Comparison of different methods for extraction from Tetraclinis articulata: Yield, chemical composition and antioxidant activity

In the present study, three techniques of extraction: hydrodistillation (HD), solvent extraction (conventional ‘Soxhlet’ technique) and an innovative technique, i.e., the supercritical fluid extraction (SFE), were applied to ground Tetraclinis articulata leaves and compared for extraction duration, extraction yield, and chemical composition of the extracts as well as their antioxidant activities. The extracts were analyzed by GC–FID and GC–MS. The antioxidant activity was measured using two methods: ABTS and DPPH. The yield obtained using HD, SFE, hexane and ethanol Soxhlet extractions were found to be 0.6, 1.6, 40.4 and 21.2–27.4 g/kg respectively. An original result of this study is that the best antioxidant activity was obtained with an SFE extract (41 mg/L). The SFE method offers some noteworthy advantages over traditional alternatives, such as shorter extraction times, low environmental impact, and a clean, non-thermally-degraded final product. Also, a good correlation between the phenolic contents and the antioxidant activity was observed with extracts obtained by SFE at 9 MPa

Supercritical CO2 extraction of Tetraclinis articulata: chemical composition, antioxidant activity and mathematical modeling

Operating conditions for extraction from the leaves of Tetraclinis articulata using supercritical carbon diox-ide (SCCO2) were studied to focus on the feasibility of obtaining volatile and nonvolatile fractions throughthe use of different extraction pressures (90, 280 and 1000 bar). In addition, influence of temperature,static pretreatment and dynamic extraction durations, particle size and CO2flow rate were investigated.All extracts were analyzed by GC–FID/MS and their antioxidant activity was measured using ABTS•+andDPPH•methods. Conventional hydrodistillation (HD) was also performed for comparison. At high CO2pressure (280 and 1000 bar), the amount of phenolics in the extracts was higher (respectively 102.03and 267.90 GAE mg/g) than for HD and supercritical fluid extraction (SFE) at 90 bar (respectively 8.89 and9.70 GAE mg/g). Correlatively, high antioxidant activity was found for high pressure SFE. Surprisingly, forextracts obtained by SFE at 90 bar, despite very low phenolic content, significant antioxidant activity wasobserved, while essential oil obtained by HD, which presented also low phenolic content, exhibited lowantioxidant activity.Physical aspects were only investigated for the low pressure supercritical extraction (90 bar) process.Qualitative assessment of kinetic curves together with their modeling revealed that the extraction pro-cess was mainly limited by the thermodynamic equilibrium of easily accessible solutes but where axialdispersion was significant. From this result a simple extrapolation procedure was proposed

Study of essential oils adsorption on three phosphate fertilizers

In this paper, we report the study of essential oils adsorption on three phosphate fertilizers: mono-ammonium phosphate, di-ammonium phosphate and triple super phosphate with the aim to prepare a bi-function product which can be used as a fertilizer and bio-pesticides. Essential oils were isolated by steam distillation from Eucalyptus salubris and Artemisia herba.alba and analysed by GC-MS and GC-FID. About 12 and 22 constituents were identified and quantified in these oils, respectively. The kinetic adsorption study of essential oils showed that DAP and TSP exhibited high adsorption capacities compared with MAP (DAP (0.143 g/g) and TSP (0.139 g/g) for Eucalyptus salubris essential oil and (DAP (0.135 g/g) and TSP (0.134 g/g) for Artemisia herba-alba essential oil). The adsorption isotherms of all identified components in the Eucalyptus salubris essential oil were determined and the Langmuir and Freundlich models were used to describe the experimental data. Langmuir model fitted well the isotherms of the majority of the essential oil components (1,8-cineole, α-pinene, β-Pinene, isopinocarveol, β-eudesmol, α-phellandrene, Pinocarvone, P-cymene and Spathulenol) and only Terpineol and Globulol isotherm data followed the Freundlich model. The selectivity was affected by the abundance of each component in the crude essential oil and the polarity of terpenic components

Chemical composition and antimicrobial and antioxidant activities of Tunisian, France and Austrian Laurus nobilis (Lauraceae) essential oils

