Antioxidant and antiproliferative activity of Laurus nobilis L. (Lauraceae) leaves and seeds essential oils against K562 human chronic myelogenous leukaemia cells

The antioxidant and antiproliferative activities of the essential oils from Laurus nobilis leaves and seeds in relation to their composition were analysed. The most abundant components of the leaf essential oil were 1,8-cineole, 1-p-menthen-8-ethyl acetate, linalool and sabinene, while the seed oil was characterised by β-ocimene, 1,8-cineole, α-pinene and β-pinene as main constituents. Both seed and leaf essential oils exhibited a scavenging effect on the DPPH radical, with IC?? values of 66.1 and 53.5?μg?mL?1, respectively. The leaf essential oil showed the strongest antioxidant activity in the β-carotene/linoleic acid system, with an IC?? value of 35.6?μg?mL?1 after 30?min of incubation. Both leaf and seed oils inhibited proliferation of the K562 tumour cell line with IC?? values of 95 and 75?μg?mL?1, respectively. The L. nobilis leaf oil showed a percentage of erythroide differentiation of 15% at a concentration of 10?μg?mL?1. A value of 12% was found for the seed essential oil at a concentration of 50?μg?mL?1. When the oils were added to a suboptimal concentration of the commercial drug, cytosine arabinoside, a clear synergic effect was observed.     

Chemical composition, antioxidant properties and anti-cholinesterase activity of Cordia gilletii (Boraginaceae) leaves essential oil

This study aimed to investigate for the first time the chemical composition, the antioxidant properties and the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the essential oil from the leaves of Cordia gilletii De Wild (Boraginaceae). The essential oil, characterized by 23 constituents (90.1% of the total oil), was constituted by terpene derivatives (25.6%) and non-terpene derivatives (64.5%), among which aldehydes, fatty acids and alkanes were present with the percentage of 16.5%, 18.8% and 23.1%, respectively. The antioxidant activity of C. gilletii essential oil was screened by two in vitro tests: DPPH and beta-carotene bleaching test. The essential oil revealed antioxidant activity with an IC50 value of 75.0 and 129.9 microg/mL on DPPH radical and beta-carotene decoloration tests, respectively. Moreover, C. gilletii inhibited AChE enzyme with an IC50 value of 105.6 microg/mL.     

HPLC analysis of supercritical carbon dioxide and compressed propane extracts from Piper amalago L. with antileishmanial activity

Piper amalago L. leaves were extracted with supercritical carbon dioxide and compressed propane under different conditions, and with chloroform by the conventional maceration method. These methods were compared for the pyrrolidine alkaloid content. Supercritical carbon dioxide (SFE-CO?) at 313 K and 12.55 MPa showed the highest selectivity for the main compound (600.53 mg/g of extract). A gradient high-performance liquid chromatography (HPLC) method was developed and validated to quantify the alkaloid N-[7-(3',4'-methylenedioxyphenyl)-2(Z),4(Z)-heptadienoyl]pyrrolidine in the extracts. The HPLC method showed linearity, precision and accuracy, allowing the quantitative analysis of the alkaloid in all the samples. All the extracts were tested against the promastigote and intracellular amastigote forms of Leishmania amazonensis. The antileishmanial activity was evaluated in terms of inhibitory concentration for 50% of protozoa (IC??). The cytotoxicity was also evaluated against J774A1 macrophages, and the cytotoxic concentrations for 50% of macrophages were obtained (CC??). The SFE-CO? (313 K; 12.55 MPa) extract showed the highest antileishmanial activity with the following IC?? values of 16 and 7 μg/mL against the promastigotes and intracellular amastigotes forms, respectively. The extract showed low cytotoxicity with a CC?? value of 93 μg/mL.     

