). On the contrary, the highest antifungal power against Candida albicans yeast was reached using the essential oil obtained from plants collected in Javinan region (MIC and MBC ~62.50 μg/mL). Conclusions Overall results underline the influence of environmental conditions of the different areas of Kashan region, on the chemical composition of and antimicrobial activity of the essential oils of Rosa × damascena. In addition, results disclosed that Kamoo seemed to be the most suitable area for the competitive cultivation of R. × damascena to the intensive production of aromatic flower oil and natural antimicrobial essential oils.


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