Essential oil (EO) of Laurus nobilis, from Tunisian, France and Austrian were screened for their chemical composition, antioxidant and antimicrobial activities and compared. GC-MS analysis showed that leaves of Tunisian L. nobilis had camphor (34.43%), 1,8-cineole (20.21%) and α-terpineol (7%) as major components. France and Austrian EOs had a high content of 1,8-cineole (45.8% and 43.4%, respectively) followed by bornyl acetate (13.8% and 17.7% respectively) and methyl eugenol (7.7% and 10.9% respectively). Antioxidant potential was measured by ABTS and DPPH tests. Tunisian L. nobilis EO showed greater radical scavenging by ABTS activity (IC50=44.8±0.1 mg/L) than the France and Austrian EOs (76.4±3.2 mg/L and 81.4±4.0 mg/L, respectively). However, for DPPH test system, French and Austrian EOs activities were excellent (IC50=176.1±5.1 mg/L and 236.3±2.9 mg/L respectively) then Tunisian L. nobilis EO (IC50=2859.7±99.0 mg/L). A good Antimicrobial activity was observed on the yeasts and fungi for all EOs. Tunisian laurel EO show a better antibacterial activity against gram-negative bacteria (Klebsiella pneumonial, E. coli and Salmonella enterica CMI: 0.004 mg/ml) than gram-positive ones (Bacilus subtilis, Staphylococcus aureus and Listeria monocytogenes CMI: 0.01 mg/ml). A significant antifungal activity of Tunisian EO was also observed against fungi and yeasts species (CMI: 0.004 mg/ml). France essential oil shows better activities against all organisms tested wail Austrian oil activity is more important against yeasts species tested and Mucor ramannianus (fungi).  Chemical composition, antimicrobial and antioxidant activity of Tunisian L. nobilis essential oil, were different from that of France and Austrian and it give the opportunity for its uses in new pharmaceuticals and natural therapies of infectious diseases

Extraction et purification de substances naturelles (comparaison de l'extraction au CO2-supercritique et des techniques conventionnelles)

Ce travail concerne l'extraction de substances naturelles d'origine végétale en utilisant des procédés verts tels que l'extraction au CO2 supercritique (CO2-SC, de 90 à 1000 bar) et l'extraction à l'eau sub-critique (SWE). Ces procédés sont une alternative à l'hydrodistillation (HD) et l'extraction par solvant (SE) traditionnellement utilisés dans l'industrie des produits naturels. La majorité du travail a été réalisée sur l'espèce Tetraclinis articulata où les performances des procédés, CO2-SC , HD, SWE et SE, ont été optimisées puis comparées en termes de rendement, composition chimique, durée , et en particulier activité antioxydante des extraits (évaluée par les tests ABTS + and DPPH). La plus forte activité antioxydente a été mise en évidence pour les extraits CO2-SC, ceci étant très probablement dû à une moindre dégradation thermique, comme l'a indiqué la comparaison des compositions chimiques. La CO2-SC basse pression (90 bar) a permis d'obtenir un extrait de bonne qualité et, pour ce cas, une modélisation a été proposée pour comprendre et identifier le mécanisme limitant qui s'est avéré être l'équilibre solide-fluide. La modélisation de l'hydrodistillation a également été proposée, basée sur le modèle de Sovová . Ensuite, l'approche a été étendue à d'autres plantes : Eucalyptus cinerea, Eucalyptus Camaldulensis, Cypres sempervirens et callitris.This work has dealt with extraction of natural substances from plants using green processes such as supercritical CO2 extraction (CO2-SC from 90 to 1000 bar) and extraction with subcritical water (SWE). These processes are an alternative to hydrodistillation (HD) and solvent extraction (SE) traditionally used in the natural products industry. Main part of the work was done on the species Tetraclinis articulata, and performance of the different processes, CO2-SC, HD,SWE and SE, were optimized and compared in terms of yield, chemical composition, duration ... and especially antioxidant activity of extracts (assessed by the ABTS+ and DPPH tests). CO2-SC extracts exhibited the strongest antioxidant activity and comparison of chemical compositions of the different extracts indicated that this is very probably due to lower thermal degradation of active molecules. For low pressure CO2-SC (90 bar), a model was proposed to understand and identify the limiting mechanism that proved to be solid-fluid equilibrium. For hydrodistillation, modelling, based on the Sovová 's model was also proposed. Then, the approach was extended to other plants: Eucalyptus cinerea and Eucalyptus camaldulensis, Cypres sempervirens and Callitris.TOULOUSE-INP (315552154) / SudocSudocFranceF