Chemical and biological analyses of the essential oils and main constituents of Piper species

The essential oils obtained from leaves of Piper duckei and Piper demeraranum by hydrodistillation were analyzed by gas chromatography-mass spectrometry. The main constituents found in P. demeraranum oil were limonene (19.3%) and β-elemene (33.1%) and in P. duckei oil the major components found were germacrene D (14.7%) and trans-caryophyllene (27.1%). P. demeraranum and P. duckei oils exhibited biological activity, with IC(50) values between 15 to 76 μg mL(-1) against two Leishmania species, P. duckei oil being the most active. The cytotoxicity of the essential oils on mice peritoneal macrophage cells was insignificant, compared with the toxicity of pentamidine. The main mono- and sesquiterpene, limonene (IC(50) = 278 μM) and caryophyllene (IC(50) = 96 μM), were tested against the strains of Leishmania amazonensis, and the IC(50) values of these compounds were lower than those found for the essential oils of the Piper species. The HET-CAM test was used to evaluate the irritation potential of these oils as topical products, showing that these oils can be used as auxiliary medication in cases of cutaneous leishmaniasis, with less side effects and lower costs.     

Composition and antioxidant activity of essential oil of pimento (Pimenta dioica (L) Merr.) from Jamaica

The composition and antioxidant activity of the essential oil obtained through hydrodistillation of pimento berry [Pimenta dioica (L.) Merr] samples, namely P1 and P2, sourced from Jamaica, were studied. The chemical composition was analysed by GC and GC-MS methods. The antioxidant activities of the oils were evaluated in terms of their free-radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical cation and superoxide anion (?[image omitted]). Total phenolic content, total reducing power and metal-chelating capacity of the oils were also estimated. Forty-five constituents were identified. The major compound identified was eugenol (74.71%, 73.35%), followed by methyl eugenol (4.08%, 9.54%) and caryophyllene (4.90%, 3.30%). The antioxidant assays showed that the oils possess very high radical scavenging activities (DPPH IC(50) 4.82 ± 0.08, 5.14 ± 0.11 μg mL(-1), ABTS IC(50) 2.27 ± 0.16, 2.94 ± 0.03 μg mL(-1), superoxide IC(50) 17.78 ± 1.31, 20.65 ± 0.82 μg mL(-1)). The metal chelating capacities (IC(50) 83.62 ± 2.10, 101.77 ± 1.01 μg mL(-1)) and reducing power were also very high. The results show that the essential oils possess significant antioxidant activity which is comparable to that of pure eugenol. Therefore the oil can be utilised as a natural antioxidant which gives good flavour as well as health benefits.     

Cholinesterase inhibition activity of Marsilea quadrifolia Linn. an edible leafy vegetable from West Bengal, India

Maesilea quadrifolia Linn. (Marsileaceae) is a leafy vegetable well known in India. The current study aims to explore the phytochemical profile of M. quadrifolia and investigate its anti-cholinesterase potential. The methanol extract of the plant was subjected to qualitative and quantitative phytochemical screening (total alkaloidal content, saponin content and phenol content) and its anti-cholinesterase potential was tested by TLC bioautography and other screening methods using acytylcholinesterase (AChE) and butyrylcholinesterase (BChE). The study revealed that the extract contains various classes of phytoconstituents including steroids, saponins, alkaloids and other polyphenols. Total alkaloid, phenolic and saponin contents were found to be 19.3?mg?g?1 and 158.5?±?1.02?mg?g?1 as gallic acid equivalents and 2.63?mg?g?1 of the extract, respectively. The TLC bioautography method exhibited the inhibition of both enzymes. In a microtiter plate assay, the IC?? values of the extract for AChE and BChE were found to be 51.89?±?0.24?μg?mL?1 and 109.43?±?2.82?μg?mL?1, respectively. These findings suggest that M. quadrifolia is a potential lead as an AChE and BChE inhibitor, which may be useful in the management of Alzheimer's disease.     