Chemical Composition and in vitro Antimicrobial and Antioxidant Activities of Citrus aurantium L. Flowers Essential Oil (Neroli Oil)

Neroli essential oil is extracted from the fragant blossoms of the bitter orange tree. It is one of the most widely used floral oils in perfumery. In this study chemical composition and in vitro antimicrobial and antioxidant activities of neroli oil are investigated. The essential oil of fresh Citrus aurantium L. Flowers (Neroli oil) cultivated in North East of Tunisia (Nabeul) were analyzed by GC-FID and GC-MS. About 33 compounds were identified, representing 99% of the total oil. Limonene (27,5%) was the main component followed by (E)-nerolidol (17,5%), α-terpinyl acetate (11,5%) and (E,E)-farnesol (8%). Antimicrobial activity was determined by Agar-well-diffusion method against 6 bacteria (3 Gran-positive and 3 Gram-negative), 2 yeasts and 3 fungi. Neroli oil exhibited a marked antibacterial activity especially against Pseudomonas aeruginosa. Moreover, Neroli oil exhibited a very strong antifungal activity determined by ABTS assay showed IC₅₀ values of 672 mg L-¹. Finally, this study may be considered as the first report on the biological properties of this essential oil. The results of this study have provided a starting point for the investigations to exploit new natural substances present in the essential oil of C. aurantium L. flowers

Effect of genotype and extraction method on polyphenols content, phenolic acids, and flavonoids of olive leaves (Olea europaea L. subsp. europaea)

Polyphenol’s extraction varied according to various factors. In this study, the effect of genotype and method of polyphenols extraction were investigated using leaves of two cultivated and two wild olive varieties and four hydromethanolic extraction methods. Quantitatively, significant differences were observed according to the extraction method, the genotype, and the interaction genotype-method of extraction. The heat reflux extraction showed the highest polyphenols content in wild olive leaves having an amount of 841.17 mg GAE/100 g DM. The qualitative phytochemical examination using high performance liquid chromatography (HPLC) of olive leaves showed some significant differences of phenolic compounds between genotypes. For the same oleaster genotype, the extraction method seemed to influence qualitatively the polyphenols profiles. The quinic acid was the dominant phenolic acid and the luteolin-7-O-glucoside was the major flavonoid observed in wild olive leaves having, respectively, 618.24 and 3211.44 mg/kg DM. The quinic acid has an amount of 400.15 and 275.39 mg/kg and the luteolin-7-O-glucoside has an amount of 2059.62 and 1214.49 mg/kg in cultivars leaves. The extraction by Soxhlet of wild olive leaves showed the highest quinic acid (1085.80 mg/kg DM) and luteolin-7-O-glucoside (3720.15 mg/kg DM) amounts. The hydromethanolic extraction assisted by Soxhlet of wild olive leaves constituted the optimal method to obtain high polyphenols contents enriched with phenolic acids and flavonoids

Effect of Short and Long Term Irrigation with Treated Wastewater on Chemical Composition and Herbicidal Activity of Eucalyptus camaldulensis Dehn. Essential Oils

[EN] Water shortage throughout the world, especially in arid regions in the later decades has led to search for alternatives to save potable fresh water. Treated wastewater (TWW) appears to be an opportunity for irrigation. However, it could represent a stress factor for plants, and influence their metabolism, changing their secondary metabolites and, consequently, their biological properties. Eucalyptus camaldulensis essential oil (EO) had been reported to possess phytotoxic activity. The main objective of this work was to compare the chemical composition and herbicidal activity of E. camaldulensis EO obtained from leaves of young plants and old trees irrigated with well water (WW) and TWW. Germination tests were performed in vitro against Amaranthus hybridus, Chenopodium album, Echinochloa crus-galli and Lolium perenne. The EOs composition was analyzed by gas chromatography and gas chromatography/mass spectrometry. A high percentage of oxygenated monoterpenes, with 1,8-cineole as main compound, was found in the EOs from leaves of young plants irrigated with both types of water. The EO from leaves of old trees irrigated with WW contained a main fraction of monoterpene hydrocarbons (45.17%) with p-cymene as principal compound. The highest herbicidal potential was shown by the EO from young plants irrigated with TWW. It completely inhibited A. hybridus and L. perenne germination, and nearly blocked the others at all concentrations assayed. It also showed strong phytotoxic activity on seedling length. The results suggest the possible use of TWW to irrigate Eucalyptus crops as it enhances the EOs herbicidal potential that could be used as natural herbicides.This work was supported by the Ministry of Higher Education and Scientific Research of Tunisia.Maaloul, A.; Verdeguer Sancho, MM.; Oddo, M.; Saadaoui, E.; Jebri, M.; Michalet, S.; Dijoux-Franca, M.... (2019). Effect of Short and Long Term Irrigation with Treated Wastewater on Chemical Composition and Herbicidal Activity of Eucalyptus camaldulensis Dehn. Essential Oils. Notulae Botanicae Horti Agrobotanici Cluj-Napoca. 47(4):1374-1381. https://doi.org/10.15835/nbha47411374S1374138147

Nine-Dimensional Bioprofiles of Tunisian Sages (Salvia officinalis, S. aegyptiaca and S. verbenaca) by High-Performance Thin-Layer Chromatography – Effect-Directed Analyses

Ethyl acetate extracts of Tunisian Salvia aegyptiaca and S. verbenaca aerial parts and S. officinalis leaves were examined via bioanalytical profiling using high-performance thin-layer chromatography (HPTLC) combined with nine bioactivity assays, namely antibacterial (Aliivibrio fischeri, Bacillus subtilis, and Rhodococcus fascians), antifungal (Bipolaris sorokiniana, and Fusarium avenaceum), radical scavenging (DPPH center dot), and enzyme inhibitory (alpha-glucosidase, acetylcholinesterase, and lipase) ones. The screening, us-ing toluene -ethyl acetate - methanol 6:3:0.5 (V/V/V) as a mobile phase, revealed five bioactive zones (a-e) that were analyzed by HPTLC-electrospray ionization-mass spectrometry (ESI-MS). Zones b and c, observed exclusively in S. officinalis, were active in all assays except alpha-glucosidase, and only c inhib-ited F. avenaceum. Compounds in these zones were identified by HPLC-high resolution tandem MS (LC-HRMS/MS) as rosmanol/epirosmanol and methyl carnosate, respectively. In the bioactive zones a and e, corosolic/maslinic acid and ursolic/oleanolic acid isomer pairs were present, which could be identified in all three Salvia species after their HPTLC separation using pre-chromatographic derivatization with iodine and MS detection. The triterpenes inhibited B. subtilis and R. fascians bacteria and alpha-glucosidase enzyme. Linoleic and linolenic acids were detected in zone d, which showed strong lipase inhibition in all three sage species

Eucalyptus oleosa Essential Oils: Chemical Composition and Antimicrobial and Antioxidant Activities of the Oils from Different Plant Parts (Stems, Leaves, Flowers and Fruits)

Essential oils obtained by hydrodistillation from the different parts (stems, adult leaves, immature flowers and fruits) of Eucalyptus oleosa were screened for their antioxidant and antimicrobial properties and their chemical composition. According to GC-FID and GC-MS, the principal compound of the stem, immature flowers and the fruit oils was 1,8-cineole, representing 31.5%, 47.0% and 29.1%, respectively. Spathulenol (16.1%) and γ-eudesmol (15.0%) were the two principal compounds of adult leaves oil. In the DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, the oils of the four parts showed moderate antioxidant activity. In the ABTS (2,2’-azinobis-3-ethylbenzothiazoline-6-sulphonate) assay, the most active part was the adult leaves, with a IC50 value 13.0 ± 0.6 mg/L, followed by stems (IC50 = 43.5 ± 1.4 mg/L). The essential oils showed a better antibacterial activity against Gram-positive and Gram-negative bacteria, and a significant antifungal activity also was observed against yeast-like fungi. A strong correlations between oxygenated monoterpenes and antimicrobial activity (especially 1,8-cineole) were noted (R2 = 0.99, 0.97 and 0.79 for B. subtilis, P. aeruginosa and C. albicans, respectively)