Salvia officinalis L. from Italy: A Comparative Chemical and Biological Study of Its Essential Oil in the Mediterranean Context

Salvia officinalis L. (sage) is one of the most appreciated plants for its plethora of biologically active compounds. The objective of our research was a comparative study, in the Mediterranean context, of chemical composition, anticholinesterases, and antioxidant properties of essential oils (EOs) from sage collected in three areas (S1–S3) of Southern Italy. EOs were extracted by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory properties were investigated by employing Ellman’s method. Four in vitro assays, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), ferric-reducing ability power (FRAP), and β-carotene bleaching tests, were used to study the antioxidant effects. Camphor (16.16–18.92%), 1,8-cineole (8.80–9.86%), β-pinene (3.08–9.14%), camphene (6.27–8.08%), and α-thujone (1.17–9.26%) are identified as the most abundant constituents. However, the content of these constituents varied depending on environmental factors and pedoclimatic conditions. Principal component analysis (PCA) was performed. Based on Relative Antioxidant Capacity Index (RACI), S2 essential oil exhibited the highest radical potential with an IC₅₀ value of 20.64 μg/mL in ABTS test and presented the highest protection of lipid peroxidation with IC₅₀ values of 38.06 and 46.32 μg/mL after 30 and 60 min of incubation, respectively. The most promising inhibitory activity against BChE was found for S3 sample (IC₅₀ of 33.13 μg/mL).     

Antifungal activity, toxicity and chemical composition of the essential oil of Coriandrum sativum L. fruits

The aims of this study were to test the antifungal activity, toxicity and chemical composition of essential oil from C. sativum L. fruits. The essential oil, obtained by hydro-distillation, was analyzed by gas chromatography/mass spectroscopy. Linalool was the main constituent (58.22%). The oil was considered bioactive, showing an LC?? value of 23 μg/mL in the Artemia salina lethality test. The antifungal activity was evaluated against Microsporum canis and Candida spp. by the agar-well diffusion method and the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) were established by the broth microdilution method. The essential oil induced growth inhibition zones of 28 ± 5.42 and 9.25 ± 0.5 for M. canis and Candida spp. respectively. The MICs and MFCs for M. canis strains ranged from 78 to 620 and 150 to 1,250 μg/mL, and the MICs and MFCs for Candida spp strains ranged from 310 to 620 and 620 to 1,250 μg/mL, respectively. C. sativum essential oil is active in vitro against M. canis and Candida spp. demonstrating good antifungal activity.     

Chemical composition and antioxidant activities of ansu apricot oil growing wild in north Xinjiang, China

Ansu apricots growing wild in north Xinjiang are recognised as being one of the major wild-plant resources in China. In order to improve the level of comprehensive utilisation and the number of cultivated apricot varieties, the chemical composition of ansu apricot oil was analysed by capillary GC-MS and elucidated based on the standard mass spectral data; the antioxidant activities were also evaluated. Seven components of ansu apricots oil were identified, and the total unsaturated fatty acid (FA) (TUFA) and total essential FA (TEFA) contents of the ansu apricot oil were found to be 90.35 g/100 g and 48.93 g/100 g, respectively. The scavenging capacity of the ansu apricots oil in the superoxide anion radical system and the hydroxyl radical system performed better than in the DPPH radical system. The IC?? values of the ansu apricot oil for the superoxide anion radical system and the hydroxyl radical system were 0.15 mg mL?1 and 0.30 mg mL?1, respectively: stronger than that of the control (ascorbic acid). In the DPPH system, the IC?? value of the ansu apricot oil was 0.50 mg mL?1, and the IC?? value of ascorbic acid was 0.30 mg mL?1, but within the selected dosage, the highest scavenging capacity of ansu apricot oil was higher than the control. The results obtained in this study clearly suggest that ansu apricot oil is a natural source of antioxidants and could serve as a functional food ingredient with potential application in food products and thus provide related health benefits.     

Characterisation of the essential oil of Nepeta glomerata Montbret et Aucher ex Bentham from Lebanon and its biological activities

The essential oil of Nepeta glomerata from Lebanon was studied by means of GC and GC/MS analysis; 70 compounds were identified. The oil was constituted mainly by monoterpenes and the most abundant components were α-pinene, spathulenol and carvacrol. Nepeta glomerata oil showed antibacterial activity, particularly towards Gram-positive bacteria, and also inhibited LPS-induced NO production in macrophage cell line RAW 264.7, with an IC(50) value of 78.1 μg mL(-1). Furthermore, an in?vitro cytotoxic assay showed that the oil was more active on a renal adenocarcinoma cell line (48% of inhibition of proliferation at 100 μg mL(-1)) in comparison to an amelanotic melanoma.     

Chemical composition, and antioxidant and antimicrobial activities of essential Oil of Phyllostachys heterocycla cv. Pubescens varieties from China

The essential oils of Phyllostachys heterocycla cv. Pubescens, Phyllostachys heterocycla cv. Gracilis, Phyllostachys heterocycla cv. Heterocycla and Phyllostachys kwangsiensis leaves were obtained by steam distillation. Their chemical components were separated and identified by gas chromatography/mass spectrometry (GC/MS). Meanwhile, the effect of scavenging free radicals of essential oil was assayed by using the DPPH·method with Trolox? as control to evaluate their antioxidant capacities. Gram-positive (Staphyloccocus aureus) and Gram-negative (Escherichia coli) were selected as the indicator microorganisms to evaluate the antimicrobial activity. Antimicrobial properties were estimated by the agar diffusion method. The results show that 63 components were separated and identified by GC/MS from these varieties of bamboo leaves. cis-3-Hexenol, whose content in cv. Pubescens, Gracilis, Heterocycla and Ph. kwangsiensis was 27.11%, 24.62%, 30.51% and 34.65%, respectively, was the main constituent. The relative content of alcohol compounds in these varieties of essential oils ranged from 39.8% to 46.64%. All of the bamboo leaf essential oils possessed certain antioxidant capacity; the corresponding IC?? values were 3.1622, 4.9353, 4.2473, and 5.4746 μL/mL, respectively. Essential oils of all tested bamboo spp. were active against Staphylococcus epidermidis and E. coli, showing a positive correlation with the essential oil concentration of 50.42-300 μL/mL. The results indicated there were no significant differences among three varieties and the related species with respect to their antioxidant and antimicrobial activities. This paper provides evidence for studying the essential composition from different varieties of bamboo leaves.     

Components and insecticidal activity against the maize weevils of Zanthoxylum schinifolium fruits and leaves

In our screening program for new agrochemicals from Chinese medicinal herbs and wild plants, Zanthoxylum schinifolium essential oils were found to possess strong insecticidal activity against the maize weevil Sitophilus zeamais. The essential oils of Z. schinifolium fruits and leaves were extracted via hydrodistillation and investigated by GC and GC-MS. Estragole (69.52%) was the major compound of the essential oil of fresh fruits, followed by linalool (8.63%) and limonene (4.34%) and 94.33% of the total components were monoterpenoids. The main components of the essential oil of fresh leaves were linalool (12.94%), ar-tumerone (8.95%), limonene (6.45%) and elixene (5.43%) and only 50.62% were monoterpenoids. However, the essential oil from purchased fruits contained linalool (33.42%), limonene (13.66%) and sabinene (5.72%), followed by estragole (4.67%), nerol (4.56%) and 4-terpineol (4.27%). Estragole, linalool and sabinene were separated and purified by silica gel column chromatography and preparative thin layer chromatography, and further identified by means of physicochemical and spectrometric analysis. The essential oil from the fresh fruits (LD?? = 15.93 μg/adult) possessed two times more toxicity to the insects compared with that of fresh leaves (LD?? = 35.31 μg/adult). Estragole, linalool and sabinene exhibited contact activity against S. zeamais with LD?? values of 17.63, 13.90 and 23.98 μg/adult, respectively. The essential oils of Z. schinifolium possessed strong fumigant toxicity against S. zeamais adults with LC?? values of 13.19 mg/L (fresh fruits), 24.04 mg/L (fresh leaves) and 17.63 mg/L (purchased fruits). Estragole, linalool and sabinene also exhibited strong fumigant toxicity against the maize weevils with LC?? values of 14.10, 10.46 and 9.12 mg/L, respectively.     

Enhancement of Cholinesterase Inhibition of Alpinia galanga (L.) Willd. Essential Oil by Microemulsions

This study aimed to investigate the chemical composition and reveal the selective inhibitory activity of Alpinia galanga (L.) Willd. essential oil (AGO) on acetylcholinesterase (AChE) compared to butyrylcholinesterase (BChE). The chemical composition of AGO was investigated by means of gas chromatography–mass spectrometry. Ellman’s method was used to determine the inhibitory activities against AChE and BChE. Microemulsion systems with desirable anticholinesterase effects were developed. Methyl cinnamate and 1,8-cineole were reported as the major component of AGO. The IC₅₀ values of A. galanga oil against AChE and BChE were 24.6 ± 9.6 and 825.4 ± 340.1 µg/mL, respectively. The superior selectivity of AGO on AChE (34.8 ± 8.9) compared to galantamine hydrobromide (6.4 ± 1.5) suggested AGO to be an effective ingredient with fewer side effects for Alzheimer’s treatment. Interestingly, the microemulsion of AGO possessed significantly higher anticholinesterase activity than that of native oil alone. Therefore, microemulsion of AGO is a promising alternative approach for the treatment of Alzheimer’s disease.     

Chemical composition, antimicrobial and antitumor activities of the essential oils and crude extracts of Euphorbia macrorrhiza

The present study aimed to examine the chemical composition and biological activity of essential oils extracted from Euphorbia macrorrhiza collected from Northwest China. The major constituents of the essential oils of aerial parts and roots of E. macrorrhiza are acorenone B (16.72% and 25.80%), (+)-cycloisosativene (14.94% and 12.40%), 3a-hydroxy-5b-androstane (10.62% and 5.52%), copaene (7.37% and 6.29%), l-calamenene (4.13% and 4.65%) and β-cedrene (8.40% and 7.98%), respectively. The minor components of them are thymene, γ-terpinene, thymecamphor, α-cedrene, zingiberene, trans-caryophyllene, β-chamigrene, curcumene, pentadecane, (-)-α-muurolene, cuparene, γ-cadinene, (Z)-3-heptadecene, 1,3,7,7-tetramethyl-2-oxabicyclo(4.4.0)dec-5-en-4-one, hexahydrofarnesyl acetone, γ-elixene and palmitinic acid. The antimicrobial and antitumor activitiy of the E. macrorrhiza essential oil against Staphyloccocus aureus, Escherichia coli, Canidia Albicans and Caco-2 cells were evaluated. Among all the tested microorganisms and Caco-2 cells, the essential oils showed the strongest inhibitory effect on Staphyloccocus aureus (MIC = 2.8 μg/mL) and Caco-2 cell (IC?? = 11.86 μg/mL), whereas no effect on Escherichia coli and Candida albicans. The data of this study suggested that the E. macrorrhiza essential oils have great potential as a natural medicine for microbial infections and cancers.     

Comparative analysis of the oil and supercritical CO(2) extract of Schinus molle L. growing in Yemen

In this study, we report the preliminary data on the chemical composition of Yemeni Schinus molle L. volatile oil obtained by supercritical extraction with carbon dioxide (40°C and 90?bar), SFE, and by hydrodistillation (HD). The composition of the volatile oil has been analysed by GC and GC-MS. The content of the major constituents in the oils from leaves varied in the following ranges: germacrene D 3.7% in SFE and 16.7% in HD; β-caryophyllene 19.1% in SFE and 13.5% in HD. The amount of monoterpenes constituted 4%, in all the analysed samples, while the number of sesquiterpenes was 44% in supercritical and 67% in HD oil. Some compounds were not identified by GC-MS and it will require further analysis using other analytical techniques.     

Extraction of essential oil from Pimpinella anisum using supercritical carbon dioxide and comparison with hydrodistillation

Supercritical fluid extraction (SFE) of essential oil from Pimpinella anisum, using carbon dioxide as a solvent is presented in this work. An orthogonal array design OA9 (3(4)) was applied to select the optimum extraction condition. The effects of pressure, temperature, dynamic extraction time and methanol volume on the extraction efficiency were investigated by the three-level orthogonal array design. Results show that pressure has a significant effect on the extraction efficiency. The extract obtained from P. anisum by using supercritical fluid extraction was compared with the essential oil obtained by hydrodistillation, considering both quantity and quality of the product. SFE products were found to be of markedly different composition, compared with the corresponding hydrodistilated oil. The total amount of extractable substances obtained in SFE (7.5%) is higher than that obtained by hydrodistillation (3.1%) and SFE is faster than hydrodistillation method.     

Chemical composition and antimicrobial activity of the essential oils of Onychopetalum amazonicum R.E.Fr.

The essential oils from leaves, twigs and trunk bark of Onychopetalum amazonicum R.E. Fr. (Annonaceae), obtained by hydrodistillation, were analysed by GC and GC–MS, and also were evaluated for in vitro antimicrobial activity. Forty-one compounds, which correspond to 75.0–92.2% of the oil components, were identified. Major compounds were sesquiterpenes, including (E)-caryophyllene, caryophyllene oxide, spathulenol, α-gurjunene, allo-aromadendrene and α-epi-cadinol. The oils were evaluated for antimicrobial activities against four bacteria strains and five pathogenic fungi. The oil of the trunk bark exhibited good activity against Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 10538 and Kocuria rhizophila ATCC 9341, with a minimal inhibitory concentration of 62.5 μg/mL. The essential oil composition and the antimicrobial evaluation are reported for the first time for the genus Onychopetalum.     

Insecticidal activity of essential oil of Carum Carvi fruits from China and its main components against two grain storage insects

During our screening program for agrochemicals from Chinese medicinal herbs and wild plants, the essential oil of Carum carvi fruits was found to possess strong contact toxicity against Sitophilus zeamais and Tribolium castaneum adults, with LD?? values of 3.07 and 3.29 μg/adult, respectively, and also showed strong fumigant toxicity against the two grain storage insects with LC?? values of 3.37 and 2.53 mg/L, respectively. The essential oil obtained by hydrodistillation was investigated by GC and GC-MS. The main components of the essential oil were identified to be (R)-carvone (37.98%) and D-limonene (26.55%) followed by α-pinene (5.21), cis-carveol (5.01%) and β-myrcene (4.67%). (R)-Carvone and D-limonene were separated and purified by silica gel column chromatography and preparative thin layer chromatography, and further identified by means of physicochemical and spectrometric analysis. (R)-Carvone and D-limonene showed strong contact toxicity against S. zeamais (LD?? = 2.79 and 29.86 μg/adult) and T. castaneum (LD?? = 2.64 and 20.14 μg/adult). (R)-Carvone and D-limonene also possessed strong fumigant toxicity against S. zeamais (LC?? = 2.76 and 48.18 mg/L) and T. castaneum adults (LC?? = 1.96 and 19.10 mg/L).     

Chemical composition,antioxidant and antimicrobial activity of the essential oil from the leaves of Macleaya cordata (Willd) R. Br.

The essential oil from the leaves of Macleaya cordata R.Br. obtained by hydrodistillation was analysed by gas chromatography/mass spectrometry. Sixty-eight compounds consisting of up to 92.53% of the essential oil were identified. Antioxidant activities of the essential oil were evaluated by using DPPH radical scavenging and β-carotene–linoleic acid assays. The essential oil showed moderate antioxidant activity. In addition, the essential oil exhibited potential antimicrobial activity against all tested microorganisms, with diameters of inhibition zones ranging from 8.7 ± 0.5 to 17.2 ± 1.2 mm and minimum inhibitory concentration values from 125 to 500 μg/mL. We selected the most sensitive bacterium Staphylococcus aureus as model to observe of the action of essential oils of M. cordata on the membrane structure by scanning electron microscopy. The treated cell membranes were damaged severely. The results presented here indicate that the essential oil of M. cordata may be potential sources of antioxidant and antimicrobial agents in the future.